利用诱导性多能干细胞技术体外扩增造血干/祖细胞的初步研究

In vitro expansion hematopoietic/progenitor stem cells by directed differentiation of induced pluripotent stem cells

目的 利用诱导性多能干细胞技术体外扩增造血干/祖细胞.方法 利用非整合型载体,将四个转录因子：Sox2、Klf4、Oct4和c-Myc导入脐血来源的造血干/祖细胞（CD34＋细胞）重编程获得诱导性多能干细胞（iPSCs）,再利用与小鼠骨髓基质细胞OP9共培养法将其定向分化成CD34＋造血干/祖细胞.借助iPSCs可以在体外无限传代、大量扩增的特点,实现体外保存及大量扩增造血干/祖细胞的目的.结果 脐血CD34＋细胞可以在体外重编程为非整合型iPSCs,并能够高效定向分化成为CD34＋细胞,其分化效率比胚胎干细胞（ESCs）有显著提高.结论 利用诱导性多能干细胞技术体外大量扩增脐血造血干/祖细胞是一个可行的方案,具有良好的应用前景.

Objective Expansion hematopoietic/progenitor stem cells by directed differentiation of induced pluripotent stem cells which induced from human cord blood hematopoietic stem cells.Methods Using episomal vectors of Sox2,Klf4,Oct4 and c-Myc to generate induced pluripotent stem cells from cord blood hematopoietic stem cells,we established integration-free iPSCs.And then we induced these cells differentiated into hematopoietic cells based on OP9 cells system in vitro.Result By examining CD34 positive cells,we found compared human ES cell line with cord blood sourced iPS cells could be differentiated into hematopoietic cells more efficiently.Conclusion A highly efficient method for expansion hematopoietic stem cells in vitro is successfully established,which is useable in clinical study.