PDTC inhibits TsAg- and LPS-induced CXCL8 and CCL2 secretion in monocytes. Monocytes were pre-incubated for 2 h with 1, 10, or 100 μM PDTC prior to stimulation with either 100 μg/ml TsAg (black bars) or 10 μg/ml LPS (open bars) for 24 h. Cell-free culture supernatants were subsequently collected and analysed for (A,B) CXCL8 and (C,D) CCL2 by ELISA. PDTC alone (100 μM) has no effect on either CXCL8 or CCL2 secretion. Data are expressed as mean SEM of a triplicate experiment, which is representative of two independent experiments. Differences between groups were analysed for statistical significance using Student’s t-test.