Figure 6
Iloprost suppressed poly I:C-induced TNF-α expression in human mDCs via the MAPK-p38-ATF2 pathway. Isolated human mDCs were pretreated with MAPK-p38 inhibitor (SB203580), MAPK-JNK inhibitor (SP600125) or MAPK-ERK inhibitor (PD98059) 1 h before poly I:C stimulation. Supernatants were collected 24 h after poly I:C stimulation for TNF-α measurement. For Western blotting analysis, mDCs were pretreated with or without iloprost (10−7 mol/L) for 2 h and then stimulated with poly I:C for 1 h, and cell lysates were collected. (A) All MAPK inhibitors suppressed poly I:C-induced TNF-α expression. Iloprost suppressed poly I:C-induced phospho-p38 (B) and phospho-ATF2 (C) expression. Result of TNF-α expression represented the mean ± SD of six independent experiments using mDCs from six subjects. For Western blotting analyses, one experiment representative of three is shown. *P < 0.05 compared with poly I:C-treated cells.