ARG1 and chronic myelogenous leukemia, BCR-ABL1 positive: We next quantified granulocytic (Gr) MDSCs, defined as CD45+CD11bbrightCD33dimCD15+Arg1+ cells, and monocytic-like (Mo) MDSCs, defined as CD45+CD11bbrightCD33brightCD15negArg1neg cells, in CML patients and controls.