Expression of FasL protein. Flow cytometry analysis of (A) cytoplasmic and (B) membrane bound FasL of leukemic cells from P2 (CML), P12 (CML), and P17 (AML4) individuals. In (A), cytoplasmic FasL (solid peak) is detected in patients (P2) as compared to isotype control (dashed line). In (B), the percentage of leukemic cells expressing membrane bound FasL is shown.