Reduction in intracellular GSH levels by 4-OH-IF. (A) T cells, NK cells, monocytes, immature DCs, and mature DCs (0.5 × 106/mL) were treated with 4-OH-IF (100 μM) for 90 minutes. Untreated cells were used as controls. Cells were then washed, and GSH levels were measured by HPLC. Results are expressed as nM GSH/mg protein, and they represent the mean ± SD from 3 separate donors. *P < .05; **P < .01. (B) T cells, NK cells, monocytes, immature DCs, and mature DCs (0.5 × 106/mL) were treated with increasing concentrations (50, 100, 200 μM) of 4-OH-IF for 90 minutes. Untreated cells were used as controls. Cells were then washed, and GSH levels were measured by HPLC. Results are expressed as the percentage of control values and represent the mean ± SD of 2 separate experiments from 2 separate donors.
