Actions of anti-Fas antibodies on B-CLL killing.

(A) MTT assay of a B-CLL sample incubated with no antibody (open bars), 50 ng/mL anti-Fas IgM (hatched bars), or 250 ng/mL ZB4 (striped bars) in addition to cytotoxic agents. The absorbance of MTT reduced by the 24-hour control was set at 1, and the viability of treated cells was compared to this value. (B) Western blot of the processing of PARP to p85 PARP in B-CLL cells from same patient after treatment with Chl, Flu, or γ irradiation with or without 50 ng/mL anti-Fas IgM (F) or 250 ng/mL ZB4 (Z).