index.json

[{"authors":["brady"],"categories":null,"content":"","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"600b37a6c685c9f950e11aa431d3e004","permalink":"/authors/hueber/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/hueber/","section":"authors","summary":"","tags":null,"title":"Brady Hueber","type":"authors"},{"authors":["rhianna"],"categories":null,"content":"Rhianna is currently involved in many projects involving ImageStream Flow Cytometry, ELISPOTs and other flow techniques. She hopes to go to graduate school for a masters in genetic counseling in the future.\n","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"901b8dbecf1129f7481953a63f6d7077","permalink":"/authors/jones/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/jones/","section":"authors","summary":"Rhianna is currently involved in many projects involving ImageStream Flow Cytometry, ELISPOTs and other flow techniques. She hopes to go to graduate school for a masters in genetic counseling in the future.","tags":null,"title":"Rhianna Jones","type":"authors"},{"authors":["kyle"],"categories":null,"content":"Soon-to be masters student of bioinformatics at the University of Maryland University College. Research interests include: transcriptomic profiling of memory-like NK cells, transcriptomic modulation during viral infection, and automated analyses of flow cytometry data.\nOutside of the lab I enjoy competitive strength sports, hiking, and cycling around the Fells.\n","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"07d7f7a4632e9242f3afcd64183300e4","permalink":"/authors/kroll/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/kroll/","section":"authors","summary":"Soon-to be masters student of bioinformatics at the University of Maryland University College. Research interests include: transcriptomic profiling of memory-like NK cells, transcriptomic modulation during viral infection, and automated analyses of flow cytometry data.\nOutside of the lab I enjoy competitive strength sports, hiking, and cycling around the Fells.","tags":null,"title":"Kyle Kroll","type":"authors"},{"authors":["cordelia"],"categories":null,"content":"","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"51f2caae86c21426d25dca1b296610ca","permalink":"/authors/manickam/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/manickam/","section":"authors","summary":"","tags":null,"title":"Cordelia Manickam","type":"authors"},{"authors":["daniel"],"categories":null,"content":"","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"28cbdcf7dd6f4683acaf23c147126704","permalink":"/authors/ram/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/ram/","section":"authors","summary":"","tags":null,"title":"Daniel Ram","type":"authors"},{"authors":["reeves"],"categories":null,"content":"Dr. R. Keith Reeves is currently Associate Professor of Medicine at Harvard Medical School and the Center for Virology and Vaccine Research (CVVR) of BIDMC. He is the Director of the Harvard CFAR Advanced Technologies Core, Director of the CVVR Flow Cytometry Core and an Associate Member of the Ragon Institute of MGH, MIT, and Harvard. He also works within the HIV Vaccine Trials Network (HVTN) and the BEAT-HIV Martin Delaney Cure Collaboratory. Dr. Reeves obtained his PhD in the laboratory of Dr. Patricia Fultz at the University of Alabama-Birmingham in 2007 where his work focused on plasmacytoid dendritic cells as a mediator of inflammation in lentivirus infections. Dr. Reeves then completed his postdoctoral work and was junior faculty at the New England Primate Research Center of Harvard Medical School where his studies focused on natural killer (NK) cell biology in nonhuman primates. He has published extensively in this field providing some of the most comprehensive analyses of NK cells and innate lymphoid cells (ILC) in HIV, SIV, and HCV infections to date, including the first characterization of memory NK cells in any primate species. Dr. Reeves’ research, largely supported by individual and consortia grants from NIAID, NIDCR, and amfAR, currently focuses on harnessing NK cells in the context of vaccines and antiviral therapeutics for HIV, CMV and HCV.\n","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"7bbb8034747c432c15c8d91ac4cb7712","permalink":"/authors/reeves/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/reeves/","section":"authors","summary":"Dr. R. Keith Reeves is currently Associate Professor of Medicine at Harvard Medical School and the Center for Virology and Vaccine Research (CVVR) of BIDMC. He is the Director of the Harvard CFAR Advanced Technologies Core, Director of the CVVR Flow Cytometry Core and an Associate Member of the Ragon Institute of MGH, MIT, and Harvard. He also works within the HIV Vaccine Trials Network (HVTN) and the BEAT-HIV Martin Delaney Cure Collaboratory.","tags":null,"title":"Keith Reeves","type":"authors"},{"authors":["spandan"],"categories":null,"content":"","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"ac9d36c2b5ed46388bfcf78b5a377d1b","permalink":"/authors/shah/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/shah/","section":"authors","summary":"","tags":null,"title":"Spandan Shah","type":"authors"},{"authors":["smith"],"categories":null,"content":"","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"c7c12ef0302ac4dd5f46c82785bf7550","permalink":"/authors/smith/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/smith/","section":"authors","summary":"","tags":null,"title":"S. Smith","type":"authors"},{"authors":["val"],"categories":null,"content":"","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"19d4324d53ea724aad6663604f8c3b3b","permalink":"/authors/varner/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/varner/","section":"authors","summary":"","tags":null,"title":"Valerie Varner","type":"authors"},{"authors":["griffin"],"categories":null,"content":"","date":1616284800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1616284800,"objectID":"fac012c25130f934461bde0803e4470b","permalink":"/authors/woolley/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/woolley/","section":"authors","summary":"","tags":null,"title":"Griffin Woolley","type":"authors"},{"authors":["sho"],"categories":null,"content":"","date":1596240000,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1596240000,"objectID":"ed65ff64d123fdd16517ac2a1020d757","permalink":"/authors/sugawara/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/sugawara/","section":"authors","summary":"","tags":null,"title":"Sho Sugawara","type":"authors"},{"authors":["michelle"],"categories":null,"content":"","date":1575158400,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1575158400,"objectID":"b0789205775ddcbfd6eb6c6f5a63b3f2","permalink":"/authors/lifton/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/lifton/","section":"authors","summary":"","tags":null,"title":"Michelle Lifton","type":"authors"},{"authors":["joshua"],"categories":null,"content":"","date":1569888000,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1569888000,"objectID":"3449dcb1cdb584dee543477a2af66432","permalink":"/authors/ghofrani/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/ghofrani/","section":"authors","summary":"","tags":null,"title":"Joshua Ghofrani","type":"authors"},{"authors":["jost"],"categories":null,"content":"My lab is currently addressing whether human NK cells are endowed with antigenic specificity and immunological memory to viruses, and how interactions between NK cells and other immune cells modulate the development of virus-specific adaptive immune responses. The primary goal of those studies is to provide the rationale to develop novel approaches aiming at harnessing NK cell function to enhance the efficacy of future vaccines.\n","date":1569888000,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1569888000,"objectID":"2988c22543f9cf5c47d43438783f2ec4","permalink":"/authors/jost/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/jost/","section":"authors","summary":"My lab is currently addressing whether human NK cells are endowed with antigenic specificity and immunological memory to viruses, and how interactions between NK cells and other immune cells modulate the development of virus-specific adaptive immune responses. The primary goal of those studies is to provide the rationale to develop novel approaches aiming at harnessing NK cell function to enhance the efficacy of future vaccines.","tags":null,"title":"Stephanie Jost","type":"authors"},{"authors":["olivier"],"categories":null,"content":"Exploring the relationship between NK cells and HIV infection in order to understand the development of NK cells antigen-specific responses.\n","date":1564617600,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1564617600,"objectID":"c706d5dfd016dddab35f42a2d1452116","permalink":"/authors/lucar/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/lucar/","section":"authors","summary":"Exploring the relationship between NK cells and HIV infection in order to understand the development of NK cells antigen-specific responses.","tags":null,"title":"Olivier Lucar","type":"authors"},{"authors":["philippe"],"categories":null,"content":"","date":1506816000,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":1506816000,"objectID":"18cd39d508fb8179a9c0722945a8405e","permalink":"/authors/rascle/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/rascle/","section":"authors","summary":"","tags":null,"title":"Philippe Rascle","type":"authors"},{"authors":["alexander"],"categories":null,"content":"","date":-62135596800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":-62135596800,"objectID":"d1fac08957a284fa63a4ffe3436f810a","permalink":"/authors/cope/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/cope/","section":"authors","summary":"","tags":null,"title":"Alexander Cope","type":"authors"},{"authors":["stephaniee"],"categories":null,"content":"","date":-62135596800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":-62135596800,"objectID":"0865998d71c2a3c3eb4f740d330b5e3a","permalink":"/authors/etienne/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/etienne/","section":"authors","summary":"","tags":null,"title":"Stephanie Etienne","type":"authors"},{"authors":["rachel"],"categories":null,"content":"","date":-62135596800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":-62135596800,"objectID":"dccb0999f6af5f7e4d2ba910e58e1ccf","permalink":"/authors/hindin/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/hindin/","section":"authors","summary":"","tags":null,"title":"Rachel Hindin","type":"authors"},{"authors":["matthew"],"categories":null,"content":"","date":-62135596800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":-62135596800,"objectID":"c9d1f07746fb67ef088e68cac4a25834","permalink":"/authors/mosher/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/mosher/","section":"authors","summary":"","tags":null,"title":"Matthew Mosher","type":"authors"},{"authors":["somai"],"categories":null,"content":"","date":-62135596800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":-62135596800,"objectID":"f63b89327d4d0175121e5830b8387c21","permalink":"/authors/nwokike/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/nwokike/","section":"authors","summary":"","tags":null,"title":"Somuayiro Nwokike","type":"authors"},{"authors":["mercay"],"categories":null,"content":"","date":-62135596800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":-62135596800,"objectID":"b334c4508d939587407eee4c669f5d4f","permalink":"/authors/reuter/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/reuter/","section":"authors","summary":"","tags":null,"title":"Mercay Reuter","type":"authors"},{"authors":["allie"],"categories":null,"content":"","date":-62135596800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":-62135596800,"objectID":"eaa7006cda8772cf4f5d537d7074d955","permalink":"/authors/werner/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/werner/","section":"authors","summary":"","tags":null,"title":"Allie Werner","type":"authors"},{"authors":["taylor"],"categories":null,"content":"","date":-62135596800,"expirydate":-62135596800,"kind":"taxonomy","lang":"en","lastmod":-62135596800,"objectID":"7498364f8a952b0a6d15568217d9b4b5","permalink":"/authors/yoder/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/authors/yoder/","section":"authors","summary":"","tags":null,"title":"Taylor Yoder","type":"authors"},{"authors":null,"categories":null,"content":"Please check back in later or follow us on  for new opportunities in the Reeves Group.\n","date":1536451200,"expirydate":-62135596800,"kind":"section","lang":"en","lastmod":1536451200,"objectID":"c5284dcbd42aede8aba5bc96e7a337c3","permalink":"/jobs/reeves/","publishdate":"2018-09-09T00:00:00Z","relpermalink":"/jobs/reeves/","section":"jobs","summary":"Please check back in later or follow us on  for new opportunities in the Reeves Group.","tags":null,"title":"Open Positions","type":"docs"},{"authors":null,"categories":null,"content":"            ","date":-62135596800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":-62135596800,"objectID":"ae3b9ba272818ade4ee0bdee8b6bf1f0","permalink":"/gal/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/gal/","section":"","summary":"            ","tags":null,"title":"Gallery","type":"page"},{"authors":["Rhianna Jones","Cordelia Manickam","Daniel Ram","Kyle Kroll","Brady Hueber","Griffin Woolley","Spandan Shah","S. Smith","Valerie Varner","Keith Reeves"],"categories":null,"content":"","date":1616284800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1616284800,"objectID":"6ba5d749340afa25f2323a012ca3a834","permalink":"/publication/granulocyterxiv/","publishdate":"2020-08-01T00:00:00Z","relpermalink":"/publication/granulocyterxiv/","section":"publication","summary":"","tags":null,"title":"Systemic and mucosal mobilization of granulocyte subsets during lentivirus infection\n","type":"publication"},{"authors":["Cordelia Manickam","Sho Sugawara","Keith Reeves"],"categories":null,"content":"","date":1596240000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1596240000,"objectID":"1ff9a91bb1ee8a110b08925576ffe9ad","permalink":"/publication/32845937/","publishdate":"2020-08-01T00:00:00Z","relpermalink":"/publication/32845937/","section":"publication","summary":"The COVID-19 pandemic has caused more than 575,000 deaths worldwide as of mid-July 2020 and still continues globally unabated. Immune dysfunction and cytokine storm complicate the disease, which in turn leads to the question of whether stimulation or suppression of the immune system would curb the disease. Given the varied antiviral and regulatory functions of natural killer (NK) cells, they could be potent and powerful immune allies in this global fight against COVID-19. Unfortunately, there is somewhat limited knowledge of the role of NK cells in SARS-CoV-2 infections and even in the related SARS-CoV-1 and MERS-CoV infections. Several NK cell therapeutic options already exist in the treatment of tumor and other viral diseases and could be repurposed against COVID-19. In this review, we describe the current understanding and potential roles of NK cells and other Fc receptor (FcR) effector cells in SARS-CoV-2 infection, advantages of using animals to model COVID-19, and NK cell-based therapeutics that are being investigated for COVID-19 therapy.\n","tags":null,"title":"Friends or foes? The knowns and unknowns of natural killer cell biology in COVID-19 and other coronaviruses in July 2020.\n","type":"publication"},{"authors":["Daniel Ram","Kyle Kroll","Keith Reeves"],"categories":null,"content":"","date":1596240000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1596240000,"objectID":"94c1e276d53028e1912f2bb2a3bdb0f6","permalink":"/publication/32862656/","publishdate":"2020-08-01T00:00:00Z","relpermalink":"/publication/32862656/","section":"publication","summary":"Natural killer (NK) cells provide some of the earliest immune responses to infection, but when viruses manipulate or perturb the immune environment to alter NK cell function this places the host at a disadvantage. Indeed, others and we observe that in the context of HIV/SIV infection, although NK cells are not infected they can become dysfunctional over time. Several works have characterized protein and transcriptional profiles of NK cells during HIV/SIV infection, but none have examined whether the production of alternative transcripts and corresponding isoforms is modulated. This phenomenon occurs broadly in normal biology and in other disease states, and could provide a novel avenue of investigation that may yield better targets to restore or augment NK cell responses to HIV/SIV. Herein, we briefly summarize published and new data that may provide a perspective on how to target NK cell splice variants.\n","tags":null,"title":"Skipped over - tuning NK cells towards HIV through alternative splicing.\n","type":"publication"},{"authors":["Daniel Ram","Arias","Kyle Kroll","Brady Hueber","Cordelia Manickam","Rhianna Jones","S. Smith","Spandan Shah","Valerie Varner","Keith Reeves"],"categories":null,"content":"","date":1593561600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1593561600,"objectID":"0bf52b2b44f435d17501325159ce845e","permalink":"/publication/32849583/","publishdate":"2020-07-01T00:00:00Z","relpermalink":"/publication/32849583/","section":"publication","summary":"CD49a+ tissue resident NK cells have been implicated in memory-like NK cell responses, but while this population is well-characterized in mice and in humans, they are poorly described in non-human primates (NHP) which are particularly critical for modeling human viral infections. Others and we have shown that memory-like NK cells are enriched in the liver and because of the importance of NHP in modeling HIV infection, understanding the immunobiology of CD49a+ NK cells in SIV-infected rhesus macaques is critical to explore the role of this cell type in retroviral infections. In this study mononuclear cells isolated from livers, spleens, and peripheral whole blood were analyzed in acutely and chronically lentivirus-infected and experimentally-nave Indian rhesus macaques (RM). NK cells were then identified as CD45+CD14-CD20-CD3-NKG2A/C+ cells and characterized using multiparametric flow-cytometry. Our data show that in RM, CD49a+ NK cells increase in the liver following retroviral infections [median = 5.2% (nave) vs. median = 9.48% (SIV+) or median = 16.8% (SHIV+)]. In contrast, there is little change in CD49a+ NK frequencies in whole blood or spleens of matched animals. In agreement with human and murine data we also observed that CD49a+ NK cells were predominantly Eomeslow T-betlow, though these frequencies are elevated in infected animal cohorts. Functionally, our data suggests that infection alters TNF-, IFN-, and CD107a expression in stimulated CD49a+ NK cells. Specifically, our analyses found a decrease in CD49a+ CD107a+ TNF+ IFN- NK cells, with a simultaneous increase in CD49a+ CD107a+ TNF- IFN+ NK cells and the non-responsive CD49a+ CD107a- TNF- IFN- NK cell population following infection, suggesting both pathogenic and inflammatory changes in the NK cell functional profile. Our data also identified significant global differences in polyfunctionality between CD49a+ NK cells in the nave and chronic (SHIV+) cohorts. Our work provides the first characterization of CD49a+ NK cells in tissues from RM. The significant similarities between CD49a+ NK cells from RM and what is reported from human samples justifies the importance of studying CD49a+ NK cells in this species to support preclinical animal model research.\n","tags":null,"title":"Characterization of Rhesus Macaque Liver-Resident CD49a+ NK Cells During Retrovirus Infections.\n","type":"publication"},{"authors":["Mercado","Zahn","Wegmann","Loos","Chandrashekar","Yu","Liu","Peter","McMahan","Tostanoski","He","Martinez","Rutten","Bos","van","Vellinga","Custers","Langedijk","Kwaks","Bakkers","Zuijdgeest","Huber","Atyeo","Fischinger","Burke","Feldman","Hauser","Caradonna","Bondzie","Dagotto","Gebre","Hoffman","Jacob-Dolan","Kirilova","Li","Lin","Mahrokhian","Maxfield","Nampanya","Nityanandam","Nkolola","Patel","Ventura","Verrington","Wan","Pessaint","Ry","Blade","Strasbaugh","Cabus","Brown","Cook","Zouantchangadou","Teow","Andersen","Lewis","Cai","Chen","Schmidt","Keith Reeves","Baric","Lauffenburger","Alter","Stoffels","Mammen","Hoof","Schuitemaker","Barouch"],"categories":null,"content":"","date":1593561600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1593561600,"objectID":"e1eea85049da09b01e311966c7aa6651","permalink":"/publication/32731257/","publishdate":"2020-07-01T00:00:00Z","relpermalink":"/publication/32731257/","section":"publication","summary":"A safe and effective vaccine for severe acute respiratory syndrome coronavirus2 (SARS-CoV-2) may be required to end the coronavirus disease2019 (COVID-19) pandemic1-8. For global deployment and pandemic control, a vaccine that requires only a single immunization would be optimal. Here we show the immunogenicity and protective efficacy of a single dose of adenovirus serotype26 (Ad26) vector-based vaccines expressing the SARS-CoV-2 spike (S) protein in nonhuman primates. Fifty-two rhesus macaques were immunized with Ad26 vectors encoding S variants or sham control and were challenged with SARS-CoV-2 by the intranasal and intratracheal routes9,10. The optimal Ad26 vaccine induced robust neutralizing antibody responses and provided complete or near-complete protection in bronchoalveolar lavage and nasal swabs following SARS-CoV-2 challenge. Vaccine-elicited neutralizing antibody titres correlated with protective efficacy, suggesting an immune correlate of protection. These data demonstrate robust single-shot vaccine protection against SARS-CoV-2 in nonhuman primates. The optimal Ad26 vector-based vaccine for SARS-CoV-2, termed Ad26.COV2.S, is currently being evaluated in clinical trials.\n","tags":null,"title":"Single-shot Ad26 vaccine protects against SARS-CoV-2 in rhesus macaques.\n","type":"publication"},{"authors":["Aid","Daniel Ram","Bosinger","Barouch","Keith Reeves"],"categories":null,"content":"","date":1585699200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1585699200,"objectID":"af068a51dad991534fa1f5924ae0bbef","permalink":"/publication/32411625/","publishdate":"2020-04-01T00:00:00Z","relpermalink":"/publication/32411625/","section":"publication","summary":"Natural killer (NK) cells are crucial regulators of antiviral and anti-tumor immune responses. Although in humans some NK cell transcriptional programs are relatively well-established, NK cell transcriptional networks in non-human primates (NHP) remain poorly delineated. Here we performed RNA-Seq experiments using purified NK cells from experimentally nave rhesus macaques, providing the first transcriptional characterization of pure NK cells in any NHP species. This novel NK cell transcriptomic signature (NK RMtsig) overlaps with published human NK signatures, allowing us to identify new key signaling and transcription factor networks underlying NK cell function. Finally, we show that applying NK RMtsig to an unrelated rhesus macaque cohort infected with SIVmac251 or ZIKV can sensitively detect NK cell repertoire perturbations, thus confirming applicability of this approach. In sum, we propose this NHP NK cell signature will serve as a useful resource for future studies involving infection, disease or treatment modalities in NHP.\n","tags":null,"title":"Delineation and Modulation of the Natural Killer Cell Transcriptome in Rhesus Macaques During ZIKV and SIV Infections.\n","type":"publication"},{"authors":["Brady Hueber","Curtis","Kyle Kroll","Valerie Varner","Rhianna Jones","Pathak","Michelle Lifton","Van","De","Keith Reeves"],"categories":null,"content":"","date":1575158400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1575158400,"objectID":"5d674723271da927eccd42db4adbd4bf","permalink":"/publication/31801861/","publishdate":"2019-12-01T00:00:00Z","relpermalink":"/publication/31801861/","section":"publication","summary":"Mother-to-child transmission of HIV-1 via breastfeeding is responsible for nearly half of children newly infected with HIV. Although innate lymphoid cells (ILC) and natural killer (NK) cells are found throughout the oral mucosae, the effects of HIV/SHIV in these tissues are largely unknown. To better understand the mechanics of postnatal transmission we performed a comprehensive study of SIV/SHIV-infected infant rhesus macaques (RM) and tracked changes in frequency, trafficking, and function of ILC3 and NK cells using polychromatic flow cytometry and cell stimulation assays in colon, tonsil and oral lymph node samples. Infection led to a 3-fold depletion of ILC3 in the colon and an increase in NK cells in tonsils and oral lymph nodes. ILC3 and NK cells saw alterations in their trafficking repertoires as a result of infection, with increased expression of CD103 in colon NK cells and curtailment of CXCR3, and a significant decrease in 47 expression in colon ILC3. SPICE analyses revealed that ILC3 and NK cells displayed distinct functional profiles by tissue in nave samples. Infection perturbed these profiles, with a near total loss of IL-22 production in the tonsil and colon and increase in CD107a, IFN- and TNF- from ILC3, and increase in CD107a, MIP-1 and TNF- from NK cells. Collectively, these data reveal that lentiviurus infection alters the frequency, receptor repertoires, and functions of innate cells in the oral and gut mucosa of infants. Further study will be required to delineate the full extent that these changes have on oral and gut homeostasis, SHIV/SIV pathogenesis and oral opportunistic disease.Importance Vertical transmission of HIV from mother-to-child accounts for many of the new cases seen worldwide. To date, there is no vaccine to mitigate this transmission and limited research on the effects that lentiviral infection has on the innate immune system in oral tissues of infected children. To fill this knowledge gap, our lab studied infant rhesus macaques to evaluate how acute SIV/SHIV infections impacted ILC3 and NK cells; immune cells critical for mucosal homeostasis and antimicrobial defense. Our data revealed that SIV/SHIV infection led to a depletion of ILC3 and increase of NK cells, and a functional shift from homoestatic to multifunctional proinflammatory. Taken together, we describe how lentiviral infection perturbs the oral and gastrointestinal mucosae of infant macaques through alterations of resident innate immune cells giving rise to chronic inflammation and potentially exacerbating morbidity and mortality in children living with HIV.\n","tags":null,"title":"Functional perturbation of mucosal group 3 innate lymphoid and natural killer cells in SHIV/SIV-infected infant rhesus macaques.\n","type":"publication"},{"authors":["Tan","Joshua Ghofrani","Geiger","Koralnik","Stephanie Jost"],"categories":null,"content":"","date":1569888000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1569888000,"objectID":"ff9c17044f7b768320e1dc9f144befc5","permalink":"/publication/31513076/","publishdate":"2019-10-01T00:00:00Z","relpermalink":"/publication/31513076/","section":"publication","summary":"BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is an often fatal disease caused by JC virus (JCV) in severely immunocompromised patients, including HIV patients. Development of therapeutics to prevent or treat PML is an urgent medical need. While JCV-specific T cells are crucial to control JCV and recover from PML, the role played by antibodies remains unclear. Anti-JCV antibodies, including potent neutralizing antibodies, can be detected in most infected adults, yet in PML patients, JCV seems to escape from neutralization. Whether antibodies can contribute to JCV control by eliciting Fc-mediated effector functions activity has not been evaluated.\n      METHODS: We measured the capacity of plasma anti-JCV VP1 antibodies to recruit Fc receptor (FcR)-bearing effector cell functions in 28 HIV patients, comparing subjects without PML with PML survivors (PML S) who were alive 1 year after disease onset or PML progressors (PML P) who succumbed within the first year. Antibody titers against JCV VP1 and HIV gp140 trimer were determined by end-point titer dilution ELISA. FcR-mediated natural killer cell degranulation and IFN- production were measured as surrogate for in vitro antibody-dependent cellular cytotoxicity (ADCC).\n      RESULTS: PML S had higher JCV antibody titers than PML P and patients without PML. However, anti-JCV antibodies had a higher ability to functionally engage FcR in PML P than PML S. Antibody titers and ADCC activity did not vary over time in PML S. Anti-HIV antibody titers and ADCC activity were similar among groups.\n      CONCLUSIONS: The ability of anti-JCV antibodies to stimulate FcR-bearing effector cell activity might contribute to the outcome of PML. Further studies are warranted to define Fc-mediated functions of anti-JCV antibodies and evaluate whether ADCC can contain JCV replication.\n","tags":null,"title":"Brief Report: Decreased JC Virus-Specific Antibody-Dependent Cellular Cytotoxicity in HIV-Seropositive PML Survivors.\n","type":"publication"},{"authors":["Truitt","Yang","Espinoza","Fan","Daniel Ram","Mostrm","Tran","Sprehe","Keith Reeves","Donahue","Kaur","Dunbar","Wu"],"categories":null,"content":"","date":1569888000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1569888000,"objectID":"9a70c6b3c30968ec6f4b6871e622dc91","permalink":"/publication/31649681/","publishdate":"2019-10-01T00:00:00Z","relpermalink":"/publication/31649681/","section":"publication","summary":"Recent functional, gene expression, and epigenetic studies have suggested the presence of a subset of mature natural killer (NK) cells responsible for maintaining NK cell memory. The lack of endogenous clonal markers in NK cells impedes understanding the genesis of these cell populations. In humans, primates, and mice, this phenotype and memory or adaptive functions have been strongly linked to cytomegalovirus or related herpes virus infections. We have used transplantation of lentivirally-barcoded autologous hematopoietic stem and progenitor cells (HSPC) to track clonal hematopoiesis in rhesus macaques and previously reported striking oligoclonal expansions of NK-biased barcoded clones within the CD56-CD16+ NK cell subpopulation, clonally distinct from ongoing output of myeloid, B cell, T cell, and CD56+16- NK cells from HSPC. These CD56-CD16+ NK cell clones segregate by expression of specific KIR surface receptors, suggesting clonal expansion in reaction to specific environmental stimuli. We have now used this model to investigate the impact of rhesus CMV(RhCMV) infection on NK clonal dynamics. Following transplantation, RhCMVneg rhesus macaques display less dominant and oligoclonal CD16+ NK cells biased clones compared to RhCMVpos animals, however these populations of cells are still clearly present. Upon RhCMV infection, CD16+ NK cells proliferate, followed by appearance of new groups of expanded NK clones and disappearance of clones present prior to RhCMV infection. A second superinfection with RhCMV resulted in rapid viral clearance without major change in the mature NK cell clonal landscape. Our findings suggest that RhCMV is not the sole driver of clonal expansion and peripheral maintenance of mature NK cells; however, infection of macaques with this herpesvirus does result in selective expansion and persistence of specific NK cell clones, providing further information relevant to adaptive NK cells and the development of NK cell therapies.\n","tags":null,"title":"Impact of CMV Infection on Natural Killer Cell Clonal Repertoire in CMV-Nave Rhesus Macaques.\n","type":"publication"},{"authors":["Olivier Lucar","Keith Reeves","Stephanie Jost"],"categories":null,"content":"","date":1564617600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1564617600,"objectID":"16cbb903c829bdc92783d05cb008ad05","permalink":"/publication/31474977/","publishdate":"2019-08-01T00:00:00Z","relpermalink":"/publication/31474977/","section":"publication","summary":"Despite efficient suppression of plasma viremia in people living with HIV (PLWH) on cART, evidence of HIV-induced immunosuppression remains, and normally benign and opportunistic pathogens become major sources of co-morbidities, including virus-induced cancers. In fact, cancer remains a primary cause of death even in virally suppressed PLWH. Natural killer (NK) cells provide rapid early responses to HIV infection, contribute substantially to disease modulation and vaccine protection, and are also major therapeutic targets for cancer immunotherapy. However, much like other lymphocyte populations, recent burgeoning evidence suggests that in chronic conditions like HIV, NK cells can become functionally exhausted with impaired cytotoxic function, altered cytokine production and impaired antibody-dependent cell-mediated cytotoxicity. Recent work suggests functional anergy is likely due to low-level ongoing virus replication, increased inflammatory cytokines, or increased presence of MHClow target cells. Indeed, HIV-induced loss of NK cell-mediated control of lytic EBV infection has been specifically shown to cause lymphoma and also increases replication of CMV. In this review, we will discuss current understanding of NK cell modulation of HIV disease, reciprocal exhaustion of NK cells, and how this may impact increased cancer incidences and prospects for NK cell-targeted immunotherapies. Finally, we will review the most recent evidence supporting adaptive functions of NK cells and highlight the potential of adaptive NK cells for cancer immunotherapy.\n","tags":null,"title":"A Natural Impact: NK Cells at the Intersection of Cancer and HIV Disease.\n","type":"publication"},{"authors":["Montano","Bhasin","D'Aquila","Erlandson","Evans","Funderburg","Justice","Ndhlovu","Ojikutu","Pahor","Pahwa","Ryan","Schrack","Schultz","Sebastiani","Sinclair","Tripp","Walker","Womack","Yung","Keith Reeves"],"categories":null,"content":"","date":1564617600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1564617600,"objectID":"1fd4328bb8176c60a08b086f9b0fa883","permalink":"/publication/31456412/","publishdate":"2019-08-01T00:00:00Z","relpermalink":"/publication/31456412/","section":"publication","summary":"People aging with HIV infection (PAWH) experience greater impairments in physical and cognitive function, in addition to higher rates of peripheral comorbid conditions (e.g. renal failure, diabetes, bone fracture, hypertension, cardiovascular disease, polypharmacy and multimorbidity). While multifactorial drivers including HIV infection itself, antiretroviral therapy (ART)-related toxicities, disparities in care and biobehavioral factors likely contribute, there remains an overarching question as what are the relevant age-related mechanisms and models that could inform interventions that promote healthspan and lifespan in PAWH? This workshop was convened to hear from experts on the biology of aging and HIV researchers studying PAWH to focus on advancing investigation at the interface of HIV and Aging. Here we summarize the discussions from the Harvard Center for AIDS Research and Boston Claude D. Pepper co-sponsored workshop on HIV and Aging, which took place in October of 2018.\n","tags":null,"title":"HARVARD HIV AND AGING WORKSHOP: PERSPECTIVES AND PRIORITIES FROM CLAUDE D. PEPPER CENTERS AND CENTERS FOR AIDS RESEARCH.\n","type":"publication"},{"authors":["DeWolfe","Aid","McGann","Joshua Ghofrani","Geiger","Helzer","Malik","Kleiboeker","Stephanie Jost","Tan"],"categories":null,"content":"","date":1564617600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1564617600,"objectID":"87ec2c1e7f0f21b9a1cffb639acd4b9d","permalink":"/publication/31507586/","publishdate":"2019-08-01T00:00:00Z","relpermalink":"/publication/31507586/","section":"publication","summary":"Background: A previously proposed immune risk profile (IRP), based on T cell phenotype and CMV serotype, is associated with mortality in the elderly and increased infections post-kidney transplant. To evaluate if NK cells contribute to the IRP and if the IRP can be predicted by a clinical T cell functional assays, we conducted a cross sectional study in renal transplant candidates to determine the incidence of IRP and its association with specific NK cell characteristics and ImmuKnow value. Material and Methods: Sixty five subjects were enrolled in 5 cohorts designated by age and dialysis status. We determined T and NK cell phenotypes by flow cytometry and analyzed multiple factors contributing to IRP. Results: We identified 14 IRP+ [CMV seropositivity and CD4/CD8 ratio ","tags":null,"title":"NK Cells Contribute to the Immune Risk Profile in Kidney Transplant Candidates.\n","type":"publication"},{"authors":["Cordelia Manickam","Keith Reeves"],"categories":null,"content":"","date":1564617600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1564617600,"objectID":"7d97b27a3958b71feb812b10b3768c33","permalink":"/publication/31444146/","publishdate":"2019-08-01T00:00:00Z","relpermalink":"/publication/31444146/","section":"publication","summary":"PMID: 31444146 [PubMed - as supplied by publisher]\n","tags":null,"title":"Silent damage? Occult HCV replication and histological disease may occur following apparent HCV clearance.\n","type":"publication"},{"authors":null,"categories":null,"content":"","date":1561420800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1561420800,"objectID":"6db9975410713fbc8dcdfbe07ae30012","permalink":"/project/cytodrav/","publishdate":"2019-06-25T00:00:00Z","relpermalink":"/project/cytodrav/","section":"project","summary":"Dimensionality Reduction and Visualization for Flow Cytometry","tags":["Programming"],"title":"CytoDRAV","type":"project"},{"authors":["Kyle Kroll"],"categories":null,"content":"Utilizing RNA-seq technologies, I am trying to understand the underlying mechanisms of NK cell memory responses towards HIV and CMV.\n","date":1561420800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1561420800,"objectID":"b5b4b985f5f848bfaef606c31285c5be","permalink":"/project/transcriptomic-clones/","publishdate":"2019-06-25T00:00:00Z","relpermalink":"/project/transcriptomic-clones/","section":"project","summary":"Attempting to find a transcriptomic signature of single-cell NK clones that respond in a memory-like fasion to HIV antigens.","tags":["Transcriptomics","RNAseq"],"title":"Transcriptomic Signatures of HIV-specific NK Clones","type":"project"},{"authors":["kyle"],"categories":["Misc"],"content":"Hello and welcome to the new home for the Reeves and Jost Labs!\nThe goal of this new website is to offer a better understanding of the work we do and how it fits into the broader view of understanding the underlying mechanisms of HIV/SIV and CMV infections.\n","date":1561334400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1561399961,"objectID":"127e1842dded7d392338bcf93f28d38c","permalink":"/post/welcome/","publishdate":"2019-06-24T00:00:00Z","relpermalink":"/post/welcome/","section":"post","summary":"Hello and welcome to the new home for the Reeves and Jost Labs!\nThe goal of this new website is to offer a better understanding of the work we do and how it fits into the broader view of understanding the underlying mechanisms of HIV/SIV and CMV infections.","tags":["Blog"],"title":"Welcome","type":"post"},{"authors":["Daniel Ram","Olivier Lucar","Brady Hueber","Keith Reeves"],"categories":null,"content":"","date":1559347200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1559347200,"objectID":"6b736d412bebfe0ade9d6a7176e21b45","permalink":"/publication/31167916/","publishdate":"2019-06-01T00:00:00Z","relpermalink":"/publication/31167916/","section":"publication","summary":"Recently others and we have shown that NK cells exhibit memory-like recall responses against CMV and HIV/SIV infections. Although the mechanism(s) have not been fully delineated, several groups have shown that the activating receptor NKG2C is elevated on NK cells in the context of rhesus CMV (rhCMV) or human CMV (hCMV) infections. CD94, which heterodimerizes with NKG2C is also linked to adaptive NK cell responses. Because non-human primates (NHP) play a crucial role in modeling HIV (SIV) infections, it is crucial to be able to assess and characterize the NKG2 family in NHP. Unfortunately it is not possible to detect CD94 using commercially available antibodies in NHP. Our work, a first for NHP, has focused on developing RNA-flow cytometry using mRNA transcripts as proxies distinguishing NKG2C from NKG2A. We have expanded the application of this technology and here we show the first characterization of CD94 (KLRD1)+ NK cells in NHP using multiparametric RNA-Flow cytometry. Peripheral blood mononuclear cells (PBMCs) from nave and matched acutely (n=4) or chronically (n=12) SIV-infected rhesus macaques were analyzed by flow cytometry using commercially available antibodies, determining expression of transcripts for NKG2A, NKG2C and CD94 (KLRC1, KLRC2 and KLRD1 respectively) on NK cells using RNA-flow cytometry. Our data show that KLRC1KLRC2+KLRD1+ NK cells decrease following chronic, but not acute, infection with SIV. This approach will allow us to investigate the kinetics of infection and NK memory formation, and will further improve our understanding of basic NK cell biology, especially in the context of SIV infection.Importance:Non-human primates play a crucial role in approximating human biology and many diseases that are difficult, if not impossible, to achieve in other animal models, notably HIV. Current advances in adaptive NK cell research positions us to address fundamental deficiencies in our fight against infection and disease at the earliest moments following infection, or substantially earlier in disease progression. Here we show that we can identify specific NK cell subpopulations that are modulated following chronic, but not acute, SIV infection. The ability to identify these subsets more precisely will inform therapeutic and vaccine strategies targeting an optimized NK cell response.\n","tags":null,"title":"SIV infection modulates CD94 (KLRD1)+ NK cells in rhesus macaques.\n","type":"publication"},{"authors":["Lewis","Ackerman","Scarlatti","Moog","Robert-Guroff","Kent","Overbaugh","Keith Reeves","Ferrari","Thyagarajan"],"categories":null,"content":"","date":1556668800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1556668800,"objectID":"d93f59761b6c618dbcfeeaa3e47a30ba","permalink":"/publication/31134085/","publishdate":"2019-05-01T00:00:00Z","relpermalink":"/publication/31134085/","section":"publication","summary":"It is now well-accepted that Fc-mediated effector functions, including antibody-dependent cellular cytotoxicity (ADCC), can contribute to vaccine-elicited protection as well as post-infection control of HIV viremia. This picture was derived using a wide array of ADCC assays, no two of which are strictly comparable, and none of which is qualified at the clinical laboratory level. An earlier comparative study of assay protocols showed that while data from different ADCC assay formats were often correlated, they remained distinct in terms of target cells and the epitopes and antigen(s) available for recognition by antibodies, the effector cells, and the readout of cytotoxicity. This initial study warrants expanded analyses of the relationships among all current assay formats to determine where they detect overlapping activities and where they do not. Here we summarize knowns and unknowns of assaying ADCC against HIV-1.\n","tags":null,"title":"Knowns and Unknowns of Assaying Antibody-Dependent Cell-Mediated Cytotoxicity Against HIV-1.\n","type":"publication"},{"authors":["Cordelia Manickam","Spandan Shah","Nohara","Ferrari","Keith Reeves"],"categories":null,"content":"","date":1556668800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1556668800,"objectID":"8511dcdf851918de65c587c4bc75f839","permalink":"/publication/31191520/","publishdate":"2019-05-01T00:00:00Z","relpermalink":"/publication/31191520/","section":"publication","summary":"Natural killer (NK) cells are the major innate effectors primed to eliminate virus-infected and tumor or neoplastic cells. Recent studies also suggest nuances in phenotypic and functional characteristics among NK cell subsets may further permit execution of regulatory and adaptive roles. Animal models, particularly non-human primate (NHP) models, are critical for characterizing NK cell biology in disease and under homeostatic conditions. In HIV infection, NK cells mediate multiple antiviral functions via upregulation of activating receptors, inflammatory cytokine secretion, and antibody dependent cell cytotoxicity through antibody Fc-FcR interaction and others. However, HIV infection can also reciprocally modulate NK cells directly or indirectly, leading to impaired/ineffective NK cell responses. In this review, we will describe multiple aspects of NK cell biology in HIV/SIV infections and their association with viral control and disease progression, and how NHP models were critical in detailing each finding. Further, we will discuss the effect of NK cell depletion in SIV-infected NHP and the characteristics of newly described memory NK cells in NHP models and different mouse strains. Overall, we propose that the role of NK cells in controlling viral infections remains incompletely understood and that NHP models are indispensable in order to efficiently address these deficits.\n","tags":null,"title":"Monkeying Around: Using Non-human Primate Models to Study NK Cell Biology in HIV Infections.\n","type":"publication"},{"authors":["Joshua Ghofrani","Olivier Lucar","Dugan","Keith Reeves","Stephanie Jost"],"categories":null,"content":"","date":1554076800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1554076800,"objectID":"ce4f5b079beaad72afd7da79793200c6","permalink":"/publication/31016720/","publishdate":"2019-04-01T00:00:00Z","relpermalink":"/publication/31016720/","section":"publication","summary":"Cytokine-induced memory-like (CIML) NK cells are endowed with the capacity to mediate enhanced effector functions upon cytokine or activating receptor restimulation for several weeks following short-term preactivation with IL-12, IL-15, and IL-18. Promising results from a first-in-human clinical trial highlighted the clinical potential of CIML NK cells as adoptive immunotherapy for patients with hematologic malignancies. However, the mechanisms underlying CIML NK cell differentiation and increased functionality remain incompletely understood. Semaphorin 7A (SEMA7A) is a potent immunomodulator expressed in activated lymphocytes and myeloid cells. In this study, we show that SEMA7A is substantially upregulated on NK cells stimulated with cytokines, and specifically marks activated NK cells with a strong potential to release IFN-. In particular, preactivation of NK cells with IL-12+IL-15+IL-18 resulted in greater than tenfold upregulation of SEMA7A and enhanced expression of the ligand for SEMA7A, integrin-1, on CIML NK cells. Strikingly, preactivation in the presence of antibodies targeting SEMA7A lead to significantly decreased IFN- production following restimulation. These results imply a novel mechanism by which cytokine-enhanced SEMA7A/integrin-1 interaction promotes CIML NK cell differentiation and maintenance of increased functionality. Our data suggest that targeting SEMA7A/integrin-1 signaling might provide a novel immunotherapeutic approach to potentiate antitumor activity of CIML NK cells.\n","tags":null,"title":"Semaphorin 7A modulates cytokine-induced memory-like responses by human natural killer cells.\n","type":"publication"},{"authors":["Cordelia Manickam","Li","Spandan Shah","Kyle Kroll","Keith Reeves"],"categories":null,"content":"","date":1551398400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1551398400,"objectID":"2ca76e5d0d13ab9d0600ad76baf88055","permalink":"/publication/30418531/","publishdate":"2019-03-01T00:00:00Z","relpermalink":"/publication/30418531/","section":"publication","summary":"Natural killer (NK) cells are primary immune effector cells with both innate and potentially adaptive functions against viral infections, but commonly become exhausted or dysfunctional during chronic diseases such as human immunodeficiency virus (HIV). Chimpanzees are the closest genetic relatives of humans and have been previously used in immunology, behavior and disease models. Due to their similarities to humans, a better understanding of chimpanzee immunology, particularly innate immune cells, can lend insight into the evolution of human immunology, as well as response to disease. However, the phenotype of NK cells has been poorly defined. In order to define NK cell phenotypes, we unbiasedly quantified NK cell markers among mononuclear cells in both naive and HIV-infected chimpanzees by flow cytometry. We identified NKG2D and NKp46 as the most dominant stable NK cells markers using multidimensional data reduction analyses. Other traditional NK cell markers such as CD8, CD16 and perforin fluctuated during infection, while some such as CD56, NKG2A and NKp30 were generally unaltered by HIV infection, but did not delineate the full NK cell repertoire. Taken together, these data indicate that phenotypic dysregulation may not be pronounced during HIV infection of chimpanzees, but traditional NK cell phenotyping used for both humans and other non-human primate species may need to be revised to accurately identify chimpanzee NK cells.\n","tags":null,"title":"Non-linear multidimensional flow cytometry analyses delineate NK cell phenotypes in normal and HIV-infected chimpanzees.\n","type":"publication"},{"authors":["Daniel Ram","Cordelia Manickam","Olivier Lucar","Spandan Shah","Keith Reeves"],"categories":null,"content":"","date":1548979200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1548979200,"objectID":"d88e4439f19637d43527c5bf859192de","permalink":"/publication/30730588/","publishdate":"2019-02-01T00:00:00Z","relpermalink":"/publication/30730588/","section":"publication","summary":"NK cells play a critical role in antiviral and antitumor responses. Although current NK cell immune therapies have focused primarily on cancer biology, many of these advances can be readily applied to target HIV/simian immunodeficiency virus (SIV)-infected cells. Promising developments include recent reports that CAR NK cells are capable of targeted responses while producing less off-target and toxic side effects than are associated with CAR T cell therapies. Further, CAR NK cells derived from inducible pluripotent stem cells or cell lines may allow for more rapid \"off-the-shelf\" access. Other work investigating the IL-15 superagonist ALT-803 (now N803) may also provide a recourse for enhancing NK cell responses in the context of the immunosuppressive and inflammatory environment of chronic HIV/SIV infections, leading to enhanced control of viremia. With a broader acceptance of research supporting adaptive functions in NK cells it is likely that novel immunotherapeutics and vaccine modalities will aim to generate virus-specific memory NK cells. In doing so, better targeted NK cell responses against virus-infected cells may usher in a new era of NK cell-tuned immune therapy.\n","tags":null,"title":"Adaptive NK cell responses in HIV/SIV infections: A roadmap to cell-based therapeutics?\n","type":"publication"},{"authors":["Spandan Shah","Cordelia Manickam","Daniel Ram","Kyle Kroll","Itell","Permar","Barouch","Klatt","Keith Reeves"],"categories":null,"content":"","date":1543622400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1543622400,"objectID":"20966c9fe42b5d354f72658d3a262ad1","permalink":"/publication/30517864/","publishdate":"2018-12-01T00:00:00Z","relpermalink":"/publication/30517864/","section":"publication","summary":"Despite burgeoning evidence demonstrating the adaptive properties of natural killer (NK) cells, mechanistic data explaining these phenomena are lacking. Following antibody sensitization, NK cells lacking the Fc receptor (FcR) signaling chain (g) acquire adaptive features, including robust proliferation, multifunctionality, rapid killing, and mobilization to sites of virus exposure. Using the rhesus macaque model, we demonstrate the systemic distribution of g NK cells expressing memory features, including downregulated Helios and Eomes. Furthermore, we find that g NK cells abandon typical -chain/Syk in lieu of CD3-Zap70 signaling. FCRIIIa (CD16) density, mucosal homing, and function are all coupled to this alternate signaling, which in itself requires priming by rhesus cytomegalovirus (rhCMV). Simian immunodeficiency virus (SIV) infections further expand gut-homing adaptive NK cells but result in pathogenic suppression of CD3-Zap70 signaling and function. Herein, we provide a mechanism of virus-dependent alternative signaling that may explain the acquisition of adaptive features by primate NK cells and could be targeted for future vaccine or curative therapies.\n","tags":null,"title":"CMV Primes Functional Alternative Signaling in Adaptive g NK Cells but Is Subverted by Lentivirus Infection in Rhesus Macaques.\n","type":"publication"},{"authors":["Cordelia Manickam","Spandan Shah","Olivier Lucar","Daniel Ram","Keith Reeves"],"categories":null,"content":"","date":1543622400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1543622400,"objectID":"90c8f5627393ece596fd027725b17da5","permalink":"/publication/30568659/","publishdate":"2018-12-01T00:00:00Z","relpermalink":"/publication/30568659/","section":"publication","summary":"Viral infections trigger robust secretion of interferons and other antiviral cytokines by infected and bystander cells, which in turn can tune the immune response and may lead to viral clearance or immune suppression. However, aberrant or unrestricted cytokine responses can damage host tissues, leading to organ dysfunction, and even death. To understand the cytokine milieu and immune responses in infected host tissues, non-human primate (NHP) models have emerged as important tools. NHP have been used for decades to study human infections and have played significant roles in the development of vaccines, drug therapies and other immune treatment modalities, aided by an ability to control disease parameters, and unrestricted tissue access. In addition to the genetic and physiological similarities with humans, NHP have conserved immunologic properties with over 90% amino acid similarity for most cytokines. For example, human-like symptomology and acute respiratory syndrome is found in cynomolgus macaques infected with highly pathogenic avian influenza virus, antibody enhanced dengue disease is common in neotropical primates, and in NHP models of viral hepatitis cytokine-induced inflammation induces severe liver damage, fibrosis, and hepatocellular carcinoma recapitulates human disease. To regulate inflammation, anti-cytokine therapy studies in NHP are underway and will provide important insights for future human interventions. This review will provide a comprehensive outline of the cytokine-mediated exacerbation of disease and tissue damage in NHP models of viral infections and therapeutic strategies that can aid in prevention/treatment of the disease syndromes.\n","tags":null,"title":"Cytokine-Mediated Tissue Injury in Non-human Primate Models of Viral Infections.\n","type":"publication"},{"authors":["Mudd","Busman-Sahay","DiNapoli","Lai","Sheik","Lisco","Deleage","Richardson","Palesch","Paiardini","Cameron","Sereti","Keith Reeves","Estes","Brenchley"],"categories":null,"content":"","date":1535760000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1535760000,"objectID":"28b5bfd4900014bb413df27c666ee2ed","permalink":"/publication/30262807/","publishdate":"2018-09-01T00:00:00Z","relpermalink":"/publication/30262807/","section":"publication","summary":"Innate lymphoid cells (ILCs) play critical roles in mucosal barrier defense and tissue homeostasis. While ILCs are depleted in HIV-1 infection, this phenomenon is not a generalized feature of all viral infections. Here we show in untreated SIV-infected rhesus macaques (RMs) that ILC3s are lost rapidly in mesenteric lymph nodes (MLNs), yet preserved in SIV+ RMs with pharmacologic or natural control of viremia. In healthy uninfected RMs, experimental depletion of CD4+ T cells in combination with dextran sodium sulfate (DSS) is sufficient to reduce ILC frequencies in the MLN. In this setting and in chronic SIV+ RMs, IL-7R chain expression diminishes on ILC3s in contrast to the IL-18R chain expression which remains stable. In HIV-uninfected patients with durable CD4+ T cell deficiency (deemed idiopathic CD4+ lymphopenia), similar ILC deficiencies in blood were observed, collectively identifying determinants of ILC homeostasis in primates and potential mechanisms underlying their depletion in HIV/SIV infection.\n","tags":null,"title":"Hallmarks of primate lentiviral immunodeficiency infection recapitulate loss of innate lymphoid cells.\n","type":"publication"},{"authors":["Daniel Ram","Kyle Kroll","Keith Reeves"],"categories":null,"content":"","date":1535760000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1535760000,"objectID":"798e95b0a68cf6ab57ba430d3b1431a4","permalink":"/publication/30256418/","publishdate":"2018-09-01T00:00:00Z","relpermalink":"/publication/30256418/","section":"publication","summary":"The oral mucosae and draining lymph nodes are primary entry points for invading pathogens, particularly during immunosuppressive HIV/SIV infections. Innate immunity against oral stimuli, including natural killer (NK) cells, is understudied. Herein, we demonstrate functional NK cell responses to pathogen-associated molecular patterns (PAMPs) of potential oral pathogens in rhesus macaques.\n","tags":null,"title":"Indirect activation of rhesus macaque (Macaca mulatta) NK cells in oral and mucosal draining lymph nodes.\n","type":"publication"},{"authors":["Cordelia Manickam","Nwanze","Daniel Ram","Spandan Shah","S. Smith","Rhianna Jones","Brady Hueber","Kyle Kroll","Valerie Varner","Goepfert","Stephanie Jost","Keith Reeves"],"categories":null,"content":"","date":1530403200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1530403200,"objectID":"c139e022a094477bd8e99854cf2fdd39","permalink":"/publication/29734222/","publishdate":"2018-07-01T00:00:00Z","relpermalink":"/publication/29734222/","section":"publication","summary":"OBJECTIVE: Recently, a seemingly novel innate immune cell subset bearing features of natural killer and B cells was identified in mice. So-called NKB cells appear as first responders to infections, but whether this cell population is truly novel or is in fact a subpopulation of B cells and exists in higher primates remains unclear. The objective of this study was to identify NKB cells in primates and study the impact of HIV/SIV infections.\n      DESIGN AND METHODS: NKB cells were quantified in both naive and lentivirus infected rhesus macaques and humans by excluding lineage markers (CD3, CD127) and positive Boolean gating for CD20, NKG2A/C and/or NKp46. Additional phenotypic measures were conducted by RNA-probe and traditional flow cytometry.\n      RESULTS: Circulating cytotoxic NKB cells were found at similar frequencies in humans and rhesus macaques (range, 0.01-0.2% of total lymphocytes). NKB cells were notably enriched in spleen (median, 0.4% of lymphocytes), but were otherwise systemically distributed in tonsil, lymph nodes, colon, and jejunum. Expression of immunoglobulin was highly variable, but heavily favoured IgM and IgA rather than IgG. Interestingly, NKB cell frequencies expanded in PBMC and colon during SIV infection, as did IgG expression, but were generally unaltered in HIV-infected humans.\n      CONCLUSION: These results suggest a cell type expressing both natural killer and B-cell features exists in rhesus macaques and humans and are perturbed by HIV/SIV infection. The full functional niche remains unknown, but the unique phenotype and systemic distribution could make NKB cells unique targets for immunotherapeutics or vaccine strategies.\n","tags":null,"title":"Progressive lentivirus infection induces natural killer cell receptor-expressing B cells in the gastrointestinal tract.\n","type":"publication"},{"authors":["Hensley-McBain","Berard","Manuzak","Miller","Zevin","Polacino","Gile","Agricola","Cameron","Hu","Estes","Keith Reeves","Smedley","Keele","Burgener","Klatt"],"categories":null,"content":"","date":1527811200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1527811200,"objectID":"791d02c8df2dd8946d862d6f1bf59c04","permalink":"/publication/29907866/","publishdate":"2018-06-01T00:00:00Z","relpermalink":"/publication/29907866/","section":"publication","summary":"HIV and pathogenic SIV infection are characterized by mucosal dysfunction including epithelial barrier damage, loss of Th17 cells, neutrophil infiltration, and microbial translocation with accompanying inflammation. However, it is unclear how and when these contributing factors occur relative to one another. In order to determine whether any of these features initiates the cycle of damage, we longitudinally evaluated the kinetics of mucosal and systemic T-cell activation, microbial translocation, and Th17 cell and neutrophil frequencies following intrarectal SIV infection of rhesus macaques. We additionally assessed the colon proteome to elucidate molecular pathways altered early after infection. We demonstrate increased T-cell activation (HLA-DR+) beginning 3-14 days post-SIV challenge, reduced peripheral zonulin 3-14 days post-SIV, and evidence of microbial translocation 14 days post-SIV. The onset of mucosal dysfunction preceded peripheral and mucosal Th17 depletion, which occurred 14-28 days post-SIV, and gut neutrophil accumulation was not observed. Proteins involved in epithelial structure were downregulated 3 days post-SIV followed by an upregulation of immune proteins 14 days post-SIV. These data demonstrate that immune perturbations such as Th17 loss and neutrophil infiltration occur after alterations to epithelial structural protein pathways, suggesting that epithelial damage occurs prior to widespread immune dysfunction.\n","tags":null,"title":"Intestinal damage precedes mucosal immune dysfunction in SIV infection.\n","type":"publication"},{"authors":["Hogan","Krner","Hobbs","Simoneau","Thanh","Gibson","Palmer","Pandit","Marty","Kuritzkes","Stephanie Jost","Ritz","Henrich"],"categories":null,"content":"","date":1527811200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1527811200,"objectID":"b084ffa269f82d94bc6559e0e49a6099","permalink":"/publication/29921650/","publishdate":"2018-06-01T00:00:00Z","relpermalink":"/publication/29921650/","section":"publication","summary":"PMID: 29921650 [PubMed - indexed for MEDLINE]\n","tags":null,"title":"NK-cell activation is associated with increased HIV transcriptional activity following allogeneic hematopoietic cell transplantation.\n","type":"publication"},{"authors":["Blass","Aid","Martinot","Larocca","Kang","Badamchi-Zadeh","Penaloza-MacMaster","Keith Reeves","Barouch"],"categories":null,"content":"","date":1525132800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1525132800,"objectID":"681a09edc9aca65b6face623b6cde419","permalink":"/publication/29514912/","publishdate":"2018-05-01T00:00:00Z","relpermalink":"/publication/29514912/","section":"publication","summary":"Natural killer (NK) cells respond rapidly as a first line of defense against infectious pathogens. In addition, NK cells may provide a \"rheostat\" function and have been shown to reduce the magnitude of antigen-specific T cell responses following infection to avoid immunopathology. However, it remains unknown whether NK cells similarly modulate vaccine-elicited T cell responses following virus challenge. We used the lymphocytic choriomeningitis virus (LCMV) clone 13 infection model to address whether NK cells regulate T cell responses in adenovirus vector-vaccinated mice following challenge. As expected, NK cell depletion in unvaccinated mice resulted in increased virus-specific CD4+ and CD8+ T cell responses and immunopathology following LCMV challenge. In contrast, NK cell depletion had minimal to no impact on antigen-specific T cell responses in mice that were vaccinated with an adenovirus serotype 5 (Ad5)-GP vector prior to LCMV challenge. Moreover, NK cell depletion in vaccinated mice prior to challenge did not result in immunopathology and did not compromise protective efficacy. These data suggest that adenovirus vaccine-elicited T cells may be less sensitive to NK cell rheostat regulation than T cells primed by LCMV infection.IMPORTANCE Recent data have shown that NK cell depletion leads to enhanced virus-elicited T cell responses that can result in severe immunopathology following LCMV infection in mice. In this study, we observed that NK cells exerted minimal to no impact on vaccine-elicited T cells following LCMV challenge, suggesting that adenovirus vaccine-elicited T cells may be less subject to NK cell regulation. These data contribute to our understanding of NK cell regulatory functions and T cell-based vaccines.\n","tags":null,"title":"Adenovirus Vector Vaccination Impacts NK Cell Rheostat Function following Lymphocytic Choriomeningitis Virus Infection.\n","type":"publication"},{"authors":["Chettimada","Lorenz","Misra","Dillon","Keith Reeves","Cordelia Manickam","Morgello","Kirk","Mehta","Gabuzda"],"categories":null,"content":"","date":1525132800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1525132800,"objectID":"1b0f91e494e484009b7342f11d3d534e","permalink":"/publication/29740045/","publishdate":"2018-05-01T00:00:00Z","relpermalink":"/publication/29740045/","section":"publication","summary":"Exosomes are nanovesicles released from most cell types including immune cells. Prior studies suggest exosomes play a role in HIV pathogenesis, but little is known about exosome cargo in relation to immune responses and oxidative stress. Here, we characterize plasma exosomes in HIV patients and their relationship to immunological and oxidative stress markers. Plasma exosome fractions were isolated from HIV-positive subjects on ART with suppressed viral load and HIV-negative controls. Exosomes were characterized by electron microscopy, nanoparticle tracking, immunoblotting, and LC-MS/MS proteomics. Plasma exosomes were increased in HIV-positive subjects compared to controls, and correlated with increased oxidative stress markers (cystine, oxidized cys-gly) and decreased PUFA (DHA, EPA, DPA). Untargeted proteomics detected markers of exosomes (CD9, CD63, CD81), immune activation (CD14, CRP, HLA-A, HLA-B), oxidative stress (CAT, PRDX1, PRDX2, TXN), and Notch4 in plasma exosomes. Exosomal Notch4 was increased in HIV-positive subjects versus controls and correlated with immune activation markers. Treatment of THP-1 monocytic cells with patient-derived exosomes induced expression of genes related to interferon responses and immune activation. These results suggest that exosomes in ART-treated HIV patients carry proteins related to immune activation and oxidative stress, have immunomodulatory effects on myeloid cells, and may have pro-inflammatory and redox effects during pathogenesis.\n","tags":null,"title":"Exosome markers associated with immune activation and oxidative stress in HIV patients on antiretroviral therapy.\n","type":"publication"},{"authors":["Hogan","Hanhauser","Hobbs","Palmer","Robles","Stephanie Jost","LaCasce","Abramson","Hamdan","Marty","Kuritzkes","Henrich"],"categories":null,"content":"","date":1525132800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1525132800,"objectID":"78e8cbde43c469adaa46e82856620294","permalink":"/publication/29746555/","publishdate":"2018-05-01T00:00:00Z","relpermalink":"/publication/29746555/","section":"publication","summary":"BACKGROUND: Human Herpes Virus 8 (HHV8) can cause Kaposi's Sarcoma (KS) in immunosuppressed individuals. However, little is known about the association between chemotherapy or hematopoietic stem cell transplantation (HSCT), circulating HHV8 DNA levels, and clinical KS in HIV-1-infected individuals with various malignancies. Therefore, we examined the associations between various malignancies, systemic cancer chemotherapy, T cell phenotypes, and circulating HHV8 DNA in 29 HIV-1-infected participants with concomitant KS or other cancer diagnoses.\n      METHODS: We quantified HHV8 plasma viral loads and cell-associated HHV8 DNA and determined the relationship between circulating HHV8 DNA and lymphocyte counts, and markers of early and late lymphocyte activation, proliferation and exhaustion.\n      RESULTS: There were no significant differences in plasma HHV8 DNA levels between baseline and post-chemotherapy time points or with the presence or absence of clinical KS. However, in two participants circulating HHV8 DNA increased following treatment for KS or HSCT for lymphoma,. We observed an approximately 2-log10 reduction in plasma HHV8 DNA in an individual with KS and multicentric Castleman disease following rituximab monotherapy. Although individuals with clinical KS had lower mean CD4+ T cell counts and percentages as expected, there were no significant associations with these factors and plasma HHV8 levels. We identified increased proportions of CD8+ and CD4+ T cells expressing CD69 (P = 0.01 \u0026 P = 0.04 respectively), and increased CD57 expression on CD4+ T cells (P = 0.003) in participants with detectable HHV8.\n      CONCLUSION: These results suggest there is a complex relationship between circulating HHV8 DNA and tissue-based disease in HIV-1 and HHV8 co-infected individuals with various malignancies.\n","tags":null,"title":"Human Herpes Virus 8 in HIV-1 infected individuals receiving cancer chemotherapy and stem cell transplantation.\n","type":"publication"},{"authors":["Daniel Ram","Cordelia Manickam","Brady Hueber","Itell","Permar","Valerie Varner","Keith Reeves"],"categories":null,"content":"","date":1525132800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1525132800,"objectID":"658e39f598a2bef601ecc692b2514714","permalink":"/publication/29851983/","publishdate":"2018-05-01T00:00:00Z","relpermalink":"/publication/29851983/","section":"publication","summary":"Natural killer (NK) cells classically typify the nonspecific effector arm of the innate immune system, but have recently been shown to possess memory-like properties against multiple viral infections, most notably CMV. Expression of the activating receptor NKG2C is elevated on human NK cells in response to infection with CMV as well as HIV, and may delineate cells with memory and memory-like functions. A better understanding of how NKG2C+ NK cells specifically respond to these pathogens could be significantly advanced using nonhuman primate (NHP) models but, to date, it has not been possible to distinguish NKG2C from its inhibitory counterpart, NKG2A, in NHP because of unfaithful antibody cross-reactivity. Using novel RNA-based flow cytometry, we identify for the first time true memory NKG2C+ NK cells in NHP by gene expression (KLRC2), and show that these cells have elevated frequencies and diversify their functional repertoire specifically in response to rhCMV and SIV infections.\n","tags":null,"title":"Tracking KLRC2 (NKG2C)+ memory-like NK cells in SIV+ and rhCMV+ rhesus macaques.\n","type":"publication"},{"authors":["Huot","Bosinger","Paiardini","Keith Reeves","Mller-Trutwin"],"categories":null,"content":"","date":1522540800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1522540800,"objectID":"98590ccc3873d14737c606bc62400743","permalink":"/publication/29725327/","publishdate":"2018-04-01T00:00:00Z","relpermalink":"/publication/29725327/","section":"publication","summary":"Combined antiretroviral therapies (cARTs) efficiently control HIV replication leading to undetectable viremia and drastic increases in lifespan of people living with HIV. However, cART does not cure HIV infection as virus persists in cellular and anatomical reservoirs, from which the virus generally rebounds soon after cART cessation. One major anatomical reservoir are lymph node (LN) follicles, where HIV persists through replication in follicular helper T cells and is also trapped by follicular dendritic cells. Natural hosts of SIV, such as African green monkeys and sooty mangabeys, generally do not progress to disease although displaying persistently high viremia. Strikingly, these hosts mount a strong control of viral replication in LN follicles shortly after peak viremia that lasts throughout infection. Herein, we discuss the potential interplay between viral control in LNs and the resolution of inflammation, which is characteristic for natural hosts. We furthermore detail the differences that exist between non-pathogenic SIV infection in natural hosts and pathogenic HIV/SIV infection in humans and macaques regarding virus target cells and replication dynamics in LNs. Several mechanisms have been proposed to be implicated in the strong control of viral replication in natural host's LNs, such as NK cell-mediated control, that will be reviewed here, together with lessons and limitations of in vivo cell depletion studies that have been performed in natural hosts. Finally, we discuss the impact that these insights on viral dynamics and host responses in LNs of natural hosts have for the development of strategies toward HIV cure.\n","tags":null,"title":"Lymph Node Cellular and Viral Dynamics in Natural Hosts and Impact for HIV Cure Strategies.\n","type":"publication"},{"authors":["Autissier","Li","Goepfert","Keith Reeves"],"categories":null,"content":"","date":1519862400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1519862400,"objectID":"e397f4c14d310eafdcbd1f63fff48295","permalink":"/publication/29486582/","publishdate":"2018-03-01T00:00:00Z","relpermalink":"/publication/29486582/","section":"publication","summary":"Apoptotic membrane microparticles (MMPs) derived from dying cells of multiple cell origins are highly immunostimulatory and are indicative of global immune activation and cell death in a variety of diseases. In this study, we developed a flow cytometric bead assay to quantify annexin-V+ apoptotic (MMPs) in plasma from humans and rhesus macaques. With a combination of flow cytometry and pan-fluorescent beads, MMPs were enumerated in plasma specimens by adding a constant ratio of beads to initial fluid volumes and then calculating MMP/mL based on MMP-to-bead ratios. Using this straightforward assay, we found that circulating MMP quantifications were highly reproducible and similar in number between normal rhesus macaques and humans subjects. However, MMPs increased two- to threefold during HIV and simian immunodeficiency virus (SIV) infections and were positively associated with T cell immune activation. Collectively, we present a rapid bead-based assay for both humans and macaque models to quantify MMPs that could be an instigator and predictor of immune activation, which is a primary source of HIV/SIV disease.\n","tags":null,"title":"Short Communication: Apoptotic Membrane Microparticles Quantified by Fluorescent Bead-Based Assay Are Elevated in HIV and SIV Infections.\n","type":"publication"},{"authors":["Spandan Shah","Cordelia Manickam","Daniel Ram","Keith Reeves"],"categories":null,"content":"","date":1512086400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1512086400,"objectID":"913c08789ddb048ab76e8d7558f7861e","permalink":"/publication/29326704/","publishdate":"2017-12-01T00:00:00Z","relpermalink":"/publication/29326704/","section":"publication","summary":"Over the past several years, new populations of innate lymphocytes have been described in mice and primates that are critical for mucosal homeostasis, microbial regulation, and immune defense. Generally conserved from mice to humans, innate lymphoid cells (ILC) have been divided primarily into three subpopulations based on phenotypic and functional repertoires: ILC1 bear similarities to natural killer cells; ILC2 have overlapping functions with TH2 cells; and ILC3 that share many functions with TH17/TH22 cells. ILC are specifically enriched at mucosal surfaces and are possibly one of the earliest responders during viral infections besides being involved in the homeostasis of gut-associated lymphoid tissue and maintenance of gut epithelial barrier integrity. Burgeoning evidence also suggests that there is an early and sustained abrogation of ILC function and numbers during HIV and pathogenic SIV infections, most notably ILC3 in the gastrointestinal tract, which leads to disruption of the mucosal barrier and dysregulation of the local immune system. A better understanding of the direct or indirect mechanisms of loss and dysfunction will be critical to immunotherapeutics aimed at restoring these cells. Herein, we review the current literature on ILC with a particular emphasis on ILC3 and their role(s) in mucosal immunology and the significance of disrupting the ILC niche during HIV and SIV infections.\n","tags":null,"title":"Innate Lymphoid Cells in HIV/SIV Infections.\n","type":"publication"},{"authors":["Cordelia Manickam","Keith Reeves"],"categories":null,"content":"","date":1509494400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1509494400,"objectID":"938c8a7e8a92da538184dd1c327ed068","permalink":"/publication/30123888/","publishdate":"2017-11-01T00:00:00Z","relpermalink":"/publication/30123888/","section":"publication","summary":"PMID: 30123888 [PubMed]\n","tags":null,"title":"A mouse model for hepatitis C virus infection: are we there yet?\n","type":"publication"},{"authors":["Huot","Jacquelin","Garcia-Tellez","Philippe Rascle","Ploquin","Madec","Keith Reeves","Derreudre-Bosquet","Mller-Trutwin"],"categories":null,"content":"","date":1506816000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1506816000,"objectID":"3d447b3c4975271fb09c6a0d16c89d11","permalink":"/publication/29035370/","publishdate":"2017-10-01T00:00:00Z","relpermalink":"/publication/29035370/","section":"publication","summary":"Natural killer (NK) cells play an essential role in antiviral immunity, but knowledge of their function in secondary lymphoid organs is incomplete. Lymph node follicles constitute a major viral reservoir during infections with HIV-1 and simian immunodeficiency virus of macaques (SIVmac). In contrast, during nonpathogenic infection with SIV from African green monkeys (SIVagm), follicles remain generally virus free. We show that NK cells in secondary lymphoid organs from chronically SIVagm-infected African green monkeys (AGMs) were frequently CXCR5+ and entered and persisted in lymph node follicles throughout the follow-up (240 d post-infection). These follicles were strongly positive for IL-15, which was primarily presented in its membrane-bound form by follicular dendritic cells. NK cell depletion through treatment with anti-IL-15 monoclonal antibody during chronic SIVagm infection resulted in high viral replication rates in follicles and the T cell zone and increased viral DNA in lymph nodes. Our data suggest that, in nonpathogenic SIV infection, NK cells migrate into follicles and play a major role in viral reservoir control in lymph nodes.\n","tags":null,"title":"Natural killer cells migrate into and control simian immunodeficiency virus replication in lymph node follicles in African green monkeys.\n","type":"publication"},{"authors":["Cordelia Manickam","Martinot","Rhianna Jones","Valerie Varner","Keith Reeves"],"categories":null,"content":"","date":1504224000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1504224000,"objectID":"bef76571d460b74e7a5863df98e14b43","permalink":"/publication/28915405/","publishdate":"2017-09-01T00:00:00Z","relpermalink":"/publication/28915405/","section":"publication","summary":"Despite drug advances for Hepatitis C virus (HCV), re-infections remain prevalent in high-risk populations. Unfortunately, the role of preexisting viral immunity and how it modulates re-infection is unclear. GBV-B infection of common marmosets is a useful model to study tissue immune responses in hepacivirus infections, and in this study we re-challenged 4 animals after clearance of primary viremia. Although only low-to-absent viremia was observed following re-challenge, GBV-B viral RNA was detectable in liver, confirming re-infection. Microscopic hepatic lesions indicated severe-to-mild lymphocyte infiltration and fibrosis in 3 out of 4 animals. Further, GBV-B-specific T cells were elevated in animals with moderate-to-severe hepatopathology, and up to 3-fold increases in myeloid dendritic and activated natural killer cells were observed after infection. Our data indicate that occult hepacivirus re-infections occur and that new liver pathology is possible even in the presence of anti-hepacivirus T cells and in the absence of high viremia.\n","tags":null,"title":"Hepatic immunopathology during occult hepacivirus re-infection.\n","type":"publication"},{"authors":["Paust","Blish","Keith Reeves"],"categories":null,"content":"","date":1504224000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1504224000,"objectID":"2ff421064f8c061e0e103f60a240dd1e","permalink":"/publication/28794018/","publishdate":"2017-09-01T00:00:00Z","relpermalink":"/publication/28794018/","section":"publication","summary":"Classically, natural killer (NK) cells have been defined by nonspecific innate killing of virus-infected and tumor cells. However, burgeoning evidence suggests that the functional repertoire of NK cells is far more diverse than has been previously appreciated, thus raising the possibility that there may be unexpected functional specialization and even adaptive capabilities among NK cell subpopulations. Some of the first evidence that NK cells respond in an antigen-specific fashion came from experiments revealing that subpopulations of murine NK cells were able to respond to a specific murine cytomegalovirus (MCMV) protein and that in the absence of T and B cells, murine NK cells also mediated adaptive immune responses to a secondary challenge with specific haptens. These data have been followed by demonstrations of NK cell memory of viruses and viral antigens in mice and primates. Herein, we discuss different forms of NK cell antigen specificity and how these responses may be tuned to specific viral pathogens, and we provide assessment of the current literature that may explain molecular mechanisms of the novel phenomenon of NK cell memory.\n","tags":null,"title":"Redefining Memory: Building the Case for Adaptive NK Cells.\n","type":"publication"},{"authors":["Krner","Simoneau","Schommers","Granoff","Ziegler","Hlzemer","Lunemann","Chukwukelu","Corleis","Naranbhai","Kwon","Scully","Stephanie Jost","Kirchhoff","Carrington","Altfeld"],"categories":null,"content":"","date":1498867200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1498867200,"objectID":"cd8efa509270337f8bdf4b4e02413f79","permalink":"/publication/28704647/","publishdate":"2017-07-01T00:00:00Z","relpermalink":"/publication/28704647/","section":"publication","summary":"It was widely accepted that HIV-1 downregulates HLA-A/B to avoid CTL recognition while leaving HLA-C unaltered in order to prevent NK cell activation by engaging inhibitory NK cell receptors, but it was recently observed that most primary isolates of HIV-1 can mediate HLA-C downmodulation. Now we report that HIV-1-mediated downmodulation of HLA-C was associated with reduced binding to its respective inhibitory receptors. Despite this, HLA-C-licensed NK cells displayed reduced antiviral activity compared to their unlicensed counterparts, potentially due to residual binding to the respective inhibitory receptors. Nevertheless, NK cells were able to sense alterations of HLA-C expression demonstrated by increased antiviral activity when exposed to viral strains with differential abilities to downmodulate HLA-C. These results suggest that the capability of HLA-C-licensed NK cells to control HIV-1 replication is determined by the strength of KIR/HLA-C interactions and is thus dependent on both host genetics and the extent of virus-mediated HLA-C downregulation.\n","tags":null,"title":"HIV-1-Mediated Downmodulation of HLA-C Impacts Target Cell Recognition and Antiviral Activity of NK Cells.\n","type":"publication"},{"authors":["Henrich","Hobbs","Hanhauser","Scully","Hogan","Robles","Leadabrand","Marty","Palmer","Stephanie Jost","Krner","Li","Gandhi","Hamdan","Abramson","LaCasce","Kuritzkes"],"categories":null,"content":"","date":1498867200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1498867200,"objectID":"efa3745162e532d8b5cbb4e5edc22e74","permalink":"/publication/28838149/","publishdate":"2017-07-01T00:00:00Z","relpermalink":"/publication/28838149/","section":"publication","summary":"Background: Systemic chemotherapies for various malignancies have been shown to significantly, yet transiently, decrease numbers of CD4+ T lymphocytes, a major reservoir for human immunodeficiency virus type 1 (HIV-1) infection. However, little is known about the impact of cytoreductive chemotherapy on HIV-1 reservoir dynamics, persistence, and immune responses.\n      Methods: We investigated the changes in peripheral CD4+ T-cell-associated HIV-1 DNA and RNA levels, lymphocyte activation, viral population structure, and virus-specific immune responses in a longitudinal cohort of 15 HIV-1-infected individuals receiving systemic chemotherapy or subsequent autologous stem cell transplantation for treatment of hematological malignancies and solid tumors.\n      Results: Despite a transient reduction in CD4+ T cells capable of harboring HIV-1, a 1.7- and 3.3-fold increase in mean CD4+ T-cell-associated HIV-1 RNA and DNA, respectively, were observed months following completion of chemotherapy in individuals on antiretroviral therapy. We also observed changes in CD4+ T-cell population diversity and clonal viral sequence expansion during CD4+ T-cell reconstitution following chemotherapy cessation. Finally, HIV-1 DNA was preferentially, and in some cases exclusively, detected in cytomegalovirus (CMV)- and Epstein-Barr virus (EBV)-responsive CD4+ T cells following chemotherapy.\n      Conclusions: Expansion of HIV-infected CMV/EBV-specific CD4 + T cells may contribute to maintenance of the HIV DNA reservoir following chemotherapy.\n","tags":null,"title":"Human Immunodeficiency Virus Type 1 Persistence Following Systemic Chemotherapy for Malignancy.\n","type":"publication"},{"authors":["Cordelia Manickam","Wachtman","Martinot","Giavedoni","Keith Reeves"],"categories":null,"content":"","date":1483228800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1483228800,"objectID":"8edc389cab0ee291a0ce9b8bd66c52ae","permalink":"/publication/28085952/","publishdate":"2017-01-01T00:00:00Z","relpermalink":"/publication/28085952/","section":"publication","summary":"Chronic hepatitis C has been associated with metabolic syndrome that includes insulin resistance, hepatic steatosis and obesity. These metabolic aberrations are risk factors for disease severity and treatment outcome in infected patients. Experimental infection of marmosets with GBV-B serves as a tangible, small animal model for human HCV infection, and while virology and pathology are well described, a full investigation of clinical disease and the metabolic milieu is lacking. In this study six marmosets were infected intravenously with GBV-B and changes in hematologic, serum biochemical and plasma metabolic measures were investigated over the duration of infection. Infected animals exhibited signs of lymphocytopenia, but platelet and RBC counts were generally stable or even increased. Although most animals showed a transient decline in blood glucose, infection resulted in several fold increases in plasma insulin, glucagon and glucagon-like peptide 1 (GLP-1). All infected animals experienced transient weight loss within the first 28 days of infection, but also became hypertriglyceridemic and had up to 10-fold increases in adipocytokines such as resistin and plasminogen activator inhibitor 1 (PAI-1). In liver, moderate to severe cytoplasmic changes associated with steatotic changes was observed microscopically at 168 days post infection. Collectively, these results suggest that GBV-B infection is accompanied by hematologic, biochemical and metabolic abnormalities that could lead to obesity, diabetes, thrombosis and atherosclerosis, even after virus has been cleared. Our findings mirror those found in HCV patients, suggesting that metabolic syndrome could be conserved among hepaciviruses, and both mechanistic and interventional studies for treating HCV-induced metabolic complications could be evaluated in this animal model.\n","tags":null,"title":"Metabolic Dysregulation in Hepacivirus Infection of Common Marmosets (Callithrix jacchus).\n","type":"publication"},{"authors":["Palmer","Romero-Tejeda","Scully","Lockhart","Seaman","Goldenthal","Piechocka-Trocha","Walker","Chibnik","Stephanie Jost","Porichis"],"categories":null,"content":"","date":1480550400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1480550400,"objectID":"515d47b9d331b721f5e0e9e687e73c58","permalink":"/publication/27938646/","publishdate":"2016-12-01T00:00:00Z","relpermalink":"/publication/27938646/","section":"publication","summary":"INTRODUCTION: An effective prophylactic vaccine against HIV will need to elicit antibody responses capable of recognizing and neutralizing rapidly evolving antigenic regions. The immunologic milieu associated with development of neutralizing antibody breadth remains to be fully defined. In this study, we sought to identify immunological signatures associated with neutralization breadth in HIV controllers. We applied an immune monitoring approach to analyze markers of T cell and myeloid cell activation by flow cytometry, comparing broad neutralizers with low- and non-neutralizers using multivariate and univariate analyses.\n      METHODS: Antibody neutralization breadth was determined, and cryopreserved peripheral blood mononuclear cells were stained for T cell and myeloid cell activation markers. Subjects were grouped according to neutralization breadth, and T cell and myeloid cell activation was analyzed by partial least squares discriminant analysis to determine immune signatures associated with high neutralization breadth.\n      RESULTS: We show that neutralization breadth in HIV viraemic controllers (VC) was strongly associated with increased frequencies of CD8+CD57+ T cells and that this association was independent of viral load, CD4 count and time since HIV diagnosis.\n      CONCLUSIONS: Our data show elevated frequencies of CD8+CD57+ T cells in VC who develop neutralization breadth against HIV. This immune signature could serve as a potential biomarker of neutralization breadth and should be further investigated in other HIV-positive cohorts and in HIV vaccine trials.\n","tags":null,"title":"Increased frequencies of CD8+CD57+ T cells are associated with antibody neutralization breadth against HIV in viraemic controllers.\n","type":"publication"},{"authors":["Adnan","Keith Reeves","Gillis","Wong","Yu","Camp","Li","Connole","Li","Piatak","Lifson","Li","Keele","Kozlowski","Desrosiers","Haase","Johnson"],"categories":null,"content":"","date":1480550400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1480550400,"objectID":"666ca6d33cc3c6f2df3385331208febf","permalink":"/publication/27959961/","publishdate":"2016-12-01T00:00:00Z","relpermalink":"/publication/27959961/","section":"publication","summary":"Defining the correlates of immune protection conferred by SIVnef, the most effective vaccine against SIV challenge, could enable the design of a protective vaccine against HIV infection. Here we provide a comprehensive assessment of immune responses that protect against SIV infection through detailed analyses of cellular and humoral immune responses in the blood and tissues of rhesus macaques vaccinated with SIVnef and then vaginally challenged with wild-type SIV. Despite the presence of robust cellular immune responses, animals at 5 weeks after vaccination displayed only transient viral suppression of challenge virus, whereas all macaques challenged at weeks 20 and 40 post-SIVnef vaccination were protected, as defined by either apparent sterile protection or significant suppression of viremia in infected animals. Multiple parameters of CD8 T cell function temporally correlated with maturation of protection, including polyfunctionality, phenotypic differentiation, and redistribution to gut and lymphoid tissues. Importantly, we also demonstrate the induction of a tissue-resident memory population of SIV-specific CD8 T cells in the vaginal mucosa, which was dependent on ongoing low-level antigenic stimulation. Moreover, we show that vaginal and serum antibody titers inversely correlated with post-challenge peak viral load, and we correlate the accumulation and affinity maturation of the antibody response to the duration of the vaccination period as well as to the SIVnef antigenic load. In conclusion, maturation of SIVnef-induced CD8 T cell and antibody responses, both propelled by viral persistence in the gut mucosa and secondary lymphoid tissues, results in protective immune responses that are able to interrupt viral transmission at mucosal portals of entry as well as potential sites of viral dissemination.\n","tags":null,"title":"Persistent Low-Level Replication of SIVnef Drives Maturation of Antibody and CD8 T Cell Responses to Induce Protective Immunity against Vaginal SIV Infection.\n","type":"publication"},{"authors":["Cordelia Manickam","Rajakumar","Wachtman","Kramer","Martinot","Valerie Varner","Giavedoni","Keith Reeves"],"categories":null,"content":"","date":1472688000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1472688000,"objectID":"3e8aa8b71bb3c1614a0de85b360f3f9c","permalink":"/publication/27489267/","publishdate":"2016-09-01T00:00:00Z","relpermalink":"/publication/27489267/","section":"publication","summary":"UNLABELLED: Despite its importance in shaping adaptive immune responses, viral clearance, and immune-based inflammation, tissue-specific innate immunity remains poorly characterized for hepatitis C virus (HCV) infection due to the lack of access to acutely infected tissues. In this study, we evaluated the impact of natural killer (NK) cells and myeloid (mDCs) and plasmacytoid (pDCs) dendritic cells on control of virus replication and virus-induced pathology caused by another, more rapidly resolving hepacivirus, GB virus B (GBV-B), in infections of common marmosets. High plasma and liver viral loads and robust hepatitis characterized acute GBV-B infection, and while viremia was generally cleared by 2 to 3 months postinfection, hepatitis and liver fibrosis persisted after clearance. Coinciding with peak viral loads and liver pathology, the levels of NK cells, mDCs, and pDCs in the liver increased up to 3-fold. Although no obvious numerical changes in peripheral innate cells occurred, circulating NK cells exhibited increased perforin and Ki67 expression levels and increased surface expression of CXCR3. These data suggested that increased NK cell arming and proliferation as well as tissue trafficking may be associated with influx into the liver during acute infection. Indeed, NK cell frequencies in the liver positively correlated with plasma (R = 0.698; P = 0.015) and liver (R = 0.567; P = 0.057) viral loads. Finally, soluble factors associated with NK cells and DCs, including gamma interferon (IFN-) and RANTES, were increased in acute infection and also were associated with viral loads and hepatitis. Collectively, the findings showed that mobilization of local and circulating innate immune responses was linked to acute virus-induced hepatitis, and potentially to resolution of GBV-B infection, and our results may provide insight into similar mechanisms in HCV infection.\n      IMPORTANCE: Hepatitis C virus (HCV) infection has created a global health crisis, and despite new effective antivirals, it is still a leading cause of liver disease and death worldwide. Recent evidence suggests that innate immunity may be a potential therapeutic target for HCV, but it may also be a correlate of increased disease. Due to a lack of access to human tissues with acute HCV infection, in this study we evaluated the role of innate immunity in resolving infection with a hepacivirus, GBV-B, in common marmosets. Collectively, our data suggest that NK cell and DC mobilization in acute hepacivirus infection can dampen virus replication but also regulate acute and chronic liver damage. How these two opposing effects on the host may be modulated in future therapeutic and vaccine approaches warrants further study.\n","tags":null,"title":"Acute Liver Damage Associated with Innate Immune Activation in a Small Nonhuman Primate Model of Hepacivirus Infection.\n","type":"publication"},{"authors":["Garcia-Beltran","Hlzemer","Martrus","Chung","Pacheco","Simoneau","Rucevic","Lamothe-Molina","Pertel","Kim","Dugan","Alter","Dechanet-Merville","Stephanie Jost","Carrington","Altfeld"],"categories":null,"content":"","date":1467331200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1467331200,"objectID":"c9815fa37c0d3c2763f0dda1d6aa7f4a","permalink":"/publication/27455421/","publishdate":"2016-07-01T00:00:00Z","relpermalink":"/publication/27455421/","section":"publication","summary":"The activating natural killer (NK)-cell receptor KIR3DS1 has been linked to the outcome of various human diseases, including delayed progression of disease caused by human immunodeficiency virus type 1 (HIV-1), yet a ligand that would account for its biological effects has remained unknown. We screened 100 HLA class I proteins and found that KIR3DS1 bound to HLA-F, a result we confirmed biochemically and functionally. Primary human KIR3DS1(+) NK cells degranulated and produced antiviral cytokines after encountering HLA-F and inhibited HIV-1 replication in vitro. Activation of CD4(+) T cells triggered the transcription and surface expression of HLA-F mRNA and HLA-F protein, respectively, and induced binding of KIR3DS1. HIV-1 infection further increased the transcription of HLA-F mRNA but decreased the binding of KIR3DS1, indicative of a mechanism for evading recognition by KIR3DS1(+) NK cells. Thus, we have established HLA-F as a ligand of KIR3DS1 and have demonstrated cell-context-dependent expression of HLA-F that might explain the widespread influence of KIR3DS1 in human disease.\n","tags":null,"title":"Open conformers of HLA-F are high-affinity ligands of the activating NK-cell receptor KIR3DS1.\n","type":"publication"},{"authors":["Hensley-McBain","Zevin","Manuzak","S. Smith","Gile","Miller","Agricola","Katze","Keith Reeves","Kraft","Langevin","Klatt"],"categories":null,"content":"","date":1459468800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1459468800,"objectID":"57a7ad495c1f88db5168d52f883baf1f","permalink":"/publication/26937040/","publishdate":"2016-04-01T00:00:00Z","relpermalink":"/publication/26937040/","section":"publication","summary":"UNLABELLED: An altered intestinal microbiome during chronic human immunodeficiency virus (HIV) infection is associated with mucosal dysfunction, inflammation, and disease progression. We performed a preclinical evaluation of the safety and efficacy of fecal microbiota transplantation (FMT) as a potential therapeutic in HIV-infected individuals. Antiretroviral-treated, chronically simian immunodeficiency virus (SIV)-infected rhesus macaques received antibiotics followed by FMT. The greatest microbiota shift was observed after antibiotic treatment. The bacterial community composition at 2 weeks post-FMT resembled the pre-FMT community structure, although differences in the abundances of minor bacterial populations remained. Immunologically, we observed significant increases in the number of peripheral Th17 and Th22 cells and reduced CD4(+) T cell activation in gastrointestinal tissues post-FMT. Importantly, the transplant was well tolerated with no negative clinical side effects. Although this pilot study did not control for the differential contributions of antibiotic treatment and FMT to the observed results, the data suggest that FMT may have beneficial effects that should be further evaluated in larger studies.\n      IMPORTANCE: Due to the immunodeficiency and chronic inflammation that occurs during HIV infection, determination of the safety of FMT is crucial to prevent deleterious consequences if it is to be used as a treatment in the future. Here we used the macaque model of HIV infection and performed FMT on six chronically SIV-infected rhesus macaques on antiretroviral treatment. In addition to providing a preclinical demonstration of the safety of FMT in primates infected with a lentivirus, this study provided a unique opportunity to examine the relationships between alterations to the microbiome and immunological parameters. In this study, we found increased numbers of Th17 and Th22 cells as well as decreased activation of CD4(+) T cells post-FMT, and these changes correlated most strongly across all sampling time points with lower-abundance taxonomic groups and other taxonomic groups in the colon. Overall, these data provide evidence that changes in the microbiome, particularly in terms of diversity and changes in minor populations, can enhance immunity and do not have adverse consequences.\n","tags":null,"title":"Effects of Fecal Microbial Transplantation on Microbiome and Immunity in Simian Immunodeficiency Virus-Infected Macaques.\n","type":"publication"},{"authors":["Manuzak","Hensley-McBain","Zevin","Miller","Cubas","Agricola","Gile","Richert-Spuhler","Patilea","Estes","Langevin","Keith Reeves","Haddad","Klatt"],"categories":null,"content":"","date":1451606400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1451606400,"objectID":"a8a9dba1280018411ab30eb35d818b6e","permalink":"/publication/26826246/","publishdate":"2016-01-01T00:00:00Z","relpermalink":"/publication/26826246/","section":"publication","summary":"Given the critical role of mucosal surfaces in susceptibility to infection, it is imperative that effective mucosal responses are induced when developing efficacious vaccines and prevention strategies for infection. Modulating the microbiota in the gastrointestinal (GI) tract through the use of probiotics (PBio) is a safe and well-tolerated approach to enhance mucosal and overall health. We assessed the longitudinal impact of daily treatment with the VSL#3 probiotic on cellular and humoral immunity and inflammation in healthy macaques. PBio therapy resulted in significantly increased frequencies of B cells expressing IgA in the colon and lymph node (LN), likely because of significantly increased LN T follicular helper cell frequencies and LN follicles. Increased frequencies of IL-23(+) APCs in the colon were found post-PBio treatment, which correlated with LN T follicular helper cells. Finally, VSL#3 significantly downmodulated the response of TLR2-, TLR3-, TLR4-, and TLR9-expressing HEK293 cells to stimulation with Pam3CSK4, polyinosinic-polycytidylic acid, LPS, and ODN2006, respectively. These data provide a mechanism for the beneficial impact of PBio on mucosal health and implicates the use of PBio therapy in the context of vaccination or preventative approaches to enhance protection from mucosal infection by improving immune defenses at the mucosal portal of entry.\n","tags":null,"title":"Enhancement of Microbiota in Healthy Macaques Results in Beneficial Modulation of Mucosal and Systemic Immune Function.\n","type":"publication"},{"authors":["Salzberger","Garcia-Beltran","Dugan","Gubbala","Simoneau","Gressens","Stephanie Jost","Altfeld"],"categories":null,"content":"","date":1448928000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1448928000,"objectID":"19a3dae88f41f4fd13dd62c01fbd57e5","permalink":"/publication/26680341/","publishdate":"2015-12-01T00:00:00Z","relpermalink":"/publication/26680341/","section":"publication","summary":"Viral infections can affect the glycosylation pattern of glycoproteins involved in antiviral immunity. Given the importance of protein glycosylation for immune function, we investigated the effect that modulation of the highly conserved HLA class I N-glycan has on KIR:HLA interactions and NK cell function. We focused on HLA-B*57:01 and its interaction with KIR3DL1, which has been shown to play a critical role in determining the progression of a number of human diseases, including human immunodeficiency virus-1 infection. 721.221 cells stably expressing HLA-B*57:01 were treated with a panel of glycosylation enzyme inhibitors, and HLA class I expression and KIR3DL1 binding was quantified. In addition, the functional outcomes of HLA-B*57:01 N-glycan disruption/modulation on KIR3DL1+ Jurkat reporter cells and primary human KIR3DL1+ NK cells was assessed. Different glycosylation enzyme inhibitors had varying effects on HLA-B*57:01 expression and KIR3DL1-Fc binding. The most remarkable effect was that of tunicamycin, an inhibitor of the first step of N-glycosylation, which resulted in significantly reduced KIR3DL1-Fc binding despite sustained expression of HLA-B*57:01 on 721.221 cells. This effect was paralleled by decreased activation of KIR3DL1+ Jurkat reporter cells, as well as increased degranulation of primary human KIR3DL1+ NK cell clones when encountering HLA-B*57:01-expressing 721.221 cells that were pre-treated with tunicamycin. Overall, these results demonstrate that N-glycosylation of HLA class I is important for KIR:HLA binding and has an impact on NK cell function.\n","tags":null,"title":"Influence of Glycosylation Inhibition on the Binding of KIR3DL1 to HLA-B*57:01.\n","type":"publication"},{"authors":["Palmer","Romero-Tejeda","Sirignano","Sharma","Allen","Altfeld","Stephanie Jost"],"categories":null,"content":"","date":1448928000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1448928000,"objectID":"ea2dacac4969def87738cf912dccd032","permalink":"/publication/26643479/","publishdate":"2015-12-01T00:00:00Z","relpermalink":"/publication/26643479/","section":"publication","summary":"Multiple studies have shown correlates of immune activation with microbial translocation and plasma LPS during HIV infection. It is unclear whether this activation is due to LPS, residual viral replication, or both. Few studies have addressed the effects of persistent in vivo levels of LPS on specific immune functions in humans in the absence of chronic viral infection or pathological settings such as sepsis. We previously reported on a cohort of HIV-negative men with subclinical endotoxemia linked to alterations in CD4/CD8 T cell ratio and plasma cytokine levels. This HIV-negative cohort allowed us to assess cellular immune functions in the context of different subclinical plasma LPS levels ex vivo without confounding viral effects. By comparing two samples of differing plasma LPS levels from each individual, we now show that subclinical levels of plasma LPS in vivo significantly alter T cell proliferative capacity, monocyte cytokine release, and HLA-DR expression, and induce TLR cross-tolerance by decreased phosphorylation of MAPK pathway components. Using this human in vivo model of subclinical endotoxemia, we furthermore show that plasma LPS leads to constitutive activation of STAT1 through autocrine cytokine signaling, suggesting that subclinical endotoxemia in healthy individuals might lead to significant changes in immune function that have thus far not been appreciated.\n","tags":null,"title":"Naturally Occurring Subclinical Endotoxemia in Humans Alters Adaptive and Innate Immune Functions through Reduced MAPK and Increased STAT1 Phosphorylation.\n","type":"publication"},{"authors":["Henrich","Hanhauser","Harrison","Palmer","Romero-Tejeda","Stephanie Jost","Bosch","Kuritzkes"],"categories":null,"content":"","date":1443657600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1443657600,"objectID":"36794e41ed98dafb951c23eaacc0436e","permalink":"/publication/26512140/","publishdate":"2015-10-01T00:00:00Z","relpermalink":"/publication/26512140/","section":"publication","summary":"We conducted a case-controlled study of the associations of CCR5-32 heterozygosity with human immunodeficiency virus type 1 (HIV-1) reservoir size, lymphocyte activation, and CCR5 expression in 114 CCR5(32/WT) and 177 wild-type CCR5 AIDS Clinical Trials Group participants receiving suppressive antiretroviral therapy. Overall, no significant differences were found between groups for any of these parameters. However, higher levels of CCR5 expression correlated with lower amounts of cell-associated HIV-1 RNA. The relationship between CCR5-32 heterozygosity, CCR5 expression, and markers of HIV-1 persistence is likely to be complex and may be influenced by factors such as the duration of ART.\n","tags":null,"title":"CCR5-32 Heterozygosity, HIV-1 Reservoir Size, and Lymphocyte Activation in Individuals Receiving Long-term Suppressive Antiretroviral Therapy.\n","type":"publication"},{"authors":["Schafer","Mller-Trutwin","Keith Reeves"],"categories":null,"content":"","date":1441065600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1441065600,"objectID":"45d1b640f4be729e7cdff089ed633d13","permalink":"/publication/26392410/","publishdate":"2015-09-01T00:00:00Z","relpermalink":"/publication/26392410/","section":"publication","summary":"PMID: 26392410 [PubMed - indexed for MEDLINE]\n","tags":null,"title":"NK cell exhaustion: bad news for chronic disease?\n","type":"publication"},{"authors":["Evans","Li","Schafer","Klatt","Hao","Traslavina","Estes","Brenchley","Keith Reeves"],"categories":null,"content":"","date":1438387200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1438387200,"objectID":"8dd50fd9432007ba93fcde854db04826","permalink":"/publication/26238685/","publishdate":"2015-08-01T00:00:00Z","relpermalink":"/publication/26238685/","section":"publication","summary":"Disruption of the mucosal epithelium during lentivirus infections permits translocation of microbial products into circulation, causing immune activation and driving disease. Although the liver directly filters blood from the intestine and is the first line of defense against gut-derived antigens, the effects of microbial products on the liver are unclear. In livers of normal macaques, minute levels of bacterial products were detectable, but increased 20-fold in simian immunodeficiency virus (SIV)-infected animals. Increased microbial products in the liver induced production of the chemoattractant CXCL16 by myeloid dendritic cells (mDCs), causing subsequent recruitment of hypercytotoxic natural killer (NK) cells expressing the CXCL16 receptor, CXCR6. Microbial accumulation, mDC activation, and cytotoxic NK cell frequencies were significantly correlated with markers of liver damage, and SIV-infected animals consistently had evidence of hepatitis and fibrosis. Collectively, these data indicate that SIV-associated accumulation of microbial products in the liver initiates a cascade of innate immune activation, resulting in liver damage.\n","tags":null,"title":"SIV-induced Translocation of Bacterial Products in the Liver Mobilizes Myeloid Dendritic and Natural Killer Cells Associated With Liver Damage.\n","type":"publication"},{"authors":["Keith Reeves","Li","Stephanie Jost","Blass","Li","Schafer","Valerie Varner","Cordelia Manickam","Eslamizar","Altfeld","von","Barouch"],"categories":null,"content":"","date":1435708800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1435708800,"objectID":"08a65de58625fa210131e70129a36398","permalink":"/publication/26193080/","publishdate":"2015-07-01T00:00:00Z","relpermalink":"/publication/26193080/","section":"publication","summary":"Natural killer (NK) cells have traditionally been considered nonspecific components of innate immunity, but recent studies have shown features of antigen-specific memory in mouse NK cells. However, it has remained unclear whether this phenomenon also exists in primates. We found that splenic and hepatic NK cells from SHIV(SF162P3)-infected and SIV(mac251)-infected macaques specifically lysed Gag- and Env-pulsed dendritic cells in an NKG2-dependent fashion, in contrast to NK cells from uninfected macaques. Moreover, splenic and hepatic NK cells from Ad26-vaccinated macaques efficiently lysed antigen-matched but not antigen-mismatched targets 5 years after vaccination. These data demonstrate that robust, durable, antigen-specific NK cell memory can be induced in primates after both infection and vaccination, and this finding could be important for the development of vaccines against HIV-1 and other pathogens.\n","tags":null,"title":"Antigen-specific NK cell memory in rhesus macaques.\n","type":"publication"},{"authors":["Schafer","Li","Evans","Estes","Keith Reeves"],"categories":null,"content":"","date":1427846400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1427846400,"objectID":"a72fc722898ccb63bb7634b00e0be5fe","permalink":"/publication/25903330/","publishdate":"2015-04-01T00:00:00Z","relpermalink":"/publication/25903330/","section":"publication","summary":"UNLABELLED: Recent evidence suggests that even in treated infections, human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV) replication may continue in lymph nodes (LN), serving as a potential virus reservoir. Here we investigated the effects of lentivirus infection on natural killer (NK) cell frequencies, phenotypes, and functions in naive and acutely or chronically SIVmac239-infected rhesus macaques. Compared to that in naive animals, we observed a 3-fold-greater frequency of cytotoxic CD16(+) CD56(-) NK cells in LN of chronically infected macaques. However, NK cells did not appear to be trafficking to LN, as homing markers CD62L and CCR7 did not increase on circulating NK cells during infection. LN NK cells demonstrated enhanced cytotoxicity in acute infection, with 2-fold increases in perforin expression and 3-fold increases in CD107a expression following mitogen stimulation. Lysis of K562 cells by LN NK cells from acutely infected animals was greater than lysis by preinfection samples from the same animals. LN NK cells from chronically infected animals lysed K562 cells more efficiently than LN NK cells from uninfected animals, but importantly, surrogate markers of cytotoxicity in infected macaques were disproportionately greater than ex vivo killing. Furthermore, Tim-3, an indicator of activation and/or exhaustion, was upregulated 3-fold on LN NK cells in chronically infected animals. Collectively, these data suggest that LN NK cells are skewed toward a cytotoxic phenotype during SIV infection but may become dysfunctional and exhausted in chronic disease.\n      IMPORTANCE: The accumulation of CD16(+) CD56(-) NK cells in the SIV-infected lymph node without changes in NK homing to the LN could suggest that these cells are differentiating in situ. Surprisingly, this increase in frequency of the cytotoxic subset of NK cells is not accompanied by an increase of similar magnitude in the cytolytic function of LN lymphocytes. This functional modulation, together with the higher Tim-3 expression observed on LN NK cells isolated from chronically infected animals than on those from naive macaques, is indicative of an exhausted phenotype. This exhaustion could contribute to the robust replication of HIV and SIV in the LN during acute and chronic stages of infection, allowing the survival of infected cells and maintenance of a viral reservoir.\n","tags":null,"title":"Accumulation of Cytotoxic CD16+ NK Cells in Simian Immunodeficiency Virus-Infected Lymph Nodes Associated with In Situ Differentiation and Functional Anergy.\n","type":"publication"},{"authors":["Billingsley","Rajakumar","Connole","Salisch","Adnan","Kuzmichev","Hong","Keith Reeves","Kang","Li","Li","Haase","Johnson"],"categories":null,"content":"","date":1425168000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1425168000,"objectID":"5ee22c4c8dfcd6b433999d9e668dbf45","permalink":"/publication/25768938/","publishdate":"2015-03-01T00:00:00Z","relpermalink":"/publication/25768938/","section":"publication","summary":"The onset of protective immunity against pathogenic SIV challenge in SIVnef-vaccinated macaques is delayed for 15-20 weeks, a process that is related to qualitative changes in CD8+ T cell responses induced by SIVnef. As a novel approach to characterize cell differentiation following vaccination, we used multi-target qPCR to measure transcription factor expression in nave and memory subsets of CD8++ T cells, and in SIV-specific CD8+ T cells obtained from SIVnef-vaccinated or wild type SIVmac239-infected macaques. Unsupervised clustering of expression profiles organized nave and memory CD8+ T cells into groups concordant with cell surface phenotype. Transcription factor expression patterns in SIV-specific CD8+ T cells in SIVnef-vaccinated animals were distinct from those observed in purified CD8+ T cell subsets obtained from nave animals, and were intermediate to expression profiles of purified central memory and effector memory T cells. Expression of transcription factors elicited by SIVnef vaccination also varied over time: cells obtained at later time points, temporally associated with greater protection, appeared more central-memory like than cells obtained at earlier time points, which appeared more effector memory-like. Expression of transcription factors associated with effector differentiation, such as ID2 and RUNX3, were decreased over time, while expression of transcription factors associated with quiescence or memory differentiation, such as TCF7, BCOR and EOMES, increased. CD8+ T cells specific for a more conserved epitope expressed higher levels of TBX21 and BATF, and appeared more effector-like than cells specific for an escaped epitope, consistent with continued activation by replicating vaccine virus. These data suggest transcription factor expression profiling is a novel method that can provide additional data complementary to the analysis of memory cell differentiation based on classical phenotypic markers. Additionally, these data support the hypothesis that ongoing stimulation by SIVnef promotes a distinct protective balance of CD8+ T cell differentiation and activation states.\n","tags":null,"title":"Characterization of CD8+ T cell differentiation following SIVnef vaccination by transcription factor expression profiling.\n","type":"publication"},{"authors":["Adnan","Colantonio","Yu","Gillis","Wong","Becker","Piatak","Keith Reeves","Lifson","O'Connor","Johnson"],"categories":null,"content":"","date":1422748800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1422748800,"objectID":"b83d052b7fc303c71a2971d0de5a9656","permalink":"/publication/25688559/","publishdate":"2015-02-01T00:00:00Z","relpermalink":"/publication/25688559/","section":"publication","summary":"The live attenuated simian immunodeficiency virus (LASIV) vaccine SIVnef is one of the most effective vaccines in inducing protection against wild-type lentiviral challenge, yet little is known about the mechanisms underlying its remarkable protective efficacy. Here, we exploit deep sequencing technology and comprehensive CD8 T cell epitope mapping to deconstruct the CD8 T cell response, to identify the regions of immune pressure and viral escape, and to delineate the effect of epitope escape on the evolution of the CD8 T cell response in SIVnef-vaccinated animals. We demonstrate that the initial CD8 T cell response in the acute phase of SIVnef infection is mounted predominantly against more variable epitopes, followed by widespread sequence evolution and viral escape. Furthermore, we show that epitope escape expands the CD8 T cell repertoire that targets highly conserved epitopes, defined as anentropic specificity, and generates de novo responses to the escaped epitope variants during the vaccination period. These results correlate SIVnef-induced protection with expanded anentropic specificity and increased response depth. Importantly, these findings render SIVnef, long the gold standard in HIV/SIV vaccine research, as a proof-of-concept vaccine that highlights the significance of the twin principles of anentropic specificity and repertoire depth in successful vaccine design.\n","tags":null,"title":"CD8 T cell response maturation defined by anentropic specificity and repertoire depth correlates with SIVnef-induced protection.\n","type":"publication"},{"authors":["Li","Evans","Gillis","Connole","Keith Reeves"],"categories":null,"content":"","date":1417392000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1417392000,"objectID":"5b9eeb80fb399fdd08150bcfca9e2131","permalink":"/publication/25489000/","publishdate":"2014-12-01T00:00:00Z","relpermalink":"/publication/25489000/","section":"publication","summary":"Plasmacytoid dendritic cells (pDCs), a primary source of interferon  (IFN-), provide a first line of innate immune defense against human immunodeficiency virus infection. However, their kinetics and functions during acute infection are poorly understood. In mucosal tissues of normal rhesus macaques, we found CD4(+) pDCs to be the subset responsible for most IFN- and tumor necrosis factor  (TNF-) production in response to Toll-like receptor (TLR) 7/8 stimulation, compared with relatively anergic CD4(-) pDCs. During acute simian immunodeficiency virus (SIV) infection, gut homing was imprinted on pDCs in the bone marrow, resulting in a decline in pDCs from circulation and secondary lymphoid tissues. Although the accumulated pDCs in the gut mucosae had robust cytokine responses to TLR7/8 stimulation in vitro, pDC gut migration occurred after infection and detection of SIV in plasma. Our data suggest that innate pDC responses do not control initial SIV seeding and dissemination but instead may contribute to ongoing immune activation in the gut.\n","tags":null,"title":"Bone marrow-imprinted gut-homing of plasmacytoid dendritic cells (pDCs) in acute simian immunodeficiency virus infection results in massive accumulation of hyperfunctional CD4+ pDCs in the mucosae.\n","type":"publication"},{"authors":["Keith Reeves","Kang","Li","Li"],"categories":null,"content":"","date":1417392000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1417392000,"objectID":"eee8d516ad5a45d7421d470f5c12c2a5","permalink":"/publication/25469593/","publishdate":"2014-12-01T00:00:00Z","relpermalink":"/publication/25469593/","section":"publication","summary":"PMID: 25469593 [PubMed - indexed for MEDLINE]\n","tags":null,"title":"Depletion of lamina propria innate lymphoid cells in simian immunodeficiency virus infection.\n","type":"publication"},{"authors":["Li","Richert-Spuhler","Evans","Gillis","Connole","Estes","Keele","Klatt","Keith Reeves"],"categories":null,"content":"","date":1417392000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1417392000,"objectID":"c8b903409dc8df6013628e1b3fdbab5a","permalink":"/publication/25503264/","publishdate":"2014-12-01T00:00:00Z","relpermalink":"/publication/25503264/","section":"publication","summary":"HIV/SIV infections break down the integrity of the gastrointestinal mucosa and lead to chronic immune activation and associated disease progression. Innate lymphoid cells (ILCs), distinguishable by high expression of NKp44 and RORt, play key roles in mucosal defense and homeostasis, but are depleted from gastrointestinal (GI) tract large bowel during chronic SIV infection. However, less is known about the kinetics of ILC loss, or if it occurs systemically. In acute SIV infection, we found a massive, up to 8-fold, loss of NKp44+ILCs in all mucosae as early as day 6 post-infection, which was sustained through chronic disease. Interestingly, no loss of ILCs was observed in mucosa-draining lymph nodes. In contrast, classical NK cells were not depleted either from gut or draining lymph nodes. Both ILCs and NK cells exhibited significantly increased levels of apoptosis as measured by increased Annexin-V expression, but while classical NK cells also showed increased proliferation, ILCs did not. Interestingly, ILCs, which are normally noncytolytic, dramatically upregulated cytotoxic functions in acute and chronic infection and acquired a polyfunctional phenotype secreting IFN-, MIP1-, and TNF-, but decreased production of the prototypical cytokine, IL-17. Classical NK cells had less dramatic functional change, but upregulated perforin expression and increased cytotoxic potential. Finally, we show that numerical and functional loss of ILCs was due to increased apoptosis and ROR t suppression induced by inflammatory cytokines in the gut milieu. Herein we demonstrate the first evidence for acute, systemic, and permanent loss of mucosal ILCs during SIV infection associated with reduction of IL-17. The massive reduction of ILCs involves apoptosis without compensatory de novo development/proliferation, but the full mechanism of depletion and the impact of functional change so early in infection remain unclear.\n","tags":null,"title":"Hypercytotoxicity and rapid loss of NKp44+ innate lymphoid cells during acute SIV infection.\n","type":"publication"},{"authors":["Cordelia Manickam","Keith Reeves"],"categories":null,"content":"","date":1417392000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1417392000,"objectID":"f0c17b66472669c1c0b2e346a6df8e30","permalink":"/publication/25538700/","publishdate":"2014-12-01T00:00:00Z","relpermalink":"/publication/25538700/","section":"publication","summary":"Hepatitis C virus (HCV) infection has become a global public health burden costing billions of dollars in health care annually. Even with rapidly advancing scientific technologies this disease still poses a significant threat due to a lack of vaccines and affordable treatment options. The immune correlates of protection and predisposing factors toward chronicity remain major obstacles to development of HCV vaccines and immunotherapeutics due, at least in part, to lack of a tangible infection animal model. This review discusses the currently available animal models for HCV disease with a primary focus on GB virus B (GBV-B) infection of New World primates that recapitulates the dual Hepacivirus phenotypes of acute viral clearance and chronic pathologic disease. HCV and GBV-B are also closely phylogenetically related and advances in characterization of the immune systems of New World primates have already led to the use of this model for drug testing and vaccine trials. Herein, we discuss the benefits and caveats of the GBV-B infection model and discuss potential avenues for future development of novel vaccines and immunotherapies.\n","tags":null,"title":"Modeling HCV disease in animals: virology, immunology and pathogenesis of HCV and GBV-B infections.\n","type":"publication"},{"authors":["Li","Goepfert","Keith Reeves"],"categories":null,"content":"","date":1417392000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1417392000,"objectID":"942ea95b9564748b0788bb745a1bd0d7","permalink":"/publication/25387330/","publishdate":"2014-12-01T00:00:00Z","relpermalink":"/publication/25387330/","section":"publication","summary":"Lentivirus infections are characterized by a dramatic loss of mucosal CD4(+) T cells, breakdown of the gut mucosa, and subsequent chronic immune activation. Residual immune activation persists even in patients controlling virus replication and remains a significant source of ongoing disease morbidities, but the causes are unclear. Plasmacytoid dendritic cells (pDCs), primary producers of interferon (IFN)-, have been previously shown to be depleted from peripheral blood of HIV patients and simian immunodeficiency virus (SIV)-infected macaques, and most recently have been shown to accumulate in the gut mucosa. Although previous work has shown that pDC frequencies can be reduced in the circulation of HIV-1 Elite Controllers, it is unknown if gut-homing also occurs. In this new study we found that during progressive HIV-1 infection pDCs were depleted in peripheral blood compared to seronegative controls, and, correlating with plasma viremia, the remaining pDCs upregulated the gut-homing marker, 47. Even in HIV-1 Elite Controllers pDCs were significantly reduced in blood and 47 expression was still significantly upregulated compared to seronegative controls. Interestingly, pDC trafficking to the gut was associated with increased Ki67 and HLA-DR on circulating CD4(+) and CD8(+) T cells. Overall, these data suggest that gut trafficking of pDCs is independent of virus replication and could be mediated by alternative mechanisms, which in turn could contribute to residual immune activation in HIV-1 Elite Controllers.\n","tags":null,"title":"Short communication: Plasmacytoid dendritic cells from HIV-1 Elite Controllers maintain a gut-homing phenotype associated with immune activation.\n","type":"publication"},{"authors":["George","Hu","Billingsley","Keith Reeves","Sankaran-Walters","Johnson","Dandekar"],"categories":null,"content":"","date":1412121600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1412121600,"objectID":"076b41c7f01c6f161bff0117c68326d7","permalink":"/publication/25282469/","publishdate":"2014-10-01T00:00:00Z","relpermalink":"/publication/25282469/","section":"publication","summary":"Immunization of macaques with attenuated simian immunodeficiency virus (SIV) with deletions in nef (SIVnef) is shown to elicit protective immunity to infection by pathogenic SIV, yet the mechanisms that orchestrate protection and prevent pathogenesis remains unknown. We utilized whole-genome transcriptional profiling to reveal molecular signatures of protective immunity in circulating CD8+ T cells of rhesus macaques vaccinated with SIVmac239nef and challenged with pathogenic SIVmac251. Our findings suggest that protective immunity to pathogenic SIV infection induced by SIVmac239nef is associated with balanced induction of T cell activation and immunoregulatory mechanisms and dampened activation of interferon-induced signaling pathways and cytolytic enzyme production as compared with pathogenic SIVmac251 infection of unvaccinated controls. We provide evidence that protective immunity to SIVmac251 correlates with induction of biomarkers of T cell activation, differentiation, signaling, and adhesion that were down regulated in unvaccinated controls. The study highlights potential immunomodulatory networks associated with protective immunity against the virus.\n","tags":null,"title":"Transcriptional profiling of peripheral CD8+T cell responses to SIVnef and SIVmac251 challenge reveals a link between protective immunity and induction of systemic immunoregulatory mechanisms.\n","type":"publication"},{"authors":["Palmer","Tomassilli","Sirignano","Romero-Tejeda","Arnold","Che","Lauffenburger","Stephanie Jost","Allen","Mayer","Altfeld"],"categories":null,"content":"","date":1409529600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1409529600,"objectID":"8b0f06da4f556609ea107be3035c8206","permalink":"/publication/25003719/","publishdate":"2014-09-01T00:00:00Z","relpermalink":"/publication/25003719/","section":"publication","summary":"This study assessed cellular and soluble markers of immune activation in HIV-1 seronegative MSM. MSM immune profiles were characterized by an increased expression of CD57 on T cells and endotoxemia. Endotoxin presence was linked to recent high-risk exposure and associated with elevated cytokine levels and decreased CD4+/CD8+ T cell ratios. Taken together, these data show elevated levels of inflammation linked to periods of endotoxemia resulting in a significantly different immune phenotype in a subset of MSM at a high risk of HIV-1 acquisition.\n","tags":null,"title":"Enhanced immune activation linked to endotoxemia in HIV-1 seronegative MSM.\n","type":"publication"},{"authors":["Krner","Granoff","Amero","Sirignano","Vaidya","Stephanie Jost","Allen","Rosenberg","Altfeld"],"categories":null,"content":"","date":1406851200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1406851200,"objectID":"94a038d70980079528644cf1dfd68f29","permalink":"/publication/25043727/","publishdate":"2014-08-01T00:00:00Z","relpermalink":"/publication/25043727/","section":"publication","summary":"The acquisition and maintenance of NK-cell function is mediated by inhibitory killer-cell immunoglobulin-like receptors (KIRs) through their interaction with HLA class I molecules. Recently, HLA-C expression levels were shown to be correlated with protection against multiple outcomes of HIV-1 infection; however, the underlying mechanisms are poorly understood. As HLA-C is the natural ligand for the inhibitory receptors KIR2DL1 and KIR2DL2/3, we sought to determine whether HLA-C group haplotypes affect NK-cell responses during primary HIV-1 infection. The phenotypes and functional capacity of NK cells derived from HIV-1-positive and HIV-1-negative individuals were assessed (N = 42 and N = 40, respectively). HIV-1 infection was associated with an increased frequency of KIR2DL1-3(+) NK cells. Further analysis showed that KIR2DL1(+) NK cells were selectively increased in individuals homozygous for HLA-C2, while HLA-C1-homozygous individuals displayed increased proportions of KIR2DL2/3(+) NK cells. KIR2DL1-3(+) NK cells were furthermore more polyfunctional during primary HIV-1 infection in individuals also encoding for their cognate HLA-C group haplotypes, as measured by degranulation and IFN- and TNF- production. These results identify a novel relationship between HLA-C and KIR2DL(+) NK-cell subsets and demonstrate that HLA-C-mediated licensing modulates NK-cell responses to primary HIV-1 infection.\n","tags":null,"title":"Increased frequency and function of KIR2DL1-3 NK cells in primary HIV-1 infection are determined by HLA-C group haplotypes.\n","type":"publication"},{"authors":["Li","Zeng","Duan","Voss","S. Smith","Pambuccian","Shang","Wietgrefe","Southern","Reilly","Skinner","Zupancic","Carlis","Piatak","Waterman","Keith Reeves","Masek-Hammerman","Derdeyn","Alpert","Evans","Kohler","Mller","Robinson","Lifson","Burton","Johnson","Haase"],"categories":null,"content":"","date":1406851200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1406851200,"objectID":"8893e040c717513d161f0ef4559c7dca","permalink":"/publication/25135832/","publishdate":"2014-08-01T00:00:00Z","relpermalink":"/publication/25135832/","section":"publication","summary":"We sought design principles for a vaccine to prevent HIV transmission to women by identifying correlates of protection conferred by a highly effective live attenuated SIV vaccine in the rhesus macaque animal model. We show that SIVmac239nef vaccination recruits plasma cells and induces ectopic lymphoid follicle formation beneath the mucosal epithelium in the rhesus macaque female reproductive tract. The plasma cells and ectopic follicles produce IgG Abs reactive with viral envelope glycoprotein gp41 trimers, and these Abs are concentrated on the path of virus entry by the neonatal FcR in cervical reserve epithelium and in vaginal epithelium. This local Ab production and delivery system correlated spatially and temporally with the maturation of local protection against high-dose pathogenic SIV vaginal challenge. Thus, designing vaccines to elicit production and concentration of Abs at mucosal frontlines could aid in the development of an effective vaccine to protect women against HIV-1.\n","tags":null,"title":"Live simian immunodeficiency virus vaccine correlate of protection: local antibody production and concentration on the path of virus entry.\n","type":"publication"},{"authors":["Shang","S. Smith","Duan","Perkey","Qu","Wietgrefe","Zupancic","Southern","Masek-Hammerman","Keith Reeves","Johnson","Haase"],"categories":null,"content":"","date":1401580800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1401580800,"objectID":"f59a3ea9eaad147b05b5bdbc0ab34efd","permalink":"/publication/24899503/","publishdate":"2014-06-01T00:00:00Z","relpermalink":"/publication/24899503/","section":"publication","summary":"NK cell responses to HIV/SIV infection have been well studied in acute and chronic infected patients/monkeys, but little is known about NK cells during viral transmission, particularly in mucosal tissues. In this article, we report a systematic study of NK cell responses to high-dose vaginal exposure to SIVmac251 in the rhesus macaque female reproductive tract (FRT). Small numbers of NK cells were recruited into the FRT mucosa following vaginal inoculation. The influx of mucosal NK cells preceded local virus replication and peaked at 1 wk and, thus, was in an appropriate time frame to control an expanding population of infected cells at the portal of entry. However, NK cells were greatly outnumbered by recruited target cells that fuel local virus expansion and were spatially dissociated from SIV RNA+ cells at the major site of expansion of infected founder populations in the transition zone and adjoining endocervix. The number of NK cells in the FRT mucosa decreased rapidly in the second week, while the number of SIV RNA+ cells in the FRT reached its peak. Mucosal NK cells produced IFN- and MIP-1/CCL3 but lacked several markers of activation and cytotoxicity, and this was correlated with inoculum-induced upregulation of the inhibitory ligand HLA-E and downregulation of the activating receptor CD122/IL-2R. Examination of SIVnef-vaccinated monkeys suggested that recruitment of NK cells to the genital mucosa was not involved in vaccine-induced protection from vaginal challenge. In summary, our results suggest that NK cells play, at most, a limited role in defenses in the FRT against vaginal challenge.\n","tags":null,"title":"NK cell responses to simian immunodeficiency virus vaginal exposure in naive and vaccinated rhesus macaques.\n","type":"publication"},{"authors":["Stephanie Jost","Tomezsko","Rands","Toth","Lichterfeld","Gandhi","Altfeld"],"categories":null,"content":"","date":1398902400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1398902400,"objectID":"c4ab7924590d3c07dedae2e7d26db2a0","permalink":"/publication/24829350/","publishdate":"2014-05-01T00:00:00Z","relpermalink":"/publication/24829350/","section":"publication","summary":"UNLABELLED: Increasing data suggest that NK cells can mediate antiviral activity in HIV-1-infected humans, and as such, novel approaches harnessing the anti-HIV-1 function of both T cells and NK cells represent attractive options to improve future HIV-1 immunotherapies. Chronic progressive HIV-1 infection has been associated with a loss of CD4(+) T helper cell function and with the accumulation of anergic NK cells. As several studies have suggested that cytokines produced by CD4(+) T cells are required to enhance NK cell function in various infection models, we hypothesized that reconstitution of HIV-1-specific CD4(+) T-cell responses by therapeutic immunization would restore NK cell activity in infected individuals. Using flow cytometry, we examined the function of CD4(+) T cells and NK cells in response to HIV-1 in subjects with treated chronic HIV-1 infection before and after immunization with an adjuvanted HIV-1 Gp120/NefTat subunit protein vaccine candidate provided by GlaxoSmithKline. Vaccination induced an increased expression of interleukin-2 (IL-2) by Gp120-specific CD4(+) T cells in response to HIV-1 peptides ex vivo, which was associated with enhanced production of gamma interferon (IFN-) by NK cells. Our data show that reconstitution of HIV-1-specific CD4(+) T-cell function by therapeutic immunization can enhance NK cell activity in HIV-1-infected individuals.\n      IMPORTANCE: NK cells are effector cells of the innate immune system and are important in the control of viral infection. Recent studies have demonstrated the crucial role played by NK cells in controlling and/or limiting acquisition of HIV-1 infection. However, NK cell function is impaired during progressive HIV-1 infection. We recently showed that therapeutic immunization of treated HIV-1-infected individuals reconstituted strong T-cell responses, measured notably by their production of IL-2, a cytokine that can activate NK cells. The current study suggests that reconstitution of T-cell function by therapeutic vaccination can enhance NK cell activity in individuals with chronic HIV-1 infection. Our findings provide new insights into the interplay between adaptive and innate immune mechanisms involved in HIV-1 immunity and unveil opportunities to harness NK cell function in future therapeutic vaccine strategies to target HIV-1.\n","tags":null,"title":"CD4+ T-cell help enhances NK cell function following therapeutic HIV-1 vaccination.\n","type":"publication"},{"authors":["Sasikala-Appukuttan","Kim","Kinzel","Hong","S. Smith","Wagstaff","Reilly","Piatak","Lifson","Keith Reeves","Johnson","Haase","Skinner"],"categories":null,"content":"","date":1385856000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1385856000,"objectID":"c2e9ee0cd3aebf07e94c2b4815fcc686","permalink":"/publication/24349100/","publishdate":"2013-12-01T00:00:00Z","relpermalink":"/publication/24349100/","section":"publication","summary":"Live-attenuated SIV vaccines (LAVs) have been the most effective to date in preventing or partially controlling infection by wild-type SIV in non-human primate models of HIV-1 transmission to women acting by mechanisms of protection that are not well understood. To gain insights into mechanisms of protection by LAVs that could aid development of effective vaccines to prevent HIV-1 transmission to women, we used in situ tetramer staining to determine whether increased densities or changes in the local distribution of SIV-specific CD8 T cells correlated with the maturation of SIVnef vaccine-induced protection prior to and after intra-vaginal challenge with wild-type SIVmac251. We evaluated the immunodominant Mamu-A1*001:01/Gag (CM9) and Mamu-A1*001:01/Tat (SL8) epitope response in genital and lymphoid tissues, and found that tetramer+ cells were present at all time points examined. In the cervical vaginal tissues, most tetramer+ cells were distributed diffusely throughout the lamina propria or co-localized with other CD8 T cells within lymphoid aggregates. The distribution and densities of the tetramer+ cells at the portal of entry did not correlate with the maturation of protection or change after challenge. Given these findings, we discuss the possibility that changes in other aspects of the immune system, including the quality of the resident population of virus-specific effector CD8 T cells could contribute to maturation of protection, as well as the potential for vaccine strategies that further increase the size and quality of this effector population to prevent HIV-1 transmission.\n","tags":null,"title":"Location and dynamics of the immunodominant CD8 T cell response to SIVnef immunization and SIVmac251 vaginal challenge.\n","type":"publication"},{"authors":["Carville","Evans","Keith Reeves"],"categories":null,"content":"","date":1383264000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1383264000,"objectID":"f56ed694f35dff6f6a2b6b1c3b313063","permalink":"/publication/24244365/","publishdate":"2013-11-01T00:00:00Z","relpermalink":"/publication/24244365/","section":"publication","summary":"Despite extensive use of nonhuman primates as models for infectious diseases and reproductive biology, imprecise phenotypic and functional definitions exist for natural killer (NK) cells. This deficit is particularly significant in the burgeoning use of small, less expensive New World primate species. Using polychromatic flow cytometry, we identified peripheral blood NK cells as CD3-negative and expressing a cluster of cell surface molecules characteristic of NK cells (i.e., NKG2A, NKp46, NKp30) in three New World primate species - common marmosets, cotton-top tamarins, and squirrel monkeys. We then assessed subset distribution using the classical NK markers, CD56 and CD16. In all species, similar to Old World primates, only a minor subset of NK cells was CD56+, and the dominant subset was CD56-CD16+. Interestingly, CD56+ NK cells were primarily cytokine-secreting cells, whereas CD56-CD16+ NK cells expressed significantly greater levels of intracellular perforin, suggesting these cells might have greater potential for cytotoxicity. New World primate species, like Old World primates, also had a minor CD56-CD16- NK cell subset that has no obvious counterpart in humans. Herein we present phenotypic profiles of New World primate NK cell subpopulations that are generally analogous to those found in humans. This conservation among species should support the further use of these species for biomedical research.\n","tags":null,"title":"Characterization of circulating natural killer cells in neotropical primates.\n","type":"publication"},{"authors":["Song","Josleyn","Janosko","Skinner","Keith Reeves","Cohen","Jett","Johnson","Blaney","Bollinger","Jennings","Jahrling"],"categories":null,"content":"","date":1380585600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1380585600,"objectID":"a52042c49c46c284a8da4707f09e653d","permalink":"/publication/24147080/","publishdate":"2013-10-01T00:00:00Z","relpermalink":"/publication/24147080/","section":"publication","summary":"Natural killer (NK) cells play critical roles in innate immunity and in bridging innate and adaptive immune responses against viral infection. However, the response of NK cells to monkeypox virus (MPXV) infection is not well characterized. In this intravenous challenge study of MPXV infection in rhesus macaques (Macaca mulatta), we analyzed blood and lymph node NK cell changes in absolute cell numbers, cell proliferation, chemokine receptor expression, and cellular functions. Our results showed that the absolute number of total NK cells in the blood increased in response to MPXV infection at a magnitude of 23-fold, manifested by increases in CD56+, CD16+, CD16-CD56- double negative, and CD16+CD56+ double positive NK cell subsets. Similarly, the frequency and NK cell numbers in the lymph nodes also largely increased with the total NK cell number increasing 46.1-fold. NK cells both in the blood and lymph nodes massively proliferated in response to MPXV infection as measured by Ki67 expression. Chemokine receptor analysis revealed reduced expression of CXCR3, CCR7, and CCR6 on NK cells at early time points (days 2 and 4 after virus inoculation), followed by an increased expression of CXCR3 and CCR5 at later time points (days 7-8) of infection. In addition, MPXV infection impaired NK cell degranulation and ablated secretion of interferon- and tumor necrosis factor-. Our data suggest a dynamic model by which NK cells respond to MPXV infection of rhesus macaques. Upon virus infection, NK cells proliferated robustly, resulting in massive increases in NK cell numbers. However, the migrating capacity of NK cells to tissues at early time points might be reduced, and the functions of cytotoxicity and cytokine secretion were largely compromised. Collectively, the data may explain, at least partially, the pathogenesis of MPXV infection in rhesus macaques.\n","tags":null,"title":"Monkeypox virus infection of rhesus macaques induces massive expansion of natural killer cells but suppresses natural killer cell functions.\n","type":"publication"},{"authors":["Li","Gillis","Johnson","Keith Reeves"],"categories":null,"content":"","date":1380585600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1380585600,"objectID":"c2c59b3e240ad5985a1f440f72369809","permalink":"/publication/23746074/","publishdate":"2013-10-01T00:00:00Z","relpermalink":"/publication/23746074/","section":"publication","summary":"The objective of this study was to determine the systemic effects of chronic simian immunodeficiency virus (SIV) infection on plasmacytoid dendritic cells (pDCs). pDCs play a critical role in antiviral immunity, but current data are conflicting on whether pDCs inhibit HIV/SIV replication, or, alternatively, contribute to chronic immune activation and disease. Furthermore, previous pDC studies have been complicated by incomplete descriptions of generalized depletion during HIV/SIV infection, and the effects of infection on pDCs outside peripheral blood remain unclear. In scheduled-sacrifice studies of naive and chronically SIV-infected rhesus macaques we evaluated the distribution and functionality of pDCs in multiple tissues using surface and intracellular polychromatic flow cytometry. As previously observed, pDCs were reduced in peripheral blood and spleens, but were also depleted in non-lymphoid organs such as the liver. Interestingly, pDCs accumulated up to fourfold in jejunum, colon and gut-draining lymph nodes, but not in peripheral lymph nodes. Most unexpectedly, SIV infection induced a multi-functional interferon-, tumour necrosis factor-, and macrophage inflammatory protein-1 cytokine secretion phenotype, whereas in normal animals these were generally distinct and separate functions. Herein we show a systemic redistribution of pDCs to gut tissues and gut-draining lymph nodes during chronic SIV infection, coupled to a novel multi-functional cytokine-producing phenotype. While pDC accumulation in the mucosa could aid in virus control, over-production of cytokines from these cells could also contribute to the increased immune activation in the gut mucosa commonly associated with progressive lentivirus infections.\n","tags":null,"title":"Multi-functional plasmacytoid dendritic cells redistribute to gut tissues during simian immunodeficiency virus infection.\n","type":"publication"},{"authors":["Evans","Keith Reeves"],"categories":null,"content":"","date":1375315200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1375315200,"objectID":"95dea8d58929cb88146a16294aade97b","permalink":"/publication/23966557/","publishdate":"2013-08-01T00:00:00Z","relpermalink":"/publication/23966557/","section":"publication","summary":"Tissue-directed trafficking of dendritic cells (DCs) as natural adjuvants and/or direct vaccine carriers is highly attractive for the next generation of vaccines and immunotherapeutics. Since these types of studies would undoubtedly be first conducted using nonhuman primate models, we evaluated the ability of all-trans-retinoic acid (ATRA) to induce gut-homing 47 expression on rhesus macaque plasmacytoid and myeloid DCs (pDCs and mDCs, respectively). Induction of 47 occurred in both a time-dependent and a dose-dependent manner with up to 8-fold increases for mDCs and 2-fold increases for pDCs compared to medium controls. ATRA treatment was also specific in inducing 47 expression, but not expression of another mucosal trafficking receptor, CCR9. Unexpectedly, upregulation of 47 was associated with a concomitant downregulation of CD62L, a marker of lymph node homing, indicating an overall shift in the trafficking repertoire. These same phenomena occurred with ATRA treatment of human and chimpanzee DCs, suggesting a conserved mechanism among primates. Collectively, these data serve as a first evaluation for ex vivo modification of primate DC homing patterns that could later be used in reinfusion studies for the purposes of immunotherapeutics or mucosa-directed vaccines.\n","tags":null,"title":"All-trans-retinoic acid imprints expression of the gut-homing marker 47 while suppressing lymph node homing of dendritic cells.\n","type":"publication"},{"authors":["Stephanie Jost","Moreno-Nieves","Garcia-Beltran","Rands","Reardon","Toth","Piechocka-Trocha","Altfeld","Addo"],"categories":null,"content":"","date":1372636800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1372636800,"objectID":"64ff7cabae68d0f3b06c2da66fa56773","permalink":"/publication/23866914/","publishdate":"2013-07-01T00:00:00Z","relpermalink":"/publication/23866914/","section":"publication","summary":"BACKGROUND: Natural killer (NK) cells constitutively express high levels of Tim-3, an immunoregulatory molecule recently proposed to be a marker for mature and functional NK cells. Whether HIV-1 infection modulates the expression of Tim-3 on NK cells, or the levels of its ligand Galectin-9 (Gal-9), and how signaling through these molecules affects the NK cell response to HIV-1 remains inadequately understood.\n      RESULTS: We analyzed Tim-3 and Gal-9 expression in a cohort of 85 individuals with early and chronic HIV-1 infection, and in 13 HIV-1 seronegative control subjects. HIV-1 infection was associated with reduced expression of Tim-3 on NK cells, which was normalized by HAART. Plasma concentrations of Gal-9 were higher in HIV-1-infected individuals than in healthy individuals. Interestingly, Gal-9 expression in immune cells was significantly elevated in early infection, with monocytes and dendritic cells displaying the highest expression levels, which correlated with HIV-1 viral loads. In vitro, Gal-9 triggered Tim-3 downregulation on NK cells as well as NK cell activation.\n      CONCLUSIONS: Our data suggest that high expression levels of Gal-9 during early HIV-1 infection can lead to enhanced NK cell activity, possibly allowing for improved early control of HIV-1. In contrast, persistent Gal-9 production might impair Tim-3 activity and contribute to NK cell dysfunction in chronic HIV-1 infection.\n","tags":null,"title":"Dysregulated Tim-3 expression on natural killer cells is associated with increased Galectin-9 levels in HIV-1 infection.\n","type":"publication"},{"authors":["Li","Evans","Keith Reeves"],"categories":null,"content":"","date":1372636800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1372636800,"objectID":"2ef208d6a707cc70d7b5c3417bae4ff4","permalink":"/publication/23898936/","publishdate":"2013-07-01T00:00:00Z","relpermalink":"/publication/23898936/","section":"publication","summary":"BACKGROUND: HIV and SIV infections induce NK cell dysfunction and hematopoietic defects in the bone marrow, but the effects of infection on bone marrow NK cell development and function are unknown.\n      METHODS: Bone marrow NK cells were analyzed from both nave and chronically SIV-infected rhesus macaques using polychromatic flow cytometry.\n      RESULTS: NK cell frequencies were reduced in infected compared with nave animals, associated with increased apoptosis. Bone marrow NK cells from SIV-infected macaques upregulated perforin expression, suggesting increased cytotoxicity, and shifted toward a more mature CD16(+) NK cell subpopulation phenotype. Unexpectedly, expression of the trafficking markers 47, CCR7, and CD62L was unchanged on bone marrow NK cells during SIV infection.\n      CONCLUSION: These data demonstrate that during SIV infection, bone marrow NK cells are reduced in number, but upregulate cytotoxic functions. Furthermore, our data suggest acquired cytotoxicity and loss may be due to in situ NK cell differentiation and not emigration.\n","tags":null,"title":"Loss of bone marrow NK cells during SIV infection is associated with increased turnover rates and cytotoxicity but not changes in trafficking.\n","type":"publication"},{"authors":["Hong","Rajakumar","Billingsley","Keith Reeves","Johnson"],"categories":null,"content":"","date":1359676800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1359676800,"objectID":"91d6c7ecda8199d910830a75fc0e79e6","permalink":"/publication/23423644/","publishdate":"2013-02-01T00:00:00Z","relpermalink":"/publication/23423644/","section":"publication","summary":"Human NK (hNK) cells play a key role in mediating host immune responses against various infectious diseases. For practical reasons, the majority of the data on hNK cells has been generated using peripheral blood lymphocytes. In contrast, our knowledge of NK cells in human tissues is limited, and not much is known about developmental pathways of hNK cell subpopulations in vivo. Although research in mice has elucidated a number of fundamental features of NK cell biology, mouse, and hNK cells significantly differ in their subpopulations, functions, and receptor repertoires. Thus, there is a need for a model that is more closely related to humans and yet allows experimental manipulations. Non-human primate models offer numerous opportunities for the study of NK cells, including the study of the role of NK cells after solid organ and stem cell transplantation, as well as in acute viral infection. Macaque NK cells can be depleted in vivo or adoptively transferred in an autologous system. All of these studies are either difficult or unethical to carry out in humans. Here we highlight recent advances in rhesus NK cell research and their parallels in humans. Using high-throughput transcriptional profiling, we demonstrate that the human CD56(bright) and CD56(dim) NK cell subsets have phenotypically and functionally analogous counterparts in rhesus macaques. Thus, the use of non-human primate models offers the potential to substantially advance hNK cell research.\n","tags":null,"title":"No monkey business: why studying NK cells in non-human primates pays off.\n","type":"publication"},{"authors":["Stephanie Jost","Altfeld"],"categories":null,"content":"","date":1356998400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1356998400,"objectID":"e15df87ed1cdf86b51e7a1f69d36fe00","permalink":"/publication/23298212/","publishdate":"2013-01-01T00:00:00Z","relpermalink":"/publication/23298212/","section":"publication","summary":"Natural killer (NK) cells are effector cells of the innate immune system and are important in the control of viral infections. Their relevance is reflected by the multiple mechanisms evolved by viruses to evade NK cell-mediated immune responses. Over recent years, our understanding of the interplay between NK cell immunity and viral pathogenesis has improved significantly. Here, we review the role of NK cells in the control of four important viral infections in humans: cytomegalovirus, influenza virus, HIV-1, and hepatitis C virus.\n","tags":null,"title":"Control of human viral infections by natural killer cells.\n","type":"publication"},{"authors":["Li","Keith Reeves"],"categories":null,"content":"","date":1356998400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1356998400,"objectID":"f2d65c9a781d1fa83d63003a8b1bf48d","permalink":"/publication/23316201/","publishdate":"2013-01-01T00:00:00Z","relpermalink":"/publication/23316201/","section":"publication","summary":"Despite the fact that the majority of human pathogens are transmitted across mucosal surfaces, including the oral mucosae, oral immunity is poorly understood. Furthermore, because the normal flora of the oral cavity is vast and significantly diverse, host immunity must balance a complex system of tolerance and pathogen recognition. Due to the rapid recognition and response to pathogens, the innate immune system, including natural killer (NK) cells, likely plays a critical role in mediating this balance. Because logistical and ethical restraints limit access to significant quantities of human mucosal tissues, non-human primate models offer one of the best opportunities to study mucosal NK cells. In this study we have identified both classical NK cells, as well as innate lymphoid cells (ILCs) in tonsillar and buccal tissues and oral-draining lymph nodes. Identified by mutually exclusive expression of NKG2A and NKp44, NK cells, and ILCs in the oral mucosa are generally phenotypically and functionally analogous to their gut counterparts. NKG2A(+) NK cells were more cytotoxic while NKp44(+) ILCs produced copious amounts of IL-17 and TNF-. However, in contrast to gut, oral NK cells and ILCs both produced large quantities of IFN- and the beta-chemokine, MIP-1. Also in contrast to what we have previously found in gut tissues of SIV-infected macaques, we found no reduction in NK cells during chronic SIV infection, but rather an expansion of ILCs in oral-draining lymph nodes and tonsils. These data suggest that the lentivirus-induced depletion of the NK cell/ILC compartment in the gut may be absent in the oral mucosa, but the inherent differences and SIV-induced alterations are likely to have significant impact on preventing oral opportunistic infections in lentiviral disease. Furthermore, these data extend our understanding of the oral innate immune system in general and could aid future studies evaluating the regulation of both normal oral flora and limiting transmission of oral mucosal pathogens.\n","tags":null,"title":"Functional perturbation of classical natural killer and innate lymphoid cells in the oral mucosa during SIV infection.\n","type":"publication"},{"authors":["Choi","Nguyen","Khavari","Keith Reeves","Snyder","Fletcher"],"categories":null,"content":"","date":1351728000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1351728000,"objectID":"f543c01aac6e8fbe2c204b40b9454cc2","permalink":"/publication/23143433/","publishdate":"2012-11-01T00:00:00Z","relpermalink":"/publication/23143433/","section":"publication","summary":"OBJECTIVES: The use of synthetic mesh for transvaginal pelvic organ prolapse (POP) repair is associated with the rare complication of mesh erosion into hollow viscera. This study presents a single-institution series of complex rectovaginal fistulas (RVFs) after synthetic mesh-augmented POP repair, as well as strategies for identification and management.\n      METHODS: Institutional review board approval was obtained for this retrospective study. Data were collected and analyzed on all female patients undergoing RVF repair from 2000 to 2011 at our institution.\n      RESULTS: Thirty-seven patients underwent RVF repair at our multidisciplinary center for restorative pelvic medicine. Of these, 10 (27.0%) were associated with POP repairs using mesh. The POP repairs resulting in RVF were transvaginal repair with mesh (n = 8), laparoscopic sacrocolpopexy with concomitant traditional posterior repair (n = 1), and robotic-assisted laparoscopic sacrocolpopexy (n = 1). Time to presentation was an average of 7.1 months after POP repair. Patients underwent a mean of 4.4 surgeries for definitive RVF repair, with 40% of patients requiring a bowel diversion (3 temporary ileostomies and 1 long-term colostomy). Mean follow-up time after last surgery was 9.2 months. On follow-up, 1 patient has a persistent fistula with vaginal mesh extrusion. One patient has persistent pelvic pain.\n      CONCLUSIONS: This series highlights the significant impact of synthetic mesh complications in the posterior compartment. These complications should be cautionary for synthetic graft use by those with limited experience, particularly when an alternate choice of traditional repair is available. When symptoms of RVF are present, collaboration with a colon and rectal specialist should be initiated as soon as possible for evaluation and definitive repair.\n","tags":null,"title":"Complex rectovaginal fistulas after pelvic organ prolapse repair with synthetic mesh:  a multidisciplinary approach to evaluation and management.\n","type":"publication"},{"authors":["Alpert","Harvey","Lauer","Keith Reeves","Piatak","Carville","Mansfield","Lifson","Li","Desrosiers","Johnson","Evans"],"categories":null,"content":"","date":1343779200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1343779200,"objectID":"e49685818a7c716adac3327132d4ced8","permalink":"/publication/22927823/","publishdate":"2012-08-01T00:00:00Z","relpermalink":"/publication/22927823/","section":"publication","summary":"Live-attenuated strains of simian immunodeficiency virus (SIV) routinely confer apparent sterilizing immunity against pathogenic SIV challenge in rhesus macaques. Understanding the mechanisms of protection by live-attenuated SIV may provide important insights into the immune responses needed for protection against HIV-1. Here we investigated the development of antibodies that are functional against neutralization-resistant SIV challenge strains, and tested the hypothesis that these antibodies are associated with protection. In the absence of detectable neutralizing antibodies, Env-specific antibody-dependent cell-mediated cytotoxicity (ADCC) emerged by three weeks after inoculation with SIVnef, increased progressively over time, and was proportional to SIVnef replication. Persistent infection with SIVnef elicited significantly higher ADCC titers than immunization with a non-persistent SIV strain that is limited to a single cycle of infection. ADCC titers were higher against viruses matched to the vaccine strain in Env, but were measurable against viruses expressing heterologous Env proteins. In two separate experiments, which took advantage of either the strain-specificity or the time-dependent maturation of immunity to overcome complete protection against SIV(mac)251 challenge, measures of ADCC activity were higher among the SIVnef-inoculated macaques that remained uninfected than among those that became infected. These observations show that features of the antibody response elicited by SIVnef are consistent with hallmarks of protection by live-attenuated SIV, and reveal an association between Env-specific antibodies that direct ADCC and apparent sterilizing protection by SIVnef.\n","tags":null,"title":"ADCC develops over time during persistent infection with live-attenuated SIV and is associated with complete protection against SIV(mac)251 challenge.\n","type":"publication"},{"authors":["Stephanie Jost","Altfeld","Chang"],"categories":null,"content":"","date":1341100800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1341100800,"objectID":"43eac2211fcd79d5e5a337b1c1bee01c","permalink":"/publication/22913253/","publishdate":"2012-07-01T00:00:00Z","relpermalink":"/publication/22913253/","section":"publication","summary":"The recent Keystone Symposia meeting on HIV Vaccines was held on 21-26 March 2012 in Keystone (CO, USA) back-to-back with the Viral Immunity meeting, creating synergy between the two areas of research. In this short report of the meeting, the authors will highlight three areas of interest that emerged from the two meetings: the recently emerging role of NK cells in modulating dendritic cell function, new data on the importance of dendritic cell antigen processing on priming of adaptive immunity and intriguing data suggesting that narrow targeting of very few protective epitopes restricted by a single MHC class I allele might be sufficient to mediate control of otherwise highly pathogenic SIV infection.\n","tags":null,"title":"Harnessing innate and adaptive immunity for viral vaccine design.\n","type":"publication"},{"authors":["Keith Reeves","Evans","Gillis","Wong","Kang","Li","Johnson"],"categories":null,"content":"","date":1338508800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1338508800,"objectID":"16be81322d1fbd05771db4eeddcd7959","permalink":"/publication/22711907/","publishdate":"2012-06-01T00:00:00Z","relpermalink":"/publication/22711907/","section":"publication","summary":"Multiple studies suggest that plasmacytoid dendritic cells (pDCs) are depleted and dysfunctional during human immunodeficiency virus/simian immunodeficiency virus (HIV/SIV) infection, but little is known about pDCs in the gut-the primary site of virus replication. Here, we show that during SIV infection, pDCs were reduced 3--fold in the circulation and significantly upregulated the gut-homing marker 47, but were increased 4-fold in rectal biopsies of infected compared to naive macaques. These data revise the understanding of pDC immunobiology during SIV infection, indicating that pDCs are not necessarily depleted, but instead may traffic to and accumulate in the gut mucosa.\n","tags":null,"title":"SIV infection induces accumulation of plasmacytoid dendritic cells in the gut mucosa.\n","type":"publication"},{"authors":["Stephanie Jost","Altfeld"],"categories":null,"content":"","date":1335830400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1335830400,"objectID":"dbaf4bc7d546a4ccc3016527d200eecd","permalink":"/publication/22626930/","publishdate":"2012-05-01T00:00:00Z","relpermalink":"/publication/22626930/","section":"publication","summary":"Human immunodeficiency virus type 1 (HIV-1) mostly owes its success to its ability to evade host immune responses. Understanding viral immune escape mechanisms is a prerequisite to improve future HIV-1 vaccine design. This review focuses on the strategies that HIV-1 has evolved to evade recognition by natural killer (NK) cells.\n","tags":null,"title":"Evasion from NK cell-mediated immune responses by HIV-1.\n","type":"publication"},{"authors":["Stephanie Jost","Quillay","Reardon","Peterson","Simmons","Parry","Bryant","Binder","Altfeld"],"categories":null,"content":"","date":1314835200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1314835200,"objectID":"26042a896993548b23fe32825f089830","permalink":"/publication/21966414/","publishdate":"2011-09-01T00:00:00Z","relpermalink":"/publication/21966414/","section":"publication","summary":"Several studies have highlighted the important role played by murine natural killer (NK) cells in the control of influenza infection. However, human NK cell responses in acute influenza infection, including infection with the 2009 pandemic H1N1 influenza virus, are poorly documented. Here, we examined changes in NK cell phenotype and function and plasma cytokine levels associated with influenza infection and vaccination. We show that absolute numbers of peripheral blood NK cells, and particularly those of CD56(bright) NK cells, decreased upon acute influenza infection while this NK cell subset expanded following intramuscular influenza vaccination. NK cells exposed to influenza antigens were activated, with higher proportions of NK cells expressing CD69 in study subjects infected with seasonal influenza strains. Vaccination led to increased levels of CD25+ NK cells, and notably CD56(bright) CD25+ NK cells, whereas decreased amounts of this subset were present in the peripheral blood of influenza infected individuals, and predominantly in study subjects infected with the 2009 pandemic H1N1 influenza virus. Finally, acute influenza infection was associated with low plasma concentrations of inflammatory cytokines, including IFN-, MIP-1, IL-2 and IL-15, and high levels of the anti-inflammatory cytokines IL-10 and IL-1ra. Altogether, these data suggest a role for the CD56(bright) NK cell subset in the response to influenza, potentially involving their recruitment to infected tissues and a local production and/or uptake of inflammatory cytokines.\n","tags":null,"title":"Changes in cytokine levels and NK cell activation associated with influenza.\n","type":"publication"},{"authors":["Keith Reeves","Rajakumar","Evans","Connole","Gillis","Wong","Kuzmichev","Carville","Johnson"],"categories":null,"content":"","date":1309478400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1309478400,"objectID":"131457aca986e252c091988ee3584bf4","permalink":"/publication/21791421/","publishdate":"2011-07-01T00:00:00Z","relpermalink":"/publication/21791421/","section":"publication","summary":"Natural killer (NK) cells are classically viewed as effector cells that kill virus-infected and neoplastic cells, but recent studies have identified a rare mucosal NK- cell subpopulation secreting the TH17 cytokine IL-22. Here, we report identification of 2 distinct lineages of mucosal NK cells characterized as NKG2A(+)NFIL3(+)RORC(-) and NKp44(+)NFIL3(+)RORC(+). NKG2A(+) NK cells were systemically distributed, cytotoxic, and secreted IFN-, whereas NKp44(+) NK cells were mucosae-restricted, noncytotoxic, and produced IL-22 and IL-17. During SIV infection, NKp44(+) NK cells became apoptotic, were depleted, and had an altered functional profile characterized by decreased IL-17 secretion; increased IFN- secretion; and, surprisingly, increased potential for cytotoxicity. NKp44(+) NK cells showed no evidence of direct SIV infection; rather, depletion and altered function were associated with SIV-induced up-regulation of inflammatory mediators in the gut, including indoleamine 2,3-dioxygenase 1. Furthermore, treatment of NKp44(+) NK cells with indoleamine 2,3-dioxygenase 1 catabolites in vitro ablated IL-17 production in a dose-dependent manner, whereas other NK-cell functions were unaffected. Thus lentiviral infection both depletes and modifies the functional repertoire of mucosal NK cells involved in the maintenance of gut integrity, a finding that highlights the plasticity of this rare mucosal NK-cell population.\n","tags":null,"title":"Gut inflammation and indoleamine deoxygenase inhibit IL-17 production and promote cytotoxic potential in NKp44+ mucosal NK cells during SIV infection.\n","type":"publication"},{"authors":["Moreland","Guethlein","Keith Reeves","Broman","Johnson","Parham","O'Connor","Bimber"],"categories":null,"content":"","date":1306886400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1306886400,"objectID":"3dd4906cf9b8d05f958be324d160e14c","permalink":"/publication/21645414/","publishdate":"2011-06-01T00:00:00Z","relpermalink":"/publication/21645414/","section":"publication","summary":"BACKGROUND: Human killer immunoglobulin-like receptors (KIRs) play a critical role in governing the immune response to neoplastic and infectious disease. Rhesus macaques serve as important animal models for many human diseases in which KIRs are implicated; however, the study of KIR activity in this model is hindered by incomplete characterization of KIR genetics.\n      RESULTS: Here we present a characterization of KIR genetics in rhesus macaques (Macaca mulatta). We conducted a survey of KIRs in this species, identifying 47 novel full-length KIR sequences. Using this expanded sequence library to build upon previous work, we present evidence supporting the existence of 22 Mamu-KIR genes, providing a framework within which to describe macaque KIRs. We also developed a novel pyrosequencing-based technique for KIR genotyping. This method provides both comprehensive KIR genotype and frequency estimates of transcript level, with implications for the study of KIRs in all species.\n      CONCLUSIONS: The results of this study significantly improve our understanding of macaque KIR genetic organization and diversity, with implications for the study of many human diseases that use macaques as a model. The ability to obtain comprehensive KIR genotypes is of basic importance for the study of KIRs, and can easily be adapted to other species. Together these findings both advance the field of macaque KIRs and facilitate future research into the role of KIRs in human disease.\n","tags":null,"title":"Characterization of killer immunoglobulin-like receptor genetics and comprehensive genotyping by pyrosequencing in rhesus macaques.\n","type":"publication"},{"authors":["Fofana","Colantonio","Keith Reeves","Connole","Gillis","Hall","Sato","Audin","Evans","Shida","Johnson","Johnson"],"categories":null,"content":"","date":1306886400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1306886400,"objectID":"0511088756a928e7b573982a10de9ad3","permalink":"/publication/21689659/","publishdate":"2011-06-01T00:00:00Z","relpermalink":"/publication/21689659/","section":"publication","summary":"SIV infection of macaques is the most widely employed model for preclinical AIDS vaccine and pathogenesis research. In macaques, high-titer virus-specific antibodies are induced by infection, and antibody responses can drive evolution of viral escape variants. However, neutralizing antibodies (Nabs) induced in response to SIVmac239 and SIVmac251 infection or immunization are generally undetectable or of low titer, and the identification and cloning of potent Nabs from SIVmac-infected macaques remains elusive. Based on recent advances in labeling HIV-specific B lymphocytes [1-3], we have generated recombinant, secreted, soluble SIVmac envelope (Env) proteins (gp120 and gp140) for detection and quantification of SIVmac Env-specific B lymphocytes. In contrast to HIV-1, we found that soluble SIVmac239 gp140 retains the ability to form stable oligomers without the necessity for introducing additional, stabilizing modifications. Soluble oligomeric gp140 reacted with rhesus anti-SIV Env-specific monoclonal antibodies (MAbs), and was used to deplete Env-specific antibodies with SIV neutralization capability from plasma taken from a rhesus macaque immunized with live attenuated SIVmac239nef. Soluble gp120 and gp140 bound to SIV-specific immortalized B cells, and to SIV Env-specific B lymphocytes in peripheral blood of immunized animals. These reagents will be useful for analyzing development of Env-specific B cell responses in preclinical studies using SIV-infected or vaccinated rhesus macaques.\n","tags":null,"title":"Flow cytometry based identification of simian immunodeficiency virus Env-specific B lymphocytes.\n","type":"publication"},{"authors":["Colantonio","Bimber","Neidermyer","Keith Reeves","Alter","Altfeld","Johnson","Carrington","O'Connor","Evans"],"categories":null,"content":"","date":1298937600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1298937600,"objectID":"a5e9ab940a0a3a9476bae2fd069cc620","permalink":"/publication/21423672/","publishdate":"2011-03-01T00:00:00Z","relpermalink":"/publication/21423672/","section":"publication","summary":"Molecular interactions between killer immunoglobulin-like receptors (KIRs) and their MHC class I ligands play a central role in the regulation of natural killer (NK) cell responses to viral pathogens and tumors. Here we identify Mamu-A1*00201 (Mamu-A*02), a common MHC class I molecule in the rhesus macaque with a canonical Bw6 motif, as a ligand for Mamu-KIR3DL05. Mamu-A1*00201 tetramers folded with certain SIV peptides, but not others, directly stained primary NK cells and Jurkat cells expressing multiple allotypes of Mamu-KIR3DL05. Differences in binding avidity were associated with polymorphisms in the D0 and D1 domains of Mamu-KIR3DL05, whereas differences in peptide-selectivity mapped to the D1 domain. The reciprocal exchange of the third predicted MHC class I-contact loop of the D1 domain switched the specificity of two Mamu-KIR3DL05 allotypes for different Mamu-A1*00201-peptide complexes. Consistent with the function of an inhibitory KIR, incubation of lymphocytes from Mamu-KIR3DL05(+) macaques with target cells expressing Mamu-A1*00201 suppressed the degranulation of tetramer-positive NK cells. These observations reveal a previously unappreciated role for D1 polymorphisms in determining the selectivity of KIRs for MHC class I-bound peptides, and identify the first functional KIR-MHC class I interaction in the rhesus macaque. The modulation of KIR-MHC class I interactions by viral peptides has important implications to pathogenesis, since it suggests that the immunodeficiency viruses, and potentially other types of viruses and tumors, may acquire changes in epitopes that increase the affinity of certain MHC class I ligands for inhibitory KIRs to prevent the activation of specific NK cell subsets.\n","tags":null,"title":"KIR polymorphisms modulate peptide-dependent binding to an MHC class I ligand with a Bw6 motif.\n","type":"publication"},{"authors":["Keith Reeves","Evans","Fultz","Johnson"],"categories":null,"content":"","date":1298937600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1298937600,"objectID":"3255a1c6496abd92e044c936858b4e0f","permalink":"/publication/21360701/","publishdate":"2011-03-01T00:00:00Z","relpermalink":"/publication/21360701/","section":"publication","summary":"Precise identification of NK-cell populations in humans and nonhuman primates has been confounded by imprecise phenotypic definitions. A common definition used in nonhuman primates, including chimpanzees, is CD3(-) CD8(+) CD16(+) , and this is the dominant NK-cell phenotype in peripheral blood. However, recent data suggest that in chimpanzees a rare CD8(-) CD16(+) population also exists. Herein, we present evidence validating the existence of this rare subset in chimpanzee peripheral blood, but also demonstrating that gating on CD3(-) CD8(-) CD16(+) cells can inadvertently include a large number of CD16(+) myeloid DCs (mDCs). We confirmed the inclusion of mDCs in CD3(-) CD8(-) CD16(+) gated cells by demonstrating high expression of CD11c, BDCA-1 and HLA-DR, and by the lack of expression of NKp46 and intracellular perforin. We also functionally validated the CD8(-) NK-cell and mDC populations by mutually exclusive responsiveness to a classical NK-cell stimulus, MHC class I-deficient cells, and a prototypic mDC stimulus, poly I:C, respectively. Overall, these data demonstrate common problems with gating of NK cells that can lead to erroneous conclusions and highlight a critical need for consensus protocols for NK-cell phenotyping.\n","tags":null,"title":"Potential confusion of contaminating CD16+ myeloid DCs with anergic CD16+ NK cells in chimpanzees.\n","type":"publication"},{"authors":["Keith Reeves","Evans","Gillis","Wong","Connole","Carville","Johnson"],"categories":null,"content":"","date":1296518400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1296518400,"objectID":"4472f3596a8f34b558436832056d2fa1","permalink":"/publication/21315723/","publishdate":"2011-02-01T00:00:00Z","relpermalink":"/publication/21315723/","section":"publication","summary":"Since the vast majority of infections occur at mucosal surfaces, accurate characterization of mucosal immune cells is critically important for understanding transmission and control of infectious diseases. Standard flow cytometric analysis of cells obtained from mucosal tissues can provide valuable information on the phenotype of mucosal leukocytes and their relative abundance, but does not provide absolute cell counts of mucosal cell populations. We developed a bead-based flow cytometry assay to determine the absolute numbers of multiple mononuclear cell types in colorectal biopsies of rhesus macaques. Using 10-color flow cytometry panels and pan-fluorescent beads, cells were enumerated in biopsy specimens by adding a constant ratio of beads per mg of tissue and then calculating cell numbers/mg of tissue based on cell-to-bead ratios determined at the time of sample acquisition. Testing in duplicate specimens showed the assay to be highly reproducible (Spearman R=0.9476, P","tags":null,"title":"Quantification of mucosal mononuclear cells in tissues with a fluorescent bead-based polychromatic flow cytometry assay.\n","type":"publication"},{"authors":["Stephanie Jost","Reardon","Peterson","Poole","Bosch","Alter","Altfeld"],"categories":null,"content":"","date":1293840000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1293840000,"objectID":"0b32bf4caed0646d942934f442a94f3a","permalink":"/publication/21214542/","publishdate":"2011-01-01T00:00:00Z","relpermalink":"/publication/21214542/","section":"publication","summary":"Several studies have highlighted the importance of murine natural killer (NK) cells in the control of influenza virus infection, notably through the natural cytotoxicity receptor NKp46. However, little is known about the involvement of NK cells in human influenza infection. Here, we show that upon in vitro exposure to influenza, NKp46 expression on NK cells decreases, whereas expression of 2B4, an activating receptor that can enhance natural cytotoxicity in synergy with NKp46, is up-regulated. Consistent with these observations, NKp46(dull) and 2B4(bright) NK cells had a higher functional activity in response to influenza than NK cells expressing high levels of NKp46 or low levels of 2B4, respectively. Importantly, we assessed whether the expression of these receptors was also modified in vivo in response to influenza antigens and showed that an increase in 2B4-expressing NK cells and a decrease in NKp46(+) NK cells occurred following intramuscular influenza vaccination. Altogether, our results further suggest that NKp46 may play an important role in the innate immune response to human influenza and reveal that exposure to influenza antigens is associated with a previously unrecognized increase in 2B4 expression that can impact NK cell activity against the virus.\n","tags":null,"title":"Expansion of 2B4+ natural killer (NK) cells and decrease in NKp46+ NK cells in response to influenza.\n","type":"publication"},{"authors":["Ackerman","Moldt","Wyatt","Dugast","McAndrew","Tsoukas","Stephanie Jost","Berger","Sciaranghella","Liu","Irvine","Burton","Alter"],"categories":null,"content":"","date":1291161600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1291161600,"objectID":"2183c79927edf8efca1974a4cd8f9d7e","permalink":"/publication/21192942/","publishdate":"2010-12-01T00:00:00Z","relpermalink":"/publication/21192942/","section":"publication","summary":"Phagocytosis can be induced via the engagement of Fc receptors by antibody-opsonized material. Furthermore, the efficiency of antibody-induced effector functions has been shown to be dramatically modulated by changes in antibody glycosylation. Because infection can modulate antibody glycans, which in turn modulate antibody functions, assays capable of determining the induction of effector functions rather than neutralization or titer provide a valuable opportunity to more fully characterize the quality of the adaptive immune response. Here we describe a robust and high-throughput flow cytometric assay to define the phagocytic activity of antigen-specific antibodies from clinical samples. This assay employs a monocytic cell line that expresses numerous Fc receptors: including inhibitory and activating, and high and low affinity receptors--allowing complex phenotypes to be studied. We demonstrate the adaptability of this high-throughput, flow-based assay to measure antigen-specific antibody-mediated phagocytosis against an array of viruses, including influenza, HIV, and dengue. The phagocytosis assay format further allows for simultaneous analysis of cytokine release, as well as determination of the role of specific Fc-receptor subtypes, making it a highly useful system for parsing differences in the ability of clinical and vaccine induced antibody samples to recruit this critical effector function.\n","tags":null,"title":"A robust, high-throughput assay to determine the phagocytic activity of clinical antibody samples.\n","type":"publication"},{"authors":["Alter","Stephanie Jost","Rihn","Reyor","Nolan","Ghebremichael","Bosch","Altfeld","Lauer"],"categories":null,"content":"","date":1291161600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1291161600,"objectID":"441564977a781367172a0676da7fe020","permalink":"/publication/21168454/","publishdate":"2010-12-01T00:00:00Z","relpermalink":"/publication/21168454/","section":"publication","summary":"BACKGROUND \u0026 AIMS: While the majority of HCV-infected patients progress to chronic hepatitis, a small fraction of individuals are able to clear the virus. Resolution of infection occurs within the first few weeks to months of infection, suggesting that innate immune functions may be critical for early control. Epidemiologic data support a role for particular NK cell receptor bearing populations in this control, yet the mechanism by which NK cells respond to HCV early in infection is unknown.\n      METHODS: Changes in the phenotype and function of NK cells were investigated in a cohort of 43 individuals identified during various stages of HCV infection with different clinical outcomes.\n      RESULTS: Acute, chronic, and resolved HCV infections were characterized by an expansion of CD56(neg) NK cells. Furthermore, increased levels of HLA-C-binding KIR(+) NK cells were observed in HCV resolvers, while all stages of HCV infection were associated with reduced percentages of NKG2D(+), NKp30(+), and NKp46(+) NK cells, and a slight increase in the ability of NK cells to respond to target cells bearing the ligands for these receptors. In contrast, NKG2A(+) and CD94(+) NK cells were elevated in acute and chronic HCV infection, but not in resolved infection. Most importantly, in acute infection, lower frequencies of NKp30(+), NKp46(+), CD161(+), and NKG2D(+) NK cells were observed in patients who were subsequently able to clear HCV infection than in those becoming chronically infected.\n      CONCLUSIONS: These data implicate particular populations of NK cells in the early control and clearance of HCV infection.\n","tags":null,"title":"Reduced frequencies of NKp30+NKp46+, CD161+, and NKG2D+ NK cells in acute HCV infection may predict viral clearance.\n","type":"publication"},{"authors":["Nolting","Dugast","Rihn","Luteijn","Carrington","Kane","Stephanie Jost","Toth","Nagami","Faetkenheuer","Hartmann","Altfeld","Alter"],"categories":null,"content":"","date":1277942400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1277942400,"objectID":"3bd055373f886469df336397b59c763e","permalink":"/publication/20667578/","publishdate":"2010-07-01T00:00:00Z","relpermalink":"/publication/20667578/","section":"publication","summary":"Natural killer (NK) cells play a critical role in host defense against viral infections. However chronic HIV-1 infection is associated with an accumulation of dysfunctional NK cells, that poorly control viral replication. The underlying mechanisms for this NK cell mediated dysfunction are not understood. Certain tumors evade NK cell mediated detection by dampening NK cell activity through the downregulation of NKG2D, via the release of soluble NKG2D-ligands, resulting in a potent suppression of NK cell function. Here we show that chronic HIV-1 infection is associated with a specific defect in NKG2D-mediated NK cell activation, due to reduced expression and transcription of NKG2D. Reduced NKG2D expression was associated with elevated levels of the soluble form of the NKG2D-ligand, MICA, in patient sera, likely released by HIV+CD4+ T cells. Thus, like tumors, HIV-1 may indirectly suppress NK cell recognition of HIV-1-infected CD4+ T cells by enhancing NKG2D-ligand secretion into the serum resulting in a profound impairment of NK cell function.\n","tags":null,"title":"MHC class I chain-related protein A shedding in chronic HIV-1 infection is associated with profound NK cell dysfunction.\n","type":"publication"},{"authors":["Keith Reeves","Wei","Fultz"],"categories":null,"content":"","date":1275350400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1275350400,"objectID":"c73fea60e2e23d1b2487635e788681d3","permalink":"/publication/20554805/","publishdate":"2010-06-01T00:00:00Z","relpermalink":"/publication/20554805/","section":"publication","summary":"Fms-like tyrosine kinase 3 ligand (FLT3-L) is critical for the differentiation and self-renewal of CD34+ progenitor cells in primates and has been used therapeutically to mobilize progenitor and dendritic cells in vivo. However, little is known regarding the expansion of progenitor cells outside of peripheral blood, particularly in bone marrow (BM), where progenitor cells primarily reside. Evaluation of FLT3-L-mediated cell mobilization during lentivirus infections, where the numbers of CD34+ progenitor cells are reduced, is limited. We enumerated frequencies and absolute numbers of CD34+ progenitor cells in blood and BM of naive and SIV- or SHIV-infected macaques during and after the administration of FLT3-L. Flow cytometric analyses revealed that, while CD34+ cells increased in the circulation, no expansion was observed in BM. Furthermore, in the BM intracellular Ki67, a marker of cell proliferation, was downregulated in CD34+ progenitor cells but was upregulated significantly in the bulk cell population. Although the exact mechanism(s) remains unclear, these data suggest that CD34+ cell mobilization in blood was the result of cellular emigration from BM and not the proliferation of CD34+ cells already in the periphery. It is possible that the decreased progenitor cell proliferation observed in BM is evidence of a negative regulatory mechanism preventing hyperproliferation and development of neoplastic cells.\n","tags":null,"title":"Mobilization of CD34+ progenitor cells in association with decreased proliferation in the bone marrow of macaques after administration of the Fms-like tyrosine kinase 3 ligand.\n","type":"publication"},{"authors":["Keith Reeves","Evans","Gillis","Johnson"],"categories":null,"content":"","date":1275350400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1275350400,"objectID":"2a10286be2e4b3b74af40eca4c20e944","permalink":"/publication/20554780/","publishdate":"2010-06-01T00:00:00Z","relpermalink":"/publication/20554780/","section":"publication","summary":"Herein we demonstrate that chronic simian immunodeficiency virus (SIV) infection induces significant upregulation of the gut-homing marker alpha4beta7 on macaque NK cells, coupled with downregulation of the lymph node-trafficking marker, CCR7. Interestingly, in nave animals, alpha4beta7 expression was associated with increased NK cell activation and, on CD16(+) NK cells, delineated a unique dual-function cytotoxic-CD107a(+)/gamma interferon (IFN-gamma)-secreting population. However, while SIV infection increased CD107a expression on stimulated CD56(+) NK cells, alpha4beta7(+) and alpha4beta7(-) NK cells were affected similarly. These findings suggest that SIV infection redirects NK cells away from the lymph nodes to the gut mucosae but alters NK cell function independent of trafficking repertoires.\n","tags":null,"title":"Simian immunodeficiency virus infection induces expansion of alpha4beta7+ and cytotoxic CD56+ NK cells.\n","type":"publication"},{"authors":["Keith Reeves","Gillis","Wong","Yu","Connole","Johnson"],"categories":null,"content":"","date":1267401600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1267401600,"objectID":"2b8df52f7f9e5a3821dd9b43a68bd333","permalink":"/publication/20339088/","publishdate":"2010-03-01T00:00:00Z","relpermalink":"/publication/20339088/","section":"publication","summary":"Natural killer (NK) cells contribute to control of HIV/SIV infection. We defined macaque NK-cell subsets based on expression of CD56 and CD16 and found their distribution to be highly disparate. CD16(+) NK cells predominated in peripheral blood, whereas most mucosal NK cells were CD56(+), and lymph nodes contained both CD56(+) and CD16(-)CD56(-) (double-negative [DN]) subsets. Functional profiles were also distinct among subsets--CD16(+) NK cells expressed high levels of cytolytic molecules, and CD56(+) NK cells were predominantly cytokine-secreting cells, whereas DN NK possessed both functions. In macaques chronically infected with SIV, circulating CD16(+) and DN NK cells were expanded in number and, although markers of cytoxicity increased, cytokine secretion decreased. Notably, CD56(+) NK cells in SIV-infected animals up-regulated perforin, granzyme B, and CD107a. In contrast, the lymph node-homing molecules CD62 ligand (CD62L) and C-C chemokine receptor type 7 (CCR7), which are expressed primarily on CD56(+) and DN NK cells, were significantly down-regulated on NK cells from infected animals. These data demonstrate that SIV infection drives a shift in NK-cell function characterized by decreased cytokine production, expanded cytotoxicity, and trafficking away from secondary lymphoid organs, suggesting that the NK-cell repertoire is not only heterogeneous but also plastic.\n","tags":null,"title":"CD16- natural killer cells: enrichment in mucosal and secondary lymphoid tissues and altered function during chronic SIV infection.\n","type":"publication"},{"authors":["Keith Reeves","Wei","Stallworth","Fultz"],"categories":null,"content":"","date":1259625600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1259625600,"objectID":"6e992146da4c4dfcfc59f8072a6e4dc8","permalink":"/publication/20001520/","publishdate":"2009-12-01T00:00:00Z","relpermalink":"/publication/20001520/","section":"publication","summary":"Reports indicate that myeloid and plasmacytoid dendritic cells (mDCs and pDCs), which are key effector cells in host innate immune responses, can be infected with HIV-1 and are reduced in number and function during the chronic phase of HIV disease. Furthermore, it was recently demonstrated that a sustained loss of mDCs and pDCs occurs in SIV-infected macaques. Since loss of functional DC populations might impair innate immune responses to opportunistic microorganisms and neoplastic cells, we explored whether inoculation of naive and SIV- or SHIV-infected pigtailed macaques with the hematopoietic cytokine FLT3-ligand (FLT3-L) would expand the number of mDCs and pDCs in vivo. After the macaques received supraphysiologic doses of FLT3-L, mDCs, pDCs, and monocytes increased up to 45-fold in blood, lymph nodes, and bone marrow (BM), with DC expansion in the BM preceding mobilization in blood and lymphoid tissues. FLT3-L also increased serum levels of IL-12, at least transiently, and elicited higher surface expression of HLA-DR and the activation markers CD25 and CD69 on NK and T cells. During and after treatment of infected animals, APCs increased in number and were activated; however, CD4(+) T cell numbers, virion RNA, and anti-SIV/SHIV antibody titers remained relatively stable, suggesting that FLT3-L might be a safe modality to expand DC populations and provide therapeutic benefit during chronic lentivirus infections.\n","tags":null,"title":"Systemic dendritic cell mobilization associated with administration of FLT3 ligand to SIV- and SHIV-infected macaques.\n","type":"publication"},{"authors":["Salisch","Kaufmann","Awad","Keith Reeves","Tighe","Li","Piatak","Lifson","Evans","Pereyra","Freeman","Johnson"],"categories":null,"content":"","date":1257033600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1257033600,"objectID":"56fe25d5942545b53eebb5499a09d283","permalink":"/publication/19949078/","publishdate":"2009-11-01T00:00:00Z","relpermalink":"/publication/19949078/","section":"publication","summary":"Ongoing antigenic stimulation appears to be an important prerequisite for the persistent expression of programmed death 1 (PD-1), an inhibitory TCR coreceptor of the CD28 family. Although recent publications have emphasized the utility of PD-1 as a marker for dysfunctional T cells in chronic viral infections, its dependence on antigenic stimulation potentially renders it a sensitive indicator of low-level viral replication. To explore the antigenic threshold for the maintenance of PD-1 expression on virus-specific T cells, we compared PD-1 expression on virus-specific and memory T cell populations in controlled and uncontrolled SIV and HIV-1 infection. In both controlled live attenuated SIV infection in rhesus macaques and HIV-1 infection in elite controllers, elevated levels of PD-1 expression were observed on SIV- and HIV-1-specific CD8(+) T cells. However, in contrast to chronic wild-type SIV infection and uncontrolled HIV-1 infection, controlled SIV/HIV-1 infection did not result in increased expression of PD-1 on total memory T cells. PD-1 expression on SIV-specific CD8(+) T cells rapidly decreased after the emergence of CTL escape in cognate epitopes, but was maintained in the setting of low or undetectable levels of plasma viremia in live attenuated SIV-infected macaques. After inoculation of naive macaques with a single-cycle SIV, PD-1 expression on SIV-specific CD8(+) T cells initially increased, but was rapidly downregulated. These results demonstrate that PD-1 can serve as a sensitive indicator of persistent, low-level virus replication and that generalized PD-1 expression on T lymphocytes is a distinguishing characteristic of uncontrolled lentiviral infections.\n","tags":null,"title":"Inhibitory TCR coreceptor PD-1 is a sensitive indicator of low-level replication of SIV and HIV-1.\n","type":"publication"},{"authors":["Liu","Sun","Rihn","Nolting","Tsoukas","Stephanie Jost","Cohen","Walker","Alter"],"categories":null,"content":"","date":1243814400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1243814400,"objectID":"e0eab764db9473d2768c52477b05f9dc","permalink":"/publication/19553339/","publishdate":"2009-06-01T00:00:00Z","relpermalink":"/publication/19553339/","section":"publication","summary":"Increasing evidence suggests that NK cells not only are critical in the initial host defense against pathogens but also may contribute to continued protection from human immunodeficiency virus type 1 (HIV-1) disease progression. NK cell cytolysis can be induced directly through diverse receptor families or can be induced indirectly through Fc receptors by antibodies mediating antibody-dependent cellular cytotoxicity (ADCC). ADCC has been implicated in both protection from simian immunodeficiency virus infection and slower progression of HIV-1 disease. ADCC activity declines with advancing infection, and yet the underlying mechanism for this dysfunction has not been defined, nor has it been determined whether the activity can be reconstituted. Here we demonstrate that NK cell-mediated ADCC is severely compromised in chronic HIV infection. The potency of ADCC function was directly correlated with baseline Fc gammaRIIIa receptor (CD16) expression on NK cells. CD16 expression was negatively influenced by elevated expression of a group of enzymes, the matrix metalloproteinases (MMPs), normally involved in tissue/receptor remodeling. Inhibition of MMPs resulted in increased CD16 expression and augmented ADCC activity in response to antibody-coated target cells. These data suggest that MMP inhibitors may improve NK cell-mediated ADCC, which may provide subjects with an opportunity to harness the cytolytic power of NK cells through naturally occurring nonneutralizing HIV-specific antibodies.\n","tags":null,"title":"Matrix metalloprotease inhibitors restore impaired NK cell-mediated antibody-dependent cellular cytotoxicity in human immunodeficiency virus type 1 infection.\n","type":"publication"},{"authors":["Turelli","Liagre-Quazzola","Mangeat","Verp","Stephanie Jost","Trono"],"categories":null,"content":"","date":1207008000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1207008000,"objectID":"860a0d1ee57e9775a9141c38676349eb","permalink":"/publication/18434399/","publishdate":"2008-04-01T00:00:00Z","relpermalink":"/publication/18434399/","section":"publication","summary":"Interferon (IFN) has been part of the standard treatment of chronic hepatitis B infection for more than 2 decades, yet the mechanism of action of this antiviral remains poorly understood. It was recently observed that members of the human APOBEC family of cytidine deaminases endowed with anti-hepatitis B virus (HBV) activity are upregulated by type I and II IFNs. However, we demonstrated that, in tissue culture, these cellular enzymes are not essential effectors of the anti-HBV action of these cytokines. Here, we show that murine APOBEC3 (muA3) can also block HBV replication. While expressed at low levels in the mouse liver at baseline, muA3 is upregulated upon IFN induction. However, in HBV-transgenic muA3 knockout mice, IFN induction blocked HBV DNA production as efficiently as in control HBV-transgenic muA3-competent animals. We conclude that APOBEC3 is not an essential mediator of the IFN-mediated inhibition of HBV in vivo.\n","tags":null,"title":"APOBEC3-independent interferon-induced viral clearance in hepatitis B virus transgenic mice.\n","type":"publication"},{"authors":["Keith Reeves","Fultz"],"categories":null,"content":"","date":1193875200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1193875200,"objectID":"bae4e2b7829668a15ce2f68fa6c8e4b7","permalink":"/publication/17989338/","publishdate":"2007-11-01T00:00:00Z","relpermalink":"/publication/17989338/","section":"publication","summary":"Plasmacytoid dendritic cells (pDCs), one of two types of bone marrow (BM)-derived blood DCs, play an important role in linking innate and adaptive immune responses. However, little is known about the nature of pDCs that reside in the BM. Because the simian immunodeficiency virus-macaque model closely mimics human immunodeficiency virus disease in humans, with both infections inducing a decrease in pDCs, we characterized and compared pDCs in the BM with those in peripheral blood (PB) of healthy pig-tailed macaques. The results revealed that pDCs from both compartments had the same CD123++ HLA-DR+ Lin- phenotype and were similar in size. Although BM-derived pDCs (BM-pDCs) were 3-fold greater in frequency and 10-fold greater in number, they had lower cell surface expression of both HLA-DR and the costimulatory molecule CD86 than did PB-pDCs. Both BM- and PB-pDCs responded ex vivo to synthetic CpG oligodeoxynucleotides and inactivated influenza virus by upregulating HLA-DR and CD86 and secreting cytokines; however, stimulated BM-pDCs secreted less alpha interferon and tumor necrosis factor alpha per cell than did PB-pDCs. These results suggest that while BM-pDCs appear to be phenotypically less mature than PB-pDCs, they do respond to pathogens. Thus, during acute infections, these cells could initiate immune responses either in the BM or after rapidly migrating from the BM into the periphery. A better characterization of pDCs in blood and tissues will be beneficial for future studies of macaques that focus on either pathogenesis or vaccine development.\n","tags":null,"title":"Characterization of plasmacytoid dendritic cells in bone marrow of pig-tailed macaques.\n","type":"publication"},{"authors":["Stephanie Jost","Turelli","Mangeat","Protzer","Trono"],"categories":null,"content":"","date":1183248000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1183248000,"objectID":"7209c51b518bdb045ee03ade2c842c0b","permalink":"/publication/17652382/","publishdate":"2007-07-01T00:00:00Z","relpermalink":"/publication/17652382/","section":"publication","summary":"Interferons (IFNs) play a major role in the control of hepatitis B virus (HBV), whether as endogenous cytokines limiting the spread of the virus during the acute phase of the infection or as drugs for the treatment of its chronic phase. However, the mechanism by which IFNs inhibit HBV replication has so far remained elusive. Here, we show that type I and II IFN treatment of human hepatocytes induces the production of APOBEC3G (A3G) and, to a lesser extent, that of APOBEC3F (A3F) and APOBEC3B (A3B) but not that of two other cytidine deaminases also endowed with anti-HBV activity, activation-induced cytidine deaminase (AID), and APOBEC1. Most importantly, we reveal that blocking A3B, A3F, and A3G by combining RNA interference and the virion infectivity factor (Vif) protein of human immunodeficiency virus does not abrogate the inhibitory effect of IFNs on HBV. We conclude that these cytidine deaminases are not essential effectors of IFN in its action against this pathogen.\n","tags":null,"title":"Induction of antiviral cytidine deaminases does not explain the inhibition of hepatitis B virus replication by interferons.\n","type":"publication"},{"authors":["Keith Reeves","Fultz"],"categories":null,"content":"","date":1177977600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1177977600,"objectID":"bb697c4175e50af08c284f3ae4537eae","permalink":"/publication/17490699/","publishdate":"2007-05-01T00:00:00Z","relpermalink":"/publication/17490699/","section":"publication","summary":"Blood plasmacytoid dendritic cells (pDCs) contribute to both innate and adaptive immune responses by secreting high levels of IFN-alpha following acute bacterial and viral infections and indirectly by augmenting cell-mediated immunity. Cross-sectional studies have shown that the number of circulating pDCs in HIV patients, compared to that in uninfected individuals, is reduced. However, since the time of infection is usually unknown in HIV-infected patients, pDC-virus interactions that occur immediately after virus exposure are poorly understood. The current study investigated pDC dynamics during acute and chronic infections of macaques with either SIVmac239 or the pathogenic SIV-HIV chimera, SHIV-89.6P, as models for HIV infection. In three rhesus and three pig-tailed macaques infected intravenously with SIVmac239, the percentages of pDCs in blood declined 2- to 6-fold during the first 6 weeks after infection and remained depressed throughout the disease course. Surprisingly, no consistent, comparable decline in peripheral blood pDCs was observed in six macaques infected with SHIV-89.6P. In this latter group, percentages of pDCs did not correlate with CD4(+) T cells, but there was an inverse relationship with viral load. In addition, when compared to nave controls, the percentages of pDCs were reduced in spleens and peripheral lymph nodes of SIVmac239- but not SHIV-89.6P-infected animals that had progressed to AIDS. Proviral DNA was detected during the acute phase in pDCs isolated from macaques infected with either virus. These results imply that, even though macaque pDCs can be infected by both SIVmac239 and SHIV-89.6P, the subsequent effects on in vivo pathogenesis differ. The underlying mechanism(s) for these differences is unclear, but the selection of SIV or SHIV as a challenge virus might influence the outcome of some studies, such as those evaluating vaccines or the therapeutic efficacy of drugs.\n","tags":null,"title":"Disparate effects of acute and chronic infection with SIVmac239 or SHIV-89.6P on macaque plasmacytoid dendritic cells.\n","type":"publication"},{"authors":["Yerly","Stephanie Jost","Monnat","Telenti","Cavassini","Chave","Kaiser","Burgisser","Perrin","Swiss"],"categories":null,"content":"","date":1088640000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1088640000,"objectID":"f497e9680f4378e7618ccb3a2f7b1f65","permalink":"/publication/15199317/","publishdate":"2004-07-01T00:00:00Z","relpermalink":"/publication/15199317/","section":"publication","summary":"BACKGROUND: The frequency of HIV-1 co/super-infection is unknown despite their implications for public health and vaccine development. This issue was addressed during an epidemic of both CRF11 and B subtype among intravenous drug users (IVDUs). METHODS: Bulk sequencing of reverse transcriptase, protease and C2V3 regions and subtype-specific nested polymerase chain reaction (PCR) in plasma and proviral DNA were performed using baseline and follow-up samples collected in recently infected IVDUs between 1998-2002 and in IVDUs with chronic infection living in the same area and presenting an unexpected rise of viremia ( 1 log10). RESULTS: In 58 recently infected patients, three B/CRF-11 co-infections, 25 B, 28 CRF-11 and two other subtypes were detected at baseline. In the three co-infected patients, both CRF-11 and B were detected in plasma and proviral DNA and persisted during follow-up. B- and CFR-11-specific PCR performed on follow-up samples of 40 of 58 recently infected patients (median follow-up, 14.5 months) revealed a transient B super-infection in a patient initially infected by CRF-11. Five of 156 chronic IVDUs (total follow-up: 346 years) had an unexpected rise of viremia. In two of them, aviremic without treatment for years after an initial B infection, a symptomatic CRF-11 super-infection occurred and was associated with high viral load and a fall of CD4 cell count. CONCLUSIONS: In recently infected IVDUs, co-infection B/CRF-11 is relatively frequent (5%). In chronically infected IVDUs super-infection may be transient and may occur in patients controlling efficiently HIV infection by the initial strain. ","tags":null,"title":"HIV-1 co/super-infection in intravenous drug users.\n","type":"publication"},{"authors":["Yerly","Stephanie Jost","Telenti","Flepp","Kaiser","Chave","Vernazza","Battegay","Furrer","Chanzy","Burgisser","Rickenbach","Gebhardt","Bernard","Perneger","Hirschel","Perrin","Swiss"],"categories":null,"content":"","date":1086048000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1086048000,"objectID":"c082bbe45c77e7fd57f31b4b139752b3","permalink":"/publication/15259900/","publishdate":"2004-06-01T00:00:00Z","relpermalink":"/publication/15259900/","section":"publication","summary":"Transmission of drug-resistant variants is influenced by several factors, including the prevalence of drug resistance in the population of HIV-1-infected patients, HIV-1 RNA levels and transmission by recently infected patients. In order to evaluate the impact of these factors on the transmission of drug-resistant variants, we have defined the population of potential transmitters and compared their resistance profiles to those of newly infected patients. Sequencing of pol gene was performed in 220 recently infected patients and in 373 chronically infected patients with HIV-1 RNA 1000 copies/ml. Minimal and maximal drug-resistance profiles of potential transmitters were estimated by weighting resistance profiles of chronically infected patients with estimates of the Swiss HIV-1-infected population, the prevalence of exposure to antiviral drugs and the proportion of infections attributed to primary HIV infections. The drug-resistance prevalence in recently infected patients was 10.5% (one class drug resistance: 9.1%; two classes: 1.4%; three classes: 0%). Phylogenetic analysis revealed significant clustering for 30% of recent infections. The drug-resistance prevalence in chronically infected patients was 72.4% (one class: 29%; two classes: 27.6%; three classes: 15.8%). After adjustment, the risk of transmission relative to wild-type was reduced both for one class drug resistance (minimal and maximal estimates: odds ratio: 0.39, P","tags":null,"title":"Infrequent transmission of HIV-1 drug-resistant variants.\n","type":"publication"},{"authors":["Turelli","Mangeat","Stephanie Jost","Vianin","Trono"],"categories":null,"content":"","date":1078099200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1078099200,"objectID":"b7fc0e1c0ae9ff38fbdf6e6d6897daae","permalink":"/publication/15031497/","publishdate":"2004-03-01T00:00:00Z","relpermalink":"/publication/15031497/","section":"publication","summary":"PMID: 15031497 [PubMed - indexed for MEDLINE]\n","tags":null,"title":"Inhibition of hepatitis B virus replication by APOBEC3G.\n","type":"publication"},{"authors":["Stephanie Jost","Bernard","Kaiser","Yerly","Hirschel","Samri","Autran","Goh","Perrin"],"categories":null,"content":"","date":1030838400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1030838400,"objectID":"84a0c6ac820167c493f69b01c568cb0a","permalink":"/publication/12213944/","publishdate":"2002-09-01T00:00:00Z","relpermalink":"/publication/12213944/","section":"publication","summary":"PMID: 12213944 [PubMed - indexed for MEDLINE]\n","tags":null,"title":"A patient with HIV-1 superinfection.\n","type":"publication"}]