1
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Moyo-Gwete T, Ayres F, Mzindle NB, Makhado Z, Manamela NP, Richardson SI, Kitchin D, van Graan S, van Heerden J, Parbhoo N, Chege GK, Moore PL. Evaluating the antibody response elicited by diverse HIV envelope immunogens in the African green monkey (Vervet) model. Sci Rep 2024; 14:13311. [PMID: 38858452 PMCID: PMC11164991 DOI: 10.1038/s41598-024-63703-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 05/31/2024] [Indexed: 06/12/2024] Open
Abstract
African Green (Vervet) monkeys have been extensively studied to understand the pathogenesis of infectious diseases. Using vervet monkeys as pre-clinical models may be an attractive option for low-resourced areas as they are found abundantly and their maintenance is more cost-effective than bigger primates such as rhesus macaques. We assessed the feasibility of using vervet monkeys as animal models to examine the immunogenicity of HIV envelope trimer immunogens in pre-clinical testing. Three groups of vervet monkeys were subcutaneously immunized with either the BG505 SOSIP.664 trimer, a novel subtype C SOSIP.664 trimer, CAP255, or a combination of BG505, CAP255 and CAP256.SU SOSIP.664 trimers. All groups of vervet monkeys developed robust binding antibodies by the second immunization with the peak antibody response occurring after the third immunization. Similar to binding, antibody dependent cellular phagocytosis was also observed in all the monkeys. While all animals developed potent, heterologous Tier 1 neutralizing antibody responses, autologous neutralization was limited with only half of the animals in each group developing responses to their vaccine-matched pseudovirus. These data suggest that the vervet monkey model may yield distinct antibody responses compared to other models. Further study is required to further determine the utility of this model in HIV immunization studies.
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Affiliation(s)
- Thandeka Moyo-Gwete
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa.
| | - Frances Ayres
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Nonkululeko B Mzindle
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Zanele Makhado
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Nelia P Manamela
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Simone I Richardson
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Dale Kitchin
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Strauss van Graan
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Joritha van Heerden
- Primate Unit and Delft Animal Centre, Centre and Platform Office, South African Medical Research Council, Cape Town, South Africa
| | - Nishal Parbhoo
- Department of Life and Consumer Sciences, College of Agriculture and Environmental Sciences, University of South Africa, Johannesburg, South Africa
| | - Gerald K Chege
- Primate Unit and Delft Animal Centre, Centre and Platform Office, South African Medical Research Council, Cape Town, South Africa
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - Penny L Moore
- SA MRC Antibody Immunity Research Unit, School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
- Centre for HIV and STIs, National Institute or Communicable Diseases (NICD) of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), Durban, South Africa
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2
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Torralba J, de la Arada I, Partida-Hanon A, Rujas E, Arribas M, Insausti S, Valotteau C, Valle J, Andreu D, Caaveiro JMM, Jiménez MA, Apellániz B, Redondo-Morata L, Nieva JL. Molecular recognition of a membrane-anchored HIV-1 pan-neutralizing epitope. Commun Biol 2022; 5:1265. [DOI: 10.1038/s42003-022-04219-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 11/03/2022] [Indexed: 11/19/2022] Open
Abstract
AbstractAntibodies against the carboxy-terminal section of the membrane-proximal external region (C-MPER) of the HIV-1 envelope glycoprotein (Env) are considered as nearly pan-neutralizing. Development of vaccines capable of producing analogous broadly neutralizing antibodies requires deep understanding of the mechanism that underlies C-MPER recognition in membranes. Here, we use the archetypic 10E8 antibody and a variety of biophysical techniques including single-molecule approaches to study the molecular recognition of C-MPER in membrane mimetics. In contrast to the assumption that an interfacial MPER helix embodies the entire C-MPER epitope recognized by 10E8, our data indicate that transmembrane domain (TMD) residues contribute to binding affinity and specificity. Moreover, anchoring to membrane the helical C-MPER epitope through the TMD augments antibody binding affinity and relieves the effects exerted by the interfacial MPER helix on the mechanical stability of the lipid bilayer. These observations support that addition of TMD residues may result in more efficient and stable anti-MPER vaccines.
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3
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Cattin M, Bruxelle JF, Ng K, Blaukopf M, Pantophlet R, Kosma P. Synthetic neoglycoconjugates of hepta- and nonamannoside ligands for eliciting oligomannose-specific HIV-1-neutralizing antibodies. Chembiochem 2022; 23:e202200061. [PMID: 35104013 PMCID: PMC9108342 DOI: 10.1002/cbic.202200061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 02/01/2022] [Indexed: 11/08/2022]
Abstract
Oligomannose-type glycans on the spike protein of HIV-1 constitute relevant epitopes to elicit broadly neutralizing antibodies (bnAbs). Herein we describe an improved synthesis of α- and β-linked hepta- and nonamannosyl ligands that, subsequently, were converted into BSA and CRM 197 neoglycoconjugates. We assembled the ligands from anomeric 3-azidopropyl spacer glycosides from select 3-O-protected thiocresyl mannoside donors. Chain extensions were achieved using 4+3 or 4+5 block synthesis of thiocresyl and trichloroacetimidate glycosyl donors. Subsequent global deprotection generated the 3-aminopropyl oligosaccharide ligands. ELISA binding data obtained with the β-anomeric hepta- and nonamannosyl conjugates with a selection of HIV-1 bnAbs showed comparable binding of both mannosyl ligands by Fab fragments yet lesser binding of the nonasaccharide conjugate by the corresponding IgG antibodies. These results support previous observations that a complete Man 9 structure might not be the preferred antigenic binding motif for some oligomannose-specific antibodies and have implications for glycoside designs to elicit oligomannose-targeted HIV-1-neutralizing antibodies.
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Affiliation(s)
- Matteo Cattin
- University of Natural Resources and Life Sciences: Universitat fur Bodenkultur Wien, Chemistry, Muthgasse 18, A 1190, Vienna, AUSTRIA
| | - Jean-François Bruxelle
- Simon Fraser University Faculty of Health Sciences, Molecular Biology and Biochemistry, Burnaby, CANADA
| | - Kurtis Ng
- Simon Fraser University Faculty of Health Sciences, Molecular Biology and Biochemistry, CANADA
| | - Markus Blaukopf
- University of Natural Resources and Life Sciences Vienna: Universitat fur Bodenkultur Wien, Chemistry, AUSTRIA
| | - Ralph Pantophlet
- Simon Fraser University Faculty of Health Sciences, Molecular Biology and Biochemistry, V5A 1S6, Burnaby, CANADA
| | - Paul Kosma
- University of Natural Resources and Life Sciences, Chemistry, Muthgasse 18, A 1190, Vienna, AUSTRIA
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4
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Kariuki SM, Selhorst P, Abrahams MR, Rebe K, Williamson C, Dorfman JR. Neutralization sensitivity of genital tract HIV-1: shift in selective milieu shapes the population available to transmit. AIDS 2021; 35:1365-1373. [PMID: 33831907 DOI: 10.1097/qad.0000000000002912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Previous studies indicate that transmitted/founder HIV-1 isolates are sensitive to neutralization by the transmitting donor's antibodies. This is true in at least a subset of sexual transmissions. We investigated whether this selection for neutralization-sensitive variants begins in the genital tract of the donor, prior to transmission. DESIGN Laboratory study. METHODS HIV-1 viruses from semen and blood of two male donors living with HIV-1 were tested for neutralization sensitivity to contemporaneous autologous antibodies. RESULTS In one donor, semen-derived clones (n = 10, geometric mean ID50 = 176) were 1.75-fold [95% confidence interval (CI) 1.11-2.76, P = 0.018] more sensitive than blood-derived clones (n = 12, geometric mean ID50 = 111) to the individual's own contemporaneous neutralizing antibodies. Enhanced overall neutralization sensitivity of the semen-derived clones could not explain the difference because these semen-derived isolates showed a trend of being less sensitive to neutralization by a pool of heterologous clade-matched sera. This relative sensitivity of semen-derived clones was not observed in a second donor who did not exhibit obvious independent HIV-1 replication in the genital tract. A Bayesian analysis suggested that the set of semen sequences that we analysed originated from a blood sequence. CONCLUSION In some instances, selection for neutralization-sensitive variants during HIV-1 transmission begins in the genital tract of the donor and this may be driven by independent HIV-1 replication in this compartment. Thus, a shift in the selective milieu in the male genital tract allows outgrowth of neutralization-sensitive HIV-1 variants, shaping the population of isolates available for transmission to a new host.
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Affiliation(s)
- Samuel Mundia Kariuki
- Division of Immunology, Department of Pathology, University of Cape Town
- International Centre for Genetic Engineering and Biotechnology, Cape Town, Cape Town, South Africa
- Department of Biological Sciences, School of Science, University of Eldoret, Kenya
| | - Philippe Selhorst
- Division of Medical Virology, Department of Pathology, and Institute of Infectious Diseases and Molecular Medicine, University of Cape Town
| | - Melissa-Rose Abrahams
- Division of Medical Virology, Department of Pathology, and Institute of Infectious Diseases and Molecular Medicine, University of Cape Town
| | - Kevin Rebe
- ANOVA Health Institute, Cape Town
- Division of Infectious Diseases and HIV Medicine, Department of Medicine, University of Cape Town
| | - Carolyn Williamson
- Division of Medical Virology, Department of Pathology, and Institute of Infectious Diseases and Molecular Medicine, University of Cape Town
| | - Jeffrey R Dorfman
- Division of Immunology, Department of Pathology, University of Cape Town
- Division of Medical Virology, Department of Pathology, University of Stellenbosch, Cape Town, South Africa
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5
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Marcelino R, Gramacho F, Martin F, Brogueira P, Janeiro N, Afonso C, Badura R, Valadas E, Mansinho K, Caldeira L, Taveira N, Marcelino JM. Antibody response against selected epitopes in the HIV-1 envelope gp41 ectodomain contributes to reduce viral burden in HIV-1 infected patients. Sci Rep 2021; 11:8993. [PMID: 33903642 PMCID: PMC8076315 DOI: 10.1038/s41598-021-88274-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 04/09/2021] [Indexed: 01/26/2023] Open
Abstract
The ectodomain of gp41 is the target of potent binding and neutralizing antibodies (NAbs) and is being explored in new strategies for antibody-based HIV vaccines. Previous studies have suggested that the W164A-3S (3S) and EC26-2A4 (EC26) peptides located in the gp41 ectodomain may be potential HIV vaccine candidates. We assessed 3S- and EC26-specific binding antibody responses and related neutralizing activity in a large panel of chronic HIV-1-infected Portuguese individuals on ART. A similar proportion of participants had antibodies binding to 3S (9.6%) and EC26 (9.9%) peptides but the level of reactivity against 3S was significantly higher compared to EC26, except in the rare patients with double peptide reactivity. The higher antigenicity of 3S was unrelated with disease stage, as assessed by CD4+ T cell counts, but it was directly related with plasma viral load. Most patients that were tested (89.9%, N = 268) showed tier 1 neutralizing activity, the potency being inversely associated with plasma viral load. In the subset of patients that were tested for neutralization of tier 2 isolates, neutralization breadth was inversely correlated with plasma viral load and directly correlated with CD4+ T cell counts. These results are consistent with a role for neutralizing antibodies in controlling viral replication and preventing the decline of CD4+ T lymphocytes. Importantly, in patients with 3S-specific antibodies, neutralizing titers were inversely correlated with viral RNA levels and proviral DNA levels. Moreover, patients with 3S and/or EC26-specific antibodies showed a 1.9-fold higher tier 2 neutralization score than patients without antibodies suggesting that 3S and/or EC26-specific antibodies contribute to neutralization breadth and potency in HIV-1 infected patients. Overall, these results suggest that antibodies targeting the S3 and EC26 epitopes may contribute to reduce viral burden and provide further support for the inclusion of 3S and EC26 epitopes in HIV-1 vaccine candidates.
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Affiliation(s)
- Rute Marcelino
- Global Health and Tropical Medicine-GHTM, Instituto de Higiene e Medicina Tropical-IHMT, Universidade Nova de Lisboa-UNL, 1349-008, Lisboa, Portugal.,Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, 1649-003, Lisboa, Portugal.,Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz, Monte de Caparica, 2829-511, Monte de Caparica, Portugal
| | - Filipa Gramacho
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal
| | - Francisco Martin
- Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, 1649-003, Lisboa, Portugal
| | - Pedro Brogueira
- Serviço de Doenças Infeciosas, Hospital Egas Moniz-HEM, Centro Hospitalar Lisboa Ocidental-CHLO, E.P.E., Lisboa, 1349-019, Lisboa, Portugal
| | - Nuno Janeiro
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Claudia Afonso
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Robert Badura
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Emília Valadas
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Kamal Mansinho
- Serviço de Doenças Infeciosas, Hospital Egas Moniz-HEM, Centro Hospitalar Lisboa Ocidental-CHLO, E.P.E., Lisboa, 1349-019, Lisboa, Portugal
| | - Luís Caldeira
- Hospital de Santa Maria-HSM, Centro Hospitalar Lisboa Norte-CHLN, E.P.E., Lisboa, 1649-028, Lisboa, Portugal.,Clínica Universitária de Doenças Infeciosas, Faculdade de Medicina, Universidade de Lisboa-UL, Lisboa, 1649-028, Lisboa, Portugal
| | - Nuno Taveira
- Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, 1649-003, Lisboa, Portugal.,Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz, Monte de Caparica, 2829-511, Monte de Caparica, Portugal
| | - José M Marcelino
- Global Health and Tropical Medicine-GHTM, Instituto de Higiene e Medicina Tropical-IHMT, Universidade Nova de Lisboa-UNL, 1349-008, Lisboa, Portugal. .,Instituto de Investigação do Medicamento (iMed.ULisboa), Faculdade de Farmácia, Universidade de Lisboa, Lisboa, 1649-003, Lisboa, Portugal. .,Centro de Investigação Interdisciplinar Egas Moniz (CiiEM), Instituto Universitário Egas Moniz, Monte de Caparica, 2829-511, Monte de Caparica, Portugal.
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6
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Moyo T, Guleid FH, Schomaker M, Williamson C, Dorfman JR. HIV-1 Subtype C Tier 3 Viruses Have Increased Infectivity Compared to Tier 2 Viruses. AIDS Res Hum Retroviruses 2020; 36:1010-1019. [PMID: 32935560 DOI: 10.1089/aid.2020.0124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
A primary concern of an antibody-based HIV-1 therapy is the virus' ability to rapidly escape antibody responses. Therefore, we investigated the relationships between antibody neutralization sensitivity, viral phenotype, and infectivity in 13 subtype C viruses using a HeLa transfectant-based assay. We observed that the seven tier 3 viruses exhibited higher infectivity than the tier 2 viruses, suggesting that higher neutralization resistance did not have a substantial entry cost. There was no relationship between neutralization resistance and susceptibility to entry inhibitors Maraviroc, PSC RANTES, or the fusion inhibitor T20, indicating that neutralization resistance may not alter these inhibitor target sites. By analyzing glycosylation patterns in 82 subtype C viruses, we found that the presence of an N-linked glycan motif at position N413 and its absence at N332 were the most important predictors of neutralization resistance. In a set of 200 subtype C viruses, tier 3 strains were more resistant than tier 2 or 1B viruses to several broadly neutralizing monoclonal antibodies targeting three different epitopes. This suggests that it is unlikely that resistance to antibodies targeting a single epitope drives overall resistance. In the context of an antibody-based intervention, highly resistant viruses with increased infectivity, circulating in the population, could hinder HIV-1 control since entry of tier 3 viruses is not always selected against. Therefore, for any long-term antibody-based intervention to be globally relevant, it must elicit responses that limit the occurrence of resistance.
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Affiliation(s)
- Thandeka Moyo
- Division of Immunology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- International Centre for Genetic Engineering and Biotechnology, Cape Town, South Africa
| | - Fatuma H. Guleid
- Division of Immunology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- International Centre for Genetic Engineering and Biotechnology, Cape Town, South Africa
| | - Michael Schomaker
- Centre for Infectious Disease Epidemiology and Research, University of Cape Town, Cape Town, South Africa
| | - Carolyn Williamson
- Division of Medical Virology and Institute of Infectious Disease and Molecular Medicine, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- National Health Laboratory Service, Cape Town, South Africa
| | - Jeffrey R. Dorfman
- Division of Immunology, Department of Pathology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Division of Medical Virology, Department of Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
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7
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Selection and immune recognition of HIV-1 MPER mimotopes. Virology 2020; 550:99-108. [PMID: 32980676 DOI: 10.1016/j.virol.2020.06.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 05/20/2020] [Accepted: 06/26/2020] [Indexed: 11/20/2022]
Abstract
The membrane proximal external region (MPER) of HIV-1 gp41 is targeted by several neutralizing antibodies (NAbs) and is of interest for vaccine design. In this study, we identified novel MPER peptide mimotopes and evaluated their reactivity with HIV + plasma antibodies to characterize the diversity of the immune responses to MPER during natural infection. We utilized phage display technology to generate novel mimotopes that fit antigen-binding sites of MPER NAbs 4E10, 2F5 and Z13. Plasma antibodies from 10 HIV + patients were mapped by phage immunoprecipitation, to identify unique patient MPER binding profiles that were distinct from, and overlapping with, those of MPER NAbs. 4E10 mimotope binding profiles correlated with plasma neutralization of HIV-2/HIV-1 MPER chimeric virus, and with overall plasma neutralization breadth and potency. When administered as vaccines, 4E10 mimotopes elicited low titer NAb responses in mice. HIV mimotopes may be useful for detailed analysis of plasma antibody specificity.
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8
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Torralba J, de la Arada I, Carravilla P, Insausti S, Rujas E, Largo E, Eggeling C, Arrondo JLR, Apellániz B, Nieva JL. Cholesterol Constrains the Antigenic Configuration of the Membrane-Proximal Neutralizing HIV-1 Epitope. ACS Infect Dis 2020; 6:2155-2168. [PMID: 32584020 DOI: 10.1021/acsinfecdis.0c00243] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The envelope glycoprotein (Env) enables HIV-1 cell entry through fusion of host-cell and viral membranes induced by the transmembrane subunit gp41. Antibodies targeting the C-terminal sequence of the membrane-proximal external region (C-MPER) block the fusogenic activity of gp41 and achieve neutralization of divergent HIV-1 strains and isolates. Thus, recreating the structure that generates broadly neutralizing C-MPER antibodies during infection is a major goal in HIV vaccine development. Here, we have reconstituted a peptide termed CpreTM-TMD in a membrane environment. This peptide contains the C-MPER epitope and the minimum TMD residues required for the anchorage of the Env glycoprotein to the viral membrane. In addition, we have used antibody 10E8 variants to gauge the antigenic configuration attained by CpreTM-TMD as a function of the membrane cholesterol content, a functional determinant of the HIV envelope and liposome-based vaccines. Differential binding of the 10E8 variants and the trend of the IgG responses recovered from rabbits immunized with liposome-peptide formulations, suggested that cholesterol may restrict 10E8 accessibility to the C-MPER epitope. Our data ruled out the destabilization of the lipid bilayer architecture in CpreTM-TMD-containing membranes, and pointed to the perturbation of the helical conformation by lipid packing as the cause of the antigenic configuration loss induced by cholesterol. Overall, our results provide additional insights into the structural basis of the Env complex anchoring to membranes, and suggest new approaches to the design of effective immunogens directed against the near pan-neutralizing HIV-1 epitope C-MPER.
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Affiliation(s)
- Johana Torralba
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
| | - Igor de la Arada
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
| | - Pablo Carravilla
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Institute of Applied Optics and Biophysics, Friedrich-Schiller-University Jena, Max-Wien Platz 1, 07743 Jena, Germany
- Leibniz Institute of Photonic Technology e.V., Albert-Einstein-Straße 9, 07745 Jena, Germany
| | - Sara Insausti
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
| | - Edurne Rujas
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
| | - Eneko Largo
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Department of Immunology, Microbiology and Parasitology, Medicine and Odontology Faculty, University of Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
| | - Christian Eggeling
- Institute of Applied Optics and Biophysics, Friedrich-Schiller-University Jena, Max-Wien Platz 1, 07743 Jena, Germany
- Leibniz Institute of Photonic Technology e.V., Albert-Einstein-Straße 9, 07745 Jena, Germany
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Headley Way, OX3 9DS Oxford, U.K
| | - José L R Arrondo
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
| | - Beatriz Apellániz
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Department of Physiology, Faculty of Pharmacy, University of the Basque Country (UPV/EHU), Paseo de la Universidad, 7, 01006 Vitoria-Gasteiz, Spain
| | - José L Nieva
- Biofisika Institute (CSIC, UPV/EHU), University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
- Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), PO Box 644, 48080 Bilbao, Spain
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9
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Bruxelle JF, Kirilenko T, Qureshi Q, Lu N, Trattnig N, Kosma P, Pantophlet R. Serum alpha-mannosidase as an additional barrier to eliciting oligomannose-specific HIV-1-neutralizing antibodies. Sci Rep 2020; 10:7582. [PMID: 32371950 PMCID: PMC7200719 DOI: 10.1038/s41598-020-64500-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/15/2020] [Indexed: 01/04/2023] Open
Abstract
Oligomannose-type glycans on HIV-1 gp120 form a patch that is targeted by several broadly neutralizing antibodies (bnAbs) and that therefore is of interest to vaccine design. However, attempts to elicit similar oligomannose-specific bnAbs by immunizing with oligomannosidic glycoconjugates have only been modestly successful so far. A common assumption is that eliciting oligomannose-specific bnAbs is hindered by B cell tolerance, resulting from the presented oligomannosides being sensed as self molecules. Here, we present data, along with existing scientific evidence, supporting an additional, or perhaps alternate, explanation: serum mannosidase trimming of the presented oligomannosides in vivo. Mannosidase trimming lessens the likelihood of eliciting antibodies with capacity to bind full-sized oligomannose, which typifies the binding mode of existing bnAbs to the oligomannose patch. The rapidity of the observed trimming suggests the need for immunization strategies and/or synthetic glycosides that readily avoid or resist mannosidase trimming upon immunization and can overcome possible tolerance restrictions.
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Affiliation(s)
- Jean-François Bruxelle
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada
| | - Tess Kirilenko
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada
- AbCellera Biologics Inc., Vancouver, British Columbia, Canada
| | - Quratulain Qureshi
- Department of Molecular Biology & Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada
| | - Naiomi Lu
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada
| | - Nino Trattnig
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, A-1190, Austria
- Department of Chemical Biology and Drug Discovery, Utrecht University, Utrecht, The Netherlands
| | - Paul Kosma
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, A-1190, Austria
| | - Ralph Pantophlet
- Faculty of Health Sciences, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada.
- Department of Molecular Biology & Biochemistry, Simon Fraser University, Burnaby, British Columbia, V5A1S6, Canada.
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10
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Moyo T, Kitchin D, Moore PL. Targeting the N332-supersite of the HIV-1 envelope for vaccine design. Expert Opin Ther Targets 2020; 24:499-509. [PMID: 32340497 DOI: 10.1080/14728222.2020.1752183] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Introduction: Broadly neutralizing antibodies (bNAbs) that are able to target diverse global viruses are widely believed to be crucial for an HIV-1 vaccine. Several conserved targets recognized by these antibodies have been identified on the HIV-1 envelope glycoprotein. One such target that shows particular promise for vaccination is the N332-supersite.Areas covered: This review describes the potential of the N332-supersite epitope as an immunogen design platform. We discuss the structure of the epitope and the bNAbs that target it, emphasizing their diverse modes of binding. Furthermore, the successes and limitations of recent N332-supersite immunization studies are discussed.Expert opinion: During HIV-1 infection, some of the broadest and most potent bNAbs target the N332-supersite. Furthermore, some of these antibodies require less affinity maturation than the high levels typical of many bNAbs, making these potentially more achievable vaccine targets. In addition, bNAbs bind this epitope with multiple angles of approach and glycan dependencies, perhaps increasing the probability of eliciting such responses by vaccination. Animal studies have shown that N332-supersite bNAb precursors can be activated by novel immunogens. While follow-up studies must establish whether boosting strategies can drive the maturation of bNAbs from these precursors, the development of targeted N332-supersite immunogens expands our arsenal of potential HIV-1 vaccine candidates.
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Affiliation(s)
- Thandeka Moyo
- Centre for HIV-1 and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa.,Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Dale Kitchin
- Centre for HIV-1 and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa.,Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Penny L Moore
- Centre for HIV-1 and STIs, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa.,Antibody Immunity Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.,Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu Natal, Durban, South Africa
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11
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Soleymani S, Hadi A, Asgari F, Haghighipour N, Bolhassani A. Combination of Mechanical and Chemical Methods Improves Gene Delivery in Cell-based HIV Vaccines. Curr Drug Deliv 2020; 16:818-828. [PMID: 31549593 DOI: 10.2174/1567201816666190923152914] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 06/27/2019] [Accepted: 08/06/2019] [Indexed: 12/21/2022]
Abstract
OBJECTIVE Novel vaccination approaches are required to control human immunodeficiency virus (HIV) infections. The membrane proximal external region (MPER) of Env gp41 subunit and the V3/glycans of Env gp120 subunit were known as potential antigenic targets for anti-HIV-1 vaccines. In this study, we prepared the modified dendritic cells (DCs) and mesenchymal stem cells (MSCs) with HIV-1 MPER-V3 gene using mechanical and chemical approaches. METHODS At first, MPER-V3 fusion DNA delivery was optimized in dendritic cells (DCs) and mesenchymal stem cells (MSCs) using three mechanical (i.e., uniaxial cyclic stretch, equiaxial cyclic stretch and shear stress bioreactors), and two chemical (i.e., TurboFect or Lipofectamine) methods. Next, the modified DCs and MSCs with MPER-V3 antigen were compared to induce immune responses in vivo. RESULTS Our data showed that the combination of equiaxial cyclic stretch loading and lipofectamine twice with 48 h intervals increased the efficiency of transfection about 60.21 ± 1.05 % and 65.06 ± 0.09 % for MSCs and DCs, respectively. Moreover, DCs and MSCs transfected with MPER-V3 DNA in heterologous DC or MSC prime/ peptide boost immunizations induced high levels of IgG2a, IgG2b, IFN-γ and IL-10 directed toward Th1 responses as well as an increased level of Granzyme B. Indeed, the modified MSCs and DCs with MPER-V3 DNA could significantly enhance the MPER/V3-specific T-cell responses compared to MPER/V3 peptide immunization. CONCLUSIONS These findings showed that the modified MSC-based immunization could elicit effective immune responses against HIV antigen similar to the modified DC-based immunization.
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Affiliation(s)
- Sepehr Soleymani
- Department of Hepatitis and AIDs, Pasteur Institute of Iran, Tehran, Iran
| | - Amin Hadi
- National Cell Bank of Iran, Pasteur Institute of Iran, Tehran, Iran
| | - Fatemeh Asgari
- National Cell Bank of Iran, Pasteur Institute of Iran, Tehran, Iran
| | | | - Azam Bolhassani
- Department of Hepatitis and AIDs, Pasteur Institute of Iran, Tehran, Iran
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12
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Kariuki SM, Selhorst P, Norman J, Cohen K, Rebe K, Williamson C, Dorfman JR. Detectable HIV-1 in semen in individuals with very low blood viral loads. Virol J 2020; 17:29. [PMID: 32138741 PMCID: PMC7059658 DOI: 10.1186/s12985-020-01300-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 02/20/2020] [Indexed: 12/17/2022] Open
Abstract
Background Several reports indicate that a portion (5–10%) of men living with HIV-1 intermittently shed HIV-1 RNA into seminal plasma while on long term effective antiretroviral therapy (ART). This is highly suggestive of an HIV-1 reservoir in the male genital tract. However, the status of this reservoir in men living with HIV-1 who are not under treatment is underexplored and has implications for understanding the origins and evolution of the reservoir. Finding Forty-three HIV-1 positive, antiretroviral therapy naïve study participants attending a men’s health clinic were studied. Semen viral loads and blood viral loads were generally correlated, with semen viral loads generally detected in individuals with blood viral loads > 10,000 cp/ml. However, we found 1 individual with undetectable viral loads (<20cp/ml) and 2 individuals with very low blood viral load (97 and 333cp/ml), but with detectable HIV-1 in semen (485–1157 copies/semen sample). Blood viral loads in the first individual were undetectable when tested three times over the prior 5 years. Conclusions Semen HIV-1 viral loads are usually related to blood viral loads, as we confirm. Nonetheless, this was not true in a substantial minority of individuals suggesting unexpectedly high levels of replication in the male genital tract in a few individuals, despite otherwise effective immune control. This may reflect establishment of a local reservoir of HIV-1 populations.
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Affiliation(s)
- Samuel Mundia Kariuki
- Division of Immunology, Department of Pathology, University of Cape Town, Anzio Rd, Observatory, Cape Town, 7925, South Africa.,International Centre for Genetic Engineering and Biotechnology, Cape Town, South Africa.,Department of Biological Sciences, School of Science, University of Eldoret, Eldoret, Kenya
| | - Philippe Selhorst
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town, South Africa.,Virology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
| | - Jennifer Norman
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Karen Cohen
- Division of Clinical Pharmacology, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Kevin Rebe
- Anova Health Institute, Cape Town, South Africa.,Division of Infectious Diseases and HIV Medicine, Department of Medicine, University of Cape Town, Cape Town, South Africa
| | - Carolyn Williamson
- Division of Medical Virology, Department of Pathology, University of Cape Town, Cape Town, South Africa.,Institute for Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa.,National Health Laboratory Service, Johannesburg, South Africa
| | - Jeffrey R Dorfman
- Division of Immunology, Department of Pathology, University of Cape Town, Anzio Rd, Observatory, Cape Town, 7925, South Africa. .,Division of Virology, Faculty of Medicine and Health Sciences, Stellenbosch University, Parow, South Africa.
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13
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Pinto D, Fenwick C, Caillat C, Silacci C, Guseva S, Dehez F, Chipot C, Barbieri S, Minola A, Jarrossay D, Tomaras GD, Shen X, Riva A, Tarkowski M, Schwartz O, Bruel T, Dufloo J, Seaman MS, Montefiori DC, Lanzavecchia A, Corti D, Pantaleo G, Weissenhorn W. Structural Basis for Broad HIV-1 Neutralization by the MPER-Specific Human Broadly Neutralizing Antibody LN01. Cell Host Microbe 2019; 26:623-637.e8. [PMID: 31653484 PMCID: PMC6854463 DOI: 10.1016/j.chom.2019.09.016] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/29/2019] [Accepted: 09/27/2019] [Indexed: 11/24/2022]
Abstract
Potent and broadly neutralizing antibodies (bnAbs) are the hallmark of HIV-1 protection by vaccination. The membrane-proximal external region (MPER) of the HIV-1 gp41 fusion protein is targeted by the most broadly reactive HIV-1 neutralizing antibodies. Here, we examine the structural and molecular mechansims of neutralization by anti-MPER bnAb, LN01, which was isolated from lymph-node-derived germinal center B cells of an elite controller and exhibits broad neutralization breadth. LN01 engages both MPER and the transmembrane (TM) region, which together form a continuous helix in complex with LN01. The tilted TM orientation allows LN01 to interact simultaneously with the peptidic component of the MPER epitope and membrane via two specific lipid binding sites of the antibody paratope. Although LN01 carries a high load of somatic mutations, most key residues interacting with the MPER epitope and lipids are germline encoded, lending support for the LN01 epitope as a candidate for lineage-based vaccine development. bNAb LN01 neutralizes 92% of a 118-strain virus panel LN01 targets the HIV-1 gp41 MPER, the TM region, and lipids LN01-complexed MPER forms a continuous helix with TM Most LN01 paratope residues interacting with MPER-TM and lipids are germline encoded
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Affiliation(s)
- Dora Pinto
- Institute for Research in Biomedicine, Bellinzona 6500, Ticino, Switzerland
| | - Craig Fenwick
- Swiss Vaccine Research Institute, Lausanne University Hospital, University of Lausanne, 1011 Lausanne, Switzerland
| | - Christophe Caillat
- Institut de Biologie Structurale (IBS), University Grenoble Alpes, CEA, CNRS, 38000 Grenoble, France
| | - Chiara Silacci
- Institute for Research in Biomedicine, Bellinzona 6500, Ticino, Switzerland
| | - Serafima Guseva
- Institut de Biologie Structurale (IBS), University Grenoble Alpes, CEA, CNRS, 38000 Grenoble, France
| | - François Dehez
- LPCT, UMR 7019 Université de Lorraine CNRS, 54500 Vandœuvre-lès-Nancy, France; Laboratoire International Associé CNRS and University of Illinois at Urbana-Champaign, LPCT, UMR 7019 Universiteé de Lorraine CNRS, Vandœuvre-lès-Nancy 54500, France
| | - Christophe Chipot
- LPCT, UMR 7019 Université de Lorraine CNRS, 54500 Vandœuvre-lès-Nancy, France; Laboratoire International Associé CNRS and University of Illinois at Urbana-Champaign, LPCT, UMR 7019 Universiteé de Lorraine CNRS, Vandœuvre-lès-Nancy 54500, France; Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Sonia Barbieri
- Institute for Research in Biomedicine, Bellinzona 6500, Ticino, Switzerland
| | - Andrea Minola
- Humabs Biomed SA, Vir Biotechnology, 6500 Bellinzona, Ticino, Switzerland
| | - David Jarrossay
- Institute for Research in Biomedicine, Bellinzona 6500, Ticino, Switzerland
| | - Georgia D Tomaras
- Duke Human Vaccine Institute, Durham, NC 27710, USA; Paris Diderot University, Sorbonne Paris Cité, Paris 75013, France
| | | | - Agostino Riva
- Department of Biomedical and Clinical Sciences, Luigi Sacco University Hospital, Università di Milano, 20157 Milan, Italy; III Division of Infectious Diseases, ASST Fatebenefratelli-Sacco, 20157 Milan, Italy
| | - Maciej Tarkowski
- Department of Biomedical and Clinical Sciences, Luigi Sacco University Hospital, Università di Milano, 20157 Milan, Italy
| | - Olivier Schwartz
- Institut Pasteur, Virus & Immunity Unit, CNRS UMR 3569, Paris 75015, France; Vaccine Research Institute, 94000 Créteil, France
| | - Timothée Bruel
- Institut Pasteur, Virus & Immunity Unit, CNRS UMR 3569, Paris 75015, France; Vaccine Research Institute, 94000 Créteil, France
| | - Jérémy Dufloo
- Institut Pasteur, Virus & Immunity Unit, CNRS UMR 3569, Paris 75015, France; Vaccine Research Institute, 94000 Créteil, France; Paris Diderot University, Sorbonne Paris Cité, Paris 75013, France
| | - Michael S Seaman
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - David C Montefiori
- Department of Surgery, Duke University Medical Center, Durham, NC 27710, USA
| | | | - Davide Corti
- Humabs Biomed SA, Vir Biotechnology, 6500 Bellinzona, Ticino, Switzerland.
| | - Giuseppe Pantaleo
- Swiss Vaccine Research Institute, Lausanne University Hospital, University of Lausanne, 1011 Lausanne, Switzerland; Service of Immunology and Allergy, Lausanne University Hospital, University of Lausanne, 1011 Lausanne, Switzerland.
| | - Winfried Weissenhorn
- Institut de Biologie Structurale (IBS), University Grenoble Alpes, CEA, CNRS, 38000 Grenoble, France.
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14
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Structure of the membrane proximal external region of HIV-1 envelope glycoprotein. Proc Natl Acad Sci U S A 2018; 115:E8892-E8899. [PMID: 30185554 DOI: 10.1073/pnas.1807259115] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The membrane-proximal external region (MPER) of the HIV-1 envelope glycoprotein (Env) bears epitopes of broadly neutralizing antibodies (bnAbs) from infected individuals; it is thus a potential vaccine target. We report an NMR structure of the MPER and its adjacent transmembrane domain in bicelles that mimic a lipid-bilayer membrane. The MPER lies largely outside the lipid bilayer. It folds into a threefold cluster, stabilized mainly by conserved hydrophobic residues and potentially by interaction with phospholipid headgroups. Antigenic analysis and comparison with published images from electron cryotomography of HIV-1 Env on the virion surface suggest that the structure may represent a prefusion conformation of the MPER, distinct from the fusion-intermediate state targeted by several well-studied bnAbs. Very slow bnAb binding indicates that infrequent fluctuations of the MPER structure give these antibodies occasional access to alternative conformations of MPER epitopes. Mutations in the MPER not only impede membrane fusion but also influence presentation of bnAb epitopes in other regions. These results suggest strategies for developing MPER-based vaccine candidates.
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15
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Moyo T, Ereño-Orbea J, Jacob RA, Pavillet CE, Kariuki SM, Tangie EN, Julien JP, Dorfman JR. Molecular Basis of Unusually High Neutralization Resistance in Tier 3 HIV-1 Strain 253-11. J Virol 2018; 92:e02261-17. [PMID: 29618644 PMCID: PMC6026760 DOI: 10.1128/jvi.02261-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 02/26/2018] [Indexed: 01/06/2023] Open
Abstract
Understanding the mechanisms used by HIV-1 to evade antibody neutralization may contribute to the design of a high-coverage vaccine. The tier 3 virus 253-11 is poorly neutralized by subtype-matched and subtype C sera, even compared to other tier 3 viruses, and is also recognized poorly by V3/glycan-targeting monoclonal antibodies (MAbs). We found that sequence polymorphisms in the V3 loop and N-linked glycosylation sites contribute only minimally to the high neutralization resistance of 253-11. Interestingly, the 253-11 membrane-proximal external region (MPER) is rarely recognized by sera in the context of the wild-type virus but is commonly recognized in the context of an HIV-2 chimera, suggesting steric or kinetic hindrance of binding to MPER in the native envelope (Env). Mutations in the 253-11 MPER, which were previously reported to increase the lifetime of the prefusion Env conformation, affected the resistance of 253-11 to antibodies targeting various epitopes on HIV-1 Env, presumably destabilizing its otherwise stable, closed trimer structure. To gain insight into the structure of 253-11, we constructed and crystallized a recombinant 253-11 SOSIP trimer. The resulting structure revealed that the heptad repeat helices in gp41 are drawn in close proximity to the trimer axis and that gp120 protomers also showed a relatively compact disposition around the trimer axis. These observations give substantial insight into the molecular features of an envelope spike from a tier 3 virus and into possible mechanisms that may contribute to its unusually high neutralization resistance.IMPORTANCE HIV-1 isolates that are highly resistant to broadly neutralizing antibodies could limit the efficacy of an antibody-based vaccine. We studied 253-11, which is highly resistant to commonly elicited neutralizing antibodies. To further understand its resistance, we made mutations that are known to delay fusion and thus increase the time that the virus spends in the open conformation following CD4 binding. Interestingly, we found that these mutations affect the 253-11 envelope (Env) spike before CD4 binding, presumably by destabilizing the trimer structure. To gain further information about the structure of the 253-11 Env trimer, we generated a recombinant 253-11 SOSIP trimer. The crystal structure of the SOSIP trimer revealed that the gp41 helices and the gp120 protomers were drawn in toward the center of the molecule compared to most solved HIV-1 Env structures. These observations provide insight into the distinct molecular features of a tier 3 envelope spike.
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Affiliation(s)
- Thandeka Moyo
- Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
| | - June Ereño-Orbea
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
| | - Rajesh Abraham Jacob
- Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
- International Centre for Genetic Engineering and Biotechnology, Cape Town, South Africa
| | - Clara E Pavillet
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
| | - Samuel Mundia Kariuki
- Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
- International Centre for Genetic Engineering and Biotechnology, Cape Town, South Africa
- Department of Biological Science, University of Eldoret, Eldoret, Kenya
| | - Emily N Tangie
- Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
- International Centre for Genetic Engineering and Biotechnology, Cape Town, South Africa
| | - Jean-Philippe Julien
- Program in Molecular Medicine, The Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
- Department of Biochemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Jeffrey R Dorfman
- Division of Immunology, Department of Pathology, University of Cape Town, Cape Town, South Africa
- Division of Immunology, School of Pathology, University of the Witwatersrand, Johannesburg, South Africa
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16
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Bowder D, Hollingsead H, Durst K, Hu D, Wei W, Wiggins J, Medjahed H, Finzi A, Sodroski J, Xiang SH. Contribution of the gp120 V3 loop to envelope glycoprotein trimer stability in primate immunodeficiency viruses. Virology 2018; 521:158-168. [PMID: 29936340 PMCID: PMC6053598 DOI: 10.1016/j.virol.2018.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 06/09/2018] [Accepted: 06/11/2018] [Indexed: 02/06/2023]
Abstract
The V3 loop of the human immunodeficiency virus type 1 (HIV-1) gp120 exterior envelope glycoprotein (Env) becomes exposed after CD4 binding and contacts the coreceptor to mediate viral entry. Prior to CD4 engagement, a hydrophobic patch located at the tip of the V3 loop stabilizes the non-covalent association of gp120 with the Env trimer of HIV-1 subtype B strains. Here, we show that this conserved hydrophobic patch (amino acid residues 307, 309 and 317) contributes to gp120-trimer association in HIV-1 subtype C, HIV-2 and SIV. Changes that reduced the hydrophobicity of these V3 residues resulted in increased gp120 shedding and decreased Env-mediated cell-cell fusion and virus entry in the different primate immunodeficiency viruses tested. Thus, the hydrophobic patch is an evolutionarily conserved element in the tip of the gp120 V3 loop that plays an essential role in maintaining the stability of the pre-triggered Env trimer in diverse primate immunodeficiency viruses. The V3-loop of HIV-1 gp120 contributes to Env trimer stability and viral entry. The hydrophobic patch in the tip of the V3 loop is critical for pre-triggered Env trimer stability. The hydrophobic patch is a conserved motif in primate immunodeficiency viruses.
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Affiliation(s)
- Dane Bowder
- Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583, United States; School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583, United States
| | - Haley Hollingsead
- Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583, United States; School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583, United States
| | - Kate Durst
- Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583, United States; School of Biological Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583, United States
| | - Duoyi Hu
- Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583, United States; School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583, United States
| | - Wenzhong Wei
- Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583, United States; School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583, United States
| | - Joshua Wiggins
- Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583, United States; School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583, United States
| | - Halima Medjahed
- Centre de Recherche du CHUM, Department of Microbiology, Infectious Diseases and Immunology, Université de Montréal, Montreal, QC, Canada
| | - Andrés Finzi
- Centre de Recherche du CHUM, Department of Microbiology, Infectious Diseases and Immunology, Université de Montréal, Montreal, QC, Canada
| | - Joseph Sodroski
- Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, United States; Department of Microbiology and Immunobiology, Division of AIDS, Harvard Medical School, Boston, MA 02215, United States; Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA 02115, United States
| | - Shi-Hua Xiang
- Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583, United States; School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, Lincoln, NE 68583, United States.
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17
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Functional Optimization of Broadly Neutralizing HIV-1 Antibody 10E8 by Promotion of Membrane Interactions. J Virol 2018; 92:JVI.02249-17. [PMID: 29386285 DOI: 10.1128/jvi.02249-17] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 01/26/2018] [Indexed: 11/20/2022] Open
Abstract
The 10E8 antibody targets a helical epitope in the membrane-proximal external region (MPER) and transmembrane domain (TMD) of the envelope glycoprotein (Env) subunit gp41 and is among the broadest known neutralizing antibodies against HIV-1. Accordingly, this antibody and its mechanism of action valuably inform the design of effective vaccines and immunotherapies. 10E8 exhibits unusual adaptations to attain specific, high-affinity binding to the MPER at the viral membrane interface. Reversing the charge of the basic paratope surface (from net positive to net negative) reportedly lowered its neutralization potency. Here, we hypothesized that by increasing the net positive charge in similar polar surface patches, the neutralization potency of the antibody may be enhanced. We found that an increased positive charge at this paratope surface strengthened an electrostatic interaction between the antibody and lipid bilayers, enabling 10E8 to interact spontaneously with membranes. Notably, the modified 10E8 antibody did not gain any apparent polyreactivity and neutralized virus with a significantly greater potency. Binding analyses indicated that the optimized 10E8 antibody bound with a higher affinity to the epitope peptide anchored in lipid bilayers and to Env spikes on virions. Overall, our data provide a proof of principle for the rational optimization of 10E8 via manipulation of its interaction with the membrane element of its epitope. However, the observation that a similar mutation strategy did not affect the potency of the first-generation anti-MPER antibody 4E10 shows possible limitations of this principle. Altogether, our results emphasize the crucial role played by the viral membrane in the antigenicity of the MPER-TMD of HIV-1.IMPORTANCE The broadly neutralizing antibody 10E8 blocks infection by nearly all HIV-1 isolates, a capacity which vaccine design seeks to reproduce. Engineered versions of this antibody also represent a promising treatment for HIV infection by passive immunization. Understanding its mechanism of action is therefore important to help in developing effective vaccines and biologics to combat HIV/AIDS. 10E8 engages its helical MPER epitope where the base of the envelope spike submerges into the viral membrane. To enable this interaction, this antibody evolved an unusual property: the ability to interact with the membrane surface. Here, we provide evidence that 10E8 can be made more effective by enhancing its interactions with membranes. Our findings strengthen the idea that to elicit antibodies similar to 10E8, vaccines must reproduce the membrane environment where these antibodies perform their function.
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18
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Nandagopal P, Bhattacharya J, Srikrishnan AK, Goyal R, Ravichandran Swathirajan C, Patil S, Saravanan S, Deshpande S, Vignesh R, Solomon SS, Singla N, Mukherjee J, Murugavel KG. Broad neutralization response in a subset of HIV-1 subtype C-infected viraemic non-progressors from southern India. J Gen Virol 2018; 99:379-392. [PMID: 29458681 DOI: 10.1099/jgv.0.001016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Broadly neutralizing antibodies (bnAbs) have been considered to be potent therapeutic tools and potential vaccine candidates to enable protection against various clades of human immunodeficiency virus (HIV). The generation of bnAbs has been associated with enhanced exposure to antigen, high viral load and low CD4+ T cell counts, among other factors. However, only limited data are available on the generation of bnAbs in viraemic non-progressors that demonstrate moderate to high viraemia. Further, since HIV-1 subtype C viruses account for more than 50 % of global HIV infections, the identification of bnAbs with novel specificities is crucial to enable the development of potent tools to aid in HIV therapy and prevention. In the present study, we analysed and compared the neutralization potential of responses in 70 plasma samples isolated from ART-naïve HIV-1 subtype C-infected individuals with various disease progression profiles against a panel of 30 pseudoviruses. Among the seven samples that exhibited a neutralization breadth of ≥70 %, four were identified as 'elite neutralizers', and three of these were from viraemic non-progressors while the fourth was from a typical progressor. Analysis of the neutralization specificities revealed that none of the four elite neutralizers were reactive to epitopes in the membrane proximal external region (MPER), CD4-binding site and V1V2 or V3 glycan. However, two of the four elite neutralizers exhibited enhanced sensitivity towards viruses lacking N332 glycan, indicating high neutralization potency. Overall, our findings indicate that the identification of potent neutralization responses with distinct epitope specificities is possible from the as yet unexplored Indian population, which has a high prevalence of HIV-1 subtype C infection.
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Affiliation(s)
| | - Jayanta Bhattacharya
- HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, Faridabad, India
| | | | - Rajat Goyal
- International AIDS Vaccine Initiative (IAVI), New Delhi, India
| | | | - Shilpa Patil
- HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, Faridabad, India
| | | | - Suprit Deshpande
- HIV Vaccine Translational Research Laboratory, Translational Health Science and Technology Institute, Faridabad, India
| | - Ramachandran Vignesh
- YRG Center for AIDS Research and Education, Chennai, India.,Laboratory-based Department, UniKL-Royal College of Medicine Perak (UniKL-RCMP), Universiti Kuala Lumpur, Greentown, Ipoh 30450, Malaysia
| | - Sunil Suhas Solomon
- YRG Center for AIDS Research and Education, Chennai, India.,Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Nikhil Singla
- International AIDS Vaccine Initiative (IAVI), New Delhi, India
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19
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Molinos-Albert LM, Clotet B, Blanco J, Carrillo J. Immunologic Insights on the Membrane Proximal External Region: A Major Human Immunodeficiency Virus Type-1 Vaccine Target. Front Immunol 2017; 8:1154. [PMID: 28970835 PMCID: PMC5609547 DOI: 10.3389/fimmu.2017.01154] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 08/31/2017] [Indexed: 12/12/2022] Open
Abstract
Broadly neutralizing antibodies (bNAbs) targeting conserved regions within the human immunodeficiency virus type-1 (HIV-1) envelope glycoprotein (Env) can be generated by the human immune system and their elicitation by vaccination will be a key point to protect against the wide range of viral diversity. The membrane proximal external region (MPER) is a highly conserved region within the Env gp41 subunit, plays a major role in membrane fusion and is targeted by naturally induced bNAbs. Therefore, the MPER is considered as an attractive vaccine target. However, despite many attempts to design MPER-based immunogens, further study is still needed to understand its structural complexity, its amphiphilic feature, and its limited accessibility by steric hindrance. These particular features compromise the development of MPER-specific neutralizing responses during natural infection and limit the number of bNAbs isolated against this region, as compared with other HIV-1 vulnerability sites, and represent additional hurdles for immunogen development. Nevertheless, the analysis of MPER humoral responses elicited during natural infection as well as the MPER bNAbs isolated to date highlight that the human immune system is capable of generating MPER protective antibodies. Here, we discuss the recent advances describing the immunologic and biochemical features that make the MPER a unique HIV-1 vulnerability site, the different strategies to generate MPER-neutralizing antibodies in immunization protocols and point the importance of extending our knowledge toward new MPER epitopes by the isolation of novel monoclonal antibodies. This will be crucial for the redesign of immunogens able to skip non-neutralizing MPER determinants.
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Affiliation(s)
- Luis M Molinos-Albert
- IrsiCaixa AIDS Research Institute, Institut de Recerca Germans Trias i Pujol (IGTP), Germans Trias i Pujol University Hospital, Barcelona, Spain
| | - Bonaventura Clotet
- IrsiCaixa AIDS Research Institute, Institut de Recerca Germans Trias i Pujol (IGTP), Germans Trias i Pujol University Hospital, Barcelona, Spain.,Universitat de Vic - Universitat Central de Catalunya, Barcelona, Spain
| | - Julià Blanco
- IrsiCaixa AIDS Research Institute, Institut de Recerca Germans Trias i Pujol (IGTP), Germans Trias i Pujol University Hospital, Barcelona, Spain.,Universitat de Vic - Universitat Central de Catalunya, Barcelona, Spain
| | - Jorge Carrillo
- IrsiCaixa AIDS Research Institute, Institut de Recerca Germans Trias i Pujol (IGTP), Germans Trias i Pujol University Hospital, Barcelona, Spain
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20
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Cerutti N, Loredo-Varela JL, Caillat C, Weissenhorn W. Antigp41 membrane proximal external region antibodies and the art of using the membrane for neutralization. Curr Opin HIV AIDS 2017; 12:250-256. [PMID: 28422789 DOI: 10.1097/coh.0000000000000364] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PURPOSE OF REVIEW We summarize the latest research on the progress to understand the neutralizing epitopes present within the membrane proximal external region (MPER) of the HIV-1 fusion protein subunit gp41. RECENT FINDINGS The HIV-1 fusion protein subunit gp41 contains a highly conserved sequence that is essential for membrane fusion and targeted by broadly neutralizing antibodies such as 2F5, 4E10, Z13e1, and 10E8. These antibodies recognize a linear gp41 epitope with high affinity, but require additional hydrophobic sequences present in their heavy chain CDR3 for neutralization. Recent structural studies on mAbs 4E10 and 10E8 provide molecular details for specific interactions with lipids and implicate part of the transmembrane region as the relevant 10E8 epitope. Although many different approaches have been applied to engineer gp41 immunogens that can induce broadly neutralizing antibodies directed toward MPER, only modest success has yet been reported. SUMMARY The new structural details on the complex gp41-lipidic epitope will spur new approaches to design gp41-MPER immunogens that might induce broadly neutralizing antibody responses.
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Affiliation(s)
- Nichole Cerutti
- aUniversity Grenoble Alpes bCEA cCNRS, Institut de Biologie Structurale (IBS), Grenoble, France
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21
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Meador LR, Kessans SA, Kilbourne J, Kibler KV, Pantaleo G, Roderiguez ME, Blattman JN, Jacobs BL, Mor TS. A heterologous prime-boosting strategy with replicating Vaccinia virus vectors and plant-produced HIV-1 Gag/dgp41 virus-like particles. Virology 2017; 507:242-256. [PMID: 28458036 PMCID: PMC5529300 DOI: 10.1016/j.virol.2017.04.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 03/24/2017] [Accepted: 04/06/2017] [Indexed: 12/22/2022]
Abstract
Showing modest efficacy, the RV144 HIV-1 vaccine clinical trial utilized a non-replicating canarypox viral vector and a soluble gp120 protein boost. Here we built upon the RV144 strategy by developing a novel combination of a replicating, but highly-attenuated Vaccinia virus vector, NYVAC-KC, and plant-produced HIV-1 virus-like particles (VLPs). Both components contained the full-length Gag and a membrane anchored truncated gp41 presenting the membrane proximal external region with its conserved broadly neutralizing epitopes in the pre-fusion conformation. We tested different prime/boost combinations of these components in mice and showed that the group primed with NYVAC-KC and boosted with both the viral vectors and plant-produced VLPs have the most robust Gag-specific CD8 T cell responses, at 12.7% of CD8 T cells expressing IFN-γ in response to stimulation with five Gag epitopes. The same immunization group elicited the best systemic and mucosal antibody responses to Gag and dgp41 with a bias towards IgG1.
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Affiliation(s)
- Lydia R Meador
- Ira A. Fulton School of Engineering, Arizona State University, Tempe, AZ, USA; Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Sarah A Kessans
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, USA; School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Jacquelyn Kilbourne
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Karen V Kibler
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, USA
| | - Giuseppe Pantaleo
- Division of Immunology and Allergy, Centre Hospitalier Universitaire Vaudois, University of Lausanne, Lausanne, Switzerland; Swiss Vaccine Research Institute, Lausanne, Switzerland
| | | | - Joseph N Blattman
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, USA; School of Life Sciences, Arizona State University, Tempe, AZ, USA
| | - Bertram L Jacobs
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, USA; School of Life Sciences, Arizona State University, Tempe, AZ, USA.
| | - Tsafrir S Mor
- Center for Infectious Diseases and Vaccinology, The Biodesign Institute, Arizona State University, Tempe, AZ, USA; School of Life Sciences, Arizona State University, Tempe, AZ, USA.
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22
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Differential Antibody Responses to Conserved HIV-1 Neutralizing Epitopes in the Context of Multivalent Scaffolds and Native-Like gp140 Trimers. mBio 2017; 8:mBio.00036-17. [PMID: 28246356 PMCID: PMC5347340 DOI: 10.1128/mbio.00036-17] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Broadly neutralizing antibodies (bNAbs) have provided valuable insights into the humoral immune response to HIV-1. While rationally designed epitope scaffolds and well-folded gp140 trimers have been proposed as vaccine antigens, a comparative understanding of their antibody responses has not yet been established. In this study, we probed antibody responses to the N332 supersite and the membrane-proximal external region (MPER) in the context of heterologous protein scaffolds and native-like gp140 trimers. Ferritin nanoparticles and fragment crystallizable (Fc) regions were utilized as multivalent carriers to display scaffold antigens with grafted N332 and MPER epitopes, respectively. Trimeric scaffolds were also identified to stabilize the MPER-containing BG505 gp140.681 trimer in a native-like conformation. Following structural and antigenic evaluation, a subset of scaffold and trimer antigens was selected for immunization in BALB/c mice. Serum binding revealed distinct patterns of antibody responses to these two bNAb targets presented in different structural contexts. For example, the N332 nanoparticles elicited glycan epitope-specific antibody responses that could also recognize the native trimer, while a scaffolded BG505 gp140.681 trimer generated a stronger and more rapid antibody response to the trimer apex than its parent gp140.664 trimer. Furthermore, next-generation sequencing (NGS) of mouse splenic B cells revealed expansion of antibody lineages with long heavy-chain complementarity-determining region 3 (HCDR3) loops upon activation by MPER scaffolds, in contrast to the steady repertoires primed by N332 nanoparticles and a soluble gp140.664 trimer. These findings will facilitate the future development of a coherent vaccination strategy that combines both epitope-focused and trimer-based approaches.IMPORTANCE Both epitope-focused and trimer-based strategies are currently being explored in HIV-1 vaccine development, which aims to elicit broadly neutralizing antibodies (bNAbs) targeting conserved epitopes on the viral envelope (Env). However, little is known about the differences in antibody response to these bNAb targets presented by foreign scaffolds and native Env. In this study, a systematic effort was undertaken to design multivalent epitope scaffolds and soluble gp140.681 trimers with a complete antigenic surface, and to comparatively analyze the antibody responses elicited by these antigens to the N332 supersite and MPER in a mouse model. This study will inform both epitope-focused and trimer-based vaccine design and will facilitate integration of the two vaccine strategies.
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23
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Rujas E, Caaveiro JMM, Insausti S, García-Porras M, Tsumoto K, Nieva JL. Peripheral Membrane Interactions Boost the Engagement by an Anti-HIV-1 Broadly Neutralizing Antibody. J Biol Chem 2017; 292:5571-5583. [PMID: 28213514 DOI: 10.1074/jbc.m117.775429] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 02/16/2017] [Indexed: 12/16/2022] Open
Abstract
The 4E10 antibody displays an extreme breadth of HIV-1 neutralization and therefore constitutes a suitable model system for structure-guided vaccine design and immunotherapeutics against AIDS. In this regard, the relevance of autoreactivity with membrane lipids for the biological function of this antibody is still a subject of controversy. To address this dispute, herein we have compared the membrane partitioning ability of the 4E10 antibody and several of its variants, which were mutated at the region of the paratope surface in contact with the membrane interface. We first employed a physical separation approach (vesicle flotation) and subsequently carried out quantitative fluorescence measurements in an intact system (spectroscopic titration), using 4E10 Fab labeled with a polarity-sensitive fluorescent probe. Moreover, recognition of epitope peptide in membrane was demonstrated by photo-cross-linking assays using a Fab that incorporated the genetically encoded unnatural amino acid p-benzoylphenylalanine. The experimental data ruled out that the proposed stereospecific recognition of viral lipids was necessary for the function of the antibody. In contrast, our data suggest that nonspecific electrostatic interactions between basic residues of 4E10 and acidic phospholipids in the membranes contribute to the observed biological function. Moreover, the energetics of membrane partitioning indicated that 4E10 behaves as a peripheral membrane protein, tightening the binding to the ligand epitope inserted in the viral membrane. The implications of these findings for the natural production and biological function of this antibody are discussed.
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Affiliation(s)
- Edurne Rujas
- From the Biofisika Institute (Consejo Superior de Investigaciones Científicas, UPV/EHU), and Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain and.,the Department of Bioengineering, Graduate School of Engineering, University of Tokyo, Tokyo, 113-8656, Japan
| | - José M M Caaveiro
- the Department of Bioengineering, Graduate School of Engineering, University of Tokyo, Tokyo, 113-8656, Japan
| | - Sara Insausti
- From the Biofisika Institute (Consejo Superior de Investigaciones Científicas, UPV/EHU), and Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain and
| | - Miguel García-Porras
- From the Biofisika Institute (Consejo Superior de Investigaciones Científicas, UPV/EHU), and Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain and
| | - Kouhei Tsumoto
- the Department of Bioengineering, Graduate School of Engineering, University of Tokyo, Tokyo, 113-8656, Japan
| | - José L Nieva
- From the Biofisika Institute (Consejo Superior de Investigaciones Científicas, UPV/EHU), and Department of Biochemistry and Molecular Biology, University of the Basque Country (UPV/EHU), 48080 Bilbao, Spain and
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24
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Witt KC, Castillo-Menendez L, Ding H, Espy N, Zhang S, Kappes JC, Sodroski J. Antigenic characterization of the human immunodeficiency virus (HIV-1) envelope glycoprotein precursor incorporated into nanodiscs. PLoS One 2017; 12:e0170672. [PMID: 28151945 PMCID: PMC5289478 DOI: 10.1371/journal.pone.0170672] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 01/09/2017] [Indexed: 01/13/2023] Open
Abstract
The entry of human immunodeficiency virus (HIV-1) into host cells is mediated by the viral envelope glycoproteins (Envs), which are derived by the proteolytic cleavage of a trimeric gp160 Env precursor. The mature Env trimer is a major target for entry inhibitors and vaccine-induced neutralizing antibodies. Env interstrain variability, conformational flexibility and heavy glycosylation contribute to evasion of the host immune response, and create challenges for structural characterization and vaccine development. Here we investigate variables associated with reconstitution of the HIV-1 Env precursor into nanodiscs, nanoscale lipid bilayer discs enclosed by membrane scaffolding proteins. We identified detergents, as well as lipids similar in composition to the viral lipidome, that allowed efficient formation of Env-nanodiscs (Env-NDs). Env-NDs were created with the full-length Env precursor and with an Env precursor with the majority of the cytoplasmic tail intact. The self-association of Env-NDs was decreased by glutaraldehyde crosslinking. The Env-NDs exhibited an antigenic profile expected for the HIV-1 Env precursor. Env-NDs were recognized by broadly neutralizing antibodies. Of note, neutralizing antibody epitopes in the gp41 membrane-proximal external region and in the gp120:gp41 interface were well exposed on Env-NDs compared with Env expressed on cell surfaces. Most Env epitopes recognized by non-neutralizing antibodies were masked on the Env-NDs. This antigenic profile was stable for several days, exhibiting a considerably longer half-life than that of Env solubilized in detergents. Negative selection with weak neutralizing antibodies could be used to improve the antigenic profile of the Env-NDs. Finally, we show that lipid adjuvants can be incorporated into Env-NDs. These results indicate that Env-NDs represent a potentially useful platform for investigating the structural, functional and antigenic properties of the HIV-1 Env trimer in a membrane context.
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Affiliation(s)
- Kristen C. Witt
- Department of Cancer Immunology & Virology, Dana-Farber Cancer Institute, Department of Microbiology & Immunobiology, Harvard Medical School, Boston, MA, United States of America
| | - Luis Castillo-Menendez
- Department of Cancer Immunology & Virology, Dana-Farber Cancer Institute, Department of Microbiology & Immunobiology, Harvard Medical School, Boston, MA, United States of America
| | - Haitao Ding
- Departments of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States of America
| | - Nicole Espy
- Department of Cancer Immunology & Virology, Dana-Farber Cancer Institute, Department of Microbiology & Immunobiology, Harvard Medical School, Boston, MA, United States of America
| | - Shijian Zhang
- Department of Cancer Immunology & Virology, Dana-Farber Cancer Institute, Department of Microbiology & Immunobiology, Harvard Medical School, Boston, MA, United States of America
| | - John C. Kappes
- Departments of Medicine, University of Alabama at Birmingham, Birmingham, AL, United States of America
- Birmingham Veterans Affairs Medical Center, Research Service, Birmingham, AL, United States of America
| | - Joseph Sodroski
- Department of Cancer Immunology & Virology, Dana-Farber Cancer Institute, Department of Microbiology & Immunobiology, Harvard Medical School, Boston, MA, United States of America
- Department of Immunology & Infectious Diseases, Harvard School of Public Health, Boston, MA, United States of America
- * E-mail:
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25
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Chinks in the armor of the HIV-1 Envelope glycan shield: Implications for immune escape from anti-glycan broadly neutralizing antibodies. Virology 2016; 501:12-24. [PMID: 27846415 DOI: 10.1016/j.virol.2016.10.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Accepted: 10/28/2016] [Indexed: 11/22/2022]
Abstract
Glycans on HIV-1 Envelope serve multiple functions including blocking epitopes from antibodies. We show that removal of glycan 301, a major target of anti-V3/glycan antibodies, has substantially different effects in two viruses. While glycan 301 on Du156.12 blocks epitopes commonly recognized by sera from chronically HIV-1-infected individuals, it does not do so on CAP45.G3, suggesting that removing the 301 glycan has a smaller effect on the integrity of the glycan shield in CAP45.G3. Changes in sensitivity to broadly neutralizing monoclonal antibodies suggest that the interaction between glycan 301 and the CD4 binding site differ substantially between these 2 viruses. Molecular modeling suggests that removal of glycan 301 likely exposes a greater surface area of the V3 and C4 regions in Du156.12. Our data indicate that the contribution of the 301 glycan to resistance to common neutralizing antibodies varies between viruses, allowing for easier selection for its loss in some viruses.
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26
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Generation of Long-Lived Bone Marrow Plasma Cells Secreting Antibodies Specific for the HIV-1 gp41 Membrane-Proximal External Region in the Absence of Polyreactivity. J Virol 2016; 90:8875-90. [PMID: 27466419 PMCID: PMC5021391 DOI: 10.1128/jvi.01089-16] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 07/18/2016] [Indexed: 12/28/2022] Open
Abstract
UNLABELLED An effective preventive vaccine is highly sought after in order to stem the current HIV-1 pandemic. Both conservation of contiguous gp41 membrane-proximal external region (MPER) amino acid sequences across HIV-1 clades and the ability of anti-MPER broadly neutralizing antibodies (BNAbs) to block viral hemifusion/fusion establish the MPER as a prime vaccination target. In earlier studies, we described the development of an MPER vaccine formulation that takes advantage of liposomes to array the MPER on a lipid bilayer surface, paralleling its native configuration on the virus membrane while also incorporating molecular adjuvant and CD4 T cell epitope cargo. Here we demonstrate that several immunizations with MPER/liposomes induce high levels of bone marrow long-lived plasma cell (LLPC) antibody production. Single-cell immunoglobulin gene retrieval analysis shows that these plasma cells are derived from a germ line repertoire of B cells with a diverse representation of immunoglobulin genes, exhibiting antigen-driven positive selection. Characterization of LLPC recombinant monoclonal antibodies (rMAbs) indicates that antigen recognition is achieved through convergence on a common epitopic focus by utilizing various complementarity-determining region H3 (CDRH3) lengths. Importantly, the vast majority of rMAbs produced from these cells lack polyreactivity yet manifest antigen specificity in the context of lipids, shaping MPER-specific paratopes through selective pressure. Taken together, these findings demonstrate that the MPER is a vaccine target with minimal risk of generating off-target autoimmunity. IMPORTANCE A useful vaccine must generate desired long-term, antigen-specific antibody responses devoid of polyreactivity or autoreactivity. The common polyreactive features of some HIV-1 BNAbs have raised concern about elicitation of anti-MPER antibodies. Utilizing single-LLPC repertoire analysis and biophysical characterization of anti-MPER rMAbs, we show that their fine specificities require a structural fitness of the antibody combining site involving heavy and light chain variable domains shaped by somatic hypermutation and affinity maturation of B cells in the germinal center. Perhaps more importantly, our results demonstrate that the majority of MPER-specific antibodies are not inherently polyspecific and/or autoreactive, suggesting that polyreactivity of MPER-specific antibodies is separable from their antigen specificity.
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27
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Bolhassani A, Kardani K, Vahabpour R, Habibzadeh N, Aghasadeghi MR, Sadat SM, Agi E. Prime/boost immunization with HIV-1 MPER-V3 fusion construct enhances humoral and cellular immune responses. Immunol Lett 2015; 168:366-73. [PMID: 26518142 DOI: 10.1016/j.imlet.2015.10.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 10/17/2015] [Accepted: 10/20/2015] [Indexed: 01/15/2023]
Abstract
Development of an effective vaccine against HIV-1 infection is a main concern in worldwide. A potent vaccine for HIV-1 requires the induction and maintenance of both humoral and cellular immunity. In this study, the levels of humoral and cellular immune responses were compared using MPER-V3 injection in three immunization strategies such as DNA/DNA, peptide/peptide, and DNA/peptide (prime-boost). MPG peptide and Montanide 720 were used as a DNA delivery system, and as a peptide adjuvant, respectively. Our results demonstrated that MPG forms stable non-covalent nanoparticles with plasmid DNA at N/P ratio of 10:1 (∼ 110-130 nm). The in vitro transfection efficiency of MPER-V3 DNA using MPG was comparable with lipofectamine and turbofect reagents as a common delivery system. In vivo prime-boost immunization using HIV-1 MPER-V3 could significantly enhance humoral and cellular immune responses as compared to control groups. The mixture of IgG1 and IgG2a was observed for each strategy, but IFN-γ production was significantly higher in prime-boost and peptide immunizations than that in DNA immunizations, inducing Th1 response. Moreover, our data showed that prime immunization with low dose of the nanoparticles (MPER-V3 DNA: MPG at ratio of 1:10) followed by MPER-V3 peptide drives T cell responses towards a Th1-type similar to high dose of the naked DNA prime/peptide boost immunization. Generally, the prime-boost strategy could improve both immune responses against MPER and especially V3 peptides suggesting its application as a promising HIV vaccine candidate in future.
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Affiliation(s)
- Azam Bolhassani
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran.
| | - Kimia Kardani
- Department of Biotechnology, Faculty of Advanced Sciences and Technology, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran, Iran
| | | | - Nourieh Habibzadeh
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
| | | | - Seyed Mehdi Sadat
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
| | - Elnaz Agi
- Department of Hepatitis and AIDS, Pasteur Institute of Iran, Tehran, Iran
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