Fig. 2. Inhibition of TNF/CHX-mediated caspase-3 activation by Antp. HeLa cells were incubated with medium containing increasing concentrations of Antp for 30 minutes at 37°C. Then cells were washed and apoptosis was induced by stimulation with TNF-R1-specific mutant TNF (100 ng/ml) and CHX (2 µg/ml). (A) For measurements of caspase-3 activity cells were harvested 6 hours after the induction of apoptosis. The error bars represent the standard deviation of the mean of three independent experiments. (B) Determination of cell viability was performed 24 hours after TNF/CHX treatment using crystal violet staining.