FIG. 1.
Ability of microbicide product and placebo formulations to block clade B HIV-1BaL transfer from A431 epithelial cell lines to activated PBMCs. Epithelial cell lines were cultured overnight with virus and nontoxic epithelial concentrations of product or placebo. The cells were washed, and activated PBMCs were added. Virus infection of the PBMCs was monitored using the HIV-1 p24gag enzyme-linked immunosorbent assay. The data presented are the averages ± standard errors of the means from at least two independent experiments. Cultures that were positive for HIV infection had HIV-1 p24 levels of >1 ng/ml, as indicated by the horizontal line. Product dilutions were 1:50 for CAP, 1:10 for HEC, 1:25 for PRO 2000 and placebo, 1:25 for SPL7013 and placebo, and 1:10 for UC781 and placebo (9). The formulated microbicide is listed along with its placebo designated by the small “p.”