Sorted CD14⁺ gp91^{phox +} mature malignant from FAB M4/M5 AML produce ROS. (A) A representative set of FACS plots of a FAB-M4 AML patient (patient 6) with 2 distinct myeloid populations, one immature blast population CD34⁺CD33⁻CD14⁻ (green) and one monocyte-like CD34⁻CD33⁺CD14⁺ (blue) population, is shown. (B,C) FACS-sorted mature CD14⁺ leukemic cells (blue) and immature CD34⁺ leukemic cells (green) were stimulated with PMA and assayed for ROS production. Panel B shows the kinetics of a representative experiment, and panel C shows total ROS production (n = 3, patients 5-7).