title: Primary stage of feline immunodeficiency virus infection: viral dissemination and cellular targets.
abstract: The objective of this study was to identify cellular and organ targets of acute feline immunodeficiency virus (FIV) infection in vivo. Tissues of FIV-infected cats were studied at eight time points during the first 3 months after experimental infection. FIV nucleic acids were first detected by in situ hybridization 21 days after infection, approximately 1.5 weeks after lymph node enlargement was first observed and 3 weeks before the primary acute flu-like illness. The majority of FIV-infected cells were present in lymphoid organs, though low numbers of infected cells were noted in nonlymphoid organs as well. Germinal centers harbored many of the FIV-infected cells within lymphoid tissues. The thymic cortex was also a major site of early infection. Combined in situ hybridization and immunohistochemistry revealed that T lymphocytes were the primary target of early FIV infection in tissues of cats before the onset of clinical signs of acute illness. An unidentified population of mononuclear cells and a few macrophages were also infected. During the ensuing acute flu-like illness, the proportion of FIV-infected macrophages in tissues increased dramatically. This early shift in the predominant cellular localization of FIV from T lymphocytes to macrophages may be important for establishing viral persistence.
authors.affiliation: Department of Internal Medicine, School of Medicine, University of California, Davis 95616.
authors.forename: A M
authors.initials: AM
authors.lastname: Beebe
authors.forename: N
authors.initials: N
authors.lastname: Dua
authors.forename: T G
authors.initials: TG
authors.lastname: Faith
authors.forename: P F
authors.initials: PF
authors.lastname: Moore
authors.forename: N C
authors.initials: NC
authors.lastname: Pedersen
authors.forename: S
authors.initials: S
authors.lastname: Dandekar
mesh_terms: D000818:Animals; D002415:Cats; D004279:DNA, Viral / Q000032:analysis; D016181:Feline Acquired Immunodeficiency Syndrome / Q000097:blood / Q000382:microbiology* / Q000473:pathology; D005260:Female; D016089:Immunodeficiency Virus, Feline / Q000254:growth & development*; D017403:In Situ Hybridization; D007422:Intestines / Q000382:microbiology / Q000473:pathology; D008198:Lymph Nodes / Q000382:microbiology / Q000473:pathology; D008264:Macrophages / Q000382:microbiology; D008297:Male; D012367:RNA, Viral / Q000032:analysis; D013154:Spleen / Q000382:microbiology / Q000473:pathology; D013601:T-Lymphocytes / Q000382:microbiology; D013950:Thymus Gland / Q000473:pathology; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: D004279:DNA, Viral; D012367:RNA, Viral