title: Emergence of cytotoxic T lymphocyte escape mutations in nonpathogenic simian immunodeficiency virus infection.
abstract: Although CTL escape has been well documented in pathogenic simian immunodeficiency virus (SIV) infection, there is no information on CTL escape in nonpathogenic SIV infection in nonhuman primate hosts like the sooty mangabeys. CTL responses and sequence variation in the SIV nef gene were evaluated in one sooty mangabey and one rhesus macaque inoculated together with the same stock of cloned SIVmac239. Each animal developed an immunodominant response to a distinct CTL epitope in Nef, aa 157-167 in the macaque and aa 20-28 in the mangabey. Nonsynonymous mutations in their respective epitopes were observed in both animals and resulted in loss of CTL recognition. These mutations were present in the majority of proviral DNA sequences at 16 weeks post infection in the macaque and >2 years post infection in the mangabey. These results document the occurrence of CTL escape in a host that does not develop AIDS, and adds to the growing body of evidence that CTL exert significant selective pressure in SIV infection.
authors.affiliation: Division of Immunology, New England Regional Primate Research Center, Harvard Medical School, Southborough, MA 01772, USA. amitinder_kaur@hms.harvard.edu
authors.forename: A
authors.initials: A
authors.lastname: Kaur
authors.forename: L
authors.initials: L
authors.lastname: Alexander
authors.forename: S I
authors.initials: SI
authors.lastname: Staprans
authors.forename: L
authors.initials: L
authors.lastname: Denekamp
authors.forename: C L
authors.initials: CL
authors.lastname: Hale
authors.forename: H M
authors.initials: HM
authors.lastname: McClure
authors.forename: M B
authors.initials: MB
authors.lastname: Feinberg
authors.forename: R C
authors.initials: RC
authors.lastname: Desrosiers
authors.forename: R P
authors.initials: RP
authors.lastname: Johnson
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016665:Cercocebus atys; D018984:Epitopes, T-Lymphocyte; D008253:Macaca mulatta; D008969:Molecular Sequence Data; D009154:Mutation; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology* / Q000821:virology; D015302:Simian Immunodeficiency Virus / Q000235:genetics* / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D019562:Viral Load; D054334:Viral Regulatory and Accessory Proteins / Q000737:chemistry / Q000276:immunology
chemical_list: D018984:Epitopes, T-Lymphocyte; C429284:NEF protein, SIV; D054334:Viral Regulatory and Accessory Proteins