FIG. 1.
Anti-CD40, TNF, or LPS stimulation upregulates FLIP and partly protects from FasL-mediated apoptosis. (A) A20 lymphoma cells were pretreated for 24 h with anti-CD40 at 10 μg/ml and treated with recombinant Flag-tagged FasL (33 ng/ml) in the presence of cross-linking anti-Flag antibodies at 1 μg/ml for 8 h. Apoptosis was quantified by annexin V staining, and FLIP protein content was determined by Western blotting with an anti-FLIP antibody. (B) Human dendritic cells were either nontreated (left lane) or incubated with TNF (40 ng/ml) or LPS (10 μg/ml) for 24 h and analyzed by immunoblot assay for the expression of FLIP and TRAF1.