(A). FLH rapidly induced the dose-dependent secretion of pro-inflammatory cytokines. DCs from C57BL/6 mouse strain were cultured with FLH, CCH or KLH (100, 500 or 1,000 µg/ml) for 24 h, and the supernatants were collected to determine the secretion levels of IL-6, TNF-α, IL-12p40 and IL-23 using commercial ELISA kits. PBS was used as the negative control. Data are shown as mean + SEM of three independent experiments. (B). The FLH-induced, reduced up-regulation of DC maturation markers. DCs were cultured in similar conditions as in (A) and were analyzed for maturation markers (CD80, CD86, CD40 and MHC-II) by flow cytometry. (C). Effect of trypsin-digested Ox-FLH and FLH on the secretion levels of pro-inflammatory cytokines. The DCs were cultured for 24 h with Ox-FLH, native FLH or trypsin-treated FLH. The supernatants were obtained and analyzed for IL-6 and IL-12p40 using commercial ELISA kits. Data are shown as mean + SEM of two independent experiments, *p<0.p<0.05 = *, p<0.01 = ** and p<0.001 = ***, unpaired Student's t-tests.