Flk1⁺CD31^–CD34^– cells from patients with CML give rise to hematopoietic cells in NOD/SCID mice. (A) Immunophenotype of BM specimen at day 62 showing predominant engraftment of myeloid cells with lower level of CD3 and CD19 cells. Besides, the engraftment of primitive human cells was confirmed in the BM of recipient mice by detection of CD34. (B) Human Y chromosome was detected by FISH (red signal) in the cells of bone marrow from mice that received a transplant (original magnification × 400). A 40×/0.65 objective lens was used.