Since Bcr-abl+ Lin−Sca1−ckit+/−CD34+CD38− bone marrow cells function as LSCs in murine chronic phase CML models, we studied these cells with or without ex vivo granulocyte differentiation with G-CSF [15, 16, 31]. This evidence concerns the gene CD38 and chronic myelogenous leukemia, BCR-ABL1 positive.