利用IL－3／GM－CSF融合蛋白（PIXY－321）扩增脐血造血细胞方法的初步建立

PRELIMINARY ESTABLISHMENT OF EXPANSION METHOD FOR CD34+ CELLS FROM UMBILICAL CORD BLOOD BY USING IL 3/GM CSF FUSION PROTEIN(PIXY 321)

利用单克隆抗体免疫磁珠吸附方法分离脐血ＣＤ３４＋细胞，并观察了ＩＬ３／ＧＭＣＳＦ融合蛋白（ＰＩＸＹ３２１）对脐血ＣＤ３４＋细胞的刺激作用。ＰＩＸＹ３２１对脐血ＣＤ３４＋细胞扩增作用大于ＩＬ３和ＧＭＣＳＦ单独及联合应用。在液体培养条件下，每毫升２０ｎｇＰＩＸＹ３２１可有效地扩增脐血造血祖细胞，适宜扩增时间为５－８天，扩增后造血祖细胞的数量可达扩增前的８－１０倍，从而初步建立了一种简单可行的脐血造血细胞扩增方法。

Using high gradient magentic cell sorting (MACS)system, we had isolated CD34+hematopoietic progenitor cells from umbilical cord blood and observed stimulating effect of IL 3/GM CSF fusion protein (PIXY 321) on the growth of CD34+ cells. PIXY 321 has a higher stimulating effect than IL 3 and GM CSF alone or in combination. 8-10 fold expansion of hematopoietic progenitor cells could be achieved in liquid culture system containing PIXY 321 at a concentration of 20ng/ml, the optimal expansion time was 5-8 days. Thus, a simple and effective expansion method for hematopoietic progenitor cells from umbilical cord blood has been set up preliminarily.