Silencing of IRF8 expression by siRNA inhibited TNF-α-induced apoptosis in SL4-CXCL16. (A) Knockdown of IRF8 expression by qRT-PCR and Western blot analysis. (B) Viability of IRF8 knockdown cells stimulated with TNF-α. Cells were seeded in 96-well plates (2 × 103 cells) and stimulated with TNF-α (10 ng/ml) for 0–72 h and then viability was measured by the WST-8 assay. *P <0.05. (C) Annexin V assay. Cells were seeded in 6-well plates (2 × 105 cells) and treated with TNF-α (10 ng/ml). (D) Effects of IRF8 knockdown on TNF-α-induced apoptotic responses. C, si-Control; I, si-IRF8. All experiments were repeated at least three times.