Identification of SP and CD34^low/− cells in recipient bone marrow KSL cells.

(A) Hoechst dye efflux in various gates of KSL prepared from bone marrow of competitive LTRA recipients. Total KSL, GFP⁺Ly5.1⁺ KSL, and GFP⁻Ly5.1⁺ KSL from a representative recipient of HES-1Igv–transduced tester cells and competitor cells, and GFP⁺Ly5.1⁺ KSL from a representative recipient of GFPv-transduced tester cells and competitor cells were analyzed for staining for Hoechst 33342Blue and Hoechst 33342Red. (B) CD34 expression profile in various gates of KSL prepared from recipients of competitive LTRA. The same gates as panel A were used. To stain CD34 without FITC, PerCP-Cy5.5–labeled mouse CD34 antibody was used. This makes the fluorescence activated cell sorting (FACS) pattern different from that used for CD34⁻KSL sorting. (C) Evaluation of stem cell activity on secondary transplantation. At each time point, chimerism of donor-derived cells in recipient blood was plotted. Plots are shown as the mean ± SD of 4 animals.