Spontaneous activity of caspase-3 in B-CLL cells is extremely low compared with acute-leukemia B cells (B-ALL) and B cells of healthy individuals immortalized with EBV (B-EBV).

The activity of caspase-3 was measured as in “Patients, materials, and methods” and the results indexed against these obtained for B-CLL cells. Bars show mean indexed values ± SD of 3 separate experiments. Statistically significant differences between the caspase-3 activities are marked * for P < .05 and ** forP < .001.