Costimulation of Murine Osteoblasts with Interferon-γ and Tumor Necrosis Factor-α Induces Apoptosis through Downregulation of Bcl-2 and Release of Cytochrome c from Mitochondria

Figure 4

Time-dependent activation of caspases in MC3T3-E1 cells costimulated with IFNγ and TNFα. Cells were seeded in 10 cm dishes, incubated for 5 days to form a confluent monolayer, and costimulated with 10 ng/ml IFNγ and 5 ng/ml TNFα. Caspase activity in a 50 μg total cell lysate was monitored over time against appropriate synthetic chromogenic substrates. Relative caspase activity was calculated and compared with caspase activity in untreated cells. Data represent the mean ± SEM of five independent experiments. versus the 3 h time point by one-way ANOVA.

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