201
|
Verkoczy L, Kelsoe G, Haynes BF. HIV-1 envelope gp41 broadly neutralizing antibodies: hurdles for vaccine development. PLoS Pathog 2014; 10:e1004073. [PMID: 24853821 PMCID: PMC4031215 DOI: 10.1371/journal.ppat.1004073] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Affiliation(s)
- Laurent Verkoczy
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Pathology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Garnett Kelsoe
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Immunology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Barton F. Haynes
- Duke Human Vaccine Institute, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Department of Immunology, Duke University School of Medicine, Durham, North Carolina, United States of America
- * E-mail:
| |
Collapse
|
202
|
Saez-Cirion A, Jacquelin B, Barré-Sinoussi F, Müller-Trutwin M. Immune responses during spontaneous control of HIV and AIDS: what is the hope for a cure? Philos Trans R Soc Lond B Biol Sci 2014; 369:20130436. [PMID: 24821922 PMCID: PMC4024229 DOI: 10.1098/rstb.2013.0436] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
HIV research has made rapid progress and led to remarkable achievements in recent decades, the most important of which are combination antiretroviral therapies (cART). However, in the absence of a vaccine, the pandemic continues, and additional strategies are needed. The 'towards an HIV cure' initiative aims to eradicate HIV or at least bring about a lasting remission of infection during which the host can control viral replication in the absence of cART. Cases of spontaneous and treatment-induced control of infection offer substantial hope. Here, we describe the scientific knowledge that is lacking, and the priorities that have been established for research into a cure. We discuss in detail the immunological lessons that can be learned by studying natural human and animal models of protection and spontaneous control of viraemia or of disease progression. In particular, we describe the insights we have gained into the immune mechanisms of virus control, the impact of early virus-host interactions and why chronic inflammation, a hallmark of HIV infection, is an obstacle to a cure. Finally, we enumerate current interventions aimed towards improving the host immune response.
Collapse
Affiliation(s)
| | | | | | - M. Müller-Trutwin
- Institut Pasteur, Unité de Régulation des Infections Rétrovirales, Paris, France
| |
Collapse
|
203
|
Derdeyn CA, Moore PL, Morris L. Development of broadly neutralizing antibodies from autologous neutralizing antibody responses in HIV infection. Curr Opin HIV AIDS 2014; 9:210-6. [PMID: 24662931 PMCID: PMC4068799 DOI: 10.1097/coh.0000000000000057] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
PURPOSE OF REVIEW Detailed genetic and structural characterization has revealed that broadly neutralizing antibodies (bnAbs) against HIV-1 have unusually high levels of somatic hypermutation, long CDRH3 domains, and the ability to target one of four sites of vulnerability on the HIV-1 envelope (Env) glycoproteins. A current priority is to understand how bnAbs are generated during natural infection, and translate this information into immunogens that can elicit bnAb following vaccination. RECENT FINDINGS Strain-specific neutralizing antibodies can acquire broad neutralizing capacity when the transmitted/founder Env or a specific Env variant is recognized by an unmutated rearranged germline that has the capacity to develop bnAb-like features. This event could be relatively infrequent, as only certain germlines appear to possess inherent features needed for bnAb activity. Furthermore, the glycosylation pattern and diversity of circulating HIV-1 Envs, as well as the state of the B-cell compartment, may influence the activation and maturation of certain antibody lineages. SUMMARY Collectively, studies over the last year have suggested that the development of HIV-1 Env immunogens that bind and activate bnAb-like germlines is feasible. However, more information about the features of Env variants and the host factors that lead to breadth during natural infection are needed to elicit bnAbs through immunization.
Collapse
Affiliation(s)
- Cynthia A. Derdeyn
- Emory Vaccine Center at Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, USA
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, USA
| | - Penny L. Moore
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Services, Johannesburg, South Africa
- University of the Witwatersrand, Johannesburg, South Africa
- Center for the AIDS Program of Research, Durban, South Africa
| | - Lynn Morris
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Services, Johannesburg, South Africa
- University of the Witwatersrand, Johannesburg, South Africa
- Center for the AIDS Program of Research, Durban, South Africa
| |
Collapse
|
204
|
Cohen YZ, Dolin R. Novel HIV vaccine strategies: overview and perspective. THERAPEUTIC ADVANCES IN VACCINES 2014; 1:99-112. [PMID: 24757518 DOI: 10.1177/2051013613494535] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A human immunodeficiency virus (HIV) vaccine remains a central component in the quest to control the worldwide epidemic. To examine the status of the development of HIV vaccines, we review the results of the efficacy trials carried out to date and the immunologic principles that guided them. Four vaccine concepts have been evaluated in HIV-1 vaccine efficacy trials, and the results of these trials have provided significant information for future vaccine development. While one of these trials demonstrated that a safe and effective HIV vaccine is possible, many questions remain regarding the basis for the observed protection and the most efficient way to stimulate it. Novel HIV vaccine strategies including induction of highly potent broadly neutralizing antibodies, use of novel homologous and heterologous vector systems, and vectored immunoprophylaxis seek to expand and build upon the knowledge gained from these trials.
Collapse
Affiliation(s)
- Yehuda Z Cohen
- Center for Virus and Vaccine Research, Beth Israel Deaconess Medical Center, E/CLS-1003, 330 Brookline Ave, Boston, 02215, USA
| | - Raphael Dolin
- Beth Israel Deaconess Medical Center, Boston, MA, USA
| |
Collapse
|
205
|
West AP, Scharf L, Scheid JF, Klein F, Bjorkman PJ, Nussenzweig MC. Structural insights on the role of antibodies in HIV-1 vaccine and therapy. Cell 2014; 156:633-48. [PMID: 24529371 DOI: 10.1016/j.cell.2014.01.052] [Citation(s) in RCA: 267] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Indexed: 11/30/2022]
Abstract
Despite 30 years of effort, there is no effective vaccine for HIV-1. However, antibodies can prevent HIV-1 infection in humanized mice and macaques when passively transferred. New single-cell-based methods have uncovered many broad and potent donor-derived antibodies, and structural studies have revealed the molecular bases for their activities. The new data suggest why such antibodies are difficult to elicit and inform HIV-1 vaccine development efforts. In addition to protecting against infection, the newly identified antibodies can suppress active infections in mice and macaques, suggesting they could be valuable additions to anti-HIV-1 therapies and to strategies to eradicate HIV-1 infection.
Collapse
Affiliation(s)
- Anthony P West
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA.
| | - Louise Scharf
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Johannes F Scheid
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Florian Klein
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA
| | - Pamela J Bjorkman
- Division of Biology and Biological Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA; Howard Hughes Medical Institute, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA
| | - Michel C Nussenzweig
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA; Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA.
| |
Collapse
|
206
|
Enhanced immunogenicity of an HIV-1 DNA vaccine delivered with electroporation via combined intramuscular and intradermal routes. J Virol 2014; 88:6959-69. [PMID: 24719412 DOI: 10.1128/jvi.00183-14] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
UNLABELLED It is accepted that an effective prophylactic HIV-1 vaccine is likely to have the greatest impact on viral transmission rates. As previous reports have implicated DNA-priming, protein boost regimens to be efficient activators of humoral responses, we sought to optimize this regimen to further augment vaccine immunogenicity. Here we evaluated single versus concurrent intradermal (i.d.) and intramuscular (i.m.) vaccinations as a DNA-priming strategy for their abilities to elicit humoral and cellular responses against a model HIV-1 vaccine antigen, CN54-gp140. To further augment vaccine-elicited T and B cell responses, we enhanced cellular transfection with electroporation and then boosted the DNA-primed responses with homologous protein delivered subcutaneously (s.c.), intranasally (i.n.), i.m., or transcutaneously (t.c.). In mice, the concurrent priming regimen resulted in significantly elevated gamma interferon T cell responses and high-avidity antigen-specific IgG B cell responses, a hallmark of B cell maturation. Protein boosting of the concurrent DNA strategy further enhanced IgG concentrations but had little impact on T cell reactivity. Interestingly protein boosting by the subcutaneous route increased antibody avidity to a greater extent than protein boosting by either the i.m., i.n., or t.c. route, suggesting that this route may be preferential for driving B cell maturation. Using an alternative and larger animal model, the rabbit, we found the concurrent DNA-priming strategy followed by s.c. protein boosting to again be capable of eliciting high-avidity humoral responses and to also be able to neutralize HIV-1 pseudoviruses from diverse clades (clades A, B, and C). Taken together, we show that concurrent multiple-route DNA vaccinations induce strong cellular immunity, in addition to potent and high-avidity humoral immune responses. IMPORTANCE The route of vaccination has profound effects on prevailing immune responses. Due to the insufficient immunogenicity and protection of current DNA delivery strategies, we evaluated concurrent DNA delivery via simultaneous administration of plasmid DNA by the i.m. and i.d. routes. The rationale behind this study was to provide clear evidence of the utility of concurrent vaccinations for an upcoming human clinical trial. Furthermore, this work will guide future preclinical studies by evaluating the use of model antigens and plasmids for prime-boost strategies. This paper will be of interest not only to virologists and vaccinologists working in the HIV field but also to researchers working in other viral vaccine settings and, critically, to the wider field of vaccine delivery.
Collapse
|
207
|
Excler JL, Robb ML, Kim JH. HIV-1 vaccines: challenges and new perspectives. Hum Vaccin Immunother 2014; 10:1734-46. [PMID: 24637946 DOI: 10.4161/hv.28462] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The development of a safe and effective preventive HIV-1 vaccine remains a public health priority. Despite scientific difficulties and disappointing results, HIV-1 vaccine clinical development has, for the first time, established proof-of-concept efficacy against HIV-1 acquisition and identified vaccine-associated immune correlates of risk. The correlate of risk analysis showed that IgG antibodies against the gp120 V2 loop correlated with decreased risk of HIV infection, while Env-specific IgA directly correlated with increased risk. The development of vaccine strategies such as improved envelope proteins formulated with potent adjuvants and DNA and vectors expressing mosaics, or conserved sequences, capable of eliciting greater breadth and depth of potentially relevant immune responses including neutralizing and non-neutralizing antibodies, CD4+ and CD8+ cell-mediated immune responses, mucosal immune responses, and immunological memory, is now proceeding quickly. Additional human efficacy trials combined with other prevention modalities along with sustained funding and international collaboration remain key to bring an HIV-1 vaccine to licensure.
Collapse
Affiliation(s)
- Jean-Louis Excler
- U.S. Military HIV Research Program; Division of Retrovirology; Walter Reed Army Institute of Research; Bethesda, MD USA; Henry M. Jackson Foundation for the Advancement of Military Medicine; Bethesda, MD USA
| | - Merlin L Robb
- U.S. Military HIV Research Program; Division of Retrovirology; Walter Reed Army Institute of Research; Bethesda, MD USA; Henry M. Jackson Foundation for the Advancement of Military Medicine; Bethesda, MD USA
| | - Jerome H Kim
- U.S. Military HIV Research Program; Division of Retrovirology; Walter Reed Army Institute of Research; Bethesda, MD USA
| |
Collapse
|
208
|
Molecular dynamics simulation of the crystallizable fragment of IgG1-insights for the design of Fcabs. Int J Mol Sci 2014; 15:438-55. [PMID: 24451126 PMCID: PMC3907818 DOI: 10.3390/ijms15010438] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2013] [Revised: 12/19/2013] [Accepted: 12/27/2013] [Indexed: 11/17/2022] Open
Abstract
An interesting format in the development of therapeutic monoclonal antibodies uses the crystallizable fragment of IgG1 as starting scaffold. Engineering of its structural loops allows generation of an antigen binding site. However, this might impair the molecule’s conformational stability, which can be overcome by introducing stabilizing point mutations in the CH3 domains. These point mutations often affect the stability and unfolding behavior of both the CH2 and CH3 domains. In order to understand this cross-talk, molecular dynamics simulations of the domains of the Fc fragment of human IgG1 are reported. The structure of human IgG1-Fc obtained from X-ray crystallography is used as a starting point for simulations of the wild-type protein at two different pH values. The stabilizing effect of a single point mutation in the CH3 domain as well as the impact of the hinge region and the glycan tree structure connected to the CH2 domains is investigated. Regions of high local flexibility were identified as potential sites for engineering antigen binding sites. Obtained data are discussed with respect to the available X-ray structure of IgG1-Fc, directed evolution approaches that screen for stability and use of the scaffold IgG1-Fc in the design of antigen binding Fc proteins.
Collapse
|
209
|
Dutta S, Dlugosz LS, Drew DR, Ge X, Ababacar D, Rovira YI, Moch JK, Shi M, Long CA, Foley M, Beeson JG, Anders RF, Miura K, Haynes JD, Batchelor AH. Overcoming antigenic diversity by enhancing the immunogenicity of conserved epitopes on the malaria vaccine candidate apical membrane antigen-1. PLoS Pathog 2013; 9:e1003840. [PMID: 24385910 PMCID: PMC3873463 DOI: 10.1371/journal.ppat.1003840] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 11/04/2013] [Indexed: 12/16/2022] Open
Abstract
Malaria vaccine candidate Apical Membrane Antigen-1 (AMA1) induces protection, but only against parasite strains that are closely related to the vaccine. Overcoming the AMA1 diversity problem will require an understanding of the structural basis of cross-strain invasion inhibition. A vaccine containing four diverse allelic proteins 3D7, FVO, HB3 and W2mef (AMA1 Quadvax or QV) elicited polyclonal rabbit antibodies that similarly inhibited the invasion of four vaccine and 22 non-vaccine strains of P. falciparum. Comparing polyclonal anti-QV with antibodies against a strain-specific, monovalent, 3D7 AMA1 vaccine revealed that QV induced higher levels of broadly inhibitory antibodies which were associated with increased conserved face and domain-3 responses and reduced domain-2 response. Inhibitory monoclonal antibodies (mAb) raised against the QV reacted with a novel cross-reactive epitope at the rim of the hydrophobic trough on domain-1; this epitope mapped to the conserved face of AMA1 and it encompassed the 1e-loop. MAbs binding to the 1e-loop region (1B10, 4E8 and 4E11) were ∼10-fold more potent than previously characterized AMA1-inhibitory mAbs and a mode of action of these 1e-loop mAbs was the inhibition of AMA1 binding to its ligand RON2. Unlike the epitope of a previously characterized 3D7-specific mAb, 1F9, the 1e-loop inhibitory epitope was partially conserved across strains. Another novel mAb, 1E10, which bound to domain-3, was broadly inhibitory and it blocked the proteolytic processing of AMA1. By itself mAb 1E10 was weakly inhibitory but it synergized with a previously characterized, strain-transcending mAb, 4G2, which binds close to the hydrophobic trough on the conserved face and inhibits RON2 binding to AMA1. Novel inhibition susceptible regions and epitopes, identified here, can form the basis for improving the antigenic breadth and inhibitory response of AMA1 vaccines. Vaccination with a few diverse antigenic proteins could provide universal coverage by redirecting the immune response towards conserved epitopes. Numerous reports of vaccine failure are attributed to a mismatch between the genotype of the vaccine and the circulating target strains. This observation is congruent to the view that polyvalent vaccines protect broadly by inducing a multitude of type-specific antibodies. Polyvalent vaccines that can overcome antigenic diversity by refocusing antibody responses towards conserved functional epitopes are highly desirable. Development of an Apical Membrane Antigen-1 (AMA1) malaria vaccine has been impeded by extreme antigenic diversity in the field. We present here a solution to the AMA1 diversity problem. Antibodies against a mixture of only four naturally occurring AMA1 allelic proteins “Quadvax” inhibited invasion of red blood cells by a diverse panel of malaria parasites that represented the global diversity of AMA1 in the field. Competition experiments suggested that in addition to improving the diversity of strain-specific antibodies, the mechanism of broadened inhibition involved an increase in responses against conserved inhibitory epitopes. Monoclonal antibodies against the Quadvax inhibited invasion either by blocking the binding of AMA1 to its receptor RON2 or by blocking a crucial proteolytic processing event. Some mixtures of these antibodies were much more effective than expected and were shown to act synergistically. Together these two classes of functional invasion inhibitory epitopes can be targeted to engineer a more potent AMA1 vaccine.
Collapse
MESH Headings
- Amino Acid Sequence
- Animals
- Antibodies, Monoclonal/chemistry
- Antibodies, Monoclonal/immunology
- Antigenic Variation/genetics
- Antigenic Variation/immunology
- Antigens, Protozoan/chemistry
- Antigens, Protozoan/genetics
- Antigens, Protozoan/immunology
- Cells, Cultured
- Conserved Sequence/immunology
- Epitope Mapping
- Epitopes/genetics
- Epitopes/immunology
- Immunity, Humoral
- Malaria Vaccines/chemistry
- Malaria Vaccines/immunology
- Membrane Proteins/chemistry
- Membrane Proteins/genetics
- Membrane Proteins/immunology
- Mice
- Mice, Nude
- Models, Molecular
- Plasmodium berghei/genetics
- Plasmodium berghei/immunology
- Plasmodium falciparum/immunology
- Protein Structure, Tertiary
- Protozoan Proteins/chemistry
- Protozoan Proteins/genetics
- Protozoan Proteins/immunology
- Rabbits
- Recombinant Fusion Proteins/chemistry
- Recombinant Fusion Proteins/immunology
Collapse
Affiliation(s)
- Sheetij Dutta
- Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
- * E-mail:
| | - Lisa S. Dlugosz
- Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | | | - Xiopeng Ge
- Department of Biochemistry, La Trobe University, Victoria, Australia
| | - Diouf Ababacar
- Laboratory of Malaria and Vector Research, National Institutes of Health, Rockville, Maryland, United States of America
| | - Yazmin I. Rovira
- Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - J. Kathleen Moch
- Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Meng Shi
- Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Carole A. Long
- Laboratory of Malaria and Vector Research, National Institutes of Health, Rockville, Maryland, United States of America
| | - Michael Foley
- Department of Biochemistry, La Trobe University, Victoria, Australia
| | | | - Robin F. Anders
- Department of Biochemistry, La Trobe University, Victoria, Australia
| | - Kazutoyo Miura
- Laboratory of Malaria and Vector Research, National Institutes of Health, Rockville, Maryland, United States of America
| | - J. David Haynes
- Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| | - Adrian H. Batchelor
- Walter Reed Army Institute of Research, Silver Spring, Maryland, United States of America
| |
Collapse
|
210
|
Kwong PD, Mascola JR, Nabel GJ. Broadly neutralizing antibodies and the search for an HIV-1 vaccine: the end of the beginning. Nat Rev Immunol 2013; 13:693-701. [PMID: 23969737 DOI: 10.1038/nri3516] [Citation(s) in RCA: 256] [Impact Index Per Article: 23.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The field of HIV-1 vaccine research has seen a renaissance with the identification of antibodies that neutralize most circulating HIV-1 strains. An understanding of the structural mode of target recognition that these antibodies use and the immune pathways that lead to their development is emerging. This knowledge has provided fundamental insights into the pathways that elicit broadly neutralizing antibodies and provides a foundation for active and passive immunization strategies to prevent HIV-1 infection.
Collapse
Affiliation(s)
- Peter D Kwong
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, US National Institutes of Health, Bethesda, Maryland 20892, USA
| | | | | |
Collapse
|
211
|
Lacerda M, Moore PL, Ngandu NK, Seaman M, Gray ES, Murrell B, Krishnamoorthy M, Nonyane M, Madiga M, Wibmer CK, Sheward D, Bailer RT, Gao H, Greene KM, Karim SSA, Mascola JR, Korber BTM, Montefiori DC, Morris L, Williamson C, Seoighe C. Identification of broadly neutralizing antibody epitopes in the HIV-1 envelope glycoprotein using evolutionary models. Virol J 2013; 10:347. [PMID: 24295501 PMCID: PMC4220805 DOI: 10.1186/1743-422x-10-347] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 11/21/2013] [Indexed: 11/19/2022] Open
Abstract
Background Identification of the epitopes targeted by antibodies that can neutralize diverse HIV-1 strains can provide important clues for the design of a preventative vaccine. Methods We have developed a computational approach that can identify key amino acids within the HIV-1 envelope glycoprotein that influence sensitivity to broadly cross-neutralizing antibodies. Given a sequence alignment and neutralization titers for a panel of viruses, the method works by fitting a phylogenetic model that allows the amino acid frequencies at each site to depend on neutralization sensitivities. Sites at which viral evolution influences neutralization sensitivity were identified using Bayes factors (BFs) to compare the fit of this model to that of a null model in which sequences evolved independently of antibody sensitivity. Conformational epitopes were identified with a Metropolis algorithm that searched for a cluster of sites with large Bayes factors on the tertiary structure of the viral envelope. Results We applied our method to ID50 neutralization data generated from seven HIV-1 subtype C serum samples with neutralization breadth that had been tested against a multi-clade panel of 225 pseudoviruses for which envelope sequences were also available. For each sample, between two and four sites were identified that were strongly associated with neutralization sensitivity (2ln(BF) > 6), a subset of which were experimentally confirmed using site-directed mutagenesis. Conclusions Our results provide strong support for the use of evolutionary models applied to cross-sectional viral neutralization data to identify the epitopes of serum antibodies that confer neutralization breadth.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Cathal Seoighe
- School of Mathematics, Statistics and Applied Mathematics, National University of Ireland Galway, Galway, Ireland.
| | | |
Collapse
|
212
|
Wood NT, Fadda E, Davis R, Grant OC, Martin JC, Woods RJ, Travers SA. The influence of N-linked glycans on the molecular dynamics of the HIV-1 gp120 V3 loop. PLoS One 2013; 8:e80301. [PMID: 24303005 PMCID: PMC3841175 DOI: 10.1371/journal.pone.0080301] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Accepted: 10/11/2013] [Indexed: 02/07/2023] Open
Abstract
N-linked glycans attached to specific amino acids of the gp120 envelope trimer of a HIV virion can modulate the binding affinity of gp120 to CD4, influence coreceptor tropism, and play an important role in neutralising antibody responses. Because of the challenges associated with crystallising fully glycosylated proteins, most structural investigations have focused on describing the features of a non-glycosylated HIV-1 gp120 protein. Here, we use a computational approach to determine the influence of N-linked glycans on the dynamics of the HIV-1 gp120 protein and, in particular, the V3 loop. We compare the conformational dynamics of a non-glycosylated gp120 structure to that of two glycosylated gp120 structures, one with a single, and a second with five, covalently linked high-mannose glycans. Our findings provide a clear illustration of the significant effect that N-linked glycosylation has on the temporal and spatial properties of the underlying protein structure. We find that glycans surrounding the V3 loop modulate its dynamics, conferring to the loop a marked propensity towards a more narrow conformation relative to its non-glycosylated counterpart. The conformational effect on the V3 loop provides further support for the suggestion that N-linked glycosylation plays a role in determining HIV-1 coreceptor tropism.
Collapse
Affiliation(s)
- Natasha T. Wood
- South African National Bioinformatics Institute, South African Medical Research Council Bioinformatics Unit, University of the Western Cape, Cape Town, South Africa
| | - Elisa Fadda
- Department of Chemistry, National University of Ireland, Maynooth, Maynooth, Ireland
| | - Robert Davis
- Complex Carbohydrate Research Centre, University of Georgia, Athens, Georgia, United States of America
| | - Oliver C. Grant
- School of Chemistry, National University of Ireland, Galway, Galway, Ireland
| | - Joanne C. Martin
- School of Chemistry, National University of Ireland, Galway, Galway, Ireland
| | - Robert J. Woods
- Complex Carbohydrate Research Centre, University of Georgia, Athens, Georgia, United States of America
- School of Chemistry, National University of Ireland, Galway, Galway, Ireland
| | - Simon A. Travers
- South African National Bioinformatics Institute, South African Medical Research Council Bioinformatics Unit, University of the Western Cape, Cape Town, South Africa
| |
Collapse
|
213
|
Palaia JM, McConnell M, Achenbach JE, Gustafson CE, Stoermer KA, Nolan M, Guay LA, Leitner TK, Matovu F, Taylor AW, Fowler MG, Janoff EN. Neutralization of HIV subtypes A and D by breast milk IgG from women with HIV infection in Uganda. J Infect 2013; 68:264-72. [PMID: 24239588 DOI: 10.1016/j.jinf.2013.11.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 11/01/2013] [Accepted: 11/07/2013] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Among HIV-exposed infants in resource-limited countries, 8-12% are infected postnatally by breastfeeding. However, most of those uninfected at birth remain uninfected over time despite daily exposure to HIV in breast milk. Thus, we assessed the HIV-inhibitory activity of breast milk. METHODS We measured cross-clade neutralization in activated PBMC of Ugandan subtype A (92UG031) and D (92UG005) primary HIV by breast milk or purified milk IgG and IgA from 25 HIV-infected Ugandan women. Isotype-specific antigen recognition was resolved by immunoblot. We determined HIV subtype from envelope population sequences in cells from 13 milk samples by PCR. RESULTS Milk inhibited p24 production by ≥50% (dose-dependent) by subtype A (21/25; 84%) and subtype D (11/25; 44%). IgG consistently reacted with multiple HIV antigens, including gp120/gp41, but IgA primarily recognized p24 alone. Depletion of IgG (n = 5), not IgA, diminished neutralization (mean 78 ± 33%) that was largely restored by IgG repletion. Mothers infected with subtype A more effectively neutralized subtype A than D. CONCLUSIONS Breast milk from HIV-infected women showed homotypic and cross-subtype neutralization of HIV by IgG-dependent and -independent mechanisms. These data direct further investigations into mechanisms of resistance against postnatal transmission of HIV to infants from their mothers.
Collapse
Affiliation(s)
- Jana M Palaia
- Mucosal and Vaccine Research Colorado (MAVRC), University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Denver Veterans Affairs Medical Center, Denver, CO 80220, USA
| | | | - Jenna E Achenbach
- Mucosal and Vaccine Research Colorado (MAVRC), University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Claire E Gustafson
- Mucosal and Vaccine Research Colorado (MAVRC), University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Denver Veterans Affairs Medical Center, Denver, CO 80220, USA
| | - Kristina A Stoermer
- Mucosal and Vaccine Research Colorado (MAVRC), University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Monica Nolan
- Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | - Laura A Guay
- Makerere University - Johns Hopkins University, Kampala, Uganda
| | | | - Flavia Matovu
- Makerere University - Johns Hopkins University, Kampala, Uganda
| | - Allan W Taylor
- Centers for Disease Control and Prevention, Atlanta, GA 30333, USA
| | | | - Edward N Janoff
- Mucosal and Vaccine Research Colorado (MAVRC), University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA; Denver Veterans Affairs Medical Center, Denver, CO 80220, USA.
| |
Collapse
|
214
|
Malaspina A, Collins BS, Dell A, Alter G, Onami TM. Conference report: "Functional Glycomics in HIV Type 1 Vaccine Design" workshop report, Bethesda, Maryland, April 30-May 1, 2012. AIDS Res Hum Retroviruses 2013; 29:1407-17. [PMID: 23767872 DOI: 10.1089/aid.2013.0102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
A vital part of the renewed hope for a vaccine against the human immunodeficiency virus (HIV-1) is based on recent studies that have highlighted major sites of HIV-1 vulnerability that could be effectively targeted by a preventive vaccine. One of these potential vulnerabilities includes the dense cluster of carbohydrates surrounding HIV-1's envelope glycoproteins gp120 and gp41, typically referred to as the "glycan shield." Recent data from several laboratories have shown that glycans on the HIV-1 envelope form key epitopes for broadly neutralizing antibodies (bNAb). Moreover, HIV-1 envelope glycans play an important role in viral transmission, antigenicity, and immunogenicity. The recent availability of novel tools and technologies has now allowed investigators to leverage glycomic structure-function relationships in the design of candidate HIV-1 vaccines. Additionally, glycans modulate the immune response, playing an essential role in Fc receptor and complement activity. To promote cross-disciplinary collaboration and promote synergistic HIV-1- glycomics research, the National Institutes of Health (NIH) cosponsored and convened a 1.5-day workshop entitled "Functional Glycomics in HIV-1 Vaccine Design." The meeting focused on the role of glycan interactions with neutralizing antibodies, the influence of immunoglobulin G (IgG) Fc receptor glycosylation, newly available glycomics technologies, and how new information on the role of glycans could be applied in HIV-1 immunogen design strategies. This report summarizes the discussions of this workshop.
Collapse
Affiliation(s)
- Angela Malaspina
- Preclinical Research and Development Branch, Division of AIDS, U.S. National Institute of Allergy and Infectious Diseases, Bethesda, Maryland
| | - Brenda S. Collins
- HJF-DAIDS, a Division of The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Contractor to NIAID, NIH, DHHS, Bethesda, Maryland
| | - Anne Dell
- Division of Molecular Biosciences, Imperial College London, London, United Kingdom
| | - Galit Alter
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Charlestown, Massachusetts
| | - Thandi M. Onami
- Vaccine Clinical Research Branch, Division of AIDS, U.S. National Institute of Allergy and Infectious Diseases, Bethesda, Maryland
| |
Collapse
|
215
|
Braibant M, Barin F. The role of neutralizing antibodies in prevention of HIV-1 infection: what can we learn from the mother-to-child transmission context? Retrovirology 2013; 10:103. [PMID: 24099103 PMCID: PMC3851888 DOI: 10.1186/1742-4690-10-103] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Accepted: 09/10/2013] [Indexed: 01/12/2023] Open
Abstract
In most viral infections, protection through existing vaccines is linked to the presence of vaccine-induced neutralizing antibodies (NAbs). However, more than 30 years after the identification of AIDS, the design of an immunogen able to induce antibodies that would neutralize the highly diverse HIV-1 variants remains one of the most puzzling challenges of the human microbiology. The role of antibodies in protection against HIV-1 can be studied in a natural situation that is the mother-to-child transmission (MTCT) context. Indeed, at least at the end of pregnancy, maternal antibodies of the IgG class are passively transferred to the fetus protecting the neonate from new infections during the first weeks or months of life. During the last few years, strong data, presented in this review, have suggested that some NAbs might confer protection toward neonatal HIV-1 infection. In cases of transmission, it has been shown that the viral population that is transmitted from the mother to the infant is usually homogeneous, genetically restricted and resistant to the maternal HIV-1-specific antibodies. Although the breath of neutralization was not associated with protection, it has not been excluded that NAbs toward specific HIV-1 strains might be associated with a lower rate of MTCT. A better identification of the antibody specificities that could mediate protection toward MTCT of HIV-1 would provide important insights into the antibody responses that would be useful for vaccine development. The most convincing data suggesting that NAbs migh confer protection against HIV-1 infection have been obtained by experiments of passive immunization of newborn macaques with the first generation of human monoclonal broadly neutralizing antibodies (HuMoNAbs). However, these studies, which included only a few selected subtype B challenge viruses, provide data limited to protection against a very restricted number of isolates and therefore have limitations in addressing the hypervariability of HIV-1. The recent identification of highly potent second-generation cross-clade HuMoNAbs provides a new opportunity to evaluate the efficacy of passive immunization to prevent MTCT of HIV-1.
Collapse
Affiliation(s)
- Martine Braibant
- Université François-Rabelais, UFR Médecine, Inserm U966 10 bld Tonnellé, cedex, 37032 Tours, France.
| | | |
Collapse
|
216
|
Wibmer CK, Bhiman JN, Gray ES, Tumba N, Abdool Karim SS, Williamson C, Morris L, Moore PL. Viral escape from HIV-1 neutralizing antibodies drives increased plasma neutralization breadth through sequential recognition of multiple epitopes and immunotypes. PLoS Pathog 2013; 9:e1003738. [PMID: 24204277 PMCID: PMC3814426 DOI: 10.1371/journal.ppat.1003738] [Citation(s) in RCA: 168] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2013] [Accepted: 09/14/2013] [Indexed: 11/30/2022] Open
Abstract
Identifying the targets of broadly neutralizing antibodies to HIV-1 and understanding how these antibodies develop remain important goals in the quest to rationally develop an HIV-1 vaccine. We previously identified a participant in the CAPRISA Acute Infection Cohort (CAP257) whose plasma neutralized 84% of heterologous viruses. In this study we showed that breadth in CAP257 was largely due to the sequential, transient appearance of three distinct broadly neutralizing antibody specificities spanning the first 4.5 years of infection. The first specificity targeted an epitope in the V2 region of gp120 that was also recognized by strain-specific antibodies 7 weeks earlier. Specificity for the autologous virus was determined largely by a rare N167 antigenic variant of V2, with viral escape to the more common D167 immunotype coinciding with the development of the first wave of broadly neutralizing antibodies. Escape from these broadly neutralizing V2 antibodies through deletion of the glycan at N160 was associated with exposure of an epitope in the CD4 binding site that became the target for a second wave of broadly neutralizing antibodies. Neutralization by these CD4 binding site antibodies was almost entirely dependent on the glycan at position N276. Early viral escape mutations in the CD4 binding site drove an increase in wave two neutralization breadth, as this second wave of heterologous neutralization matured to recognize multiple immunotypes within this site. The third wave targeted a quaternary epitope that did not overlap any of the four known sites of vulnerability on the HIV-1 envelope and remains undefined. Altogether this study showed that the human immune system is capable of generating multiple broadly neutralizing antibodies in response to a constantly evolving viral population that exposes new targets as a consequence of escape from earlier neutralizing antibodies.
Collapse
Affiliation(s)
- Constantinos Kurt Wibmer
- Centre for HIV and STIs, National Institute for Communicable Diseases (NICD), of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Jinal N. Bhiman
- Centre for HIV and STIs, National Institute for Communicable Diseases (NICD), of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Elin S. Gray
- Centre for HIV and STIs, National Institute for Communicable Diseases (NICD), of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Nancy Tumba
- Centre for HIV and STIs, National Institute for Communicable Diseases (NICD), of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
| | - Salim S. Abdool Karim
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), University of KwaZulu-Natal, Durban, South Africa
| | - Carolyn Williamson
- Institute of Infectious Disease and Molecular Medicine (IIDMM) and Division of Medical Virology, University of Cape Town and NHLS, Cape Town, South Africa
| | - Lynn Morris
- Centre for HIV and STIs, National Institute for Communicable Diseases (NICD), of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Penny L. Moore
- Centre for HIV and STIs, National Institute for Communicable Diseases (NICD), of the National Health Laboratory Service (NHLS), Johannesburg, South Africa
- Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| |
Collapse
|
217
|
van den Kerkhof TLGM, Feenstra KA, Euler Z, van Gils MJ, Rijsdijk LWE, Boeser-Nunnink BD, Heringa J, Schuitemaker H, Sanders RW. HIV-1 envelope glycoprotein signatures that correlate with the development of cross-reactive neutralizing activity. Retrovirology 2013; 10:102. [PMID: 24059682 PMCID: PMC3849187 DOI: 10.1186/1742-4690-10-102] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Accepted: 09/12/2013] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Current HIV-1 envelope glycoprotein (Env) vaccines are unable to induce cross-reactive neutralizing antibodies. However, such antibodies are elicited in 10-30% of HIV-1 infected individuals, but it is unknown why these antibodies are induced in some individuals and not in others. We hypothesized that the Envs of early HIV-1 variants in individuals who develop cross-reactive neutralizing activity (CrNA) might have unique characteristics that support the induction of CrNA. RESULTS We retrospectively generated and analyzed env sequences of early HIV-1 clonal variants from 31 individuals with diverse levels of CrNA 2-4 years post-seroconversion. These sequences revealed a number of Env signatures that coincided with CrNA development. These included a statistically shorter variable region 1 and a lower probability of glycosylation as implied by a high ratio of NXS versus NXT glycosylation motifs. Furthermore, lower probability of glycosylation at position 332, which is involved in the epitopes of many broadly reactive neutralizing antibodies, was associated with the induction of CrNA. Finally, Sequence Harmony identified a number of amino acid changes associated with the development of CrNA. These residues mapped to various Env subdomains, but in particular to the first and fourth variable region as well as the underlying α2 helix of the third constant region. CONCLUSIONS These findings imply that the development of CrNA might depend on specific characteristics of early Env. Env signatures that correlate with the induction of CrNA might be relevant for the design of effective HIV-1 vaccines.
Collapse
Affiliation(s)
- Tom L G M van den Kerkhof
- Department of Experimental Immunology and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - K Anton Feenstra
- Center for Integrative Bioinformatics VU (IBIVU) and Amsterdam Institute for Molecules, Medicine and Systems (AIMMS), VU University Amsterdam, 1081 HV Amsterdam, the Netherlands
- Netherlands Bioinformatics Center (NBIC), 6525 GA Nijmegen, the Netherlands
| | - Zelda Euler
- Department of Experimental Immunology and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Marit J van Gils
- Department of Experimental Immunology and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Linda W E Rijsdijk
- Center for Integrative Bioinformatics VU (IBIVU) and Amsterdam Institute for Molecules, Medicine and Systems (AIMMS), VU University Amsterdam, 1081 HV Amsterdam, the Netherlands
| | - Brigitte D Boeser-Nunnink
- Department of Experimental Immunology and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Jaap Heringa
- Center for Integrative Bioinformatics VU (IBIVU) and Amsterdam Institute for Molecules, Medicine and Systems (AIMMS), VU University Amsterdam, 1081 HV Amsterdam, the Netherlands
- Netherlands Bioinformatics Center (NBIC), 6525 GA Nijmegen, the Netherlands
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
| | - Hanneke Schuitemaker
- Department of Experimental Immunology and Landsteiner Laboratory, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
- Crucell Holland BV, 2333 CN Leiden, the Netherlands
| | - Rogier W Sanders
- Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, the Netherlands
- Department of Microbiology and Immunology, Weill Medical College, Cornell University, New York, NY 10065 USA
| |
Collapse
|
218
|
Klein F, Mouquet H, Dosenovic P, Scheid JF, Scharf L, Nussenzweig MC. Antibodies in HIV-1 vaccine development and therapy. Science 2013; 341:1199-204. [PMID: 24031012 DOI: 10.1126/science.1241144] [Citation(s) in RCA: 357] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Despite 30 years of study, there is no HIV-1 vaccine and, until recently, there was little hope for a protective immunization. Renewed optimism in this area of research comes in part from the results of a recent vaccine trial and the use of single-cell antibody-cloning techniques that uncovered naturally arising, broad and potent HIV-1-neutralizing antibodies (bNAbs). These antibodies can protect against infection and suppress established HIV-1 infection in animal models. The finding that these antibodies develop in a fraction of infected individuals supports the idea that new approaches to vaccination might be developed by adapting the natural immune strategies or by structure-based immunogen design. Moreover, the success of passive immunotherapy in small-animal models suggests that bNAbs may become a valuable addition to the armamentarium of drugs that work against HIV-1.
Collapse
Affiliation(s)
- Florian Klein
- Laboratory of Molecular Immunology, The Rockefeller University, New York, NY 10065, USA.
| | | | | | | | | | | |
Collapse
|
219
|
Rabbit anti-HIV-1 monoclonal antibodies raised by immunization can mimic the antigen-binding modes of antibodies derived from HIV-1-infected humans. J Virol 2013; 87:10221-31. [PMID: 23864637 PMCID: PMC3754018 DOI: 10.1128/jvi.00843-13] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The rabbit is a commonly used animal model in studying antibody responses in HIV/AIDS vaccine development. However, no rabbit monoclonal antibodies (MAbs) have been developed previously to study the epitope-specific antibody responses against HIV-1 envelope (Env) glycoproteins, and little is known about how the rabbit immune system can mimic the human immune system in eliciting such antibodies. Here we present structural analyses of two rabbit MAbs, R56 and R20, against the third variable region (V3) of HIV-1 gp120. R56 recognizes the well-studied immunogenic region in the V3 crown, while R20 targets a less-studied region at the C terminus of V3. By comparison of the Fab/epitope complex structures of these two antibodies raised by immunization with that of the corresponding human antibodies derived from patients chronically infected with HIV-1, we found that rabbit antibodies can recognize immunogenic regions of gp120 and mimic the binding modes of human antibodies. This result can provide new insight into the use of the rabbit as an animal model in AIDS vaccine development.
Collapse
|
220
|
Host-pathogen interaction in HIV infection. Curr Opin Immunol 2013; 25:463-9. [PMID: 23890585 DOI: 10.1016/j.coi.2013.07.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 06/26/2013] [Accepted: 07/04/2013] [Indexed: 12/24/2022]
Abstract
The host-pathogen interaction is strikingly complex during HIV infection. While several immune effector mechanisms (i.e. cytotoxic T cells, neutralizing antibodies, NK cells, among others) can play a strong antiviral role in vivo, the virus is remarkably able to evade these responses. In addition, the virus preferentially infects and kills activated memory CD4+ T cells, thus exploiting the host antiviral immune response as a source of new cellular targets for infection. Recent advances in understanding (i) how HIV perturbs the host immune system, (ii) how the immune system fights HIV; and (iii) how HIV disease persists when virus replication is suppressed by antiretroviral drugs may hopefully lead to better prevention and treatment strategies for this deadly viral infection.
Collapse
|
221
|
Balla-Jhagjhoorsingh SS, Corti D, Heyndrickx L, Willems E, Vereecken K, Davis D, Vanham G. The N276 glycosylation site is required for HIV-1 neutralization by the CD4 binding site specific HJ16 monoclonal antibody. PLoS One 2013; 8:e68863. [PMID: 23874792 PMCID: PMC3714269 DOI: 10.1371/journal.pone.0068863] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 05/31/2013] [Indexed: 11/19/2022] Open
Abstract
Immunogen design for HIV-1 vaccines could be based on epitope identification of naturally occurring neutralizing antibodies in infected patients. A tier 2 neutralizing monoclonal antibody (mAb), HJ16 recognizes a new epitope in the CD4 binding site (CD4bs) region that only partially overlaps with the b12 epitope. We aimed to identify the critical binding site by resistance induction in a sensitive primary CRF02_AG strain. In four independent dose-escalation studies, the N276D mutation was consistently the only alteration found and it was confirmed to be responsible for resistance to HJ16 by site-directed mutagenesis in envelopes (envs) of the homologous CRF02_AG, as well as of a subtype A and a subtype C primary isolate. This mutation removes an N-linked glycosylation site. The effect of N276D was very selective, as it failed to confer resistance to a range of other entry inhibitors. Remarkably, sensitivity to the CD4bs VRC01 and VRC03 mAbs was increased in the N276D mutated viruses. These data indicate that binding of the CD4bs specific HJ16 mAb critically depends on the interaction with the N276-glycan, thus indicating that HJ16 is the first glycan dependent CD4bs-specific mAb.
Collapse
|
222
|
HIV-1 autologous antibody neutralization associates with mother to child transmission. PLoS One 2013; 8:e69274. [PMID: 23874931 PMCID: PMC3714266 DOI: 10.1371/journal.pone.0069274] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Accepted: 06/06/2013] [Indexed: 01/07/2023] Open
Abstract
The HIV-1 characteristics associated with mother to child transmission (MTCT) are still poorly understood and if known would indicate where intervention strategies should be targeted. In contrast to horizontally infected individuals, exposed infants possess inherited antibodies (Abs) from their mother with the potential to protect against infection. We investigated the HIV-1 gp160 envelope proteins from seven transmitting mothers (TM) whose children were infected either during gestation or soon after delivery and from four non-transmitting mothers (NTM) with similar viral loads and CD4 counts. Using pseudo-typed viruses we tested gp160 envelope glycoproteins for TZM-bl infectivity, CD4 and CCR5 interactions, DC-SIGN capture and transfer and neutralization with an array of common neutralizing Abs (NAbs) (2F5, 2G12, 4E10 and b12) as well as mother and infant plasma. We found no viral correlates associated with HIV-1 MTCT nor did we find differences in neutralization with the panel of NAbs. We did, however, find that TM possessed significantly higher plasma neutralization capacities than NTM (P = 0.002). Furthermore, we found that in utero (IU) TM had a higher neutralization capacity than mothers transmitting either peri-partum (PP) or via breastfeeding (BF) (P = 0.002). Plasma from children infected IU neutralized viruses carrying autologous gp160 viral envelopes as well as those from their corresponding mothers whilst plasma from children infected PP and/or BF demonstrated poor neutralizing capacity. Our results demonstrate heightened autologous NAb responses against gp120/gp41 can associate with a greater risk of HIV-1 MTCT and more specifically in those infants infected IU. Although the number of HIV-1 transmitting pairs is low our results indicate that autologous NAb responses in mothers and infants do not protect against MTCT and may in fact be detrimental when considering IU HIV-1 transmissions.
Collapse
|
223
|
Abstract
The development of an effective vaccine has been hindered by the enormous diversity of human immunodeficiency virus-1 (HIV-1) and its ability to escape a myriad of host immune responses. In addition, conserved vulnerable regions on the HIV-1 envelope glycoprotein are often poorly immunogenic and elicit broadly neutralizing antibody responses (BNAbs) in a minority of HIV-1-infected individuals and only after several years of infection. All of the known BNAbs demonstrate high levels of somatic mutations and often display other unusual traits, such as a long heavy chain complementarity determining region 3 (CDRH3) and autoreactivity that can be limited by host tolerance controls. Nonetheless, the demonstration that HIV-1-infected individuals can make potent BNAbs is encouraging, and recent progress in isolating such antibodies and mapping their immune pathways of development is providing new strategies for vaccination.
Collapse
Affiliation(s)
- John R Mascola
- Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, MD, USA.
| | | |
Collapse
|
224
|
Ping LH, Joseph SB, Anderson JA, Abrahams MR, Salazar-Gonzalez JF, Kincer LP, Treurnicht FK, Arney L, Ojeda S, Zhang M, Keys J, Potter EL, Chu H, Moore P, Salazar MG, Iyer S, Jabara C, Kirchherr J, Mapanje C, Ngandu N, Seoighe C, Hoffman I, Gao F, Tang Y, Labranche C, Lee B, Saville A, Vermeulen M, Fiscus S, Morris L, Karim SA, Haynes BF, Shaw GM, Korber BT, Hahn BH, Cohen MS, Montefiori D, Williamson C, Swanstrom R. Comparison of viral Env proteins from acute and chronic infections with subtype C human immunodeficiency virus type 1 identifies differences in glycosylation and CCR5 utilization and suggests a new strategy for immunogen design. J Virol 2013; 87:7218-33. [PMID: 23616655 PMCID: PMC3700278 DOI: 10.1128/jvi.03577-12] [Citation(s) in RCA: 95] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 04/15/2013] [Indexed: 12/18/2022] Open
Abstract
Understanding human immunodeficiency virus type 1 (HIV-1) transmission is central to developing effective prevention strategies, including a vaccine. We compared phenotypic and genetic variation in HIV-1 env genes from subjects in acute/early infection and subjects with chronic infections in the context of subtype C heterosexual transmission. We found that the transmitted viruses all used CCR5 and required high levels of CD4 to infect target cells, suggesting selection for replication in T cells and not macrophages after transmission. In addition, the transmitted viruses were more likely to use a maraviroc-sensitive conformation of CCR5, perhaps identifying a feature of the target T cell. We confirmed an earlier observation that the transmitted viruses were, on average, modestly underglycosylated relative to the viruses from chronically infected subjects. This difference was most pronounced in comparing the viruses in acutely infected men to those in chronically infected women. These features of the transmitted virus point to selective pressures during the transmission event. We did not observe a consistent difference either in heterologous neutralization sensitivity or in sensitivity to soluble CD4 between the two groups, suggesting similar conformations between viruses from acute and chronic infection. However, the presence or absence of glycosylation sites had differential effects on neutralization sensitivity for different antibodies. We suggest that the occasional absence of glycosylation sites encoded in the conserved regions of env, further reduced in transmitted viruses, could expose specific surface structures on the protein as antibody targets.
Collapse
Affiliation(s)
- Li-Hua Ping
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Sarah B. Joseph
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jeffrey A. Anderson
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Melissa-Rose Abrahams
- Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and National Health Laboratory Services, Cape Town, South Africa
| | | | - Laura P. Kincer
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Florette K. Treurnicht
- Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and National Health Laboratory Services, Cape Town, South Africa
| | - Leslie Arney
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Suany Ojeda
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Ming Zhang
- Theoretical Biology, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
- Department of Epidemiology and Biostatistics, University of Georgia, Athens, Georgia, USA
| | - Jessica Keys
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - E. Lake Potter
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Haitao Chu
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Penny Moore
- Centre for HIV and STIs, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Maria G. Salazar
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Shilpa Iyer
- Departments of Medicine and Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Cassandra Jabara
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Jennifer Kirchherr
- Duke Human Vaccine Institute, Department of Medicine, Duke University, Durham, North Carolina, USA
| | | | - Nobubelo Ngandu
- Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and National Health Laboratory Services, Cape Town, South Africa
| | | | - Irving Hoffman
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Feng Gao
- Duke Human Vaccine Institute, Department of Medicine, Duke University, Durham, North Carolina, USA
| | - Yuyang Tang
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Celia Labranche
- Department of Surgery, Duke University, Durham, North Carolina, USA
| | - Benhur Lee
- Department of Microbiology, Immunology and Molecular Genetics, University of California at Los Angeles, Los Angeles, California, USA
| | - Andrew Saville
- South African National Blood Service, Weltevreden Park, South Africa
| | - Marion Vermeulen
- South African National Blood Service, Weltevreden Park, South Africa
| | - Susan Fiscus
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Lynn Morris
- Centre for HIV and STIs, National Institute for Communicable Diseases, Johannesburg, South Africa
| | - Salim Abdool Karim
- Center for AIDS Program Research in South Africa, Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban, South Africa
| | - Barton F. Haynes
- Duke Human Vaccine Institute, Department of Medicine, Duke University, Durham, North Carolina, USA
| | - George M. Shaw
- Departments of Medicine and Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Bette T. Korber
- Los Alamos National Laboratory, Los Alamos, New Mexico, USA
- Santa Fe Institute, Santa Fe, New Mexico, USA
| | - Beatrice H. Hahn
- Departments of Medicine and Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Myron S. Cohen
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Division of Infectious Diseases, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - David Montefiori
- Department of Surgery, Duke University, Durham, North Carolina, USA
| | - Carolyn Williamson
- Institute of Infectious Diseases and Molecular Medicine, Division of Medical Virology, University of Cape Town and National Health Laboratory Services, Cape Town, South Africa
| | - Ronald Swanstrom
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| |
Collapse
|
225
|
Jennifer M, Leslie G, Maxwel MO, Ruth N, Julie O. HIV-1 maternal and infant variants show similar sensitivity to broadly neutralizing antibodies, but sensitivity varies by subtype. AIDS 2013; 27:1535-44. [PMID: 23856624 PMCID: PMC4080909 DOI: 10.1097/qad.0b013e32835faba5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
RATIONALE To protect against HIV infection, passively transferred and/or vaccine-elicited neutralizing antibodies (NAbs) need to effectively target diverse subtypes that are transmitted globally. These variants are a limited subset of those present during chronic infection and display some unique features. In the case of mother-to-child transmission (MTCT), transmitted variants tend to be resistant to neutralization by maternal autologous NAbs. METHOD To investigate whether variants transmitted during MTCT are generally resistant to HIV-1-specific NAbs, 107 maternal or infant variants representing the dominant HIV-1 subtypes were tested against six recently identified HIV-1-specific broadly neutralizing monoclonal antibodies (bNAbs), NIH45-46W, VRC01, PGT128, PGT121, PG9 and PGT145. RESULTS Infant and maternal variants did not differ in their neutralization sensitivity to individual bNAbs, nor did viruses from transmitting versus nontransmitting mothers, although there was a trend for viruses from transmitting mothers to be less sensitive overall. No single bNAb neutralized all viruses, but a combination of bNAbs that target distinct epitopes covered 100% of the variants tested. Compared with heterosexually transmitted variants, vertically transmitted variants were significantly more sensitive to neutralization by PGT128 and PGT121 (P=0.03 in both cases), but there were no differences for the other bNAbs. Overall, subtype A variants were significantly more sensitive to NIH45-46 (P=0.04), VRC01 (P=0.002) and PGT145 (P=0.03) compared with the nonsubtype A and less sensitive to PGT121 than subtype Cs (P=0.0001). CONCLUSION A combination of bNAbs against distinct epitopes may be needed to provide maximum coverage against viruses in different modes of transmission and diverse subtypes.
Collapse
Affiliation(s)
- Mabuka Jennifer
- Division of Human Biology and Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, US 98109
- Program of Pathobiology, Department of Global Health, University of Washington, Seattle, WA
| | - Goo Leslie
- Division of Human Biology and Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, US 98109
- Program of Pathobiology, Department of Global Health, University of Washington, Seattle, WA
| | - Majiwa O. Maxwel
- Division of Human Biology and Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, US 98109
- Program of Pathobiology, Department of Global Health, University of Washington, Seattle, WA
| | - Nduati Ruth
- Department of Pediatrics, University of Nairobi, Nairobi, Kenya
| | - Overbaugh Julie
- Division of Human Biology and Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington, US 98109
| |
Collapse
|
226
|
Pantua H, Diao J, Ultsch M, Hazen M, Mathieu M, McCutcheon K, Takeda K, Date S, Cheung TK, Phung Q, Hass P, Arnott D, Hongo JA, Matthews DJ, Brown A, Patel AH, Kelley RF, Eigenbrot C, Kapadia SB. Glycan Shifting on Hepatitis C Virus (HCV) E2 Glycoprotein Is a Mechanism for Escape from Broadly Neutralizing Antibodies. J Mol Biol 2013; 425:1899-1914. [DOI: 10.1016/j.jmb.2013.02.025] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 02/15/2013] [Accepted: 02/22/2013] [Indexed: 12/14/2022]
|
227
|
Kong L, Lee JH, Doores KJ, Murin CD, Julien JP, McBride R, Liu Y, Marozsan A, Cupo A, Klasse PJ, Hoffenberg S, Caulfield M, King CR, Hua Y, Le KM, Khayat R, Deller MC, Clayton T, Tien H, Feizi T, Sanders RW, Paulson JC, Moore JP, Stanfield RL, Burton DR, Ward AB, Wilson IA. Supersite of immune vulnerability on the glycosylated face of HIV-1 envelope glycoprotein gp120. Nat Struct Mol Biol 2013; 20:796-803. [PMID: 23708606 PMCID: PMC3823233 DOI: 10.1038/nsmb.2594] [Citation(s) in RCA: 279] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 04/05/2013] [Indexed: 12/17/2022]
Abstract
A substantial proportion of the broadly neutralizing antibodies (bnAbs) identified in certain HIV-infected donors recognize glycan-dependent epitopes on HIV-1 gp120. Here we elucidate how the bnAb PGT 135 binds its Asn332 glycan-dependent epitope from its 3.1-Å crystal structure with gp120, CD4 and Fab 17b. PGT 135 interacts with glycans at Asn332, Asn392 and Asn386, using long CDR loops H1 and H3 to penetrate the glycan shield and access the gp120 protein surface. EM reveals that PGT 135 can accommodate the conformational and chemical diversity of gp120 glycans by altering its angle of engagement. Combined structural studies of PGT 135, PGT 128 and 2G12 show that this Asn332-dependent antigenic region is highly accessible and much more extensive than initially appreciated, which allows for multiple binding modes and varied angles of approach; thereby it represents a supersite of vulnerability for antibody neutralization.
Collapse
Affiliation(s)
- Leopold Kong
- Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
228
|
Moore PL, Sheward D, Nonyane M, Ranchobe N, Hermanus T, Gray ES, Abdool Karim SS, Williamson C, Morris L. Multiple pathways of escape from HIV broadly cross-neutralizing V2-dependent antibodies. J Virol 2013; 87:4882-94. [PMID: 23408621 PMCID: PMC3624332 DOI: 10.1128/jvi.03424-12] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Accepted: 02/06/2013] [Indexed: 11/20/2022] Open
Abstract
Broadly cross-neutralizing (BCN) antibodies are likely to be critical for an effective HIV vaccine. However, the ontogeny of such antibodies and their relationship with autologous viral evolution is unclear. Here, we characterized viral evolution in CAP256, a subtype C-infected individual who developed potent BCN antibodies targeting positions R166 and K169 in the V2 region. CAP256 was superinfected at 3 months postinfection with a virus that was highly sensitive to BCN V2-dependent monoclonal antibodies. The autologous neutralizing response in CAP256 was directed at V1V2, reaching extremely high titers (>1:40,000) against the superinfecting virus at 42 weeks, just 11 weeks prior to the development of the BCN response targeting the same region. Recombination between the primary and superinfecting viruses, especially in V2 and gp41, resulted in two distinct lineages by 4 years postinfection. Although neutralization of some CAP256 clones by plasma from as much as 2 years earlier suggested incomplete viral escape, nonetheless titers against later clones were reduced at least 40-fold to less than 1:1,000. Escape mutations were identified in each lineage, either at R166 or at K169, suggesting that strain-specific and BCN antibodies targeted overlapping epitopes. Furthermore, the early dependence of CAP256 neutralizing antibodies on the N160 glycan decreased with the onset of neutralization breadth, indicating a change in specificity. These data suggest rapid maturation, within 11 weeks, of CAP256 strain-specific antibodies to acquire breadth, with implications for the vaccine elicitation of BCN V2-dependent antibodies. Overall these studies demonstrate that ongoing viral escape is possible, even from BCN antibodies.
Collapse
Affiliation(s)
- Penny L Moore
- Centre for HIV and STIs, National Institute for Communicable Diseases of the National Health Laboratory Services, Johannesburg, South Africa.
| | | | | | | | | | | | | | | | | |
Collapse
|
229
|
|
230
|
Abstract
The production of cross-reactive neutralizing antibodies is the ultimate goal in HIV vaccine development, but no immunogen other than HIV itself has been able to elicit this type of humoral immunity. In natural HIV infections, these antibodies take several years to develop. A new study sheds light on what may be causing this delay in neutralizing antibody development (pages 1688-1692).
Collapse
|
231
|
Generation of lineage-related, mucosally transmissible subtype C R5 simian-human immunodeficiency viruses capable of AIDS development, induction of neurological disease, and coreceptor switching in rhesus macaques. J Virol 2013; 87:6137-49. [PMID: 23514895 DOI: 10.1128/jvi.00178-13] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Most human immunodeficiency virus (HIV) transmissions are initiated with CCR5 (R5)-using viruses across mucosal surfaces, with the majority in regions where HIV type 1 (HIV-1) clade C predominates. Mucosally transmissible, highly replication competent, pathogenic R5 simian-human immunodeficiency viruses (SHIVs) encoding biologically relevant clade C envelopes are therefore needed as challenge viruses in vaccine efficacy studies with nonhuman primates. Here we describe the generation of three lineage-related subtype C SHIVs through four successive rapid transfers in rhesus macaques of SHIVC109F.PB4, a molecular clone expressing the soluble-CD4 (sCD4)-sensitive CCR5-tropic clade C envelope of a recently infected subject in Zambia. The viruses differed in their monkey passage histories and neutralization sensitivities but remained R5 tropic. SHIVC109P3 and SHIVC109P3N were recovered from a passage-3 rapid-progressor animal during chronic infection (24 weeks postinfection [wpi]) and at end-stage disease (34 wpi), respectively, and are classified as tier 1B strains, whereas SHIVC109P4 was recovered from a passage-4 normal-progressor macaque at 22 wpi and is a tier 2 virus, more difficult to neutralize. All three viruses were transmitted efficiently via intrarectal inoculation, reaching peak viral loads of 10(7) to 10(9) RNA copies/ml plasma and establishing viremia at various set points. Notably, one of seven (GC98) and two of six (CL31, FI08) SHIVC109P3- and SHIVC109P3N-infected macaques, respectively, progressed to AIDS, with neuropathologies observed in GC98 and FI08, as well as coreceptor switching in the latter. These findings support the use of these new SHIVC109F.PB4-derived viruses to study the immunopathology of HIV-1 clade C infection and to evaluate envelope-based AIDS vaccines in nonhuman primates.
Collapse
|
232
|
Girard MP, Picot V, Longuet C, Nabel GJ. Report of the Cent Gardes HIV Vaccine Conference: The B-cell Response to HIV. Part 1: Broadly Neutralizing Antibodies Fondation Mérieux Conference Center, Veyrier du Lac, France, 5-7 November 2012. Vaccine 2013; 31:2979-83. [PMID: 23499518 DOI: 10.1016/j.vaccine.2013.02.068] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Accepted: 02/27/2013] [Indexed: 02/04/2023]
Abstract
The Cent Gardes Conference on HIV Vaccines took place on November 5-7, 2012 at the Fondation Mérieux Conference Center, Annecy, France. The aim of the meeting was to review the B cell response to human immunodeficiency virus-1 (HIV-1) infection and immunization, from broadly neutralizing antibodies (bnAbs) to non-neutralizing antibodies (n-nAbs). The production of cross-reactive bnAbs is one of the greatest challenges in HIV-1 vaccine development. In natural HIV infection, bnAbs are observed in only a minority of infected individuals and take a few years to develop. This report presents a comprehensive review of how these Abs arise, the possible role of viral evolution, and the activation and maturation requirements of B cell lines that lead to their production. Passive immunization with bnAbs provides efficient, cross-clade protection against simian/human immunodeficiency chimeric virus (SHIV) challenges in nonhuman primates. Despite many efforts to design immunogens that elicit them by active immunization, no immunogen other than HIV itself has yet been able to elicit a bnAb response. For this reason, innovative approaches are under investigation, including their production in the body through a gene delivery approach, vector immunoprophylaxis.
Collapse
Affiliation(s)
- Marc P Girard
- French National Academy of Medicine, 16 rue Bonaparte, 75006 Paris, France.
| | | | | | | |
Collapse
|
233
|
Murphy MK, Yue L, Pan R, Boliar S, Sethi A, Tian J, Pfafferot K, Karita E, Allen SA, Cormier E, Goepfert PA, Borrow P, Robinson JE, Gnanakaran S, Hunter E, Kong XP, Derdeyn CA. Viral escape from neutralizing antibodies in early subtype A HIV-1 infection drives an increase in autologous neutralization breadth. PLoS Pathog 2013; 9:e1003173. [PMID: 23468623 PMCID: PMC3585129 DOI: 10.1371/journal.ppat.1003173] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Accepted: 12/19/2012] [Indexed: 01/07/2023] Open
Abstract
Antibodies that neutralize (nAbs) genetically diverse HIV-1 strains have been recovered from a subset of HIV-1 infected subjects during chronic infection. Exact mechanisms that expand the otherwise narrow neutralization capacity observed during early infection are, however, currently undefined. Here we characterized the earliest nAb responses in a subtype A HIV-1 infected Rwandan seroconverter who later developed moderate cross-clade nAb breadth, using (i) envelope (Env) glycoproteins from the transmitted/founder virus and twenty longitudinal nAb escape variants, (ii) longitudinal autologous plasma, and (iii) autologous monoclonal antibodies (mAbs). Initially, nAbs targeted a single region of gp120, which flanked the V3 domain and involved the alpha2 helix. A single amino acid change at one of three positions in this region conferred early escape. One immunoglobulin heavy chain and two light chains recovered from autologous B cells comprised two mAbs, 19.3H-L1 and 19.3H-L3, which neutralized the founder Env along with one or three of the early escape variants carrying these mutations, respectively. Neither mAb neutralized later nAb escape or heterologous Envs. Crystal structures of the antigen-binding fragments (Fabs) revealed flat epitope contact surfaces, where minimal light chain mutation in 19.3H-L3 allowed for additional antigenic interactions. Resistance to mAb neutralization arose in later Envs through alteration of two glycans spatially adjacent to the initial escape signatures. The cross-neutralizing nAbs that ultimately developed failed to target any of the defined V3-proximal changes generated during the first year of infection in this subject. Our data demonstrate that this subject's first recognized nAb epitope elicited strain-specific mAbs, which incrementally acquired autologous breadth, and directed later B cell responses to target distinct portions of Env. This immune re-focusing could have triggered the evolution of cross-clade antibodies and suggests that exposure to a specific sequence of immune escape variants might promote broad humoral responses during HIV-1 infection.
Collapse
Affiliation(s)
- Megan K. Murphy
- Immunology and Molecular Pathogenesis Graduate Program, Emory University, Atlanta, Georgia, United States of America
- Emory Vaccine Center at Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, United States of America
| | - Ling Yue
- Emory Vaccine Center at Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, United States of America
| | - Ruimin Pan
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York, United States of America
| | - Saikat Boliar
- Emory Vaccine Center at Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, United States of America
| | - Anurag Sethi
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
| | - Jianhui Tian
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
| | - Katja Pfafferot
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | | | - Susan A. Allen
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, United States of America
- Departments of Epidemiology and Global Health, Emory University, Atlanta, Georgia, United States of America
| | - Emmanuel Cormier
- International AIDS Vaccine Initiative, Human Immunology Laboratory, Imperial College, London, United Kingdom
| | - Paul A. Goepfert
- Departments of Medicine and Microbiology, University of Alabama at Birmingham, Birmingham, Alabama, United States of America
| | - Persephone Borrow
- Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - James E. Robinson
- Department of Pediatrics, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - S. Gnanakaran
- Theoretical Biology and Biophysics Group, Los Alamos National Laboratory, Los Alamos, New Mexico, United States of America
| | - Eric Hunter
- Emory Vaccine Center at Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, United States of America
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, United States of America
| | - Xiang-Peng Kong
- Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, New York, United States of America
| | - Cynthia A. Derdeyn
- Emory Vaccine Center at Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, United States of America
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia, United States of America
- * E-mail:
| |
Collapse
|
234
|
Travers SA. Conservation, Compensation, and Evolution of N-Linked Glycans in the HIV-1 Group M Subtypes and Circulating Recombinant Forms. ISRN AIDS 2012; 2012:823605. [PMID: 24052884 PMCID: PMC3765798 DOI: 10.5402/2012/823605] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/18/2012] [Accepted: 11/25/2012] [Indexed: 01/17/2023]
Abstract
The “glycan shield” exposed on the surface of the HIV-1 gp120 env glycoprotein has been previously proposed as a novel target for anti-HIV treatments. While such targeting of these glycans provides an exciting prospect for HIV treatment, little is known about the conservation and variability of glycosylation patterns within and between the various HIV-1 group M subtypes and circulating recombinant forms. Here, we present evidence of strong strain-specific glycosylation patterns and show that the epitope for the 2G12 neutralising antibody is poorly conserved across HIV-1 group M. The unique glycosylation patterns within the HIV-1 group M subtypes and CRFs appear to explain their varying susceptibility to neutralisation by broadly cross-neutralising (BCN) antibodies. Compensatory glycosylation at linearly distant yet three-dimensionally proximal amino acid positions appears to maintain the integrity of the glycan shield while conveying resistance to neutralisation by BCN antibodies. We find that highly conserved clusters of glycosylated residues do exist on the gp120 trimer surface and suggest that these positions may provide an exciting target for the development of BCN anticarbohydrate therapies.
Collapse
Affiliation(s)
- Simon A Travers
- Medical Research Council Unit for Bioinformatics Capacity Development, South African National Bioinformatics Institute, University of the Western Cape, Private Bag X17, Belville 7535, South Africa
| |
Collapse
|