Development of MPD in Cbfb-CKO mice. (A) Splenocytes from 6- to 8-week-old Vav1-iCre⁺Cbfb^F/+ (Het) and Vav1-iCre⁺Cbfb^F/F (CKO) mice were analyzed for expression of CD11b, Ly6C, and Ly6G. Percentages of CD11b⁺ cells in total splenocytes and Ly6C^hiLy6G^– monocytes in CD11b⁺ splenocytes are shown. (B) B220^–CD11b^– BM cells from 6- to 8-week-old Vav1-iCre⁺Cbfb^F/+ and Vav1-iCre⁺Cbfb^F/F mice were analyzed for c-kit, Sca1, and CD16/32 expression. GMP, MPP, and CD16/32⁺ MPP (bottom panels) percentages in c-kit^hi cells (top panels) are shown. Statistical analysis from 6 to 9 mice in 6- to 8-week-old and 12- to 16-week-old groups is shown in panels D to G as mean and standard deviation. (C) c-kit and CD16/32 expression in total splenocytes (top) and peripheral blood WBCs (bottom) in 12- to 16-week-old Vav1-iCre⁺Cbfb^F/+ (Het, left) and Vav1-iCre⁺Cbfb^F/F (CKO, right) mice. Percentages of c-kit⁺CD16/32⁺ GMPs are shown with rectangular gates (n = 3, peripheral blood; and n = 6, splenocytes). (H) Hematoxylin and eosin staining of formalin-fixed liver sections from 6- to 8- and 12- to 16-week-old Vav1-iCre⁺Cbfb^F/+ (Het) and Vav1-iCre⁺Cbfb^F/F (CKO) mice. Clusters of infiltrating cells are surrounded by dotted lines. P, portal triad; CV, central vein. Images are representative of 3 mice for each genotype and age. (I) Clonal lineage potential of BM Lin^–c-kit⁺Sca1⁺CD135^–CD150⁺ cells from Cbfb-CKO (CKO) and control mice (Het) determined by a single cell culture (n = 2). SSC, side scatter. *P < .05; **P < .01; ***P < .001.