Of note, the level of inhibition of cell-to-cell virus transmission was highly correlated with the level of inhibition of killing of bystander CD4 T cells for each of the four tested bNAbs (Fig. 2A, red lines) although inhibition of cell killing by the 10E8 bNAb, uniquely targeting the membrane proximal external region, was not quite as effective as inhibition of cell-to-cell infection in the lower dose range. This evidence concerns the gene CD4 and infection.