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Fonseca JA, King AC, Chahroudi A. More than the Infinite Monkey Theorem: NHP Models in the Development of a Pediatric HIV Cure. Curr HIV/AIDS Rep 2024; 21:11-29. [PMID: 38227162 PMCID: PMC10859349 DOI: 10.1007/s11904-023-00686-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2023] [Indexed: 01/17/2024]
Abstract
PURPOSE OF REVIEW An HIV cure that eliminates the viral reservoir or provides viral control without antiretroviral therapy (ART) is an urgent need in children as they face unique challenges, including lifelong ART adherence and the deleterious effects of chronic immune activation. This review highlights the importance of nonhuman primate (NHP) models in developing an HIV cure for children as these models recapitulate the viral pathogenesis and persistence. RECENT FINDINGS Several cure approaches have been explored in infant NHPs, although knowledge gaps remain. Broadly neutralizing antibodies (bNAbs) show promise for controlling viremia and delaying viral rebound after ART interruption but face administration challenges. Adeno-associated virus (AAV) vectors hold the potential for sustained bNAb expression. Therapeutic vaccination induces immune responses against simian retroviruses but has yet to impact the viral reservoir. Combining immunotherapies with latency reversal agents (LRAs) that enhance viral antigen expression should be explored. Current and future cure approaches will require adaptation for the pediatric immune system and unique features of virus persistence, for which NHP models are fundamental to assess their efficacy.
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Affiliation(s)
- Jairo A Fonseca
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Alexis C King
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Ann Chahroudi
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA.
- Emory National Primate Research Center, Emory University, Atlanta, GA, USA.
- Emory+Children's Center for Childhood Infections and Vaccines, Atlanta, GA, USA.
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2
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Dias J, Fabozzi G, March K, Asokan M, Almasri CG, Fintzi J, Promsote W, Nishimura Y, Todd JP, Lifson JD, Martin MA, Gama L, Petrovas C, Pegu A, Mascola JR, Koup RA. Concordance of immunological events between intrarectal and intravenous SHIVAD8-EO infection when assessed by Fiebig-equivalent staging. J Clin Invest 2021; 131:e151632. [PMID: 34623326 PMCID: PMC8409578 DOI: 10.1172/jci151632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 07/22/2021] [Indexed: 11/17/2022] Open
Abstract
Primary HIV-1 infection can be classified into six Fiebig stages based on virological and serological laboratory testing, whereas simian-HIV (SHIV) infection in nonhuman primates (NHPs) is defined in time post-infection, making it difficult to extrapolate NHP experiments to the clinics. We identified and extensively characterized the Fiebig-equivalent stages in NHPs challenged intrarectally or intravenously with SHIVAD8-EO. During the first month post-challenge, intrarectally challenged monkeys were up to 1 week delayed in progression through stages. However, regardless of the challenge route, stages I-II predominated before, and stages V-VI predominated after, peak viremia. Decrease in lymph node (LN) CD4+ T cell frequency and rise in CD8+ T cells occurred at stage V. LN virus-specific CD8+ T cell responses, dominated by degranulation and TNF, were first detected at stage V and increased at stage VI. A similar late elevation in follicular CXCR5+ CD8+ T cells occurred, consistent with higher plasma CXCL13 levels at these stages. LN SHIVAD8-EO RNA+ cells were present at stage II, but appeared to decline at stage VI when virions accumulated in follicles. Fiebig-equivalent staging of SHIVAD8-EO infection revealed concordance of immunological events between intrarectal and intravenous infection despite different infection progressions, and can inform comparisons of NHP studies with clinical data.
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Affiliation(s)
- Joana Dias
- Immunology Laboratory, Vaccine Research Center
| | | | - Kylie March
- Tissue Analysis Core, Vaccine Research Center
| | | | | | | | | | | | - John-Paul Todd
- Translational Research Program, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA
| | - Jeffrey D. Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | | | - Lucio Gama
- Immunology Laboratory, Vaccine Research Center
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3
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Interests of the Non-Human Primate Models for HIV Cure Research. Vaccines (Basel) 2021; 9:vaccines9090958. [PMID: 34579195 PMCID: PMC8472852 DOI: 10.3390/vaccines9090958] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/19/2021] [Accepted: 08/24/2021] [Indexed: 12/17/2022] Open
Abstract
Non-human primate (NHP) models are important for vaccine development and also contribute to HIV cure research. Although none of the animal models are perfect, NHPs enable the exploration of important questions about tissue viral reservoirs and the development of intervention strategies. In this review, we describe recent advances in the use of these models for HIV cure research and highlight the progress that has been made as well as limitations using these models. The main NHP models used are (i) the macaque, in which simian immunodeficiency virus (SIVmac) infection displays similar replication profiles as to HIV in humans, and (ii) the macaque infected by a recombinant virus (SHIV) consisting of SIVmac expressing the HIV envelope gene serving for studies analyzing the impact of anti-HIV Env broadly neutralizing antibodies. Lessons for HIV cure that can be learned from studying the natural host of SIV are also presented here. An overview of the most promising and less well explored HIV cure strategies tested in NHP models will be given.
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Huang M, Yang J, Li P, Chen Y. Embryo-Engineered Nonhuman Primate Models: Progress and Gap to Translational Medicine. RESEARCH (WASHINGTON, D.C.) 2021; 2021:9898769. [PMID: 34549187 PMCID: PMC8404551 DOI: 10.34133/2021/9898769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 08/01/2021] [Indexed: 12/17/2022]
Abstract
Animal models of human diseases are vital in better understanding the mechanism of pathogenesis and essential for evaluating and validating potential therapeutic interventions. As close relatives of humans, nonhuman primates (NHPs) play an increasingly indispensable role in advancing translational medicine research. In this review, we summarized the progress of NHP models generated by embryo engineering, analyzed their unique advantages in mimicking clinical patients, and discussed the remaining gap between basic research of NHP models to translational medicine.
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Affiliation(s)
- Mei Huang
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, China
- State Key Laboratory of Primate Biomedical Research, Kunming 650500, China
| | - Jiao Yang
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, China
- State Key Laboratory of Primate Biomedical Research, Kunming 650500, China
| | - Peng Li
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, China
- State Key Laboratory of Primate Biomedical Research, Kunming 650500, China
| | - Yongchang Chen
- Yunnan Key Laboratory of Primate Biomedical Research, Institute of Primate Translational Medicine, Kunming University of Science and Technology, Kunming 650500, China
- State Key Laboratory of Primate Biomedical Research, Kunming 650500, China
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5
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Okoye AA, Duell DD, Fukazawa Y, Varco-Merth B, Marenco A, Behrens H, Chaunzwa M, Selseth AN, Gilbride RM, Shao J, Edlefsen PT, Geleziunas R, Pinkevych M, Davenport MP, Busman-Sahay K, Nekorchuk M, Park H, Smedley J, Axthelm MK, Estes JD, Hansen SG, Keele BF, Lifson JD, Picker LJ. CD8+ T cells fail to limit SIV reactivation following ART withdrawal until after viral amplification. J Clin Invest 2021; 131:141677. [PMID: 33630764 PMCID: PMC8262469 DOI: 10.1172/jci141677] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 02/23/2021] [Indexed: 12/15/2022] Open
Abstract
To define the contribution of CD8+ T cell responses to control of SIV reactivation during and following antiretroviral therapy (ART), we determined the effect of long-term CD8+ T cell depletion using a rhesusized anti-CD8β monoclonal antibody on barcoded SIVmac239 dynamics on stable ART and after ART cessation in rhesus macaques (RMs). Among the RMs with full CD8+ T cell depletion in both blood and tissue, there were no significant differences in the frequency of viral blips in plasma, the number of SIV RNA+ cells and the average number of RNA copies/infected cell in tissue, and levels of cell-associated SIV RNA and DNA in blood and tissue relative to control-treated RMs during ART. Upon ART cessation, both CD8+ T cell-depleted and control RMs rebounded in fewer than 12 days, with no difference in the time to viral rebound or in either the number or growth rate of rebounding SIVmac239M barcode clonotypes. However, effectively CD8+ T cell-depleted RMs showed a stable, approximately 2-log increase in post-ART plasma viremia relative to controls. These results indicate that while potent antiviral CD8+ T cell responses can develop during ART-suppressed SIV infection, these responses effectively intercept post-ART SIV rebound only after systemic viral replication, too late to limit reactivation frequency or the early spread of reactivating SIV reservoirs.
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Affiliation(s)
- Afam A. Okoye
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Derick D. Duell
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Yoshinori Fukazawa
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Benjamin Varco-Merth
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Alejandra Marenco
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Hannah Behrens
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Morgan Chaunzwa
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Andrea N. Selseth
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Roxanne M. Gilbride
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Jason Shao
- Statistical Center for HIV/AIDS Research and Prevention, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Paul T. Edlefsen
- Statistical Center for HIV/AIDS Research and Prevention, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | | | - Mykola Pinkevych
- Kirby Institute for Infection and Immunity, University of New South Wales, Sydney, New South Wales, Australia
| | - Miles P. Davenport
- Kirby Institute for Infection and Immunity, University of New South Wales, Sydney, New South Wales, Australia
| | - Kathleen Busman-Sahay
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Michael Nekorchuk
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Haesun Park
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Jeremy Smedley
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Michael K. Axthelm
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Jacob D. Estes
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Scott G. Hansen
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
| | - Brandon F. Keele
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
- Leidos Biomedical Research, Inc., Frederick, Maryland, USA
| | - Jeffery D. Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
- Leidos Biomedical Research, Inc., Frederick, Maryland, USA
| | - Louis J. Picker
- Vaccine and Gene Therapy Institute and
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, Oregon, USA
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6
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Infection of Chinese Rhesus Monkeys with a Subtype C SHIV Resulted in Attenuated In Vivo Viral Replication Despite Successful Animal-to-Animal Serial Passages. Viruses 2021; 13:v13030397. [PMID: 33801437 PMCID: PMC7998229 DOI: 10.3390/v13030397] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 02/22/2021] [Accepted: 02/24/2021] [Indexed: 01/23/2023] Open
Abstract
Rhesus macaques can be readily infected with chimeric simian-human immunodeficiency viruses (SHIV) as a suitable virus challenge system for testing the efficacy of HIV vaccines. Three Chinese-origin rhesus macaques (ChRM) were inoculated intravenously (IV) with SHIVC109P4 in a rapid serial in vivo passage. SHIV recovered from the peripheral blood of the final ChRM was used to generate a ChRM-adapted virus challenge stock. This stock was titrated for the intrarectal route (IR) in 8 ChRMs using undiluted, 1:10 or 1:100 dilutions, to determine a suitable dose for use in future vaccine efficacy testing via repeated low-dose IR challenges. All 11 ChRMs were successfully infected, reaching similar median peak viraemias at 1–2 weeks post inoculation but undetectable levels by 8 weeks post inoculation. T-cell responses were detected in all animals and Tier 1 neutralizing antibodies (Nab) developed in 10 of 11 infected ChRMs. All ChRMs remained healthy and maintained normal CD4+ T cell counts. Sequence analyses showed >98% amino acid identity between the original inoculum and virus recovered at peak viraemia indicating only minimal changes in the env gene. Thus, while replication is limited over time, our adapted SHIV can be used to test for protection of virus acquisition in ChRMs.
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7
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Raehtz KD, Barrenäs F, Xu C, Busman-Sahay K, Valentine A, Law L, Ma D, Policicchio BB, Wijewardana V, Brocca-Cofano E, Trichel A, Gale M, Keele BF, Estes JD, Apetrei C, Pandrea I. African green monkeys avoid SIV disease progression by preventing intestinal dysfunction and maintaining mucosal barrier integrity. PLoS Pathog 2020; 16:e1008333. [PMID: 32119719 PMCID: PMC7077871 DOI: 10.1371/journal.ppat.1008333] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 03/17/2020] [Accepted: 01/18/2020] [Indexed: 12/12/2022] Open
Abstract
Unlike HIV infection, SIV infection is generally nonpathogenic in natural hosts, such as African green monkeys (AGMs), despite life-long high viral replication. Lack of disease progression was reportedly based on the ability of SIV-infected AGMs to prevent gut dysfunction, avoiding microbial translocation and the associated systemic immune activation and chronic inflammation. Yet, the maintenance of gut integrity has never been documented, and the mechanism(s) by which gut integrity is preserved are unknown. We sought to investigate the early events of SIV infection in AGMs, specifically examining the impact of SIVsab infection on the gut mucosa. Twenty-nine adult male AGMs were intrarectally infected with SIVsab92018 and serially sacrificed at well-defined stages of SIV infection, preramp-up (1-3 days post-infection (dpi)), ramp-up (4-6 dpi), peak viremia (9-12 dpi), and early chronic SIV infection (46-55 dpi), to assess the levels of immune activation, apoptosis, epithelial damage and microbial translocation in the GI tract and peripheral lymph nodes. Tissue viral loads, plasma cytokines and plasma markers of gut dysfunction were also measured throughout the course of early infection. While a strong, but transient, interferon-based inflammatory response was observed, the levels of plasma markers linked to enteropathy did not increase. Accordingly, no significant increases in apoptosis of either mucosal enterocytes or lymphocytes, and no damage to the mucosal epithelium were documented during early SIVsab infection of AGMs. These findings were supported by RNAseq of the gut tissue, which found no significant alterations in gene expression that would indicate microbial translocation. Thus, for the first time, we confirmed that gut epithelial integrity is preserved, with no evidence of microbial translocation, in AGMs throughout early SIVsab infection. This might protect AGMs from developing intestinal dysfunction and the subsequent chronic inflammation that drives both HIV disease progression and HIV-associated comorbidities.
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Affiliation(s)
- Kevin D. Raehtz
- Division of Infectious Diseases, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Fredrik Barrenäs
- Department of Microbiology, University of Washington, Seattle, Washington, United States of America
- Department of Cell and Molecular Biology, Uppsala University, Uppsala, Sweden
| | - Cuiling Xu
- Division of Infectious Diseases, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Kathleen Busman-Sahay
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Portland, Oregon, United States of America
- Oregon National Primate Research Center, Oregon Health and Science University, Portland, Oregon, United States of America
| | - Audrey Valentine
- Division of Infectious Diseases, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Lynn Law
- Department of Immunology, University of Washington, Seattle, Washington, United States of America
- Center for Innate Immunity and Immune Diseases, University of Washington, Washington, United States of America
| | - Dongzhu Ma
- Department of Orthopedic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Benjamin B. Policicchio
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Viskam Wijewardana
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Egidio Brocca-Cofano
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Anita Trichel
- Division of Laboratory Animal Resources, School of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Michael Gale
- Department of Immunology, University of Washington, Seattle, Washington, United States of America
- Center for Innate Immunity and Immune Diseases, University of Washington, Washington, United States of America
- Washington National Primate Research Center, University of Washington, Seattle, Washington, United States of America
| | - Brandon F. Keele
- AIDS and Cancer Virus Program, Frederick National Laboratory of Cancer Research, Frederick, Maryland, United States of America
| | - Jacob D. Estes
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Portland, Oregon, United States of America
- Oregon National Primate Research Center, Oregon Health and Science University, Portland, Oregon, United States of America
| | - Cristian Apetrei
- Division of Infectious Diseases, Department of Medicine, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Ivona Pandrea
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
- Department of Infectious Diseases and Microbiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
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8
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Long S, Fennessey CM, Newman L, Reid C, O'Brien SP, Li Y, Del Prete GQ, Lifson JD, Gorelick RJ, Keele BF. Evaluating the Intactness of Persistent Viral Genomes in Simian Immunodeficiency Virus-Infected Rhesus Macaques after Initiating Antiretroviral Therapy within One Year of Infection. J Virol 2019; 94:e01308-19. [PMID: 31597776 PMCID: PMC6912123 DOI: 10.1128/jvi.01308-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 09/19/2019] [Indexed: 02/07/2023] Open
Abstract
The major obstacle to more-definitive treatment for HIV infection is the early establishment of virus that persists despite long-term combination antiretroviral therapy (cART) and can cause recrudescent viremia if cART is interrupted. Previous studies of HIV DNA that persists despite cART indicated that only a small fraction of persistent viral sequences was intact. Experimental simian immunodeficiency virus (SIV) infections of nonhuman primates (NHPs) are essential models for testing interventions designed to reduce the viral reservoir. We studied the viral genomic integrity of virus that persists during cART under conditions typical of many NHP reservoir studies, specifically with cART started within 1 year postinfection and continued for at least 9 months. The fraction of persistent DNA in SIV-infected NHPs starting cART during acute or chronic infection was assessed with a multiamplicon, real-time PCR assay designed to analyze locations that are regularly spaced across the viral genome to maximize coverage (collectively referred to as "tile assay") combined with near-full-length (nFL) single-genome sequencing. The tile assay is used to rapidly screen for major deletions, with nFL sequence analysis used to identify additional potentially inactivating mutations. Peripheral blood mononuclear cells (PBMC) from animals started on cART within 1 month of infection, sampled at least 9 months after cART initiation, contained at least 80% intact genomes, whereas those from animals started on cART 1 year postinfection and treated for 1 year contained intact genomes only 47% of the time. The most common defect identified was large deletions, with the remaining defects caused by APOBEC-mediated mutations, frameshift mutations, and inactivating point mutations. Overall, this approach can be used to assess the intactness of persistent viral DNA in NHPs.IMPORTANCE Molecularly defining the viral reservoir that persists despite antiretroviral therapy and that can lead to rebound viremia if antiviral therapy is removed is critical for testing interventions aimed at reducing this reservoir. In HIV infection in humans with delayed treatment initiation and extended treatment duration, persistent viral DNA has been shown to be dominated by nonfunctional genomes. Using multiple real-time PCR assays across the genome combined with near-full-genome sequencing, we defined SIV genetic integrity after 9 to 18 months of combination antiretroviral therapy in rhesus macaques starting therapy within 1 year of infection. In the animals starting therapy within a month of infection, the vast majority of persistent DNA was intact and presumptively functional. Starting therapy within 1 year increased the nonintact fraction of persistent viral DNA. The approach described here allows rapid screening of viral intactness and is a valuable tool for assessing the efficacy of novel reservoir-reducing interventions.
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Affiliation(s)
- Samuel Long
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Christine M Fennessey
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Laura Newman
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Carolyn Reid
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Sean P O'Brien
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Yuan Li
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Gregory Q Del Prete
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Robert J Gorelick
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
| | - Brandon F Keele
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, Maryland, USA
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9
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Bender AM, Simonetti FR, Kumar MR, Fray EJ, Bruner KM, Timmons AE, Tai KY, Jenike KM, Antar AAR, Liu PT, Ho YC, Raugi DN, Seydi M, Gottlieb GS, Okoye AA, Del Prete GQ, Picker LJ, Mankowski JL, Lifson JD, Siliciano JD, Laird GM, Barouch DH, Clements JE, Siliciano RF. The Landscape of Persistent Viral Genomes in ART-Treated SIV, SHIV, and HIV-2 Infections. Cell Host Microbe 2019; 26:73-85.e4. [PMID: 31295427 DOI: 10.1016/j.chom.2019.06.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/21/2019] [Accepted: 05/31/2019] [Indexed: 12/27/2022]
Abstract
Evaluation of HIV cure strategies is complicated by defective proviruses that persist in ART-treated patients but are irrelevant to cure. Non-human primates (NHP) are essential for testing cure strategies. However, the persisting proviral landscape in ART-treated NHPs is uncharacterized. Here, we describe viral genomes persisting in ART-treated, simian immunodeficiency virus (SIV)-infected NHPs, simian-human immunodeficiency virus (SHIV)-infected NHPs, and humans infected with HIV-2, an SIV-related virus. The landscapes of persisting SIV, SHIV, and HIV-2 genomes are also dominated by defective sequences. However, there was a significantly higher fraction of intact SIV proviral genomes compared to ART-treated HIV-1 or HIV-2 infected humans. Compared to humans with HIV-1, SIV-infected NHPs had more hypermutated genomes, a relative paucity of clonal SIV sequences, and a lower frequency of deleted genomes. Finally, we report an assay for measuring intact SIV genomes which may have value in cure research.
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Affiliation(s)
- Alexandra M Bender
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Francesco R Simonetti
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Mithra R Kumar
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Emily J Fray
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Katherine M Bruner
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Andrew E Timmons
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Katherine Y Tai
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Katharine M Jenike
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Annukka A R Antar
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Po-Ting Liu
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Ya-Chi Ho
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Dana N Raugi
- Department of Medicine & Center of Emerging & Re-Emerging Infectious Diseases, University of Washington, Seattle, WA, USA
| | - Moussa Seydi
- Service de Maladies Infectieuses et Tropicales, CHNU-Fann, Dakar, Senegal
| | - Geoffrey S Gottlieb
- Department of Medicine & Center of Emerging & Re-Emerging Infectious Diseases, University of Washington, Seattle, WA, USA
| | - Afam A Okoye
- Vaccine and Gene Therapy Institute, Oregon Health and Sciences University, Beaverton, OR, USA
| | - Gregory Q Del Prete
- AIDS and Cancer Virus Program, Frederick National Laboratory, Frederick, MD, USA
| | - Louis J Picker
- Vaccine and Gene Therapy Institute, Oregon Health and Sciences University, Beaverton, OR, USA
| | - Joseph L Mankowski
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory, Frederick, MD, USA
| | - Janet D Siliciano
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Greg M Laird
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Accelevir Diagnostics, Baltimore, MD, USA
| | - Dan H Barouch
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Janice E Clements
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Robert F Siliciano
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Howard Hughes Medical Institute, Baltimore, MD 21205, USA.
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10
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Daly MB, Clayton AM, Ruone S, Mitchell J, Dinh C, Holder A, Jolly J, García-Lerma JG, Weed JL. Training rhesus macaques to take daily oral antiretroviral therapy for preclinical evaluation of HIV prevention and treatment strategies. PLoS One 2019; 14:e0225146. [PMID: 31730629 PMCID: PMC6857902 DOI: 10.1371/journal.pone.0225146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 10/29/2019] [Indexed: 11/18/2022] Open
Abstract
Background Macaque models of simian or simian/human immunodeficiency virus (SIV or SHIV) infection are critical for the evaluation of antiretroviral (ARV)-based HIV treatment and prevention strategies. However, modelling human oral ARV administration is logistically challenging and fraught by limited adherence. Here, we developed a protocol for administering daily oral doses of ARVs to macaques with a high rate of compliance. Methods Parameters of positive reinforcement training (PRT), behavioral responses and optimal drug delivery foods were defined in 7 male rhesus macaques (Macaca mulatta). Animals were trained to sit in a specified cage location prior to receiving ARVs, emtricitabine (FTC) and tenofovir alafenamide (TAF), in a blended food mixture, which was followed immediately with a juice chaser. Consistency of daily oral adherence was evaluated in 4 trained macaques receiving clinically equivalent doses of FTC and TAF (20 and 1.5 mg/kg, respectively) in a short-term (1 month) and an extended (6 month) trial. Adherence was monitored using medication diaries and by quantifying intracellular FTC-triphosphate (FTC-TP) and tenofovir-diphosphate (TFV-DP) concentrations in peripheral mononuclear blood cells (PBMCs). Results Trained macaques quickly and consistently took daily oral ARVs for 1 month with an average 99.8% observed adherence. Intracellular concentrations of TFV-DP (median = 845.8 fmol/million cells [range, 620.8–1031.3]) and FTC-TP (median = 367.0 fmol/million cells [range, 289.5–413.5) in PBMCs were consistent with high adherence. Extended treatment with select subjects yielded similar observations for three months (99.5% adherence, 352/356 complete doses taken), although a sudden drop in adherence was observed after splenic biopsy surgery. Conclusions We demonstrate that trained macaques reliably adhere to a daily oral ARV regimen, although unexpected adherence issues are possible. Our approach, using clinical doses of oral FTC and TAF daily, further refines macaque models of HIV treatment and prevention by mimicking the human route and timing of ARV administration.
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Affiliation(s)
- Michele B. Daly
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - April M. Clayton
- Comparative Medicine Branch, Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Susan Ruone
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - James Mitchell
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Chuong Dinh
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Angela Holder
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Julian Jolly
- Comparative Medicine Branch, Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - J. Gerardo García-Lerma
- Laboratory Branch, Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail: (JGGL); (JLW)
| | - James L. Weed
- Comparative Medicine Branch, Division of Scientific Resources, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail: (JGGL); (JLW)
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11
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Ferris AL, Wells DW, Guo S, Del Prete GQ, Swanstrom AE, Coffin JM, Wu X, Lifson JD, Hughes SH. Clonal expansion of SIV-infected cells in macaques on antiretroviral therapy is similar to that of HIV-infected cells in humans. PLoS Pathog 2019; 15:e1007869. [PMID: 31291371 PMCID: PMC6619828 DOI: 10.1371/journal.ppat.1007869] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 05/24/2019] [Indexed: 12/11/2022] Open
Abstract
Clonal expansion of HIV infected cells plays an important role in the formation and persistence of the reservoir that allows the virus to persist, in DNA form, despite effective antiretroviral therapy. We used integration site analysis to ask if there is a similar clonal expansion of SIV infected cells in macaques. We show that the distribution of HIV and SIV integration sites in vitro is similar and that both viruses preferentially integrate in many of the same genes. We obtained approximately 8000 integration sites from blood samples taken from SIV-infected macaques prior to the initiation of ART, and from blood, spleen, and lymph node samples taken at necropsy. Seven clones were identified in the pre-ART samples; one persisted for a year on ART. An additional 100 clones were found only in on-ART samples; a number of these clones were found in more than one tissue. The timing and extent of clonal expansion of SIV-infected cells in macaques and HIV-infected cells in humans is quite similar. This suggests that SIV-infected macaques represent a useful model of the clonal expansion of HIV infected cells in humans that can be used to evaluate strategies intended to control or eradicate the viral reservoir.
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Affiliation(s)
- Andrea L. Ferris
- HIV Dynamics and Replication Program, National Cancer Institute Frederick, National Institutes of Health, Frederick, MD, United States of America
| | - David W. Wells
- Cancer Research Technology Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick MD, United States of America
| | - Shuang Guo
- Cancer Research Technology Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick MD, United States of America
| | - Gregory Q. Del Prete
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, United States of America
| | - Adrienne E. Swanstrom
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, United States of America
| | - John M. Coffin
- Department of Molecular Biology and Microbiology, Tufts University, Boston MA, United States of America
| | - Xiaolin Wu
- Cancer Research Technology Program, Leidos Biomedical Research Inc., Frederick National Laboratory for Cancer Research, Frederick MD, United States of America
| | - Jeffrey D. Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, United States of America
| | - Stephen H. Hughes
- HIV Dynamics and Replication Program, National Cancer Institute Frederick, National Institutes of Health, Frederick, MD, United States of America
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12
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Wagar LE, DiFazio RM, Davis MM. Advanced model systems and tools for basic and translational human immunology. Genome Med 2018; 10:73. [PMID: 30266097 PMCID: PMC6162943 DOI: 10.1186/s13073-018-0584-8] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/17/2018] [Indexed: 12/31/2022] Open
Abstract
There are fundamental differences between humans and the animals we typically use to study the immune system. We have learned much from genetically manipulated and inbred animal models, but instances in which these findings have been successfully translated to human immunity have been rare. Embracing the genetic and environmental diversity of humans can tell us about the fundamental biology of immune cell types and the elasticity of the immune system. Although people are much more immunologically diverse than conventionally housed animal models, tools and technologies are now available that permit high-throughput analysis of human samples, including both blood and tissues, which will give us deep insights into human immunity in health and disease. As we gain a more detailed picture of the human immune system, we can build more sophisticated models to better reflect this complexity, both enabling the discovery of new immunological mechanisms and facilitating translation into the clinic.
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Affiliation(s)
- Lisa E Wagar
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Robert M DiFazio
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Mark M Davis
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, 94305, USA.
- Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, CA, 94305, USA.
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, 94305, USA.
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13
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Marshall VA, Labo N, Hao XP, Holdridge B, Thompson M, Miley W, Brands C, Coalter V, Kiser R, Anver M, Golubeva Y, Warner A, Jaffe ES, Piatak M, Wong SW, Ohlen C, MacAllister R, Smedley J, Deleage C, Del Prete GQ, Lifson JD, Estes JD, Whitby D. Gammaherpesvirus infection and malignant disease in rhesus macaques experimentally infected with SIV or SHIV. PLoS Pathog 2018; 14:e1007130. [PMID: 30001436 PMCID: PMC6042791 DOI: 10.1371/journal.ppat.1007130] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 05/31/2018] [Indexed: 12/22/2022] Open
Abstract
Human gammaherpesviruses are associated with malignancies in HIV infected individuals; in macaques used in non-human primate models of HIV infection, gammaherpesvirus infections also occur. Limited data on prevalence and tumorigenicity of macaque gammaherpesviruses, mostly cross-sectional analyses of small series, are available. We comprehensively examine all three-rhesus macaque gammaherpesviruses -Rhesus rhadinovirus (RRV), Rhesus Lymphocryptovirus (RLCV) and Retroperitoneal Fibromatosis Herpesvirus (RFHV) in macaques experimentally infected with Simian Immunodeficiency Virus or Simian Human Immunodeficiency Virus (SIV/SHIV) in studies spanning 15 years at the AIDS and Cancer Virus Program of the Frederick National Laboratory for Cancer Research. We evaluated 18 animals with malignancies (16 lymphomas, one fibrosarcoma and one carcinoma) and 32 controls. We developed real time quantitative PCR assays for each gammaherpesvirus DNA viral load (VL) in malignant and non-tumor tissues; we also characterized the tumors using immunohistochemistry and in situ hybridization. Furthermore, we retrospectively quantified gammaherpesvirus DNA VL and SIV/SHIV RNA VL in longitudinally-collected PBMCs and plasma, respectively. One or more gammaherpesviruses were detected in 17 tumors; generally, one was predominant, and the relevant DNA VL in the tumor was very high compared to surrounding tissues. RLCV was predominant in tumors resembling diffuse large B cell lymphomas; in a Burkitt-like lymphoma, RRV was predominant; and in the fibrosarcoma, RFHV was predominant. Median RRV and RLCV PBMC DNA VL were significantly higher in cases than controls; SIV/SHIV VL and RLCV VL were independently associated with cancer. Local regressions showed that longitudinal VL patterns in cases and controls, from SIV infection to necropsy, differed for each gammaherpesvirus: while RFHV VL increased only slightly in all animals, RLCV and RRV VL increased significantly and continued to increase steeply in cases; in controls, VL flattened. In conclusion, the data suggest that gammaherpesviruses may play a significant role in tumorogenesis in macaques infected with immunodeficiency viruses.
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Affiliation(s)
- Vickie A. Marshall
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Nazzarena Labo
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Xing-Pei Hao
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
- Pathology/Histotechnology Laboratory, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Benjamin Holdridge
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Marshall Thompson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Wendell Miley
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Catherine Brands
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Vicky Coalter
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Rebecca Kiser
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Miriam Anver
- Pathology/Histotechnology Laboratory, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Yelena Golubeva
- Pathology/Histotechnology Laboratory, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Andrew Warner
- Pathology/Histotechnology Laboratory, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Elaine S. Jaffe
- Laboratory of Pathology, Center for Cancer Research, NCI, Bethesda, Maryland, United States of America
| | - Michael Piatak
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Scott W. Wong
- Vaccine and Gene Therapy Institute, Oregon Health & Sciences University, Beaverton, Oregon, United States of America
| | - Claes Ohlen
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Rhonda MacAllister
- Laboratory Animal Science Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Jeremy Smedley
- Laboratory Animal Science Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Claire Deleage
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Gregory Q. Del Prete
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Jeffrey D. Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Jacob D. Estes
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
| | - Denise Whitby
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Frederick National Laboratory for Cancer Research sponsored by the National Cancer Institute, Frederick, Maryland, United States of America
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