Figure 3.

The pan-caspase inhibitor zVAD-fmk, does not significantly inhibit CTL apoptosis. A. P14 splenocytes, stimulated as in Fig. 1 were restimulated with 5 μg/ml of plate-bound αCD3 antibody for 6 hr in the presence or absence of 100 μm zVAD-fmk. The cells were then stained with αCD8 Cy5 and AnnexinV-PE and analysed by flow cytometry after gating on CD8⁺ cells. (b) NIH3T3 cells were either cultured without treatment or treated with 1 μm Staurosporine for 2 hr in the presence or absence of 100 μm zVAD-fmk. The cells were then lysed and the lysates analyzed by Western blot for caspase 3 substrate, PARP cleavage using a monoclonal antibody that recognizes cleaved but not native PARP.