磁力搅拌悬浮培养大规模扩增脐血造血祖细胞

为了利用磁力搅拌悬浮培养装置大规模体外扩增脐血造血祖细胞，从脐血分离单个核细胞，以无血清培养基stemspan添加干细胞因子、FLT-3配基及血小板生成素为培养体系进行培养。先研究磁场（25和50mT）对静态扩增培养的造血祖细胞生长和集落形成能力的影响，再研究磁力搅拌悬浮大规模培养对造血细胞总数扩增、造血集落形成和表面分子标志表达变化。结果表明，在0，25和50mT磁场组和磁转子组，细胞总数扩增倍数和造血集落形成数在各组间均无明显区别（P〉0．05）。经过7天的扩增培养，磁力搅拌悬浮大规模培养细胞总数扩增倍数为2．8±0．45，高于静态培养细胞总数扩增倍数（2．1±0．48）（P〈0．01）；磁力搅拌悬浮培养组形成的红系集落数（1983．5±582．6）、粒-巨噬细胞集落数（186．4±62．7）明显高于静态培养形成的相应的造血集落数（分别为1396．2±425．7和136．5±40．8）（P均〈0．05）：磁力搅拌悬浮扩增后造血干细胞（CD34^＋、CD34^＋／CD38^-或CD133^＋）比例分别为（0.9±0．34）％、（0．7±0．21）％和（1．1±0．35）％，低于静态培养的干细胞比例分别为（1．4±0．35）％、（1．2±0．34）％和（1．6±0．68％）]（P均〈0．05）；但是，归巢相关分子CD184和CD62L高于静态扩增培养．．结论：磁力搅拌悬浮装置可能有利于脐血造血祖细胞规模扩增，本研究结果还有待于动物实验及临床移植试验进一步验证.

Large Scale Expansion of Hematopoietic Progenitor Cells from Umbilical Cord Blood by Magnet Stirred Culture System

The aim of this study was to expand hematopoietic progenitor cells at large scale by magnet stirred culture system. Mononuclear cell from umbilical cord blood were cultured in serum-free medium with stem cell factor, FIT-3 ligand and thrombopoietin. Firstly, the role of magnet on cell growth and colony-forming was studied by static culture on 0, 25 and 50 mT. Then the expansion multiple of cells, colony-forming and expression of surface markers were studied in magnet stirred culture by cell counting, colony-forming assay and flow cytometry. The results indicated that there was no difference in multiple of total cell expansion and numbers of hematopoietic colonies between 0, 25 and 50 mT groups and spinner groups (all p > 0.05). After 7 day cultures, the multiple of total cell expansion in magnet stirred culture was higher than that in static culture (p < 0.01). The numbers of CFU-GM (colony-forming unit-granulocyte/macrophage) and CFU-E (erythroid colony forming unit) in magnet stirred culture were higher than those in static culture, (p < 0.05). The primitive cells (CD34(+), CD34(+)/CD38(-) or CD133(+)) of the expanded cells in magnet stirred culture were less than those in static culture (p < 0.05). However, the CD184(+) or CD62L(+) expanded cells were more than that in static culture (p < 0.05). It is concluded that magnet stirred culture favors the expansion of hematopoietic progenitor cells. The results will be finally confirmed in further in vivo experiments and clinical applications.