Fig. (2) Productive HIV-1 infection of CD8+ T-cells in vitro. (A) RT-PCR analysis of HIV-gag transcripts in the uninfected and infected populations of isolated CD4+ and CD8+ T-cells. Isolated lymphocyte populations were left uninfected or infected with 300 TCID₅₀/mL of HIV_IIIB for 7 days prior to RT-PCR analysis. Detection of β-actin was run as a loading control. Parallel samples were run without reverse transcriptase as a control for DNA contamination of the samples (data not shown). (B) Infection of CD8+ T-cells is sensitive to AZT. Infection was performed in the absence and presence of AZT and HIV-1 production was measured by an ELISA for the HIV-1 gag protein, p24. Cells were treated with 10 µM of AZT for one hour prior to infection. CD8+ T-cells from two uninfected individuals were infected with 300 TCID₅₀/mL of HIV_IIIB laboratory strain. The results shown are the mean and SEM of three independent experiments.