title: Long-term observations of human immunodeficiency virus-infected chimpanzees.
abstract: Twenty-seven chimpanzees inoculated with material presumed to contain human immunodeficiency virus (HIV) between June 1983 and February 1985 were studied. The animals were examined on four to six occasions between 1989 and 1992 for serologic, virologic, hematologic, immunophenotypic, as well as clinical signs of HIV infection and compared to five uninfected control animals. The 19 animals that had seroconverted within 244 days of inoculation remained antibody positive, whereas those that did not seroconvert within 244 days of inoculation remained antibody negative 6 to 8 years later. HIV antigen was demonstrated at least once in lymphocyte cultures from 12 of the 19 antibody positive chimpanzees during this period. Nested polymerase chain reaction amplified proviral DNA in lymphocytes from 14 of the 19 animals. No proviral DNA was detected in antibody-negative animals. Antibody titers were generally higher in animals from which virus was recovered in lymphocyte cultures [granulocyte-macrophage (GM) titer, 1:8427] compared to virus-negative animals (GM titer, 1:3608). Mean total white blood cell and lymphocyte subtype counts were similar in the HIV-infected animals and uninfected controls. The high antibody levels and Western blot profiles, over periods as long as 9 years in these chimpanzees, suggest continuous stimulation of the immune system by HIV antigen although virus was detected only sporadically in the peripheral blood. No illness suggestive of immunodeficiency was seen.
authors.affiliation: Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892.
authors.forename: B K
authors.initials: BK
authors.lastname: Johnson
authors.forename: G A
authors.initials: GA
authors.lastname: Stone
authors.forename: M S
authors.initials: MS
authors.lastname: Godec
authors.forename: D M
authors.initials: DM
authors.lastname: Asher
authors.forename: D C
authors.initials: DC
authors.lastname: Gajdusek
authors.forename: C J
authors.initials: CJ
authors.lastname: Gibbs
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D015483:HIV Antibodies / Q000097:blood; D015658:HIV Infections / Q000276:immunology / Q000503:physiopathology*; D006801:Humans; D002679:Pan troglodytes; D016133:Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D015483:HIV Antibodies