FIG. 2.

H. pylori-treated DCs can produce IL-12 in response to H. pylori when CD40 is ligated. (A and B) DCs were incubated with medium (diamonds), H. pylori (10⁶ CFU/ml; squares), E. coli (10⁸ CFU/ml; circles), and LPS (100 ng/ml; triangles) for 24 h in the presence of CD40L-Tx (filled symbols) or in the absence of CD40L stimulation (open symbols). IL-10 (A) and IL-12 (B) production was measured by ELISA. Each dot represents one experiment for a total of 10. *, P < 0.05 (Wilcoxon signed-rank test compared to medium alone); #, P < 0.05 (Wilcoxon signed-rank test compared to medium plus CD40L-Tx). (C and D) DCs were incubated alone (medium) or with H. pylori live or dead (10⁵ to 10⁷ CFU/ml) in the absence or in the presence of CD40L-Tx cells for 24 h before the supernatants were removed, and IL-10 and IL-12 levels were analyzed by ELISA.