Figure 1.

Ex vivo analysis of humanized mouse positive (Ph⁺) acute lymphoblastic leukemia cells. (a) Leukemic spleen cells were CD34 positively selected with MACS column. CD34⁺ cells were stained with Hoechst, PyroninY and CD38-allophycocyanin (APC). Cells including CD34⁻ population that had flowed through the column were stained with Hoechst, PyroninY and CD34-APC. (b) Leukemic spleen cells were ex vivo cultured with cytokines and treated with or without imatinib (IM) for 48 h. Human CD45⁺ propidium iodide (PI)⁻ Annexin-V⁻ viable population was analyzed for CD34 and CD38 distribution. Panels show a representative experiment. (c) After treated with IM for 48 h, CD34⁺ cells were positively selected with MACS column, and stained with Hoechst, PyroninY and CD38-APC. Cells including CD34⁻ population that had flowed through the column were stained with Hoechst, PyroninY and CD34-APC. Graphs show the number of forward scatter/side scatter gated G₀ cells in each CD34/CD38 sub-population, each relative to the untreated control. Bars indicate mean±s.d. values of three independent experiments (^*P=0.03 between control and IM 3 μ for CD34⁺ CD38⁻, and ^**P=0.02 between control and IM 3 μ for CD34⁻, by one-way analysis of variance followed by Bonferroni). (d) CD34/CD38 sorted populations were treated with or without IM 3 μ for 6 h. Expression of BCR-ABL and phosphorylation of BCR-ABL and CrkL in each population was examined by western blotting analysis.