CML-like disease is transplantable using LSK or ufBM cells. For transplantation experiments, BM cells of 3-week–induced SCLtTA/BCR-ABL (dtg) or single transgenic (stg) control donor mice were used (n = 4 each). (A) Recipients of 1200 FACS-sorted LSK cells showed signs of disease 11 weeks after transplantation and were analyzed at that time point. Percentages of mature granulocytes (Gr-1⁺CD11b⁺), immature granulocytes (Gr-1^lowCD11b⁺), B cells (B220⁺), megakaryocytes (CD41⁺), and erythroid cells (Ter119⁺) were measured in BM and spleen. In addition, the percentage of T cells (CD3⁺) was measured in spleen. (B) Recipients of 1 × 10⁶ ufBM cells were moribund and thus analyzed 8 weeks after transplantation. FACS analysis was performed according to LSK transplanted mice in panel A above (stg n = 5, dtg n = 4). (C) Splenomegaly was more pronounced in mice transplanted with ufBM compared with LSK cells. (D) Histologic analyses of the spleen were performed using naphthyl acetate (chloro-)esterase (NACE)–stained slides and are shown at original magnifications of ×10 (insets) and ×40. Infiltration by myeloid cells as well as a disturbed lymph follicle architecture were evident in the spleen of recipients, transplanted with ufBM or LSK cells from dtg, but not control donors. All data are shown as mean ± SD. *P < .05.