Effects of lentivirus-mediated RNAi on colony-formation of normal and CML CD34⁺ cells. (A) The diagram shows the relative ratio of RFP⁺ colonies under low as compared to high cytokine stimulation (IL-3 + GM-CSF) for normal (left) and CML (right) CD34⁺ progenitor cells. (B) The diagram shows the relative ratio of RFP⁺ colonies under low as compared to high cytokine stimulation (SCF + G-CSF + TPO) for normal (left) and CML (right) CD34⁺ progenitor cells as described. The specific RNAi target is indicated on top of each bar. Controls include GL4 and GFP shRNAs.