Control of viremia in simian immunodeficiency virus infection by CD8(+) lymphocytes

Clinical evidence suggests that cellular immunity is involved in controllin g human immunodeficiency virus-1 (HIV-1) replication. An animal model of ac quired immune deficiency syndrome (AIDS), the simian immunodeficiency virus (SIV)-infected rhesus monkey, was used to show that virus replication is n ot controlled in monkeys depleted of CD8(+) Lymphocytes during primary SIV infection. Eliminating CD8(+) lymphocytes from monkeys during chronic SIV i nfection resulted in a rapid and marked increase in viremia that was again suppressed coincident with the reappearance of SIV-specific CD8(+) T cells. These results confirm the importance of cell-mediated immunity in controll ing HIV-1 infection and support the exploration of vaccination approaches f or preventing infection that will elicit these immune responses.