Simian Immunodeficiency Virus Infection of Chimpanzees (Pan troglodytes) Shares Features of Both Pathogenic and Non-pathogenic Lentiviral Infections.

The virus-host relationship in simian immunodeficiency virus (SIV) infected chimpanzees is thought to be different from that found in other SIV infected African primates. However, studies of captive SIVcpz infected chimpanzees are limited. Previously, the natural SIVcpz infection of one chimpanzee, and the experimental infection of six chimpanzees was reported, with limited follow-up. Here, we present a long-term study of these seven animals, with a retrospective re-examination of the early stages of infection. The only clinical signs consistent with AIDS or AIDS associated disease was thrombocytopenia in two cases, associated with the development of anti-platelet antibodies. However, compared to uninfected and HIV-1 infected animals, SIVcpz infected animals had significantly lower levels of peripheral blood CD4+ T-cells. Despite this, levels of T-cell activation in chronic infection were not significantly elevated. In addition, while plasma levels of β2 microglobulin, neopterin and soluble TNF-related apoptosis inducing ligand (sTRAIL) were elevated in acute infection, these markers returned to near-normal levels in chronic infection, reminiscent of immune activation patterns in 'natural host' species. Furthermore, plasma soluble CD14 was not elevated in chronic infection. However, examination of the secondary lymphoid environment revealed persistent changes to the lymphoid structure, including follicular hyperplasia in SIVcpz infected animals. In addition, both SIV and HIV-1 infected chimpanzees showed increased levels of deposition of collagen and increased levels of Mx1 expression in the T-cell zones of the lymph node. The outcome of SIVcpz infection of captive chimpanzees therefore shares features of both non-pathogenic and pathogenic lentivirus infections.This work was supported by the Biotechnology and Biological Sciences Research Council and by the Wellcome Trust.This is the final version of the article. It first appeared from PLOS via http://dx.doi.org/10.1371/journal.ppat.100514

HIV infection leads to differential expression of T-cell receptor V-beta genes in CD4+ and CD8+ T cells

Objective: To analyse variation in T-cell receptor (TCR) Vbeta gene expression in T cells in HIV-infected individuals. Design: Because there are very few monoclonal antibodies available for studying TCR Vbeta gene expression, we used polymerase chain reaction (PCR) to analyse the TCR Vbeta repertoire in HIV-infected individuals using specific primers for 20 distinct families of TCR Vbeta. Methods: Evaluation of TCR Vbeta gene expression in peripheral blood from HIV-1-infected individuals [two in Centers for Disease Control (CDC) stage II, five in CDC stage III and four in CDC stage IV]. Complementary DNA was produced from CD4+ and CD8+ T cells, amplified by PCR and analysed after Southern blotting and hybridization with a Cbeta-specific oligonucleotide probe. Results: Vbeta gene expression was dramatically modified, especially in AIDS patients. The CD4+ T-cell subset showed both overexpression (Vbeta2) and deletions or underexpression (Vbeta9-Vbeta20), whereas these gene segments were expressed normally in the CD8+ subset. Only Vbeta 3 was deleted or underexpression in both CD4+ and CD8+ populations in AIDS patients. Conclusions: HIV-1 infection induces CD4+ T-cell deficiency, both in total numbers and by causing a paucity of select Vbeta gene expression in this subset. In addition, the Vbeta3 gene family was deleted or underexpressed was observed in both CD4+ and CD8+ T-cell subsets from patients in CDC stage IV. These results are compatible with changes in Vbeta gene expression known to occur under the action of endogenous or exogenous superantigens

West Nile and St. Louis Encephalitis Viruses Antibodies Surveillance in Captive and Free-Ranging Birds of Prey from Argentina

We evaluated the prevalence of WNV and SLEV neutralizing antibodies in captive and free-ranging raptors from Argentina by plaque-reduction neutralization test. Eighty plasma samples from 12 species were analyzed. Only one captive adult Crowned Eagle (Harpyhaliaetus coronatus) was WNV seropositive (prevalence: 1.25%; antibody titer of 1:80). Two captive Crowned Eagles were SLEV seropositive (prevalence: 2.50%; antibody titers: 1:80 and 1:40).These findings expand the geographic distribution of WNV and SLEV and confirm their activity in central and northeastern Argentina. West Nile virus activity in Argentina may represent a potential threat to Crowned Eagles and other endangered raptors in this country.Fil: Quaglia, Agustín Ignacio Eugenio. Fundación de Historia Natural Félix de Azara; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología "Dr. J. M. Vanella"; ArgentinaFil: Diaz, Luis Adrian. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Argibay, Hernán Darío. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Ecología, Genética y Evolución; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Contigiani de Minio, Marta Silvia. Universidad Nacional de Córdoba. Facultad de Medicina. Instituto de Virología "Dr. J. M. Vanella"; ArgentinaFil: Saggese, Miguel M.. Western University of Health Sciences; Estados Unido

Modulation of gene expression in CD4+ T lymphocytes following in vitro HIV infection: a comparison between human and chimpanzee

International audienceChimpanzees are susceptible to experimental infection by human deficiency virus (HIV)-1, but unlike humans, they exceptionally develop an immunodeficiency syndrome after HIV-1 inoculation. To explore the difference between human and chimpanzee, we analyzed the expression of 1547 genes of various functions in human or chimpanzee CD4+ lymphoblasts inoculated in vitro with HIV-1. We observed that, 1 day after HIV inoculation, fifty-eight genes were up-regulated in lymphoblasts of the three humans while their expression remained unchanged in lymphoblasts of the three chimpanzees. One gene is involved in adhesion of HIV (catenin-alpha), three in the immune response (semaphorin 4D, placental growth factor, IL-6), three in apoptosis (deleted in colorectal carcinoma, caspase 9 and FOXO1A). No difference between species was revealed for the expression of 373 genes related to glycosylation pathways. The in vitro human/chimpanzee comparison reveals new candidate genes up-regulated after inoculation with HIV-1 only in human lymphoblasts and which could be related to the higher sensitivity of human to HIV-induced AIDS