C/EBPβ and A20 (TNFAIP3) were suppressed in Ikkβ^Δ and p38-inhibited macrophages.

(A–C) Expression levels of Tnfaip3 and Cebpb mRNA were decreased in Ikkβ^Δ and p38-inhibited BMDMs in response to LPS. BMDMs from wt and Ikkβ^Δ cells treated with or without SB202190 (10 µM) were stimulated with LPS (100 ng/mL) for 4 h. Total RNAs were isolated and analyzed by semi-quantitative RT-PCR (A) or quantitative real-time RT-PCR for expression of Cebpb (B) and Tnfaip3 (C) mRNAs. Results were normalized to Cyclophilin A (Cypa) and are presented relative to expression in wt BMDMs. *P<0.05. (D) A20 (TNFAIP3) protein levels were decreased in p38-inhibited (SB202190) and Ikkβ^Δ BMDMs after LPS treatment. (E) Temporal profiles of A20, C/EBPβ, and C/EBPδ in p38-inhibited RAW264.7 cells after LPS treatment for the indicated duration. Cell lysates were prepared and analyzed by immunoblotting with the indicated antibodies.