EGM and EGM2 media support the survival of leukemic stem cells. (A-C) Primary AML cells were thawed and plated at 1 × 106 cells/mL in indicated medium. Viable cell number was counted by trypan blue exclusion. (D) Primary AML cells were thawed and allowed to recover for 2 hours. Viable cells were counted, and 5 million cells per animal were injected immediately (day 0) or after 1 to 2 days of incubation in EGM2 medium. No adjustments to cell numbers were made after incubation. Cells were injected into sublethally irradiated NOD/SCID mice, and animals were monitored for 7 weeks. Animals were humanely killed and bilateral femurs were harvested. Percentage shown is average of human CD45+/CD33+ cells in the bone marrow. Each dot indicates 1 animal, and the central bar is the mean of the average engraftment.