title: Virus subtype-specific features of natural simian immunodeficiency virus SIVsmm infection in sooty mangabeys.
abstract: Simian immunodeficiency virus (SIV) SIV(smm) naturally infects sooty mangabeys (SMs) and is the source virus of pathogenic infections with human immunodeficiency virus type 2 (HIV-2) and SIV(mac) of humans and macaques, respectively. In previous studies we characterized SIV(smm) diversity in naturally SIV-infected SMs and identified nine different phylogenetic subtypes whose genetic distances are similar to those reported for the different HIV-1 group M subtypes. Here we report that, within the colony of SMs housed at the Yerkes National Primate Research Center, at least four SIV(smm) subtypes cocirculate, with the vast majority of animals infected with SIV(smm) subtype 1, 2, or 3, resulting in the emergence of occasional recombinant forms. While SIV(smm)-infected SMs show a typically nonpathogenic course of infection, we have observed that different SIV(smm) subtypes are in fact associated with specific immunologic features. Notably, while subtypes 1, 2, and 3 are associated with a very benign course of infection and preservation of normal CD4+ T-cell counts, three out of four SMs infected with subtype 5 show a significant depletion of CD4+ T cells. The fact that virus replication in SMs infected with subtype 5 is similar to that in SMs infected with other SIV(smm) subtypes suggests that the subtype 5-associated CD4+ T-cell depletion is unlikely to simply reflect higher levels of virus-mediated direct killing of CD4+ T-cells. Taken together, this systematic analysis of the subtype-specific features of SIV(smm) infection in natural SM hosts identifies subtype-specific differences in the pathogenicity of SIV(smm) infection.
authors.affiliation: Division of Microbiology and Immunology, Tulane National Primate Research Center, 18703 Three Rivers Road, Covington, LA 70433, USA. capetrei@tulane.edu
authors.forename: Cristian
authors.initials: C
authors.lastname: Apetrei
authors.forename: Rajeev
authors.initials: R
authors.lastname: Gautam
authors.forename: Beth
authors.initials: B
authors.lastname: Sumpter
authors.forename: Anders C
authors.initials: AC
authors.lastname: Carter
authors.forename: Thaidra
authors.initials: T
authors.lastname: Gaufin
authors.forename: Silvija I
authors.initials: SI
authors.lastname: Staprans
authors.forename: James
authors.initials: J
authors.lastname: Else
authors.forename: Mary
authors.initials: M
authors.lastname: Barnes
authors.forename: Robert
authors.initials: R
authors.lastname: Cao
authors.forename: Seema
authors.initials: S
authors.lastname: Garg
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Milush
authors.forename: Donald L
authors.initials: DL
authors.lastname: Sodora
authors.forename: Ivona
authors.initials: I
authors.lastname: Pandrea
authors.forename: Guido
authors.initials: G
authors.lastname: Silvestri
mesh_terms: D000818:Animals; D016665:Cercocebus atys / Q000821:virology*; D005260:Female; D015686:Gene Products, env / Q000145:classification / Q000235:genetics / Q000378:metabolism; D015683:Gene Products, gag / Q000145:classification / Q000235:genetics / Q000378:metabolism; D015684:Gene Products, pol / Q000145:classification / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D010802:Phylogeny; D016097:Simian Acquired Immunodeficiency Syndrome / Q000821:virology*; D015302:Simian Immunodeficiency Virus / Q000145:classification / Q000235:genetics* / Q000502:physiology; D014779:Virus Replication
chemical_list: D015686:Gene Products, env; D015683:Gene Products, gag; D015684:Gene Products, pol