(A) Effect of H2O2 on CCR2, CCR5, and CXCR4 mRNA expression. Monocytes were incubated for 4 h with H2O2 at the indicated doses. (B) Effect of X/XO on the inhibitory action of PDTC on CCR2, CCR5, and CXCR4 mRNA expression. X was used at 0.5 mM; XO was used at 10 milliunits/ml. Total RNA was purified from fresh human monocytes incubated for 4 h as indicated. (C) Effect of BSO on CCR2, CCR5, and CXCR4 mRNA expression. Cells were incubated with 3 mM BSO for 18 h. Results are representative of three different experiments.