title: Paucity of CD4+CCR5+ T cells is a typical feature of natural SIV hosts.
abstract: In contrast to lentiviral infections of humans and macaques, simian immunodeficiency virus (SIV) infection of natural hosts is nonpathogenic despite high levels of viral replication. However, the mechanisms underlying this absence of disease are unknown. Here we report that natural hosts for SIV infection express remarkably low levels of CCR5 on CD4+ T cells isolated from blood, lymph nodes, and mucosal tissues. Given that this immunologic feature is found in 5 different species of natural SIV hosts (sooty mangabeys, African green monkeys, mandrills, sun-tailed monkeys, and chimpanzees) but is absent in 5 nonnatural/recent hosts (humans, rhesus, pigtail, cynomolgus macaques, and baboons), it may represent a key feature of the coevolution between the virus and its natural hosts that led to a nonpathogenic infection. Beneficial effects of low CCR5 expression on CD4+ T cells may include the reduction of target cells for viral replication and a decreased homing of activated CD4+ T cells to inflamed tissue.
authors.affiliation: Tulane National Primate Research Center, Covington, LA 70433, USA. ipandrea@tulane.edu
authors.forename: Ivona
authors.initials: I
authors.lastname: Pandrea
authors.forename: Cristian
authors.initials: C
authors.lastname: Apetrei
authors.forename: Shari
authors.initials: S
authors.lastname: Gordon
authors.forename: Joseph
authors.initials: J
authors.lastname: Barbercheck
authors.forename: Jason
authors.initials: J
authors.lastname: Dufour
authors.forename: Rudolf
authors.initials: R
authors.lastname: Bohm
authors.forename: Beth
authors.initials: B
authors.lastname: Sumpter
authors.forename: Pierre
authors.initials: P
authors.lastname: Roques
authors.forename: Preston A
authors.initials: PA
authors.lastname: Marx
authors.forename: Vanessa M
authors.initials: VM
authors.lastname: Hirsch
authors.forename: Amitinder
authors.initials: A
authors.lastname: Kaur
authors.forename: Andrew A
authors.initials: AA
authors.lastname: Lackner
authors.forename: Ronald S
authors.initials: RS
authors.lastname: Veazey
authors.forename: Guido
authors.initials: G
authors.lastname: Silvestri
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000473:pathology* / Q000821:virology; D002634:Chemotaxis, Leukocyte; D007958:Leukocyte Count; D009000:Monocytes / Q000473:pathology / Q000821:virology; D019713:Receptors, CCR5; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology*; D015302:Simian Immunodeficiency Virus / Q000502:physiology; D014779:Virus Replication
chemical_list: D019713:Receptors, CCR5