Prophylactic B-I09 administration does not impair the GVL effect. Lethally irradiated BALB/c recipients were transplanted with TCD-BM from B10.D2 donors with (n = 20) or without (n = 13) whole splenocytes. Mice were also cotransplanted with either no blast crisis chronic myeloid leukemia cells (BC-CML) (n = 4) or 1 × 10⁶ BC-CML splenocytes (n = 29). Groups subsequently either received no treatment (n = 4), received daily IP injection of DMSO vehicle (n = 16), or received 25 mg/kg B-I09 (n = 13) on day 0 and continued for 3 weeks. Peripheral blood was collected and analyzed for GFP⁺CD11b⁺ expressing BC-CML cells via flow cytometry (A) periodically after transplant until day 35 and is shown as a time course of GFP⁺CD11b⁺ cells in each group (B). On day 60, mice were killed, and splenocytes were analyzed for the presence of BC-CML cells indicated by GFP⁺CD11b⁺ expression (C). Flow cytometry plot from panel A is representative of 2 replicate experiments. Data from panels B and C are pooled from 2 replicate experiments.