Cell expression of molecules known to be involved in apoptosis.

Culture day 7 cells were incubated as indicated in the legend of Figure5. (A) Flow cytometry analysis of Bcl-2 and Fas (CD95) expression; open histograms: labeling with the irrelevant mAb; shaded histograms: staining by the relevant mAb; data are from 1 experiment of 7 (Bcl-2) or 2 (Fas). (B) Assay of caspase-3 activity in cells: cell lysates were incubated for 10 hours with Ac-DEVD-pNa, the cleavage of which was assessed at 405 nm; data are from 1 experiment of 3.