Time-dependent apoptosis. Granulocytes underwent spontaneous apoptosis by incubation for up to 24 hours in the absence of anti-FAS MoAb. (A) Twenty healthy volunteers (○), and 11 patients with PNH (•). (B) Six PNH patients with a high proportion (more than 90%) of CD59⁻ granulocytes (•), and three PNH patients with a low proportion (less than 10%) of such cells (▴). Data are means ± SD of duplicate samples.