体外扩增脐血CD_(34)^+细胞的实验研究

Experimental study on ex vivo expansion of CD_(34)^+ umbilical cord blood cells

目的 探讨体外扩增脐血干 /祖细胞用于成人脐血移植的可能性。方法 从 10份新鲜的脐血标本中纯化的CD3 4+ 细胞接种于含体积分数为 2 0 %的胎牛血清 (FBS)的IMDM培养基的悬浮培养体系中 ,分别加入由SCF、Flt 3Ligand (FL)与IL 1β、IL 3、IL 6、G CSF、Epo(合称 136GE)组成的 3组细胞因子 (A组 :136GE +FL ;B组 :SCF +136GE ;C组 :FL +SCF +136GE)培养扩增 7d。结果 ①A组与B组对各阶段造血细胞扩增效果差异均无显著性 ,但B组各项结果在一定程度均优于A组 ,C组各项结果均显著优于A组 (P <0 .0 1)和B组 (P <0 .0 5 ) ,FL与SCF有明显的协同效应 ;② 30 %的脐血标本在FL +SCF +136GE的刺激下经过 7d扩增后可以获得 >5 0× 10 6的CD3 4+ 细胞 ,这可能足够用于 5 0kg以上的成人做干细胞移植 ;③从扩增产物中再纯化的CD3 4+ 细胞保留原CD3 4+ 细胞的集落形成率、CD3 4+CD3 8-亚群的比例以及体外扩增潜能。结论 体外扩增脐血CD3 4+ 细胞有可能产生足够供成人移植所需的造血干 /祖细胞。

Objective To investigate the potential possibility that to expanse ex vivo umbilical cord blood (UCB) cells to an amount sufficient adults transplantation. Method Purified CD 34 + UCB cells from 10 fresh UCB samples were cultured for 7 days in IMDM mediums containing 20% FBS and one of the following three combinations: Group A(IL 1β+IL 3+IL 6+G CSF+Epo+FL),Group B(SCF+IL 1β+IL 3+IL 6+G CSF+Epo) and Group C(FL+SCF+IL 1β+IL 3+IL 6+G CSF+Epo). Result ①There was no significant difference between Groups A and B in expansion of UCB cells. But in group C,the expansion was greater than that in group A (P<0.01) or group B(P<0.05). The effects of FL and SCF were synergistic. ②Over 50×10 6 CD 34 + cells which are sufficient for adult transplantation were obtained in 30% of UCB samples in group C. ③ The expanded CD 34 + UCB cells retained original clonogenic efficiency, the primitive CD 34 +CD 38 - proportion and the expansion potential were the same as fresh UCB cells. Conclusion The ex vivo expansion of CD 34 + UCB cells might provide sufficient hematopoietic stem cells for adult transplantation.