FIG. 2.

Effect of NOS inhibitors on HIV-1 replication in PHA-activated PBMC. Human PBMC were stimulated with PHA (1 μg/ml) and infected with HIV-1. l-NIL (100 or 1,000 μM), l-NMMA (500 μM), d-NMMA (500 μM), and anti-TNF-α (10 μg/ml) were added to the cultures as indicated. (A) Effect on HIV-1 replication. Three days after infection, cultures were assayed in triplicate for viral HIV-1 p24 Ag content in the supernatants by an Ag capture immunoassay. Differences are significant for anti-TNF-α (P < 0.01), 1,000 μM l-NIL (P < 0.01) and 500 μM l-NMMA (P < 0.05). (B) Effect on cell proliferation. Proliferation was measured by [³H]thymidine incorporation during the last 16 h of the 3-day cultures. Data shown are the means ± SD of four independent experiments from four blood donor samples.