CD33 and leukemia: Due to the high phenotype similarities between healthy and malignant HSPCs [34] and aiming to use the AdFITC-CAR T-cell diabody approach as both time-limited leukemia eliminating and non-genotoxic conditioning prior to subsequent HSPC-transplantation, we hypothesized that CD33 and CD117 could be highly suitable target antigens [35, 36].