Effects of inhibitors of transcription factors, nuclear factor-κB and activator protein 1, on the expression of proinflammatory cytokines and chemokines induced by stimulation with Toll-like receptor ligands in hen vaginal cells.

The goal of this study was to determine whether nuclear factor-κB (NFκB) and activator protein 1 (AP-1) were the responsible transcription factors for the induction of proinflammatory cytokines in hen vaginal cells stimulated by different Toll-like receptor (TLR) ligands. Cultured vaginal cells were treated with or without poly I:C (TLR3 ligand; dsRNA virus), lipopolysaccharide (LPS) (TLR4 ligand; gram-negative bacteria), flagellin (TLR5 ligand; bacterial flagellum), R848 (TLR7 ligand; ssRNA virus), and CpG-oligodeoxynucleotide (CpG-ODN) (TLR21 ligand; bacteria and DNA virus) in the presence or absence of different doses of BAY11-7085 (NFκB inhibitor) and tanshinone IIA (AP-1 inhibitor). Then, gene expressions of IL1B, IL6, and CXCLi2 were examined by real-time PCR analysis. The results showed that the induction of the expression of IL1B, IL6 and CXCLi2 by poly I:C, LPS, and CpG-ODN were suppressed by Bay11-7085, but not by tanshinone IIA. IL1B expression was upregulated by flagellin and R848, and the increase in its expression was suppressed by Bay11-7085, but not by tanshinone. These results suggest that NFκB is the responsible transcription factor for the expression of proinflammatory cytokines and chemokines, including I IL1B, IL6, and CXCLi2 in response to the ligands of TLR3, 4, and 21, and IL1B in response to the ligands of TLR5 and 7 in the vaginal cells.