Normal BM MNC (A-D) and representative data of 16 AML cells (E-T) of two-color flow cytometric analysis of Fas expression and CD34 expression. (A) Two isotypic control antibodies, (B) FITC control antibody and PE-conjugated anti-CD34 MoAb, (C) FITC-conjugated anti-Fas MoAb and PE control antibody, (D-T) FITC-conjugated anti-Fas MoAb and PE-conjugated anti-CD34 MoAb. In contrast to normal BM MNC (D) whose CD34⁺ cells are Fas⁻, some CD34⁺ cell in AML express Fas. Various patterns of distribution are shown; the single population group (SP, E-L), the two-population group (TP, M-N), and the wide distributed group (WD, Q-T).