EZH2 and G9a knockdown alters repressive histone methylation at the CXCL10 promoter in F-IPF. F-IPF cells were transfected with control siRNA, EZH2 siRNA, or G9a siRNA before being treated with IL-1β (1 ng/ml) for a further (A) 24 hours or (B and C) 4 hours. (A) Total cell lysates were collected for Western blot analysis of EZH2 and G9a with β2M as the loading control. This is representative of three separate experiments with different F-IPF cell lines. Chromatin immunoprecipitation was conducted with specific antibodies against (B) H3K27me3, (C) H3K9me3, and (B and C) total histone H3. (B and C) The associated CXCL10 promoter DNA was amplified by real-time RT-PCR, and the amount was calculated and normalized to total histone H3. Data are expressed as mean ± SEM of experiments with six separate F-IPF cell lines performed in duplicate. *P < 0.05, **P < 0.01 compared with corresponding untreated cells.