CD38 and acute myeloid leukemia: Next, flow cytometric immunophenotyping was performed in bithionol-treated KG-1a cells after 48 h of incubation with the myeloid lineage markers CD13 [26] and CD33 [27] and the AML progenitor/stem markers CD34 [28], CD38 [28], and CD123 [29] (Fig. 2).