1
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Frumento N, Sinnis-Bourozikas A, Paul HT, Stavrakis G, Zahid MN, Wang S, Ray SC, Flyak AI, Shaw GM, Cox AL, Bailey JR. Neutralizing antibodies evolve to exploit vulnerable sites in the HCV envelope glycoprotein E2 and mediate spontaneous clearance of infection. Immunity 2024; 57:40-51.e5. [PMID: 38171362 PMCID: PMC10874496 DOI: 10.1016/j.immuni.2023.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/28/2023] [Accepted: 12/06/2023] [Indexed: 01/05/2024]
Abstract
Individuals who clear primary hepatitis C virus (HCV) infections clear subsequent reinfections more than 80% of the time, but the mechanisms are poorly defined. Here, we used HCV variants and plasma from individuals with repeated clearance to characterize longitudinal changes in envelope glycoprotein E2 sequences, function, and neutralizing antibody (NAb) resistance. Clearance of infection was associated with early selection of viruses with NAb resistance substitutions that also reduced E2 binding to CD81, the primary HCV receptor. Later, peri-clearance plasma samples regained neutralizing capacity against these variants. We identified a subset of broadly NAbs (bNAbs) for which these loss-of-fitness substitutions conferred resistance to unmutated bNAb ancestors but increased sensitivity to mature bNAbs. These data demonstrate a mechanism by which neutralizing antibodies contribute to repeated immune-mediated HCV clearance, identifying specific bNAbs that exploit fundamental vulnerabilities in E2. The induction of bNAbs with these specificities should be a goal of HCV vaccine development.
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Affiliation(s)
- Nicole Frumento
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Ariadne Sinnis-Bourozikas
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Harry T Paul
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Georgia Stavrakis
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Muhammad N Zahid
- University of Bahrain, Department of Biology, College of Science, Sakhir Campus, Sakhir, Bahrain
| | - Shuyi Wang
- Department of Medicine and Department of Microbiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Stuart C Ray
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Andrew I Flyak
- Department of Microbiology and Immunology, Cornell University, Ithaca, NY, USA
| | - George M Shaw
- Department of Medicine and Department of Microbiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrea L Cox
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Justin R Bailey
- Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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2
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Paneerselvam N, Khan A, Lawson BR. Broadly neutralizing antibodies targeting HIV: Progress and challenges. Clin Immunol 2023; 257:109809. [PMID: 37852345 PMCID: PMC10872707 DOI: 10.1016/j.clim.2023.109809] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/05/2023] [Accepted: 10/11/2023] [Indexed: 10/20/2023]
Abstract
Anti-HIV broadly neutralizing antibodies (bNAbs) offer a novel approach to treating, preventing, or curing HIV. Pre-clinical models and clinical trials involving the passive transfer of bNAbs have demonstrated that they can control viremia and potentially serve as alternatives or complement antiretroviral therapy (ART). However, antibody decay, persistent latent reservoirs, and resistance impede bNAb treatment. This review discusses recent advancements and obstacles in applying bNAbs and proposes strategies to enhance their therapeutic potential. These strategies include multi-epitope targeting, antibody half-life extension, combining with current and newer antiretrovirals, and sustained antibody secretion.
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Affiliation(s)
| | - Amber Khan
- The Scintillon Research Institute, 6868 Nancy Drive, San Diego, CA 92121, USA
| | - Brian R Lawson
- The Scintillon Research Institute, 6868 Nancy Drive, San Diego, CA 92121, USA.
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3
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Otte F, Zhang Y, Spagnuolo J, Thielen A, Däumer M, Wiethe C, Stoeckle M, Kusejko K, Klein F, Metzner KJ, Klimkait T. Revealing viral and cellular dynamics of HIV-1 at the single-cell level during early treatment periods. Cell Rep Methods 2023; 3:100485. [PMID: 37426753 PMCID: PMC10326345 DOI: 10.1016/j.crmeth.2023.100485] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 01/30/2023] [Accepted: 04/28/2023] [Indexed: 07/11/2023]
Abstract
While combination therapy completely suppresses HIV-1 replication in blood, functional virus persists in CD4+ T cell subsets in non-peripheral compartments that are not easily accessible. To fill this gap, we investigated tissue-homing properties of cells that transiently appear in the circulating blood. Through cell separation and in vitro stimulation, the HIV-1 "Gag and Envelope reactivation co-detection assay" (GERDA) enables sensitive detection of Gag+/Env+ protein-expressing cells down to about one cell per million using flow cytometry. By associating GERDA with proviral DNA and polyA-RNA transcripts, we corroborate the presence and functionality of HIV-1 in critical body compartments utilizing t-distributed stochastic neighbor embedding (tSNE) and density-based spatial clustering of applications with noise (DBSCAN) clustering with low viral activity in circulating cells early after diagnosis. We demonstrate transcriptional HIV-1 reactivation at any time, potentially giving rise to intact, infectious particles. With single-cell level resolution, GERDA attributes virus production to lymph-node-homing cells with central memory T cells (TCMs) as main players, critical for HIV-1 reservoir eradication.
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Affiliation(s)
- Fabian Otte
- Molecular Virology, Department Biomedicine, University of Basel, 4009 Basel, Switzerland
| | - Yuepeng Zhang
- Molecular Virology, Department Biomedicine, University of Basel, 4009 Basel, Switzerland
| | - Julian Spagnuolo
- Experimental Immunology, Department Biomedicine, University of Basel, 4056 Basel, Switzerland
| | | | | | | | - Marcel Stoeckle
- Infectiology, University Hospital Basel, 4031 Basel, Switzerland
| | - Katharina Kusejko
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, and Institute of Medical Virology, University of Zurich, 8091 Zurich, Switzerland
| | - Florian Klein
- Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, 50931 Cologne, Germany
| | - Karin J. Metzner
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, and Institute of Medical Virology, University of Zurich, 8091 Zurich, Switzerland
| | - Thomas Klimkait
- Molecular Virology, Department Biomedicine, University of Basel, 4009 Basel, Switzerland
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4
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Boutin M, Medjahed H, Nayrac M, Lotke R, Gendron-Lepage G, Bourassa C, Sauter D, Richard J, Finzi A. Temsavir Modulates HIV-1 Envelope Conformation by Decreasing Its Proteolytic Cleavage. Viruses 2023; 15:1189. [PMID: 37243275 PMCID: PMC10221371 DOI: 10.3390/v15051189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/10/2023] [Accepted: 05/16/2023] [Indexed: 05/28/2023] Open
Abstract
HIV-1 envelope glycoproteins (Envs) mediate viral entry and represent a target of choice for small molecule inhibitors. One of them, temsavir (BMS-626529) prevents the interaction of the host cell receptor CD4 with Env by binding the pocket under the β20-β21 loop of the Env subunit gp120. Along with its capacity to prevent viral entry, temsavir stabilizes Env in its "closed" conformation. We recently reported that temsavir affects glycosylation, proteolytic processing, and overall conformation of Env. Here, we extend these results to a panel of primary Envs and infectious molecular clones (IMCs), where we observe a heterogeneous impact on Env cleavage and conformation. Our results suggest that the effect of temsavir on Env conformation is associated with its capacity to decrease Env processing. Indeed, we found that the effect of temsavir on Env processing affects the recognition of HIV-1-infected cells by broadly neutralizing antibodies and correlates with their capacity to mediate antibody-dependent cellular cytotoxicity (ADCC).
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Affiliation(s)
- Marianne Boutin
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada (M.N.)
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Halima Medjahed
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada (M.N.)
| | - Manon Nayrac
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada (M.N.)
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Rishikesh Lotke
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, 72076 Tübingen, Germany
| | | | | | - Daniel Sauter
- Institute for Medical Virology and Epidemiology of Viral Diseases, University Hospital Tübingen, 72076 Tübingen, Germany
- Institute of Molecular Virology, Ulm University Medical Center, 89081 Ulm, Germany
| | - Jonathan Richard
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada (M.N.)
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H3T 1J4, Canada
| | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada (M.N.)
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H3T 1J4, Canada
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5
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Caniels TG, Medina-Ramírez M, Zhang J, Sarkar A, Kumar S, LaBranche A, Derking R, Allen JD, Snitselaar JL, Capella-Pujol J, Sánchez IDM, Yasmeen A, Diaz M, Aldon Y, Bijl TPL, Venkatayogi S, Martin Beem JS, Newman A, Jiang C, Lee WH, Pater M, Burger JA, van Breemen MJ, de Taeye SW, Rantalainen K, LaBranche C, Saunders KO, Montefiori D, Ozorowski G, Ward AB, Crispin M, Moore JP, Klasse PJ, Haynes BF, Wilson IA, Wiehe K, Verkoczy L, Sanders RW. Germline-targeting HIV-1 Env vaccination induces VRC01-class antibodies with rare insertions. Cell Rep Med 2023; 4:101003. [PMID: 37044090 PMCID: PMC10140475 DOI: 10.1016/j.xcrm.2023.101003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 01/23/2023] [Accepted: 03/17/2023] [Indexed: 04/14/2023]
Abstract
Targeting germline (gl-) precursors of broadly neutralizing antibodies (bNAbs) is acknowledged as an important strategy for HIV-1 vaccines. The VRC01-class of bNAbs is attractive because of its distinct genetic signature. However, VRC01-class bNAbs often require extensive somatic hypermutation, including rare insertions and deletions. We describe a BG505 SOSIP trimer, termed GT1.2, to optimize binding to gl-CH31, the unmutated common precursor of the CH30-34 bNAb lineage that acquired a large CDRH1 insertion. The GT1.2 trimer activates gl-CH31 naive B cells in knock-in mice, and B cell responses could be matured by selected boosting immunogens to generate cross-reactive Ab responses. Next-generation B cell sequencing reveals selection for VRC01-class mutations, including insertions in CDRH1 and FWR3 at positions identical to VRC01-class bNAbs, as well as CDRL1 deletions and/or glycine substitutions to accommodate the N276 glycan. These results provide proof of concept for vaccine-induced affinity maturation of B cell lineages that require rare insertions and deletions.
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Affiliation(s)
- Tom G Caniels
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Max Medina-Ramírez
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Jinsong Zhang
- Applied Biomedical Science Institute, San Diego, CA, USA
| | - Anita Sarkar
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Sonu Kumar
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Alex LaBranche
- Applied Biomedical Science Institute, San Diego, CA, USA
| | - Ronald Derking
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Joel D Allen
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Jonne L Snitselaar
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Joan Capella-Pujol
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Iván Del Moral Sánchez
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Anila Yasmeen
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY, USA
| | - Marilyn Diaz
- Applied Biomedical Science Institute, San Diego, CA, USA
| | - Yoann Aldon
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Tom P L Bijl
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | | | | | - Amanda Newman
- Department of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - Chuancang Jiang
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY, USA
| | - Wen-Hsin Lee
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Maarten Pater
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Judith A Burger
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Mariëlle J van Breemen
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Steven W de Taeye
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands
| | - Kimmo Rantalainen
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Celia LaBranche
- Department of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - Kevin O Saunders
- Department of Surgery, Duke University School of Medicine, Durham, NC, USA
| | - David Montefiori
- Department of Surgery, Duke University School of Medicine, Durham, NC, USA; Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Andrew B Ward
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - John P Moore
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY, USA
| | - Per Johan Klasse
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY, USA
| | - Barton F Haynes
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - Ian A Wilson
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA, USA; The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Kevin Wiehe
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | | | - Rogier W Sanders
- Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands; Amsterdam Institute for Infection and Immunity, Infectious Diseases, Amsterdam, the Netherlands; Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY, USA.
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6
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Baroncini L, Bredl S, Nicole KP, Speck RF. The Humanized Mouse Model: What Added Value Does It Offer for HIV Research? Pathogens 2023; 12:pathogens12040608. [PMID: 37111494 PMCID: PMC10142098 DOI: 10.3390/pathogens12040608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 04/13/2023] [Accepted: 04/14/2023] [Indexed: 04/29/2023] Open
Abstract
In the early 2000s, novel humanized mouse models based on the transplantation of human hematopoietic stem and progenitor cells (HSPCs) into immunocompromised mice were introduced (hu mice). The human HSPCs gave rise to a lymphoid system of human origin. The HIV research community has greatly benefitted from these hu mice. Since human immunodeficiency virus (HIV) type 1 infection results in a high-titer disseminated HIV infection, hu mice have been of great value for all types of HIV research from pathogenesis to novel therapies. Since the first description of this new generation of hu mice, great efforts have been expended to improve humanization by creating other immunodeficient mouse models or supplementing mice with human transgenes to improve human engraftment. Many labs have their own customized hu mouse models, making comparisons quite difficult. Here, we discuss the different hu mouse models in the context of specific research questions in order to define which characteristics should be considered when determining which hu mouse model is appropriate for the question posed. We strongly believe that researchers must first define their research question and then determine whether a hu mouse model exists, allowing the research question to be studied.
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Affiliation(s)
- Luca Baroncini
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital of Zurich, University of Zurich, 8091 Zurich, Switzerland
| | - Simon Bredl
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital of Zurich, University of Zurich, 8091 Zurich, Switzerland
| | - Kadzioch P Nicole
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital of Zurich, University of Zurich, 8091 Zurich, Switzerland
| | - Roberto F Speck
- Department of Infectious Diseases and Hospital Epidemiology, University Hospital of Zurich, University of Zurich, 8091 Zurich, Switzerland
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7
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Laumaea A, Marchitto L, Ding S, Beaudoin-Bussières G, Prévost J, Gasser R, Chatterjee D, Gendron-Lepage G, Medjahed H, Chen HC, Smith AB, Ding H, Kappes JC, Hahn BH, Kirchhoff F, Richard J, Duerr R, Finzi A. Small CD4 mimetics sensitize HIV-1-infected macrophages to antibody-dependent cellular cytotoxicity. Cell Rep 2023; 42:111983. [PMID: 36640355 PMCID: PMC9941794 DOI: 10.1016/j.celrep.2022.111983] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 10/25/2022] [Accepted: 12/22/2022] [Indexed: 01/12/2023] Open
Abstract
HIV-1 envelope (Env) conformation determines the susceptibility of infected CD4+ T cells to antibody-dependent cellular cytotoxicity (ADCC). Upon interaction with CD4, Env adopts more "open" conformations, exposing ADCC epitopes. HIV-1 limits Env-CD4 interaction and protects infected cells against ADCC by downregulating CD4 via Nef, Vpu, and Env. Limited data exist, however, of the role of these proteins in downmodulating CD4 on infected macrophages and how this impacts Env conformation. While Nef, Vpu, and Env are all required to efficiently downregulate CD4 on infected CD4+ T cells, we show here that any one of these proteins is sufficient to downmodulate most CD4 from the surface of infected macrophages. Consistent with this finding, Nef and Vpu have a lesser impact on Env conformation and ADCC sensitivity in infected macrophages compared with CD4+ T cells. However, treatment of infected macrophages with small CD4 mimetics exposes vulnerable CD4-induced Env epitopes and sensitizes them to ADCC.
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Affiliation(s)
- Annemarie Laumaea
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada.
| | - Lorie Marchitto
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Shilei Ding
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada
| | - Guillaume Beaudoin-Bussières
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Jérémie Prévost
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Romain Gasser
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | | | | | | | - Hung-Ching Chen
- Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104-6323, USA
| | - Amos B Smith
- Department of Chemistry, School of Arts and Sciences, University of Pennsylvania, Philadelphia, PA 19104-6323, USA
| | - Haitao Ding
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - John C Kappes
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; Birmingham Veterans Affairs Medical Center, Research Service, Birmingham, AL 35233, USA
| | - Beatrice H Hahn
- Departments of Medicine and Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104-6076, USA
| | - Frank Kirchhoff
- Institute of Molecular Virology, Ulm University Medical Center, Ulm, Germany
| | - Jonathan Richard
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada
| | - Ralf Duerr
- Department of Microbiology, New York University School of Medicine, New York, NY 10016, USA
| | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, QC H2X 0A9, Canada; Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, QC H2X 0A9, Canada.
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8
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Mandizvo T, Gumede N, Ndlovu B, Ndlovu S, Mann JK, Chopera DR, Singh L, Dong KL, Walker BD, Ndhlovu ZM, Lavine CL, Seaman MS, Gounder K, Ndung'u T. Subtle Longitudinal Alterations in Env Sequence Potentiate Differences in Sensitivity to Broadly Neutralizing Antibodies following Acute HIV-1 Subtype C Infection. J Virol 2022; 96:e0127022. [PMID: 36453881 DOI: 10.1128/jvi.01270-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Broadly neutralizing antibodies (bNAbs) for HIV-1 prevention or cure strategies must inhibit transmitted/founder and reservoir viruses. Establishing sensitivity of circulating viruses to bNAbs and genetic patterns affecting neutralization variability may guide rational bNAbs selection for clinical development. We analyzed 326 single env genomes from nine individuals followed longitudinally following acute HIV-1 infection, with samples collected at ~1 week after the first detection of plasma viremia; 300 to 1,709 days postinfection but prior to initiating antiretroviral therapy (ART) (median = 724 days); and ~1 year post ART initiation. Sequences were assessed for phylogenetic relatedness, potential N- and O-linked glycosylation, and variable loop lengths (V1 to V5). A total of 43 env amplicons (median = 3 per patient per time point) were cloned into an expression vector and the TZM-bl assay was used to assess the neutralization profiles of 15 bNAbs targeting the CD4 binding site, V1/V2 region, V3 supersite, MPER, gp120/gp41 interface, and fusion peptide. At 1 μg/mL, the neutralization breadths were as follows: VRC07-LS and N6.LS (100%), VRC01 (86%), PGT151 (81%), 10-1074 and PGT121 (80%), and less than 70% for 10E8, 3BNC117, CAP256.VRC26, 4E10, PGDM1400, and N123-VRC34.01. Features associated with low sensitivity to V1/V2 and V3 bNAbs were higher potential glycosylation sites and/or relatively longer V1 and V4 domains, including known "signature" mutations. The study shows significant variability in the breadth and potency of bNAbs against circulating HIV-1 subtype C envelopes. VRC07-LS, N6.LS, VRC01, PGT151, 10-1074, and PGT121 display broad activity against subtype C variants, and major determinants of sensitivity to most bNAbs were within the V1/V4 domains. IMPORTANCE Broadly neutralizing antibodies (bNAbs) have potential clinical utility in HIV-1 prevention and cure strategies. However, bNAbs target diverse epitopes on the HIV-1 envelope and the virus may evolve to evade immune responses. It is therefore important to identify antibodies with broad activity in high prevalence settings, as well as the genetic patterns that may lead to neutralization escape. We investigated 15 bNAbs with diverse biophysical properties that target six epitopes of the HIV-1 Env glycoprotein for their ability to inhibit viruses that initiated infection, viruses circulating in plasma at chronic infection before antiretroviral treatment (ART), or viruses that were archived in the reservoir during ART in subtype C infected individuals in South Africa, a high burden country. We identify the antibodies most likely to be effective for clinical use in this setting and describe mutational patterns associated with neutralization escape from these antibodies.
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9
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Martin F, Marcelino JM, Palladino C, Bártolo I, Tracana S, Moranguinho I, Gonçalves P, Mateus R, Calado R, Borrego P, Leitner T, Clemente S, Taveira N. Long-Term and Low-Level Envelope C2V3 Stimulation by Highly Diverse Virus Isolates Leads to Frequent Development of Broad and Elite Antibody Neutralization in HIV-1-Infected Individuals. Microbiol Spectr 2022; 10:e0163422. [PMID: 36445130 PMCID: PMC9769935 DOI: 10.1128/spectrum.01634-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 10/29/2022] [Indexed: 12/03/2022] Open
Abstract
A minority of HIV-1-infected patients produce broadly neutralizing antibodies (bNAbs). Identification of viral and host correlates of bNAb production may help develop vaccines. We aimed to characterize the neutralizing response and viral and host-associated factors in Angola, which has one of the oldest, most dynamic, and most diverse HIV-1 epidemics in the world. Three hundred twenty-two HIV-1-infected adults from Angola were included in this retrospective study. Phylogenetic analysis of C2V3C3 env gene sequences was used for virus subtyping. Env-binding antibody reactivity was tested against polypeptides comprising the C2, V3, and C3 regions. Neutralizing-antibody responses were determined against a reference panel of tier 2 Env pseudoviruses in TZM-bl cells; neutralizing epitope specificities were predicted using ClustVis. All subtypes were found, along with untypeable strains and recombinant forms. Notably, 56% of the patients developed cross neutralizing, broadly neutralizing, or elite neutralizing responses. Broad and elite neutralization was associated with longer infection time, subtype C, lower CD4+ T cell counts, higher age, and higher titer of C2V3C3-specific antibodies relative to failure to develop bNAbs. Neutralizing antibodies targeted the V3-glycan supersite in most patients. V3 and C3 regions were significantly less variable in elite neutralizers than in weak neutralizers and nonneutralizers, suggesting an active role of V3C3-directed bNAbs in controlling HIV-1 replication and diversification. In conclusion, prolonged and low-level envelope V3C3 stimulation by highly diverse and ancestral HIV-1 isolates promotes the frequent elicitation of bNAbs. These results provide important clues for the development of an effective HIV-1 vaccine. IMPORTANCE Studies on neutralization by antibodies and their determinants in HIV-1-infected individuals have mostly been conducted in relatively recent epidemics caused by subtype B and C viruses. Results have suggested that elicitation of broadly neutralizing antibodies (bNAbs) is uncommon. The mechanisms underlying the elicitation of bNAbs are still largely unknown. We performed the first characterization of the plasma neutralizing response in a cohort of HIV-1-infected patients from Angola. Angola is characterized by an old and dynamic epidemic caused by highly diverse HIV-1 variants. Remarkably, more than half of the patients produced bNAbs, mostly targeting the V3-glycan supersite in HIV-1. This was associated with higher age, longer infection time, lower CD4+ T cell counts, subtype C infection, or higher titer of C2V3C3-specific antibodies relative to patients that did not develop bNAbs. These results may help develop the next generation of vaccine candidates for HIV-1.
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Affiliation(s)
- Francisco Martin
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - José Maria Marcelino
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
- Centro de Investigação Interdisciplinar Egas Moniz, Instituto Universitário Egas Moniz, Caparica, Portugal
| | - Claudia Palladino
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Inês Bártolo
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Susana Tracana
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Inês Moranguinho
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Paloma Gonçalves
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Rita Mateus
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Rita Calado
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Pedro Borrego
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
| | - Thomas Leitner
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | | | - Nuno Taveira
- Research Institute for Medicine, Faculty of Pharmacy, Universidade de Lisboa, Lisbon, Portugal
- Centro de Investigação Interdisciplinar Egas Moniz, Instituto Universitário Egas Moniz, Caparica, Portugal
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10
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Wang C, Schlub TE, Yu WH, Tan CS, Stefic K, Gianella S, Smith DM, Lauffenburger DA, Chaillon A, Julg B. Landscape of Human Immunodeficiency Virus Neutralization Susceptibilities Across Tissue Reservoirs. Clin Infect Dis 2022; 75:1342-1350. [PMID: 35234862 PMCID: PMC9555844 DOI: 10.1093/cid/ciac164] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Human immunodeficiency virus type 1 (HIV-1) sequence diversity and the presence of archived epitope muta-tions in antibody binding sites are a major obstacle for the clinical application of broadly neutralizing antibodies (bNAbs) against HIV-1. Specifically, it is unclear to what degree the viral reservoir is compartmentalized and if virus susceptibility to antibody neutralization differs across tissues. METHODS The Last Gift cohort enrolled 7 people with HIV diagnosed with a terminal illness and collected antemortem blood and postmortem tissues across 33 anatomical compartments for near full-length env HIV genome sequencing. Using these data, we applied a Bayesian machine-learning model (Markov chain Monte Carlo-support vector machine) that uses HIV-1 envelope sequences and approximated glycan-occupancy information to quantitatively predict the half-maximal inhib-itory concentrations (IC50) of bNAbs, allowing us to map neutralization resistance pattern across tissue reservoirs. RESULTS Predicted mean susceptibilities across tissues within participants were relatively homogenous, and the susceptibility pattern observed in blood often matched what was predicted for tissues. However, selected tissues, such as the brain, showed ev-idence of compartmentalized viral populations with distinct neutralization susceptibilities in some participants. Additionally, we found substantial heterogeneity in the range of neutralization susceptibilities across tissues within and between indi-viduals, and between bNAbs within individuals (standard deviation of log2(IC50) >3.4). CONCLUSIONS Blood-based screening methods to determine viral susceptibility to bNAbs might underestimate the presence of resistant viral variants in tissues. The extent to which these resistant viruses are clinically relevant, that is, lead to bNAb therapeutic failure, needs to be further explored.
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Affiliation(s)
- Chuangqi Wang
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Timothy E Schlub
- University of Sydney, Faculty of Medicine and Health, Sydney School of Public Health, Sydney, New South Wales, Australia
| | - Wen Han Yu
- Bill & Melinda Gates Medical Research Institute, Cambridge, Massachusetts, USA
| | - C Sabrina Tan
- Division of Infectious Diseases, Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
| | - Karl Stefic
- Department of Virology, Tours University Hospital, Tours, France
| | - Sara Gianella
- Division of Infectious Diseases and Global Public Health, University of California–San Diego, San Diego, California, USA
| | - Davey M Smith
- Division of Infectious Diseases and Global Public Health, University of California–San Diego, San Diego, California, USA
- VA San Diego Healthcare System, San Diego, California, USA
| | - Douglas A Lauffenburger
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Antoine Chaillon
- Division of Infectious Diseases and Global Public Health, University of California–San Diego, San Diego, California, USA
| | - Boris Julg
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard University, Cambridge, Massachusetts, USA
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11
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Fortner A, Bucur O. mRNA-based vaccine technology for HIV. Discoveries (Craiova) 2022; 10:e150. [PMID: 36438441 PMCID: PMC9683993 DOI: 10.15190/d.2022.9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 06/28/2022] [Accepted: 06/28/2022] [Indexed: 12/14/2022] Open
Abstract
Human immunodeficiency virus (HIV) poses a major health problem around the globe, resulting in hundred-thousands of deaths from AIDS and over a million new infections annually. Although the standard treatment of HIV infection, antiretroviral therapy, has proven effective in preventing HIV transmission, it is unsuitable for worldwide use due to its substantial costs and frequent adverse effects. Besides promoting HIV/AIDS awareness through education, there is hardly an alternative for inhibiting the spread of the disease. One promising approach is the development of an HIV vaccine. Unfortunately, the high variability of envelope proteins from HIV subtypes, their frequency of mutation and the lack of fully understanding the mechanisms of protection against the virus constitute an obstacle for vaccine development. Efforts for developing successful anti-HIV vaccines have been underway for decades now, with little success. Lately, significant progress has been made in adopting the novel mRNA vaccine approach as an anti-HIV strategy. mRNA vaccines received a great thrust during the COVID-19 pandemic. Now, several mRNA-based HIV vaccines are undergoing clinical trials to evaluate their safety and efficacy. This review offers an overview of the pathogenesis and treatment of HIV / AIDS, previous efforts of HIV vaccine development and introduces mRNA vaccines as a promising and potential game changing platform for HIV vaccination.
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Affiliation(s)
- Andra Fortner
- Albert-Ludwigs-Universitat Freiburg, Germany,Victor Babes National Institute of Pathology, Bucharest, Romania
| | - Octavian Bucur
- Victor Babes National Institute of Pathology, Bucharest, Romania,Viron Molecular Medicine Institute, Boston, MA 02108, USA,* Corresponding authors: Octavian Bucur, MD, PhD, Next Generation Pathology Group, Victor Babes National Institute of Pathology, Bucharest, Romania and Viron Molecular Medicine Institute, Boston, MA 02108, USA; ;
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12
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Boutin M, Vézina D, Ding S, Prévost J, Laumaea A, Marchitto L, Anand SP, Medjahed H, Gendron-Lepage G, Bourassa C, Goyette G, Clark A, Richard J, Finzi A. Temsavir Treatment of HIV-1-Infected Cells Decreases Envelope Glycoprotein Recognition by Broadly Neutralizing Antibodies. mBio 2022;:e0057722. [PMID: 35475646 DOI: 10.1128/mbio.00577-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The heavily glycosylated HIV-1 envelope glycoprotein (Env) is the sole viral antigen present at the surface of virions and infected cells, representing the main target for antibody responses. The FDA-approved small molecule temsavir acts as an HIV-1 attachment inhibitor by preventing Env-CD4 interaction. This molecule also stabilizes Env in a prefusion "closed" conformation that is preferentially targeted by several broadly neutralizing antibodies (bNAbs). A recent study showed that an analog of temsavir (BMS-377806) affects the cleavage and addition of complex glycans on Env. In this study, we investigated the impact of temsavir on the overall glycosylation, proteolytic cleavage, cell surface expression, and antigenicity of Env. We found that temsavir impacts Env glycosylation and processing at physiological concentrations. This significantly alters the capacity of several bNAbs to recognize Env present on virions and HIV-1-infected cells. Temsavir treatment also reduces the capacity of bNAbs to eliminate HIV-1-infected cells by antibody-dependent cellular cytotoxicity (ADCC). Consequently, the impact of temsavir on Env glycosylation and antigenicity should be considered for the development of new antibody-based approaches in temsavir-treated individuals. IMPORTANCE FDA-approved fostemsavir, the prodrug for the active moiety small molecule temsavir (GSK 2616713 [formally BMS-626529]), acts as an attachment inhibitor by targeting the HIV-1 envelope (Env) and preventing CD4 interaction. Temsavir also stabilizes Env in its "closed," functional state 1 conformation, which represents an ideal target for broadly neutralizing antibodies (bNAbs). Since these antibodies recognize conformation-dependent epitopes composed of or adjacent to glycans, we evaluated the impact of temsavir treatment on overall Env glycosylation and its influence on bNAb recognition. Our results showed an alteration of Env glycosylation and cleavage by temsavir at physiological concentrations. This significantly modifies the overall antigenicity of Env and therefore reduces the capacity of bNAbs to recognize and eliminate HIV-1-infected cells by ADCC. These findings provide important information for the design of immunotherapies aimed at targeting the viral reservoir in temsavir-treated individuals.
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13
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Wagh K, van Gils MJ, Gristick H, Schommers P. Editorial: Novel Concepts in Using Broadly Neutralizing Antibodies for HIV-1 Treatment and Prevention. Front Immunol 2022; 12:823576. [PMID: 34992615 PMCID: PMC8724241 DOI: 10.3389/fimmu.2021.823576] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Accepted: 12/07/2021] [Indexed: 11/13/2022] Open
Affiliation(s)
- Kshitij Wagh
- Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, NM, United States
| | - Marit J van Gils
- Department of Medical Microbiology and Infection Prevention, Amsterdam Institute for Infection and Immunity, Amsterdam University Medical Centers (UMC), University of Amsterdam, Amsterdam, Netherlands
| | - Harry Gristick
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, United States
| | - Philipp Schommers
- Department of Internal Medicine, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.,German Center for Infection Research, Partner Site Bonn-Cologne, Cologne, Germany.,Laboratory of Experimental Immunology, Institute of Virology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
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14
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Siracusano G, Finardi A, Pastori C, Martinelli V, Furlan R, Lopalco L. HIV-1 Env Does Not Enable the Development of Protective Broadly Neutralizing Antibodies in an Experimental Autoimmune Encephalomyelitis Mouse Model. Front Immunol 2021; 12:771359. [PMID: 34795677 PMCID: PMC8593332 DOI: 10.3389/fimmu.2021.771359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Accepted: 10/14/2021] [Indexed: 12/03/2022] Open
Abstract
Recent studies showed that immunological tolerance may restrict the development of Env-specific autoreactive broadly neutralizing antibodies. This evidence is consistent with the finding that Env immunization of a systemic lupus erythematosus (SLE) murine model produced antibodies that neutralize tier 2 HIV-1 strains. In this study, we address the possibility of eliciting neutralizing anti-Env antibodies in other autoimmune diseases such as multiple sclerosis (MS). While, as reported for SLE, we showed for the first time that a small number of HIV-1 negative, relapsing remitting MS patients exhibited antibodies with neutralizing properties, our attempts at inducing those antibodies in a EAE mouse model of MS failed. The success in eliciting Env-specific neutralizing antibodies might be related to the specific characteristics of the autoimmune disease, or it might rely in improving the vaccination design. Studies using mouse models are useful to gain insight in how HIV-specific neutralizing antibody responses are regulated in order to develop a protective HIV-1 vaccine.
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Affiliation(s)
- Gabriel Siracusano
- Immunobiology of HIV, Division of Immunology, Transplantation and Infectious Diseases, San Raffaele Scientific Institute, Milan, Italy
| | - Annamaria Finardi
- Clinical Neuroimmunology Unit, Institute of Experimental Neurology (INSpe), Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
| | - Claudia Pastori
- Immunobiology of HIV, Division of Immunology, Transplantation and Infectious Diseases, San Raffaele Scientific Institute, Milan, Italy
| | | | - Roberto Furlan
- Clinical Neuroimmunology Unit, Institute of Experimental Neurology (INSpe), Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
| | - Lucia Lopalco
- Immunobiology of HIV, Division of Immunology, Transplantation and Infectious Diseases, San Raffaele Scientific Institute, Milan, Italy
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15
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Perera Molligoda Arachchige AS. NK cell-based therapies for HIV infection: Investigating current advances and future possibilities. J Leukoc Biol 2021; 111:921-931. [PMID: 34668588 DOI: 10.1002/jlb.5ru0821-412rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
NK cells are well-known for their antiviral functions. Also, their role in HIV has been well established, with rapid responses elicited during early HIV infection. Most immune cells including CD4+ T cells, monocytes, Mϕs, and dendritic cells are readily infected by HIV. Recent evidence from multiple studies has suggested that similar to these cells, in chronic conditions like HIV, NK cells also undergo functional exhaustion with impaired cytotoxicity, altered cytokine production, and impaired ADCC. NK-based immunotherapy aims to successfully restore, boost, and modify their activity as has been already demonstrated in the field of cancer immunotherapy. The utilization of NK cell-based strategies for the eradication of HIV from the body provides many advantages over classical ART. The literature search consisted of manually selecting the most relevant studies from databases including PubMed, Embase, Google Scholar, and ClinicalTrial.gov. Some of the treatments currently under consideration are CAR-NK cell therapy, facilitating ADCC, TLR agonists, bNAbs, and BiKEs/TriKEs, blocking inhibitory NK receptors during infection, IL-15 and IL-15 superagonists (eg: ALT-803), and so on. This review aims to discuss the NK cell-based therapies currently under experimentation against HIV infection and finally highlight the challenges associated with NK cell-based immunotherapies.
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16
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Moore CM, Grandits M, Grünwald-Gruber C, Altmann F, Kotouckova M, Teh AYH, Ma JKC. Characterisation of a highly potent and near pan-neutralising anti-HIV monoclonal antibody expressed in tobacco plants. Retrovirology 2021; 18:17. [PMID: 34183026 PMCID: PMC8240387 DOI: 10.1186/s12977-021-00560-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 06/09/2021] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND HIV remains one of the most important health issues worldwide, with almost 40 million people living with HIV. Although patients develop antibodies against the virus, its high mutation rate allows evasion of immune responses. Some patients, however, produce antibodies that are able to bind to, and neutralise different strains of HIV. One such 'broadly neutralising' antibody is 'N6'. Identified in 2016, N6 can neutralise 98% of HIV-1 isolates with a median IC50 of 0.066 µg/mL. This neutralisation breadth makes N6 a very promising therapeutic candidate. RESULTS N6 was expressed in a glycoengineered line of N. benthamiana plants (pN6) and compared to the mammalian cell-expressed equivalent (mN6). Expression at 49 mg/kg (fresh leaf tissue) was achieved in plants, although extraction and purification are more challenging than for most plant-expressed antibodies. N-glycoanalysis demonstrated the absence of xylosylation and a reduction in α(1,3)-fucosylation that are typically found in plant glycoproteins. The N6 light chain contains a potential N-glycosylation site, which was modified and displayed more α(1,3)-fucose than the heavy chain. The binding kinetics of pN6 and mN6, measured by surface plasmon resonance, were similar for HIV gp120. pN6 had a tenfold higher affinity for FcγRIIIa, which was reflected in an antibody-dependent cellular cytotoxicity assay, where pN6 induced a more potent response from effector cells than that of mN6. pN6 demonstrated the same potency and breadth of neutralisation as mN6, against a panel of HIV strains. CONCLUSIONS The successful expression of N6 in tobacco supports the prospect of developing a low-cost, low-tech production platform for a monoclonal antibody cocktail to control HIV in low-to middle income countries.
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Affiliation(s)
- Catherine M. Moore
- Hotung Molecular Immunology Unit, Institute for Infection & Immunity, St George’s University of London, Cranmer Terrace, London, SW17 0RE UK
| | - Melanie Grandits
- Hotung Molecular Immunology Unit, Institute for Infection & Immunity, St George’s University of London, Cranmer Terrace, London, SW17 0RE UK
| | - Clemens Grünwald-Gruber
- Department of Chemistry, University of Natural Resources and Applied Life Sciences, Vienna, Austria
| | - Friedrich Altmann
- Department of Chemistry, University of Natural Resources and Applied Life Sciences, Vienna, Austria
| | - Maria Kotouckova
- Hotung Molecular Immunology Unit, Institute for Infection & Immunity, St George’s University of London, Cranmer Terrace, London, SW17 0RE UK
| | - Audrey Y.-H. Teh
- Hotung Molecular Immunology Unit, Institute for Infection & Immunity, St George’s University of London, Cranmer Terrace, London, SW17 0RE UK
| | - Julian K.-C. Ma
- Hotung Molecular Immunology Unit, Institute for Infection & Immunity, St George’s University of London, Cranmer Terrace, London, SW17 0RE UK
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Abstract
INTRODUCTION Antiretroviral therapy (ART) has transformed prognoses for HIV-1-infected individuals but requires lifelong adherence to prevent viral resurgence. Targeted elimination or permanent deactivation of the latently infected reservoir harboring integrated proviral DNA, which drives viral rebound, is a major focus of HIV-1 research. AREAS COVERED This review covers the current approaches to developing curative strategies for HIV-1 that target the latent reservoir. Discussed herein are shock and kill, broadly neutralizing antibodies (bNAbs), block and lock, Chimeric antigen receptor (CAR) T cells, immune checkpoint modulation, clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) coreceptor ablation, and CRISPR/Cas9 proviral excision. Emphasis is placed on CRISPR/Cas9 proviral excision/inactivation. Recent advances and future directions toward discovery and translation of HIV-1 therapeutics are discussed. EXPERT OPINION CRISPR/Cas9 proviral targeting fills a niche amongst HIV-1 cure strategies by directly targeting the integrated provirus without the necessity of an innate or adaptive immune response. Each strategy discussed in this review has shown promising results with the potential to yield curative or adjuvant therapies. CRISPR/Cas9 is singular among these in that it addresses the root of the problem, integrated proviral DNA, with the capacity to permanently remove or deactivate the source of HIV-1 recrudescence.
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Affiliation(s)
- Andrew J. Atkins
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Alexander G. Allen
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Will Dampier
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19129, USA
| | - Elias K. Haddad
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Division of Infectious Diseases and HIV Medicine, Department of Medicine, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Michael R. Nonnemacher
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - Brian Wigdahl
- Department of Microbiology and Immunology, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Center for Molecular Virology and Translational Neuroscience, Institute for Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19129, USA,Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA 19107, USA,Correspondence should be addressed to B.W. (), 245 N 15th St, Rm 18301, MS1013A, Philadelphia, PA, 19102, Tel: 215-991-8352, Fax: 215-849-4808
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18
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Li W, Zhou Q, Xia L, Zou R, Zou W. Cellular and Immune Therapy for Treating HIV-1 Infection. AIDS Rev 2021; 23:59-64. [PMID: 33626034 DOI: 10.24875/aidsrev.20000110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
HIV-1 infection has caused a number of deaths worldwide and remains a global health concern. Combined antiretroviral therapy (cART) inhibits viral replication, prevents CD4+ T cell loss, and thus slows HIV disease progression. However, cART does not eradicate HIV-1. Infected individuals must remain on treatment for their entire lives and treatment interruption will result in viral rebound.
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Affiliation(s)
- Wei Li
- The First Clinical Medical College of Nanchang University, Jiangxi, Nanchang, China
| | - Qiqiang Zhou
- The First Clinical Medical College of Nanchang University, Jiangxi, Nanchang, China
| | - Lingbo Xia
- The First Clinical Medical College of Nanchang University, Jiangxi, Nanchang, China
| | - Ruixiang Zou
- The First Clinical Medical College of Nanchang University, Jiangxi, Nanchang, China
| | - Wei Zou
- Department of Infectious Diseases, the First Affiliated Hospital of Nanchang University. Nanchang, China
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Berendam SJ, Styles TM, Morgan-Asiedu PK, Tenney D, Kumar A, Obregon-Perko V, Bar KJ, Saunders KO, Santra S, De Paris K, Tomaras GD, Chahroudi A, Permar SR, Amara RR, Fouda GG. Systematic Assessment of Antiviral Potency, Breadth, and Synergy of Triple Broadly Neutralizing Antibody Combinations against Simian-Human Immunodeficiency Viruses. J Virol 2021; 95:e01667-20. [PMID: 33177194 DOI: 10.1128/JVI.01667-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 10/23/2020] [Indexed: 01/29/2023] Open
Abstract
Daily burden and clinical toxicities associated with antiretroviral therapy (ART) emphasize the need for alternative strategies to induce long-term human immunodeficiency virus (HIV) remission upon ART cessation. Broadly neutralizing antibodies (bNAbs) can both neutralize free virions and mediate effector functions against infected cells and therefore represent a leading immunotherapeutic approach. To increase potency and breadth, as well as to limit the development of resistant virus strains, it is likely that bNAbs will need to be administered in combination. It is therefore critical to identify bNAb combinations that can achieve robust polyfunctional antiviral activity against a high number of HIV strains. In this study, we systematically assessed the abilities of single bNAbs and triple bNAb combinations to mediate robust polyfunctional antiviral activity against a large panel of cross-clade simian-human immunodeficiency viruses (SHIVs), which are commonly used as tools for validation of therapeutic strategies targeting the HIV envelope in nonhuman primate models. We demonstrate that most bNAbs are capable of mediating both neutralizing and nonneutralizing effector functions against cross-clade SHIVs, although the susceptibility to V3 glycan-specific bNAbs is highly strain dependent. Moreover, we observe a strong correlation between the neutralization potencies and nonneutralizing effector functions of bNAbs against the transmitted/founder SHIV CH505. Finally, we identify several triple bNAb combinations comprising of CD4 binding site-, V2-glycan-, and gp120-gp41 interface-targeting bNAbs that are capable of mediating synergistic polyfunctional antiviral activities against multiple clade A, B, C, and D SHIVs.IMPORTANCE Optimal bNAb immunotherapeutics will need to mediate multiple antiviral functions against a broad range of HIV strains. Our systematic assessment of triple bNAb combinations against SHIVs will identify bNAbs with synergistic, polyfunctional antiviral activity that will inform the selection of candidate bNAbs for optimal combination designs. The identified combinations can be validated in vivo in future passive immunization studies using the SHIV challenge model.
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Khurana S, Hahn M, Klenow L, Golding H. Autoreactivity of Broadly Neutralizing Influenza Human Antibodies to Human Tissues and Human Proteins. Viruses 2020; 12:v12101140. [PMID: 33049994 PMCID: PMC7600923 DOI: 10.3390/v12101140] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 09/24/2020] [Accepted: 09/26/2020] [Indexed: 01/11/2023] Open
Abstract
Broadly neutralizing monoclonal antibodies (bNAbs) against conserved domains in the influenza hemagglutinin are in clinical trials. Several next generation influenza vaccines designed to elicit such bNAbs are also in clinical development. One of the common features of the isolated bNAbs is the use of restricted IgVH repertoire. More than 80% of stem-targeting bNAbs express IgVH1-69, which may indicate genetic constraints on the evolution of such antibodies. In the current study, we evaluated a panel of influenza virus bNAbs in comparison with HIV-1 MAb 4E10 and anti-RSV MAb Palivizumab (approved for human use) for autoreactivity using 30 normal human tissues microarray and human protein (>9000) arrays. We found that several human bNAbs (CR6261, CR9114, and F2603) reacted with human tissues, especially with pituitary gland tissue. Importantly, protein array analysis identified high-affinity interaction of CR6261 with the autoantigen “Enhancer of mRNA decapping 3 homolog” (EDC3), which was not previously described. Moreover, EDC3 competed with hemagglutinin for binding to bNAb CR6261. These autoreactivity findings underscores the need for careful evaluation of such bNAbs for therapeutics and stem-based vaccines against influenza virus.
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Suphaphiphat K, Tolazzi M, Hua S, Desjardins D, Lorin V, Dereuddre-Bosquet N, Mouquet H, Scarlatti G, Grand RL, Cavarelli M. Broadly neutralizing antibodies potently inhibit cell-to-cell transmission of semen leukocyte-derived SHIV162P3. EBioMedicine 2020; 57:102842. [PMID: 32619962 PMCID: PMC7334370 DOI: 10.1016/j.ebiom.2020.102842] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 05/24/2020] [Accepted: 06/02/2020] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND HIV-1 sexual transmission occurs mostly through infected semen, which contains both free virions and infected leukocytes. Transmission initiated by infected cells has been shown by several in vitro and in vivo studies and a reduced capacity of broadly neutralizing antibodies (bNAbs) to inhibit cell-to-cell transmission has also been reported. However, due to limitations of available experimental models, there is yet no clarity to which extend bNAbs can prevent transmission mediated by semen leukocytes. METHODS We developed a novel in vitro assay to measure cell-cell transmission that makes use of splenocytes or CD45+ semen leukocytes collected from acutely SHIV162P3-infected cynomolgus macaques. A panel of 11 bNAbs was used either alone or in combination to assess their inhibitory potential against both cell-free and cell-cell infection. FINDINGS Splenocytes and semen leucocytes displayed a similar proportion of CD4+T-cell subsets. Either cell type transferred infection in vitro to target TZM-bl cells and PBMCs. Moreover, infection of macaques was achieved following intravaginal challenge with splenocytes. The anti-N-glycans/V3 loop bNAb 10-1074 was highly efficient against cell-associated transmission mediated by infected spleen cells and its potency was maintained when transmission was mediated by CD45+ semen leukocytes. INTERPRETATION These results support the use of bNAbs in preventative or therapeutic studies aiming to block transmission events mediated not only by free viral particles but also by infected cells. Our experimental system could be used to predict in vivo efficacy of bNAbs. FUNDING This work was funded by the ANRS and the European Commission.
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Affiliation(s)
- Karunasinee Suphaphiphat
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Auto-immune, Hematological and Bacterial diseases ≫ (IMVA-HB/IDMIT), Fontenay-aux-Roses & Le Kremlin-Bicêtre, France
| | - Monica Tolazzi
- Viral Evolution and Transmission Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Stéphane Hua
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Auto-immune, Hematological and Bacterial diseases ≫ (IMVA-HB/IDMIT), Fontenay-aux-Roses & Le Kremlin-Bicêtre, France
| | - Delphine Desjardins
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Auto-immune, Hematological and Bacterial diseases ≫ (IMVA-HB/IDMIT), Fontenay-aux-Roses & Le Kremlin-Bicêtre, France
| | - Valerie Lorin
- Laboratory of Humoral Immunology, Department of Immunology, Institut Pasteur, INSERM U1222, Paris, France
| | - Nathalie Dereuddre-Bosquet
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Auto-immune, Hematological and Bacterial diseases ≫ (IMVA-HB/IDMIT), Fontenay-aux-Roses & Le Kremlin-Bicêtre, France
| | - Hugo Mouquet
- Laboratory of Humoral Immunology, Department of Immunology, Institut Pasteur, INSERM U1222, Paris, France
| | - Gabriella Scarlatti
- Viral Evolution and Transmission Unit, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Roger Le Grand
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Auto-immune, Hematological and Bacterial diseases ≫ (IMVA-HB/IDMIT), Fontenay-aux-Roses & Le Kremlin-Bicêtre, France
| | - Mariangela Cavarelli
- Université Paris-Saclay, Inserm, CEA, Center for Immunology of Viral, Auto-immune, Hematological and Bacterial diseases ≫ (IMVA-HB/IDMIT), Fontenay-aux-Roses & Le Kremlin-Bicêtre, France.
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22
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Wang Q, Finzi A, Sodroski J. The Conformational States of the HIV-1 Envelope Glycoproteins. Trends Microbiol 2020; 28:655-67. [PMID: 32418859 DOI: 10.1016/j.tim.2020.03.007] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Accepted: 03/25/2020] [Indexed: 12/16/2022]
Abstract
During HIV-1 entry into target cells, binding of the virus to host receptors, CD4 and CCR5/CXCR4, triggers serial conformational changes in the envelope glycoprotein (Env) trimer that result in the fusion of the viral and cell membranes. Recent discoveries have refined our knowledge of Env conformational states, allowing characterization of the targets of small-molecule HIV-1 entry inhibitors and neutralizing antibodies, and identifying a novel off-pathway conformation (State 2A). Here, we provide an overview of the current understanding of these conformational states, focusing on (i) the events during HIV-1 entry; (ii) conformational preferences of HIV-1 Env ligands; (iii) evasion of the host antibody response; and (iv) potential implications for therapy and prevention of HIV-1 infection.
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23
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Martinez DR, Tu JJ, Kumar A, Mangold JF, Mangan RJ, Goswami R, Giorgi EE, Chen J, Mengual M, Douglas AO, Heimsath H, Saunders KO, Nicely NI, Eudailey J, Hernandez G, Morgan-Asiedu PK, Wiehe K, Haynes BF, Moody MA, LaBranche C, Montefiori DC, Gao F, Permar SR. Maternal Broadly Neutralizing Antibodies Can Select for Neutralization-Resistant, Infant-Transmitted/Founder HIV Variants. mBio 2020; 11:e00176-20. [PMID: 32156815 PMCID: PMC7064758 DOI: 10.1128/mbio.00176-20] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 01/31/2020] [Indexed: 01/21/2023] Open
Abstract
Each year, >180,000 infants become infected via mother-to-child transmission (MTCT) of HIV despite the availability of effective maternal antiretroviral treatments, underlining the need for a maternal HIV vaccine. We characterized 224 maternal HIV envelope (Env)-specific IgG monoclonal antibodies (MAbs) from seven nontransmitting and transmitting HIV-infected U.S. and Malawian mothers and examined their neutralization activities against nontransmitted autologous circulating viruses and infant-transmitted founder (infant-T/F) viruses. Only a small subset of maternal viruses, 3 of 72 (4%), were weakly neutralized by maternal linear V3 epitope-specific IgG MAbs, whereas 6 out of 6 (100%) infant-T/F viruses were neutralization resistant to these V3-specific IgG MAbs. We also show that maternal-plasma broadly neutralizing antibody (bNAb) responses targeting the V3 glycan supersite in a transmitting woman may have selected for an N332 V3 glycan neutralization-resistant infant-T/F virus. These data have important implications for bNAb-eliciting vaccines and passively administered bNAbs in the setting of MTCT.IMPORTANCE Efforts to eliminate MTCT of HIV with antiretroviral therapy (ART) have met little success, with >180,000 infant infections each year worldwide. It is therefore likely that additional immunologic strategies that can synergize with ART will be required to eliminate MTCT of HIV. To this end, understanding the role of maternal HIV Env-specific IgG antibodies in the setting of MTCT is crucial. In this study, we found that maternal-plasma broadly neutralizing antibody (bNAb) responses can select for T/F viruses that initiate infection in infants. We propose that clinical trials testing the efficacy of single bNAb specificities should not include HIV-infected pregnant women, as a single bNAb might select for neutralization-resistant infant-T/F viruses.
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Affiliation(s)
- David R Martinez
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
- Duke Human Vaccine Institute, Durham, North Carolina, USA
| | - Joshua J Tu
- Duke Human Vaccine Institute, Durham, North Carolina, USA
| | - Amit Kumar
- Duke Human Vaccine Institute, Durham, North Carolina, USA
| | | | - Riley J Mangan
- Duke Human Vaccine Institute, Durham, North Carolina, USA
| | - Ria Goswami
- Duke Human Vaccine Institute, Durham, North Carolina, USA
| | - Elena E Giorgi
- Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Juilin Chen
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
- Duke Human Vaccine Institute, Durham, North Carolina, USA
| | - Michael Mengual
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | | | - Holly Heimsath
- Duke Human Vaccine Institute, Durham, North Carolina, USA
| | - Kevin O Saunders
- Duke Human Vaccine Institute, Durham, North Carolina, USA
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | | | | | | | | | - Kevin Wiehe
- Duke Human Vaccine Institute, Durham, North Carolina, USA
| | - Barton F Haynes
- Duke Human Vaccine Institute, Durham, North Carolina, USA
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - M Anthony Moody
- Duke Human Vaccine Institute, Durham, North Carolina, USA
- Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
| | - Celia LaBranche
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - David C Montefiori
- Duke Human Vaccine Institute, Durham, North Carolina, USA
- Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Feng Gao
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA
| | - Sallie R Permar
- Department of Molecular Genetics and Microbiology, Duke University Medical Center, Durham, North Carolina, USA
- Duke Human Vaccine Institute, Durham, North Carolina, USA
- Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, USA
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24
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Dubrovskaya V, Tran K, Ozorowski G, Guenaga J, Wilson R, Bale S, Cottrell CA, Turner HL, Seabright G, O'Dell S, Torres JL, Yang L, Feng Y, Leaman DP, Vázquez Bernat N, Liban T, Louder M, McKee K, Bailer RT, Movsesyan A, Doria-Rose NA, Pancera M, Karlsson Hedestam GB, Zwick MB, Crispin M, Mascola JR, Ward AB, Wyatt RT. Vaccination with Glycan-Modified HIV NFL Envelope Trimer-Liposomes Elicits Broadly Neutralizing Antibodies to Multiple Sites of Vulnerability. Immunity 2019; 51:915-929.e7. [PMID: 31732167 PMCID: PMC6891888 DOI: 10.1016/j.immuni.2019.10.008] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 10/04/2019] [Accepted: 10/22/2019] [Indexed: 01/31/2023]
Abstract
The elicitation of broadly neutralizing antibodies (bNAbs) against the HIV-1 envelope glycoprotein (Env) trimer remains a major vaccine challenge. Most cross-conserved protein determinants are occluded by self-N-glycan shielding, limiting B cell recognition of the underlying polypeptide surface. The exceptions to the contiguous glycan shield include the conserved receptor CD4 binding site (CD4bs) and glycoprotein (gp)41 elements proximal to the furin cleavage site. Accordingly, we performed heterologous trimer-liposome prime:boosting in rabbits to drive B cells specific for cross-conserved sites. To preferentially expose the CD4bs to B cells, we eliminated proximal N-glycans while maintaining the native-like state of the cleavage-independent NFL trimers, followed by gradual N-glycan restoration coupled with heterologous boosting. This approach successfully elicited CD4bs-directed, cross-neutralizing Abs, including one targeting a unique glycan-protein epitope and a bNAb (87% breadth) directed to the gp120:gp41 interface, both resolved by high-resolution cryoelectron microscopy. This study provides proof-of-principle immunogenicity toward eliciting bNAbs by vaccination.
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Affiliation(s)
- Viktoriya Dubrovskaya
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Karen Tran
- International AIDS Vaccine Initiative, Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Gabriel Ozorowski
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Javier Guenaga
- International AIDS Vaccine Initiative, Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Richard Wilson
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Shridhar Bale
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Christopher A Cottrell
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Hannah L Turner
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Gemma Seabright
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - Sijy O'Dell
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Jonathan L Torres
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Lifei Yang
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Yu Feng
- International AIDS Vaccine Initiative, Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Daniel P Leaman
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Néstor Vázquez Bernat
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm 171 77, Sweden
| | - Tyler Liban
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Mark Louder
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Krisha McKee
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Robert T Bailer
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Arlette Movsesyan
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Nicole A Doria-Rose
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Marie Pancera
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | | | - Michael B Zwick
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Max Crispin
- School of Biological Sciences, University of Southampton, Southampton, UK
| | - John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD 20892, USA
| | - Andrew B Ward
- International AIDS Vaccine Initiative, Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Richard T Wyatt
- Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA; International AIDS Vaccine Initiative, Neutralizing Antibody Center at The Scripps Research Institute, La Jolla, CA 92037, USA; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, CA 92037, USA.
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25
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Shacklett BL, Blanco J, Hightow-Weidman L, Mgodi N, Alcamí J, Buchbinder S, Chirenje M, Dabee S, Diallo M, Dumchev K, Herrera C, Levy ME, Martin Gayo E, Makoah NA, Mitchell KM, Mugwanya K, Reddy K, Rodríguez ML, Rodriguez-Garcia M, Shover CL, Shrivastava T, Tomaras G, Van Diepen M, Walia M, Warren M, Manrique A, Thyagarajan B, Torri T. HIV Research for Prevention 2018: From Research to Impact Conference Summary and Highlights. AIDS Res Hum Retroviruses 2019; 35:598-607. [PMID: 31007035 PMCID: PMC6602109 DOI: 10.1089/aid.2019.0074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
The HIV Research for Prevention (HIVR4P) conference is dedicated to advancing HIV prevention research, responding to a growing consensus that effective and durable prevention will require a combination of approaches as well as unprecedented collaboration among scientists, practitioners, and community workers from different fields and geographic areas. The conference theme in 2018, "From Research to Impact," acknowledged an increasing focus on translation of promising research findings into practical, accessible, and affordable HIV prevention options for those who need them worldwide. HIVR4P 2018 was held in Madrid, Spain, on 21-25 October, with >1,400 participants from 52 countries around the globe, representing all aspects of HIV prevention research and implementation. The program included 137 oral and 610 poster presentations. This article presents a brief summary of highlights from the conference. More detailed information, complete abstracts as well as webcasts and daily Rapporteur summaries may be found on the conference website.
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Affiliation(s)
- Barbara L. Shacklett
- Medical Microbiology and Immunology, University of California, Davis, Davis, California
| | - Julià Blanco
- IrsiCaixa, IGTP, Barcelona, Spain
- Chair in AIDS and Related Illnesses, Centre for Health and Social Care Research (CESS), Faculty of Medicine, University of Vic-UCC, Barcelona, Spain
| | - Lisa Hightow-Weidman
- Division of Infectious Diseases, University of North Carolina, Chapel Hill, Chapel Hill, North Carolina
| | - Nyaradzo Mgodi
- University of Zimbabwe College of Health Sciences, Harare, Zimbabwe
| | - José Alcamí
- AIDS Immunopathology Unit, Instituto de Salud Carlos III, Madrid, Spain
| | - Susan Buchbinder
- San Francisco Department of Public Health, San Francisco, California
| | - Mike Chirenje
- University of Zimbabwe College of Health Sciences, Harare, Zimbabwe
| | - Smritee Dabee
- Division of Medical Virology, University of Cape Town, Cape Town, South Africa
| | - Mamadou Diallo
- Department of Social and Preventive Medicine, University Laval, Quebec, Canada
| | | | - Carolina Herrera
- Faculty of Medicine, Department of Medicine, Imperial College London, London, United Kingdom
| | - Matthew E. Levy
- Department of Epidemiology and Biostatistics, The George Washington University, Washington, District of Columbia
| | - Enrique Martin Gayo
- Immunology Department, Hospital Universitario La Princesa, Universidad Autónoma de Madrid, Madrid, Spain
| | - Nigel Aminake Makoah
- Centre for HIV and STIs, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Kate M. Mitchell
- MRC Centre for Global Infectious Disease Analysis, Imperial College London, London, United Kingdom
- HPTN Modelling Centre, Imperial College London, London, United Kingdom
| | - Kenneth Mugwanya
- Department of Epidemiology, University of Washington, Seattle, Washington
| | - Krishnaveni Reddy
- Wits Reproductive Health and HIV Institute, University of the Witwatersrand, School of Clinical Medicine, Johannesburg, South Africa
| | | | - Marta Rodriguez-Garcia
- Department of Physiology and Neurobiology, Geisel School of Medicine at Dartmouth, Lebanon, New Hampshire
| | - Chelsea L. Shover
- Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, California
| | - Tripti Shrivastava
- Department of Infection and Immunology, Translational Health Science and Technology Institute, Faridabad, India
| | - Georgia Tomaras
- Departments of Surgery, Immunology, and Molecular Genetics and Microbiology, Duke University, Durham, North Carolina
| | - Michiel Van Diepen
- Division of Medical Virology, University of Cape Town, Cape Town, South Africa
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26
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Rudometov AP, Rudometova NB, Shcherbakov DN, Lomzov AA, Kaplina ON, Shcherbakova NS, Ilyichev AA, Bakulina AY, Karpenko LI. The Structural and Immunological Properties of Chimeric Proteins Containing HIV-1 MPER Sites. Acta Naturae 2019; 11:56-65. [PMID: 31720017 PMCID: PMC6826149 DOI: 10.32607/20758251-2019-11-3-56-65] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 08/07/2019] [Indexed: 11/20/2022] Open
Abstract
The human immunodeficiency virus (HIV-1) poses a serious risk to global public health. The development of a safe and effective vaccine could stop the HIV/AIDS pandemic. Much of the research focused on HIV-1 prevention through vaccination is aimed at developing immunogens and immunization strategies to induce the formation of antibodies with neutralizing activity against a broad range of HIV-1 isolates (bNAbs). The objective of this study was to develop immunogens capable of targeting an immune response to MPER, one of the regions of bNAb binding in Env. Two immunogens carrying MPER fragments on their scaffolds (protein YkuJ Bacillus subtilis and artificial polypeptide TBI) were constructed. Circular dichroism spectroscopy was used to show that the secondary structure of the immunogens was consistent with their theoretical models. The antigenic structure of the MPER-TBI and YkuJ-MPER proteins was characterized using bNAbs that recognize HIV-1 MPER (2F5, 4E10, and 10E8). The rabbit model made it possible to show the immunogenicity of the constructed recombinant proteins. The resulting serum was found to be cross-reactive with immunogens carrying MPER. The constructs designed and characterized in this study can be used for targeting the humoral immune response to MPER, which is known to be one of the sites of HIV-1 vulnerability.
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Affiliation(s)
- A. P. Rudometov
- State Research Center of Virology and Biotechnology “Vector”, Koltsovo, Novosibirsk region, 630559 , Russia
| | - N. B. Rudometova
- State Research Center of Virology and Biotechnology “Vector”, Koltsovo, Novosibirsk region, 630559 , Russia
| | - D. N. Shcherbakov
- State Research Center of Virology and Biotechnology “Vector”, Koltsovo, Novosibirsk region, 630559 , Russia
- Altai State University, Lenin Ave. 61, Barnaul, 656049, Russia
| | - A. A. Lomzov
- Institute of Chemical Biology and Fundamental Medicine SB RAS, Ac. Lavrentieva Ave. 8, Novosibirsk, 630090, Russia
- Novosibirsk State University, Pirogova Str. 1, Novosibirsk, 630090, Russia
| | - O. N. Kaplina
- State Research Center of Virology and Biotechnology “Vector”, Koltsovo, Novosibirsk region, 630559 , Russia
| | - N. S. Shcherbakova
- State Research Center of Virology and Biotechnology “Vector”, Koltsovo, Novosibirsk region, 630559 , Russia
| | - A. A. Ilyichev
- State Research Center of Virology and Biotechnology “Vector”, Koltsovo, Novosibirsk region, 630559 , Russia
| | - A. Yu. Bakulina
- State Research Center of Virology and Biotechnology “Vector”, Koltsovo, Novosibirsk region, 630559 , Russia
- Novosibirsk State University, Pirogova Str. 1, Novosibirsk, 630090, Russia
| | - L. I. Karpenko
- State Research Center of Virology and Biotechnology “Vector”, Koltsovo, Novosibirsk region, 630559 , Russia
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27
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Anand SP, Grover JR, Tolbert WD, Prévost J, Richard J, Ding S, Baril S, Medjahed H, Evans DT, Pazgier M, Mothes W, Finzi A. Antibody-Induced Internalization of HIV-1 Env Proteins Limits Surface Expression of the Closed Conformation of Env. J Virol 2019; 93:e00293-19. [PMID: 30894474 PMCID: PMC6532100 DOI: 10.1128/jvi.00293-19] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 03/16/2019] [Indexed: 01/10/2023] Open
Abstract
To minimize immune responses against infected cells, HIV-1 limits the surface expression of its envelope glycoprotein (Env). Here, we demonstrate that this mechanism is specific for the Env conformation and affects the efficiency of antibody-dependent cellular cytotoxicity (ADCC). Using flow cytometry and confocal microscopy, we show that broadly neutralizing antibodies (bNAbs) targeting the "closed" conformation of Env induce its internalization from the surface. In contrast, non-neutralizing antibodies (nNAbs) are displayed on the cell surface for prolonged period of times. The bNAb-induced Env internalization can be decreased by blocking dynamin function, which translates into higher susceptibilities of infected cells to ADCC. Our results suggest that antibody-mediated Env internalization is a mechanism used by HIV-1 to evade immune responses against the "closed" conformation of Env expressed on HIV-1-infected cells.IMPORTANCE HIV-1 has evolved to acquire several strategies to limit the exposure of its envelope glycoproteins (Env) on the surface of infected cells. In this study, we show that antibody-induced Env internalization is conformation specific and reduces the susceptibility of infected cells to antibody-dependent cellular cytotoxicity (ADCC). Thus, a better understanding of this mechanism might help develop antibodies with improved capacities to mediate ADCC.
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Affiliation(s)
- Sai Priya Anand
- Centre de Recherche du CHUM, Montreal, Quebec, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
| | - Jonathan R Grover
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, USA
| | - William D Tolbert
- Infectious Diseases Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Jérémie Prévost
- Centre de Recherche du CHUM, Montreal, Quebec, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Quebec, Canada
| | | | - Shilei Ding
- Centre de Recherche du CHUM, Montreal, Quebec, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Quebec, Canada
| | - Sophie Baril
- Centre de Recherche du CHUM, Montreal, Quebec, Canada
| | | | - David T Evans
- Department of Pathology and Laboratory Medicine, University of Wisconsin, Madison, Wisconsin, USA
- Wisconsin National Primate Research Center, University of Wisconsin, Madison, Wisconsin, USA
| | - Marzena Pazgier
- Infectious Diseases Division, Department of Medicine of Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Walther Mothes
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Andrés Finzi
- Centre de Recherche du CHUM, Montreal, Quebec, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montreal, Quebec, Canada
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Dashti A, DeVico AL, Lewis GK, Sajadi MM. Broadly Neutralizing Antibodies against HIV: Back to Blood. Trends Mol Med 2019; 25:228-240. [PMID: 30792120 DOI: 10.1016/j.molmed.2019.01.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 01/15/2019] [Accepted: 01/15/2019] [Indexed: 12/26/2022]
Abstract
After years of continuous exposure to HIV envelope antigens, a minority of HIV-infected individuals develop a cognate polyclonal humoral response comprising very potent and extremely cross-reactive neutralizing antibodies [broadly neutralizing antibodies (bNAbs)]. Isolated bNAbs derived from memory B cell pools have been the focus of intense studies over the past decade. However, it is not yet known how to translate the features of bNAbs into practical HIV prevention methods. In this review, we attempt to seek insights from emerging information about the human broadly neutralizing plasma response as well as its frequency, clonal composition, specificity, potency, and commonality among infected subjects. We also consider how this information points to selecting and prioritizing certain epitope targets and strategies for HIV vaccine design.
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Affiliation(s)
- Amir Dashti
- Divisions of Vaccine Research and Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Anthony L DeVico
- Divisions of Vaccine Research and Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - George K Lewis
- Divisions of Vaccine Research and Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Mohammad M Sajadi
- Divisions of Vaccine Research and Clinical Care and Research, Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201, USA; Department of Medicine, Baltimore VA Medical Center, Baltimore, MD 21201, USA.
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Zhang Y, Chapman JH, Ulcay A, Sutton RE. Neutralization Synergy between HIV-1 Attachment Inhibitor Fostemsavir and Anti-CD4 Binding Site Broadly Neutralizing Antibodies against HIV. J Virol 2019; 93:e01446-18. [PMID: 30518644 DOI: 10.1128/JVI.01446-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/20/2018] [Indexed: 02/08/2023] Open
Abstract
Attachment inhibitor (AI) BMS-626529 (fostemsavir) represents a novel class of antiretrovirals which target human immunodeficiency virus type 1 (HIV-1) gp120 and block CD4-induced conformational changes required for viral entry. It is now in phase III clinical trials and is expected to be approved by the U.S. Food and Drug Administration (FDA) in the near future. Although fostemsavir is very potent against HIV in vitro and in vivo, a number of resistant mutants have already been identified. Broadly neutralizing HIV antibodies (bNAbs) can potently inhibit a wide range of HIV-1 strains by binding to viral Env and are very promising candidates for HIV-1 prevention and therapy. Since both target viral Env to block viral entry, we decided to investigate the relationship between these two inhibitors. Our data show that Env mutants resistant to BMS-626529 retained susceptibility to bNAbs. A single treatment of bNAb NIH45-46G54W completely inhibited the replication of these escape mutants. Remarkable synergy was observed between BMS-626529 and CD4 binding site (CD4bs)-targeting bNAbs in neutralizing HIV-1 strains at low concentrations. This synergistic effect was enhanced against virus harboring mutations conferring resistance to BMS-626529. The mechanistic basis of the observed synergy is likely enhanced inhibition of CD4 binding to the HIV-1 Env trimer by the combination of BMS-626529 and CD4bs-targeting bNAbs. This work highlights the potential for positive interplay between small- and large-molecule therapeutics against HIV entry, which may prove useful as these agents enter clinical use.IMPORTANCE As the worldwide HIV pandemic continues, there is a continued need for novel drugs and therapies. A new class of drug, the attachment inhibitors, will soon be approved for the treatment of HIV. Broadly neutralizing antibodies are also promising candidates for HIV prevention and therapy. We investigated how this drug might work with these exciting antibodies that are very potent in blocking HIV infection of cells. These antibodies worked against virus known to be resistant to the new drug. In addition, a specific type of antibody worked really well with the new drug in blocking virus infection of cells. This work has implications for both the new drug and the antibodies that are poised to be used against HIV.
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Gardner MR, Fetzer I, Kattenhorn LM, Davis-Gardner ME, Zhou AS, Alfant B, Weber JA, Kondur HR, Martinez-Navio JM, Fuchs SP, Desrosiers RC, Gao G, Lifson JD, Farzan M. Anti-drug Antibody Responses Impair Prophylaxis Mediated by AAV-Delivered HIV-1 Broadly Neutralizing Antibodies. Mol Ther 2019; 27:650-660. [PMID: 30704961 PMCID: PMC6403482 DOI: 10.1016/j.ymthe.2019.01.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 01/04/2019] [Accepted: 01/08/2019] [Indexed: 11/12/2022] Open
Abstract
Adeno-associated virus (AAV) delivery of potent and broadly neutralizing antibodies (bNAbs is a promising approach for the prevention of HIV-1 infection. The immunoglobulin G (IgG)1 subtype is usually selected for this application, because it efficiently mediates antibody effector functions and has a somewhat longer half-life. However, the use of IgG1-Fc has been associated with the generation of anti-drug antibodies (ADAs) that correlate with loss of antibody expression. In contrast, we have shown that expression of the antibody-like molecule eCD4-Ig bearing a rhesus IgG2-Fc domain showed reduced immunogenicity and completely protected rhesus macaques from simian-HIV (SHIV)-AD8 challenges. To directly compare the performance of the IgG1-Fc and the IgG2-Fc domains in a prophylactic setting, we compared AAV1 expression of rhesus IgG1 and IgG2 forms of four anti-HIV bNAbs: 3BNC117, NIH45-46, 10-1074, and PGT121. Interestingly, IgG2-isotyped bNAbs elicited significantly lower ADA than their IgG1 counterparts. We also observed significant protection from two SHIV-AD8 challenges in macaques expressing IgG2-isotyped bNAbs, but not from those expressing IgG1. Our data suggest that monoclonal antibodies isotyped with IgG2-Fc domains are less immunogenic than their IgG1 counterparts, and they highlight ADAs as a key barrier to the use of AAV1-expressed bNAbs.
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Affiliation(s)
- Matthew R Gardner
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL 33458, USA.
| | - Ina Fetzer
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Lisa M Kattenhorn
- Department of Microbiology and Immunobiology, Harvard Medical School, New England Primate Research Center, Southborough, MA 01772, USA
| | - Meredith E Davis-Gardner
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Amber S Zhou
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Barnett Alfant
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Jesse A Weber
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Hema R Kondur
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL 33458, USA
| | - Jose M Martinez-Navio
- Department of Pathology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Sebastian P Fuchs
- Department of Pathology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Ronald C Desrosiers
- Department of Pathology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
| | - Guangping Gao
- The Horae Gene Therapy Center, University of Massachusetts Medical School, Worcester, MA 01605, USA; Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, Frederick, MD 21702, USA
| | - Michael Farzan
- Department of Immunology and Microbiology, The Scripps Research Institute, Jupiter, FL 33458, USA
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Ditse Z, Muenchhoff M, Adland E, Jooste P, Goulder P, Moore PL, Morris L. HIV-1 Subtype C-Infected Children with Exceptional Neutralization Breadth Exhibit Polyclonal Responses Targeting Known Epitopes. J Virol 2018; 92:e00878-18. [PMID: 29950423 DOI: 10.1128/JVI.00878-18] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 06/14/2018] [Indexed: 02/01/2023] Open
Abstract
An HIV vaccine is likely to require bNAbs, which have been shown to prevent HIV acquisition in nonhuman primates. Recent evidence suggests that HIV-infected children are inherently better at generating bNAbs than adults. Here, we show that exceptional neutralization breadth in a group of viremic HIV-1 subtype C-infected children was due to the presence of polyclonal bNAb responses. These bNAbs targeted multiple epitopes on the HIV envelope glycoprotein previously defined in adult infection, suggesting that the immature immune system recognizes HIV antigens similarly. Since elicitation of a polyclonal bNAb response is the basis of next-generation HIV envelope vaccines, further studies of how bNAb lineages are stimulated in children is warranted. Furthermore, our findings suggest that children may respond particularly well to vaccines designed to elicit antibodies to multiple bNAb epitopes. We have previously shown that HIV-1-infected children develop broader and more potent neutralizing antibody responses than adults. This study aimed to determine the antibody specificities in 16 HIV-1 subtype C-infected children who displayed exceptional neutralization breadth on a 22-multisubtype virus panel. All children were antiretroviral treatment (ART) naive with normal CD4 counts despite being infected for a median of 10.1 years with high viral loads. The specificity of broadly neutralizing antibodies (bNAbs) was determined using epitope-ablating mutants, chimeric constructs, and depletion or inhibition of activity with peptides and glycoproteins. We found that bNAbs in children largely targeted previously defined epitopes, including the V2-glycan, V3-glycan, CD4bs, and gp120-gp41 interface. Remarkably, 63% of children had antibodies targeting 2 or 3 and, in one case, 4 of these bNAb epitopes. Longitudinal analysis of plasma from a mother-child pair over 9 years showed that while they both had similar neutralization profiles, the antibody specificities differed. The mother developed antibodies targeting the V2-glycan and CD4bs, whereas bNAb specificities in the child could not be mapped until 6 years, when a minor V2-glycan response appeared. The child also developed high-titer membrane-proximal external region (MPER) binding antibodies not seen in the mother, although these were not a major bNAb specificity. Overall, exceptional neutralization breadth in this group of children may be the result of extended exposure to high antigenic load in the context of an intact immune system, which allowed for the activation of multiple B cell lineages and the generation of polyclonal responses targeting several bNAb epitopes. IMPORTANCE An HIV vaccine is likely to require bNAbs, which have been shown to prevent HIV acquisition in nonhuman primates. Recent evidence suggests that HIV-infected children are inherently better at generating bNAbs than adults. Here, we show that exceptional neutralization breadth in a group of viremic HIV-1 subtype C-infected children was due to the presence of polyclonal bNAb responses. These bNAbs targeted multiple epitopes on the HIV envelope glycoprotein previously defined in adult infection, suggesting that the immature immune system recognizes HIV antigens similarly. Since elicitation of a polyclonal bNAb response is the basis of next-generation HIV envelope vaccines, further studies of how bNAb lineages are stimulated in children is warranted. Furthermore, our findings suggest that children may respond particularly well to vaccines designed to elicit antibodies to multiple bNAb epitopes.
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Stadtmueller BM, Bridges MD, Dam KM, Lerch MT, Huey-Tubman KE, Hubbell WL, Bjorkman PJ. DEER Spectroscopy Measurements Reveal Multiple Conformations of HIV-1 SOSIP Envelopes that Show Similarities with Envelopes on Native Virions. Immunity 2018; 49:235-246.e4. [PMID: 30076100 PMCID: PMC6104740 DOI: 10.1016/j.immuni.2018.06.017] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Revised: 05/15/2018] [Accepted: 06/28/2018] [Indexed: 12/31/2022]
Abstract
HIV-1 Envelope (Env) mediates viral-host membrane fusion after binding host-receptor CD4 and coreceptor. Soluble envelopes (SOSIPs), designed to mimic prefusion conformational states of virion-bound envelopes, are proposed immunogens for eliciting neutralizing antibodies, yet only static structures are available. To evaluate conformational landscapes of ligand-free, CD4-bound, inhibitor-bound, and antibody-bound SOSIPs, we measured inter-subunit distances throughout spin-labeled SOSIPs using double electron-electron resonance (DEER) spectroscopy and compared results to soluble and virion-bound Env structures, and single-molecule fluorescence resonance energy transfer (smFRET)-derived dynamics of virion-bound Envs. Unliganded SOSIP measurements were consistent with closed, neutralizing antibody-bound structures and shielding of non-neutralizing epitopes, demonstrating homogeneity at Env apex, increased flexibility near Env base, and no evidence for the intra-subunit flexibility near Env apex suggested by smFRET. CD4 binding increased inter-subunit distances and heterogeneity, consistent with rearrangements required for coreceptor binding. Results suggest similarities between SOSIPs and virion-bound Envs and demonstrate DEER’s relevance for immunogen design. SOSIP Env apex is 3-fold symmetric and consistent with closed prefusion structures Unliganded Env base and CD4-bound Env apex and base exhibit flexibility SOSIPs retain desired properties of immunogens; e.g., burying non-neutralizing epitopes Results allow interpretation of smFRET studies and SOSIP and virion Env structures
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Affiliation(s)
- Beth M Stadtmueller
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Michael D Bridges
- Jules Stein Eye Institute, University of California, Los Angeles, CA 90095, USA; Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
| | - Kim-Marie Dam
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Michael T Lerch
- Jules Stein Eye Institute, University of California, Los Angeles, CA 90095, USA; Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
| | - Kathryn E Huey-Tubman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Wayne L Hubbell
- Jules Stein Eye Institute, University of California, Los Angeles, CA 90095, USA; Department of Chemistry and Biochemistry, University of California, Los Angeles, CA 90095, USA
| | - Pamela J Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
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Possas C, Antunes AMDS, Lins Mendes FM, Veloso V, Martins RM, Homma A. HIV cure: global overview of bNAbs' patents and related scientific publications. Expert Opin Ther Pat 2018; 28:551-560. [PMID: 29962249 DOI: 10.1080/13543776.2018.1495708] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
INTRODUCTION This article provides a global overview of patent deposits for broadly neutralizing antibodies (bNAbs), which have emerged as a key strategy for HIV cure and future HIV vaccines. Scientific and technological barriers to the discovery of an effective HIV vaccine in the last 40 years have raised concerns on the potential for relevant advances in this area. Nevertheless, recent breakthrough studies have identified novel immune pathways for new innovative HIV vaccine and HIV cure strategies. AREAS COVERED In our patent study, we have identified in a global scale, in the last decade, a sharp increase in the number of bNAbs' patent deposits related to HIV prevention and treatment strategies, reaching 90 bNAbs in 2017, protected by 184 different patent deposits. Refining our patent search to the different stages of bNAbs' development has also allowed us to identify 12 of them already at clinical stage of research (VRC01, 10E8, 3BNC117, 10-1074, 2G12, 2F5, KD-247, 4E10, PG9, PGDM1400, PGT121, and VRC07). We describe these recent breakthroughs and discuss the prospects and limitations of these novel strategies. EXPERT OPINION Our results indicate the intellectual property outcomes of a scientific revolution in this field, expressing innovative modifications in antibodies to increase their potency and half-life, which have resulted in extremely potent antibodies that could provide novel preventive and therapeutic HIV strategies.
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Affiliation(s)
- Cristina Possas
- a Bio-Manguinhos , Oswaldo Cruz Foundation (FIOCRUZ) , Rio de Janeiro , Brazil
| | - Adelaide Maria de Souza Antunes
- b School of Chemistry , Federal University of Rio de Janeiro (EQ/UFRJ) , Rio de Janeiro , Brazil.,c c-academy, National Institute of Industrial Property (INPI) , Rio de Janeiro , Brazil
| | - Flavia Maria Lins Mendes
- b School of Chemistry , Federal University of Rio de Janeiro (EQ/UFRJ) , Rio de Janeiro , Brazil
| | - Valdiléa Veloso
- d Evandro Chagas National Institute of Infectology (INI/FIOCRUZ), Oswaldo Cruz Foundation , Rio de Janeiro , Brazil
| | | | - Akira Homma
- a Bio-Manguinhos , Oswaldo Cruz Foundation (FIOCRUZ) , Rio de Janeiro , Brazil
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Abstract
HIV-1 spreads through contacts between infected and target cells. Polarized viral budding at the contact site forms the virological synapse. Additional cellular processes, such as nanotubes, filopodia, virus accumulation in endocytic or phagocytic compartments promote efficient viral propagation. Cell-to-cell transmission allows immune evasion and likely contributes to HIV-1 spread in vivo. Anti-HIV-1 broadly neutralizing antibodies (bNAbs) defeat the majority of circulating viral strains by binding to the viral envelope glycoprotein (Env). Several bNAbs have entered clinical evaluation during the last years. It is thus important to understand their mechanism of action and to determine how they interact with infected cells. In experimental models, HIV-1 cell-to-cell transmission is sensitive to neutralization, but the effect of antibodies is often less marked than during cell-free infection. This may be due to differences in the conformation or accessibility of Env at the surface of virions and cells. In this review, we summarize the current knowledge on HIV-1 cell-to-cell transmission and discuss the role of bNAbs during this process.
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Affiliation(s)
- Jérémy Dufloo
- Virus and Immunity Unit, Department of Virology, Institut Pasteur, Paris, France.,CNRS-UMR3569, Paris, France
| | - Timothée Bruel
- Virus and Immunity Unit, Department of Virology, Institut Pasteur, Paris, France.,CNRS-UMR3569, Paris, France.,Vaccine Research Institute, Créteil, France
| | - Olivier Schwartz
- Virus and Immunity Unit, Department of Virology, Institut Pasteur, Paris, France. .,CNRS-UMR3569, Paris, France. .,Vaccine Research Institute, Créteil, France.
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Abstract
The neutralizing antibodies targeting the HIV-1 envelope protein have been a major focus for HIV therapy. Early studies with anti-HIV-1 neutralizing monoclonal antibodies (mAbs) administered to infected individuals showed some promise, as they resulted in transient reductions in plasma viremia in some recipients. However, resistant viral variants rapidly emerged. A major development during the past 6 to 7 years has been the isolation and characterization of highly potent and broadly neutralizing mAbs (bNAbs) from infected individuals known as "elite neutralizers." These "next-generation" bNAbs have been tested in animal model systems and shown to effectively control virus replication, particularly following combination immunotherapy. The success of these preclinical animal studies has led to human clinical trials using an individual bNAb for therapy. This review examines recent findings from animal models and human clinical trials and discusses the future use of bNAbs for HIV-1 treatment.
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Affiliation(s)
- Yoshiaki Nishimura
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda MD 20892
| | - Malcolm A Martin
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda MD 20892.
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Richard J, Prévost J, Baxter AE, von Bredow B, Ding S, Medjahed H, Delgado GG, Brassard N, Stürzel CM, Kirchhoff F, Hahn BH, Parsons MS, Kaufmann DE, Evans DT, Finzi A. Uninfected Bystander Cells Impact the Measurement of HIV-Specific Antibody-Dependent Cellular Cytotoxicity Responses. mBio 2018; 9:e00358-18. [PMID: 29559570 DOI: 10.1128/mBio.00358-18] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The conformation of the HIV-1 envelope glycoprotein (Env) substantially impacts antibody recognition and antibody-dependent cellular cytotoxicity (ADCC) responses. In the absence of the CD4 receptor at the cell surface, primary Envs sample a “closed” conformation that occludes CD4-induced (CD4i) epitopes. The virus controls CD4 expression through the actions of Nef and Vpu accessory proteins, thus protecting infected cells from ADCC responses. However, gp120 shed from infected cells can bind to CD4 present on uninfected bystander cells, sensitizing them to ADCC mediated by CD4i antibodies (Abs). Therefore, we hypothesized that these bystander cells could impact the interpretation of ADCC measurements. To investigate this, we evaluated the ability of antibodies to CD4i epitopes and broadly neutralizing Abs (bNAbs) to mediate ADCC measured by five ADCC assays commonly used in the field. Our results indicate that the uninfected bystander cells coated with gp120 are efficiently recognized by the CD4i ligands but not the bNabs. Consequently, the uninfected bystander cells substantially affect in vitro measurements made with ADCC assays that fail to identify responses against infected versus uninfected cells. Moreover, using an mRNA flow technique that detects productively infected cells, we found that the vast majority of HIV-1-infected cells in in vitro cultures or ex vivo samples from HIV-1-infected individuals are CD4 negative and therefore do not expose significant levels of CD4i epitopes. Altogether, our results indicate that ADCC assays unable to differentiate responses against infected versus uninfected cells overestimate responses mediated by CD4i ligands. Emerging evidence supports a role for antibody-dependent cellular cytotoxicity (ADCC) in protection against HIV-1 transmission and disease progression. However, there are conflicting reports regarding the ability of nonneutralizing antibodies targeting CD4-inducible (CD4i) Env epitopes to mediate ADCC. Here, we performed a side-by-side comparison of different methods currently being used in the field to measure ADCC responses to HIV-1. We found that assays which are unable to differentiate virus-infected from uninfected cells greatly overestimate ADCC responses mediated by antibodies to CD4i epitopes and underestimate responses mediated by broadly neutralizing antibodies (bNAbs). Our results strongly argue for the use of assays that measure ADCC against HIV-1-infected cells expressing physiologically relevant conformations of Env to evaluate correlates of protection in vaccine trials.
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Shcherbakov DN, Bakulina AY, Karpenko LI, Ilyichev AA. Broadly Neutralizing Antibodies against HIV-1 As a Novel Aspect of the Immune Response. Acta Naturae 2015; 7:11-21. [PMID: 26798488 PMCID: PMC4717246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The human immunodeficiency virus-1 (HIV-1) has the ability to evade the adaptive immune response due to high mutation rates. Soon after the discovery of HIV-1, it was originally proposed that neutralizing of antibodies to the virus occurs rarely or cannot be elicited at all. In the 1990s, there appeared reports that sera of select HIV-1-infected individuals contained antibodies capable of neutralizing different virus subtypes. Such antibodies were named broadly neutralizing antibodies (bNAbs). Since 2009, the development of new cell technologies has intensified research efforts directed at identifying new bNAbs with a neutralization potency of over 90% of primary HIV-1 isolates. These antibodies have unique characteristics which include high levels of somatic mutations and unusually long variable loops that penetrate through the glycan shield of HIV-1 Env to contact the protein surface. In this review, we will attempt to summarize the latest data on bNAbs against HIV-1 in terms of their interactions with the sites of vulnerability on HIV-1 glycoproteins.
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Affiliation(s)
- D. N. Shcherbakov
- State research center of virology and biotechnology “Vector”, Koltsovo, 630559, Novosibirsk region, Russia
- Altai State University, 61 Lenin St., 656049, Barnaul, Russia
| | - A. Y. Bakulina
- State research center of virology and biotechnology “Vector”, Koltsovo, 630559, Novosibirsk region, Russia
- Novosibirsk State University, 2 Pirogova St., 630090, Novosibirsk, Russia
| | - L. I. Karpenko
- State research center of virology and biotechnology “Vector”, Koltsovo, 630559, Novosibirsk region, Russia
| | - A. A. Ilyichev
- State research center of virology and biotechnology “Vector”, Koltsovo, 630559, Novosibirsk region, Russia
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Johnson EL, Chu H, Byrareddy SN, Spearman P, Chakraborty R. Placental Hofbauer cells assemble and sequester HIV-1 in tetraspanin-positive compartments that are accessible to broadly neutralizing antibodies. J Int AIDS Soc 2015; 18:19385. [PMID: 25623930 DOI: 10.7448/IAS.18.1.19385] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Revised: 11/11/2014] [Accepted: 12/16/2014] [Indexed: 12/23/2022] Open
Abstract
Introduction Within monocyte-derived macrophages, HIV-1 accumulates in intracellular virus-containing compartments (VCCs) that are inaccessible to the external environment, which implicate these cells as latently infected HIV-1 reservoirs. During mother-to-child transmission of HIV-1, human placental macrophages (Hofbauer cells (HCs)) are viral targets, and have been shown to be infected in vivo and sustain low levels of viral replication in vitro; however, the risk of in utero transmission is less than 7%. The role of these primary macrophages as viral reservoirs is largely undefined. The objective of this study is to define potential sites of viral assembly, accumulation and neutralization in HCs given the pivotal role of the placenta in preventing HIV-1 infection in the mother-infant dyad. Methods Term placentae from 20 HIV-1 seronegative women were obtained following caesarian section. VCCs were evaluated by 3D confocal and electron microscopy. Colocalization R values (Pearson's correlation) were quantified with colocalization module of Volocity 5.2.1. Replication kinetics and neutralization studies were evaluated using p24 ELISA. Results We demonstrate that primary HCs assemble and sequester HIV-1BaL in intracellular VCCs, which are enriched in endosomal/lysosomal markers, including CD9, CD81, CD63 and LAMP-1. Following infection, we observed HIV-1 accumulation in potentially acidic compartments, which stained intensely with Lysotracker-Red. Remarkably, these compartments are readily accessible via the cell surface and can be targeted by exogenously applied small molecules and HIV-1-specific broadly neutralizing antibodies. In addition, broadly neutralizing antibodies (4E10 and VRC01) limited viral replication by HIV-1-infected HCs, which may be mediated by FcγRI. Conclusions These findings suggest that placental HCs possess intrinsic adaptations facilitating unique sequestration of HIV-1, and may serve as a protective viral reservoir to permit viral neutralization and/or antiretroviral drug entry in utero.
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