CONTRIBUTION TO THE REGULATION OF VIRUS-REPLICATION IN CELLS LATENTLYINFECTED WITH HUMAN-IMMUNODEFICIENCY-VIRUS-1

Monocytes/macrophages have been known to play an important role in the initiation and propagation of human immunodeficiency virus 1 (HIV-1) infection. To analyze the function of these cells during the clinical asymptomatic period of infection, we examined the effect of murine per itoneal macrophages and human peripheral blood macrophages on two cell lines latently infected with HIV-1, a promonocytic cell line, U1, and a T-cell line, ACH-2. Monokines of the murine peritoneal macrophages induced significant viral expression in U1, bur not in ACH-2 cells. Ex periments employing transient transfection of U937 and CEM cells with HIV long terminal repeat (LTR)-chloramphenicol acetyl transferase (CAT ) plasmids indicated that the effect of these monokines was due to spe cific activation of the HIV LTR. In contrast, supernatants of human ma crophages induced viral expression in both ACH-2 and U1 cells. These r esults suggest that several monokines are active in regulating the tra nsition from the clinical asymptomatic period of HIV infection to prog ression to acquired immunodeficiency syndrome (AIDS).