Similar to IL-17A deficiency, anti-IL-17A treatment reduced the number of B220dim CD19+ cells (Fig. 3l) and Ki-67+ leukemia cells (Fig. 3m) in the BM, spleens, LNs, and PB of recipients, leading to a decrease in the death of B-ALL mice (Fig. 3n). This evidence concerns the gene IL17A and leukemia.