冻存时间对脐血造血细胞体外增殖潜能的影响

EFFECTS OF CRYOPRESERVATION LENGTH ON THE PROLIFERATIVE POTENTIAL OF CORD BLOOD HEMATOPOIETIC CELLS IN VITRO

目的 :研究冻存时间对脐血造血细胞增殖潜能的影响。方法 :在所分离的脐血有核细胞中加入联合低温保护剂Dextran 4 0 +10 %DMSO ,经梯度降温后置液氮深低温保存。采用无血清造血细胞扩增液对冻存不同时间的脐血造血细胞进行体外扩增 ,动态监测扩增潜能。结果 :将冻存 1个月、4个月脐血造血细胞体外扩增 5周 ,其总有核细胞分别被扩增了 (14 99.0± 115 .6 )倍和 (15 13.0± 110 .4 )倍 ,CFCs均于体外扩增的第 3周达到高峰 ,分别扩增了(5 3.8± 6 .3)倍和 (5 4 .8± 6 .7)倍 ,CD34+ 造血细胞于体外扩增的第 2周均达到高峰 ,分别扩增了 (6 3.8± 6 .1)倍和(6 2 .4± 5 .7)倍 ;统计分析冻存 1个月与 4个月后造血细胞扩增结果 ,不存在显著性差异 ,P >0 .0 5。结论 :在适宜深低温条件下冻存脐血造血细胞 ,在一定时间内 ,冻存时间的长短不会导致其增殖潜能下降。

Aim: To study the effects of cryopreservation length on the proliferative potential of hematopoietic cells derived from cord blood. Methods: Using Dextran 40 and 10%DMSO as cryoproductants, separated nuclear cells were stored in liquid nitrogen after they were freezed according programme. One month or 4 months later, they were thawed and expanded in serum free medium for culture and expansion of hematopoietic cell(SFEM) for 5 weeks. Dynamic results were detected every week. Results: At the 5th week of expanding, TNC were expanded for 1499.0±115.6 folds and 1513.0±110.4 folds, respectively. CD34 + cells and CFCs reached to their highest level at the 2nd week and at the 3rd week. CD34 + cells were expanded for 63.8±6.1 folds and 62.4±5.7 folds, respectively. CFCs were expanded for 53.8±6.3 folds and 54.8±6.7 folds, respectively. Between the two kinds of cells, statistical significant difference in proliferative potential wasn`t detected. Conclusion: In ideal cryopreservative condition, the cryopreservation length would do not affect the proliferative potential of cord blood hematopoietic cells.