Figure 4.

Expression of Fas receptor on PIGA^– and PIGA⁺ CD34 cells from four patients. Cells were stained for CD34, GPI-anchored CD59, and CD95 in three-color analyses. CD95 levels in patients’ nonmutated CD34⁺ cells (upper panels: a, c, e, and g) and patients’ PIGA-mutated CD34⁺ cells (lower panels: b, d, f, and h) are shown. As seen in the upper panels, CD95 levels on the nonmutated CD59⁺ cells were higher than on PIGA-mutated CD59^– cells in the same samples. For each patient, a total of 100,000 gated events was collected based on forward and side scatter and cells were analyzed gating on CD34 positivity and CD59 positivity or negativity. For each patient, about 200–400 events were recovered.