With this limitation, clinical studies focused on CD33, CD123, and CD371 (CLL-1/Cec12), which show sufficient differential expression on AML and hematopoietic cells, and other potential targets, such as CD38, FLT3, CD56, CD30, CD7, and CD25, are under investigation (Figure 3). Here, FLT3 is linked to acute myeloid leukemia.