Fig. 4.

(a) Induction of interleukin (IL)-32 expression by Toll-like receptor (TLR)-3 ligand (poly I:C) and cytokines in cultured biliary epithelial cells (BECs). Quantitative analysis using real-time polymerase chain reaction (PCR) revealed that a TLR-3 ligand, poly(I:C) and proinflammatory cytokines [interleukin (IL)-1β, interferon (IFN)-γ and tumour necrosis factor (TNF)-α], but not regulatory cytokines [transforming growth factor (TGF)-β1 and IL-10], up-regulated significantly the mRNA expression of IL-32. (b) Detection of BEC-producing cytokines (IL-1β, IL-6 and IL-32), TLR-3 and caspase 1 in cultured BECs. The stimulation with IL-32 did not up-regulate the expression of any cytokines, TLR-3 or caspase 1 significantly. (c) Detection of IL-32 in a control cell line, HepG2. Induction of IL-32 expression was not found by stimulation with poly(I:C) or IL-32. Results were obtained from three independent experiments and shown as relative mRNA expression compared with the level without any treatments (Non). Bars indicate the mean ± standard error of the mean. *P < 0·05.