CD4 and infection: While VRC01 and NIH45–46 G54W inhibited cell free CCR5-tropic HIV-1 (pseudotyped with Bal Env) infection of CD4+ T cells efficiently [IC50 (VRC01) = 0.035 ± 0.005 μg/ml (Fig. 6E and H), IC50 (NIH45–46 G54W) = 0.012 ± 0.004 μg/ml (Fig. 6F and I)], transfer of LPS-DC-associated HIV-1 particles was inefficiently neutralized [IC50 (VRC01) = 1.152 ± 0.308 μg/ml (Fig. 6E and H) and IC50 (NIH45–46 G54W) = 0.223 ± 0.062 μg/ml (Fig. 6F and I)].