CCR5 and infection: Using HIV-1AD8 BlaM containing virus particles, we established that DTNB significantly inhibited fusion of HIV-1AD8 BlaM-containing virions with both the JC53 CD4+/CCR5+ cell line (Figure2A) and primary human PBMCs (Figure2B), as well as MDMs (Figure2C), indicating that its effect occurs predominantly at the level of virus entry and further supporting the role for thiol/disulfide exchange in HIV-1 Env during infection.