RESUMO
Serum samples from 850 individuals from Venezuela were tested for the presence of antibodies to HTLV-III/LAV virus, the probable etiological agent of acquired immune deficiency syndrome (AIDS). At the time of the study, none of the individuals tested had symptoms indicative of AIDS or related disorders. Viral antibodies were assayed by indirect immunofluorescence (IF) assay, using a chronically infected, HTLV-III/LAV producer cell line CEM/LAV-NIT established in our laboratory. Twenty individuals (2.5%), 8 of them (40%) female, were seropositive by IF and by confirmatory Western blotting and radioimmunoprecipitation assays. The seropositivity rate ranged from 2.4% (11 of 465) in the general healthy population, 4% (2 of 50) among patients with Chagas' disease, and up to 29.2% (7 of 24) among patients with acute malaria infection. The titers of HTLV-III/LAV antibodies ranged from 1:40 to 1:640. In addition, 2 of 36 patients with hemophilia A (5.5%) also had antibodies to HTLV-III/LAV. Two of 7 patients with acute malaria had specific antibodies both to HTLV-III/LAV and HTLV-I, as determined by IF and Western blotting. None of over 169 randomly chosen, healthy blood donors from seven major Venezuelan cities, as well as none of 99 patients with leukemia/lymphoma, had antibodies to HTLV-III/LAV. The presence of specific antibodies among various Venezuelan populations indicates that HTLV-III/LAV, or a closely related cross-reactive virus, is indigenous in Latin American subjects as was previously indicated for tropical populations of central Africa. Isolation and characterization of this virus will help to understand the origin and etiology of AIDS.
Assuntos
Anticorpos Antivirais/análise , Deltaretrovirus/imunologia , Síndrome da Imunodeficiência Adquirida/etiologia , Adolescente , Adulto , Idoso , Linhagem Celular , Criança , Pré-Escolar , Feminino , Imunofluorescência , Anticorpos Anti-HIV , Hemofilia A/microbiologia , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , VenezuelaRESUMO
Serum samples from 224 aboriginal Amazonian Indians were tested for antibodies to HTLV-III/LAV by an indirect immunofluorescence (IF) assay. 9 individuals (4%), 5 of them female, were seropositive by IF and by confirmatory western blotting and radioimmunoprecipitation tests. 3 of the positive sera were collected in 1968. HTLV-III/LAV seropositivity rates varied among the ethnic groups and ranged from 13.3% among the Pemon Indians to 3.3% among the Yanoama tribe. The titres of HTLV-III/LAV antibodies ranged from 1/40 to 1/320. All individuals tested were apparently healthy at the time of the study. None of 211 randomly chosen, healthy blood donors from Venezuelan cities had antibodies to HTLV-III/LAV. The prevalence of specific antibodies among Amazonian Indians suggests the HTLV-III/LAV or a closely related cross-reactive virus may be endemic in this area. The findings also indicate that this virus is indigenous in non-negroid Latin American and negroid tropical populations.