Human immunodeficiency virus-2 infection in baboons is an animal model for human immunodeficiency virus pathogenesis in humans.

OBJECTIVE

To assess disease progression in baboons (Papio cynocephalus) that were infected with two human immunodeficiency virus-2 (HIV-2) isolates.

METHODS

Eight baboons were inoculated intravenously with either HIV-2UC2 or HIV-2UC14 and were followed for a 2- to 7-year period of observation.

RESULTS

Six of 8 baboons showed lymphadenopathy and other signs of HIV-related disease, 3 of 8 baboons had an acute phase CD4+ T-cell decline, and 2 of 5 baboons infected with the HIV-2UC2 isolate progressed to an acquired immunodeficiency syndrome-like disease. Human immunodeficiency virus-2-specific pathology in lymphatic tissues included follicular lysis, vascular proliferation, and lymphoid depletion. Both neutralizing antibodies and a CD8+ T-cell antiviral response were associated with resistance to disease.

CONCLUSIONS

Disease progression and the development of acquired immunodeficiency syndrome in HIV-2-infected baboons have similarities to human HIV infections.