BCR-ABL donor cells increase within the LSK compartment on reinduction. (A) Analyses of LSK composition in reinduced mice showed doubling of LSK cells in the spleen of transplanted recipients of dtg, but not stg BM cells, on reinduction. (B) FACS analysis of donor (CD45.1+) and recipient (CD45.2+) cells within the LSK compartment. (C) Increase of dtg donor cells in LSK and progenitor cells was observed in BM and spleen of dtg recipients (mean ± SD); n = 3 per group. *P < .05. (D) Wild-type recipients were transplanted with 2 × 106 BM cells of noninduced dtg or stg donors. Expression of BCR-ABL was induced by removal of tetracycline from the drinking water directly after transplantation. Mice were treated twice daily, using imatinib or water for 4 weeks. WBCs and percentages of granulocytes (Gr-1+/CD11b+) in the PB were analyzed before treatment, during treatment (2 weeks and 4 weeks), and 2 weeks after completion of imatinib treatment. Error bars represent the mean ± SD; n(stg/dtg) before treatment = 3/3; n(stg/dtg IM or stg/dtg water) during treatment = (4/6/3/5); n(stg/dtg) 2 weeks after treatment = (4/4). *P < .05.
