CD19 and neoplasm: Sca1-ETV6-RUNX1 + Kdm5cf/wt + Sca1-Cre B-ALLs displayed clonal immature BCR rearrangement (Supplementary Figure 10), and FACS analysis revealed a CD19+B220+IgM– cell surface phenotype of the tumor cells in BM, PB, and spleen (Supplementary Figure 11) with the capability to infiltrate other tissues like the spleen, liver, and small intestine (Figure 5D and Supplementary Figure 12).