Ability of HIV-1–infected CD4⁺ T cells and HIV-1–infected macrophages to induce proliferation of HIV-1–specific CTLs. Eleven HLA-B*5101-restricted CTL clones (Pol283-8-340, -320, -237, and -240; Gag327-9-148, -142, -287, and -131; Rev71-11-8, -55, and -17) were cocultured for 96 hours with uninfected macrophages, irradiated JRFL_{NL-432 Nef}-infected macrophages (17.8% p24 antigen-positive), JRFL_{NL-M20A Nef}-infected macrophages (23.2% p24 antigen-positive), uninfected CD4⁺ T cells, JRFL_{NL-432 Nef}-infected CD4⁺ T cells (20.8% p24 antigen-positive), or JRFL_{NL-M20A Nef}-infected CD4⁺ T cells (24.8% p24 antigen-positive) at an E/S ratio of 1:4. The incorporation was measured after an additional 16-hour incubation. (A) Typical example of ³H-incorporation in HLA-B*5101-restricted CTL clones (Pol283-8-340, Gag327-9-148, and Rev71-11-17), and HLA-mismatched CTL clone. Data shown in this figure are averages ± SD of triplicate assays. (B) Average ± SD of proliferation in triplicate assays for 4 Pol283-8–, 4 Gag327-9–, or 3 Rev71-11–specific CTL clones.