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Hodara VL, Parodi LM, Chavez D, Smith LM, Lanford R, Giavedoni LD. Characterization of γδT cells in naïve and HIV-infected chimpanzees and their responses to T-cell activators in vitro. J Med Primatol 2014; 43:258-71. [PMID: 24660852 DOI: 10.1111/jmp.12115] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/28/2014] [Indexed: 01/21/2023]
Abstract
BACKGROUND γδT cells are effector cells that eliminate cancer and virus-infected cells. Chimpanzees are an endangered species that can naturally and experimentally be infected with SIV and HIV, respectively, but no information about the functionality of γδT cells during chronic lentiviral infection is currently available. METHODS Healthy and HIV-infected chimpanzee γδT cells were characterized by flow cytometry. γδT subsets were studied after stimulation with T-cell activators, and the release of cytokines was analyzed by Luminex assay. RESULTS γδT-cell subsets, Vδ1 and Vδ2Vγ9, showed different patterns in the expression of CD4, CD195, CD159a, and CD159c. Stimulation of γδT cells resulted in increased levels of CD4 and HLA-DR, which is more pronounced in Vδ1 T cells. Distinct cytokine patterns were found between healthy and HIV-infected chimpanzees. CONCLUSIONS Analyses of major chimpanzee γδT subsets show similarities to human γδT cells and suggest different functionality and roles in their immune response against HIV infection.
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Affiliation(s)
- Vida L Hodara
- Department of Virology & Immunology, Texas Biomedical Research Institute, San Antonio, TX, USA; Southwest National Primate Research Center, San Antonio, TX, USA
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2
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Rutjens E, Mazza S, Biassoni R, Koopman G, Ugolotti E, Fogli M, Dubbes R, Costa P, Mingari MC, Greenwood EJD, Moretta L, De Maria A, DeMaria A, Heeney JL. CD8+ NK cells are predominant in chimpanzees, characterized by high NCR expression and cytokine production, and preserved in chronic HIV-1 infection. Eur J Immunol 2010; 40:1440-50. [PMID: 20306468 DOI: 10.1002/eji.200940062] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
HIV-1 infection in humans results in an early and progressive NK cell dysfunction and an accumulation of an "anergic" CD56- CD16+ NK subset, which is characterised by low natural cytotoxicity receptor expression and low cytokine producing capacity. In contrast to humans, chimpanzee NK cells do not display a distinguishable CD56(bright) and CD56(dim) subset but, as shown here, could be subdivided into functionally different CD8+ and CD8- subsets. The CD8+ NK cells expressed significantly higher levels of triggering receptors including NKp46 and, upon in vitro activation, produced more IFN-gamma, TNF-alpha and CD107 than their CD8- counterparts. In addition, chimpanzee CD8- NK cells had relatively high levels of HLA-DR expression, suggestive of an activated state. Killing inhibitory receptors were expressed only at low levels; however, upon in vitro stimulation, they were up-regulated in CD8+ but not in CD8- NK cells and were functionally capable of inhibiting NKp30-triggered killing. In contrast to HIV-1-infected humans, infected chimpanzees maintained their dominant CD8+ NK cell population, with high expression of natural cytotoxicity receptors.
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Affiliation(s)
- Erik Rutjens
- Biomedical Primate Research Centre, Rijswijk, The Netherlands
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3
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Freissmuth D, Hiltgartner A, Stahl-Hennig C, Fuchs D, Tenner-Racz K, Racz P, Uberla K, Strasak A, Dierich MP, Stoiber H, Falkensammer B. Analysis of humoral immune responses in rhesus macaques vaccinated with attenuated SIVmac239Deltanef and challenged with pathogenic SIVmac251. J Med Primatol 2009; 39:97-111. [PMID: 20015159 DOI: 10.1111/j.1600-0684.2009.00398.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND To determine the correlation between protection and humoral immune response against simian immunodeficiency virus (SIVmac251), 11 macaques were immunized with live-attenuated SIVmac239Deltanef either intravenously or via the tonsils and exposed to SIVmac251 after either 6 or 15 months along with unvaccinated controls. RESULTS Independent of the route of vaccine application, viremia was significantly reduced in vaccinees compared with controls 2 weeks post-challenge. Concomitantly, viremia correlated inversely with SIV-specific IgG, complement-mediated lysis and neutralizing antibodies and these parameters seemed to contribute to reduced viremia. During chronic infection, six monkeys controlled viremia in the circulation (two or fewer infectious units per 10(6) PBMCs) and showed no signs of trapping in lymphatic tissues (Appendix S1). CONCLUSIONS As no significant differences were observed throughout the study, with respect to the humoral immune response and viremia control, between the two vaccinated cohorts, mucosal immunization strategies are recommended due to more simplified application.
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Affiliation(s)
- Doris Freissmuth
- Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, Innsbruck, Austria
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4
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Shedlock DJ, Silvestri G, Weiner DB. Monkeying around with HIV vaccines: using rhesus macaques to define 'gatekeepers' for clinical trials. Nat Rev Immunol 2009; 9:717-28. [PMID: 19859066 DOI: 10.1038/nri2636] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Rhesus macaques are an important animal model for the study of human disease and the development of vaccines against HIV and AIDS. HIV vaccines have been benchmarked in rhesus macaque preclinical challenge studies using chimeric viruses made up of parts of HIV and simian immunodeficiency viruses. However, the lack of efficacy in a recent clinical trial calls for a re-evaluation of the scientific assumptions regarding the predictive value of using data generated from rhesus macaques as a 'gatekeeper' for the advancement of candidate vaccines into the clinic. In this context, there is significant consensus among HIV vaccinologists that next-generation HIV vaccines must generate 'better' immunity in rhesus macaques than clinically unsuccessful vaccines generated using validated assays. Defining better immunity is the core challenge of HIV vaccine development in this system and is the focus of this Review.
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Affiliation(s)
- Devon J Shedlock
- Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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5
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An exon-based comparative variant analysis pipeline to study the scale and role of frameshift and nonsense mutation in the human-chimpanzee divergence. Comp Funct Genomics 2009:406421. [PMID: 19859573 PMCID: PMC2765723 DOI: 10.1155/2009/406421] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2009] [Revised: 07/14/2009] [Accepted: 07/18/2009] [Indexed: 11/18/2022] Open
Abstract
Chimpanzees and humans are closely related but differ in many deadly human diseases and other characteristics in physiology, anatomy, and pathology. In spite of decades of extensive research, crucial questions about the
molecular mechanisms behind the differences are yet to be understood. Here I report ExonVar, a novel computational pipeline for Exon-based human-chimpanzee comparative Variant analysis. The objective is to comparatively
analyze mutations specifically those that caused the frameshift and nonsense mutations and to assess their scale and potential impacts on human-chimpanzee divergence. Genomewide analysis of human and chimpanzee exons with ExonVar identified a number of species-specific, exon-disrupting mutations in chimpanzees but much fewer in humans. Many were found on genes involved in
important biological processes such as T cell lineage development, the pathogenesis of inflammatory diseases, and antigen induced cell death. A “less-is-more” model was previously established to illustrate the role of the gene inactivation and disruptions during human evolution. Here this analysis suggested a different model where the chimpanzee-specific exon-disrupting mutations may act as additional evolutionary force that drove the human-chimpanzee divergence. Finally, the analysis revealed a number of sequencing errors in the chimpanzee and human genome sequences and further illustrated that they could be corrected without resequencing.
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Keele BF, Jones JH, Terio KA, Estes JD, Rudicell RS, Wilson ML, Li Y, Learn GH, Beasley TM, Schumacher-Stankey J, Wroblewski E, Mosser A, Raphael J, Kamenya S, Lonsdorf EV, Travis DA, Mlengeya T, Kinsel MJ, Else JG, Silvestri G, Goodall J, Sharp PM, Shaw GM, Pusey AE, Hahn BH. Increased mortality and AIDS-like immunopathology in wild chimpanzees infected with SIVcpz. Nature 2009; 460:515-9. [PMID: 19626114 DOI: 10.1038/nature08200] [Citation(s) in RCA: 247] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2009] [Accepted: 06/05/2009] [Indexed: 12/14/2022]
Abstract
African primates are naturally infected with over 40 different simian immunodeficiency viruses (SIVs), two of which have crossed the species barrier and generated human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2). Unlike the human viruses, however, SIVs do not generally cause acquired immunodeficiency syndrome (AIDS) in their natural hosts. Here we show that SIVcpz, the immediate precursor of HIV-1, is pathogenic in free-ranging chimpanzees. By following 94 members of two habituated chimpanzee communities in Gombe National Park, Tanzania, for over 9 years, we found a 10- to 16-fold higher age-corrected death hazard for SIVcpz-infected (n = 17) compared to uninfected (n = 77) chimpanzees. We also found that SIVcpz-infected females were less likely to give birth and had a higher infant mortality rate than uninfected females. Immunohistochemistry and in situ hybridization of post-mortem spleen and lymph node samples from three infected and two uninfected chimpanzees revealed significant CD4(+) T-cell depletion in all infected individuals, with evidence of high viral replication and extensive follicular dendritic cell virus trapping in one of them. One female, who died within 3 years of acquiring SIVcpz, had histopathological findings consistent with end-stage AIDS. These results indicate that SIVcpz, like HIV-1, is associated with progressive CD4(+) T-cell loss, lymphatic tissue destruction and premature death. These findings challenge the prevailing view that all natural SIV infections are non-pathogenic and suggest that SIVcpz has a substantial negative impact on the health, reproduction and lifespan of chimpanzees in the wild.
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Affiliation(s)
- Brandon F Keele
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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7
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Stoiber H, Soederholm A, Wilflingseder D, Gusenbauer S, Hildgartner A, Dierich MP. Complement and antibodies: a dangerous liaison in HIV infection? Vaccine 2009; 26 Suppl 8:I79-85. [PMID: 19388170 DOI: 10.1016/j.vaccine.2008.11.050] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Due to ongoing recombination and mutations, HIV permanently escapes from neutralizing antibody (nAb) responses of the host. By the masking of epitopes or shedding of gp120, HIV-1 further impedes an efficient neutralization by Abs. Therefore, nAbs responses of the host are chasing behind a rapidly evolving virus and mainly non-neutralizing antibodies (non-nAbs) are present in the host. At the same time, complement deposition on immune-complexed HIV may counteract the immune response by enhancing the infection. On the other hand, complement-mediated lysis is a putative effector mechanism to control viral replication. Here we review the complex interplay between complement, neutralizing and non-neutralizing Abs during HIV infection and discuss the contribution of Abs and complement in blocking versus enhancing the course of infection.
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Affiliation(s)
- Heribert Stoiber
- Department Hygiene and Microbiology, Innsbruck Medical University, Fritz-Preglstr. 3, A-6020 Innsbruck, Austria.
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8
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Why is HIV a pathogen? Trends Microbiol 2008; 16:555-60. [DOI: 10.1016/j.tim.2008.09.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Revised: 09/24/2008] [Accepted: 09/25/2008] [Indexed: 11/19/2022]
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9
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van Grevenynghe J, Halwani R, Chomont N, Ancuta P, Peretz Y, Tanel A, Procopio FA, shi Y, Said EA, Haddad EK, Sekaly RP. Lymph node architecture collapse and consequent modulation of FOXO3a pathway on memory T- and B-cells during HIV infection. Semin Immunol 2008; 20:196-203. [PMID: 18757210 DOI: 10.1016/j.smim.2008.07.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Accepted: 07/30/2008] [Indexed: 11/16/2022]
Abstract
Lymph nodes (LNs) represent the principal site where antigen-specific memory T- and B-cell responses are primed and differentiated into memory and effector cells. During chronic viral infections such as HIV, these lymphoid tissues undergo substantial structural changes. These changes are mostly caused by an imbalanced cytokine milieu, hyper-immune activation and collagen deposition leading to fibrotic LNs. The structural integrity of the LNs is essential to prime and maintain memory responses. Because cellular signalling events both up- and down-stream of FOXO3a are critical to the generation and the maintenance of lymphocyte memory, this review will focus on the interplay between the deregulation of the immune system caused by the virus and its impact on FOXO3a.
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Affiliation(s)
- Julien van Grevenynghe
- Laboratoire d'Immunologie, Centre de Recherche, Hôpital Saint-Luc, Centre Hospitalier de l'Université de Montréal, Montréal, Québec, Canada
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10
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Rutjens E, Vermeulen J, Verstrepen B, Hofman S, Prins JM, Srivastava I, Heeney JL, Koopman G. Chimpanzee CD4+ T cells are relatively insensitive to HIV-1 envelope-mediated inhibition of CD154 up-regulation. Eur J Immunol 2008; 38:1164-72. [PMID: 18383039 DOI: 10.1002/eji.200737792] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
CD40-CD154 interaction forms a key event in regulation of crosstalk between dendritic cells and CD4 T cells. In human immunodeficiency virus (HIV)-1 infected patients CD154 expression is impaired, and the resulting loss of immune responsiveness by CD4+ T cells contributes to a progressive state of immunodeficiency in humans. Although chimpanzees are susceptible to chronic HIV-1/SIVcpz infection, they are relatively resistant to the onset of AIDS. This relative resistance is characterized by maintenance of CD4+ T cell populations and function, which is highly compromised in human patients. In our cohort of chronically HIV-1- and SIVcpz-infected chimpanzees, we demonstrated the capacity to produce IL-2, following CD3/CD28 stimulation, as well as preserved CD154 up-regulation. Cross-linking of CD4 with mAb was found to inhibit CD3/CD28-induced up-regulation of CD154 equally in chimpanzees and humans. However, specific cross-linking with trimeric recombinant HIV-1 gp140 revealed reduced sensitivity for inhibition of CD154 up-regulation in chimpanzees, requiring fourfold higher concentrations of viral protein. Chimpanzee CD4+ T cells are thus less sensitive to the immune-suppressive effect of low-dose HIV-1 envelope protein than human CD4+ T cells.
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Affiliation(s)
- Erik Rutjens
- Biomedical Primate Research Centre, Department of Virology, Rijswijk, The Netherlands
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11
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12
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Scandella E, Bolinger B, Lattmann E, Miller S, Favre S, Littman DR, Finke D, Luther SA, Junt T, Ludewig B. Restoration of lymphoid organ integrity through the interaction of lymphoid tissue-inducer cells with stroma of the T cell zone. Nat Immunol 2008; 9:667-75. [PMID: 18425132 DOI: 10.1038/ni.1605] [Citation(s) in RCA: 278] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Accepted: 02/25/2008] [Indexed: 12/11/2022]
Abstract
The generation of lymphoid microenvironments in early life depends on the interaction of lymphoid tissue-inducer cells with stromal lymphoid tissue-organizer cells. Whether this cellular interface stays operational in adult secondary lymphoid organs has remained elusive. We show here that during acute infection with lymphocytic choriomeningitis virus, antiviral cytotoxic T cells destroyed infected T cell zone stromal cells, which led to profound disruption of secondary lymphoid organ integrity. Furthermore, the ability of the host to respond to secondary antigens was lost. Restoration of the lymphoid microanatomy was dependent on the proliferative accumulation of lymphoid tissue-inducer cells in secondary lymphoid organs during the acute phase of infection and lymphotoxin alpha(1)beta(2) signaling. Thus, crosstalk between lymphoid tissue-inducer cells and stromal cells is reactivated in adults to maintain secondary lymphoid organ integrity and thereby contributes to the preservation of immunocompetence.
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Affiliation(s)
- Elke Scandella
- Research Department, Kantonal Hospital of St. Gallen, 9007 St. Gallen, Switzerland
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13
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Lane P, Kim MY, Withers D, Gaspal F, Bekiaris V, Desanti G, Khan M, McConnell F, Anderson G. Lymphoid tissue inducer cells in adaptive CD4 T cell dependent responses. Semin Immunol 2008; 20:159-63. [PMID: 18407516 DOI: 10.1016/j.smim.2008.02.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2008] [Accepted: 02/27/2008] [Indexed: 01/09/2023]
Abstract
Lymphoid tissue inducer cells (LTi) are known for their role in embryonic lymphoid tissue development. We have identified LTi in adult tissues including spleen and thymus, and provide evidence here for their presence in the submucosa of the intestine. From these observations it is clear that LTi play multiple roles in the adaptive immune system, notably the ability to recruit and sustain primed CD4 T cells in environments where they provide help to other cells. We speculate that their human equivalents could be potential targets for HIV infection and their destruction explains the pattern of loss of CD4 T cells.
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Affiliation(s)
- Peter Lane
- MRC Centre for Immune Regulation, Institute for Biomedical Research, Birmingham Medical School, Birmingham, UK.
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14
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Complement-HIV interactions during all steps of viral pathogenesis. Vaccine 2007; 26:3046-54. [PMID: 18191309 DOI: 10.1016/j.vaccine.2007.12.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Revised: 11/27/2007] [Accepted: 12/01/2007] [Indexed: 01/24/2023]
Abstract
Upon crossing the endothelial barrier of the host, HIV initiates immediate responses of the immunity system. Among its components, the complement system is one of the first the first elements, which are activated to affect HIV propagation. Complement participates not only in the early phase of the immune response, but its effects can be observed continuously and also concern the induction and modification of the adaptive immune response. Here we discuss the role of complement in early and late stages of HIV pathogenesis and review the escape mechanisms, which protect HIV from destruction by the complement system.
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15
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Rutjens E, Mazza S, Biassoni R, Koopman G, Radic L, Fogli M, Costa P, Mingari MC, Moretta L, Heeney J, De Maria A. Differential NKp30 Inducibility in Chimpanzee NK Cells and Conserved NK Cell Phenotype and Function in Long-Term HIV-1-Infected Animals. THE JOURNAL OF IMMUNOLOGY 2007; 178:1702-12. [PMID: 17237420 DOI: 10.4049/jimmunol.178.3.1702] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
HIV-1 infection in chimpanzees, the closest human relative, rarely leads to disease progression. NK cells contribute to the shaping of adaptive immune responses in humans and show perturbed phenotype and function during HIV-1 infection. In this study, we provide full phenotypic, molecular, and functional characterization for triggering molecules (NKp46, NKp30 NKp80, and NKG2D) on Pan troglodytes NK cells. We demonstrate that, in this AIDS-resistant species, relevant differences to human NK cells involve NKp80 and particularly NKp30, which is primarily involved in NK-dendritic cell interactions. Resting peripheral chimpanzee NK cells have low or absent NKp30 molecule expression due to posttranscriptional regulation and increase its levels upon in vitro activation. Following long-standing HIV-1 infection, peripheral NK cells in chimpanzees have conserved triggering receptor expression and display moderate phenotypic and functional decreases only once activated and cultured in vitro. These data suggest that one of the keys to successful lentivirus control may reside in part in a different regulation of NK cell-triggering receptor expression.
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Affiliation(s)
- Erik Rutjens
- Biomedical Primate Research Centre, Rijswijk, The Netherlands
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16
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Kim MY, McConnell FM, Gaspal FMC, White A, Glanville SH, Bekiaris V, Walker LSK, Caamano J, Jenkinson E, Anderson G, Lane PJL. Function of CD4+CD3- cells in relation to B- and T-zone stroma in spleen. Blood 2006; 109:1602-10. [PMID: 17018858 DOI: 10.1182/blood-2006-04-018465] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lymphocytes from lymphotoxin (LT) alpha-deficient mice, which lack segregation of their B- and T-cell areas, acquire normal organization following adoptive transfer into RAG-deficient recipients, identifying a non-B non-T cell in the segregation process. Here we show that a CD4+CD3- accessory cell is tightly associated with discrete VCAM-1-expressing stromal cells in B- and T-cell areas of the mouse spleen. CD4+CD3- cells express high levels of LTalpha, LTbeta, and tumor necrosis factor (TNF) alpha, which are the ligands for the LTbeta receptor and TNFR1 expressed by stromal cells. The expression of these ligands is functional, as transferring CD4+CD3- cells derived from either embryonic or adult tissues into LTalpha-deficient mice organizes B/T segregation and up-regulates CCL21 protein expression in areas where T cells are segregated from B cells. We propose that the function of CD4+CD3- cells is to form a link between primed CD4 T cells and the underlying stromal elements, creating distinct microenvironments in which they enable effector responses.
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Affiliation(s)
- Mi-Yeon Kim
- Medical Research Council, Centre for Immune Regulation, Institute for Biomedical Research, Birmingham Medical School, UK
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17
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Lane PJL, Gaspal FMC, Kim MY. Two sides of a cellular coin: CD4(+)CD3- cells regulate memory responses and lymph-node organization. Nat Rev Immunol 2005; 5:655-60. [PMID: 16034364 PMCID: PMC1351344 DOI: 10.1038/nri1665] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
We propose that CD4(+)CD3(-) cells have two functions: a well-established role in organizing lymphoid tissue during development, and a newly discovered role in supporting T-cell help for B cells both during affinity maturation in germinal centres and for memory antibody responses. As CD4(+)CD3(-) cells express the HIV co-receptors CD4 and CXC-chemokine receptor 4, we think that infection of these cells by HIV, and their subsequent destruction by the host immune system, could help to explain the loss of memory antibody responses and the destruction of lymphoid architecture that occur during disease progression to AIDS.
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Affiliation(s)
- Peter J L Lane
- Medical Research Council, Centre for Immune Regulation, Birmingham Medical School, Vincent Drive, Birmingham B15 2TT, UK.
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18
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Affiliation(s)
- Paul M Sharp
- Institute of Genetics, University of Nottingham, Queens Medical Centre, Nottingham, United Kingdom
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19
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Gueye A, Diop OM, Ploquin MJY, Kornfeld C, Faye A, Cumont MC, Hurtrel B, Barré-Sinoussi F, Müller-Trutwin MC. Viral load in tissues during the early and chronic phase of non-pathogenic SIVagm infection. J Med Primatol 2004; 33:83-97. [PMID: 15061721 DOI: 10.1111/j.1600-0684.2004.00057.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
African green monkeys (AGMs) persistently infected with SIVagm do not develop AIDS, although their plasma viremia levels can reach those reported for pathogenic HIV-1 and SIVmac infections. In contrast, the viral burden in lymph nodes in SIVagm-infected AGMs is generally lower in comparison with HIV/SIVmac pathogenic infections, at least during the chronic phase of SIVagm infection. We searched for the primary targets of viral replication, which might account for the high viremias in SIVagm-infected AGMs. We evaluated for the first time during primary infection SIVagm dissemination in various lymphoid and non-lymphoid tissues. Sixteen distinct organs at a time point corresponding to maximal virus production were analyzed for viral RNA and DNA load. At days 8 and 9 p.i., viral RNA could be detected in a wide range of tissues, such as jejunum, spleen, mesenteric lymph nodes, thymus and lung. Quantification of viral DNA and RNA as well as of productively infected cells revealed that viral replication during this early phase takes place mainly in secondary lymphoid organs and in the gut (5 x 10(4)-5 x 10(8) RNA copies/10(6) cells). By 4 years p.i., RNA copy numbers were below detection level in thymus and lung. Secondary lymphoid organs displayed 6 x 10(2)-2 x 10(6) RNA copies/10(6) cells, while some tissue fragments of ileum and jejunum still showed high viral loads (up to 10(9) copies/10(6) cells). Altogether, these results indicate a rapid dissemination of SIVagm into lymphoid tissues, including the small intestine. The latter, despite showing marked regional variations, most likely contributes significantly to the high levels of viremia observed during SIVagm infection.
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Affiliation(s)
- A Gueye
- Unité de Biologie des Rétrovirus, Institut Pasteur, Paris, France
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20
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Santiago ML, Lukasik M, Kamenya S, Li Y, Bibollet-Ruche F, Bailes E, Muller MN, Emery M, Goldenberg DA, Lwanga JS, Ayouba A, Nerrienet E, McClure HM, Heeney JL, Watts DP, Pusey AE, Collins DA, Wrangham RW, Goodall J, Brookfield JFY, Sharp PM, Shaw GM, Hahn BH. Foci of endemic simian immunodeficiency virus infection in wild-living eastern chimpanzees (Pan troglodytes schweinfurthii). J Virol 2003; 77:7545-62. [PMID: 12805455 PMCID: PMC164799 DOI: 10.1128/jvi.77.13.7545-7562.2003] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2003] [Accepted: 04/12/2003] [Indexed: 11/20/2022] Open
Abstract
Simian immunodeficiency virus of chimpanzees (SIVcpz) is the immediate precursor to human immunodeficiency virus type 1 (HIV-1), yet remarkably, the distribution and prevalence of SIVcpz in wild ape populations are unknown. Studies of SIVcpz infection rates in wild chimpanzees are complicated by the species' endangered status and by its geographic location in remote areas of sub-Saharan Africa. We have developed sensitive and specific urine and fecal tests for SIVcpz antibody and virion RNA (vRNA) detection and describe herein the first comprehensive prevalence study of SIVcpz infection in five wild Pan troglodytes schweinfurthii communities in east Africa. In Kibale National Park in Uganda, 31 (of 52) members of the Kanyawara community and 39 (of approximately 145) members of the Ngogo community were studied; none were found to be positive for SIVcpz infection. In Gombe National Park in Tanzania, 15 (of 20) members of the Mitumba community, 51 (of 55) members of the Kasekela community, and at least 10 (of approximately 20) members of the Kalande community were studied. Seven individuals were SIVcpz antibody and/or vRNA positive, and two others had indeterminate antibody results. Based on assay sensitivities and the numbers and types of specimens analyzed, we estimated the prevalence of SIVcpz infection to be 17% in Mitumba (95% confidence interval, 10 to 40%), 5% in Kasekela (95% confidence interval, 4 to 7%), and 30% in Kalande (95% confidence interval, 15 to 60%). For Gombe as a whole, the SIVcpz prevalence was estimated to be 13% (95% confidence interval, 7 to 25%). SIVcpz infection was confirmed in five chimpanzees by PCR amplification of partial pol and gp41/nef sequences which revealed a diverse group of viruses that formed a monophyletic lineage within the SIVcpzPts radiation. Although none of the 70 Kibale chimpanzees tested SIVcpz positive, we estimated the likelihood that a 10% or higher prevalence existed but went undetected because of sampling and assay limitations; this possibility was ruled out with 95% certainty. These results indicate that SIVcpz is unevenly distributed among P. t. schweinfurthii in east Africa, with foci or "hot spots" of SIVcpz endemicity in some communities and rare or absent infection in others. This situation contrasts with that for smaller monkey species, in which infection rates by related SIVs are generally much higher and more uniform among different groups and populations. The basis for the wide variability in SIVcpz infection rates in east African apes and the important question of SIVcpz prevalence in west central African chimpanzees (Pan troglodytes troglodytes) remain to be elucidated.
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Affiliation(s)
- Mario L Santiago
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama 35294, USA
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21
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Anzai T, Shiina T, Kimura N, Yanagiya K, Kohara S, Shigenari A, Yamagata T, Kulski JK, Naruse TK, Fujimori Y, Fukuzumi Y, Yamazaki M, Tashiro H, Iwamoto C, Umehara Y, Imanishi T, Meyer A, Ikeo K, Gojobori T, Bahram S, Inoko H. Comparative sequencing of human and chimpanzee MHC class I regions unveils insertions/deletions as the major path to genomic divergence. Proc Natl Acad Sci U S A 2003; 100:7708-13. [PMID: 12799463 PMCID: PMC164652 DOI: 10.1073/pnas.1230533100] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Despite their high degree of genomic similarity, reminiscent of their relatively recent separation from each other ( approximately 6 million years ago), the molecular basis of traits unique to humans vs. their closest relative, the chimpanzee, is largely unknown. This report describes a large-scale single-contig comparison between human and chimpanzee genomes via the sequence analysis of almost one-half of the immunologically critical MHC. This 1,750,601-bp stretch of DNA, which encompasses the entire class I along with the telomeric part of the MHC class III regions, corresponds to an orthologous 1,870,955 bp of the human HLA region. Sequence analysis confirms the existence of a high degree of sequence similarity between the two species. However, and importantly, this 98.6% sequence identity drops to only 86.7% taking into account the multiple insertions/deletions (indels) dispersed throughout the region. This is functionally exemplified by a large deletion of 95 kb between the virtual locations of human MICA and MICB genes, which results in a single hybrid chimpanzee MIC gene, in a segment of the MHC genetically linked to species-specific handling of several viral infections (HIV/SIV, hepatitis B and C) as well as susceptibility to various autoimmune diseases. Finally, if generalized, these data suggest that evolution may have used the mechanistically more drastic indels instead of the more subtle single-nucleotide substitutions for shaping the recently emerged primate species.
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Affiliation(s)
- Tatsuya Anzai
- Department of Genetic Information, Division of Molecular Life Science, Tokai University School of Medicine, Bohseidai, Isehara, Kanagawa 259-1193, Japan
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22
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Speth C, Stoiber H, Dierich MP. Complement in different stages of HIV infection and pathogenesis. Int Arch Allergy Immunol 2003; 130:247-57. [PMID: 12740525 DOI: 10.1159/000070211] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The complement system is one of the most important weapons of innate immunity and is involved in all infectious processes. It is not only a mechanism for direct protection against an invading pathogen but it also interacts with the adaptive immunity to optimize the pathogen-specific humoral and cellular defence cascade in the body. One of the greatest challenges for the complement system is infection by HIV with its chronic course and sequential destruction of immune cells and immune organs. Due to its dual role as direct effector and as fine tuner of adaptive immunity, we focussed on complement in this review and analysed in detail the contribution of complement to the antiviral defence and to HIV pathogenesis on the one hand and the complement evasion strategies of the virus on the other hand. In the present review, this interplay between complement and the virus is illuminated for the three different stages of HIV pathogenesis and for events during therapy: (1) the acute infection process with the early events in mucosa and serum; (2) the asymptomatic stage with the complex interplay between complement-induced lysis and viral evasion strategies; (3) the symptomatic infection and AIDS stage with progressive destruction of the lymph nodes, opportunistic infections and development of neuropathogenesis, and (4) finally, during highly active antiretroviral therapy and in vaccination approaches.
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Affiliation(s)
- Cornelia Speth
- Institute of Hygiene and Social Medicine, University of Innsbruck and Ludwig Boltzmann Institute for AIDS Research, Austria.
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23
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Ondoa P, Vereecken C, Fransen K, Colebunders R, van der Groen G, Heeney JL, Kestens L. Human and simian immunodeficiency virus-infected chimpanzees do not have increased intracellular levels of beta-chemokines in contrast to infected humans. J Med Virol 2003; 69:297-305. [PMID: 12526038 DOI: 10.1002/jmv.10289] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
This study was undertaken to explain why chimpanzees infected with HIV-1 (human immunodeficiency virus type 1) or SIV(cpz) (simian immunodeficiency virus of chimpanzee) are relatively resistant to AIDS (acquired immunodeficiency syndrome). The numbers of beta-chemokine-positive cells were compared between uninfected and infected humans and chimpanzees using three-color cytofluorometry. In humans, the percentage of beta-chemokine-positive cells was significantly higher in CD8(+) T and natural killer (NK) cells than in CD4(+) T cells in both uninfected and HIV-1-infected individuals. In the presence of HIV-1 infection, however, both CD8(+) and CD4(+) T cell subsets contained significantly more beta-chemokine-positive cells than in the absence of infection. Interestingly, in chimpanzees two important differences were noted. First, their percentage of beta-chemokine-positive CD8(+) T and NK cells was significantly higher than in uninfected humans. Second, in contrast to humans, infection with either HIV-1 or with SIV(cpz) was not associated with increased numbers of beta-chemokine-positive cells. These results indicate that: constitutive high levels of intracellular beta-chemokines in chimpanzees' CD8 lymphocytes and NK cells do not necessarily correspond to lower levels of virus replication during the chronic phase of infection; and increased percentages of beta-chemokine-positive cells in HIV-infection are not a correlate of disease resistance. The data suggest that neither pre-nor post-exposure levels of intracellular beta-chemokines are correlated with the subsequent control of disease progression.
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Affiliation(s)
- Pascale Ondoa
- Department of Microbiology, Institute of Tropical Medicine, Antwerp, Belgium
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24
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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.
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25
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Ondoa P, Vingerhoets J, Vereecken C, van der Groen G, Heeney JL, Kestens L. In vitro replication of SIVcpz is suppressed by beta-chemokines and CD8+ T cells but not by natural killer cells of infected chimpanzees. AIDS Res Hum Retroviruses 2002; 18:373-82. [PMID: 11897039 DOI: 10.1089/088922202753519151] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Unlike humans, chimpanzees are relatively resistant to AIDS after infection with HIV-1 or simian immunodeficiency virus of chimpanzee (SIVcpz). We hypothesized that resistance to disease progression is associated with efficient suppression of virus replication possibly by beta-chemokines secreted by CD8+ lymphocytes and especially natural killer (NK) cells. In vitro suppression of virus replication can be easily studied in SIVcpz-infected chimpanzees because they produce high infectious virus titers in their peripheral blood. A study was undertaken to assess the sensitivity of SIVcpz to beta-chemokines in vitro and to investigate the role of endogenous beta-chemokines in relation to the in vitro capacity of CD8+ lymphocytes and NK cells of chimpanzees to suppress SIVcpz replication. Our results show that SIVcpz uses CCR5 as a coreceptor to gain cell entry and is sensitive to recombinant beta-chemokines in vitro. Here we report that despite their potent capacity to produce RANTES, NK cells of infected chimpanzees do not suppress SIVcpz replication in vitro, in contrast to CD8+ lymphocytes. We also show that endogenous beta-chemokines are not the predominant factors mediating in vitro suppression.
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Affiliation(s)
- Pascale Ondoa
- Departments of Microbiology and Clinical Sciences, Institute of Tropical Medicine, 2000 Antwerp, Belgium
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26
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Wei Q, Fultz PN. Differential selection of specific human immunodeficiency virus type 1/JC499 variants after mucosal and parenteral inoculation of chimpanzees. J Virol 2002; 76:851-64. [PMID: 11752174 PMCID: PMC136816 DOI: 10.1128/jvi.76.2.851-864.2002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Regardless of the route of transmission, it is generally accepted that the human immunodeficiency virus type 1 (HIV-1) quasispecies transmitted from an infected individual to an uninfected individual is genetically homogeneous. This finding and the observation that HIV-1 genotypes in recipients are minor variants in the donors suggest strongly that selection for specific variants occurs. However, most analyses have been limited to the V3 region of env. In addition, the exact time at which most new infections occurred was not known, making it almost impossible to analyze virus populations present in donor-recipient pairs at the time of HIV-1 transmission. To circumvent this problem, three chimpanzees were inoculated with a genetically defined stock of cell-free HIV-1/JC499 by one of three routes: intravenously or via the cervical or penile mucosa. PCR products of the C2-to-V5 region of env were amplified from both proviral DNA and virion RNA in blood samples collected soon after infection and were screened by heteroduplex analysis (HDA). Those PCR products with distinct HDA banding patterns were cloned and sequenced. In all three animals, transmitted variants encoded one of two V3-loop populations identified in the inoculum, indicating relative homogeneity in this region. However, different virus populations, defined by combinations of specific V4 and V5 sequences, were found when variants in the animal inoculated intravenously (at least 13 V4-plus-V5 combinations) were compared with those in the two animals inoculated by the mucosal routes (limited to only four V4-plus-V5 combinations). The only V4-plus-V5 population in variants found in all three chimpanzees was the major population in the inoculum, which contained viruses with more than 30 different V4-plus-V5 combinations. That the majority of the V4-plus-V5 genotypes in variants transmitted to all three animals were minor populations in the inoculum indicated that selective transmission defined by the V4-plus-V5 regions had occurred but that distinct populations were transmitted by parenteral versus mucosal routes. These results indicate that the putative homogeneity of HIV-1 variants in a newly infected individual might be an artifact of the region of the env gene evaluated and that regions other than V3 might play a major role in selective transmission.
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Affiliation(s)
- Qing Wei
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, Alabama 35294-2170, USA
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27
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Greensill J, Sheldon JA, Murthy KK, Bessonette JS, Beer BE, Schulz TF. A chimpanzee rhadinovirus sequence related to Kaposi's sarcoma-associated herpesvirus/human herpesvirus 8: increased detection after HIV-1 infection in the absence of disease. AIDS 2000; 14:F129-35. [PMID: 11125908 DOI: 10.1097/00002030-200012010-00001] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE To look for a virus related to Kaposi's sarcoma-associated herpesvirus (KSHV) or human herpesvirus 8 (HHV8) in chimpanzees and to investigate phylogenetic and biological similarities to KSHV. METHODS Peripheral blood mononuclear cell (PBMC) DNA samples from chimpanzees (Pan troglodytes troglodytes) were screened with newly designed consensus oligonucleotide primers for the DNA polymerase gene of KSHV-related gamma2-herpesviruses (rhadinoviruses). Samples from HIV-1-infected and -uninfected chimpanzees were screened with virus-specific primers. Antibodies to KSHV structural and latent antigens were measured by immunofluorescence, enzyme-linked immunosorbent assay (ELISA) and Western blot. RESULTS We identified 972 base pairs (bp) of a new viral DNA polymerase sequence with 81.6% (nucleotides) and 93.2% (protein) identity to that of KSHV/HHV8. It was detected in 15/37 (41%) animals experimentally infected with HIV-1, but only in one out of 30 uninfected animals (P<0.001). Antibodies were found by immunofluorescence to structural, but not latent, KSHV antigens in nearly all HIV-1-infected and uninfected animals. CONCLUSION Like man and two other Old World primate species, chimpanzees harbour a virus closely related to KSHV/HHV8, termed Pan troglodytes rhadinovirus-1 (PtRV-1). Like KSHV, PtRV-1 is more easily detected by polymerase chain reaction (PCR) in the PBMC of HIV-1-infected than of HIV-1-uninfected individuals, suggesting increased viral load. Despite the close phylogenetic relationship and biological similarities between KSHV and PtRV-1, Kaposi's sarcoma (KS) has not been reported in HIV-1-infected chimpanzees. PtRV-1 may lack some of the pathogenic determinants of KSHV, or humans and chimpanzees may differ in how they control the infection with their respective rhadinoviruses.
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MESH Headings
- AIDS-Related Opportunistic Infections/complications
- AIDS-Related Opportunistic Infections/immunology
- AIDS-Related Opportunistic Infections/veterinary
- AIDS-Related Opportunistic Infections/virology
- Animals
- Antibodies, Viral/immunology
- Antigens, Viral, Tumor/immunology
- Blotting, Western
- Cells, Cultured
- Consensus Sequence/genetics
- DNA Primers
- DNA-Directed DNA Polymerase/chemistry
- DNA-Directed DNA Polymerase/genetics
- Enzyme-Linked Immunosorbent Assay
- Fluorescent Antibody Technique
- HIV Infections/complications
- HIV Infections/virology
- HIV-1/physiology
- Herpesviridae Infections/complications
- Herpesviridae Infections/immunology
- Herpesviridae Infections/veterinary
- Herpesviridae Infections/virology
- Herpesvirus 8, Human/chemistry
- Herpesvirus 8, Human/enzymology
- Herpesvirus 8, Human/genetics
- Herpesvirus 8, Human/immunology
- Humans
- Leukocytes, Mononuclear/virology
- Pan troglodytes/immunology
- Pan troglodytes/virology
- Phylogeny
- Polymerase Chain Reaction
- Rhadinovirus/chemistry
- Rhadinovirus/genetics
- Rhadinovirus/immunology
- Rhadinovirus/isolation & purification
- Viral Load
- Viral Proteins/chemistry
- Viral Proteins/genetics
- Viral Proteins/immunology
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Affiliation(s)
- J Greensill
- Department of Medical Microbiology and Genitourinary Medicine, University of Liverpool, UK
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28
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Wei Q, Javadian A, Lausen N, Fultz PN. Distribution and quantification of human immunodeficiency virus type 1, strain JC499, proviral DNA in tissues from an infected chimpanzee. Virology 2000; 276:59-69. [PMID: 11021995 DOI: 10.1006/viro.2000.0520] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Data are accumulating to show that the natural history of human immunodeficiency virus type 1 (HIV-1) in chimpanzees closely reproduces that in humans and is influenced by biologic properties of the infecting HIV-1 strain. To determine the distribution and relative amounts of HIV-1, proviral DNA in multiple tissues from a chimpanzee euthanized because of an abdominal tumor and kidney failure was quantified by nested PCR limiting-dilution assays. At death, 21 months after infection with HIV-1(JC499), this animal had a CD4(+) T-cell count of 268 and 1.7 x 10(5) copies of virion RNA/ml of plasma. The highest proviral burdens were in peripheral lymph nodes and blood, followed by lung, colon, and spleen; values ranged from 130 to 3350 proviral copies/microg DNA (equivalent to DNA in 150,000 cells). The lowest levels of virus were in the spinal cord, brain, and cecum (0.3 to 2.5 copies/microg DNA), with all other tissues harboring intermediate levels (6.8 to 114 copies/microg DNA). Viral burdens in all tissues were comparable to or greater than those reported for HIV-1-infected humans in all stages of disease. Immunohistochemistry for HIV-1 p24 Gag antigen revealed (i) trapping of HIV-1 on follicular dendritic cells in lymph node germinal centers and (ii) virus in the brain, where it was localized primarily to capillary endothelial cells in the cerebral cortex. Analysis of the genetic diversity of the Env V3 loop in tissues indicated that there was no apparent compartmentalization of HIV-1 variants. Of interest, in 83 of 94 (88.3%) clones sequenced, the unique GYGR motif at the tip of the V3 loop of HIV-1(JC499) had reverted to the more common GPGR. The results support the conclusion that HIV-1 has the potential to maintain high viral burdens in chimpanzees and to disseminate to most organs, including the central nervous system. The use of the chimpanzee model with HIV-1(JC499) (or related strains) in vaccine efficacy studies should prove valuable, especially when assessing protection against disease. Furthermore, comparison of both replicative properties of HIV-1(JC499) with SIVcpz strains and immune responses of chimpanzees infected with these viruses might provide new information about HIV pathogenesis.
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Affiliation(s)
- Q Wei
- Department of Microbiology, University of Alabama at Birmingham, BBRB 511, Birmingham, Alabama 35294-2170, USA
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29
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Beaumont T, Broersen S, van Nuenen A, Huisman HG, de Roda Husman AM, Heeney JL, Schuitemaker H. Increased neutralization sensitivity and reduced replicative capacity of human immunodeficiency virus type 1 after short-term in vivo or in vitro passage through chimpanzees. J Virol 2000; 74:7699-707. [PMID: 10933675 PMCID: PMC112298 DOI: 10.1128/jvi.74.17.7699-7707.2000] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Development of disease is extremely rare in chimpanzees when inoculated with either T-cell-line-adapted neutralization-sensitive or primary human immunodeficiency virus type 1 (HIV-1), at first excluding a role for HIV-1 neutralization sensitivity in the clinical course of infection. Interestingly, we observed that short-term in vivo and in vitro passage of primary HIV-1 isolates through chimpanzee peripheral blood mononuclear cells (PBMC) resulted in a neutralization-sensitive phenotype. Furthermore, an HIV-1 variant reisolated from a chimpanzee 10 years after experimental infection was still sensitive to neutralization by soluble CD4, the CD4 binding site recognizing antibody IgG1b12 and autologous chimpanzee serum samples, but had become relatively resistant to neutralization by polyclonal human sera and neutralizing monoclonal antibodies. The initial adaptation of HIV-1 to replicate in chimpanzee PBMC seemed to coincide with a selection for viruses with low replicative kinetics. Neither coreceptor usage nor the expression level of CD4, CCR5, or CXCR4 on chimpanzee PBMC compared to human cells could explain the phenotypic changes observed in these chimpanzee-passaged viruses. Our data suggest that the increased neutralization sensitivity of HIV-1 after replication in chimpanzee cells may in part contribute to the long-term asymptomatic HIV-1 infection in experimentally infected chimpanzees.
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Affiliation(s)
- T Beaumont
- Department of Clinical Viro-Immunology, University of Amsterdam, Academic Medical Center, Amsterdam, The Netherlands
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30
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31
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Klein E, Ho RJ. Challenges in the development of an effective HIV vaccine: current approaches and future directions. Clin Ther 2000; 22:295-314; discussion 265. [PMID: 10963285 DOI: 10.1016/s0149-2918(00)80034-x] [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: 10/18/2022]
Abstract
OBJECTIVE The intent of this review is to investigate and discuss why developing a successful HIV vaccine has been so challenging, first by examining the molecular biology of the virus and how HIV interacts with the immune system, and then reviewing past viral vaccine successes as well as future directions for HIV vaccine research. BACKGROUND Since HIV appeared in the United States in the early 1980s, an estimated 40 million people worldwide have been infected with the virus. Despite promising advances in the pharmacotherapy of HIV infection, it is apparent that the best, most cost-effective strategy for controlling the further spread of the virus is through synthesis of a protective vaccine. Almost 2 decades into the epidemic, there are few prospects for a truly effective vaccine entering the market in the foreseeable future. METHODS MEDLINE was searched for articles written between 1966 and June 1999. Search terms used were AIDS, HIV vaccine, HIV-1, HIV-2, vaccines, and human immunodeficiency virus. RESULTS Only 2 candidates for an HIV vaccine are currently in phase III clinical trials (1 in the United States and 1 in Thailand). The efficacy of these vaccines when applied to the population as a whole is widely questioned, largely because they induce protection by an antibody response only. Several studies have suggested that this approach will likely be ineffective in providing any real protection from viral infection. It appears that a strong cellular immune response is necessary in addition to a strong antibody response.
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Affiliation(s)
- E Klein
- Department of Pharmaceutics, School of Pharmacy, University of Washington, Seattle, 98195-7610, USA
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