Figure 2. Caspase is critical for the radiation-induced exposure of PS.

cfPac-1 cells were irradiated at 10 Gy in the presence or absence of 10 μM Z-VAD-fmk, Sigma (St. Louis, MO, USA). 24 hr. later the cells were assessed for Annexin V binding as in Figure 1. ^**p < 0.01, NS = not significantly different from control.