Transplantable, preleukemic NUP98-HOX cells can be converted into leukemic cells by wt-Flt3. (A) Survival curve of mice given transplants of ND13 or ND13/Flt3 cells. (B) Survival curve of mice given transplants of NA10 or NA10/Flt3 cells. (C) FACS analysis of GFP (ND13/NA10) and YFP (Flt3) expression in leukemic bm cells (2 representative profiles shown). (D) Southern blot analysis of genomic DNA harvested from the bm of ND13/Flt3 leukemic mice and probed with an Flt3-specific probe. Lanes 1 and 2 show ND13/Flt3 transplants 1 and 2, respectively; Lane 3, C57-negative control mouse. Arrows denote endogenous Flt3. (E) Southern blot analysis of genomic DNA harvested from bm of NA10/Flt3 leukemic mice and probed with an Flt3-specific probe. Lanes 1 and 2 show NA10/Flt3 transplants 1 and 2, respectively; Lane 3, C57-negative control mouse. (F-G) In vitro dose-response growth curves where bm cells harvested from diseased NA10/Flt3 or ND13/Flt3 mice were grown in 10% FBS and 0, 10, or 50 ng/mL FL in the presence or absence of Flt3 inhibitor AG1295 for a period of 5 days. The error bars represent the standard deviation from 3 independent experiments.