Increased IL-6 production in C57BL/6J-Why1^MOLF/MOLF congenic mice. (A and B) Peritoneal macrophages were isolated from wild-type and Why1 congenic mice and stimulated with 2 µg/ml LTA. IL-6 or TNF mRNA was analyzed by real-time PCR at the indicated times (A) and IL-6 protein secretion was analyzed by ELISA 6 h after stimulation (B). (C) Cells were stimulated for 2 h with 100 ng/ml LPS, 2 µg/ml LTA, 200 nM CpG, 100 µM Loxoribine, or 25 µg/ml poly(I:C), and IL-6 mRNA was analyzed by real-time PCR. Data shown as mean ± range of duplicate wells (A and C) or ± SEM of triplicate wells (B). (D) Cells from wild-type and Why1 congenic mice were stimulated with 2 µg/ml LTA for the indicated times and protein was extracted for Western blot analysis of p38 activation and IκBα degradation. Total p38 served as a loading control. (E) Peritoneal macrophages from the indicated strains were stimulated with 2 µg/ml LTA for the indicated times and CCL3 mRNA was measured by real-time PCR analysis. Error bars indicate SEM. All experiments are representative of two to three independent trials.