Evi1-overexpressing cells express CD41. (A) Schematic representation of gene expression and FACS analysis. Murine c-kit⁺ BM cells were transduced with Evi1-GFP or mock-GFP for 2 days, and GFP⁺ cells were sorted and subjected to gene expression analysis. Evi1-GFP-transduced cells were seeded in cytokine-supplemented methylcellulose culture medium (MethoCult GF M3434 from StemCell Technologies, Vancouver, BC, Canada) and serially replated. FACS analysis was performed at the third replating. Three independent experiments were performed. (B) The messenger RNA (mRNA) expression of Evi1 (left) and Itga2b (right) was compared between Evi1-GFP- and mock-GFP-transduced murine BM cells. Expression levels relative to normal c-kit⁺ BM cells are presented. Error bars indicate standard deviation (SD; n = 3; *P < .05, Student t test). (C) Surface CD41 expression was analyzed by FACS. Cells were stained with a phycoerythrin (PE)-conjugated isotype control antibody or a PE-conjugated anti-CD41 antibody. Representative FACS data and a bar graph showing frequencies of CD41⁺ cells are presented. Error bars indicate SD (n = 3; ***P < .001, Student t test). (D-F) Expression analysis of CD41 in MLL-ENL-immortalized murine BM cells. (D) BM-MNCs isolated from 5-FU–treated mice were retrovirally transduced with MLL-ENL and immortalized by serially replating in semisolid culture. Four MLL-ENL-immortalized clones from 2 independent experiments were established. The mRNA expression levels of Evi1 (x-axis) and MLL-ENL (y-axis) are shown. Obviously, four MLL-ENL-transduced clones (closed circles) are divided into Evi1⁺ (n = 2) and Evi1⁻ (n = 2) clones as indicated. A closed triangle indicates normal c-kit⁺ BM cells. (E) Comparison of Itga2b expression levels between Evi1⁺ and Evi1⁻ clones. Expression levels relative to normal c-kit⁺ BM cells are presented. Error bars indicate SD. (F) Surface CD41 expression was analyzed by FACS. Evi1⁺ clones, but not Evi1⁻ clones, clearly expressed CD41.