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Karasavvas N, Karnasuta C, Savadsuk H, Madnote S, Inthawong D, Chantakulkij S, Rittiroongrad S, Nitayaphan S, Pitisuttithum P, Thongcharoen P, Siriyanon V, Andrews CA, Barnett SW, Tartaglia J, Sinangil F, Francis DP, Robb ML, Michael NL, Ngauy V, de Souza MS, Paris RM, Excler JL, Kim JH, O'Connell RJ. IgG Antibody Responses to Recombinant gp120 Proteins, gp70V1/V2 Scaffolds, and a CyclicV2 Peptide in Thai Phase I/II Vaccine Trials Using Different Vaccine Regimens. AIDS Res Hum Retroviruses 2015; 31:1178-86. [PMID: 26234467 PMCID: PMC4651018 DOI: 10.1089/aid.2015.0034] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
RV144 correlates of risk analysis showed that IgG antibodies to gp70V1V2 scaffolds inversely correlated with risk of HIV acquisition. We investigated IgG antibody responses in RV135 and RV132, two ALVAC-HIV prime-boost vaccine trials conducted in Thailand prior to RV144. Both trials used ALVAC-HIV (vCP1521) at 0, 1, 3, and 6 months and HIV-1 gp120MNgD and gp120A244gD in alum (RV135) or gp120SF2 and gp120CM235 in MF59 (RV132) at 3 and 6 months. We assessed ELISA binding antibodies to the envelope proteins (Env) 92TH023, A244gD and MNgD, cyclicV2, and gp70V1V2 CaseA2 (subtype B) and 92TH023 (subtype CRF01_AE), and Env-specific IgG1 and IgG3. Antibody responses to gp120 A244gD, MNgD, and gp70V1V2 92TH023 scaffold were significantly higher in RV135 than in RV132. Antibodies to gp70V1V2 CaseA2 were detected only in RV135 vaccine recipients and IgG1 and IgG3 antibody responses to A244gD were significantly higher in RV135. IgG binding to gp70V1V2 CaseA2 and CRF01_AE scaffolds was higher with the AIDSVAX®B/E boost but both trials showed similar rates of antibody decline post-vaccination. MF59 did not result in higher IgG antibody responses compared to alum with the antigens tested. However, notable differences in the structure of the recombinant proteins and dosage used for immunizations may have contributed to the magnitude and specificity of IgG induced by the two trials.
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Affiliation(s)
- Nicos Karasavvas
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Chitraporn Karnasuta
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Hathairat Savadsuk
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Sirinan Madnote
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Dutsadee Inthawong
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Somsak Chantakulkij
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Surawach Rittiroongrad
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Sorachai Nitayaphan
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | | | | | - Vinai Siriyanon
- Research Institute for Health Sciences, Chiang Mai University, Chiang Mai, Thailand
| | | | - Susan W. Barnett
- Novartis Vaccines and Diagnostics, Inc., Cambridge, Massachusetts
| | | | - Faruk Sinangil
- Global Solutions for Infectious Diseases (GSID), South San Francisco, California
| | - Donald P. Francis
- Global Solutions for Infectious Diseases (GSID), South San Francisco, California
| | - Merlin L. Robb
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland
| | - Nelson L. Michael
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland
| | - Viseth Ngauy
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Mark S. de Souza
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - Robert M. Paris
- Military Malaria Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland
| | - Jean-Louis Excler
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland
| | - Jerome H. Kim
- International Vaccine Institute, Seoul, Republic of Korea
| | - Robert J. O'Connell
- Department of Retrovirology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
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102
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Nimmerjahn F. A constant threat for HIV: Fc-engineering to enhance broadly neutralizing antibody activity for immunotherapy of the acquired immunodeficiency syndrome. Eur J Immunol 2015; 45:2183-90. [PMID: 26140474 DOI: 10.1002/eji.201445386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Revised: 06/29/2015] [Accepted: 06/30/2015] [Indexed: 01/12/2023]
Abstract
Passive immunotherapy with polyclonal or hyperimmune serum immunoglobulin G (IgG) preparations provides an efficient means of protecting immunocompromised patients from microbial infections. More recently, the use of passive immunotherapy to prevent or to treat established infections with the human immunodeficiency virus (HIV) has gained much attention, due to promising preclinical data obtained in monkey and humanized mouse in vivo model systems, demonstrating that the transfer of HIV-specific antibodies can not only prevent HIV infection, but also diminish virus load during chronic infection. Furthermore, an array of broadly neutralizing HIV-specific antibodies has become available and the importance of the IgG constant region as a critical modulator of broadly neutralizing activity has been demonstrated. The aim of this review is to summarize the most recent findings with regard to the molecular and cellular mechanisms responsible for antibody-mediated clearance of HIV infection, and to discuss how this may help to improve HIV therapy via optimizing Fcγ-receptor-dependent activities of HIV-specific antibodies.
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Affiliation(s)
- Falk Nimmerjahn
- Institute of Genetics, Department of Biology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany
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103
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Adenoviral vectors elicit humoral immunity against variable loop 2 of clade C HIV-1 gp120 via "Antigen Capsid-Incorporation" strategy. Virology 2015; 487:75-84. [PMID: 26499044 DOI: 10.1016/j.virol.2015.10.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Revised: 10/07/2015] [Accepted: 10/08/2015] [Indexed: 11/23/2022]
Abstract
Adenoviral (Ad) vectors in combination with the "Antigen Capsid-Incorporation" strategy have been applied in developing HIV-1 vaccines, due to the vectors׳ abilities in incorporating and inducing immunity of capsid-incorporated antigens. Variable loop 2 (V2)-specific antibodies were suggested in the RV144 trial to correlate with reduced HIV-1 acquisition, which highlights the importance of developing novel HIV-1 vaccines by targeting the V2 loop. Therefore, the V2 loop of HIV-1 has been incorporated into the Ad capsid protein. We generated adenovirus serotype 5 (Ad5) vectors displaying variable loop 2 (V2) of HIV-1 gp120, with the "Antigen Capsid-Incorporation" strategy. To assess the incorporation capabilities on hexon hypervariable region1 (HVR1) and protein IX (pIX), 20aa or full length (43aa) of V2 and V1V2 (67aa) were incorporated, respectively. Immunizations with the recombinant vectors significantly generated antibodies against both linear and discontinuous V2 epitopes. The immunizations generated durable humoral immunity against V2. This study will lead to more stringent development of various serotypes of adenovirus-vectored V2 vaccine candidates, based on breakthroughs regarding the immunogenicity of V2.
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104
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Rationally Targeted Mutations at the V1V2 Domain of the HIV-1 Envelope to Augment Virus Neutralization by Anti-V1V2 Monoclonal Antibodies. PLoS One 2015; 10:e0141233. [PMID: 26491873 PMCID: PMC4619609 DOI: 10.1371/journal.pone.0141233] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 10/06/2015] [Indexed: 01/25/2023] Open
Abstract
HIV-1 envelope glycoproteins (Env) are the only viral antigens present on the virus surface and serve as the key targets for virus-neutralizing antibodies. However, HIV-1 deploys multiple strategies to shield the vulnerable sites on its Env from neutralizing antibodies. The V1V2 domain located at the apex of the HIV-1 Env spike is known to encompass highly variable loops, but V1V2 also contains immunogenic conserved elements recognized by cross-reactive antibodies. This study evaluates human monoclonal antibodies (mAbs) against V2 epitopes which overlap with the conserved integrin α4β7-binding LDV/I motif, designated as the V2i (integrin) epitopes. We postulate that the V2i Abs have weak or no neutralizing activities because the V2i epitopes are often occluded from antibody recognition. To gain insights into the mechanisms of the V2i occlusion, we evaluated three elements at the distal end of the V1V2 domain shown in the structure of V2i epitope complexed with mAb 830A to be important for antibody recognition of the V2i epitope. Amino-acid substitutions at position 179 that restore the LDV/I motif had minimal effects on virus sensitivity to neutralization by most V2i mAbs. However, a charge change at position 153 in the V1 region significantly increased sensitivity of subtype C virus ZM109 to most V2i mAbs. Separately, a disulfide bond introduced to stabilize the hypervariable region of V2 loop also enhanced virus neutralization by some V2i mAbs, but the effects varied depending on the virus. These data demonstrate that multiple elements within the V1V2 domain act independently and in a virus-dependent fashion to govern the antibody recognition and accessibility of V2i epitopes, suggesting the need for multi-pronged strategies to counter the escape and the shielding mechanisms obstructing the V2i Abs from neutralizing HIV-1.
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105
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Corey L, Gilbert PB, Tomaras GD, Haynes BF, Pantaleo G, Fauci AS. Immune correlates of vaccine protection against HIV-1 acquisition. Sci Transl Med 2015; 7:310rv7. [PMID: 26491081 PMCID: PMC4751141 DOI: 10.1126/scitranslmed.aac7732] [Citation(s) in RCA: 151] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The partial efficacy reported in the RV144 HIV vaccine trial in 2009 has driven the HIV vaccine field to define correlates of risk associated with HIV-1 acquisition and connect these functionally to preventing HIV infection. Immunological correlates, mainly including CD4(+) T cell responses to the HIV envelope and Fc-mediated antibody effector function, have been connected to reduced acquisition. These immunological correlates place immunological and genetic pressure on the virus. Indeed, antibodies directed at conserved regions of the V1V2 loop and antibodies that mediate antibody-dependent cellular cytotoxicity to HIV envelope in the absence of inhibiting serum immunoglobulin A antibodies correlated with decreased HIV risk. More recently, researchers have expanded their search with nonhuman primate studies using vaccine regimens that differ from that used in RV144; these studies indicate that non-neutralizing antibodies are associated with protection from experimental lentivirus challenge as well. These immunological correlates have provided the basis for the design of a next generation of vaccine regimens to improve upon the qualitative and quantitative degree of magnitude of these immune responses on HIV acquisition.
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Affiliation(s)
- Lawrence Corey
- HIV Vaccine Trials Network, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
| | - Peter B Gilbert
- Statistical Center for HIV/AIDS Research and Prevention, Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Georgia D Tomaras
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Barton F Haynes
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA
| | - Giuseppe Pantaleo
- Lausanne University Hospital and Swiss Vaccine Research Institute, Lausanne 1011, Switzerland
| | - Anthony S Fauci
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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106
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Tomaras GD, Haynes BF. Advancing Toward HIV-1 Vaccine Efficacy through the Intersections of Immune Correlates. Vaccines (Basel) 2015; 2:15-35. [PMID: 24932411 PMCID: PMC4053939 DOI: 10.3390/vaccines2010015] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Interrogating immune correlates of infection risk for efficacious and non-efficacious HIV-1 vaccine clinical trials have provided hypotheses regarding the mechanisms of induction of protective immunity to HIV-1. To date, there have been six HIV-1 vaccine efficacy trials (VAX003, Vaxgen, Inc., San Francisco, CA, USA), VAX004 (Vaxgen, Inc.), HIV-1 Vaccine Trials Network (HVTN) 502 (Step), HVTN 503 (Phambili), RV144 (sponsored by the U.S. Military HIV Research Program, MHRP) and HVTN 505). Cellular, humoral, host genetic and virus sieve analyses of these human clinical trials each can provide information that may point to potentially protective mechanisms for vaccine-induced immunity. Critical to staying on the path toward development of an efficacious vaccine is utilizing information from previous human and non-human primate studies in concert with new discoveries of basic HIV-1 host-virus interactions. One way that past discoveries from correlate analyses can lead to novel inventions or new pathways toward vaccine efficacy is to examine the intersections where different components of the correlate analyses overlap (e.g., virus sieve analysis combined with humoral correlates) that can point to mechanistic hypotheses. Additionally, differences in durability among vaccine-induced T- and B-cell responses indicate that time post-vaccination is an important variable. Thus, understanding the nature of protective responses, the degree to which such responses have, or have not, as yet, been induced by previous vaccine trials and the design of strategies to induce durable T- and B-cell responses are critical to the development of a protective HIV-1 vaccine.
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Affiliation(s)
- Georgia D. Tomaras
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-919-681-5598; Fax: +1-919-684-5230
| | - Barton F. Haynes
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-919-681-5598; Fax: +1-919-684-5230
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107
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Dosenovic P, von Boehmer L, Escolano A, Jardine J, Freund NT, Gitlin AD, McGuire AT, Kulp DW, Oliveira T, Scharf L, Pietzsch J, Gray MD, Cupo A, van Gils MJ, Yao KH, Liu C, Gazumyan A, Seaman MS, Björkman PJ, Sanders RW, Moore JP, Stamatatos L, Schief WR, Nussenzweig MC. Immunization for HIV-1 Broadly Neutralizing Antibodies in Human Ig Knockin Mice. Cell 2015; 161:1505-15. [PMID: 26091035 DOI: 10.1016/j.cell.2015.06.003] [Citation(s) in RCA: 205] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 05/29/2015] [Accepted: 05/29/2015] [Indexed: 12/11/2022]
Abstract
A subset of individuals infected with HIV-1 develops broadly neutralizing antibodies (bNAbs) that can prevent infection, but it has not yet been possible to elicit these antibodies by immunization. To systematically explore how immunization might be tailored to produce them, we generated mice expressing the predicted germline or mature heavy chains of a potent bNAb to the CD4 binding site (CD4bs) on the HIV-1 envelope glycoprotein (Env). Immunogens specifically designed to activate B cells bearing germline antibodies are required to initiate immune responses, but they do not elicit bNAbs. In contrast, native-like Env trimers fail to activate B cells expressing germline antibodies but elicit bNAbs by selecting for a restricted group of light chains bearing specific somatic mutations that enhance neutralizing activity. The data suggest that vaccination to elicit anti-HIV-1 antibodies will require immunization with a succession of related immunogens.
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Affiliation(s)
- Pia Dosenovic
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Lotta von Boehmer
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Amelia Escolano
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Joseph Jardine
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Natalia T Freund
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Alexander D Gitlin
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Andrew T McGuire
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Daniel W Kulp
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Thiago Oliveira
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Louise Scharf
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - John Pietzsch
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Matthew D Gray
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Albert Cupo
- Department of Microbiology and Immunology, Weill Medical College, Cornell University, New York, NY 10065, USA
| | - Marit J van Gils
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Kai-Hui Yao
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Cassie Liu
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Anna Gazumyan
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA; Howard Hughes Medical Institute
| | - Michael S Seaman
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Pamela J Björkman
- Howard Hughes Medical Institute; Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Rogier W Sanders
- Department of Microbiology and Immunology, Weill Medical College, Cornell University, New York, NY 10065, USA; Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - John P Moore
- Department of Microbiology and Immunology, Weill Medical College, Cornell University, New York, NY 10065, USA
| | - Leonidas Stamatatos
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA; Department of Global Health, University of Washington, Seattle, WA 98109, USA
| | - William R Schief
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA 92037, USA; IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA; Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, CA 92037, USA; Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02129, USA.
| | - Michel C Nussenzweig
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA; Howard Hughes Medical Institute.
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108
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Girard MP, Picot V, Longuet C, Nabel GJ. Report of the 2014 Cent Gardes HIV Vaccine Conference-Part 2: Cell-mediated immunity, mucosal protection, and clinical trials: Fondation Mérieux Conference Center, Veyrier du Lac, France, 5-7 October, 2014. Vaccine 2015; 33:4051-5. [PMID: 26143614 DOI: 10.1016/j.vaccine.2015.06.074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 06/04/2015] [Accepted: 06/20/2015] [Indexed: 11/17/2022]
Abstract
The 2014 Cent Gardes Conference took place on October 5-7, 2014, at the Fondation Mérieux Conference Center, on the shores of the Annecy Lake and aimed to review the progress and promise of HIV vaccines. The elicitation of broadly neutralizing antibodies (bNAbs), their use in passive immunization, as well as their genetic delivery (vector immunoprophylaxis) by a recombinant Adenovirus-associated virus (AAV) vector were reviewed in a preceding article [1]. Approaches to the elicitation of long-lasting T cell or mucosal immunity were also discussed and are now reviewed here. The possibility of eliciting mucosal IgAs was discussed, since it was demonstrated that transcytosis-blocking IgAs can protect monkeys against repeated vaginal challenge with a pathogenic chimeric simian and human immunodeficiency virus (SHIV). The possibility of purging the HIV reservoirs from HIV-infected persons and developing a cure of the disease was also discussed.
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Affiliation(s)
- Marc P Girard
- French National Academy of Medicine, 16 rue Bonaparte, 75006 Paris, France.
| | | | | | - Gary J Nabel
- Sanofi, 640 Memorial Drive, Cambridge, MA 021139, United States.
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109
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Association of HIV-1 Envelope-Specific Breast Milk IgA Responses with Reduced Risk of Postnatal Mother-to-Child Transmission of HIV-1. J Virol 2015. [PMID: 26202232 DOI: 10.1128/jvi.01560-15] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
UNLABELLED Infants born to HIV-1-infected mothers in resource-limited areas where replacement feeding is unsafe and impractical are repeatedly exposed to HIV-1 throughout breastfeeding. Despite this, the majority of infants do not contract HIV-1 postnatally, even in the absence of maternal antiretroviral therapy. This suggests that immune factors in breast milk of HIV-1-infected mothers help to limit vertical transmission. We compared the HIV-1 envelope-specific breast milk and plasma antibody responses of clade C HIV-1-infected postnatally transmitting and nontransmitting mothers in the control arm of the Malawi-based Breastfeeding Antiretrovirals and Nutrition Study using multivariable logistic regression modeling. We found no association between milk or plasma neutralization activity, antibody-dependent cell-mediated cytotoxicity, or HIV-1 envelope-specific IgG responses and postnatal transmission risk. While the envelope-specific breast milk and plasma IgA responses also did not reach significance in predicting postnatal transmission risk in the primary model after correction for multiple comparisons, subsequent exploratory analysis using two distinct assay methodologies demonstrated that the magnitudes of breast milk total and secretory IgA responses against a consensus HIV-1 envelope gp140 (B.con env03) were associated with reduced postnatal transmission risk. These results suggest a protective role for mucosal HIV-1 envelope-specific IgA responses in the context of postnatal virus transmission. This finding supports further investigations into the mechanisms by which mucosal IgA reduces risk of HIV-1 transmission via breast milk and into immune interventions aimed at enhancing this response. IMPORTANCE Infants born to HIV-1-infected mothers are repeatedly exposed to the virus in breast milk. Remarkably, the transmission rate is low, suggesting that immune factors in the breast milk of HIV-1-infected mothers help to limit transmission. We compared the antibody responses in plasma and breast milk of HIV-1-transmitting and -nontransmitting mothers to identify responses that correlated with reduced risk of postnatal HIV-1 transmission. We found that neither plasma nor breast milk IgG antibody responses were associated with risk of HIV-1 transmission. In contrast, the magnitudes of the breast milk IgA and secretory IgA responses against HIV-1 envelope proteins were associated with reduced risk of postnatal HIV-1 transmission. The results of this study support further investigations of the mechanisms by which mucosal IgA may reduce the risk of HIV-1 transmission via breastfeeding and the development of strategies to enhance milk envelope-specific IgA responses to reduce mother-to-child HIV transmission and promote an HIV-free generation.
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110
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Excler JL, Robb ML, Kim JH. Prospects for a globally effective HIV-1 vaccine. Vaccine 2015; 33 Suppl 4:D4-12. [PMID: 26100921 DOI: 10.1016/j.vaccine.2015.03.059] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2015] [Revised: 03/07/2015] [Accepted: 03/10/2015] [Indexed: 11/28/2022]
Abstract
A globally effective vaccine strategy must cope with the broad genetic diversity of HIV and contend with multiple transmission modalities. Understanding correlates of protection and the role of diversity in limiting protective vaccines with those correlates is key. RV144 was the first HIV-1 vaccine trial to demonstrate efficacy against HIV-1 infection. A correlates analysis compared vaccine-induced immune responses in vaccinated-infected and vaccinated-uninfected volunteers suggested that IgG specific for the V1V2 region of gp120 was associated with reduced risk of HIV-1 infection and that plasma Env IgA was directly correlated with infection risk. RV144 and recent NHP challenge studies suggest that Env is essential and perhaps sufficient to induce protective antibody responses against mucosally acquired HIV-1. Whether RV144 immune correlates can apply to different HIV vaccines, to populations with different modes and intensity of transmission, or to divergent HIV-1 subtypes remains unknown. Newer prime-boost mosaic and conserved sequence immunization strategies aiming at inducing immune responses of greater breadth and depth as well as the development of immunogens inducing broadly neutralizing antibodies should be actively pursued. Efficacy trials are now planned in heterosexual populations in southern Africa and MSM in Thailand. Although NHP challenge studies may guide vaccine development, human efficacy trials remain key to answer the critical questions leading to the development of a global HIV-1 vaccine for licensure.
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Affiliation(s)
- Jean-Louis Excler
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Bethesda, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA.
| | - Merlin L Robb
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Bethesda, MD, USA; Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Jerome H Kim
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Bethesda, MD, USA
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111
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Nicely NI, Wiehe K, Kepler TB, Jaeger FH, Dennison SM, Rerks-Ngarm S, Nitayaphan S, Pitisuttithum P, Kaewkungwal J, Robb ML, O'Connell RJ, Michael NL, Kim JH, Liao HX, Munir Alam S, Hwang KK, Bonsignori M, Haynes BF. Structural analysis of the unmutated ancestor of the HIV-1 envelope V2 region antibody CH58 isolated from an RV144 vaccine efficacy trial vaccinee. EBioMedicine 2015; 2:713-22. [PMID: 26288844 PMCID: PMC4534707 DOI: 10.1016/j.ebiom.2015.06.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 06/17/2015] [Accepted: 06/18/2015] [Indexed: 11/25/2022] Open
Abstract
Human monoclonal antibody CH58 isolated from an RV144 vaccinee binds at Lys169 of the HIV-1 Env gp120 V2 region, a site of vaccine-induced immune pressure. CH58 neutralizes HIV-1 CRF_01 AE strain 92TH023 and mediates ADCC against CD4 + T cell targets infected with CRF_01 AE tier 2 virus. CH58 and other antibodies that bind to a gp120 V2 epitope have a second light chain complementarity determining region (LCDR2) bearing a glutamic acid, aspartic acid (ED) motif involved in forming salt bridges with polar, basic side amino acid side chains in V2. In an effort to learn how V2 responses develop, we determined the crystal structures of the CH58-UA antibody unliganded and bound to V2 peptide. The structures showed an LCDR2 structurally pre-conformed from germline to interact with V2 residue Lys169. LCDR3 was subject to conformational selection through the affinity maturation process. Kinetic analyses demonstrate that only a few contacts were responsible for a 2000-fold increase in KD through maturation, and this effect was predominantly due to an improvement in off-rate. This study shows that preconformation and preconfiguration can work in concert to produce antibodies with desired immunogenic properties. With only 2-3% mutation from germline, the HIV-1 antibody CH58 developed neutralizing and ADCC capabilities. The LCDR2 Glu–Asp motif of the RV144 antibody CH58 is pre-conformed from germline to interact with the gp120 V2 loop. Affinity and neutralization gains resulted from tuning local interactions rather than gross sequence or structure changes. Structural analyses show the second light chain complementarity determining region Glu–Asp motif of the CH58 antibody isolated from an RV144 vaccinee is optimally pre-conformed from germline to interact with the gp120 V2 loop. The increased binding affinity and neutralization capacity of the mature antibody compared to its germline precursor were achieved with only 2–3% mutation from germline, and the fact that these gains appeared to be a result of the tuning of local interactions rather than gross sequential or conformational changes provides hope that a rational immunogen design for HIV-1 treatment may become a reality.
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Affiliation(s)
- Nathan I Nicely
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - Kevin Wiehe
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - Thomas B Kepler
- Boston University Department of Microbiology, Boston, MA, USA
| | - Frederick H Jaeger
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - S Moses Dennison
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | | | | | | | | | - Merlin L Robb
- Henry Jackson Foundation HIV Program, US Military HIV Research Program, Bethesda, MD, USA
| | | | - Nelson L Michael
- US Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Jerome H Kim
- US Military HIV Research Program (MHRP), Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Hua-Xin Liao
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - S Munir Alam
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - Kwan-Ki Hwang
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - Mattia Bonsignori
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
| | - Barton F Haynes
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC, USA
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112
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Menon V, Priya RS, Labranche C, Montefiori D, Mahalingam S, Kalyanaraman VS, Pal R. Characterization of protective immune response elicited by a trimeric envelope protein from an Indian clade C HIV-1 isolate in rhesus macaques. J Med Primatol 2015; 44:275-85. [PMID: 26075700 DOI: 10.1111/jmp.12178] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/11/2015] [Indexed: 11/30/2022]
Abstract
BACKGROUND Recent preclinical studies have demonstrated the use of properly folded trimeric HIV-1 envelope proteins as immunogen for eliciting protecting immune response in macaques. METHODS Trimeric gp145 protein of Indian clade C HIV-1 (93IN101) was characterized for antigenicity by evaluating its binding to sCD4, and several monoclonal antibodies to HIV-1 by bio-layer interferometry. Ten macaques were immunized four times with purified gp145 in adjuplex adjuvant, and serum antibodies were characterized for binding to gp145 and neutralization. Immunized macaques were subjected to weekly low-dose vaginal challenge with SHIV1157-ipEL-p for 8 weeks. RESULTS Env protein elicited strong antibody response in macaques. Following challenge, seven of ten immunized macaques resisted challenge, while six of eight control animals were infected. CONCLUSIONS Env proteins from a clade C Indian isolate can elicit protective immune response and therefore may be a candidate for inclusion in a multiclade-based HIV-1 vaccine.
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Affiliation(s)
- Veena Menon
- Advanced BioScience Laboratories, Rockville, MD, USA
| | | | | | | | | | | | - Ranajit Pal
- Advanced BioScience Laboratories, Rockville, MD, USA
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113
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Ambati A, Valentini D, Montomoli E, Lapini G, Biuso F, Wenschuh H, Magalhaes I, Maeurer M. H1N1 viral proteome peptide microarray predicts individuals at risk for H1N1 infection and segregates infection versus Pandemrix(®) vaccination. Immunology 2015; 145:357-66. [PMID: 25639813 PMCID: PMC4479535 DOI: 10.1111/imm.12448] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 01/02/2015] [Accepted: 01/26/2015] [Indexed: 12/30/2022] Open
Abstract
A high content peptide microarray containing the entire influenza A virus [A/California/08/2009(H1N1)] proteome and haemagglutinin proteins from 12 other influenza A subtypes, including the haemagglutinin from the [A/South Carolina/1/1918(H1N1)] strain, was used to gauge serum IgG epitope signatures before and after Pandemrix® vaccination or H1N1 infection in a Swedish cohort during the pandemic influenza season 2009. A very narrow pattern of pandemic flu-specific IgG epitope recognition was observed in the serum from individuals who later contracted H1N1 infection. Moreover, the pandemic influenza infection generated IgG reactivity to two adjacent epitopes of the neuraminidase protein. The differential serum IgG recognition was focused on haemagglutinin 1 (H1) and restricted to classical antigenic sites (Cb) in both the vaccinated controls and individuals with flu infections. We further identified a novel epitope VEPGDKITFEATGNL on the Ca antigenic site (251–265) of the pandemic flu haemagglutinin, which was exclusively recognized in serum from individuals with previous vaccinations and never in serum from individuals with H1N1 infection (confirmed by RNA PCR analysis from nasal swabs). This epitope was mapped to the receptor-binding domain of the influenza haemagglutinin and could serve as a correlate of immune protection in the context of pandemic flu. The study shows that unbiased epitope mapping using peptide microarray technology leads to the identification of biologically and clinically relevant target structures. Most significantly an H1N1 infection induced a different footprint of IgG epitope recognition patterns compared with the pandemic H1N1 vaccine.
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Affiliation(s)
- Aditya Ambati
- Therapeutic Immunology Unit, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.,Centre for Allogeneic Stem Cell Transplantation (CAST), Karolinska University Hospital, Stockholm, Sweden
| | - Davide Valentini
- Therapeutic Immunology Unit, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.,Centre for Allogeneic Stem Cell Transplantation (CAST), Karolinska University Hospital, Stockholm, Sweden
| | - Emanuele Montomoli
- Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Guilia Lapini
- VisMederi srl, Enterprise in Life Science, Siena, Italy
| | | | | | - Isabelle Magalhaes
- Therapeutic Immunology Unit, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.,Centre for Allogeneic Stem Cell Transplantation (CAST), Karolinska University Hospital, Stockholm, Sweden
| | - Markus Maeurer
- Therapeutic Immunology Unit, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden.,Centre for Allogeneic Stem Cell Transplantation (CAST), Karolinska University Hospital, Stockholm, Sweden
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114
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Brown J, Excler JL, Kim JH. New prospects for a preventive HIV-1 vaccine. J Virus Erad 2015; 1:78-88. [PMID: 26523292 PMCID: PMC4625840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The immune correlates of risk analysis and recent non-human primate (NHP) challenge studies have generated hypotheses that suggest HIV-1 envelope may be essential and, perhaps, sufficient to induce protective antibody responses against HIV-1 acquisition at the mucosal entry. New prime-boost mosaic and conserved-sequence, together with replicating vector immunisation strategies aiming at inducing immune responses or greater breadth, as well as the development of immunogens inducing broadly neutralising antibodies and mucosal responses, should be actively pursued and tested in humans. Whether the immune correlates of risk identified in RV144 can be extended to other vaccines, other populations, or different modes and intensity of transmission, and against increasing HIV-1 genetic diversity, remains to be demonstrated. Although NHP challenge studies may guide vaccine development, human efficacy trials remain key for answering the critical questions leading to the development of a global HIV-1 vaccine for licensure.
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Affiliation(s)
| | - Jean-Louis Excler
- US Military HIV Research Program,
Bethesda,
MD,
USA,The Henry M Jackson Foundation for the Advancement of Military Medicine,
Bethesda,
MD,
USA,Corresponding author: Jean-Louis Excler,
US Military HIV Research Program,
6720-A Rockledge Drive, Suite 400Bethesda,
MD20817,
USA
| | - Jerome H Kim
- US Military HIV Research Program,
Walter Reed Army Institute of Research,
Silver Spring,
MD,
USA
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115
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Ratto-Kim S, de Souza MS, Currier JR, Karasavvas N, Sidney J, Rolland M, Valencia-Micolta A, Madnote S, Sette A, Nitayaphan S, Pitisuttuthum P, Kaewkungwal J, Rerks-Ngarm S, O’Connell R, Michael N, Robb ML, Marovich M, Kim JH. Identification of immunodominant CD4-restricted epitopes co-located with antibody binding sites in individuals vaccinated with ALVAC-HIV and AIDSVAX B/E. PLoS One 2015; 10:e0115582. [PMID: 25665096 PMCID: PMC4321833 DOI: 10.1371/journal.pone.0115582] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Accepted: 11/29/2014] [Indexed: 11/18/2022] Open
Abstract
We performed fine epitope mapping of the CD4+ responses in the ALVAC-HIV-AIDSVAX B/E prime-boost regimen in the Thai Phase III trial (RV144). Non-transformed Env-specific T cell lines established from RV144 vaccinees were used to determine the fine epitope mapping of the V2 and C1 responses and the HLA class II restriction. Data showed that there are two CD4+ epitopes contained within the V2 loop: one encompassing the α4β7 integrin binding site (AA179-181) and the other nested between two previously described genetic sieve signatures (AA169, AA181). There was no correlation between the frequencies of CD4+ fine epitope responses and binding antibody.
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Affiliation(s)
- Silvia Ratto-Kim
- United States Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, United States of America
- * E-mail:
| | - Mark S. de Souza
- United States Military HIV Research Program/United States Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, 10400, Thailand
| | - Jeffrey R. Currier
- United States Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, United States of America
| | - Nicos Karasavvas
- United States Military HIV Research Program/United States Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, 10400, Thailand
| | - John Sidney
- La Jolla Institute for Allergy and Immunology, La Jolla, CA, 92037, United States of America
| | - Morgane Rolland
- United States Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, United States of America
| | - Anais Valencia-Micolta
- United States Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, United States of America
| | - Sirinan Madnote
- United States Military HIV Research Program/United States Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, 10400, Thailand
| | - Alessandro Sette
- La Jolla Institute for Allergy and Immunology, La Jolla, CA, 92037, United States of America
| | - Sorachai Nitayaphan
- Thai Component, Armed Forces Research Institute of Medical Sciences, Bangkok, 10400, Thailand
| | - Punnee Pitisuttuthum
- Vaccine Trials Centre, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Jaranit Kaewkungwal
- Centre of Excellence for Biomedical and Public Health Informatics, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Supachai Rerks-Ngarm
- Department of Disease Control, Ministry of Public Health, Nonthaburi, 11000, Thailand
| | - Robert O’Connell
- United States Military HIV Research Program/United States Army Medical Component, Armed Forces Research Institute of Medical Sciences, Bangkok, 10400, Thailand
| | - Nelson Michael
- United States Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, United States of America
| | - Merlin L. Robb
- United States Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, United States of America
| | - Mary Marovich
- Office of AIDS Research, National Institutes of Health, Bethesda, MD, 20892, United States of America
| | - Jerome H. Kim
- United States Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, 20910, United States of America
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Stephenson KE, Neubauer GH, Reimer U, Pawlowski N, Knaute T, Zerweck J, Korber BT, Barouch DH. Quantification of the epitope diversity of HIV-1-specific binding antibodies by peptide microarrays for global HIV-1 vaccine development. J Immunol Methods 2015; 416:105-23. [PMID: 25445329 PMCID: PMC4324361 DOI: 10.1016/j.jim.2014.11.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 11/10/2014] [Accepted: 11/10/2014] [Indexed: 01/08/2023]
Abstract
An effective vaccine against human immunodeficiency virus type 1 (HIV-1) will have to provide protection against a vast array of different HIV-1 strains. Current methods to measure HIV-1-specific binding antibodies following immunization typically focus on determining the magnitude of antibody responses, but the epitope diversity of antibody responses has remained largely unexplored. Here we describe the development of a global HIV-1 peptide microarray that contains 6564 peptides from across the HIV-1 proteome and covers the majority of HIV-1 sequences in the Los Alamos National Laboratory global HIV-1 sequence database. Using this microarray, we quantified the magnitude, breadth, and depth of IgG binding to linear HIV-1 sequences in HIV-1-infected humans and HIV-1-vaccinated humans, rhesus monkeys and guinea pigs. The microarray measured potentially important differences in antibody epitope diversity, particularly regarding the depth of epitope variants recognized at each binding site. Our data suggest that the global HIV-1 peptide microarray may be a useful tool for both preclinical and clinical HIV-1 research.
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Affiliation(s)
- Kathryn E Stephenson
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - George H Neubauer
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Ulf Reimer
- JPT Peptide Technologies, Berlin, Germany
| | | | | | | | - Bette T Korber
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM, United States
| | - Dan H Barouch
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States; Ragon Institute of MGH, MIT, and Harvard, Boston, MA, United States.
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117
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Yates NL, Liao HX, Fong Y, deCamp A, Vandergrift NA, Williams WT, Alam SM, Ferrari G, Yang ZY, Seaton KE, Berman PW, Alpert MD, Evans DT, O'Connell RJ, Francis D, Sinangil F, Lee C, Nitayaphan S, Rerks-Ngarm S, Kaewkungwal J, Pitisuttithum P, Tartaglia J, Pinter A, Zolla-Pazner S, Gilbert PB, Nabel GJ, Michael NL, Kim JH, Montefiori DC, Haynes BF, Tomaras GD. Vaccine-induced Env V1-V2 IgG3 correlates with lower HIV-1 infection risk and declines soon after vaccination. Sci Transl Med 2014; 6:228ra39. [PMID: 24648342 DOI: 10.1126/scitranslmed.3007730] [Citation(s) in RCA: 368] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
HIV-1-specific immunoglobulin G (IgG) subclass antibodies bind to distinct cellular Fc receptors. Antibodies of the same epitope specificity but of a different subclass therefore can have different antibody effector functions. The study of IgG subclass profiles between different vaccine regimens used in clinical trials with divergent efficacy outcomes can provide information on the quality of the vaccine-induced B cell response. We show that HIV-1-specific IgG3 distinguished two HIV-1 vaccine efficacy studies (RV144 and VAX003 clinical trials) and correlated with decreased risk of HIV-1 infection in a blinded follow-up case-control study with the RV144 vaccine. HIV-1-specific IgG3 responses were not long-lived, which was consistent with the waning efficacy of the RV144 vaccine. These data suggest that specific vaccine-induced HIV-1 IgG3 should be tested in future studies of immune correlates in HIV-1 vaccine efficacy trials.
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118
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Chung AW, Ghebremichael M, Robinson H, Brown E, Choi I, Lane S, Dugast AS, Schoen MK, Rolland M, Suscovich TJ, Mahan AE, Liao L, Streeck H, Andrews C, Rerks-Ngarm S, Nitayaphan S, de Souza MS, Kaewkungwal J, Pitisuttithum P, Francis D, Michael NL, Kim JH, Bailey-Kellogg C, Ackerman ME, Alter G. Polyfunctional Fc-effector profiles mediated by IgG subclass selection distinguish RV144 and VAX003 vaccines. Sci Transl Med 2014; 6:228ra38. [PMID: 24648341 DOI: 10.1126/scitranslmed.3007736] [Citation(s) in RCA: 320] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The human phase 2B RV144 ALVAC-HIV vCP1521/AIDSVAX B/E vaccine trial, held in Thailand, resulted in an estimated 31.2% efficacy against HIV infection. By contrast, vaccination with VAX003 (consisting of only AIDSVAX B/E) was not protective. Because protection within RV144 was observed in the absence of neutralizing antibody activity or cytotoxic T cell responses, we speculated that the specificity or qualitative differences in Fc-effector profiles of nonneutralizing antibodies may have accounted for the efficacy differences observed between the two trials. We show that the RV144 regimen elicited nonneutralizing antibodies with highly coordinated Fc-mediated effector responses through the selective induction of highly functional immunoglobulin G3 (IgG3). By contrast, VAX003 elicited monofunctional antibody responses influenced by IgG4 selection, which was promoted by repeated AIDSVAX B/E protein boosts. Moreover, only RV144 induced IgG1 and IgG3 antibodies targeting the crown of the HIV envelope V2 loop, albeit with limited coverage of breakthrough viral sequences. These data suggest that subclass selection differences associated with coordinated humoral functional responses targeting strain-specific protective V2 loop epitopes may underlie differences in vaccine efficacy observed between these two vaccine trials.
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Affiliation(s)
- Amy W Chung
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, and Harvard, Boston, MA 02139, USA
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119
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Zolla-Pazner S, Edlefsen PT, Rolland M, Kong XP, deCamp A, Gottardo R, Williams C, Tovanabutra S, Sharpe-Cohen S, Mullins JI, deSouza MS, Karasavvas N, Nitayaphan S, Rerks-Ngarm S, Pitisuttihum P, Kaewkungwal J, O'Connell RJ, Robb ML, Michael NL, Kim JH, Gilbert P. Vaccine-induced Human Antibodies Specific for the Third Variable Region of HIV-1 gp120 Impose Immune Pressure on Infecting Viruses. EBioMedicine 2014; 1:37-45. [PMID: 25599085 PMCID: PMC4293639 DOI: 10.1016/j.ebiom.2014.10.022] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
To evaluate the role of V3-specific IgG antibodies (Abs) in the RV144 clinical HIV vaccine trial, which reduced HIV-1 infection by 31.2%, the anti-V3 Ab response was assessed. Vaccinees' V3 Abs were highly cross-reactive with cyclic V3 peptides (cV3s) from diverse virus subtypes. Sieve analysis of CRF01_AE breakthrough viruses from 43 vaccine- and 66 placebo-recipients demonstrated an estimated vaccine efficacy of 85% against viruses with amino acids mismatching the vaccine at V3 site 317 (p = 0.004) and 52% against viruses matching the vaccine at V3 site 307 (p = 0.004). This analysis was supported by data showing that vaccinees' plasma Abs were less reactive with I307 when replaced with residues found more often in vaccinees' breakthrough viruses. Simultaneously, viruses with mutations at F317 were less infectious, possibly due to the contribution of F317 to optimal formation of the V3 hydrophobic core. These data suggest that RV144-induced V3-specific Abs imposed immune pressure on infecting viruses and inform efforts to design an HIV vaccine. The RV144 vaccine reduced infection by viruses with isoleucine in V3 position 307. Many vaccine-induced antibodies are cross-reactive and target an epitope including I307. There was selection for breakthrough viruses carrying F317 in V3 (p = 0.004). F317 is needed to maintain optimal infectivity. F317 is a poor or non-contact residue for vaccine induced V3 antibodies.
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Affiliation(s)
- Susan Zolla-Pazner
- New York Veterans Affairs Harbor Healthcare System, 423 East 23 Street, New York, NY 10010, USA ; New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Paul T Edlefsen
- Vaccine and Infectious Disease Division, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., M2-C200, Seattle, WA 98109, USA
| | - Morgane Rolland
- Department of Retrovirology, Walter Reed Army Institute of Research, Building 503, Silver Spring, MD 20910, USA
| | - Xiang-Peng Kong
- New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Allan deCamp
- Vaccine and Infectious Disease Division, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., M2-C200, Seattle, WA 98109, USA
| | - Raphael Gottardo
- Vaccine and Infectious Disease Division, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., M2-C200, Seattle, WA 98109, USA
| | - Constance Williams
- New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - Sodsai Tovanabutra
- Department of Retrovirology, Walter Reed Army Institute of Research, Building 503, Silver Spring, MD 20910, USA
| | - Sandra Sharpe-Cohen
- New York University School of Medicine, 550 First Avenue, New York, NY 10016, USA
| | - James I Mullins
- Department of Microbiology, University of Washington, 358B Rosen Building, Campus box 358070, Seattle, WA 98195
| | - Mark S deSouza
- Thai Red Cross AIDS Research Center 104, Tower 2, Rajdumari Rd. Pathumwan, Bangkok, Thailand, 10330
| | - Nicos Karasavvas
- Armed Forces Research Institute of Medical Science (AFRIMS) Department of Retrovirology Humoral Immunology and Assessment Laboratory, 315/6 Rajvithi Rd. Bangkok, 10400, Thailand
| | - Sorachai Nitayaphan
- Armed Forces Research Institute of Medical Science (AFRIMS) Department of Retrovirology Humoral Immunology and Assessment Laboratory, 315/6 Rajvithi Rd. Bangkok, 10400, Thailand
| | - Supachai Rerks-Ngarm
- Department of Disease Control, Ministry of Public Health, Nonthaburi, 11000, Thailand
| | - Punnee Pitisuttihum
- Department of Clinical Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand
| | - Jaranit Kaewkungwal
- Department of Clinical Tropical Medicine, Mahidol University, 420/6 Ratchawithi Road, Ratchathewi, Bangkok 10400, Thailand
| | - Robert J O'Connell
- Armed Forces Research Institute of Medical Science (AFRIMS) Department of Retrovirology Humoral Immunology and Assessment Laboratory, 315/6 Rajvithi Rd. Bangkok, 10400, Thailand
| | - Merlin L Robb
- U.S. Army Military HIV Research Program, 6720A Rockledge Dr., Suite 400, Bethesda MD, 20817
| | - Nelson L Michael
- U.S. Army Military HIV Research Program, 6720A Rockledge Dr., Suite 400, Bethesda MD, 20817
| | - Jerome H Kim
- U.S. Army Military HIV Research Program, 6720A Rockledge Dr., Suite 400, Bethesda MD, 20817
| | - Peter Gilbert
- Vaccine and Infectious Disease Division, Public Health Sciences Division, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., M2-C200, Seattle, WA 98109, USA
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120
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CD8 and CD4 epitope predictions in RV144: no strong evidence of a T-cell driven sieve effect in HIV-1 breakthrough sequences from trial participants. PLoS One 2014; 9:e111334. [PMID: 25350851 PMCID: PMC4211711 DOI: 10.1371/journal.pone.0111334] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 09/23/2014] [Indexed: 11/19/2022] Open
Abstract
The modest protection afforded by the RV144 vaccine offers an opportunity to evaluate its mechanisms of protection. Differences between HIV-1 breakthrough viruses from vaccine and placebo recipients can be attributed to the RV144 vaccine as this was a randomized and double-blinded trial. CD8 and CD4 T cell epitope repertoires were predicted in HIV-1 proteomes from 110 RV144 participants. Predicted Gag epitope repertoires were smaller in vaccine than in placebo recipients (p = 0.019). After comparing participant-derived epitopes to corresponding epitopes in the RV144 vaccine, the proportion of epitopes that could be matched differed depending on the protein conservation (only 36% of epitopes in Env vs 84–91% in Gag/Pol/Nef for CD8 predicted epitopes) or on vaccine insert subtype (55% against CRF01_AE vs 7% against subtype B). To compare predicted epitopes to the vaccine, we analyzed predicted binding affinity and evolutionary distance measurements. Comparisons between the vaccine and placebo arm did not reveal robust evidence for a T cell driven sieve effect, although some differences were noted in Env-V2 (0.022≤p-value≤0.231). The paucity of CD8 T cell responses identified following RV144 vaccination, with no evidence for V2 specificity, considered together both with the association of decreased infection risk in RV 144 participants with V-specific antibody responses and a V2 sieve effect, lead us to hypothesize that this sieve effect was not T cell specific. Overall, our results did not reveal a strong differential impact of vaccine-induced T cell responses among breakthrough infections in RV144 participants.
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121
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Kim JH, Excler JL, Michael NL. Lessons from the RV144 Thai phase III HIV-1 vaccine trial and the search for correlates of protection. Annu Rev Med 2014; 66:423-37. [PMID: 25341006 DOI: 10.1146/annurev-med-052912-123749] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
RV144 remains the only HIV-1 vaccine trial to demonstrate efficacy against HIV-1 acquisition. The prespecified analysis of immune correlates of risk showed that antibodies directed against the V1V2 region of gp120, in particular the IgG1 and IgG3 subclass mediating antibody-dependent cell-mediated cytotoxicity, seem to play a predominant role in protection against HIV-1 acquisition and that plasma envelope (Env)-specific IgA antibodies were directly correlated with risk. RV144 and recent nonhuman primate challenge studies suggest that Env is essential, and perhaps sufficient, to induce protective antibody responses against mucosal HIV-1 acquisition. Follow-up clinical trials are ongoing to further dissect the immune responses elicited by the RV144 ALVAC-HIV and AIDSVAX® B/E regimen. The study of gp120 Env immunogens and immune correlates of risk has resulted in the development of improved antigens. Whether the RV144 immune correlates of risk will generalize to other populations vaccinated with similar immunogens with different modes and intensity of transmission remains to be demonstrated. Efficacy trials are now planned in heterosexual populations in southern Africa and men who have sex with men in Thailand.
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Affiliation(s)
- Jerome H Kim
- US Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland 20910; ,
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122
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Stieh DJ, King DF, Klein K, Liu P, Shen X, Hwang KK, Ferrari G, Montefiori DC, Haynes B, Pitisuttithum P, Kaewkungwal J, Nitayaphan S, Rerks-Ngarm S, Michael NL, Robb ML, Kim JH, Denny TN, Tomaras GD, Shattock RJ. Aggregate complexes of HIV-1 induced by multimeric antibodies. Retrovirology 2014; 11:78. [PMID: 25274446 PMCID: PMC4193994 DOI: 10.1186/s12977-014-0078-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Accepted: 08/30/2014] [Indexed: 11/10/2022] Open
Abstract
Background Antibody mediated viral aggregation may impede viral transfer across mucosal surfaces by hindering viral movement in mucus, preventing transcytosis, or reducing inter-cellular penetration of epithelia thereby limiting access to susceptible mucosal CD4 T cells and dendritic cells. These functions may work together to provide effective immune exclusion of virus from mucosal tissue; however little is known about the antibody characteristics required to induce HIV aggregation. Such knowledge may be critical to the design of successful immunization strategies to facilitate viral immune exclusion at the mucosal portals of entry. Results The potential of neutralizing and non-neutralizing IgG and IgA monoclonals (mAbs) to induce HIV-1 aggregation was assessed by Dynamic light scattering (DLS). Although neutralizing and non-neutralizing IgG mAbs and polyclonal HIV-Ig efficiently aggregated soluble Env trimers, they were not capable of forming viral aggregates. In contrast, dimeric (but not monomeric) IgA mAbs induced stable viral aggregate populations that could be separated from uncomplexed virions. Epitope specificity influenced both the degree of aggregation and formation of higher order complexes by dIgA. IgA purified from serum of uninfected RV144 vaccine trial responders were able to efficiently opsonize viral particles in the absence of significant aggregation, reflective of monomeric IgA. Conclusions These results collectively demonstrate that dIgA is capable of forming stable viral aggregates providing a plausible basis for testing the effectiveness of aggregation as a potential protection mechanism at the mucosal portals of viral entry. Electronic supplementary material The online version of this article (doi:10.1186/s12977-014-0078-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Daniel J Stieh
- Center for Infection, Department of Cellular and Molecular Medicine, St George's, University of London, London, SW17 0RE, UK. .,Current address: Department of Cellular and Molecular Biology, Northwestern University, Feinberg School of Medicine, Chicago, IL, 60611, USA.
| | - Deborah F King
- Mucosal Infection & Immunity Group, Section of Infectious Diseases, Imperial College London, St Mary's Campus, London, W2 1PG, UK.
| | - Katja Klein
- Mucosal Infection & Immunity Group, Section of Infectious Diseases, Imperial College London, St Mary's Campus, London, W2 1PG, UK.
| | - Pinghuang Liu
- Duke Human Vaccine Center, Duke University Medical Center, Durham, NC, 27710, USA. .,Current address: Division of Swine Infectious Diseases, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin, 150001, China.
| | - Xiaoying Shen
- Duke Human Vaccine Center, Duke University Medical Center, Durham, NC, 27710, USA.
| | - Kwan Ki Hwang
- Duke Human Vaccine Center, Duke University Medical Center, Durham, NC, 27710, USA.
| | - Guido Ferrari
- Duke Human Vaccine Center, Duke University Medical Center, Durham, NC, 27710, USA.
| | - David C Montefiori
- Duke Human Vaccine Center, Duke University Medical Center, Durham, NC, 27710, USA.
| | - Barton Haynes
- Duke Human Vaccine Center, Duke University Medical Center, Durham, NC, 27710, USA.
| | | | | | | | | | - Nelson L Michael
- Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America.
| | - Merlin L Robb
- Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America.
| | - Jerome H Kim
- Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America.
| | - Thomas N Denny
- Duke Human Vaccine Center, Duke University Medical Center, Durham, NC, 27710, USA.
| | - Georgia D Tomaras
- Duke Human Vaccine Center, Duke University Medical Center, Durham, NC, 27710, USA.
| | - Robin J Shattock
- Mucosal Infection & Immunity Group, Section of Infectious Diseases, Imperial College London, St Mary's Campus, London, W2 1PG, UK.
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123
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Cryptic determinant of α4β7 binding in the V2 loop of HIV-1 gp120. PLoS One 2014; 9:e108446. [PMID: 25265384 PMCID: PMC4180765 DOI: 10.1371/journal.pone.0108446] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Accepted: 08/21/2014] [Indexed: 11/30/2022] Open
Abstract
The peptide segment of the second variable loop of HIV-1 spanning positions 166–181 harbors two functionally important sites. The first, spanning positions 179–181, engages the human α4β7 integrin receptor which is involved in T-cell gut-homing and may play a role in human immunodeficiency virus (HIV)-host cell interactions. The second, at positions 166–178, is a major target of anti-V2 antibodies elicited by the ALVAC/AIDSVAX vaccine used in the RV144 clinical trial. Notably, these two sites are directly adjacent, but do not overlap. Here, we report the identity of a second determinant of α4β7 binding located at positions 170–172 of the V2 loop. This segment – tripeptide QRV170–172– is located within the second site, yet functionally affects the first site. The absence of this segment abrogates α4β7 binding in peptides bearing the same sequence from position 173–185 as the V2 loops of the RV144 vaccines. However, peptides exhibiting V2 loop sequences from heterologous HIV-1 strains that include this QRV170–172 motif bind the α4β7 receptor on cells. Therefore, the peptide segment at positions 166–178 of the V2 loop of HIV-1 viruses appears to harbor a cryptic determinant of α4β7 binding. Prior studies show that the anti-V2 antibody response elicited by the RV144 vaccine, along with immune pressure inferred from a sieve analysis, is directed to this same region of the V2 loop. Accordingly, the anti-V2 antibodies that apparently reduced the risk of infection in the RV144 trial may have functioned by blocking α4β7-mediated HIV-host cell interactions via this cryptic determinant.
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124
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Valentin A, McKinnon K, Li J, Rosati M, Kulkarni V, Pilkington GR, Bear J, Alicea C, Vargas-Inchaustegui DA, Jean Patterson L, Pegu P, Liyanage NPM, Gordon SN, Vaccari M, Wang Y, Hogg AE, Frey B, Sui Y, Reed SG, Sardesai NY, Berzofsky JA, Franchini G, Robert-Guroff M, Felber BK, Pavlakis GN. Comparative analysis of SIV-specific cellular immune responses induced by different vaccine platforms in rhesus macaques. Clin Immunol 2014; 155:91-107. [PMID: 25229164 DOI: 10.1016/j.clim.2014.09.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 09/03/2014] [Accepted: 09/04/2014] [Indexed: 12/21/2022]
Abstract
To identify the most promising vaccine candidates for combinatorial strategies, we compared five SIV vaccine platforms including recombinant canary pox virus ALVAC, replication-competent adenovirus type 5 host range mutant RepAd, DNA, modified vaccinia Ankara (MVA), peptides and protein in distinct combinations. Three regimens used viral vectors (prime or boost) and two regimens used plasmid DNA. Analysis at necropsy showed that the DNA-based vaccine regimens elicited significantly higher cellular responses against Gag and Env than any of the other vaccine platforms. The T cell responses induced by most vaccine regimens disseminated systemically into secondary lymphoid tissues (lymph nodes, spleen) and effector anatomical sites (including liver, vaginal tissue), indicative of their role in viral containment at the portal of entry. The cellular and reported humoral immune response data suggest that combination of DNA and viral vectors elicits a balanced immunity with strong and durable responses able to disseminate into relevant mucosal sites.
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Affiliation(s)
- Antonio Valentin
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Katherine McKinnon
- FACS Core Facility, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Jinyao Li
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Margherita Rosati
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA
| | - Viraj Kulkarni
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Guy R Pilkington
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Jenifer Bear
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Candido Alicea
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA
| | - Diego A Vargas-Inchaustegui
- Immune Biology of Retroviral Infection Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - L Jean Patterson
- Immune Biology of Retroviral Infection Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Poonam Pegu
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Namal P M Liyanage
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Shari N Gordon
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Monica Vaccari
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Yichuan Wang
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Alison E Hogg
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Blake Frey
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Yongjun Sui
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Steven G Reed
- Infectious Diseases Research Institute, Seattle, WA, USA
| | | | - Jay A Berzofsky
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Genoveffa Franchini
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Marjorie Robert-Guroff
- Immune Biology of Retroviral Infection Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Barbara K Felber
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA.
| | - George N Pavlakis
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD, USA.
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125
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O'Connell RJ, Kim JH, Excler JL. The HIV-1 gp120 V1V2 loop: structure, function and importance for vaccine development. Expert Rev Vaccines 2014; 13:1489-500. [PMID: 25163695 DOI: 10.1586/14760584.2014.951335] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Although the second variable loop (V2) of the HIV-1 gp120 envelope glycoprotein shows substantial sequence diversity between strains, its functional importance imposes critical conservation of structure, and within particular microdomains, of sequence. V2 influences HIV-1 viral entry by contributing to trimer stabilization and co-receptor binding. It is one of 4 key domains targeted by the broadly neutralizing antibodies that arise during HIV-1 infection. HIV-1 uses V1V2 sequence variation and glycosylation to escape neutralizing antibody. In the Thai Phase III HIV-1 vaccine trial, RV144, vaccine-induced IgG against V1V2 inversely correlated with the risk of HIV-1 acquisition, and HIV-1 strains infecting RV144 vaccine recipients differed from those infecting placebo recipients in the V2 domain. Similarly, non-human primate challenge studies demonstrated an inverse correlation between vaccine-induced anti-V2 responses and simian immunodeficiency virus acquisition. We hypothesize that increased magnitude, frequency and duration of vaccine-induced anti-V2 antibody responses should improve efficacy afforded by pox-protein prime-boost HIV vaccine strategies.
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Affiliation(s)
- Robert J O'Connell
- Armed Forces Research Institute of Medical Sciences (AFRIMS), 315/6 Rajvithi Road, Bangkok 10400, Thailand
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126
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Jackson RJ, Worley M, Trivedi S, Ranasinghe C. Novel HIV IL-4R antagonist vaccine strategy can induce both high avidity CD8 T and B cell immunity with greater protective efficacy. Vaccine 2014; 32:5703-14. [PMID: 25151041 DOI: 10.1016/j.vaccine.2014.08.023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 05/07/2014] [Accepted: 08/11/2014] [Indexed: 12/18/2022]
Abstract
We have established that the efficacy of a heterologous poxvirus vectored HIV vaccine, fowlpox virus (FPV)-HIV gag/pol prime followed by attenuated vaccinia virus (VV)-HIV gag/pol booster immunisation, is strongly influenced by the cytokine milieu at the priming vaccination site, with endogenous IL-13 detrimental to the quality of the HIV specific CD8+ T cell response induced. We have now developed a novel HIV vaccine that co-expresses a C-terminal deletion mutant of the mouse IL-4, deleted for the essential tyrosine (Y119) required for signalling. In our vaccine system, the mutant IL-4C118 can bind to IL-4 type I and II receptors with high affinity, and transiently prevent the signalling of both IL-4 and IL-13 at the vaccination site. When this IL-4C118 adjuvanted vaccine was used in an intranasal rFPV/intramuscular rVV prime-boost immunisation strategy, greatly enhanced mucosal/systemic HIV specific CD8+ T cells with higher functional avidity, expressing IFN-γ, TNF-α and IL-2 and greater protective efficacy were detected. Surprisingly, the IL-4C118 adjuvanted vaccines also induced robust long-lived HIV gag-specific serum antibody responses, specifically IgG1 and IgG2a. The p55-gag IgG2a responses induced were of a higher magnitude relative to the IL-13Rα2 adjuvant vaccine. More interestingly, our recently tested IL-13Rα2 adjuvanted vaccine which only inhibited IL-13 activity, even though induced excellent high avidity HIV-specific CD8+ T cells, had a detrimental impact on the induction of gag-specific IgG2a antibody immunity. Our observations suggest that (i) IL-4 cell-signalling in the absence of IL-13 retarded gag-specific antibody isotype class switching, or (ii) IL-13Rα2 signalling was involved in inducing good gag-specific B cell immunity. Thus, we believe our novel IL-4R antagonist adjuvant strategy offers great promise not only for HIV-1 vaccines, but also against a range of chronic infections where sustained high quality mucosal and systemic T and B cell immunity are required for protection.
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Affiliation(s)
- Ronald J Jackson
- Molecular Mucosal Vaccine Immunology Group, Department of Immunology, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 0200, Australia
| | - Matthew Worley
- Molecular Mucosal Vaccine Immunology Group, Department of Immunology, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 0200, Australia
| | - Shubhanshi Trivedi
- Molecular Mucosal Vaccine Immunology Group, Department of Immunology, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 0200, Australia
| | - Charani Ranasinghe
- Molecular Mucosal Vaccine Immunology Group, Department of Immunology, The John Curtin School of Medical Research, The Australian National University, Canberra, ACT 0200, Australia.
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127
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Gartland AJ, Li S, McNevin J, Tomaras GD, Gottardo R, Janes H, Fong Y, Morris D, Geraghty DE, Kijak GH, Edlefsen PT, Frahm N, Larsen BB, Tovanabutra S, Sanders-Buell E, deCamp AC, Magaret CA, Ahmed H, Goodridge JP, Chen L, Konopa P, Nariya S, Stoddard JN, Wong K, Zhao H, Deng W, Maust BS, Bose M, Howell S, Bates A, Lazzaro M, O'Sullivan A, Lei E, Bradfield A, Ibitamuno G, Assawadarachai V, O'Connell RJ, deSouza MS, Nitayaphan S, Rerks-Ngarm S, Robb ML, Sidney J, Sette A, Zolla-Pazner S, Montefiori D, McElrath MJ, Mullins JI, Kim JH, Gilbert PB, Hertz T. Analysis of HLA A*02 association with vaccine efficacy in the RV144 HIV-1 vaccine trial. J Virol 2014; 88:8242-55. [PMID: 24829343 PMCID: PMC4135964 DOI: 10.1128/jvi.01164-14] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Accepted: 05/07/2014] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The RV144 HIV-1 vaccine trial demonstrated partial efficacy of 31% against HIV-1 infection. Studies into possible correlates of protection found that antibodies specific to the V1 and V2 (V1/V2) region of envelope correlated inversely with infection risk and that viruses isolated from trial participants contained genetic signatures of vaccine-induced pressure in the V1/V2 region. We explored the hypothesis that the genetic signatures in V1 and V2 could be partly attributed to selection by vaccine-primed T cells. We performed a T-cell-based sieve analysis of breakthrough viruses in the RV144 trial and found evidence of predicted HLA binding escape that was greater in vaccine versus placebo recipients. The predicted escape depended on class I HLA A*02- and A*11-restricted epitopes in the MN strain rgp120 vaccine immunogen. Though we hypothesized that this was indicative of postacquisition selection pressure, we also found that vaccine efficacy (VE) was greater in A*02-positive (A*02(+)) participants than in A*02(-) participants (VE = 54% versus 3%, P = 0.05). Vaccine efficacy against viruses with a lysine residue at site 169, important to antibody binding and implicated in vaccine-induced immune pressure, was also greater in A*02(+) participants (VE = 74% versus 15%, P = 0.02). Additionally, a reanalysis of vaccine-induced immune responses that focused on those that were shown to correlate with infection risk suggested that the humoral responses may have differed in A*02(+) participants. These exploratory and hypothesis-generating analyses indicate there may be an association between a class I HLA allele and vaccine efficacy, highlighting the importance of considering HLA alleles and host immune genetics in HIV vaccine trials. IMPORTANCE The RV144 trial was the first to show efficacy against HIV-1 infection. Subsequently, much effort has been directed toward understanding the mechanisms of protection. Here, we conducted a T-cell-based sieve analysis, which compared the genetic sequences of viruses isolated from infected vaccine and placebo recipients. Though we hypothesized that the observed sieve effect indicated postacquisition T-cell selection, we also found that vaccine efficacy was greater for participants who expressed HLA A*02, an allele implicated in the sieve analysis. Though HLA alleles have been associated with disease progression and viral load in HIV-1 infection, these data are the first to suggest the association of a class I HLA allele and vaccine efficacy. While these statistical analyses do not provide mechanistic evidence of protection in RV144, they generate testable hypotheses for the HIV vaccine community and they highlight the importance of assessing the impact of host immune genetics in vaccine-induced immunity and protection. (This study has been registered at ClinicalTrials.gov under registration no. NCT00223080.).
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Affiliation(s)
- Andrew J Gartland
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Sue Li
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - John McNevin
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Georgia D Tomaras
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | - Raphael Gottardo
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Holly Janes
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Youyi Fong
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Daryl Morris
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Daniel E Geraghty
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Gustavo H Kijak
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | - Paul T Edlefsen
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Nicole Frahm
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Brendan B Larsen
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | | | | | - Allan C deCamp
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Craig A Magaret
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Hasan Ahmed
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | | | - Lennie Chen
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Philip Konopa
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Snehal Nariya
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Julia N Stoddard
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Kim Wong
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Hong Zhao
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Wenjie Deng
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Brandon S Maust
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Meera Bose
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | - Shana Howell
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | - Adam Bates
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | - Michelle Lazzaro
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | | | - Esther Lei
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | - Andrea Bradfield
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | - Grace Ibitamuno
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | | | | | | | | | | | - Merlin L Robb
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | - John Sidney
- La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
| | - Alessandro Sette
- La Jolla Institute for Allergy and Immunology, La Jolla, California, USA
| | | | - David Montefiori
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | - M Juliana McElrath
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - James I Mullins
- Department of Microbiology, University of Washington, Seattle, Washington, USA
| | - Jerome H Kim
- U.S. Military HIV Research Program, Silver Spring, Maryland, USA
| | - Peter B Gilbert
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Tomer Hertz
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
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128
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Morales JF, Morin TJ, Yu B, Tatsuno GP, O'Rourke SM, Theolis R, Mesa KA, Berman PW. HIV-1 envelope proteins and V1/V2 domain scaffolds with mannose-5 to improve the magnitude and quality of protective antibody responses to HIV-1. J Biol Chem 2014; 289:20526-42. [PMID: 24872420 PMCID: PMC4110267 DOI: 10.1074/jbc.m114.554089] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Revised: 05/07/2014] [Indexed: 01/15/2023] Open
Abstract
Two lines of investigation have highlighted the importance of antibodies to the V1/V2 domain of gp120 in providing protection from HIV-1 infection. First, the recent RV144 HIV-1 vaccine trial documented a correlation between non-neutralizing antibodies to the V2 domain and protection. Second, multiple broadly neutralizing monoclonal antibodies to the V1/V2 domain (e.g. PG9) have been isolated from rare infected individuals, termed elite neutralizers. Interestingly, the binding of both types of antibodies appears to depend on the same cluster of amino acids (positions 167–171) adjacent to the junction of the B and C strands of the four-stranded V1/V2 domain β-sheet structure. However, the broadly neutralizing mAb, PG9, additionally depends on mannose-5 glycans at positions 156 and 160 for binding. Because the gp120 vaccine immunogens used in previous HIV-1 vaccine trials were enriched for complex sialic acid-containing glycans, and lacked the high mannose structures required for the binding of PG9-like mAbs, we wondered if these immunogens could be improved by limiting glycosylation to mannose-5 glycans. Here, we describe the PG9 binding activity of monomeric gp120s from multiple strains of HIV-1 produced with mannose-5 glycans. We also describe the properties of glycopeptide scaffolds from the V1/V2 domain also expressed with mannose-5 glycans. The V1/V2 scaffold from the A244 isolate was able to bind the PG9, CH01, and CH03 mAbs with high affinity provided that the proper glycans were present. We further show that immunization with A244 V1/V2 fragments alone, or in a prime/boost regimen with gp120, enhanced the antibody response to sequences in the V1/V2 domain associated with protection in the RV144 trial.
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Affiliation(s)
- Javier F. Morales
- From the Department of Biomolecular Engineering, Baskin School of Engineering, University of California at Santa Cruz, Santa Cruz, California 95064
| | - Trevor J. Morin
- From the Department of Biomolecular Engineering, Baskin School of Engineering, University of California at Santa Cruz, Santa Cruz, California 95064
| | - Bin Yu
- From the Department of Biomolecular Engineering, Baskin School of Engineering, University of California at Santa Cruz, Santa Cruz, California 95064
| | - Gwen P. Tatsuno
- From the Department of Biomolecular Engineering, Baskin School of Engineering, University of California at Santa Cruz, Santa Cruz, California 95064
| | - Sara M. O'Rourke
- From the Department of Biomolecular Engineering, Baskin School of Engineering, University of California at Santa Cruz, Santa Cruz, California 95064
| | - Richard Theolis
- From the Department of Biomolecular Engineering, Baskin School of Engineering, University of California at Santa Cruz, Santa Cruz, California 95064
| | - Kathryn A. Mesa
- From the Department of Biomolecular Engineering, Baskin School of Engineering, University of California at Santa Cruz, Santa Cruz, California 95064
| | - Phillip W. Berman
- From the Department of Biomolecular Engineering, Baskin School of Engineering, University of California at Santa Cruz, Santa Cruz, California 95064
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129
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Nonneutralizing functional antibodies: a new "old" paradigm for HIV vaccines. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2014; 21:1023-36. [PMID: 24920599 DOI: 10.1128/cvi.00230-14] [Citation(s) in RCA: 92] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Animal and human data from various viral infections and vaccine studies suggest that nonneutralizing antibodies (nNAb) without neutralizing activity in vitro may play an important role in protection against viral infection in vivo. This was illustrated by the recent human immunodeficiency virus (HIV) RV144 vaccine efficacy trial, which demonstrated that HIV-specific IgG-mediated nNAb directed against the V2 loop of HIV type 1 envelope (Env) were inversely correlated with risk for HIV acquisition, while Env-specific plasma IgA-mediated antibodies were directly correlated with risk. However, tier 1 NAb in the subset of responders with a low level of plasma Env-specific IgA correlated with decreased risk. Nonhuman primate simian immunodeficiency virus (SIV) and simian-human immunodeficiency virus (SHIV) challenge studies suggest that Env-mediated antibodies are essential and sufficient for protection. A comparison of immune responses generated in human efficacy trials reveals subtle differences in the fine specificities of the antibody responses, in particular in HIV-specific IgG subclasses. The underlying mechanisms that may have contributed to protection against HIV acquisition in humans, although not fully understood, are possibly mediated by antibody-dependent cell-mediated cytotoxicity (ADCC) and/or other nonneutralizing humoral effector functions, such as antibody-mediated phagocytosis. The presence of such functional nNAb in mucosal tissues and cervico-vaginal and rectal secretions challenges the paradigm that NAb are the predominant immune response conferring protection, although this does not negate the desirability of evoking neutralizing antibodies through vaccination. Instead, NAb and nNAb should be looked upon as complementary or synergistic humoral effector functions. Several HIV vaccine clinical trials to study these antibody responses in various prime-boost modalities in the systemic and mucosal compartments are ongoing. The induction of high-frequency HIV-specific functional nNAb at high titers may represent an attractive hypothesis-testing strategy in future HIV vaccine efficacy trials.
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130
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Vargas-Inchaustegui DA, Tuero I, Mohanram V, Musich T, Pegu P, Valentin A, Sui Y, Rosati M, Bear J, Venzon DJ, Kulkarni V, Alicea C, Pilkington GR, Liyanage NPM, Demberg T, Gordon SN, Wang Y, Hogg AE, Frey B, Patterson LJ, DiPasquale J, Montefiori DC, Sardesai NY, Reed SG, Berzofsky JA, Franchini G, Felber BK, Pavlakis GN, Robert-Guroff M. Humoral immunity induced by mucosal and/or systemic SIV-specific vaccine platforms suggests novel combinatorial approaches for enhancing responses. Clin Immunol 2014; 153:308-22. [PMID: 24907411 DOI: 10.1016/j.clim.2014.05.008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2014] [Revised: 05/13/2014] [Accepted: 05/21/2014] [Indexed: 12/22/2022]
Abstract
Combinatorial HIV/SIV vaccine approaches targeting multiple arms of the immune system might improve protective efficacy. We compared SIV-specific humoral immunity induced in rhesus macaques by five vaccine regimens. Systemic regimens included ALVAC-SIVenv priming and Env boosting (ALVAC/Env); DNA immunization; and DNA plus Env co-immunization (DNA&Env). RepAd/Env combined mucosal replication-competent Ad-env priming with systemic Env boosting. A Peptide/Env regimen, given solely intrarectally, included HIV/SIV peptides followed by MVA-env and Env boosts. Serum antibodies mediating neutralizing, phagocytic and ADCC activities were induced by ALVAC/Env, RepAd/Env and DNA&Env vaccines. Memory B cells and plasma cells were maintained in the bone marrow. RepAd/Env vaccination induced early SIV-specific IgA in rectal secretions before Env boosting, although mucosal IgA and IgG responses were readily detected at necropsy in ALVAC/Env, RepAd/Env, DNA&Env and DNA vaccinated animals. Our results suggest that combined RepAd priming with ALVAC/Env or DNA&Env regimen boosting might induce potent, functional, long-lasting systemic and mucosal SIV-specific antibodies.
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Affiliation(s)
- Diego A Vargas-Inchaustegui
- Immune Biology of Retroviral Infection Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Iskra Tuero
- Immune Biology of Retroviral Infection Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Venkatramanan Mohanram
- Immune Biology of Retroviral Infection Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Thomas Musich
- Immune Biology of Retroviral Infection Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Poonam Pegu
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Antonio Valentin
- Human Retrovirus Section, Vaccine Branch, CCR, NCI, NIH, Frederick, MD 21702, United States
| | - Yongjun Sui
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Margherita Rosati
- Human Retrovirus Section, Vaccine Branch, CCR, NCI, NIH, Frederick, MD 21702, United States
| | - Jenifer Bear
- Human Retrovirus Pathogenesis Section, Vaccine Branch, CCR, NCI, NIH, Frederick, MD 21702, United States
| | - David J Venzon
- Biostatistics and Data Management Section, CCR, NCI, NIH, Rockville, MD 20850, United States
| | - Viraj Kulkarni
- Human Retrovirus Pathogenesis Section, Vaccine Branch, CCR, NCI, NIH, Frederick, MD 21702, United States
| | - Candido Alicea
- Human Retrovirus Pathogenesis Section, Vaccine Branch, CCR, NCI, NIH, Frederick, MD 21702, United States
| | - Guy R Pilkington
- Human Retrovirus Pathogenesis Section, Vaccine Branch, CCR, NCI, NIH, Frederick, MD 21702, United States
| | - Namal P M Liyanage
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Thorsten Demberg
- Immune Biology of Retroviral Infection Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Shari N Gordon
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Yichuan Wang
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Alison E Hogg
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Blake Frey
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - L Jean Patterson
- Immune Biology of Retroviral Infection Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Janet DiPasquale
- Immune Biology of Retroviral Infection Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - David C Montefiori
- Duke Human Vaccine Institute and Department of Surgery, Duke University Medical Center, Durham, NC 27710, United States
| | | | - Steven G Reed
- Infectious Diseases Research Institute, Seattle, WA 98102, United States
| | - Jay A Berzofsky
- Molecular Immunogenetics and Vaccine Research Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Genoveffa Franchini
- Animal Models and Retroviral Vaccine Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States
| | - Barbara K Felber
- Human Retrovirus Pathogenesis Section, Vaccine Branch, CCR, NCI, NIH, Frederick, MD 21702, United States
| | - George N Pavlakis
- Human Retrovirus Section, Vaccine Branch, CCR, NCI, NIH, Frederick, MD 21702, United States
| | - Marjorie Robert-Guroff
- Immune Biology of Retroviral Infection Section, Vaccine Branch, CCR, NCI, NIH, Bethesda, MD 20892, United States.
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Rao M, Peachman KK, Kim J, Gao G, Alving CR, Michael NL, Rao VB. HIV-1 variable loop 2 and its importance in HIV-1 infection and vaccine development. Curr HIV Res 2014; 11:427-38. [PMID: 24191938 DOI: 10.2174/1570162x113116660064] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2013] [Revised: 05/24/2013] [Accepted: 06/13/2013] [Indexed: 12/30/2022]
Abstract
A vaccine that can prevent the transmission of HIV-1 at the site of exposure to the host is one of the best hopes to control the HIV-1 pandemic. The trimeric envelope spike consisting of heterodimers, gp120 and gp41, is essential for virus entry and thus has been a key target for HIV-1 vaccine development. However, it has been extremely difficult to identify the types of antibodies required to block the transmission of various HIV-1 strains and the immunogens that can elicit such antibodies due to the high genetic diversity of the HIV-1 envelope. The modest efficacy of the gp120 HIV-1 vaccine used in the RV144 Thai trial, including the studies on the immune correlates of protection, and the discovery of vaccine-induced immune responses to certain signature regions of the envelope have shown that the gp120 variable loop 2 (V2) is an important region. Since there is evidence that the V2 region interacts with the integrin α4β7 receptor of the host cell, and that this interaction might be important for virus capture, induction of antibodies against V2 loop could be postulated as one of the mechanisms to prevent the acquisition of HIV-1. Immunogens that can induce these antibodies should therefore be taken into consideration when designing HIV-1 vaccine formulations.
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Affiliation(s)
- Mangala Rao
- Laboratory of Adjuvant and Antigen Research, USMHRP at the Walter Reed Army Institute of Research, 503 Robert Grant Avenue, Rm 2A08, Sliver Spring, MD 20910, USA.
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132
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Felber BK, Valentin A, Rosati M, Bergamaschi C, Pavlakis GN. HIV DNA Vaccine: Stepwise Improvements Make a Difference. Vaccines (Basel) 2014; 2:354-79. [PMID: 26344623 PMCID: PMC4494255 DOI: 10.3390/vaccines2020354] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 04/11/2014] [Accepted: 04/18/2014] [Indexed: 12/15/2022] Open
Abstract
Inefficient DNA delivery methods and low expression of plasmid DNA have been major obstacles for the use of plasmid DNA as vaccine for HIV/AIDS. This review describes successful efforts to improve DNA vaccine methodology over the past ~30 years. DNA vaccination, either alone or in combination with other methods, has the potential to be a rapid, safe, and effective vaccine platform against AIDS. Recent clinical trials suggest the feasibility of its translation to the clinic.
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Affiliation(s)
- Barbara K Felber
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
| | - Antonio Valentin
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
| | - Margherita Rosati
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
| | - Cristina Bergamaschi
- Human Retrovirus Pathogenesis Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
| | - George N Pavlakis
- Human Retrovirus Section, Vaccine Branch, Center for Cancer Research, National Cancer Institute at Frederick, P.O. Box B, Frederick, MD 21702, USA.
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133
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HIV-1 vaccine-induced C1 and V2 Env-specific antibodies synergize for increased antiviral activities. J Virol 2014; 88:7715-26. [PMID: 24807721 DOI: 10.1128/jvi.00156-14] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The RV144 ALVAC/AIDSVax HIV-1 vaccine clinical trial showed an estimated vaccine efficacy of 31.2%. Viral genetic analysis identified a vaccine-induced site of immune pressure in the HIV-1 envelope (Env) variable region 2 (V2) focused on residue 169, which is included in the epitope recognized by vaccinee-derived V2 monoclonal antibodies. The ALVAC/AIDSVax vaccine induced antibody-dependent cellular cytotoxicity (ADCC) against the Env V2 and constant 1 (C1) regions. In the presence of low IgA Env antibody levels, plasma levels of ADCC activity correlated with lower risk of infection. In this study, we demonstrate that C1 and V2 monoclonal antibodies isolated from RV144 vaccinees synergized for neutralization, infectious virus capture, and ADCC. Importantly, synergy increased the HIV-1 ADCC activity of V2 monoclonal antibody CH58 at concentrations similar to that observed in plasma of RV144 vaccinees. These findings raise the hypothesis that synergy among vaccine-induced antibodies with different epitope specificities contributes to HIV-1 antiviral antibody responses and is important to induce for reduction in the risk of HIV-1 transmission. Importance: The Thai RV144 ALVAC/AIDSVax prime-boost vaccine efficacy trial represents the only example of HIV-1 vaccine efficacy in humans to date. Studies aimed at identifying immune correlates involved in the modest vaccine-mediated protection identified HIV-1 envelope (Env) variable region 2-binding antibodies as inversely correlated with infection risk, and genetic analysis identified a site of immune pressure within the region recognized by these antibodies. Despite this evidence, the antiviral mechanisms by which variable region 2-specific antibodies may have contributed to lower rates of infection remain unclear. In this study, we demonstrate that vaccine-induced HIV-1 envelope variable region 2 and constant region 1 antibodies synergize for recognition of virus-infected cells, infectious virion capture, virus neutralization, and antibody-dependent cellular cytotoxicity. This is a major step in understanding how these types of antibodies may have cooperatively contributed to reducing infection risk and should be considered in the context of prospective vaccine design.
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134
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Utachee P, Isarangkura-na-ayuthaya P, Tokunaga K, Ikuta K, Takeda N, Kameoka M. Impact of amino acid substitutions in the V2 and C2 regions of human immunodeficiency virus type 1 CRF01_AE envelope glycoprotein gp120 on viral neutralization susceptibility to broadly neutralizing antibodies specific for the CD4 binding site. Retrovirology 2014; 11:32. [PMID: 24758333 PMCID: PMC4003292 DOI: 10.1186/1742-4690-11-32] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Accepted: 04/09/2014] [Indexed: 01/15/2023] Open
Abstract
Background The CD4 binding site (CD4bs) of envelope glycoprotein (Env) gp120 is a functionally conserved, important target of anti-human immunodeficiency virus type 1 (HIV-1) neutralizing antibodies. Two neutralizing human monoclonal antibodies, IgG1 b12 (b12) and VRC01, are broadly reactive neutralizing antibodies which recognize conformational epitopes that overlap the CD4bs of Env gp120; however, many CRF01_AE viruses are resistant to neutralization mediated by these antibodies. We examined the mechanism underlying the b12 resistance of the viruses using CRF01_AE Env (AE-Env)-recombinant viruses in this study. Results Our results showed that an amino acid substitution at position 185 in the V2 region of gp120 played a crucial role in regulating the b12 susceptibility of AE-Env-recombinant viruses by cooperating with 2 previously reported potential N-linked glycosylation (PNLG) sites at positions 186 (N186) and 197 (N197) in the V2 and C2 regions of Env gp120. The amino acid residue at position 185 and 2 PNLG sites were responsible for the b12 resistance of 21 of 23 (>91%) AE-Env clones tested. Namely, the introduction of aspartic acid at position 185 (D185) conferred b12 susceptibility of 12 resistant AE-Env clones in the absence of N186 and/or N197, while the introduction of glycine at position 185 (G185) reduced the b12 susceptibility of 9 susceptible AE-Env clones in the absence of N186 and/or N197. In addition, these amino acid mutations altered the VRC01 susceptibility of many AE-Env clones. Conclusions We propose that the V2 and C2 regions of AE-Env gp120 contain the major determinants of viral resistance to CD4bs antibodies. CRF01_AE is a major circulating recombinant form of HIV-1 prevalent in Southeast Asia. Our data may provide important information to understand the molecular mechanism regulating the neutralization susceptibility of CRF01_AE viruses to CD4bs antibodies.
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Affiliation(s)
| | | | | | | | | | - Masanori Kameoka
- Thailand-Japan Research Collaboration Center on Emerging and Re-emerging Infections (RCC-ERI), Nonthaburi, Thailand.
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135
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Totrov M. Estimated secondary structure propensities within V1/V2 region of HIV gp120 are an important global antibody neutralization sensitivity determinant. PLoS One 2014; 9:e94002. [PMID: 24705879 PMCID: PMC3976368 DOI: 10.1371/journal.pone.0094002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Accepted: 03/10/2014] [Indexed: 11/22/2022] Open
Abstract
Background Neutralization sensitivity of HIV-1 virus to antibodies and anti-sera varies greatly between the isolates. Significant role of V1/V2 domain as a global neutralization sensitivity regulator has been suggested. Recent X-ray structures revealed presence of well-defined tertiary structure within this domain but also demonstrated partial disorder and conformational heterogeneity. Methods Correlations of neutralization sensitivity with the conformational propensities for beta-strand and alpha-helix formation over the entire folded V1/V2 domain as well as within sliding 5-residue window were investigated. Analysis was based on a set of neutralization data for 106 HIV isolates for which consistent neutralization sensitivity measurements against multiple pools of human immune sera have been previously reported. Results Significant correlation between beta-sheet formation propensity of the folded segments of V1/V2 domain and neutralization sensitivity was observed. Strongest correlation peaks localized to the beta-strands B and C. Correlation persisted when subsets of HIV isolates belonging to clades B, C and circulating recombinant form BC where analyzed individually or in combinations. Conclusions Observed correlations suggest that stability of the beta-sheet structure and/or degree of structural disorder in the V1/V2 domain is an important determinant of the global neutralization sensitivity of HIV-1 virus. While specific mechanism is to yet to be investigated, plausible hypothesis is that less ordered V1/V2s may have stronger masking effect on various neutralizing epitopes, perhaps effectively occupying larger volume and thereby occluding antibody access.
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Affiliation(s)
- Maxim Totrov
- Molsoft LLC, San Diego, California, United States of America
- * E-mail:
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136
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CD4-mimetic small molecules sensitize human immunodeficiency virus to vaccine-elicited antibodies. J Virol 2014; 88:6542-55. [PMID: 24696475 DOI: 10.1128/jvi.00540-14] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Approaches to prevent human immunodeficiency virus (HIV-1) transmission are urgently needed. Difficulties in eliciting antibodies that bind conserved epitopes exposed on the unliganded conformation of the HIV-1 envelope glycoprotein (Env) trimer represent barriers to vaccine development. During HIV-1 entry, binding of the gp120 Env to the initial receptor, CD4, triggers conformational changes in Env that result in the formation and exposure of the highly conserved gp120 site for interaction with the coreceptors, CCR5 and CXCR4. The DMJ compounds (+)-DMJ-I-228 and (+)-DMJ-II-121 bind gp120 within the conserved Phe 43 cavity near the CD4-binding site, block CD4 binding, and inhibit HIV-1 infection. Here we show that the DMJ compounds sensitize primary HIV-1, including transmitted/founder viruses, to neutralization by monoclonal antibodies directed against CD4-induced (CD4i) epitopes and the V3 region, two gp120 elements involved in coreceptor binding. Importantly, the DMJ compounds rendered primary HIV-1 sensitive to neutralization by antisera elicited by immunization of rabbits with HIV-1 gp120 cores engineered to assume the CD4-bound state. Thus, small molecules like the DMJ compounds may be useful as microbicides to inhibit HIV-1 infection directly and to sensitize primary HIV-1 to neutralization by readily elicited antibodies. IMPORTANCE Preventing HIV-1 transmission is a priority for global health. Eliciting antibodies that can neutralize many different strains of HIV-1 is difficult, creating problems for the development of a vaccine. We found that certain small-molecule compounds can sensitize HIV-1 to particular antibodies. These antibodies can be elicited in rabbits. 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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137
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Excler JL, Robb ML, Kim JH. HIV-1 vaccines: challenges and new perspectives. Hum Vaccin Immunother 2014; 10:1734-46. [PMID: 24637946 DOI: 10.4161/hv.28462] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The development of a safe and effective preventive HIV-1 vaccine remains a public health priority. Despite scientific difficulties and disappointing results, HIV-1 vaccine clinical development has, for the first time, established proof-of-concept efficacy against HIV-1 acquisition and identified vaccine-associated immune correlates of risk. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop correlated with decreased risk of HIV infection, while Env-specific IgA directly correlated with increased risk. The development of vaccine strategies such as improved envelope proteins formulated with potent adjuvants and DNA and vectors expressing mosaics, or conserved sequences, capable of eliciting greater breadth and depth of potentially relevant immune responses including neutralizing and non-neutralizing antibodies, CD4+ and CD8+ cell-mediated immune responses, mucosal immune responses, and immunological memory, is now proceeding quickly. Additional human efficacy trials combined with other prevention modalities along with sustained funding and international collaboration remain key to bring an HIV-1 vaccine to licensure.
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Affiliation(s)
- Jean-Louis Excler
- U.S. Military HIV Research Program; Division of Retrovirology; Walter Reed Army Institute of Research; Bethesda, MD USA; Henry M. Jackson Foundation for the Advancement of Military Medicine; Bethesda, MD USA
| | - Merlin L Robb
- U.S. Military HIV Research Program; Division of Retrovirology; Walter Reed Army Institute of Research; Bethesda, MD USA; Henry M. Jackson Foundation for the Advancement of Military Medicine; Bethesda, MD USA
| | - Jerome H Kim
- U.S. Military HIV Research Program; Division of Retrovirology; Walter Reed Army Institute of Research; Bethesda, MD USA
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138
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Abstract
PURPOSE OF REVIEW The genetic characterization of HIV-1 breakthrough infections in vaccine and placebo recipients offers new ways to assess vaccine efficacy trials. Statistical and sequence analysis methods provide opportunities to mine the mechanisms behind the effect of an HIV vaccine. RECENT FINDINGS The release of results from two HIV-1 vaccine efficacy trials, Step/HVTN-502 (HIV Vaccine Trials Network-502) and RV144, led to numerous studies in the last 5 years, including efforts to sequence HIV-1 breakthrough infections and compare viral characteristics between the vaccine and placebo groups. Novel genetic and statistical analysis methods uncovered features that distinguished founder viruses isolated from vaccinees from those isolated from placebo recipients, and identified HIV-1 genetic targets of vaccine-induced immune responses. SUMMARY Studies of HIV-1 breakthrough infections in vaccine efficacy trials can provide an independent confirmation to correlates of risk studies, as they take advantage of vaccine/placebo comparisons, whereas correlates of risk analyses are limited to vaccine recipients. Through the identification of viral determinants impacted by vaccine-mediated host immune responses, sieve analyses can shed light on potential mechanisms of vaccine protection.
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139
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Zolla-Pazner S, deCamp A, Gilbert PB, Williams C, Yates NL, Williams WT, Howington R, Fong Y, Morris DE, Soderberg KA, Irene C, Reichman C, Pinter A, Parks R, Pitisuttithum P, Kaewkungwal J, Rerks-Ngarm S, Nitayaphan S, Andrews C, O’Connell RJ, Yang ZY, Nabel GJ, Kim JH, Michael NL, Montefiori DC, Liao HX, Haynes BF, Tomaras GD. Vaccine-induced IgG antibodies to V1V2 regions of multiple HIV-1 subtypes correlate with decreased risk of HIV-1 infection. PLoS One 2014; 9:e87572. [PMID: 24504509 PMCID: PMC3913641 DOI: 10.1371/journal.pone.0087572] [Citation(s) in RCA: 221] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2013] [Accepted: 12/16/2013] [Indexed: 11/18/2022] Open
Abstract
UNLABELLED In the RV144 HIV-1 vaccine efficacy trial, IgG antibody (Ab) binding levels to variable regions 1 and 2 (V1V2) of the HIV-1 envelope glycoprotein gp120 were an inverse correlate of risk of HIV-1 infection. To determine if V1V2-specific Abs cross-react with V1V2 from different HIV-1 subtypes, if the nature of the V1V2 antigen used to asses cross-reactivity influenced infection risk, and to identify immune assays for upcoming HIV-1 vaccine efficacy trials, new V1V2-scaffold antigens were designed and tested. Protein scaffold antigens carrying the V1V2 regions from HIV-1 subtypes A, B, C, D or CRF01_AE were assayed in pilot studies, and six were selected to assess cross-reactive Abs in the plasma from the original RV144 case-control cohort (41 infected vaccinees, 205 frequency-matched uninfected vaccinees, and 40 placebo recipients) using ELISA and a binding Ab multiplex assay. IgG levels to these antigens were assessed as correlates of risk in vaccine recipients using weighted logistic regression models. Levels of Abs reactive with subtype A, B, C and CRF01_AE V1V2-scaffold antigens were all significant inverse correlates of risk (p-values of 0.0008-0.05; estimated odds ratios of 0.53-0.68 per 1 standard deviation increase). Thus, levels of vaccine-induced IgG Abs recognizing V1V2 regions from multiple HIV-1 subtypes, and presented on different scaffolds, constitute inverse correlates of risk for HIV-1 infection in the RV144 vaccine trial. The V1V2 antigens provide a link between RV144 and upcoming HIV-1 vaccine trials, and identify reagents and methods for evaluating V1V2 Abs as possible correlates of protection against HIV-1 infection. TRIAL REGISTRATION ClinicalTrials.gov NCT00223080.
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Affiliation(s)
- Susan Zolla-Pazner
- Department of Veterans Affairs New York Harbor Healthcare System, New York, New York, United States of America
- New York University School of Medicine, New York, New York, United States of America
- * E-mail:
| | - Allan deCamp
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Peter B. Gilbert
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Constance Williams
- New York University School of Medicine, New York, New York, United States of America
| | - Nicole L. Yates
- Duke University, Durham, North Carolina, United States of America
| | | | - Robert Howington
- Duke University, Durham, North Carolina, United States of America
| | - Youyi Fong
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Daryl E. Morris
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | | | - Carmela Irene
- Public Health Research Institute, University of Medicine and Dentistry, Newark, New Jersey, United States of America
| | - Charles Reichman
- Public Health Research Institute, University of Medicine and Dentistry, Newark, New Jersey, United States of America
| | - Abraham Pinter
- Public Health Research Institute, University of Medicine and Dentistry, Newark, New Jersey, United States of America
| | - Robert Parks
- Duke University, Durham, North Carolina, United States of America
| | | | | | | | | | - Charla Andrews
- Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Robert J. O’Connell
- Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Zhi-yong Yang
- Virology Laboratory, Vaccine Research Center, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Gary J. Nabel
- Virology Laboratory, Vaccine Research Center, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Jerome H. Kim
- Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Nelson L. Michael
- Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | | | - Hua-Xin Liao
- Duke University, Durham, North Carolina, United States of America
| | - Barton F. Haynes
- Duke University, Durham, North Carolina, United States of America
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Hanke T. Conserved immunogens in prime-boost strategies for the next-generation HIV-1 vaccines. Expert Opin Biol Ther 2014; 14:601-16. [PMID: 24490585 DOI: 10.1517/14712598.2014.885946] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
INTRODUCTION Effective vaccines are the best solution for stopping the spread of HIV/AIDS and other infectious diseases. Their development and in-depth understanding of pathogen-host interactions rely on technological advances. AREAS COVERED Rational vaccine development can be effectively approached by conceptual separation of, on one hand, design of immunogens from improving their presentation to the immune system and, on the other, induction of antibodies from induction of killer CD8(+) T cells. The biggest roadblock for many vaccines is the pathogens' variability. This is best tackled by focusing both antibodies and T cells on the functionally most conserved regions of proteins common to many variants, including escape mutants. For vectored vaccines, these 'universal' subunit immunogens are most efficiently delivered using heterologous prime-boost regimens, which can be further optimised by adjuvantation and route of delivery. EXPERT OPINION Development of vaccines against human diseases has many features in common. Acceleration of vaccine discovery depends on basic research and new technologies. Novel strategies should be safely, but rapidly tested in humans. While out-of-the-box thinking is important, vaccine success largely depends on incremental advances best achieved through small, systematic, iterative clinical studies. Failures are inevitable, but the end rewards are huge. The future will be exciting.
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Affiliation(s)
- Tomáš Hanke
- The Jenner Institute, University of Oxford , Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ , UK
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141
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Functional implications of the binding mode of a human conformation-dependent V2 monoclonal antibody against HIV. J Virol 2014; 88:4100-12. [PMID: 24478429 DOI: 10.1128/jvi.03153-13] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
UNLABELLED Data from the RV144 HIV vaccine trial indicated that gp120 V2 antibodies were associated with a lower risk of infection; thus, the mapping of V2 epitopes can contribute to the design of an effective HIV vaccine. We solved the crystal structure of human monoclonal antibody (MAb) 2158, which targets a conformational V2 epitope overlapping the α4β7 integrin binding site, and constructed a full-length model of V1V2. Comparison of computational energy stability to experimental enzyme-linked immunosorbent assay (ELISA) results identified a hydrophobic core that stabilizes the V2 region for optimal 2158 binding, as well as residues that directly mediate side chain interactions with MAb 2158. These data define the binding surface recognized by MAb 2158 and offer a structural explanation for why a mismatched mutation at position 181 (I181X) in the V2 loop was associated with a higher vaccine efficiency in the RV144 clinical vaccine trial. IMPORTANCE Correlate analysis of the RV144 HIV-1 vaccine trial suggested that the presence of antibodies to the second variable region (V2) of HIV-1 gp120 was responsible for the modest protection observed in the trial. V2 is a highly variable and immunogenic region, and structural information on its antigenic landscape will be important for rational design of an effective HIV-1 vaccine. Using X-ray crystallography, computational design tools, and mutagenesis assays, we carried out a detailed and systematic investigation of the epitope recognition of human V2 MAb 2158 and demonstrated that its epitope region overlaps the integrin binding site within V2. In addition, we propose a structure-based mechanism for mismatching of the isoleucine at position 181 and the increased vaccine efficacy seen in the RV144 vaccine trial.
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142
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Zhang J, Alam SM, Bouton-Verville H, Chen Y, Newman A, Stewart S, Jaeger FH, Montefiori DC, Dennison SM, Haynes BF, Verkoczy L. Modulation of nonneutralizing HIV-1 gp41 responses by an MHC-restricted TH epitope overlapping those of membrane proximal external region broadly neutralizing antibodies. THE JOURNAL OF IMMUNOLOGY 2014; 192:1693-706. [PMID: 24465011 DOI: 10.4049/jimmunol.1302511] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A goal of HIV-1 vaccine development is to elicit broadly neutralizing Abs (BnAbs), but current immunization strategies fail to induce BnAbs, and for unknown reasons, often induce nonneutralizing Abs instead. To explore potential host genetic contributions controlling Ab responses to the HIV-1 Envelope, we have used congenic strains to identify a critical role for MHC class II restriction in modulating Ab responses to the membrane proximal external region (MPER) of gp41, a key vaccine target. Immunized H-2(d)-congenic strains had more rapid, sustained, and elevated MPER(+) Ab titers than those bearing other haplotypes, regardless of immunogen, adjuvant, or prime or boost regimen used, including formulations designed to provide T cell help. H-2(d)-restricted MPER(+) serum Ab responses depended on CD4 TH interactions with class II (as revealed in immunized intra-H-2(d/b) congenic or CD154(-/-) H-2(d) strains, and by selective abrogation of MPER restimulated, H-2(d)-restricted primed splenocytes by class II-blocking Abs), and failed to neutralize HIV-1 in the TZM-b/l neutralization assay, coinciding with lack of specificity for an aspartate residue in the neutralization core of BnAb 2F5. Unexpectedly, H-2(d)-restricted MPER(+) responses functionally mapped to a core TH epitope partially overlapping the 2F5/z13/4E10 BnAb epitopes as well as nonneutralizing B cell-Ab binding residues. We propose that class II restriction contributes to the general heterogeneity of nonneutralizing gp41 responses induced by Envelope. Moreover, the proximity of TH and B cell epitopes in this restriction may have to be considered in redesigning minimal MPER immunogens aimed at exclusively binding BnAb epitopes and triggering MPER(+) BnAbs.
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Affiliation(s)
- Jinsong Zhang
- Duke Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710
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143
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Silencing sexually transmitted infections: topical siRNA-based interventions for the prevention of HIV and HSV. Infect Dis Obstet Gynecol 2014; 2014:125087. [PMID: 24526828 PMCID: PMC3913465 DOI: 10.1155/2014/125087] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Accepted: 11/25/2013] [Indexed: 12/27/2022] Open
Abstract
The global impact of sexually transmitted infections (STIs) is significant. The sexual transmission of viruses such as herpes simplex virus type-2 (HSV-2) and the human immunodeficiency virus type-1 (HIV-1), has been especially difficult to control. To date, no effective vaccines have been developed to prevent the transmission of these STIs. Although antiretroviral drugs have been remarkably successful in treating the symptoms associated with these viral infections, the feasibility of their widespread use for prevention purposes may be more limited. Microbicides might provide an attractive alternative option to reduce their spread. In particular, topically applied small inhibitory RNAs (siRNAs) have been shown to not only block transmission of viral STIs to mucosal tissues both in vitro and in vivo, but also confer durable knockdown of target gene expression, thereby circumventing the need to apply a microbicide around the time of sexual encounter, when compliance is mostly difficult. Despite numerous clinical trials currently testing the efficacy of siRNA-based therapeutics, they have yet to be approved for use in the treatment of viral STIs. While several obstacles to their successful implementation in the clinic still exist, promising preclinical studies suggest that siRNAs are a viable modality for the future prevention and treatment of HSV and HIV.
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144
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Goepfert PA, Elizaga ML, Seaton K, Tomaras GD, Montefiori DC, Sato A, Hural J, DeRosa SC, Kalams SA, McElrath MJ, Keefer MC, Baden LR, Lama JR, Sanchez J, Mulligan MJ, Buchbinder SP, Hammer SM, Koblin BA, Pensiero M, Butler C, Moss B, Robinson HL. Specificity and 6-month durability of immune responses induced by DNA and recombinant modified vaccinia Ankara vaccines expressing HIV-1 virus-like particles. J Infect Dis 2014; 210:99-110. [PMID: 24403557 DOI: 10.1093/infdis/jiu003] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Clade B DNA and recombinant modified vaccinia Ankara (MVA) vaccines producing virus-like particles displaying trimeric membrane-bound envelope glycoprotein (Env) were tested in a phase 2a trial in human immunodeficiency virus (HIV)-uninfected adults for safety, immunogenicity, and 6-month durability of immune responses. METHODS A total of 299 individuals received 2 doses of JS7 DNA vaccine and 2 doses of MVA/HIV62B at 0, 2, 4, and 6 months, respectively (the DDMM regimen); 3 doses of MVA/HIV62B at 0, 2, and 6 months (the MMM regimen); or placebo injections. RESULTS At peak response, 93.2% of the DDMM group and 98.4% of the MMM group had binding antibodies for Env. These binding antibodies were more frequent and of higher magnitude for the transmembrane subunit (gp41) than the receptor-binding subunit (gp120) of Env. For both regimens, response rates were higher for CD4(+) T cells (66.4% in the DDMM group and 43.1% in the MMM group) than for CD8(+) T cells (21.8% in the DDMM group and 14.9% in the MMM group). Responding CD4(+) and CD8(+) T cells were biased toward Gag, and >70% produced 2 or 3 of the 4 cytokines evaluated (ie, interferon γ, interleukin 2, tumor necrosis factor α, and granzyme B). Six months after vaccination, the magnitudes of antibodies and T-cell responses had decreased by <3-fold. CONCLUSIONS DDMM and MMM vaccinations with virus-like particle-expressing immunogens elicited durable antibody and T-cell responses.
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Affiliation(s)
| | - Marnie L Elizaga
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center
| | - Kelly Seaton
- Laboratory for AIDS Vaccine Research and Development, Department of Surgery, Duke University Medical Center, Durham, North Carolina
| | - Georgia D Tomaras
- Laboratory for AIDS Vaccine Research and Development, Department of Surgery, Duke University Medical Center, Durham, North Carolina
| | - David C Montefiori
- Laboratory for AIDS Vaccine Research and Development, Department of Surgery, Duke University Medical Center, Durham, North Carolina
| | - Alicia Sato
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center
| | - John Hural
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center
| | - Stephen C DeRosa
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center University of Washington, Seattle, Washington
| | - Spyros A Kalams
- Vanderbilt University School of Medicine, Nashville, Tennessee
| | - M Juliana McElrath
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center University of Washington, Seattle, Washington
| | - Michael C Keefer
- University of Rochester School of Medicine and Dentistry, Rochester
| | - Lindsey R Baden
- Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Javier R Lama
- Asociacion Civil IMPACTA Salud y Educacion, Lima, Peru
| | - Jorge Sanchez
- Asociacion Civil IMPACTA Salud y Educacion, Lima, Peru
| | | | | | | | | | | | | | - Bernard Moss
- Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland
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145
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Affiliation(s)
- Mathilde Krim
- The Foundation for AIDS Research, New York, New York
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146
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Tager AM, Pensiero M, Allen TM. Recent advances in humanized mice: accelerating the development of an HIV vaccine. J Infect Dis 2013; 208 Suppl 2:S121-4. [PMID: 24151317 DOI: 10.1093/infdis/jit451] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Recent advances in the development of humanized mice hold great promise to advance our understanding of protective immunity to human immunodeficiency virus (HIV) infection and to aid in the design of an effective HIV vaccine. This supplement of the Journal of Infectious Diseases summarizes work in the humanized mouse model presented at an HIV Humanized Mouse workshop in Boston, Massachusetts, in November 2012, including recent advances in the development of humanized mice, the trafficking of human immune cells following mucosal HIV transmission, the role of immune activation and Toll-like receptor agonists in the control of HIV, the induction and efficacy of HIV-specific cellular and humoral immune responses, and the preclinical modeling of novel anti-HIV therapeutics. Many gaps remain in our understanding of how to design an effective HIV vaccine and novel therapeutics to eliminate the viral reservoir. Promising early results from studies in humanized mice suggest great potential and enthusiasm for this model to accelerate these critical areas of HIV research.
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Affiliation(s)
- Andrew M Tager
- Center for Immunology and Inflammatory Diseases, Division of Rheumatology, Allergy and Immunology, Massachusetts General Hospital, Harvard Medical School
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147
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Enhanced fusion and virion incorporation for HIV-1 subtype C envelope glycoproteins with compact V1/V2 domains. J Virol 2013; 88:2083-94. [PMID: 24335304 DOI: 10.1128/jvi.02308-13] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
In infected people, the HIV-1 envelope glycoprotein (Env) constantly evolves to escape the immune response while retaining the essential elements needed to mediate viral entry into target cells. The extensive genetic variation of Env is particularly striking in the V1/V2 hypervariable domains. In this study, we investigated the trade-off, in terms of fusion efficiency, for encoding V1/V2 domains of different lengths. We found that natural variations in V1/V2 length exert a profound impact on HIV-1 entry. Variants encoding compact V1/V2 domains mediated fusion with higher efficiencies than related Envs encoding longer V1/V2 domains. By exchanging the V1/V2 domains between Envs of the same infected person or between two persons linked by a transmission event, we further demonstrated that V1/V2 domains critically influence both Env incorporation into viral particles and fusion to primary CD4 T cells and monocyte-derived dendritic cells. Shortening the V1/V2 domains consistently increased Env incorporation and fusion, whereas lengthening the V1/V2 domains decreased Env incorporation and fusion. Given that in a new host transmitted founder viruses are distinguished by compact Envs with fewer glycosylation sites, our study points to fusion and possibly Env incorporation into virions as limiting steps for transmission of HIV-1 to a new host and suggests that the length and/or the N-glycosylation profile of the V1/V2 domain influences these early steps in the HIV life cycle.
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148
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Pre-clinical development of a recombinant, replication-competent adenovirus serotype 4 vector vaccine expressing HIV-1 envelope 1086 clade C. PLoS One 2013; 8:e82380. [PMID: 24312658 PMCID: PMC3849430 DOI: 10.1371/journal.pone.0082380] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 10/26/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND There is a well-acknowledged need for an effective AIDS vaccine that protects against HIV-1 infection or limits in vivo viral replication. The objective of these studies is to develop a replication-competent, vaccine vector based on the adenovirus serotype 4 (Ad4) virus expressing HIV-1 envelope (Env) 1086 clade C glycoprotein. Ad4 recombinant vectors expressing Env gp160 (Ad4Env160), Env gp140 (Ad4Env140), and Env gp120 (Ad4Env120) were evaluated. METHODS The recombinant Ad4 vectors were generated with a full deletion of the E3 region of Ad4 to accommodate the env gene sequences. The vaccine candidates were assessed in vitro following infection of A549 cells for Env-specific protein expression and for posttranslational transport to the cell surface as monitored by the binding of broadly neutralizing antibodies (bNAbs). The capacity of the Ad4Env vaccines to induce humoral immunity was evaluated in rabbits for Env gp140 and V1V2-specific binding antibodies, and HIV-1 pseudovirus neutralization. Mice immunized with the Ad4Env160 vaccine were assessed for IFNγ T cell responses specific for overlapping Env peptide sets. RESULTS Robust Env protein expression was confirmed by western blot analysis and recognition of cell surface Env gp160 by multiple bNAbs. Ad4Env vaccines induced humoral immune responses in rabbits that recognized Env 1086 gp140 and V1V2 polypeptide sequences derived from 1086 clade C, A244 clade AE, and gp70 V1V2 CASE A2 clade B fusion protein. The immune sera efficiently neutralized tier 1 clade C pseudovirus MW965.26 and neutralized the homologous and heterologous tier 2 pseudoviruses to a lesser extent. Env-specific T cell responses were also induced in mice following Ad4Env160 vector immunization. CONCLUSIONS The Ad4Env vaccine vectors express high levels of Env glycoprotein and induce both Env-specific humoral and cellular immunity thus supporting further development of this new Ad4 HIV-1 Env vaccine platform in Phase 1 clinical trials.
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149
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Figueiredo S, Charmeteau B, Surenaud M, Salmon D, Launay O, Guillet JG, Hosmalin A, Gahery H. Memory CD8(+) T cells elicited by HIV-1 lipopeptide vaccines display similar phenotypic profiles but differences in term of magnitude and multifunctionality compared with FLU- or EBV-specific memory T cells in humans. Vaccine 2013; 32:492-501. [PMID: 24291199 DOI: 10.1016/j.vaccine.2013.11.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 10/19/2013] [Accepted: 11/15/2013] [Indexed: 11/16/2022]
Abstract
Differentiation marker, multifunctionality and magnitude analyses of specific-CD8(+) memory T cells are crucial to improve development of HIV vaccines designed to generate cell-mediated immunity. Therefore, we fully characterized the HIV-specific CD8(+) T cell responses induced in volunteers vaccinated with HIV lipopeptide vaccines for phenotypic markers, tetramer staining, cytokine secretion, and cytotoxic activities. The frequency of ex vivo CD8(+) T cells elicited by lipopeptide vaccines is very rare and central-memory phenotype and functions of these cells were been shown to be important in AIDS immunity. So, we expanded them using specific peptides to compare the memory T cell responses induced in volunteers by HIV vaccines with responses to influenza (FLU) or Epstein Barr virus (EBV). By analyzing the differentiation state of IFN-γ-secreting CD8(+) T cells, we found a CCR7(-)CD45RA(-)CD28(+int)/CD28(-) profile (>85%) belonging to a subset of intermediate-differentiated effector T cells for HIV, FLU, and EBV. We then assessed the quality of the response by measuring various T cell functions. The percentage of single IFN-γ T cell producers in response to HIV was 62% of the total of secreting T cells compared with 35% for FLU and EBV, dual and triple (IFN-γ/IL-2/CD107a) T cell producers could also be detected but at lower levels (8% compared with 37%). Finally, HIV-specific T cells secreted IFN-γ and TNF-α, but not the dual combination like FLU- and EBV-specific T cells. Thus, we found that the functional profile and magnitude of expanded HIV-specific CD8(+) T precursors were more limited than those of to FLU- and EBV-specific CD8(+) T cells. These data show that CD8(+) T cells induced by these HIV vaccines have a similar differentiation profile to FLU and EBV CD8(+) T cells, but that the vaccine potency to induce multifunctional T cells needs to be increased in order to improve vaccination strategies.
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Affiliation(s)
- Suzanne Figueiredo
- Inserm U1016, Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Univ Paris Descartes, Paris, France
| | - Benedicte Charmeteau
- Inserm U1016, Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Univ Paris Descartes, Paris, France
| | - Mathieu Surenaud
- Inserm U1016, Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Univ Paris Descartes, Paris, France
| | - Dominique Salmon
- Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Cochin, Paris, France
| | - Odile Launay
- Inserm CIC BT505, CIC de Vaccinologie Cochin Pasteur, Paris, France
| | - Jean-Gérard Guillet
- Inserm U1016, Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Univ Paris Descartes, Paris, France
| | - Anne Hosmalin
- Inserm U1016, Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Cochin, Paris, France
| | - Hanne Gahery
- Inserm U1016, Institut Cochin, Paris, France; CNRS UMR8104, Paris, France; Univ Paris Descartes, Paris, France; Institut National de Santé et de Recherche Médicale, INSERM U976, Saint-Louis Hospital, Skin Research Center, 75010 Paris, France; Paris Diderot University, Sorbonne Paris Cité, Laboratory of Immunology, Dermatology & Oncology, UMR-S 976, 75010 Paris, France.
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150
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Imholte GC, Sauteraud R, Korber B, Bailer RT, Turk ET, Shen X, Tomaras GD, Mascola JR, Koup RA, Montefiori DC, Gottardo R. A computational framework for the analysis of peptide microarray antibody binding data with application to HIV vaccine profiling. J Immunol Methods 2013; 395:1-13. [PMID: 23770318 PMCID: PMC3999921 DOI: 10.1016/j.jim.2013.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Revised: 04/26/2013] [Accepted: 06/01/2013] [Indexed: 10/26/2022]
Abstract
We present an integrated analytical method for analyzing peptide microarray antibody binding data, from normalization through subject-specific positivity calls and data integration and visualization. Current techniques for the normalization of such data sets do not account for non-specific binding activity. A novel normalization technique based on peptide sequence information quickly and effectively reduced systematic biases. We also employed a sliding mean window technique that borrows strength from peptides sharing similar sequences, resulting in reduced signal variability. A smoothed signal aided in the detection of weak antibody binding hotspots. A new principled FDR method of setting positivity thresholds struck a balance between sensitivity and specificity. In addition, we demonstrate the utility and importance of using baseline control measurements when making subject-specific positivity calls. Data sets from two human clinical trials of candidate HIV-1 vaccines were used to validate the effectiveness of our overall computational framework.
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Affiliation(s)
- Greg C. Imholte
- Vaccine and Infectious Disease Division, Fred Hutchinson
Cancer Research Center, 1100 Fairview Avenue North, M2-C200, PO Box 19024, Seattle,
WA 98109-1024
- Department of Statistics, University of Washington Box
354322, Seattle, WA 98195-4322
| | - Renan Sauteraud
- Vaccine and Infectious Disease Division, Fred Hutchinson
Cancer Research Center, 1100 Fairview Avenue North, M2-C200, PO Box 19024, Seattle,
WA 98109-1024
| | - Bette Korber
- Theoretical Biology and Biophysics, Los Alamos National
Laboratory, Los Alamos, New Mexico
- Santa Fe Institute, Santa Fe, New Mexico
| | - Robert T. Bailer
- Vaccine Research Center, National Institute of Allergy and
Infectious Diseases, National Institutes of Health Bethesda, MD 20892
| | - Ellen T. Turk
- Vaccine Research Center, National Institute of Allergy and
Infectious Diseases, National Institutes of Health Bethesda, MD 20892
| | - Xiaoying Shen
- Duke Human Vaccine Institute, Duke University Medical
Center, Durham, NC 27710
| | - Georgia D. Tomaras
- Duke Human Vaccine Institute, Duke University Medical
Center, Durham, NC 27710
| | - John R. Mascola
- Vaccine Research Center, National Institute of Allergy and
Infectious Diseases, National Institutes of Health Bethesda, MD 20892
| | - Richard A. Koup
- Vaccine Research Center, National Institute of Allergy and
Infectious Diseases, National Institutes of Health Bethesda, MD 20892
| | - David C. Montefiori
- Duke Human Vaccine Institute, Duke University Medical
Center, Durham, NC 27710
| | - Raphael Gottardo
- Vaccine and Infectious Disease Division, Fred Hutchinson
Cancer Research Center, 1100 Fairview Avenue North, M2-C200, PO Box 19024, Seattle,
WA 98109-1024
- Department of Statistics, University of Washington Box
354322, Seattle, WA 98195-4322
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