title: New strain of simian immunodeficiency virus identified in wild-born chimpanzees from central Africa.
abstract: Studies of primate lentiviruses continue to provide information about the evolution of simian immunodeficiency viruses (SIVs) and the origin and emergence of HIV since chimpanzees in west-central Africa (Pan troglodytes troglodytes) were recognized as the reservoir of SIVcpzPtt viruses, which have been related phylogenetically to HIV-1. Using in-house peptide ELISAs to study SIV prevalence, we tested 104 wild-born captive chimpanzees from Gabon and Congo. We identified two new cases of SIVcpz infection in Gabon and characterized a new SIVcpz strain, SIVcpzPtt-Gab4. The complete sequence (9093 bp) was obtained by a PCR-based 'genome walking' approach to generate 17 overlapping fragments. Phylogenetic analyses of separated genes (gag, pol-vif and env-nef) showed that SIVcpzPtt-Gab4 is closely related to SIVcpzPtt-Gab1 and SIVcpzPtt-Gab2. No significant variation in viral load was observed during 3 years of follow-up, but a significantly lower CD4+ T cells count was found in infected than in uninfected chimpanzees (p<0.05). No clinical symptoms of SIV infection were observed in the SIV-positive chimpanzees. Further field studies with non-invasive methods are needed to determine the prevalence, geographic distribution, species association, and natural history of SIVcpz strains in the chimpanzee habitat in Gabon.
authors.affiliation: Unité de Rétrovirologie, Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, Gabon.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Souquière
authors.forename: Maria
authors.initials: M
authors.lastname: Makuwa
authors.forename: Bettina
authors.initials: B
authors.lastname: Sallé
authors.forename: Mirdad
authors.initials: M
authors.lastname: Kazanji
mesh_terms: D000350:Africa, Central; D000595:Amino Acid Sequence; D000818:Animals; D000835:Animals, Wild / Q000276:immunology / Q000821:virology*; D015153:Blotting, Western; D005260:Female; D015752:Genes, env; D016679:Genome, Viral / Q000235:genetics; D005843:Geography; D008297:Male; D008969:Molecular Sequence Data; D002679:Pan troglodytes / Q000276:immunology / Q000821:virology*; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D016097:Simian Acquired Immunodeficiency Syndrome / Q000097:blood / Q000276:immunology / Q000821:virology; D015302:Simian Immunodeficiency Virus / Q000276:immunology / Q000302:isolation & purification* / Q000502:physiology; D014764:Viral Proteins / Q000737:chemistry / Q000235:genetics; D014779:Virus Replication / Q000502:physiology
chemical_list: D012367:RNA, Viral; D014764:Viral Proteins