Apoptosis of CD34⁺ cells from MDS-BM. CD34⁺ cells were isolated from the BM of patients with MDS (CMMoL, A and D; RA, B and E) and a healthy donor (C, F ). Cells were then treated and analyzed as described in the legend to Fig 7. The population of viable cells (R1) after treatment was 39%, 51%, and 8% in the patients (D, E) and the healthy control (F ), respectively. (A, B, and C) Cells before treatment. A second experiment with cells from three other patients with MDS and three healthy donors gave similar results.