Functional PDI is necessary for successful HIV-1 infection. HIV-1_LAV was incubated with pm-1 cells for a 2-hour adsorption period. Inhibitors (1 mM DTNB, 25 μg/mL monoclonal anti-PDI Abs, and 40 μg/mL polyclonal anti-PDI Abs) were added after the viral adsorption period and replenished with media replacement every 2 days thereafter (days 4, 6, and 8). Isotype controls for MAb and PAb were included at concentrations equivalent to anti-PDI Abs. Values shown correspond to RT activity measured in supernatants harvested during the course of infection on days 4, 6, 8, and 10 and reflect the best fits of sample means that differed by not more than 15%. Data shown are representative of 2 experiments.