Induction of FcγRI on iMDDCs by IFN-γ treatment and study of HIV-1 inhibition by monoclonal and polyclonal antibodies. The percentages of infected cells in the presence of purified IgG sample no. 8 (A) or sample no. 11 (B) of purified IgA sample no. 8 (D) or of monoclonal IgG 2F5 (C) were determined on iMDDCs treated or not with IFN-γ. In some experiments, the different anti–human FcγRs were added on IFN-γ–treated iMDDCs 30 minutes prior to incubation with HIV-1_BaL-IgG ICs. Values are the mean ± SD of 3 independent wells from one representative experiment.