Inhibition of replication of HIV in primary monocyte/macrophages by different antiviral drugs and comparative efficacy in lymphocytes

Several anti-HIV drugs acting on different steps of virus replication were tested in our experi- mental model ofprimary monocyte/macrophages; the results were compared with the activity found in lym- phocytes. Nucleoside analogues (AlT, ddl, ddC, d4T, PMEA, 3TC etc.) show greater activity in macrophages (MIM) than in lymphocytes. hi particular, the EC50 of AZT, ddC, and ddl in M/M is 2- to 100-fold lower than that found in lymphocytes. This greater efficacy of nucleoside analogues in M/M depends on the en- hancement oftheir chain-terminating activity by the low levels of endogenous deoxynucleoside-triphosphates (dNTP) usually found in resting cells such as MIM. Non-