The Vif and Vpr accessory proteins independently cause HIV-1-induced T cell cytopathicity and cell cycle arrest.

HIV type I (HIV-1) can cause G(2) cell cycle arrest and death of CD4(+) T lymphocytes in vitro and inexorable depletion of these cells in vivo. However, the molecular mechanism of viral cytopathicity has not been satisfactorily elucidated. Previously, we showed that HIV-1 kills T cells by a necrotic form of cell death that requires high level expression of an integrated provirus but not the env or nef genes.

Cytopathic killing of peripheral blood CD4(+) T lymphocytes by human immunodeficiency virus type 1 appears necrotic rather than apoptotic and does not require env.

An important unresolved issue of AIDS pathogenesis is the mechanism of human immunodeficiency virus (HIV)-induced CD4(+) T-lymphocyte destruction. We show here that HIV type 1 (HIV-1) exerts a profound cytopathic effect upon peripheral blood CD4(+) T lymphocytes that resembles necrosis rather than apoptosis. Necrotic cytopathology was found with both laboratory-adapted strains and primary isolates of HIV-1.