FIG. 3.

CM from uNK cells inhibit infection of PBMC and primary FRT cells by HIV-1. (A) PHA-activated PBMCs were incubated with media or with CM from IL-12- plus IL-15-stimulated uNK cells (uNK CM), followed by infection with HIV-1 (IIIB +). Following infection, supernatant was collected from the PBMC cultures on days 3, 5, and 7 and added to TZM-bl cell cultures to quantify the amount of infectious HIV-1. After 48 h of incubation with TZM-bl cells, β-Gal activity was determined. Controls included supernatants from uninfected PBMCs (−). These data are representative of three independent experiments and are means ± SEM (n = 4). ***, P < 0.001. (B) PHA-activated endometrial cells from human uterine tissues were treated as in panel A, and cell-free supernatants collected on days 3 and 5 were tested for the presence of infectious HIV using TZM-bl reporter cells. Results are shown as means ± SEM (***, P < 0.001) and represent three independent experiments, and samples from different donors were used in each experiment.