T-ALLs from CG1-strain zebrafish engraft into non-IR CG1-strain recipients. GFP-labeled T-ALLs were isolated from primary leukemic fish, and 103 FACS-sorted GFP-labeled leukemia cells were transplanted into non-IR CG1- and AB-strain animals (A-C and G-I, respectively) or IR AB-strain fish (D-F). Transplant fish were scored for engraftment at 10, 20, and 30 days after transplantation. Panels are merged images of fluorescent and brightfield photographs. The engraftment kinetics differ greatly when T-ALLs are introduced into CG1 (J) or IR AB-strain zebrafish (AB + IR; K). Percent engraftment is the percentage of recipient animals that have visibly engrafted T-ALL at each time point. Panels J and K are combined data from 3 independent experiments (n = 238 transplants total). The raw data for this experiment are available in supplemental Table 2.