Anti-HIV compound assessment by two novel high capacity assays

Two novel, semi-automated assays for the assessment of compounds for activity against human immunodeficiency virus (HIV) are described. One assay uses quantitation of DNA by fluorescence to monitor reversal by test compounds of HIV-induced growth inhibition. The second assay measures the amount of HIV p24 by an indirect immunofluorescent technique. Both assays are sufficiently sensitive to allow multiple sampling of 96-well plates. Intra- and inter-assay variability were within acceptable limits. The two assays provide comparable results for given compounds. Retrovir (3'-azido, 3'-deoxythymidine, AZT) protected MT4 cells from HIV-induced growth inhibition, and inhibited the production of HIV p24. Consistent with the results of others, the anti-HIV potency of AZT was dependent on the concentration of the infecting virus. Interestingly, AZT-protected, HIV-infected MT4 cells grew faster than mock-infected MT4 cells, and inclusion of Interleukin 2 in the assay eliminated this effect.