1
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Galkin A, Chen Y, Guenaga J, O'Dell S, Acevedo R, Steinhardt JJ, Wang Y, Wilson R, Chiang CI, Doria-Rose N, Grishaev AV, Mascola JR, Li Y. HIV-1 gp120-CD4-Induced Antibody Complex Elicits CD4 Binding Site-Specific Antibody Response in Mice. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2020; 204:1543-1561. [PMID: 32066595 PMCID: PMC7065964 DOI: 10.4049/jimmunol.1901051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Accepted: 12/31/2019] [Indexed: 11/19/2022]
Abstract
Elicitation of broadly neutralizing Ab (bNAb) responses toward the conserved HIV-1 envelope (Env) CD4 binding site (CD4bs) by vaccination is an important goal for vaccine development and yet to be achieved. The outcome of previous immunogenicity studies suggests that the limited accessibility of the CD4bs and the presence of predominant nonneutralizing determinants (nND) on Env may impede the elicitation of bNAbs and their precursors by vaccination. In this study, we designed a panel of novel immunogens that 1) preferentially expose the CD4bs by selective elimination of glycosylation sites flanking the CD4bs, and 2) minimize the nND immune response by engineering fusion proteins consisting of gp120 Core and one or two CD4-induced (CD4i) mAbs for masking nND epitopes, referred to as gp120-CD4i fusion proteins. As expected, the fusion proteins possess improved antigenicity with retained affinity for VRC01-class, CD4bs-directed bNAbs and dampened affinity for nonneutralizing Abs. We immunized C57BL/6 mice with these fusion proteins and found that overall the fusion proteins elicit more focused CD4bs Ab response than prototypical gp120 Core by serological analysis. Consistently, we found that mice immunized with selected gp120-CD4i fusion proteins have higher frequencies of germinal center-activated B cells and CD4bs-directed memory B cells than those inoculated with parental immunogens. We isolated three mAbs from mice immunized with selected gp120-CD4i fusion proteins and found that their footprints on Env are similar to VRC01-class bNAbs. Thus, using gp120-CD4i fusion proteins with selective glycan deletion as immunogens could focus Ab response toward CD4bs epitope.
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MESH Headings
- AIDS Vaccines/administration & dosage
- AIDS Vaccines/genetics
- AIDS Vaccines/immunology
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/genetics
- Antibodies, Monoclonal/immunology
- Antibodies, Neutralizing/blood
- Antibodies, Neutralizing/immunology
- Binding Sites, Antibody/genetics
- Binding Sites, Antibody/immunology
- CD4 Antigens/immunology
- CD4 Antigens/metabolism
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Female
- HIV Antibodies/blood
- HIV Antibodies/immunology
- HIV Envelope Protein gp120/genetics
- HIV Envelope Protein gp120/immunology
- HIV Infections/blood
- HIV Infections/immunology
- HIV Infections/prevention & control
- HIV Infections/virology
- HIV-1/genetics
- HIV-1/immunology
- Humans
- Immunogenicity, Vaccine
- Mice
- Models, Animal
- Recombinant Fusion Proteins/administration & dosage
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/immunology
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
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Affiliation(s)
- Andrey Galkin
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201
- Center of Biomolecular Therapeutics, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Yajing Chen
- Department of Immunology and Microbiology, Scripps Research, La Jolla, CA 92037
| | - Javier Guenaga
- International AIDS Vaccine Initiative Neutralizing Antibody Center at Scripps Research, La Jolla, CA 92037
| | - Sijy O'Dell
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892; and
| | - Roderico Acevedo
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850
| | - James J Steinhardt
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850
| | - Yimeng Wang
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850
| | - Richard Wilson
- International AIDS Vaccine Initiative Neutralizing Antibody Center at Scripps Research, La Jolla, CA 92037
| | - Chi-I Chiang
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850
| | - Nicole Doria-Rose
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892; and
| | - Alexander V Grishaev
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850
- National Institute of Standards and Technology, Gaithersburg, MD 20899
| | - John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892; and
| | - Yuxing Li
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850;
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201
- Center of Biomolecular Therapeutics, University of Maryland School of Medicine, Baltimore, MD 21201
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2
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Dosenovic P, Pettersson AK, Wall A, Thientosapol ES, Feng J, Weidle C, Bhullar K, Kara EE, Hartweger H, Pai JA, Gray MD, Parks KR, Taylor JJ, Pancera M, Stamatatos L, Nussenzweig MC, McGuire AT. Anti-idiotypic antibodies elicit anti-HIV-1-specific B cell responses. J Exp Med 2019; 216:2316-2330. [PMID: 31345931 PMCID: PMC6780999 DOI: 10.1084/jem.20190446] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Revised: 05/29/2019] [Accepted: 06/24/2019] [Indexed: 12/23/2022] Open
Abstract
Human anti-HIV-1 broadly neutralizing antibodies (bNAbs) protect against infection in animal models. However, bNAbs have not been elicited by vaccination in diverse wild-type animals or humans, in part because B cells expressing the precursors of these antibodies do not recognize most HIV-1 envelopes (Envs). Immunogens have been designed that activate these B cell precursors in vivo, but they also activate competing off-target responses. Here we report on a complementary approach to expand specific B cells using an anti-idiotypic antibody, iv8, that selects for naive human B cells expressing immunoglobulin light chains with 5-amino acid complementarity determining region 3s, a key feature of anti-CD4 binding site (CD4bs)-specific VRC01-class antibodies. In mice, iv8 induced target cells to expand and mature in the context of a polyclonal immune system and produced serologic responses targeting the CD4bs on Env. In summary, the results demonstrate that an anti-idiotypic antibody can specifically recognize and expand rare B cells that express VRC01-class antibodies against HIV-1.
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Affiliation(s)
- Pia Dosenovic
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY
| | | | - Abigail Wall
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Eddy S Thientosapol
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY
| | - Junli Feng
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Connor Weidle
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Komal Bhullar
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY
| | - Ervin E Kara
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY
| | - Harald Hartweger
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY
| | - Joy A Pai
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY
| | - Matthew D Gray
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - K Rachael Parks
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA.,University of Washington University of Washington, Department of Global Health, Seattle, WA
| | - Justin J Taylor
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA.,University of Washington University of Washington, Department of Global Health, Seattle, WA.,University of Washington University of Washington, Department of Immunology, Seattle, WA
| | - Marie Pancera
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Leonidas Stamatatos
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA .,University of Washington University of Washington, Department of Global Health, Seattle, WA
| | - Michel C Nussenzweig
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY .,Howard Hughes Medical Institute, Chevy Chase, MD
| | - Andrew T McGuire
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA .,University of Washington University of Washington, Department of Global Health, Seattle, WA
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3
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Antibody-Mediated Therapy against HIV/AIDS: Where Are We Standing Now? J Pathog 2018; 2018:8724549. [PMID: 29973995 PMCID: PMC6009031 DOI: 10.1155/2018/8724549] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Revised: 04/10/2018] [Accepted: 04/26/2018] [Indexed: 11/17/2022] Open
Abstract
Acquired immunodeficiency syndrome (AIDS) cases are on the rise globally. To date, there is still no effective measure to eradicate the causative agent, human immunodeficiency virus (HIV). Highly active antiretroviral therapy (HAART) is being used in HIV/AIDS management, but it results in long-term medication and has major drawbacks such as multiple side effects, high cost, and increasing the generation rate of escape mutants. In addition, HAART does not control HIV-related complications, and hence more medications and further management are required. With this, other alternatives are urgently needed. In the past, small-molecule inhibitors have shown potent antiviral effects, and some of them are now being evaluated in clinical trials. The challenges in developing these small molecules for clinical use include the off-target effect, poor stability, and low bioavailability. On the other hand, antibody-mediated therapy has emerged as an important therapeutic modality for anti-HIV therapeutics development. Many antiviral antibodies, namely, broad neutralizing antibodies (bnAbs) against multiple strains of HIV, have shown promising effects in vitro and in animal studies; further studies are ongoing in clinical trials to evaluate their uses in clinical applications. This short review aims to discuss the current development of therapeutic antibodies against HIV and the challenges in adopting them for clinical use.
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4
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Havenar-Daughton C, Carnathan DG, Torrents de la Peña A, Pauthner M, Briney B, Reiss SM, Wood JS, Kaushik K, van Gils MJ, Rosales SL, van der Woude P, Locci M, Le KM, de Taeye SW, Sok D, Mohammed AUR, Huang J, Gumber S, Garcia A, Kasturi SP, Pulendran B, Moore JP, Ahmed R, Seumois G, Burton DR, Sanders RW, Silvestri G, Crotty S. Direct Probing of Germinal Center Responses Reveals Immunological Features and Bottlenecks for Neutralizing Antibody Responses to HIV Env Trimer. Cell Rep 2017; 17:2195-2209. [PMID: 27880897 DOI: 10.1016/j.celrep.2016.10.085] [Citation(s) in RCA: 137] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 09/16/2016] [Accepted: 10/25/2016] [Indexed: 02/06/2023] Open
Abstract
Generating tier 2 HIV-neutralizing antibody (nAb) responses by immunization remains a challenging problem, and the immunological barriers to induction of such responses with Env immunogens remain unclear. Here, some rhesus monkeys developed autologous tier 2 nAbs upon HIV Env trimer immunization (SOSIP.v5.2) whereas others did not. This was not because HIV Env trimers were immunologically silent because all monkeys made similar ELISA-binding antibody responses; the key difference was nAb versus non-nAb responses. We explored the immunological barriers to HIV nAb responses by combining a suite of techniques, including longitudinal lymph node fine needle aspirates. Unexpectedly, nAb development best correlated with booster immunization GC B cell magnitude and Tfh characteristics of the Env-specific CD4 T cells. Notably, these factors distinguished between successful and unsuccessful antibody responses because GC B cell frequencies and stoichiometry to GC Tfh cells correlated with nAb development, but did not correlate with total Env Ab binding titers.
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Affiliation(s)
- Colin Havenar-Daughton
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA; Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA
| | - Diane G Carnathan
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
| | - Alba Torrents de la Peña
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Matthias Pauthner
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Bryan Briney
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Samantha M Reiss
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA; Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA
| | - Jennifer S Wood
- Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
| | - Kirti Kaushik
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA; Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA
| | - Marit J van Gils
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Sandy L Rosales
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA
| | - Patricia van der Woude
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Michela Locci
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA; Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA
| | - Khoa M Le
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Steven W de Taeye
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Devin Sok
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | - Jessica Huang
- Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Sanjeev Gumber
- Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
| | - AnaPatricia Garcia
- Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA
| | - Sudhir P Kasturi
- Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Bali Pulendran
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - John P Moore
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Rafi Ahmed
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Grégory Seumois
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA
| | - Dennis R Burton
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA; Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA
| | - Rogier W Sanders
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands; Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, NY 10065, USA
| | - Guido Silvestri
- Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Yerkes National Primate Research Center, Emory University, Atlanta, GA 30322, USA; Emory Vaccine Center, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Shane Crotty
- Division of Vaccine Discovery, La Jolla Institute for Allergy and Immunology, La Jolla, CA 92037, USA; Scripps Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, La Jolla, CA 92037, USA; Department of Medicine, Division of Infectious Diseases, University of California, San Diego, La Jolla, CA 92037, USA.
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5
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Ahmed Y, Tian M, Gao Y. Development of an anti-HIV vaccine eliciting broadly neutralizing antibodies. AIDS Res Ther 2017; 14:50. [PMID: 28893278 PMCID: PMC5594608 DOI: 10.1186/s12981-017-0178-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 08/11/2017] [Indexed: 11/17/2022] Open
Abstract
The extreme HIV diversity posts a great challenge on development of an effective anti-HIV vaccine. To solve this problem, it is crucial to discover an appropriate immunogens and strategies that are able to prevent the transmission of the diverse viruses that are circulating in the world. Even though there have been a number of broadly neutralizing anti-HIV antibodies (bNAbs) been discovered in recent years, induction of such antibodies to date has only been observed in HIV-1 infection. Here, in this mini review, we review the progress in development of HIV vaccine in eliciting broad immune response, especially production of bNAbs, discuss possible strategies, such as polyvalent sequential vaccination, that facilitates B cell maturation leading to bNAb response.
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6
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Martinez-Murillo P, Tran K, Guenaga J, Lindgren G, Àdori M, Feng Y, Phad GE, Vázquez Bernat N, Bale S, Ingale J, Dubrovskaya V, O'Dell S, Pramanik L, Spångberg M, Corcoran M, Loré K, Mascola JR, Wyatt RT, Karlsson Hedestam GB. Particulate Array of Well-Ordered HIV Clade C Env Trimers Elicits Neutralizing Antibodies that Display a Unique V2 Cap Approach. Immunity 2017; 46:804-817.e7. [PMID: 28514687 DOI: 10.1016/j.immuni.2017.04.021] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 02/27/2017] [Accepted: 04/26/2017] [Indexed: 01/22/2023]
Abstract
The development of soluble envelope glycoprotein (Env) mimetics displaying ordered trimeric symmetry has ushered in a new era in HIV-1 vaccination. The recently reported native, flexibly linked (NFL) design allows the generation of native-like trimers from clinical isolates at high yields and homogeneity. As the majority of infections world-wide are of the clade C subtype, we examined responses in non-human primates to well-ordered subtype C 16055 trimers administered in soluble or high-density liposomal formats. We detected superior germinal center formation and enhanced autologous neutralizing antibodies against the neutralization-resistant (tier 2) 16055 virus following inoculation of liposome-arrayed trimers. Epitope mapping of the neutralizing monoclonal antibodies (mAbs) indicated major contacts with the V2 apex, and 3D electron microscopy reconstructions of Fab-trimer complexes revealed a horizontal binding angle to the Env spike. These vaccine-elicited mAbs target the V2 cap, demonstrating a means to accomplish tier 2 virus neutralization by penetrating the dense N-glycan shield.
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Affiliation(s)
- Paola Martinez-Murillo
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Karen Tran
- IAVI Neutralizing Antibody Center, Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Javier Guenaga
- IAVI Neutralizing Antibody Center, Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Gustaf Lindgren
- Immunology and Allergy Unit, Department of Medicine, Karolinska Institutet, 171 77 Solna, Sweden
| | - Monika Àdori
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Yu Feng
- IAVI Neutralizing Antibody Center, Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Ganesh E Phad
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Néstor Vázquez Bernat
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Shridhar Bale
- IAVI Neutralizing Antibody Center, Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jidnyasa Ingale
- IAVI Neutralizing Antibody Center, Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Viktoriya Dubrovskaya
- IAVI Neutralizing Antibody Center, Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Sijy O'Dell
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lotta Pramanik
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Mats Spångberg
- Astrid Fagraeus Laboratory, Comparative Medicine, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Martin Corcoran
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, SE-171 77 Stockholm, Sweden
| | - Karin Loré
- Immunology and Allergy Unit, Department of Medicine, Karolinska Institutet, 171 77 Solna, Sweden
| | - John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Richard T Wyatt
- IAVI Neutralizing Antibody Center, Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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7
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Karlsson Hedestam GB, Guenaga J, Corcoran M, Wyatt RT. Evolution of B cell analysis and Env trimer redesign. Immunol Rev 2017; 275:183-202. [PMID: 28133805 DOI: 10.1111/imr.12515] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
HIV-1 and its surface envelope glycoproteins (Env), gp120 and gp41, have evolved immune evasion strategies that render the elicitation of effective antibody responses to the functional Env entry unit extremely difficult. HIV-1 establishes chronic infection and stimulates vigorous immune responses in the human host; forcing selection of viral variants that escape cellular and antibody (Ab)-mediated immune pressure, yet possess contemporary fitness. Successful survival of fit variants through the gauntlet of the human immune system make this virus and these glycoproteins a formidable challenge to target by vaccination, requiring a systematic approach to Env mimetic immunogen design and evaluation of elicited responses. Here, we review key aspects of HIV-1 Env immunogenicity and immunogen re-design, based on experimental data generated by us and others over the past decade or more. We further provide rationale and details regarding the use of newly evolving tools to analyze B cell responses, including approaches to use next generation sequencing for antibody lineage tracing and B cell fate mapping. Together, these developments offer opportunities to address long-standing questions about the establishment of effective B cell immunity elicited by vaccination, not just against HIV-1.
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Affiliation(s)
| | - Javier Guenaga
- Department of Immunology and Microbial Science, IAVI Neutralizing Antibody Center at TSRI, La Jolla, CA, USA
| | - Martin Corcoran
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Richard T Wyatt
- Department of Immunology and Microbial Science, IAVI Neutralizing Antibody Center at TSRI, La Jolla, CA, USA.,The Scripps CHAVI-ID, La Jolla, CA, USA
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8
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Escolano A, Dosenovic P, Nussenzweig MC. Progress toward active or passive HIV-1 vaccination. J Exp Med 2016; 214:3-16. [PMID: 28003309 PMCID: PMC5206506 DOI: 10.1084/jem.20161765] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 11/30/2016] [Accepted: 12/07/2016] [Indexed: 12/31/2022] Open
Abstract
AIDS is a preventable disease. Nevertheless, according to UNAIDS, 2.1 million individuals were infected with HIV-1 in 2015 worldwide. An effective vaccine is highly desirable. Most vaccines in clinical use today prevent infection because they elicit antibodies that block pathogen entry. Consistent with this general rule, studies in experimental animals have shown that broadly neutralizing antibodies to HIV-1 can prevent infection, suggesting that a vaccine that elicits such antibodies would be protective. However, despite significant efforts over the last 30 years, attempts to elicit broadly HIV-1 neutralizing antibodies by vaccination failed until recent experiments in genetically engineered mice were finally successful. Here, we review the key breakthroughs and remaining obstacles to the development of active and passive HIV-1 vaccines.
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Affiliation(s)
- Amelia Escolano
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065
| | - Pia Dosenovic
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065
| | - Michel C Nussenzweig
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065 .,Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065
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9
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Chen Y, Wilson R, O'Dell S, Guenaga J, Feng Y, Tran K, Chiang CI, Arendt HE, DeStefano J, Mascola JR, Wyatt RT, Li Y. An HIV-1 Env-Antibody Complex Focuses Antibody Responses to Conserved Neutralizing Epitopes. THE JOURNAL OF IMMUNOLOGY 2016; 197:3982-3998. [PMID: 27815444 DOI: 10.4049/jimmunol.1601134] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 08/31/2016] [Indexed: 11/19/2022]
Abstract
Elicitation of broadly neutralizing Ab (bNAb) responses to the conserved elements of the HIV-1 envelope glycoproteins (Env), including the primary receptor CD4 binding site (CD4bs), is a major focus of vaccine development yet to be accomplished. However, a large number of CD4bs-directed bNAbs have been isolated from HIV-1-infected individuals. Comparison of the routes of binding used by the CD4bs-directed bNAbs from patients and the vaccine-elicited CD4bs-directed mAbs indicates that the latter fail to neutralize primary virus isolates because they approach the Env spike with a vertical angle and contact the specific surface residues occluded in the native spike, including the bridging sheet on gp120. To preferentially expose the CD4bs and direct the immune response away from the bridging sheet, resulting in an altered angle of approach, we engineered an immunogen consisting of gp120 core in complex with the prototypic CD4-induced Ab, 17b. This mAb directly contacts the bridging sheet but not the CD4bs. The complex was further stabilized by chemical crosslinking to prevent dissociation. Rabbits immunized with the crosslinked complex displayed earlier affinity maturation, achieving tier 1 virus neutralization compared with animals immunized with gp120 core alone. Immunization with the crosslinked complex induced transient Ab responses with binding specificity similar to the CD4bs-directed bNAbs. mAbs derived from complex-immunized rabbits displayed footprints on gp120 more distal from the bridging sheet as compared with previous vaccine-elicited CD4bs Abs, indicating that Env-Ab complexes effectively dampen immune responses to undesired immunodominant bridging sheet determinants.
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Affiliation(s)
- Yajing Chen
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
| | - Richard Wilson
- International AIDS Vaccine Initiative Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037
| | - Sijy O'Dell
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Javier Guenaga
- International AIDS Vaccine Initiative Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037
| | - Yu Feng
- International AIDS Vaccine Initiative Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037
| | - Karen Tran
- International AIDS Vaccine Initiative Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037
| | - Chi-I Chiang
- Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850
| | | | | | - John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Richard T Wyatt
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037.,International AIDS Vaccine Initiative Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037.,Scripps Center for HIV Vaccine Immunogen Discovery, La Jolla, CA 92037
| | - Yuxing Li
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037; .,International AIDS Vaccine Initiative Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037.,Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850
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10
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Antibodies Elicited by Multiple Envelope Glycoprotein Immunogens in Primates Neutralize Primary Human Immunodeficiency Viruses (HIV-1) Sensitized by CD4-Mimetic Compounds. J Virol 2016; 90:5031-5046. [PMID: 26962221 DOI: 10.1128/jvi.03211-15] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 02/26/2016] [Indexed: 12/16/2022] Open
Abstract
UNLABELLED The human immunodeficiency virus (HIV-1) envelope glycoproteins (Env) mediate virus entry through a series of complex conformational changes triggered by binding to the receptors CD4 and CCR5/CXCR4. Broadly neutralizing antibodies that recognize conserved Env epitopes are thought to be an important component of a protective immune response. However, to date, HIV-1 Env immunogens that elicit broadly neutralizing antibodies have not been identified, creating hurdles for vaccine development. Small-molecule CD4-mimetic compounds engage the CD4-binding pocket on the gp120 exterior Env and induce Env conformations that are highly sensitive to neutralization by antibodies, including antibodies directed against the conserved Env region that interacts with CCR5/CXCR4. Here, we show that CD4-mimetic compounds sensitize primary HIV-1 to neutralization by antibodies that can be elicited in monkeys and humans within 6 months by several Env vaccine candidates, including gp120 monomers. Monoclonal antibodies directed against the gp120 V2 and V3 variable regions were isolated from the immunized monkeys and humans; these monoclonal antibodies neutralized a primary HIV-1 only when the virus was sensitized by a CD4-mimetic compound. Thus, in addition to their direct antiviral effect, CD4-mimetic compounds dramatically enhance the HIV-1-neutralizing activity of antibodies that can be elicited with currently available immunogens. Used as components of microbicides, the CD4-mimetic compounds might increase the protective efficacy of HIV-1 vaccines. IMPORTANCE Preventing HIV-1 transmission is a high priority for global health. Eliciting antibodies that can neutralize transmitted strains of HIV-1 is difficult, creating problems for the development of an effective vaccine. We found that small-molecule CD4-mimetic compounds sensitize HIV-1 to antibodies that can be elicited in vaccinated humans and monkeys. These results suggest an approach to prevent HIV-1 sexual transmission in which a virus-sensitizing microbicide is combined with a vaccine.
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11
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Hessell AJ, Malherbe DC, Pissani F, McBurney S, Krebs SJ, Gomes M, Pandey S, Sutton WF, Burwitz BJ, Gray M, Robins H, Park BS, Sacha JB, LaBranche CC, Fuller DH, Montefiori DC, Stamatatos L, Sather DN, Haigwood NL. Achieving Potent Autologous Neutralizing Antibody Responses against Tier 2 HIV-1 Viruses by Strategic Selection of Envelope Immunogens. THE JOURNAL OF IMMUNOLOGY 2016; 196:3064-78. [PMID: 26944928 DOI: 10.4049/jimmunol.1500527] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 01/15/2016] [Indexed: 11/19/2022]
Abstract
Advancement in immunogen selection and vaccine design that will rapidly elicit a protective Ab response is considered critical for HIV vaccine protective efficacy. Vaccine-elicited Ab responses must therefore have the capacity to prevent infection by neutralization-resistant phenotypes of transmitted/founder (T/F) viruses that establish infection in humans. Most vaccine candidates to date have been ineffective at generating Abs that neutralize T/F or early variants. In this study, we report that coimmunizing rhesus macaques with HIV-1 gp160 DNA and gp140 trimeric protein selected from native envelope gene sequences (envs) induced neutralizing Abs against Tier 2 autologous viruses expressing cognate envelope (Env). The Env immunogens were selected from envs emerging during the earliest stages of neutralization breadth developing within the first 2 years of infection in two clade B-infected human subjects. Moreover, the IgG responses in macaques emulated the targeting to specific regions of Env known to be associated with autologous and heterologous neutralizing Abs developed within the human subjects. Furthermore, we measured increasing affinity of macaque polyclonal IgG responses over the course of the immunization regimen that correlated with Tier 1 neutralization. In addition, we report firm correlations between Tier 2 autologous neutralization and Tier 1 heterologous neutralization, as well as overall TZM-bl breadth scores. Additionally, the activation of Env-specific follicular helper CD4 T cells in lymphocytes isolated from inguinal lymph nodes of vaccinated macaques correlated with Tier 2 autologous neutralization. These results demonstrate the potential for native Env derived from subjects at the time of neutralization broadening as effective HIV vaccine elements.
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Affiliation(s)
- Ann J Hessell
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Delphine C Malherbe
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Franco Pissani
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006; Military HIV Research Program, Silver Spring, MD 20889
| | - Sean McBurney
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Shelly J Krebs
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Portland, OR 97239
| | - Michelle Gomes
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Shilpi Pandey
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - William F Sutton
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Benjamin J Burwitz
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006; Vaccine and Gene Therapy Institute, Oregon Health and Science University, Portland, OR 97239
| | | | - Harlan Robins
- Fred Hutchinson Cancer Research Center, Seattle, WA 98109
| | - Byung S Park
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006
| | - Jonah B Sacha
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006; Vaccine and Gene Therapy Institute, Oregon Health and Science University, Portland, OR 97239
| | - Celia C LaBranche
- Department of Surgery, Duke University Medical Center, Durham, NC 27708
| | - Deborah H Fuller
- Department of Microbiology, University of Washington, Seattle, WA 98195; and
| | | | | | | | - Nancy L Haigwood
- Oregon National Primate Research Center, Oregon Health & Science University, Beaverton, OR 97006; Molecular Microbiology and Immunology, School of Medicine, Oregon Health & Science University, Portland, OR 97239
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12
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Tuero I, Mohanram V, Musich T, Miller L, Vargas-Inchaustegui DA, Demberg T, Venzon D, Kalisz I, Kalyanaraman VS, Pal R, Ferrari MG, LaBranche C, Montefiori DC, Rao M, Vaccari M, Franchini G, Barnett SW, Robert-Guroff M. Mucosal B Cells Are Associated with Delayed SIV Acquisition in Vaccinated Female but Not Male Rhesus Macaques Following SIVmac251 Rectal Challenge. PLoS Pathog 2015; 11:e1005101. [PMID: 26267144 PMCID: PMC4534401 DOI: 10.1371/journal.ppat.1005101] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Accepted: 07/21/2015] [Indexed: 12/02/2022] Open
Abstract
Many viral infections, including HIV, exhibit sex-based pathogenic differences. However, few studies have examined vaccine-related sex differences. We compared immunogenicity and protective efficacy of monomeric SIV gp120 with oligomeric SIV gp140 in a pre-clinical rhesus macaque study and explored a subsequent sex bias in vaccine outcome. Each immunization group (16 females, 8 males) was primed twice mucosally with replication-competent Ad-recombinants encoding SIVsmH4env/rev, SIV239gag and SIV239nefΔ1–13 and boosted twice intramuscularly with SIVmac239 monomeric gp120 or oligomeric gp140 in MF59 adjuvant. Controls (7 females, 5 males) received empty Ad and MF59. Up to 9 weekly intrarectal challenges with low-dose SIVmac251 were administered until macaques became infected. We assessed vaccine-induced binding, neutralizing, and non-neutralizing antibodies, Env-specific memory B cells and plasmablasts/plasma cells (PB/PC) in bone marrow and rectal tissue, mucosal Env-specific antibodies, and Env-specific T-cells. Post-challenge, only one macaque (gp140-immunized) remained uninfected. However, SIV acquisition was significantly delayed in vaccinated females but not males, correlated with Env-specific IgA in rectal secretions, rectal Env-specific memory B cells, and PC in rectal tissue. These results extend previous correlations of mucosal antibodies and memory B cells with protective efficacy. The gp140 regimen was more immunogenic, stimulating elevated gp140 and cyclic V2 binding antibodies, ADCC and ADCP activities, bone marrow Env-specific PB/PC, and rectal gp140-specific IgG. However, immunization with gp120, the form of envelope immunogen used in RV144, the only vaccine trial to show some efficacy, provided more significant acquisition delay. Further over 40 weeks of follow-up, no gp120 immunized macaques met euthanasia criteria in contrast to 7 gp140-immunized and 2 control animals. Although males had higher binding antibodies than females, ADCC and ADCP activities were similar. The complex challenge outcomes may reflect differences in IgG subtypes, Fc glycosylation, Fc-R polymorphisms, and/or the microbiome, key areas for future studies. This first demonstration of a sex-difference in SIV vaccine-induced protection emphasizes the need for sex-balancing in vaccine trials. Our results highlight the importance of mucosal immunity and memory B cells at the SIV exposure site for protection. Viral infections can have different disease courses in men and women. Following HIV infection, women generally exhibit lower viral loads and higher CD4 counts than men, but paradoxically progress faster to AIDS. Sex differences result from effects of X-linked genes and hormonal influences, and are believed to be largely based on immune response differences. Nevertheless, little is known about potential sex differences following vaccination. Here we report for the first time a sex bias in response to a SIV vaccine in rhesus macaques, showing that female animals were better protected against acquisition of SIV compared to males. The vaccine-induced immune responses that contributed to this better protection were viral-specific antibodies and immune antibody-secreting B cells, both at the local rectal site of SIV exposure. These results suggest that HIV/SIV vaccines should be better designed to target mucosal exposure sites. Additionally, they indicate that more vaccine studies should include animals of both sexes to address potential differences. Our study also illustrates that inclusion of both sexes can lead to greater complexity in vaccine trial outcomes, necessitating more in depth analyses. However, we believe sex balancing to be particularly important, as approximately 50% of HIV infections worldwide occur in women.
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Affiliation(s)
- Iskra Tuero
- Immune Biology of Retroviral Infection Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Venkatramanan Mohanram
- Immune Biology of Retroviral Infection Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Thomas Musich
- Immune Biology of Retroviral Infection Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Leia Miller
- Immune Biology of Retroviral Infection Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Diego A. Vargas-Inchaustegui
- Immune Biology of Retroviral Infection Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Thorsten Demberg
- Immune Biology of Retroviral Infection Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - David Venzon
- Biostatistics and Data Management Section, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Irene Kalisz
- Advanced Bioscience Laboratories, Inc., Rockville, Maryland, United States of America
| | - V. S. Kalyanaraman
- Advanced Bioscience Laboratories, Inc., Rockville, Maryland, United States of America
| | - Ranajit Pal
- Advanced Bioscience Laboratories, Inc., Rockville, Maryland, United States of America
| | - Maria Grazia Ferrari
- Advanced Bioscience Laboratories, Inc., Rockville, Maryland, United States of America
| | - Celia LaBranche
- Duke University Medical Center, Durham, North Carolina, United States of America
| | - David C. Montefiori
- Duke University Medical Center, Durham, North Carolina, United States of America
| | - Mangala Rao
- USMHRP, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Monica Vaccari
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Genoveffa Franchini
- Animal Models and Retroviral Vaccines Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Susan W. Barnett
- Novartis Vaccines, Cambridge, Massachusetts, United States of America
| | - Marjorie Robert-Guroff
- Immune Biology of Retroviral Infection Section, Vaccine Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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13
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Phad GE, Vázquez Bernat N, Feng Y, Ingale J, Martinez Murillo PA, O'Dell S, Li Y, Mascola JR, Sundling C, Wyatt RT, Karlsson Hedestam GB. Diverse antibody genetic and recognition properties revealed following HIV-1 envelope glycoprotein immunization. THE JOURNAL OF IMMUNOLOGY 2015; 194:5903-14. [PMID: 25964491 DOI: 10.4049/jimmunol.1500122] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Accepted: 04/15/2015] [Indexed: 11/19/2022]
Abstract
Isolation of mAbs elicited by vaccination provides opportunities to define the development of effective immunity. Ab responses elicited by current HIV-1 envelope glycoprotein (Env) immunogens display narrow neutralizing activity with limited capacity to block infection by tier 2 viruses. Intense work in the field suggests that improved Env immunogens are forthcoming, and it is therefore important to concurrently develop approaches to investigate the quality of vaccine-elicited responses at a higher level of resolution. In this study, we cloned a representative set of mAbs elicited by a model Env immunogen in rhesus macaques and comprehensively characterized their genetic and functional properties. The mAbs were genetically diverse, even within groups of Abs targeting the same subregion of Env, consistent with a highly polyclonal response. mAbs directed against two subdeterminants of Env, the CD4 binding site and V region 3, could in part account for the neutralizing activity observed in the plasma of the animal from which they were cloned, demonstrating the power of mAb isolation for a detailed understanding of the elicited response. Finally, through comparative analyses of mAb binding and neutralizing capacity of HIV-1 using matched Envs, we demonstrate complex relationships between epitope recognition and accessibility, highlighting the protective quaternary packing of the HIV-1 spike relative to vaccine-induced mAbs.
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Affiliation(s)
- Ganesh E Phad
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Néstor Vázquez Bernat
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Yu Feng
- International AIDS Vaccine Initiative, Neutralizing Antibody Center, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
| | - Jidnyasa Ingale
- International AIDS Vaccine Initiative, Neutralizing Antibody Center, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
| | | | - Sijy O'Dell
- Vaccine Research Center, National Institutes of Health, Bethesda, MD 20892
| | - Yuxing Li
- International AIDS Vaccine Initiative, Neutralizing Antibody Center, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037; Institute for Bioscience and Biotechnology Research, University of Maryland, Rockville, MD 20850; and
| | - John R Mascola
- Vaccine Research Center, National Institutes of Health, Bethesda, MD 20892
| | - Christopher Sundling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, 171 77 Stockholm, Sweden; Immunology Division, Garvan Institute of Medical Research, Darlinghurst, New South Wales 2010, Australia
| | - Richard T Wyatt
- International AIDS Vaccine Initiative, Neutralizing Antibody Center, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037
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14
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Primate immune responses to HIV-1 Env formulated in the saponin-based adjuvant AbISCO-100 in the presence or absence of TLR9 co-stimulation. Sci Rep 2015; 5:8925. [PMID: 25762407 PMCID: PMC4356977 DOI: 10.1038/srep08925] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 02/11/2015] [Indexed: 11/08/2022] Open
Abstract
Protein-based vaccines require adjuvants to achieve optimal responses. Toll-like receptor (TLR) 9 agonists were previously shown to improve responses to protein-based vaccines, such as the Hepatitis B virus vaccine formulated in alum. Here, we used CpG-C together with the clinically relevant saponin-based adjuvant AbISCO-100/Matrix-M (AbISCO), to assess if TLR9 co-stimulation would quantitatively or qualitatively modulate HIV-1 envelope glycoprotein (Env)-specific B and T cell responses in rhesus macaques. The macaques were inoculated with soluble Env trimers in AbISCO, with or without the addition of CpG-C, using an interval similar to the Hepatitis B virus vaccine. Following a comprehensive evaluation of antigen-specific responses in multiple immune compartments, we show that the Env-specific circulating IgG, memory B cells and plasma cells displayed similar kinetics and magnitude in the presence or absence of CpG-C and that there was no apparent difference between the two groups in the elicited HIV-1 neutralizing antibody titers or antigen-specific CD4+ T cell responses. Importantly, the control of SHIV viremia was significantly improved in animals from both Env-immunized groups relative to adjuvant alone controls, demonstrating the potential of AbISCO to act as a stand-alone adjuvant for Env-based vaccines.
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15
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Grimm SK, Battles MB, Ackerman ME. Directed evolution of a yeast-displayed HIV-1 SOSIP gp140 spike protein toward improved expression and affinity for conformational antibodies. PLoS One 2015; 10:e0117227. [PMID: 25688555 PMCID: PMC4331506 DOI: 10.1371/journal.pone.0117227] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 12/22/2014] [Indexed: 11/19/2022] Open
Abstract
Design of an envelope-based immunogen capable of inducing a broadly neutralizing antibody response is thought to be key to the development of a protective HIV-1 vaccine. However, the broad diversity of viral variants and a limited ability to produce native envelope have hampered such design efforts. Here we describe adaptation of the yeast display system and use of a combinatorial protein engineering approach to permit directed evolution of HIV envelope variants. Because the intrinsic instability and complexity of this trimeric glycoprotein has greatly impeded the development of immunogens that properly represent the structure of native envelope, this platform addresses an essential need for methodologies with the capacity to rapidly engineer HIV spike proteins towards improved homogeneity, stability, and presentation of neutralizing epitopes. We report for the first time the display of a designed SOSIP gp140 on yeast, and the in vitro evolution of derivatives with greatly improved expression and binding to conformation-dependent antibodies. These efforts represent an initial and critical step toward the ability to rapidly engineer HIV-1 envelope immunogens via directed evolution.
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Affiliation(s)
- Sebastian K. Grimm
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States of America
| | - Michael B. Battles
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States of America
| | - Margaret E. Ackerman
- Thayer School of Engineering at Dartmouth, Hanover, New Hampshire, United States of America
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16
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Bowles EJ, Schiffner T, Rosario M, Needham GA, Ramaswamy M, McGouran J, Kessler B, LaBranche C, McMichael AJ, Montefiori D, Sattentau QJ, Hanke T, Stewart-Jones GBE. Comparison of neutralizing antibody responses elicited from highly diverse polyvalent heterotrimeric HIV-1 gp140 cocktail immunogens versus a monovalent counterpart in rhesus macaques. PLoS One 2014; 9:e114709. [PMID: 25490553 PMCID: PMC4260879 DOI: 10.1371/journal.pone.0114709] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 11/12/2014] [Indexed: 12/22/2022] Open
Abstract
Eliciting neutralizing antibodies capable of inactivating a broad spectrum of HIV-1 strains is a major goal of HIV-1 vaccine design. The challenge is that envelopes (Envs) of circulating viruses are almost certainly different from any Env used in a vaccine. A novel immunogen composed of a highly diverse set of gp140 Envs including subtypes A, B, C, D and F was developed to stimulate a more cross-neutralizing antibody response. Env heterotrimers composed of up to 54 different gp140s were produced with the aim of focusing the response to the conserved regions of Env while reducing the dominance of any individual hypervariable region. Heterotrimeric gp140 Envs of inter- and intra-subtype combinations were shown to bind CD4 and a panel of neutralizing monoclonal antibodies with similar affinity to monovalent UG37 gp140. Macaques immunized with six groups of heterotrimer mixtures showed slightly more potent neutralizing antibody responses in TZM-BL tier 1 and A3R5 tier 2 pseudovirus assays than macaques immunized with monovalent Env gp140, and exhibited a marginally greater focus on the CD4-binding site. Carbopol enhanced neutralization when used as an adjuvant instead of RIBI in combination with UG37 gp140. These data indicate that cross-subtype heterotrimeric gp140 Envs may elicit some improvement of the neutralizing antibody response in macaques compared to monovalent gp140 Env.
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Affiliation(s)
- Emma J. Bowles
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
- * E-mail: (EJB); (GSJ)
| | - Torben Schiffner
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Maximillian Rosario
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
| | - Gemma A. Needham
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Meghna Ramaswamy
- Division of Retrovirology, Centre for AIDS Reagents, National Institute of Biological Standards and Control, South Mimms, Potters Bar, Herts, United Kingdom
| | - Joanna McGouran
- Henry Wellcome Building for Molecular Physiology, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Benedikt Kessler
- Henry Wellcome Building for Molecular Physiology, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Celia LaBranche
- Division of Surgical Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Andrew J. McMichael
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
| | - David Montefiori
- Division of Surgical Sciences, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Quentin J. Sattentau
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Tomáš Hanke
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
- The Jenner Institute, University of Oxford, Old Road Campus Research Building, Oxford, United Kingdom
| | - Guillaume B. E. Stewart-Jones
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
- * E-mail: (EJB); (GSJ)
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17
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Abstract
Purpose of review To summarize the role of adjuvants in eliciting desirable antibody responses against HIV-1 with particular emphasis on both historical context and recent developments. Recent findings Increased understanding of the role of pattern recognition receptors such as Toll-like receptors in recruiting and directing the immune system has increased the variety of adjuvant formulations being tested in animal models and humans. Across all vaccine platforms, adjuvant formulations have been shown to enhance desirable immune responses such as higher antibody titers and increased functional activity. Although no vaccine formulation has yet succeeded in eliciting broad neutralizing antibodies against HIV-1, the ability of adjuvants to direct the immune response to immunogens suggests they will be critically important in any successful HIV-1 vaccine. Summary The parallel development of adjuvants along with better HIV-1 immunogens will be needed for a successful AIDS vaccine. Additional comparative testing will be required to determine the optimal adjuvant and immunogen regimen that can elicit antibody responses capable of blocking HIV-1 transmission.
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18
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Envelope variants circulating as initial neutralization breadth developed in two HIV-infected subjects stimulate multiclade neutralizing antibodies in rabbits. J Virol 2014; 88:12949-67. [PMID: 25210191 DOI: 10.1128/jvi.01812-14] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
UNLABELLED Identifying characteristics of the human immunodeficiency virus type 1 (HIV-1) envelope that are effective in generating broad, protective antibodies remains a hurdle to HIV vaccine design. Emerging evidence of the development of broad and potent neutralizing antibodies in HIV-infected subjects suggests that founder and subsequent progeny viruses may express unique antigenic motifs that contribute to this developmental pathway. We hypothesize that over the course of natural infection, B cells are programmed to develop broad antibodies by exposure to select populations of emerging envelope quasispecies variants. To test this hypothesis, we identified two unrelated subjects whose antibodies demonstrated increasing neutralization breadth against a panel of HIV-1 isolates over time. Full-length functional env genes were cloned longitudinally from these subjects from months after infection through 2.6 to 5.8 years of infection. Motifs associated with the development of breadth in published, cross-sectional studies were found in both subjects. We compared the immunogenicity of envelope vaccines derived from time points obtained during and after broadening of neutralization activity within these subjects. Rabbits were coimmunized four times with selected multiple gp160 DNAs and gp140-trimeric envelope proteins. The affinity of the polyclonal response increased as a function of boosting. The most rapid and persistent neutralization of multiclade tier 1 viruses was elicited by envelopes that were circulating in plasma at time points prior to the development of 50% neutralization breadth in both human subjects. The breadth elicited in rabbits was not improved by exposure to later envelope variants. These data have implications for vaccine development in describing a target time point to identify optimal envelope immunogens. IMPORTANCE Vaccine protection against viral infections correlates with the presence of neutralizing antibodies; thus, vaccine components capable of generating potent neutralization are likely to be critical constituents in an effective HIV vaccine. However, vaccines tested thus far have elicited only weak antibody responses and very modest, waning protection. We hypothesized that B cells develop broad antibodies by exposure to the evolving viral envelope population and tested this concept using multiple envelopes from two subjects who developed neutralization breadth within a few years of infection. We compared different combinations of envelopes from each subject to identify the most effective immunogens and regimens. In each subject, use of HIV envelopes circulating during the early development and maturation of breadth generated more-potent antibodies that were modestly cross neutralizing. These data suggest a new approach to identifying envelope immunogens that may be more effective in generating protective antibodies in humans.
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Abstract
PURPOSE OF REVIEW The HIV-1 site of binding for the CD4 receptor has long attracted attention as a potential supersite of vulnerability to antibody-mediated neutralization. We review recent findings related to effective CD4-binding site antibodies isolated from HIV-1-infected individuals and discuss implications for immunogen design. RECENT FINDINGS Highly effective CD4-binding site antibodies such as antibody VRC01 have the ability to neutralize over 90% of circulating HIV-1 strains. Sequence and structural analysis of these antibodies from over half a dozen HIV-1-infected donors reveals remarkable similarity in their ontogenies and their modes of recognition, all of which involve mimicry of CD4 receptor by antibody-heavy chain. Meanwhile, other effective CD4-binding site neutralizers such as antibody CH103 have been shown to utilize a different mode of recognition, with next-generation sequencing of both virus and antibody suggesting co-evolution to drive the development of antibody-neutralization breadth. SUMMARY The nexus of information concerning the CD4-binding site and its recognition by human antibodies capable of effective neutralization has expanded remarkably in the last few years. Although barriers are substantial, new insights from donor-serum responses, atomic-level structures of antibody-Env complexes, and next-generation sequencing of B-cell transcripts are invigorating vaccine-design efforts to elicit effective CD4-binding site antibodies.
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Pissani F, Malherbe DC, Schuman JT, Robins H, Park BS, Krebs SJ, Barnett SW, Haigwood NL. Improvement of antibody responses by HIV envelope DNA and protein co-immunization. Vaccine 2013; 32:507-13. [PMID: 24280279 DOI: 10.1016/j.vaccine.2013.11.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 10/29/2013] [Accepted: 11/06/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Developing HIV envelope (Env) vaccine components that elicit durable and protective antibody responses is an urgent priority, given the results from the RV144 trial. Optimization of both the immunogens and vaccination strategies will be needed to generate potent, durable antibodies. Due to the diversity of HIV, an effective Env-based vaccine will most likely require an extensive coverage of antigenic variants. A vaccine co-delivering Env immunogens as DNA and protein components could provide such coverage. Here, we examine a DNA and protein co-immunization strategy by characterizing the antibody responses and evaluating the relative contribution of each vaccine component. METHOD We co-immunized rabbits with representative subtype A or B HIV gp160 plasmid DNA plus Env gp140 trimeric glycoprotein and compared the responses to those obtained with either glycoprotein alone or glycoprotein in combination with empty vector. RESULTS DNA and glycoprotein co-immunization was superior to immunization with glycoprotein alone by enhancing antibody kinetics, magnitude, avidity, and neutralizing potency. Importantly, the empty DNA vector did not contribute to these responses. Humoral responses elicited by mismatched DNA and protein components were comparable or higher than the responses produced by the matched vaccines. CONCLUSION Our data show that co-delivering DNA and protein can augment antibodies to Env. The rate and magnitude of immune responses suggest that this approach has the potential to streamline vaccine regimens by inducing higher antibody responses using fewer vaccinations, an advantage for a successful HIV vaccine design.
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Affiliation(s)
- Franco Pissani
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, OR 97217, United States; The Vaccine and Gene Therapy Institute, Beaverton, OR 97006, United States; Oregon National Primate Research Center, Beaverton, OR 97006, United States
| | | | - Jason T Schuman
- GE Healthcare, Life Sciences, Piscataway, NJ 08854, United States
| | - Harlan Robins
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, United States
| | - Byung S Park
- Oregon National Primate Research Center, Beaverton, OR 97006, United States; Department of Public Health and Preventive Medicine, Oregon Health & Science University, Portland, OR 97239, United States
| | - Shelly J Krebs
- The Vaccine and Gene Therapy Institute, Beaverton, OR 97006, United States; Oregon National Primate Research Center, Beaverton, OR 97006, United States
| | - Susan W Barnett
- Novartis Institutes for Biomedical Research, Cambridge, MA 02139, United States
| | - Nancy L Haigwood
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, OR 97217, United States; The Vaccine and Gene Therapy Institute, Beaverton, OR 97006, United States; Oregon National Primate Research Center, Beaverton, OR 97006, United States.
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Robust neutralizing antibodies elicited by HIV-1 JRFL envelope glycoprotein trimers in nonhuman primates. J Virol 2013; 87:13239-51. [PMID: 24067980 DOI: 10.1128/jvi.01247-13] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Host cell-mediated proteolytic cleavage of the human immunodeficiency virus type 1 (HIV-1) gp160 precursor glycoprotein into gp120 and gp41 subunits is required to generate fusion-competent envelope glycoprotein (Env) spikes. The gp120-directed broadly neutralizing monoclonal antibodies (bNabs) isolated from HIV-infected individuals efficiently recognize fully cleaved JRFL Env spikes; however, nonneutralizing gp120-directed monoclonal antibodies isolated from infected or vaccinated subjects recognize only uncleaved JRFL spikes. Therefore, as an immunogen, cleaved spikes that selectively present desired neutralizing epitopes to B cells may elicit cross-reactive neutralizing antibodies. Accordingly, we inoculated nonhuman primates (NHPs) with plasmid DNA encoding transmembrane-anchored, cleaved JRFL Env or by electroporation (EP). Priming with DNA expressing soluble, uncleaved gp140 trimers was included as a comparative experimental group of NHPs. DNA inoculation was followed by boosts with soluble JRFL gp140 trimers, and control NHPs were inoculated with soluble JRFL protein trimers without DNA priming. In the TZM-bl assay, elicitation of neutralizing antibodies against HIV-1 tier 1 isolates was robust following the protein boost. Neutralization of tier 2 isolates was detected, but only in animals primed with plasmid DNA and boosted with trimeric protein. Using the more sensitive A3R5 assay, consistent neutralization of both clade B and C tier 2 isolates was detected from all regimens assessed in the current study, exceeding levels achieved by our previous vaccine regimens in primates. Together, these data suggest a potential advantage of B cell priming followed by a rest interval and protein boosting to present JRFL Env spikes to the immune system to better generate HIV-1 cross-clade neutralizing antibodies.
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Abstract
The development of an effective vaccine has been hindered by the enormous diversity of human immunodeficiency virus-1 (HIV-1) and its ability to escape a myriad of host immune responses. In addition, conserved vulnerable regions on the HIV-1 envelope glycoprotein are often poorly immunogenic and elicit broadly neutralizing antibody responses (BNAbs) in a minority of HIV-1-infected individuals and only after several years of infection. All of the known BNAbs demonstrate high levels of somatic mutations and often display other unusual traits, such as a long heavy chain complementarity determining region 3 (CDRH3) and autoreactivity that can be limited by host tolerance controls. Nonetheless, the demonstration that HIV-1-infected individuals can make potent BNAbs is encouraging, and recent progress in isolating such antibodies and mapping their immune pathways of development is providing new strategies for vaccination.
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Affiliation(s)
- John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA.
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Center RJ, Miller A, Wheatley AK, Campbell SM, Siebentritt C, Purcell DFJ. Utility of the Sindbis replicon system as an Env-targeted HIV vaccine. Vaccine 2013; 31:2260-6. [PMID: 23499600 DOI: 10.1016/j.vaccine.2013.02.064] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 02/20/2013] [Accepted: 02/28/2013] [Indexed: 02/06/2023]
Abstract
Sindbis replicon-based vaccine vectors are designed to combine the immunostimulatory properties of replicating viruses with the superior safety profile of non-replicating systems. In this study we performed a detailed assessment of Sindbis (SIN) replicon vectors expressing HIV-1 envelope protein (Env) for the induction of cell-mediated and humoral immune responses in a small animal model. SIN-derived virus-like particles (VLP) elicited Env-specific antibody responses that were detectable after boosting with recombinant Env protein. This priming effect could be mediated by replicon activity alone but may be enhanced by Env attached to the surface of VLP, offering a potential advantage for this mode of replicon delivery for Env based vaccination strategies. In contrast, the Env-specific CTL responses that were elicited by SIN-VLP were entirely dependent on replicon activity. SIN-VLP priming induced more durable humoral responses than immunization with protein only. This is important from a vaccine perspective, given the intrinsic tendency of Env to induce short-lived antibody responses in the context of vaccination or infection. These results indicate that further efforts to enhance the magnitude and durability of the HIV-1 Env-specific immune responses generated by Sindbis vectors, either alone or as part of prime-boost regimens, are justified.
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Affiliation(s)
- Rob J Center
- Department of Microbiology and Immunology, University of Melbourne, Australia
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24
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Abstract
Most neutralizing antibodies act at the earliest steps of viral infection and block interaction of the virus with cellular receptors to prevent entry into host cells. The inability to induce neutralizing antibodies to HIV has been a major obstacle to HIV vaccine research since the early days of the epidemic. However, in the past three years, the definition of a neutralizing antibody against HIV has been revolutionized by the isolation of extremely broad and potent neutralizing antibodies from HIV-infected individuals. Considerable hurdles remain for inducing neutralizing antibodies to a protective level after immunization. Meanwhile, novel technologies to bypass the induction of antibodies are being explored to provide prophylactic antibody-based interventions. This review addresses the challenge of inducing HIV neutralizing antibodies upon immunization and considers notable recent advances in the field. A greater understanding of the successes and failures for inducing a neutralizing response upon immunization is required to accelerate the development of an effective HIV vaccine.
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Affiliation(s)
- Laura E McCoy
- Wohl Virion Centre, Division of Infection and Immunity, University College London, London WC1E 6BT, England, UK
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25
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Brown EP, Licht AF, Dugast AS, Choi I, Bailey-Kellogg C, Alter G, Ackerman ME. High-throughput, multiplexed IgG subclassing of antigen-specific antibodies from clinical samples. J Immunol Methods 2012; 386:117-23. [PMID: 23023091 DOI: 10.1016/j.jim.2012.09.007] [Citation(s) in RCA: 173] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 09/18/2012] [Accepted: 09/19/2012] [Indexed: 11/27/2022]
Abstract
In vivo, the activity of antibodies relies critically on properties of both the variable domain, responsible for antigen recognition, and the constant domain, responsible for innate immune recognition. Here, we describe a flexible, microsphere-based array format for capturing information about both functional ends of disease-specific antibodies from complex, polyclonal clinical serum samples. Using minimal serum, we demonstrate IgG subclass profiling of multiple antibody specificities. We further capture and determine the subclass of epitope-specific antibodies. The data generated in this array provides a profile of the humoral immune response with multi-dimensional metrics regarding properties of both variable and constant IgG domains. Significantly, these properties are assessed simultaneously, and therefore information about the relationship between variable and constant domain characteristics is captured, and can be used to predict functions such as antibody effector activity.
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Affiliation(s)
- Eric P Brown
- Thayer School of Engineering, Dartmouth College, 14 Engineering Dr, Hanover, NH 03755, USA
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26
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Dosenovic P, Soldemo M, Scholz JL, O’Dell S, Grasset EK, Pelletier N, Karlsson MCI, Mascola JR, Wyatt RT, Cancro MP, Karlsson Hedestam GB. BLyS-mediated modulation of naive B cell subsets impacts HIV Env-induced antibody responses. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2012; 188:6018-26. [PMID: 22561155 PMCID: PMC3370119 DOI: 10.4049/jimmunol.1200466] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Neutralizing Abs provide the protective effect of the majority of existing human vaccines. For a prophylactic vaccine against HIV-1, broadly neutralizing Abs targeting conserved epitopes of the viral envelope glycoproteins (Env) are likely required, because the pool of circulating HIV-1 variants is extremely diverse. The failure to efficiently induce broadly neutralizing Abs by vaccination may be due to the use of suboptimal immunogens or immunization regimens, or it may indicate that B cells specific for broadly neutralizing Env determinants are selected against during peripheral checkpoints, either before or after Ag encounter. To investigate whether perturbation of B cell subsets prior to immunization with recombinant Env protein affects the vaccine-induced Ab response in mice, we used B lymphocyte stimulator (BLyS), a cytokine that regulates survival and selection of peripheral B cells. We show that the transient BLyS treatment used in this study substantially affected naive B cell populations; in particular, it resulted in more B cells surviving counter-selection at the transitional stages. We also observed more mature naive B cells, especially marginal zone B cells, in BLyS-treated mice. Intriguingly, provision of excess BLyS prior to immunization led to a consistent improvement in the frequency and potency of HIV-1 Env vaccine-induced neutralizing Ab responses, without increasing the number of Env-specific Ab-secreting cells or the Ab-binding titers measured after boosting. The results presented in this article suggest that an increased understanding of BLyS-regulated processes may help the design of vaccine regimens aimed at eliciting improved neutralizing Ab responses against HIV-1.
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Affiliation(s)
- Pia Dosenovic
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Martina Soldemo
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Jean L. Scholz
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Sijy O’Dell
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | | | - Nadège Pelletier
- Department of Immunology and Microbial Science, IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | | | - John R. Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Richard T. Wyatt
- Department of Immunology and Microbial Science, IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Michael P. Cancro
- University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
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Huang X, Jin W, Hu K, Luo S, Du T, Griffin GE, Shattock RJ, Hu Q. Highly conserved HIV-1 gp120 glycans proximal to CD4-binding region affect viral infectivity and neutralizing antibody induction. Virology 2012; 423:97-106. [DOI: 10.1016/j.virol.2011.11.023] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2011] [Revised: 11/15/2011] [Accepted: 11/28/2011] [Indexed: 10/14/2022]
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Feng Y, McKee K, Tran K, O'Dell S, Schmidt SD, Phogat A, Forsell MN, Karlsson Hedestam GB, Mascola JR, Wyatt RT. Biochemically defined HIV-1 envelope glycoprotein variant immunogens display differential binding and neutralizing specificities to the CD4-binding site. J Biol Chem 2011; 287:5673-86. [PMID: 22167180 DOI: 10.1074/jbc.m111.317776] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
HIV-1 gp120 binds the primary receptor CD4. Recently, a plethora of broadly neutralizing antibodies to the gp120 CD4-binding site (CD4bs) validated this region as a target for immunogen design. Here, we asked if modified HIV-1 envelope glycoproteins (Env) designed to increase CD4 recognition might improve recognition by CD4bs neutralizing antibodies and more efficiently elicit such reactivities. We also asked if CD4bs stabilization, coupled with altering the Env format (monomer to trimer or cross-clade), might better elicit neutralizing antibodies by focusing the immune response on the functionally conserved CD4bs. We produced monomeric and trimeric Envs stabilized by mutations within the gp120 CD4bs cavity (pocket-filling; PF2) or by appending heterologous trimerization motifs to soluble Env ectodomains (gp120/gp140). Recombinant glycoproteins were purified to relative homogeneity, and ligand binding properties were analyzed by ELISA, surface plasmon resonance, and isothermal titration microcalorimetry. In some formats, the PF2 substitutions increased CD4 affinity, and importantly, PF2-containing proteins were better recognized by the broadly neutralizing CD4bs mAbs, VRC01 and VRC-PG04. Based on this analysis, we immunized selected Env variants into rabbits using heterologous or homologous regimens. Analysis of the sera revealed that homologous inoculation of the PF2-containing, variable region-deleted YU2 gp120 trimers (ΔV123/PF2-GCN4) more rapidly elicited CD4bs-directed neutralizing antibodies compared with other regimens, whereas homologous trimers elicited increased neutralization potency, mapping predominantly to the gp120 third major variable region (V3). These results suggest that some engineered Env proteins may more efficiently direct responses toward the conserved CD4bs and be valuable to elicit antibodies of greater neutralizing capacity.
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Affiliation(s)
- Yu Feng
- IAVI Neutralizing Antibody Center, Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California 92037, USA
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Cross-clade HIV-1 neutralizing antibodies induced with V3-scaffold protein immunogens following priming with gp120 DNA. J Virol 2011; 85:9887-98. [PMID: 21795338 DOI: 10.1128/jvi.05086-11] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The V3 epitope is a known target for HIV-1 neutralizing antibodies (NAbs), and V3-scaffold fusion proteins used as boosting immunogens after gp120 DNA priming were previously shown to induce NAbs in rabbits. Here, we evaluated whether the breadth and potency of the NAb response could be improved when boosted with rationally designed V3-scaffold immunogens. Rabbits were primed with codon-optimized clade C gp120 DNA and boosted with one of five V3-cholera toxin B fusion proteins (V3-CTBs) or with double combinations of these. The inserts in these immunogens were designed to display V3 epitopes shared by the majority of global HIV-1 isolates. Double combinations of V3-CTB immunogens generally induced more broad and potent NAbs than did boosts with single V3-CTB immunogens, with the most potent and broad NAbs elicited with the V3-CTB carrying the consensus V3 of clade C (V3(C)-CTB), or with double combinations of V3-CTB immunogens that included V3(C)-CTB. Neutralization of tier 1 and 2 pseudoviruses from clades AG, B, and C and of peripheral blood mononuclear cell (PBMC)-grown primary viruses from clades A, AG, and B was achieved, demonstrating that priming with gp120 DNA followed by boosts with V3-scaffold immunogens effectively elicits cross-clade NAbs. Focusing on the V3 region is a first step in designing a vaccine targeting protective epitopes, a strategy with potential advantages over the use of Env, a molecule that evolved to protect the virus by poorly inducing NAbs and by shielding the epitopes that are most critical for infectivity.
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30
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Du SX, Xu L, Zhang W, Tang S, Boenig RI, Chen H, Mariano EB, Zwick MB, Parren PWHI, Burton DR, Wrin T, Petropoulos CJ, Ballantyne JA, Chambers M, Whalen RG. A directed molecular evolution approach to improved immunogenicity of the HIV-1 envelope glycoprotein. PLoS One 2011; 6:e20927. [PMID: 21738594 PMCID: PMC3126809 DOI: 10.1371/journal.pone.0020927] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Accepted: 05/12/2011] [Indexed: 12/14/2022] Open
Abstract
A prophylactic vaccine is needed to slow the spread of HIV-1 infection. Optimization of the wild-type envelope glycoproteins to create immunogens that can elicit effective neutralizing antibodies is a high priority. Starting with ten genes encoding subtype B HIV-1 gp120 envelope glycoproteins and using in vitro homologous DNA recombination, we created chimeric gp120 variants that were screened for their ability to bind neutralizing monoclonal antibodies. Hundreds of variants were identified with novel antigenic phenotypes that exhibit considerable sequence diversity. Immunization of rabbits with these gp120 variants demonstrated that the majority can induce neutralizing antibodies to HIV-1. One novel variant, called ST-008, induced significantly improved neutralizing antibody responses when assayed against a large panel of primary HIV-1 isolates. Further study of various deletion constructs of ST-008 showed that the enhanced immunogenicity results from a combination of effective DNA priming, an enhanced V3-based response, and an improved response to the constant backbone sequences.
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Affiliation(s)
- Sean X. Du
- Department of Infectious Diseases, Maxygen, Inc., Redwood City, California, United States of America
| | - Li Xu
- Department of Infectious Diseases, Maxygen, Inc., Redwood City, California, United States of America
| | - Wenge Zhang
- Department of Infectious Diseases, Maxygen, Inc., Redwood City, California, United States of America
| | - Susan Tang
- Department of Infectious Diseases, Maxygen, Inc., Redwood City, California, United States of America
| | - Rebecca I. Boenig
- Department of Infectious Diseases, Maxygen, Inc., Redwood City, California, United States of America
| | - Helen Chen
- Department of Infectious Diseases, Maxygen, Inc., Redwood City, California, United States of America
| | - Ellaine B. Mariano
- Department of Infectious Diseases, Maxygen, Inc., Redwood City, California, United States of America
| | - Michael B. Zwick
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Paul W. H. I. Parren
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, United States of America
| | - Dennis R. Burton
- Department of Immunology and Microbial Science, and IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California, United States of America
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard, Boston, Massachusetts, United States of America
| | - Terri Wrin
- Monogram Biosciences, San Francisco, California, United States of America
| | | | | | | | - Robert G. Whalen
- Department of Infectious Diseases, Maxygen, Inc., Redwood City, California, United States of America
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Binding interactions between soluble HIV envelope glycoproteins and quaternary-structure-specific monoclonal antibodies PG9 and PG16. J Virol 2011; 85:7095-107. [PMID: 21543501 DOI: 10.1128/jvi.00411-11] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PG9 and PG16 are antibodies isolated from a subject infected with HIV-1 and display broad anti-HIV neutralizing activities. They recognize overlapping epitopes, which are preferentially expressed on the membrane-anchored trimeric form of the HIV envelope glycoprotein (Env). PG9 and PG16 were reported not to bind to soluble mimetics of Env. The engineering of soluble Env proteins on which the PG9 and PG16 epitopes are optimally exposed will support efforts to elicit broad anti-HIV neutralizing antibodies by immunization. Here, we identified several soluble gp140 Env proteins that are recognized by PG9 and PG16, and we investigated the molecular details of those binding interactions. The IgG versions of PG9 and PG16 recognize the soluble trimeric gp140 form less efficiently than the corresponding monomeric gp140 form. In contrast, the Fab versions of PG9 and PG16 recognized the monomeric and trimeric gp140 forms with identical binding kinetics and with binding affinities similar to the high binding affinity of the anti-V3 antibody 447D to its epitope. Our data also indicate that, depending on the Env backbone, the interactions of PG9 and PG16 with gp140 may be facilitated by the presence of the gp41 ectodomain and are independent of the proper enzymatic cleavage of gp140 into gp120 and gp41. The identification of soluble Env proteins that express the PG9 and PG16 epitopes and the detailed characterization of the molecular interactions between these two antibodies and their ligands provide important and novel information that will assist in improving the engineering of future Env immunogens.
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Immunization with recombinant HLA classes I and II, HIV-1 gp140, and SIV p27 elicits protection against heterologous SHIV infection in rhesus macaques. J Virol 2011; 85:6442-52. [PMID: 21490092 DOI: 10.1128/jvi.00129-11] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Major histocompatibility complex (MHC) molecules expressed on the surface of human immunodeficiency virus (HIV) are potential targets for neutralizing antibodies. Since MHC molecules are polymorphic, nonself MHC can also be immunogenic. We have used combinations of novel recombinant HLA class I and II and HIV/simian immunodeficiency virus (SIV) antigens, all linked to dextran, to investigate whether they can elicit protective immunity against heterologous simian/human immunodeficiency virus (SHIV) challenge in rhesus macaques. Three groups of animals were immunized with HLA (group 1, n = 8), trimeric YU2 HIV type 1 (HIV-1) gp140 and SIV p27 (HIV/SIV antigens; group 2, n = 8), or HLA plus HIV/SIV antigens (group 3, n = 8), all with Hsp70 and TiterMax Gold adjuvant. Another group (group 4, n = 6) received the same vaccine as group 3 without TiterMax Gold. Two of eight macaques in group 3 were completely protected against intravenous challenge with 18 50% animal infective doses (AID(50)) of SHIV-SF162P4/C grown in human cells expressing HLA class I and II lineages represented in the vaccine, while the remaining six macaques showed decreased viral loads compared to those in unimmunized animals. Complement-dependent neutralizing activity in serum and high levels of anti-HLA antibodies were elicited in groups 1 and 3, and both were inversely correlated with the plasma viral load at 2 weeks postchallenge. Antibody-mediated protection was strongly supported by the fact that transfer of pooled serum from the two challenged but uninfected animals protected two naïve animals against repeated low-dose challenge with the same SHIV stock. This study demonstrates that immunization with recombinant HLA in combination with HIV-1 antigens might be developed into an alternative strategy for a future AIDS vaccine.
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Immunization with HIV Gag targeted to dendritic cells followed by recombinant New York vaccinia virus induces robust T-cell immunity in nonhuman primates. Proc Natl Acad Sci U S A 2011; 108:7131-6. [PMID: 21467219 DOI: 10.1073/pnas.1103869108] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Protein vaccines, if rendered immunogenic, would facilitate vaccine development against HIV and other pathogens. We compared in nonhuman primates (NHPs) immune responses to HIV Gag p24 within 3G9 antibody to DEC205 ("DEC-HIV Gag p24"), an uptake receptor on dendritic cells, to nontargeted protein, with or without poly ICLC, a synthetic double stranded RNA, as adjuvant. Priming s.c. with 60 μg of both HIV Gag p24 vaccines elicited potent CD4(+) T cells secreting IL-2, IFN-γ, and TNF-α, which also proliferated. The responses increased with each of three immunizations and recognized multiple Gag peptides. DEC-HIV Gag p24 showed better cross-priming for CD8(+) T cells, whereas the avidity of anti-Gag antibodies was ∼10-fold higher with nontargeted Gag 24 protein. For both protein vaccines, poly ICLC was essential for T- and B-cell immunity. To determine whether adaptive responses could be further enhanced, animals were boosted with New York vaccinia virus (NYVAC)-HIV Gag/Pol/Nef. Gag-specific CD4(+) and CD8(+) T-cell responses increased markedly after priming with both protein vaccines and poly ICLC. These data reveal qualitative differences in antibody and T-cell responses to DEC-HIV Gag p24 and Gag p24 protein and show that prime boost with protein and adjuvant followed by NYVAC elicits potent cellular immunity.
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Da LT, Quan JM, Wu YD. Understanding the binding mode and function of BMS-488043 against HIV-1 viral entry. Proteins 2011; 79:1810-9. [DOI: 10.1002/prot.23005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2010] [Revised: 01/10/2011] [Accepted: 01/20/2011] [Indexed: 11/08/2022]
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Kim JH, Park JS, Yang HN, Woo DG, Jeon SY, Do HJ, Lim HY, Kim JM, Park KH. The use of biodegradable PLGA nanoparticles to mediate SOX9 gene delivery in human mesenchymal stem cells (hMSCs) and induce chondrogenesis. Biomaterials 2010; 32:268-78. [PMID: 20875683 DOI: 10.1016/j.biomaterials.2010.08.086] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2010] [Accepted: 08/27/2010] [Indexed: 12/16/2022]
Abstract
In stem cell therapy, transfection of specific genes into stem cells is an important technique to induce cell differentiation. To perform gene transfection in human mesenchymal stem cells (hMSCs), we designed and fabricated a non-viral vector system for specific stem cell differentiation. Several kinds of gene carriers were evaluated with regard to their transfection efficiency and their ability to enhance hMSCs differentiation. Of these delivery vehicles, biodegradable poly (DL-lactic-co-glycolic acid) (PLGA) nanoparticles yielded the best results, as they complexed with high levels of plasmid DNA (pDNA), allowed robust gene expression in hMSCs, and induced chondrogenesis. Polyplexing with polyethylenimine (PEI) enhanced the cellular uptake of SOX9 DNA complexed with PLGA nanoparticles both in vitro and in vivo. The expression of enhanced green fluorescent protein (EGFP) and SOX9 increased up to 75% in hMSCs transfected with PEI/SOX9 complexed PLGA nanoparticles 2 days after transfection. SOX9 gene expression was evaluated by RT-PCR, real time-qPCR, glycosaminoglycan (GAG)/DNA levels, immunoblotting, histology, and immunofluorescence.
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Affiliation(s)
- Jae-Hwan Kim
- Department of Biomedical Science, College of Life Science, CHA University 606-16, Yeoksam 1-Dong, Kangnam-gu, Seoul 135-081, Republic of Korea
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Walker LM, Simek MD, Priddy F, Gach JS, Wagner D, Zwick MB, Phogat SK, Poignard P, Burton DR. A limited number of antibody specificities mediate broad and potent serum neutralization in selected HIV-1 infected individuals. PLoS Pathog 2010; 6:e1001028. [PMID: 20700449 PMCID: PMC2916884 DOI: 10.1371/journal.ppat.1001028] [Citation(s) in RCA: 293] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Accepted: 07/01/2010] [Indexed: 11/19/2022] Open
Abstract
A protective vaccine against HIV-1 will likely require the elicitation of a broadly neutralizing antibody (bNAb) response. Although the development of an immunogen that elicits such antibodies remains elusive, a proportion of HIV-1 infected individuals evolve broadly neutralizing serum responses over time, demonstrating that the human immune system can recognize and generate NAbs to conserved epitopes on the virus. Understanding the specificities that mediate broad neutralization will provide insight into which epitopes should be targeted for immunogen design and aid in the isolation of broadly neutralizing monoclonal antibodies from these donors. Here, we have used a number of new and established technologies to map the bNAb specificities in the sera of 19 donors who exhibit among the most potent cross-clade serum neutralizing activities observed to date. The results suggest that broad and potent serum neutralization arises in most donors through a limited number of specificities (1-2 per donor). The major targets recognized are an epitope defined by the bNAbs PG9 and PG16 that is associated with conserved regions of the V1, V2 and V3 loops, an epitope overlapping the CD4 binding site and possibly the coreceptor binding site, an epitope sensitive to a loss of the glycan at N332 and distinct from that recognized by the bNAb 2G12 and an epitope sensitive to an I165A substitution. In approximately half of the donors, key N-linked glycans were critical for expression of the epitopes recognized by the bNAb specificities in the sera.
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Affiliation(s)
- Laura M. Walker
- Department of Immunology and Microbial Science and IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California, United States of America
| | - Melissa D. Simek
- International AIDS Vaccine Initiative, New York, New York, United States of America
| | - Frances Priddy
- International AIDS Vaccine Initiative, New York, New York, United States of America
| | - Johannes S. Gach
- Department of Immunology and Microbial Science and IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California, United States of America
| | - Denise Wagner
- IAVI AIDS Vaccine Design and Development Laboratory, Brooklyn, New York, United States of America
| | - Michael B. Zwick
- Department of Immunology and Microbial Science and IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California, United States of America
| | - Sanjay K. Phogat
- IAVI AIDS Vaccine Design and Development Laboratory, Brooklyn, New York, United States of America
| | - Pascal Poignard
- Department of Immunology and Microbial Science and IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California, United States of America
| | - Dennis R. Burton
- Department of Immunology and Microbial Science and IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California, United States of America
- Ragon Institute of MGH, MIT, and Harvard, Boston, Massachusetts, United States of America
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Pietzsch J, Scheid JF, Mouquet H, Klein F, Seaman MS, Jankovic M, Corti D, Lanzavecchia A, Nussenzweig MC. Human anti-HIV-neutralizing antibodies frequently target a conserved epitope essential for viral fitness. ACTA ACUST UNITED AC 2010; 207:1995-2002. [PMID: 20679402 PMCID: PMC2931156 DOI: 10.1084/jem.20101176] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The identification and characterization of conserved epitopes on the HIV-1 viral spike that are immunogenic in humans and targeted by neutralizing antibodies is an important step in vaccine design. Antibody cloning experiments revealed that 32% of all HIV-neutralizing antibodies expressed by the memory B cells in patients with high titers of broadly neutralizing antibodies recognize one or more “core” epitopes that were not defined. Here, we show that anti-core antibodies recognize a single conserved epitope on the gp120 subunit. Amino acids D474, M475, R476, which are essential for anti-core antibody binding, form an immunodominant triad at the outer domain/inner domain junction of gp120. The mutation of these residues to alanine impairs viral fusion and fitness. Thus, the core epitope, a frequent target of anti–HIV-neutralizing antibodies, including the broadly neutralizing antibody HJ16, is conserved and indispensible for viral infectivity. We conclude that the core epitope should be considered as a target for vaccine design.
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Affiliation(s)
- John Pietzsch
- Laboratory of Molecular Immunology and Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA
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Sundling C, Forsell MNE, O'Dell S, Feng Y, Chakrabarti B, Rao SS, Loré K, Mascola JR, Wyatt RT, Douagi I, Karlsson Hedestam GB. Soluble HIV-1 Env trimers in adjuvant elicit potent and diverse functional B cell responses in primates. ACTA ACUST UNITED AC 2010; 207:2003-17. [PMID: 20679401 PMCID: PMC2931166 DOI: 10.1084/jem.20100025] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Broadly neutralizing antibodies (bNAbs) against the HIV-1 envelope glycoproteins (Envs) have proven difficult to elicit by immunization. Therefore, to identify effective Env neutralization targets, efforts are underway to define the specificities of bNAbs in chronically infected individuals. For a prophylactic vaccine, it is equally important to define the immunogenic properties of the heavily glycosylated Env in healthy primates devoid of confounding HIV-induced pathogenic factors. We used rhesus macaques to investigate the magnitude and kinetics of B cell responses stimulated by Env trimers in adjuvant. Robust Env-specific memory B cell responses and high titers of circulating antibodies developed after trimer inoculation. Subsequent immunizations resulted in significant expansion of Env-specific IgG-producing plasma cell populations and circulating Abs that displayed increasing avidity and neutralization capacity. The neutralizing activity elicited with the regimen used was, in most aspects, superior to that elicited by a regimen based on monomeric Env immunization in humans. Despite the potency and breadth of the trimer-elicited response, protection against heterologous rectal simian-HIV (SHIV) challenge was modest, illustrating the challenge of eliciting sufficient titers of cross-reactive protective NAbs in mucosal sites. These data provide important information for the design and evaluation of vaccines aimed at stimulating protective HIV-1 immune responses in humans.
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Affiliation(s)
- Christopher Sundling
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
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Immunization with wild-type or CD4-binding-defective HIV-1 Env trimers reduces viremia equivalently following heterologous challenge with simian-human immunodeficiency virus. J Virol 2010; 84:9086-95. [PMID: 20610729 DOI: 10.1128/jvi.01015-10] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We recently reported that rhesus macaques inoculated with CD4-binding-competent and CD4-binding-defective soluble YU2-derived HIV-1 envelope glycoprotein (Env) trimers in adjuvant generate comparable levels of Env-specific binding antibodies (Abs) and T cell responses. We also showed that Abs directed against the Env coreceptor binding site (CoRbs) were elicited only in animals immunized with CD4-binding-competent trimers and not in animals immunized with CD4-binding-defective trimers, indicating that a direct interaction between Env and CD4 occurs in vivo. To investigate both the overall consequences of in vivo Env-CD4 interactions and the elicitation of CoRbs-directed Abs for protection against heterologous simian-human immunodeficiency virus (SHIV) challenge, we exposed rhesus macaques immunized with CD4-binding-competent and CD4-binding-defective trimers to the CCR5-tropic SHIV-SF162P4 challenge virus. Compared to unvaccinated controls, all vaccinated animals displayed improved control of plasma viremia, independent of the presence or absence of CoRbs-directed Abs prior to challenge. Immunization resulted in plasma responses that neutralized the heterologous SHIV challenge stock in vitro, with similar neutralizing Ab titers elicited by the CD4-binding-competent and CD4-binding-defective trimers. The neutralizing responses against both the SHIV-SF162P4 stock and a recombinant virus pseudotyped with a cloned SHIV-SF162P4-derived Env were significantly boosted by the SHIV challenge. Collectively, these results suggest that the capacity of soluble Env trimers to interact with primate CD4 in vivo and to stimulate the production of moderate titers of CoRbs-directed Abs did not influence the magnitude of the neutralizing Ab recall response after viral challenge or the subsequent control of viremia in this heterologous SHIV challenge model.
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Abstract
Licensed vaccines against viral diseases generate antibodies that neutralize the infecting virus and protect against infection or disease. Similarly, an effective vaccine against HIV-1 will likely need to induce antibodies that prevent initial infection of host cells or that limit early events of viral dissemination. Such antibodies must target the surface envelope glycoproteins of HIV-1, which are highly variable in sequence and structure. The first subunit vaccines to enter clinical trails were safe and immunogenic but unable to elicit antibodies that neutralized most circulating strains of HIV-1. However, potent virus neutralizing antibodies (NAbs) can develop during the course of HIV-1 infection, and this is the type of antibody response that researchers seek to generate with a vaccine. Thus, current vaccine design efforts have focused on a more detailed understanding of these broadly neutralizing antibodies and their epitopes to inform the design of improved vaccines.
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Affiliation(s)
- John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
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Abstract
PURPOSE OF REVIEW To summarize recent progress in the development of adjuvants with a special focus on adjuvants that enhance B-cell responses to protein-based vaccines. Both established and new experimental approaches are described and also briefly we discuss how adjuvants and virus-based vaccines interact with the immune system. RECENT FINDINGS Two new adjuvants were recently approved for human applications and many others are in preclinical or clinical testing. Significant advances were made to describe the mechanism of action of adjuvants. For example, aluminum hydroxide salts were shown to engage Nalp3, a member of the cytosolic NOD-like receptors and activation of B cells via invariant natural killer cell presentation of alpha-galactosylceramide was described. The effects of Toll-like receptor ligands on B-cell differentiation were further characterized and a peptide derived from IPS-1, a cytosolic signaling molecule, was shown to provide adjuvant effect. Stimulation of protective antibodies against HIV-1 may require extensive antibody affinity maturation, thus long-term exposure or repeated administration of antigen may be needed to induce effective B-cell responses. SUMMARY Advances in our understanding of how specific signaling pathways link innate and adaptive immunity provides a basis for the design of improved adjuvants to promote broad and potent B-cell responses.
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Abstract
PURPOSE OF REVIEW We summarize and discuss recent developments regarding the immunogenicity of human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) oligomers, focusing, for the most part, on trimeric, recombinant protein immunogens. RECENT FINDINGS The three-dimensional cryo-electron tomography images of the HIV-1 Env trimeric spike, coupled with previous data demonstrating the impact on envelope glycoprotein (gp120)-transmembrane glycoprotein (gp41) cleavage of the architecture of the Env trimers, provide exciting information that may lead to new avenues for novel immunogen design. Through new processes to map region-specific anti-Env antibodies present in immune serum, it is now possible to define antibody specificities against conformationally sensitive surfaces of Env. A number of strategies designed to counteract the immunodominance of the HIV-1 Env variable regions were attempted, and a recent study demonstrates that immunization with Env trimers provides sterilizing protection against mucosal challenge with virus. Importantly, protection against the challenge virus was associated with in-vitro HIV-1 neutralization titers. SUMMARY Several studies within the past 18 months provide exciting structural information and the development of tools that have the potential to improve Env trimer design and the analysis of trimer immunogenicity studies. The ability to predict protection against a challenge virus through an in-vitro neutralization screen may be very helpful for evaluation of immunogens to move forward into clinical trials.
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Env-expressing autologous T lymphocytes induce neutralizing antibody and afford marked protection against feline immunodeficiency virus. J Virol 2010; 84:3845-56. [PMID: 20130057 DOI: 10.1128/jvi.02638-09] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The envelope (Env) glycoproteins of HIV and other lentiviruses possess neutralization and other protective epitopes, yet all attempts to induce protective immunity using Env as the only immunogen have either failed or afforded minimal levels of protection. In a novel prime-boost approach, specific-pathogen-free cats were primed with a plasmid expressing Env of feline immunodeficiency virus (FIV) and feline granulocyte-macrophage colony-stimulating factor and then boosted with their own T lymphocytes transduced ex vivo to produce the same Env and interleukin 15 (3 x 10(6) to 10 x 10(6) viable cells/cat). After the boost, the vaccinees developed elevated immune responses, including virus-neutralizing antibodies (NA). Challenge with an ex vivo preparation of FIV readily infected all eight control cats (four mock vaccinated and four naïve) and produced a marked decline in the proportion of peripheral CD4 T cells. In contrast, five of seven vaccinees showed little or no traces of infection, and the remaining two had reduced viral loads and underwent no changes in proportions of CD4 T cells. Interestingly, the viral loads of the vaccinees were inversely correlated to the titers of NA. The findings support the concept that Env is a valuable immunogen but needs to be administered in a way that permits the expression of its full protective potential.
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Aarnink A, Estrade L, Apoil PA, Kita YF, Saitou N, Shiina T, Blancher A. Study of cynomolgus monkey (Macaca fascicularis) DRA polymorphism in four populations. Immunogenetics 2010; 62:123-36. [PMID: 20094710 DOI: 10.1007/s00251-009-0421-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2009] [Accepted: 12/21/2009] [Indexed: 12/11/2022]
Abstract
To describe the polymorphism of the DRA gene in Macaca fascicularis, we have studied 141 animals either at cDNA level (78 animals from Mauritius, the Philippines, and Vietnam) or genomic level (63 animals from the Philippines, Indonesia, and Vietnam). In total, we characterized 22 cDNA DRA alleles, 13 of which had not been described until now. In the Mauritius population, we confirmed the presence of three DRA alleles. In the Philippine and Vietnam populations, we observed 11 and 14 DRA alleles, respectively. Only two alleles were present in all three populations. All DRA alleles but one differ from the consensus sequence by one to three mutations, most being synonymous; so, only seven DR alpha proteins were deduced from the 22 cDNA alleles. One DRA cDNA allele, Mafa-DRA*02010101, differs from all other alleles by 11 to 14 mutations of which only four are non-synonymous. The two amino acid changes inside the peptide groove of Mafa-DRA*02010101 are highly conservative. The very low proportion of non-synonymous/synonymous mutations is compatible with a purifying selection which is comparable to all previous observations concerning the evolution of the DRA gene in mammals. Homologues of the allele Mafa-DRA*02010101 are also found in two other Asian macaques (Macaca mulatta and Macaca nemestrina). The forces able to maintain this highly divergent allele in three different macaque species remain hypothetical.
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Affiliation(s)
- Alice Aarnink
- Laboratoire d'immunogénétique moléculaire, EA3034, Faculté de Médecine Purpan, Toulouse 3, France
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Breadth of neutralizing antibodies elicited by stable, homogeneous clade A and clade C HIV-1 gp140 envelope trimers in guinea pigs. J Virol 2010; 84:3270-9. [PMID: 20053749 DOI: 10.1128/jvi.02252-09] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The native envelope (Env) spike on the surface of human immunodeficiency virus type 1 (HIV-1) is trimeric, and thus trimeric Env vaccine immunogens are currently being explored in preclinical immunogenicity studies. Key challenges have included the production and purification of biochemically homogeneous and stable trimers and the evaluation of these immunogens utilizing standardized virus panels for neutralization assays. Here we report the binding and neutralizing antibody (NAb) responses elicited by clade A (92UG037.8) and clade C (CZA97.012) Env gp140 trimer immunogens in guinea pigs. These trimers have been selected and engineered for optimal biochemical stability and have defined antigenic properties. Purified gp140 trimers with Ribi adjuvant elicited potent, cross-clade NAb responses against tier 1 viruses as well as detectable but low-titer NAb responses against select tier 2 viruses from clades A, B, and C. In particular, the clade C trimer elicited NAbs that neutralized 27%, 20%, and 47% of tier 2 viruses from clades A, B, and C, respectively. Heterologous DNA prime, protein boost as well as DNA prime, recombinant adenovirus boost regimens expressing these antigens, however, did not result in an increased magnitude or breadth of NAb responses in this system. These data demonstrate the immunogenicity of stable, homogeneous clade A and clade C gp140 trimers and exemplify the utility of standardized tier 1 and tier 2 virus panels for assessing the NAb responses of candidate HIV-1 Env immunogens.
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Willey R, Nason MC, Nishimura Y, Follmann DA, Martin MA. Neutralizing antibody titers conferring protection to macaques from a simian/human immunodeficiency virus challenge using the TZM-bl assay. AIDS Res Hum Retroviruses 2010; 26:89-98. [PMID: 20059398 DOI: 10.1089/aid.2009.0144] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We previously reported that passive transfer of polyclonal neutralizing antibodies (NAbs) sufficient to generate a titer of 1:38 in the plasma would confer sterilizing protection to 99% of macaques challenged intravenously with 75 TCID(50) of SHIV(DH12). Neutralizing activity in that study was measured in an MT4 cell assay in which infection was completely blocked (EC(100)). In the current study, the TZM-bl system was used to measure EC(50) neutralizing titers in several of the same macaque plasma samples and the relationship between these titers and in vivo protection was determined. The antiviral EC(50) NAb titers measured in individual plasma samples were higher than those previously obtained in the MT4 system. Furthermore, the geometric mean EC(50) NAb titers against pseudotyped SHIV(DH12) were 33-fold greater than the EC(100) titers measured in the MT4 cell assay against the replication-competent SHIV(DH12) inoculated into animals. An augmented probit regression model was used to generate curves relating TZM-bl EC(50) NAb titers and protection from a virus challenge; estimated titers conferring various levels of protection were then determined. In TZM-bl assays using pseudotyped SHIV(DH12), representative percent in vivo protection/estimated EC(50) titers were 99%/1:4467, 90%/1:1175, 80%/1:676, 50%/1:234, and 33%/1:141. Because it is likely that contributions from other arms of the immune system will contribute to vaccine-induced control, the range of EC(50) NAb titers we have derived may be more informative for evaluating the protective value of NAb activity from TZM-bl assays.
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Affiliation(s)
- Ronald Willey
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Martha C. Nason
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Yoshiaki Nishimura
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Dean A. Follmann
- Biostatistics Research Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
| | - Malcolm A. Martin
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892
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Influence of novel CD4 binding-defective HIV-1 envelope glycoprotein immunogens on neutralizing antibody and T-cell responses in nonhuman primates. J Virol 2009; 84:1683-95. [PMID: 19955308 DOI: 10.1128/jvi.01896-09] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The high-affinity in vivo interaction between soluble HIV-1 envelope glycoprotein (Env) immunogens and primate CD4 results in conformational changes that alter the immunogenicity of the gp120 subunit. Because the conserved binding site on gp120 that directly interacts with CD4 is a major vaccine target, we sought to better understand the impact of in vivo Env-CD4 interactions during vaccination. Rhesus macaques were immunized with soluble wild-type (WT) Env trimers, and two trimer immunogens rendered CD4 binding defective through distinct mechanisms. In one variant, we introduced a mutation that directly disrupts CD4 binding (368D/R). In the second variant, we introduced three mutations (423I/M, 425N/K, and 431G/E) that disrupt CD4 binding indirectly by altering a gp120 subdomain known as the bridging sheet, which is required for locking Env into a stable interaction with CD4. Following immunization, Env-specific binding antibody titers and frequencies of Env-specific memory B cells were comparable between the groups. However, the quality of neutralizing antibody responses induced by the variants was distinctly different. Antibodies against the coreceptor binding site were elicited by WT trimers but not the CD4 binding-defective trimers, while antibodies against the CD4 binding site were elicited by the WT and the 423I/M, 425N/K, and 431G/E trimers but not the 368D/R trimers. Furthermore, the CD4 binding-defective trimer variants stimulated less potent neutralizing antibody activity against neutralization-sensitive viruses than WT trimers. Overall, our studies do not reveal any potential negative effects imparted by the in vivo interaction between WT Env and primate CD4 on the generation of functional T cells and antibodies in response to soluble Env vaccination.
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Da LT, Quan JM, Wu YD. Understanding of the Bridging Sheet Formation of HIV-1 Glycoprotein gp120. J Phys Chem B 2009; 113:14536-43. [DOI: 10.1021/jp9081239] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lin-Tai Da
- Laboratory of Chemical Genomics, Shenzhen Graduate School of Peking University, Shenzhen 518055, China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Jun-Min Quan
- Laboratory of Chemical Genomics, Shenzhen Graduate School of Peking University, Shenzhen 518055, China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Yun-Dong Wu
- Laboratory of Chemical Genomics, Shenzhen Graduate School of Peking University, Shenzhen 518055, China, and Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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Dosenovic P, Chakrabarti B, Soldemo M, Douagi I, Forsell MNE, Li Y, Phogat A, Paulie S, Hoxie J, Wyatt RT, Karlsson Hedestam GB. Selective expansion of HIV-1 envelope glycoprotein-specific B cell subsets recognizing distinct structural elements following immunization. THE JOURNAL OF IMMUNOLOGY 2009; 183:3373-82. [PMID: 19696434 DOI: 10.4049/jimmunol.0900407] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The HIV-1 envelope glycoprotein (Env) functional spike has evolved multiple immune evasion strategies, and only a few broadly neutralizing determinants on the assembled spike are accessible to Abs. Serological studies, based upon Ab binding and neutralization activity in vitro, suggest that vaccination with current Env-based immunogens predominantly elicits Abs that bind nonneutralizing or strain-restricted neutralizing epitopes. However, the fractional specificities of the polyclonal mixture of Abs present in serum, especially those directed to conformational Env epitopes, are often difficult to determine. Furthermore, serological analyses do not provide information regarding how repeated Ag inoculation impacts the expansion and maintenance of Env-specific B cell subpopulations. Therefore, we developed a highly sensitive Env-specific B cell ELISPOT system, which allows the enumeration of Ab-secreting cells (ASC) from diverse anatomical compartments directed against different structural determinants of Env. In this study, we use this system to examine the evolution of B cell responses in mice immunized with engineered Env trimers in adjuvant. We demonstrate that the relative proportion of ASC specific for defined structural elements of Env is altered significantly by homologous booster immunizations. This results in the selective expansion of ASC directed against the variable regions of Env. We suggest that the B cell specificity and compartment analysis described in this study are important complements to serological mapping studies for the examination of B cell responses against subspecificities of a variety of immunogens.
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Affiliation(s)
- Pia Dosenovic
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
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Zolla-Pazner S, Cohen S, Pinter A, Krachmarov C, Wrin T, Wang S, Lu S. Cross-clade neutralizing antibodies against HIV-1 induced in rabbits by focusing the immune response on a neutralizing epitope. Virology 2009; 392:82-93. [PMID: 19632700 DOI: 10.1016/j.virol.2009.05.039] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2009] [Revised: 05/18/2009] [Accepted: 05/28/2009] [Indexed: 11/17/2022]
Abstract
Studies were performed to induce cross-clade neutralizing antibodies (Abs) by testing various combinations of prime and boost constructs that focus the immune response on structurally-conserved epitopes in the V3 loop of HIV-1 gp120. Rabbits were immunized with gp120 DNA containing a V3 loop characterized by the GPGR motif at its tip, and/or with gp120 DNA with a V3 loop carrying the GPGQ motif. Priming was followed by boosts with V3-fusion proteins (V3-FPs) carrying the V3 sequence from a subtype B virus (GPGR motif), and/or with V3 sequences from subtypes A and C (GPGQ motif). The broadest and most consistent neutralizing responses were generated when using a clade C gp120 DNA prime and with the V3(B)-FP boost. Immune sera displayed neutralizing activity in three assays against pseudoviruses and primary isolates from subtypes A, AG, B, C, and D. Polyclonal Abs in the immune rabbit sera neutralized viruses that were not neutralized by pools of human anti-V3 monoclonal Abs. Greater than 80% of the neutralizing Abs were specific for V3, showing that the immune response could be focused on a neutralizing epitope and that vaccine-induced anti-V3 Abs have cross-clade neutralizing activity.
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Affiliation(s)
- Susan Zolla-Pazner
- New York University School of Medicine, 550 First Avenue, New York, NY, USA.
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