MoDC maturation, capacity of HIV-1 Abs to bind MoDCs, and their correlation. (A) The percentage of CD83⁺ DC-SIGN⁺ MoDCs in the coculture was determined in the presence or absence of HIV-1–specific Abs (100 μg/mL) after 48 hours of infection. All experiments were performed at least 5 times with cells from different healthy blood donors. Representative data are shown and are expressed as means ± SD. (B) The capacity of various anti–HIV-1 Abs to bind MoDCs was determined (red curve). FcγRs were blocked by adding 10 μg/mL of anti-FcγRI (CD64), anti-FcγRII (CD32), and anti-FcγRIII (CD16) to MoDCs for 30 minutes before adding the various anti–HIV-1 Abs (2G12, 4E10, 2F5, 246-D, and 4B3) at a concentration of 100 μg/mL (blue curve). The capacity of Abs to bind to FcγRs corresponds to the difference between the capacity of Abs to bind MoDCs (red value) and the capacity of Abs to bind MoDCs in the presence of anti-FcγRs Abs (blue value). Representative data are shown and are expressed as means ± SD. The correlation between the capacity of anti–HIV-1 Abs (at a concentration of 100 μg/mL, except for VRC01 and VRC03, which are 50 μg/mL) to bind to the surface of MoDCs (C) or to FcγRs (D) and MoDC maturation (fold increase in CD83⁺ DC-SIGN⁺ MoDCs) was analyzed. Data are the means ± SD of 2 independent experiments performed with cells from 2 healthy blood donors. Correlations were analyzed by calculating the Pearson correlation coefficient, with P < .05 considered significant.