Prevention of CML development by the CCR5 receptor antagonist MVC. WT donor-derived LICs were subjected to the CML model. (A) MVC or vehicle was administered by oral gavage every 2 days from day 1 to 21 after LIC transplantation at a dose of 30 mg/kg body weight. Beginning 2 weeks after BM transplantation, the numbers of WBCs were determined weekly. Leukemia-free survival rates were determined (MVC, n = 6; control, n = 10). Mice that died of leukemia or those in which the WBC count reached 15 000 cells per μL were diagnosed with leukemia. *P < .05 by the log-rank test. The numbers of WBCs in PB (B), SP weights (C), or proportion of GFP⁺KLS⁺ LICs in the tibial BMs (D) were determined (C, D, 3 weeks). Each symbol represents an individual mouse (MVC, n = 6; control, n = 5). **P < .01; N.S., no significant difference by the Mann-Whitney U test.