PSMB10 and Splenomegaly: Mice receiving Psmb10−/− MA9 bone marrow cells as the 1st recipients, combined with chemotherapy, exhibited longer survival compared to those receiving Psmb10+/+ MA9 cells (34 days vs 19 days, p = 0.0007; Fig. 4G), and the Psmb10−/− MA9 BM cells 1st recipient mice combined with chemotherapy had lower numbers of GFP+ leukemia cells in the BM, PB and spleen and less severe splenomegaly than did the Psmb10+/+ MA9 1st recipient mice (Fig. 4H, and Supplementary Fig. S3D and E).