利用hBMSCs在生物反应器中构建小口径血管的实验研究

Investigation on small-sized blood vessel construction in bioreactor by using hBMSCs

目的采用改进的生物反应器系统,应用人骨髓间充质干细胞(hBMSCs)构建小口径的组织工程血管。方法设计一套血管生物反应器系统,采用有限元方法对组织工程小血管托架材料进行分析,从而设计一套用于构建直径为2mm的小血管托架;收集人的原代骨髓基质干细胞进行体外扩增和培养,选用第3代细胞与聚羟基乙酸酯(PGA)复合后置于血管生物反应器中动态培养;培养4周后,对材料复合物取材,进行大体观察、HE染色、扫描电镜和平滑肌免疫组化等指标检测。结果血管色泽明亮,有一定的弹性,用镊子反复压下血管能够反弹恢复原样;细胞分泌的胶原基质排列较规则,免疫组化结果表明血管含有平滑肌弹性肌动蛋白的成分。结论改进的血管生物反应器能模拟血管的力学环境,并能利用hBMSCs成功构建组织工程化小血管组织。

Objective To construct small-sized tissue-engineered blood vessels with hBMSCs（human Bone Marrow Stromal Stem Cells） in our improved bioreactor system. Methods A set of bioreactor system was designed with the application of Finite Element Methods as an analysis method to construct tissue engineered blood vessels with the diameter of 2mm, hBMSCs werefirst collected and further cultivated, The third passage of the cultivated cells were then seeded on the polyglycolic acid （PGA） to fabricate the cell-scaffold compound. This compound was subsequently subjected to dynamical culturing in the blood vessel bioreactor. Results Tissue-engineered blood vessels can be constructed by culturing the hBMSCs-PGA compound under a dynamic condition. After 4 weeks, the tissues were removed from the bioreactor and subjected to analysis by visual observation, HE, SEM（scanning electron microscope） and immunohistochemistry for smooth muscle α-Actin, It was observed that the tissue-engineered blood vessel appeared bright color and has certain elasticity. The secreted collagen matrix arrayed orderly around the cells and smooth muscle elastic actin can also be detected in the formed tissues. Conclusion The in vivo biological conditions of blood vessels can be simulated using the current blood vessel bioreactor system, Using hBMSCs, the construction of the tissue engineered small-sized blood vessels can be successfully achieved in our bioreactor system.