Single T-ALL cells can be efficiently transplanted into non-IR CG1 recipient. Transplant recipient fish receiving 1 FACS-sorted dsRED⁺ T-ALL cell at 20 (A,D), 30 (B,E), and 45 days after transplantation (C,F). One representative animal engrafted T-ALL by 20 days (A-C), whereas one never developed leukemia (D-F). Images photographed at 7.0×. All panels are merged images of fluorescent and brightfield photographs.