HIV AND SIV ENVELOPE GLYCOPROTEINS INDUCE PHOSPHOLIPASE A(2) ACTIVATION IN HUMAN AND MACAQUE LYMPHOCYTES

We investigated the early interactions between HIV-1, HIV-2, and simia n immunodeficiency virus (SIV) envelope glycoproteins gp120(IIIB), gp1 05(ROD), and gp120(mac251), and human and macaque cells of the lymphoc ytic series. Our results demonstrate that the soluble viral glycoprote ins induce a specific phospholipase A(2) (PLA(2)) activation in lympho cytes through CD4. This PLA(2) activation was induced after envelope g lycoprotein-CD4 interaction and, because of its local membrane-destabi lizing effect, may have important implications for preparing the lymph ocyte membrane for fusion with the viral particle. However, this effec t is not sufficient to accomplish fusion. These data indicate that the specific step of fusion may be downstream from PLA(2) activation.