The caspase-2 permeant inhibitor Z-VDVAD-fmk prevents Fas-induced apoptosis of parental U937 and Jurkat cells.

Z-VDVAD (50 μM) was added to cell culture in combination with CH11 anti-Fas Abs (50 ng/mL), in the presence (U937) or absence (Jurkat) of CHX (0.8 μg/mL) for 3.5 hours. (A) Apoptosis was determined by Hoechst 33342 staining of nuclear chromatin (mean ± SD of 3 experiments). (B) DEVDase and IETDase activities were measured as initial velocities. Results were related to those obtained in untreated cells (one representative of 2 experiments).