Enrichment and Generation of MLL-AF9 Leukemia

All animal experiments were conducted with an Institutional Animal Care and Use Committee–approved protocol. Mouse MLL-AF9 leukemias in a dsRed transgenic background (6051; The Jackson Laboratory) were generated as previously described (Miller et al., 2013 (link)). To enrich for LSCs, femurs and tibias from leukemic mice were first harvested, crushed, and filtered, and red blood cells were lysed using lysis buffer (BD). Then BM cells were stained with APC-conjugated anti–c-Kit (clone 2B8; eBioscience) and dsRed⁺c-Kit^high cells (20% high) were sorted (FACSAria II; BD). MLL-AF9–driven Tp53^−/− leukemias were generated from c-Kit–enriched BM cells from Tp53^−/− mice (002101; The Jackson Laboratory).