Recently, various immunotherapies were FDA-approved for ALL: Blinatumomab, a CD19 × CD3 bispecific mAb, Inotuzumab ozogamicin, a CD22-targeting ADC, and Tisagenlecleucel, an anti-CD19 CAR T cell product, have remarkably improved the outcome of r/r B-ALL patients [10,11,12,28]. This evidence concerns the gene CD22 and acute lymphoblastic leukemia.