干细胞生长因子协同血小板生成素体外扩增脐血巨核前体细胞的研究

Studies on expansion of megakaryocytic progenitor cells from human cord blood CD34^+ cells in presence of stem cell factor combined synergistically with thrombopoietin in vitro

目的探讨在干细胞生长因子(SCF)和血小板生成素(TPO)组合作用下,人脐血CD34^+细胞体外扩增为巨核前体细胞的效果。方法采用经免疫磁珠纯化系统收集的人脐血CD34^+细胞与SCF+TPO组合体外培养,研究该组合对巨核前体细胞的扩增效果。结果在SCF和TPO组合的作用下,脐血CD34^+细胞(6例)显著地向巨核前体细胞(CD61+CD41^+细胞)扩增。CD61^+CD41^+细胞构成比在培养第7天达到峰值(15．57±4．95)％,第14天为(9．06±2．72)％；存第14天,CD61^-CD41^+细胞总数和巨核系细胞集落形成单位(CFU- MK)达到高峰,为较理想的培养时间。经过体外扩增,总细胞数、CD34^+细胞数、CD61^+CD41^+细胞和CFU-MK均显著增加。结论在SCF和TPO组合的作用下,脐血CD34^+细胞可有效地扩增为巨核前体细胞。

Objective This study focuses on the effects of stem cell factor （SCF） in combination with thrombopoietin （TPO） synergistically on expansion of magakaryoeyte progenitor cells by euhuring CD34^＋ cells derived from human cord blood in vitro. Methods Mononuclear cells （MNC） were separated from human umbilical cord blood samples （n = 6）; and CD34^＋ stem cells and progenitor cells were purified by using immunomagnetie beads, the number of nucleated cells, CD34^＋ cells, CD34^＋ CD38 cells, CD41^＋ CD61^＋ cells and megakaryocyte colonyforming units （CFU-MK） were evaluated 7, 14 and 21 th days after culture, the effects of SCF in synergistic combination with TPO were investigated on expansion of megakaryocytic progenitors in vitro. Results Enriched CD34^＋ stem and progenitor cells derived from cord blood were significantly expanded in the presence of SCF when synergistically combined with TPO. Expansion ratios of CD41^ ＋ CD61^ ＋ cells were respectively 15.57 % ± 4.95 % at 7th days, and 9.06%±2.72% at 14th days after culture. The top expansion of total CD41^＋ CD61^＋ cells as well as CFU- MK reached the peak at 14th days. There were overall increases of nucleated cells, CD34^＋ cells, CD34^＋ CD38^- cells, and CD41^＋ CD61^＋ cells and CFU-MK. Conclusion SCF combined with TPO can promote the expansion of megakaryoeyrie progenitors from cord blood CD34^＋ -enriched cells significantly in vitro, and the optimal culture duration for the cell expansion appears to be 14 days.