Long-term persistent infection of macaque monkeys with the simian immunodeficiency virus

Juvenile rhesus macaques 6 to 18 months of age were experimentally infected by intravenous inoculation with the simian immunodeficiency virus (SIV), the T cell-tropic retrovirus of monkeys related to the human acquired immunodeficiency syndrome (AIDS) virus HIV. The SIV used for inoculation was grown either in normal human peripheral blood lymphocytes in the presence of interleukin 2or in the human tumour cell line HUT-78. Eight of the macaques died 129 to 352 days post-inoculation with a variety of clinical and pathological findings paralleling those of AIDS in humans. However eight other animals became persistently infected ~br prolonged periods; these eight macaques remained alive at 537 and 820 days post-inoculation despite persistent lymphadenopathy and our continued ability to isolate SIV. The ability of these monkeys to survive infection correlated irectly with the strength of their antibody response to SIV. Infection was also established in macaques using approximately 100 tissue culture infectious doses of HUT-78-grown SIV. There was no correlation between the dose of virus inoculum and either the strength of the antibody response or clinical outcome. These results demonstrate hat SIV infection of macaque