The number of CFU Mix and HPP CFC generated from the culture system containing hDll 1 ext was 1.5 times of that from the control. In conclusion, the recombinant hDll 1 ext promotes the expansion of primitive hematopoietic progenitors.

• 含hDll 1ext组中CFU Mix和HPP CFC数量是对照组的 1.；5倍；结论 :重组的hDll 1ext对原始的造血祖细胞具有扩增作用