Fig. 1.

DEPs down-regulate IL-10 and TGF-β protein in a dose dependent manner. (a) PBMCs from 22 donors were cultured at 2 × 10⁶ cells/ml, primed with a median dose of 10 ng/ml LPS, and stimulated with 0, 1, 3, 10, 30 or 100 ng/ml of DEP. IL-10 production was assessed by ELISA after 48 h. IL-10 production is significantly (P < 0·05) suppressed by 1 and 3 ng/ml DEP, and is also decreased (P < 0·06) by 10 and 30 ng/ml DEP. (b) Cultures from 16 subjects were also examined by ELISA for TGF-β production after 48 h of incubation. TGF-β decreased with 1 and 3 ng/ml of DEP, and fell significantly with 10 ng/ml DEP. *P < 0·05 compared to 0; †P = 0·06 compared to 0.