Other cell surface antigens that are expressed preferentially or even selectively on CD34+/CD38− AML LSC, but not (or only at trace amounts) on normal stem cells, include CD9, CD25, CD93, CD96, HLA-DR, and interleukin-1 receptor accessory protein (IL-1RAP) (Table 1) [35,37,40,41,42,43,44,45]. This evidence concerns the gene IL1RAP and acute myeloid leukemia.