In vivo treatment with TRAIL prolongs life in animals engrafted with pre-B ALL xenograft cells. NSG mice were injected with 5 × 104 ALL-54 cells and treated on days 5 to 9 and days 12 to 16 (10 doses) with 7.5 mg/kg TRAIL, vehicle, or mutant C230S-TRAIL by intravenous bolus injection. Five mice were treated with TRAIL; 6 mice each were treated with vehicle or the TRAIL mutant C230S. (A) Survival curve. The P value is for the log-rank test. p.i. indicates postinjection. (B) For secondary transplantations, 106 leukemia splenic cells of 1 mouse treated with vehicle and 1 diseased mouse treated with TRAIL were injected into 2 mice each. Secondary transplant recipients were monitored for engraftment as described in Figure 1D and E. The mean time to overt leukemia is shown together with the SD from the 2 mice.
