FIGURE 6.

LPS enhances TGF-β signaling in hHSCs through down-regulation of BAMBI. A, LX2 cells were pretreated with LPS (100 ng/ml) or TNF-α (10 ng/ml) for 12 h and subsequently treated with TGF-β1 (5 ng/ml) for 30 min. A Western blot analysis for phospho-Smad2/3 was performed. B, LX2 cells were infected with Ad-IκBsr or Ad-GFP overnight, followed by treatment with LPS or TNF-α for 12 h. Subsequently, cells were treated with TGF-β1 (5 ng/ml) for 24 h. COL1A1 mRNA was measured by qPCR, and 18 S was used as an internal control. Data represent mean ± S.D. *, p < 0.05; **, p < 0.01. n.s., not significant. C, LX2 cells were transfected with siRNA BAMBI for 48 h and then treated with TGF-β1 (5 ng/ml) for an additional 24 h. BAMBI protein expression was analyzed by immunoblotting (left panel), and COL1A1 mRNA expression was measured by qPCR (right panel). Data represent mean ± S.D. *, p < 0.05.