On the other hand, although blocking the CD4 receptor did not affect the formation of cellular conjugates (Figure 2B), the addition of α-CD4 mAb Leu3a successfully inhibited productive infection of CD4+ T cells through mDC-mediated trans-infection of HIV-1 by hampering binding of HIV-1 Env to the CD4 molecule in target cells (p < 0.05, Figure 3B). This evidence concerns the gene CD4 and infection.