1
|
|
2
|
Etienne L, Nerrienet E, LeBreton M, Bibila GT, Foupouapouognigni Y, Rousset D, Nana A, Djoko CF, Tamoufe U, Aghokeng AF, Mpoudi-Ngole E, Delaporte E, Peeters M, Wolfe ND, Ayouba A. Characterization of a new simian immunodeficiency virus strain in a naturally infected Pan troglodytes troglodytes chimpanzee with AIDS related symptoms. Retrovirology 2011; 8:4. [PMID: 21232091 PMCID: PMC3034674 DOI: 10.1186/1742-4690-8-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 01/13/2011] [Indexed: 12/20/2022] Open
Abstract
Background Data on the evolution of natural SIV infection in chimpanzees (SIVcpz) and on the impact of SIV on local ape populations are only available for Eastern African chimpanzee subspecies (Pan troglodytes schweinfurthii), and no data exist for Central chimpanzees (Pan troglodytes troglodytes), the natural reservoir of the ancestors of HIV-1 in humans. Here, we report a case of naturally-acquired SIVcpz infection in a P.t.troglodytes chimpanzee with clinical and biological data and analysis of viral evolution over the course of infection. Results A male chimpanzee (Cam155), 1.5 years, was seized in southern Cameroon in November 2003 and screened SIV positive during quarantine. Clinical follow-up and biological analyses have been performed for 7 years and showed a significant decline of CD4 counts (1,380 cells/mm3 in 2004 vs 287 in 2009), a severe thrombocytopenia (130,000 cells/mm3 in 2004 vs 5,000 cells/mm3 in 2009), a weight loss of 21.8% from August 2009 to January 2010 (16 to 12.5 kg) and frequent periods of infections with diverse pathogens. DNA from PBMC, leftover from clinical follow-up samples collected in 2004 and 2009, was used to amplify overlapping fragments and sequence two full-length SIVcpzPtt-Cam155 genomes. SIVcpzPtt-Cam155 was phylogenetically related to other SIVcpzPtt from Cameroon (SIVcpzPtt-Cam13) and Gabon (SIVcpzPtt-Gab1). Ten molecular clones 5 years apart, spanning the V1V4 gp120 env region (1,100 bp), were obtained. Analyses of the env region showed positive selection (dN-dS >0), intra-host length variation and extensive amino acid diversity between clones, greater in 2009. Over 5 years, N-glycosylation site frequency significantly increased (p < 0.0001). Conclusions Here, we describe for the first time the clinical history and viral evolution of a naturally SIV infected P.t.troglodytes chimpanzee. The findings show an increasing viral diversity over time and suggest clinical progression to an AIDS-like disease, showing that SIVcpz can be pathogenic in its host, as previously described in P.t.schweinfurthii. Although studying the impact of SIV infection in wild apes is difficult, efforts should be made to better characterize the pathogenicity of the ancestors of HIV-1 in their natural host and to find out whether SIV infection also plays a role in ape population decline.
Collapse
Affiliation(s)
- Lucie Etienne
- UMR145, Institut de Recherche pour le Développement (IRD) and Université Montpellier 1, Montpellier, France
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Dieltjens T, Heyndrickx L, Willems B, Gray E, Van Nieuwenhove L, Grupping K, Vanham G, Janssens W. Evolution of antibody landscape and viral envelope escape in an HIV-1 CRF02_AG infected patient with 4E10-like antibodies. Retrovirology 2009; 6:113. [PMID: 20003438 PMCID: PMC2801487 DOI: 10.1186/1742-4690-6-113] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2009] [Accepted: 12/14/2009] [Indexed: 12/17/2022] Open
Abstract
Background A minority of HIV-1 infected individuals develop broad cross-neutralizing (BCN) plasma antibodies that are capable of neutralizing a spectrum of virus variants belonging to different HIV-1 clades. The aim of this study was to identify the targeted epitopes of an individual with BCN plasma antibodies, referred to as ITM4, using peptide phage display. This study also aimed to use the selected mimotopes as tools to unravel the evolution of the antibody landscape and the viral envelope escape which may provide us with new insights for vaccine design. Results This study led us to identify ITM4 plasma antibodies directed to the 4E10 epitope located in the gp41 membrane-proximal external region (MPER). Analysis of antibody specificities revealed unusual immunogenic properties of the ITM4 viral envelope, as not only the V3 loop and the gp41 MPER but also the C1 and lentivirus lytic peptide 2 (LLP2) region seem to be targets of the immune system. The 4E10-like antibodies are consistently elicited during the 6-year follow up period. HIV-1 ITM4 pseudoviruses showed an increasing resistance over time to MPER monoclonal antibodies 4E10 and 2F5, although no changes are found in the critical positions of the epitope. Neutralization of COT6.15 (subtype C; 4E10-sensitive) pseudoviruses with alanine substitutions in the MPER region indicated an overlapping specificity of the 4E10 monoclonal antibody and the ITM4 follow up plasma. Moreover the 4E10-like antibodies of ITM4 contribute to the BCN capacity of the plasma. Conclusions Using ITM4 BCN plasma and peptide phage display technology, we have identified a patient with 4E10-like BCN antibodies. Our results indicate that the elicited 4E10-like antibodies play a role in virus neutralization. The viral RNA was isolated at different time points and the ITM4 envelope sequence analysis of both early (4E10-sensitive) and late (4E10-resistant) viruses suggest that other regions in the envelope, outside the MPER region, contribute to the accessibility and sensitivity of the 4E10 epitope. Including ITM4 specific HIV-1 Env properties in vaccine strategies may be a promising approach.
Collapse
Affiliation(s)
- Tessa Dieltjens
- Department of Microbiology, Unit of Virology, Institute of Tropical Medicine, Antwerp, Belgium.
| | | | | | | | | | | | | | | |
Collapse
|
4
|
Nyambi P, Burda S, Urbanski M, Heyndrickx L, Janssens W, Vanham G, Nadas A. Neutralization patterns and evolution of sequential HIV type 1 envelope sequences in HIV type 1 subtype B-infected drug-naive individuals. AIDS Res Hum Retroviruses 2008; 24:1507-19. [PMID: 19018670 DOI: 10.1089/aid.2008.0154] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To design a vaccine that will remain potent against HIV-1, the immunogenic regions in the viral envelope that tend to change as well as those that remain constant over time must be identified. To determine the neutralization profiles of sequential viruses over time and study whether neutralization patterns correlate with sequence evolution, 12 broadly neutralizing plasmas from HIV-1 subtype B-infected individuals were tested for their ability to neutralize sequential primary HIV-1 subtype B viruses from four individuals. Three patterns of neutralization were observed, including a loss of neutralization sensitivity by viruses over time, an increase in neutralization sensitivity by sequential viruses, or a similarity in the sensitivity of sequential viruses to neutralization. Seven to 11 gp160 clones from each sequential virus sample were sequenced and analyzed to identify mutational patterns. Analysis of the envelope sequences of the sequential viruses revealed changes characteristic of the neutralization patterns. Viruses that evolved to become resistant to neutralizing antibodies also evolved with diverse sequences, with most of the changes being due to nonsynonymous mutations occurring in the V1/V2, as well as in the constant regions (C2, C3, C4), the most changes occurring in the C3. Viruses from the patient that evolved to become more sensitive to neutralization exhibited less sequence diversity with fewer nonsynonymous changes that occurred mainly in the V1/V2 region. The V3 region remained constant over time for all the viruses tested. This study demonstrates that as viruses evolve in their host, they either become sensitive or resistant to neutralization by antibodies in heterologous plasma and mutations in different envelope regions account for these changes in their neutralization profiles.
Collapse
Affiliation(s)
- Phillipe Nyambi
- Department of Pathology, New York University School of Medicine, New York, New York 10016
- Research Enhancement Award Program, Veterans Affairs New York Harbor Healthcare System, New York, New York 10010
| | - Sherri Burda
- Department of Pathology, New York University School of Medicine, New York, New York 10016
| | - Mateusz Urbanski
- Department of Pathology, New York University School of Medicine, New York, New York 10016
| | - Leo Heyndrickx
- Virology Unit, Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium
| | - Wouter Janssens
- Virology Unit, Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium
| | - Guido Vanham
- Virology Unit, Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium
- Department of Biomedical Sciences, Faculty of Pharmaceutical, Veterinary and Biomedical Sciences, University of Antwerp, Antwerp, Belgium
| | - Arthur Nadas
- Institute of Environmental Medicine, New York University School of Medicine, New York, New York 10016
| |
Collapse
|
5
|
Münk C, Zielonka J, Constabel H, Kloke BP, Rengstl B, Battenberg M, Bonci F, Pistello M, Löchelt M, Cichutek K. Multiple restrictions of human immunodeficiency virus type 1 in feline cells. J Virol 2007; 81:7048-60. [PMID: 17459941 PMCID: PMC1933292 DOI: 10.1128/jvi.02714-06] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The productive replication of human immunodeficiency virus type 1 (HIV-1) occurs exclusively in defined cells of human or chimpanzee origin, explaining why heterologous animal models for HIV replication, pathogenesis, vaccination, and therapy are not available. This lack of an animal model for HIV-1 studies prompted us to examine the susceptibility of feline cells in order to evaluate the cat (Felis catus) as an animal model for studying HIV-1. Here, we report that feline cell lines harbor multiple restrictions with respect to HIV-1 replication. The feline CD4 receptor does not permit virus infection. Feline T-cell lines MYA-1 and FeT-1C showed postentry restrictions resulting in low HIV-1 luciferase reporter activity and low expression of viral Gag-Pol proteins when pseudotyped vectors were used. Feline fibroblastic CrFK and KE-R cells, expressing human CD4 and CCR5, were very permissive for viral entry and HIV-long terminal repeat-driven expression but failed to support spreading infection. KE-R cells displayed a profound block with respect to release of HIV-1 particles. In contrast, CrFK cells allowed very efficient particle production; however, the CrFK cell-derived HIV-1 particles had low specific infectivity. We subsequently identified feline apolipoprotein B-editing catalytic polypeptide 3 (feAPOBEC3) proteins as active inhibitors of HIV-1 particle infectivity. CrFK cells express at least three different APOBEC3s: APOBEC3C, APOBEC3H, and APOBEC3CH. While the feAPOBEC3C did not significantly inhibit HIV-1, the feAPOBEC3H and feAPOBEC3CH induced G to A hypermutations of the viral cDNA and reduced the infectivity approximately 10- to approximately 40-fold.
Collapse
Affiliation(s)
- Carsten Münk
- Division of Medical Biotechnology, Paul-Ehrlich-Institut, Paul-Ehrlich-Str. 51-59, 63225 Langen, Germany.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
|
7
|
Verity EE, Williams LA, Haddad DN, Choy V, O'Loughlin C, Chatfield C, Saksena NK, Cunningham A, Gelder F, McPhee DA. Broad neutralization and complement-mediated lysis of HIV-1 by PEHRG214, a novel caprine anti-HIV-1 polyclonal antibody. AIDS 2006; 20:505-15. [PMID: 16470114 DOI: 10.1097/01.aids.0000210604.78385.95] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
OBJECTIVES To assess the potency, breadth of action, and mechanism of action of the polyclonal goat anti-HIV antibody, PEHRG214. DESIGN Typical human antibody responses to HIV-1 infection are unable to neutralize virus efficiently, clear the infection, or prevent disease progression. However, more potent neutralizing antibodies may be capable of playing a pivotal role in controlling HIV replication in vivo. PEHRG214 is a polyclonal caprine antibody raised against purified HIV-associated proteins, such that epitopes that are immunologically silent in humans may potentially be recognized in another species. It has been administered safely to HIV-infected individuals in Phase I clinical trials. METHODS The anti-HIV activity of PEHRG214 was assessed using neutralization and virion lysis assays. The target proteins for PEHRG214 activity were investigated using flow cytometry and by adsorption of anti-cell antibodies from the antibody cocktail. RESULTS PEHRG214 strongly neutralized a diverse range of primary HIV-1 isolates, encompassing subtypes A to E and both CCR5 and CXCR4 phenotypes. Neutralization was enhanced by the presence of complement. PEHRG214 also induced complement-mediated lysis of all HIV-1 isolates tested, and recognized or cross-reacted with a number of host cell proteins. Lysis was abrogated by adsorption with T and/or B cells expressing GPI-linked proteins, but not by GPI-deficient B cells or red blood cells. CONCLUSIONS PEHRG214 was found to potently neutralize and lyse HIV-1 particles. By targeting host cell proteins present in the viral envelope, which are conserved among all strains tested, PEHRG214 potentially opens up a highly novel means of eliminating circulating virus in infected individuals.
Collapse
Affiliation(s)
- Erin E Verity
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Ouverney EP, Teixeira SLM, Silva-de-Jesus C, Hacker MA, Morgado MG, Bastos FI, Bongertz V. HIV-1 binding and neutralizing antibodies of injecting drug users. Braz J Med Biol Res 2005; 38:1313-20. [PMID: 16138213 DOI: 10.1590/s0100-879x2005000900004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Previous studies have demonstrated a stronger seroreactivity against some synthetic peptides responsible for inducing neutralizing antibodies in injecting drug users (IDU) compared to that of individuals sexually infected with HIV-1 (S), but the effectiveness in terms of the neutralizing ability of these antibodies has not been evaluated. Our objective was to study the humoral immune response of IDU by determining the specificity of their antibodies and the presence of neutralizing antibodies. The neutralization capacity against the HIV-1 isolate MN (genotype B), the primary HIV-1 isolate 95BRRJ021 (genotype F), and the seroreactivity with peptides known to induce neutralizing antibodies, from the V2 and V3 loops of different HIV-1 subtypes, were analyzed. Seroreactivity indicates that IDU plasma are more likely to recognize a broader range of peptides than S plasma, with significantly higher titers, especially of V3 peptides. Similar neutralization frequencies of the MN isolate were observed in plasma of the IDU (16/47) and S (20/60) groups in the 1:10 dilution. The neutralization of the 95BRRJ021 isolate was more frequently observed for plasma from the S group (15/23) than from the IDU group (15/47, P = 0.0108). No correlation between neutralization and seroreactivity with the peptides tested was observed. These results suggest that an important factor responsible for the extensive and broad humoral immune response observed in IDU is their infection route. There was very little difference in neutralizing antibody response between the IDU and S groups despite their differences in seroreactivity and health status.
Collapse
Affiliation(s)
- E P Ouverney
- Departamento de Imunologia, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil.
| | | | | | | | | | | | | |
Collapse
|
9
|
Affiliation(s)
- Paul M Sharp
- Institute of Genetics, University of Nottingham, Queens Medical Centre, Nottingham, United Kingdom
| | | | | |
Collapse
|
10
|
Nádas A, Zhong P, Burda S, Zekeng L, Urbanski M, Gorny MK, Zolla-Pazner S, Nyambi PN. Defining human immunodeficiency virus (HIV) type 1 immunotypes with six human monoclonal antibodies. AIDS Res Hum Retroviruses 2004; 20:55-65. [PMID: 15000699 DOI: 10.1089/088922204322749503] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Studies of HIV-1 immunological relatedness have revealed that genetic diversity does not parallel antigenic diversity and have recently shown that HIV-1 strains from different geographic regions from around the world can be grouped into a small number of immunologically defined groups (immunotypes). Previously, the binding patterns of 28 monoclonal antibodies (mAbs) (specific for V3 and C5 of gp120 and cluster I of gp41) with 26 HIV-1 virions obtained globally were determined in a virus binding assay. Analysis of the binding patterns of these 728 mAb/virus combinations now reveals that a particular subset containing six of the 28 mAbs can correctly immunotype 24 of the 26 isolates (92%) into three immunotypes. Like the original panel of mAbs, the subset of six mAbs identified was directed against epitopes in the V3 and C5 regions of gp 120 as well as cluster I of gp41. The binding patterns ("profiles") of these six mAbs with 24 additional HIV-1 virions from Cameroon confirmed that epitopes in V3 and C5 of gp120 and cluster I of gp41 are well exposed on these viruses. Multivariate analysis of the binding patterns of these six mAbs with all 50 viruses (26 obtained globally and 24 obtained from Cameroon) indicates that the viruses from Cameroon have binding profiles similar to viruses from the rest of the world and can be classified into the same three immunotypes that were previously described. This study suggests that a vaccine against HIV-1 need not be based on geographic origin of the virus or on clade, but may better be based on antigenic properties that classify the plethora of different HIV-1 viruses into immunologically defined groups.
Collapse
Affiliation(s)
- Arthur Nádas
- Institute of Environmental Medicine, New York University School of Medicine, New York, New York 10016, USA
| | | | | | | | | | | | | | | |
Collapse
|
11
|
Ondoa P, Davis D, Kestens L, Vereecken C, Garcìa Ribas S, Fransen K, Heeney J, van der Groen G. In vitro susceptibility to infection with SIVcpz and HIV-1 is lower in chimpanzee than in human peripheral blood mononuclear cells. J Med Virol 2002; 67:301-11. [PMID: 12116019 DOI: 10.1002/jmv.10078] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This study was undertaken to evaluate and compare the susceptibility of chimpanzee versus human peripheral blood mononuclear cells (PBMCs) to infection with SIVcpz and HIV-1 non-syncitium inducing primary isolates. The results demonstrate clearly that chimpanzee PBMCs have a lower capacity to support viral replication as compared to human PBMCs. There was no experimental evidence that this difference was due to a lower availability of target cells for viral infection (PBMCs positive for CD4 and CCR5 molecules) or to a differential susceptibility to apoptosis (PBMCs positive for CD4 and CD95 molecules). A lower capacity of chimpanzee PBMCs to support SIVcpz and HIV-1 replication in vitro is related to a post-entry barrier to virus replication.
Collapse
|
12
|
Ondoa P, Davis D, Willems B, Heyndrickx L, Kestens L, van der Berg I, Coppens S, Janssens W, Heeney J, van der Groen G. Genetic variability of the V1 and V2 env domains of SIVcpz-ant and neutralization pattern of plasma viruses in a chimpanzee infected naturally. J Med Virol 2001; 65:765-76. [PMID: 11745943 DOI: 10.1002/jmv.2102] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Specific neutralizing epitope changes have been observed in a chimpanzee infected naturally with SIVcpz, which differ from HIV-1 infecting humans. To characterize further these changes, a longitudinal study of env genomic sequence variation of SIVcpz-ant isolates was undertaken in this animal. The V1 and V2 regions of the env were determined to arise from specific recombination events. To determine whether recombination of the V1 and V2 domains was possibly associated with the emergence of neutralization escape viruses, envelope sequences and gene length polymorphisms from PBMC and plasma viral variants were studied over a 7-year period. PBMCs and plasma-associated infectious virus titers as well as plasma RNA viral loads were monitored longitudinally. The first 5 viruses isolated from the plasma were found to be neutralization escape variants. Sequence analysis of their V1 and the V2 regions indicated that a 20 amino acid stretch of the V1 region had undergone recombination and was also associated with the emergence of isolates eliciting strong neutralization responses. These findings support the hypothesis that recombination of the V1 and V2 regions of the envelope play a role in neutralization escape of SIVcpz in chimpanzees infected naturally. Furthermore, the data confirm that the neutralizing antibody response plays an important role in the decline of plasma infectious virus titers in HIV-1 related SIVcpz nonpathogenic infection.
Collapse
Affiliation(s)
- P Ondoa
- Institute of Tropical Medicine, Antwerp, Belgium
| | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
McGrath KM, Hoffman NG, Resch W, Nelson JA, Swanstrom R. Using HIV-1 sequence variability to explore virus biology. Virus Res 2001; 76:137-60. [PMID: 11410314 DOI: 10.1016/s0168-1702(01)00271-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) only recently established an epidemic world-wide infection in the human population. The virus persists in the human host through active replication and is able to avoid clearance by the immune system. Active replication is an important component of the rapid evolutionary potential of HIV-1, a potential which manifests itself in the evolution of immune escape variants, drug resistant variants, and variants with the ability to use different cell surface coreceptors in conjunction with CD4. Multiple zoonotic introductions, compartmentalization of virus replication in the body, and genetic bottlenecks associated with sampling during transmission, antiretroviral therapy, and geographic and/or host population isolation further contribute to the range of sequences present in extant viruses. The sum of the history of all of these phenomena is reflected in HIV-1 sequence variability, and most of these phenomena are ongoing today. Here we review the use of HIV-1 sequence variability to explore its underlying biology.
Collapse
Affiliation(s)
- K M McGrath
- UNC Center for AIDS Research, University of North Carolina at Chapel Hill, 22-062 Lineberger Cancer Center, CB# 7295, Chapel Hill, NC 27599-7295, USA
| | | | | | | | | |
Collapse
|
14
|
Zwick MB, Bonnycastle LL, Menendez A, Irving MB, Barbas CF, Parren PW, Burton DR, Scott JK. Identification and characterization of a peptide that specifically binds the human, broadly neutralizing anti-human immunodeficiency virus type 1 antibody b12. J Virol 2001; 75:6692-9. [PMID: 11413337 PMCID: PMC114393 DOI: 10.1128/jvi.75.14.6692-6699.2001] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Human monoclonal antibody (MAb) b12 recognizes a conformational epitope that overlaps the CD-4-binding site of the human immunodeficiency virus type 1 (HIV-1) envelope. MAb b12 neutralizes a broad range of HIV-1 primary isolates and protects against primary virus challenge in animal models. We report here the discovery and characterization of B2.1, a peptide that binds specifically to MAb b12. B2.1 was selected from a phage-displayed peptide library by using immunoglobulin G1 b12 as the selecting agent. The peptide is a homodimer whose activity depends on an intact disulfide bridge joining its polypeptide chains. Competition studies with gp120 indicate that B2.1 occupies the b12 antigen-binding site. The affinity of b12 for B2.1 depends on the form in which the peptide is presented; b12 binds best to the homodimer as a recombinant polypeptide fused to the phage coat. Originally, b12 was isolated from a phage-displayed Fab library constructed from the bone marrow of an HIV-1-infected donor. The B2.1 peptide is highly specific for b12 since it selected only phage bearing b12 Fab from this large and diverse antibody library.
Collapse
Affiliation(s)
- M B Zwick
- Department of Molecular Biology and Biochemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia V5A 1S6, Canada
| | | | | | | | | | | | | | | |
Collapse
|
15
|
Nyambi PN, Nádas A, Mbah HA, Burda S, Williams C, Gorny MK, Zolla-Pazner S. Immunoreactivity of intact virions of human immunodeficiency virus type 1 (HIV-1) reveals the existence of fewer HIV-1 immunotypes than genotypes. J Virol 2000; 74:10670-80. [PMID: 11044111 PMCID: PMC110941 DOI: 10.1128/jvi.74.22.10670-10680.2000] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
In order to protect against organisms that exhibit significant genetic variation, polyvalent vaccines are needed. Given the extreme variability of human immunodeficiency virus type 1 (HIV-1), it is probable that a polyvalent vaccine will also be needed for protection from this virus. However, to understand how to construct a polyvalent vaccine, serotypes or immunotypes of HIV must be identified. In the present study, we have examined the immunologic relatedness of intact, native HIV-1 primary isolates of group M, clades A to H, with human monoclonal antibodies (MAbs) directed at epitopes in the V3, C5, and gp41 cluster I regions of the envelope glycoproteins, since these regions are well exposed on the virion surface. Multivariate analysis of the binding data revealed three immunotypes of HIV-1 and five MAb groups useful for immunotyping of the viruses. The analysis revealed that there are fewer immunotypes than genotypes of HIV and that clustering of the isolates did not correlate with either genotypes, coreceptor usage (CCR5 and CXCR4), or geographic origin of the isolates. Further analysis revealed distinct MAb groups that bound preferentially to HIV-1 isolates belonging to particular immunotypes or that bound to all three immunotypes; this demonstrates that viral immunotypes identified by mathematical analysis are indeed defined by their immunologic characteristics. In summary, these results indicate (i) that HIV-1 immunotypes can be defined, (ii) that constellations of epitopes that are conserved among isolates belonging to each individual HIV-1 immunotype exist and that these distinguish each of the immunotypes, and (iii) that there are also epitopes that are routinely shared by all immunotypes.
Collapse
Affiliation(s)
- P N Nyambi
- Department of Pathology, New York University School of Medicine, New York, New York 10016, USA
| | | | | | | | | | | | | |
Collapse
|
16
|
Beirnaert E, Nyambi P, Willems B, Heyndrickx L, Colebunders R, Janssens W, van der Groen G. Identification and characterization of sera from HIV-infected individuals with broad cross-neutralizing activity against group M (env clade A-H) and group O primary HIV-1 isolates. J Med Virol 2000. [DOI: 10.1002/1096-9071(200009)62:1%3c14::aid-jmv3%3e3.0.co;2-l] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
|
17
|
Burton DR, Parren PW. Vaccines and the induction of functional antibodies: time to look beyond the molecules of natural infection? Nat Med 2000; 6:123-5. [PMID: 10655088 DOI: 10.1038/72200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Infection with some pathogens induces weak functional antibody responses that are non-protective, and there has been some skepticism about a role for antibodies in vaccine design. However, newer data show that antibodies can protect against infection with these pathogens, and new methods to elicit production of functional antibodies should be sought.
Collapse
Affiliation(s)
- D R Burton
- Department of Immunology and Molecular Biology, The Scripps Research Institute, La Jolla, California 92037, USA.
| | | |
Collapse
|
18
|
Beirnaert E, Nyambi P, Willems B, Heyndrickx L, Colebunders R, Janssens W, van der Groen G. Identification and characterization of sera from HIV-infected individuals with broad cross-neutralizing activity against group M (env clade A-H) and group O primary HIV-1 isolates. J Med Virol 2000. [DOI: 10.1002/1096-9071(200009)62:1<14::aid-jmv3>3.0.co;2-l] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
19
|
Nkengasong JN, Willems B, Janssens W, Cheingsong-Popov R, Heyndrickx L, Barin F, Ondoa P, Fransen K, Goudsmit J, van der Groen G. Lack of correlation between V3-loop peptide enzyme immunoassay serologic subtyping and genetic sequencing. AIDS 1998; 12:1405-12. [PMID: 9727560 DOI: 10.1097/00002030-199812000-00001] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
OBJECTIVE To compare the performance of V3-loop peptide enzyme immunoassay (PEIA) methodologies from four different laboratories for subtyping HIV-1, and to determine the causes for the lack of correlation between V3-loop PEIA serotyping and subtyping by sequencing. MATERIALS AND METHODS Synthetic peptides derived from the amino-acid consensus sequences of the V3-loop of group M strains representing genetic subtypes A-F as well as reference strains were evaluated in PEIA by four different laboratories for their ability to accurately determine the subtype in a panel of 85 sera obtained from persons infected with known HIV-1 subtypes (28 subtype A, 34 subtype B, four subtype C, 10 subtype D, seven subtype F, one each of subtype H and G). Furthermore, the V3 loop of the corresponding virus was compared with the V3 loop of the peptides used in PEIA. RESULTS The correlation between HIV-1 subtyping by sequencing and V3-loop PEIA from the different laboratories varied considerably for the different HIV-1 subtypes: subtype A (46-68%), B (38-85%), C (75-100%), D (29-50%), and F (17-57%). A 70% agreement between PEIA and sequencing subtypes was observed for samples with the concordant presence of the same octameric sequences in the V3 loop of the virus and the V3 loop of the peptide used in PEIA; however, only 42% of specimens with different V3-loop octameric viral and peptide sequences yielded concordant results in V3-loop serotyping and genetic subtyping. CONCLUSION Our results indicate that V3-loop PEIA methodologies used in different laboratories correlate poorly with genetic subtyping, and that their accuracy to predict HIV-1 subtypes in sera of Belgian individuals infected with different HIV-1 subtypes (A, B, C, D, F, G and H) vary considerably. The poor correlation between serotyping and genetic subtyping was partly due to the simultaneous occurrence of subtype-specific octameric sequences at the tip of the V3 loop of viruses belonging to different genetic subtypes.
Collapse
Affiliation(s)
- J N Nkengasong
- Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Quinnan GV, Zhang PF, Fu DW, Dong M, Margolick JB. Evolution of neutralizing antibody response against HIV type 1 virions and pseudovirions in multicenter AIDS cohort study participants. AIDS Res Hum Retroviruses 1998; 14:939-49. [PMID: 9686640 DOI: 10.1089/aid.1998.14.939] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Changes in neutralizing antibody (NA) titers in stored sera collected over 5 years from 10 participants in the Multicenter AIDS Cohort Study (MACS) were evaluated. The participants were HIV-1 infected on enrollment in the MACS, and remained AIDS free during the 5-year study interval. Seven viruses derived from molecular clones were used in NA assays; five of the viruses were T tropic (NL4-3, ALA1, NY5, SF2, and Z2Z6) and two were M tropic [AD8 and NL(SF162)]. In addition, pseudoviruses (PVs) were constructed that expressed envelope genes from NL4-3, ALA1, AD8, and SF162 and from primary viruses from two MACS participants (PV-9 and PV-10). There was significant correlation between NA titers obtained in four of five virus/PV comparisons, while the SF162 PV was more sensitive to NA than the corresponding virus. Comparable changes in NA titers were detected using viruses and PVs. Fourfold or greater increases in NA titers were noted in each of the participants, involving recognition of one to five of the nine strains tested. In some patients these NA titer changes appeared as discrete episodes of immune responses, while in others there may have been either multiple episodes or continuous evolution of the NA responses. The data indicate that changes in NA specificity occur during HIV-1 infection, which may result from the occurrence of neutralization escape mutation. The use of PVs for the study of phenotypic characteristics of envelope glycoproteins should facilitate the study of neutralization escape mutation in HIV-1 infection.
Collapse
Affiliation(s)
- G V Quinnan
- Department of Preventive Medicine and Biometrics, Uniformed Services University of the Health Sciences, Bethesda, Maryland 20814, USA
| | | | | | | | | |
Collapse
|
21
|
Daeyaert F, Moereels H, Lewi PJ. Classification and identification of proteins by means of common and specific amino acid n-tuples in unaligned sequences. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 1998; 56:221-233. [PMID: 9725648 DOI: 10.1016/s0169-2607(98)00031-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Unaligned amino acid sequences can be characterized by their composition of amino acid n-tuples (i.e. doublets, triplets, quadruplets, etc.). In this study we investigated the performance of two statistics, termed commonality and specificity, that are derived from n-tuple counts using a set of G-protein coupled receptor (GPCR) sequences. The commonality of a tuple is defined as its relative occurrence in the sequences that belong to a given GPCR subtype. The specificity of a tuple is derived from its relative occurrence in the sequences of a given GPCR subtype and from its relative non-occurrence in the sequences that do not belong to this subtype. A graphical presentation, termed 'polygram', is described for the visualization of common and specific tuples. The method can be applied to the classification of unknown GPCR sequences. It can also be applied to the identification of fragments of GPCRs, such as may occur in chimeric receptors. The method is generally applicable to other protein families and other types of coding.
Collapse
Affiliation(s)
- F Daeyaert
- Center for Molecular Design, Janssen Research Foundation, Vosselaar, Belgium
| | | | | |
Collapse
|