Fig. 2.

Cell-type-specific requirement of IRF5 for Fas-induced apoptosis. Bone-marrow-derived DCs were prestimulated with 0.35 μM CpG-B or 100 ng/ml LPS for 24 h and then treated with Jo2 mAb (100 ng/ml) and protein A (100 ng/ml) for 16 h. Thymocytes were incubated with or without Jo2 mAb plus protein A for 18 h. MEFs were incubated with or without Jo2 mAb plus protein A in the presence of 1 μg/ml cycloheximide for 18 h. Because cycloheximide was required to make MEFs sensitive to Fas, apoptosis occurred independently of de novo protein synthesis. The values represent the mean of three independent experiments ± SD.