In vivo generation of human CD34⁺ cells.

In this study, Lin⁻CD34^high or Lin⁻CD34⁻ cells (5 × 10⁴) were transplanted into the left tibia of NOD/SCID mice using the IBMI technique. After 12 weeks, the rates of CD45⁺ and CD34⁺ cells in the injected left tibiae and other bones (right tibia + 2 femurs + 2 humeri) were separately analyzed by flow cytometry. In these representative mice that received transplants of CD34⁺ SRCs and IBMI-CD34⁻ SRCs, both showed the marked repopulation with human CD45⁺ cells. Importantly, both SRCs generated the significant numbers of CD34⁺ cells not only at the site of injection, but also at the destinations of migration. The numbers in the quadrants define percentages of these cells.