Inhibition of p24 release in the supernatants of PHA-stimulated HIV-1IIIB-infected PBMC using increasing amounts of known antiviral compounds. (a) Anti-IN L-731,988. (b and c) RT inhibitors AZT and ddI, respectively. At day 7 after infection, p24 antigen in the cell culture supernatants (bars) was evaluated with an enzyme-linked immunosorbent assay kit, and the percent inhibition (lines) was calculated, assuming 0% inhibition in the non-drug-treated PBMC. Each condition was tested in five replicates, and mean values with standard deviations are indicated.