IGSF9 level is detected by flow cytometry. (A-E) IGSF9 levels are detected by flow cytometry in T cells, B cells, and myeloid cells from healthy donors (n = 10), CD33⁺/CD13⁺ leukemia cells (n = 27), CD34⁺/CD117⁺ leukemia stem cells (n = 15), umbilical cord blood (n = 5), and AML cell lines including THP-1, MV4-11, Molm13, and U937 cells. APC, allophycocyanin; FITC, fluorescein isothiocyanate; PBMC, peripheral blood mononuclear cell.