一种新型生物反应器在造血干/祖细胞体外扩增中的应用

The Application of a New-type Bioreactor in the ex vivo Expansion of Hematopoietic Stem/Progenitor Cells

摘要:

针对造血干/祖细胞体外扩增对培养环境的需求, 结合静/动态培养的特点, 开发了一种新型的生物反应器用于造血干/祖细胞的体外扩增。在该生物反应器内, 采用SCF+TPO+Flt-3细胞因子组合, 比较了静态和循环培养两种方式体外扩增脐血CD34+细胞的效果。培养7 d后, 总细胞分别扩增了(13.86 ± 4.26)和(7.23 ± 2.67)倍, 显示静态培养有利于总细胞的扩增; CD34+细胞扩增倍数、培养物中CD34+细胞含量均相近, 无显著性差异; 而CD34+CD38-细胞扩增倍数以及培养物中CD34+CD38?细胞的百分含量分别为(1.82 ± 0.58)和(3.90 ± 0.85)倍以及(9.45 ± 4.85)和(37.47 ± 14.06)%, 循环培养明显高于静态培养。可见, 在该生物反应器内, 采用静态和循环两种培养方式, 均能实现造血干/祖细胞的体外扩增, 但静态培养促使造血干细胞向定向祖细胞分化, 而循环培养则更有利于早期造血干细胞的扩增。

关键词:造血干/祖细胞, CD34+细胞, 体外扩增, 生物反应器

Abstract:

Based on the requirement of culture conditions for hematopoietic stem and progenitor cells (HSPCs) ex vivo expansion, we developed a new-type bioreactor by combining superiorities of static and stirred culture models. Stem cell factor(SCF), thrombopoietin(TPO), FLT-3 ligand(Flt-3) were used as the cytokines cocktails. The effects of the static and cyclic culture on the expansion characteristics of CD34+ selected cells were compared in the new-type bioreactor. After 7 d cultures, the expansion of total cells in the static culture was 13.86 ± 4.26 fold, higher than that in the cyclic culture (7.23 ± 2.67 fold). The analysis of the fold expansion and the proportion of CD34+ cells showed that there was no marked difference between the static culture and the cyclic culture. However, the fold expansion and the proportion of CD34+CD38- cells were higher in the cyclic culture than those in the static culture (3.90 ± 0.85 versus 1.82 ± 0.58), which reflected more primary CD34+CD38- cells were obtained in the cyclic culture. The above results demonstrated that both the static culture and the cyclic culture could be used in ex vivo expansion of CD34+ cells with the new-type bioreactor. In static culture hematopoietic stem cells differentiated into progenitor cells, whilst the cyclic culture favored the expansion of primary HSPCs.

Key words:hematopoietic stem and progenitor cells (HSPCs), CD34+ cell, Ex vivo expansion, bioreactor