中文摘要：

骨髓间充质干细胞（MSCs）具有多向分化的潜能，是重要的组织工程“种子细胞”和理想的基因治疗靶细胞，但在骨髓中的含量非常少，需体外扩增才能满足临床需求。今将第四代MSCs与Ⅰ型胶原溶液混合后接种于中空纤维膜（HFMs）内，置37℃、5％CO2、饱和湿度的培养箱内1h后形成凝胶，然后将此HFMs接种至气升式环流生物反应器（ALB）内，进行MSCs的三维动态培养与扩增。实验过程中每24h取样测吸光度、计细胞数、绘制细胞生长曲线，测定细胞代谢参数，并对扩增的细胞进行流式细胞仪分析及多向诱导分化检测。结果表明；在气升式环流中空纤维膜生物反应器（ALHFMB）内，O2含量基本保持恒定；细胞代谢旺盛，MSCs扩增倍数明显增加，7d后扩增近16倍；扩增的细胞仍保持MSCs表型并具有较强的成骨、成软骨及成脂肪的多向分化能力。

英文摘要：

Mesenchymal stem cells （MSCs）, having the potential of multi-differentiation, are the promising ＂seed cells＂ in tissue engineering and ideal target cells in gene therapy. However, MSCs are in small quantity in bone marrow and are needed to be expanded in vitro to meet clinical need. In this paper, MSCs of passage 4 （P4） mixed with type I collagen were inoculated into hollow fiber membranes （HFMs）, which formed gel under the conditions of 37℃, 5% CO2 and saturated humidity for 1 h and then were inoculated into an air-lift loop bioreactor （ALB） to culture and expand MSCs in three dimensions. During the experiments, the OD value of medium culturing MSCs in HFMs was detected every 24 h to calculate the cell number and to obtain the cell growth curves, and the metabolic parameters were also detected. Moreover, the expanded cells were identified with flow cytometer and through inducing them to multi-differentiate. The results show that the air-lift loop hollow fiber membrane bioreactor （ALHFMB） can keep O2 concentration almost constant. MSCs metabolize robustly and expand nearly 16 fold in the bioreactor after 7 d. And the expanded cells still maintain MSCs phenotypes and have the multi-differentiation potential of becoming bone, cartilage and adipose.