CD33 and acute myeloid leukemia: Other studies have further demonstrated that it improves CAR-T cell therapy safety through the use of iCasp9 in CD33-CAR-T cell against AML (183), interleukin-1 receptor accessory protein (IL-1RAP)-CAR-T cell against chronic myeloid leukemia (184) and CD19-CAR-T cell against various hematological malignancies (98).