FIG. 3.
Bcl-xL blocks ROS induction in TNF-α-treated cells but has no ROS scavenging activity. (A) Control cells (2B4/neo) and Bcl-xL-expressing cells (2B4/Xl c.5 and 2B4/Xl c.10) were either left untreated or treated with TNF-α. At the indicated time points, the cells were stained with DCFH-DA and PI, and ROS levels were analyzed as in the experiment in Fig. 2A. (B) DCFH oxidation. Untreated cells were incubated in the presence of DCFH-DA (added at time zero), and DCFH oxidation was analyzed by FACS analysis at the indicated time points. Mean fluorescence units (F.U.) represent the level of DCFH oxidation at each time point. (C) Cells were incubated with DCFH-DA for 30 min, and DCFH oxidation was measured by FACS analysis in a continuous assay. After 2 min, H2O2 (50 nmol/105 cells) was added (arrow), and DCFH oxidation was measured for a further 30 min.