Flow cytometric analysis of B-CLL cells.

(A) Analysis of cell-surface Fas expression in a representative B-CLL sample. R is the ratio of the MedCF of anti-Fas IgG FITC antibody-stained cells (open histogram) against IgG FITC isotype control-stained cells (shaded histogram). (B) Analysis of multiple B-CLL samples after 24-hour incubation with chlorambucil or fludarabine or after γ irradiation.