FIG. 1.
Bcl-xL can protect 2B4 cells from apoptosis induced by TNF-α. (A) Bcl-xL protein levels in 2B4-transfected cells were detected by Western blot analysis. The results for one control transfected clone (neo) and two Bcl-xL-transfected clones (Xl c.5 and Xl c.10) are presented. (B) Viability assay (PI exclusion) of the clones at 36 h following treatment. Cells were either left untreated or treated with TNF-α in the presence or absence of the caspase inhibitor zVAD-fmk (200 μM). (C) Survival assay as described in panel B for cells treated with TNF-α in the presence of increasing concentrations of zVAD-fmk. (D) Kinetics of cell death. Cells were treated with TNF-α, and viability was determined by PI exclusion at the indicated time points.