rhBMP-2／PLGA缓释支架的制备及对MSCs细胞成骨活性的体外研究

Preparation of PLGA scaffold with controlled release of rhBMP-2 and its effect on the osteogenic activity of MSCs in vitro

目的探讨骨形态发生蛋白（rhBMP-2）的聚乳酸聚乙醇酸共聚物（PLGA）体外缓释生物支架对人骨髓间充质干细胞（MSCs）细胞的影响。方法采用粒子沥滤-冷冻干燥复合工艺制备了附载rhBMP-2的PLGA生物支架，并检测了在PLGA的降解过程中rhBMP-2的释药规律；同时分离培养人骨髓间充质干细胞，体外培养后分别接种于附载和未附载rhBMP-2的PLGA支架上。扫描电镜观察不同时间段MSC在支架上的生长情况；MTT法测定细胞增殖情况。结果rhBMP-2能被包裹进PLGA支架中，而且可以在PLGA支架降解过程中持续释放出来并诱导骨发生。结论骨形态发生蛋白的PLGA复合载体是一种较为理想的新型生物支架。

Objective To assess the feasibility of using biodegradable poly（lactic-co-glycolic acid） （PLGA） scaffold with controlled release of rhBMP-2 and its effect on the osteogenic activity of MSCs in vitro. Methods The PLGA scaffolds with rhBMP-2 sustained release system were made by combination of porogen- leaching and freeze-drying. The drug release kinetics was measured by enzyme-linked immunosorbent assay （ELISA） in vitro. MSCs were isolated from the bone marrow of human and cultured for 3 passages. Then, MSCs were seeded onto PLGA scaffolds. PLGA scaffolds without rhBMP-2 were used as experimental controls . Scanning electron microscopy（SEM） was used to observe the morphology of MSCs. The cell proliferation was determined by MTT assay. Results The rhBMP-2 was encapsulated into PLGA scaffolds and it was found to be continuously released from the scaffolds. The scaffolds have evident enhancing effect on ectopia osteogenesis. Conclusion PLGA scaffold containing rhBMP-2 is a new promising tissue engineering scaffold.