The broad spectrum thio-isomerase inhibitor, DTNB, significantly reduces infection by HIV-1 Env pseudotyped virus particles. The CD4+CCR5+ HOS (panel A,B) and JC53 (panel C) cell lines, as well as the primary human MDM (panel D) and PBMC (panel E) were pre-incubated with different concentrations of DTNB for 1 h and then infected with HIV-1-Env pseudotyped virions in the presence of the inhibitor. The infection was carried out for 2.5 h at 37°C in triplicate in a serum free medium. Cells were subsequently washed with DMEM and further incubated in DM-10 for 48 h prior to lysis (0.5% Triton-100 in PBS) and measurement of Luc activity. Cell lysates from mock-infected cells and from cells not treated with DTNB were used as a negative control and control, respectively. The P values for the differences between the control and DTNB treated cells were calculated using the GraphPad Prism scientific software (t-test).