IK6 enhances basophil production from primitive CP-CML cells at multiple stages of differentiation. (A) Experimental design used to test the effect of IK6 on the CFCs produced from 2 different subsets of CD34⁺CD38⁺ cells after 0 to 15 days in the same suspension culture conditions used for lentiviral gene transfer. (B) Numbers of colonies produced from IK6- and control-transduced CD34⁺CD38⁺CD133^low cells (enriched for basophil and eosinophil progenitors) obtained by FACS from 3 CP-CML patients and a pool of 3 normal BM samples and cultured as described in panel A. The inset shows a representative cytospin of cells in the colonies. (C) Numbers of colonies produced from IK6- and control-transduced CD34⁺CD38⁺FLT3⁺CD45RA⁺ cells (enriched for neutrophil/monocyte progenitors) obtained by FACS from 2 CP-CML patients, as described in panel A. The inset shows a representative cytospin of cells in the colonies.