The results indicated that the frequency of Th17 cells among peripheral blood mononuclear cells (PBMCs) increased progressively during BCR-ABL-induced B-ALL development (Fig. 1b and Supplementary Fig. 1i), but the proportion of CD4+ T cells in the PB of mice with BCR-ABL-driven B-ALL was similar to that in the PB of WT mice during B-ALL progression (Supplementary Fig. 1j). This evidence concerns the gene CD4 and precursor B-cell acute lymphoblastic leukemia.