GM-CSF, IL-3, SF, and TPO increase the intracellular level of ROS in hematopoietic cell lines. (A through C) The relative levels of ROS were measured in starved cells (dotted line) and in growth factor-treated cells (straight line) as indicated using 2’, 7’-dichloro-fluorescin-diacetate (bottom panel) or the autofluorescence of these cells was measured without fluorochrome (top panel). (A) MO7e cells were treated with either GM-CSF (10 ng/mL), IL-3 (10 ng/mL), SF (20 ng/mL), or TPO (100 ng/mL) for 18 hours. (B) TF1 cells were treated with either GM-CSF (10 ng/mL) or IL-3 (10 ng/mL) for 18 hours. (C) 32Dcl3 cells were treated with IL-3 (10 ng/mL) for 18 hours. (D) The increase in relative levels of ROS was measured in MO7e cells stimulated for 0 to 18 hours with 20 ng/mL GM-CSF.