Elevated levels of ROS in the most primitive LSCs from CML-CP–like mice. BMCs were obtained from healthy (black bars) and CML-CP–like (gray bars) mice. (A) ROS were detected with DCFDA in HSCs/LSCs (Lin⁻c-Kit⁺Sca-1⁺) and HPCs/LPCs (Lin⁻c-Kit⁺Sca-1⁻) from 7 healthy (black bars) and 4 CML-CP–like (gray bars) animals. *P ≤ .001 in comparison with HSCs; and P < .05 in comparison with LPCs. (B) ROS were detected with DCFDA in BM-derived subpopulations of Lin⁻c-Kit⁺Sca-1⁺ cells from 2 healthy and 2 CML-CP–like mice: CD34⁻Flt3⁻ LT, CD34⁺Flt3⁻ ST, and CD34⁺Flt3⁺ MPPs. *P < .05 in comparison with healthy counterparts. (C) ROS were measured with DHE (left panel) and CC-1 (right panel) in Lin⁻c-Kit⁺Sca-1⁺CFSE^max quiescent cells from 7 and 4 normal, and 3 and 3 CML-CP–like mice, respectively. *P < .05 and **P < .005 in comparison with healthy counterparts.