Ifosfamide reduces IL-12p70 production by LPS- and IFN-γ-stimulated DCs. (A).DCs were treated with 4-OH-IF for 90 minutes or with 4-OH-IF and then GSH-OEt at a final concentration of 0.4 mM for 5 hours. Untreated cells were used as controls. DCs at 5 × 10⁴/well were then treated with 1 μg/mL LPS and 1 ng/mL IFN-γ for 24 hours, after which the supernatants were collected and IL-12p70 levels determined using ELISA. Results represent the mean ± SD of triplicate samples from 3 separate experiments. ^**P < .01. (B) 4-OH-IF- and 4-OH-IF plus GSH-OEt-treated DCs were washed, and GSH levels were measured by HPLC. Untreated cells were used as controls. Results are expressed as the percentage of control values and represent the mean ± SD from 3 treatments. ^**P < .01.