二甲基亚砜联合羟乙基淀粉的非程控降温法冻存脐血造血干细胞研究

为了探索有效低温保存脐血造血干／祖细胞的冷冻保护剂和技术，进行了二种方法试验。第一种方法联合使用二甲基亚砜(DMSO)和羟乙基淀粉(HES)(分子量120000)作为冷冻保护剂并用非程控降温冷冻技术；第二种方法只使用DMSO作为冷冻保护剂并用程控降温仪冷冻技术保存脐血。对二种方法的效果进行比较。结果表明：15份脐血冻存后细胞存活率、CFU—GM回收率，无论在使用非程控降温的第一种方法和使用程控降温仪的第二种方法均无显著性差异。183份脐血质量检测结果及21例临床移植结果也显示两种方法无显著性差异。结论：联合使用DMSO和HES作为冷冻保护剂并用非程控降温冷冻的方法对脐血造血干细胞有良好的保护作用，是一种简单易行、省时省力、适合于脐血造血干细胞库大批量冻存脐血的方法。

Study on Non-programmed Process Using Dimethyl Sulfoxide and Hydroxyethyl Starch as Cryoprotectants in Cryopreservation of Cord Blood Hematopoietic Cells

This study was aimed to search for effective cryoprotectants and freezing methods used in cord blood bank (CBB) for cryopreservation of cord blood hematopoietic stem cells. The non-programmed group using 8% final concentration of dimethyl sulfoxide (DMSO) and 5% final concentration hydroxyethyl starch (HES) (molecular weight 120,000) as protectants and group of conventional of programmed controller method using 10% DMSO only as cryoprotectant in cryopreservation of cord blood hematopoietic stem cells were compared. In each of the two groups, 15 cord blood units were used. In non-programmed group, cord blood units put in -80 degrees C refrigerator for 24 hours as a transitional step before deep-freezing in liquid nitrogen, when both of DMSO and HES had been added. The recoveries of the nuclear cells number, the yield of granulocyto-macrophage colony forming units (CFU-GM) and the cells viability in cord blood units before preservation and after thawing were tested for both methods. The results showed that no significant difference was found in above assays between two groups. The clinical application results also showed that hematopoietic engraftment rates after infusion were similar in both groups. It is concluded that the non-programmed method by -80 degrees C refrigerator as a transitional step and using the combined two protectants seems simple in operation and effective in clinical transplantation as well as the conventional programmed method.