MLL-GPHN immortalized cells cause leukemia in vivo. (A) Survival curves of mice (n ≥ 10) injected with immortalized cells by MLL-GPHN full-length, MLL-GPHN ex 14, or mock-injected (control) mice. (B) May-Grünwald/Giemsa–stained cells from bone marrow of injected mice (original magnification, × 600). Massive infiltration of leukemic cells in bone marrow is observed, which also appears in peripheral blood. (C) Fluorescence-activated cell sorter analysis of leukemic cells. Myeloid lineage-specific markers are apparent in most of the mice, although lymphoid lineage-specific markers are detected in some mice.