Figure 4.

Role of death receptor signaling in ER stress-induced cell death. (A and B) casp9^−/− MEFs were pretreated with 50 ng/mL of TNF blocking antibody, 100 ng/mL of FAS:Fc or 500 ng/mL of TNFS10 blocking antibody for 1 h. For the next 24 h cells were treated with 0.5 μM of Tg (C) or 0.5 μg/ml Tm (D) and cell death estimated by propidium iodide staining. Protein samples from the same treatments were also harvested and expression of cleaved CASP8 was evaluated by protein gel blot (E). Actin was used as a loading control. Results are representative of at least 3 independent experiments. Error bars represent the mean ± SD.