可同时释放两种骨形态发生蛋白复合支架的制备

目的 研制一种可同时释放骨形态发生蛋白2 (BMP-2)和骨形态发生蛋白7(BMP-7)的生物活性复合支架,以应用于骨组织工程的研究.方法 分别采用复乳溶剂挥发法和相分离法制备负载BMP-2和BMP-7的聚乳酸/羟基乙酸-聚乙二醇(PGLA-PEG)微球和三维多孔的聚己内酯(PCL)支架.然后采用改良的二氯甲烷熏蒸法将PGLA-PEG微球黏附在PCL支架上,形成同时负载BMP-2和BMP-7的复合支架,并检测BMP-2和BMP-7的缓释效果.将人成骨细胞系hFOB1.19分别种植在复合支架和传统支架中,研究支架上的细胞增殖能力和成骨分化能力.结果 制备的复合支架能同时缓慢地释放BMP-2和BMP-7.细胞培养第10天,复合支架上的细胞活性优于传统支架(P＜0.01),细胞形态正常.复合支架上细胞的碱性磷酸酶和Ⅰ型胶原蛋白、骨钙素、骨桥蛋白3种成骨基因的mRNA水平均高于传统支架(P＜0.05,P＜0.01).结论 成功研制出一种可同时释放BMP-2和BMP-7的生物活性复合支架,并可用于骨组织工程的研究.

Bone tissue engineering of a composite scaffold simultaneously releasing two kinds of bone morphogenetic proteins

Objective: 3D polymer scaffold, which can simultaneously released BMP-2 and BMP-7, have been designed in this study, for osteogenic differentiation of OCT-1 cells in bone tissue engineering. Methods: Firstly, the BMP-2 and BMP-7 microspheres of PGLA-PEG were prepared using a emulsion method. And the 3D porous scaffold of PGLA-PEG was also produced by phase separation. To form the composite scaffold loaded with BMPs, the two microspheres were fixed into scaffolds with methylene chloride fumigation technology, for investigation of slow-release effect of BMP-2 and BMP-7. The human osteoblast line cells (OCT-1) were seeded into these composite scaffolds for various tests, including cell proliferation and osteogenic differentiation. Results: The results showed the produced 3D composite scaffolds can successfully loaded with and slow-release the BMP-2 and BMP-7. The OCT-1 cells grew better on 3D composite scaffolds than traditional PCL scaffolds on day 10 of cell culture, and had normal cell morphology. The expressions of ALP collagen type-1(COL-1), osteocalcin (OCN) and osteopontin(OPN) of 3D composite scaffolds was higher than the scaffold without BMPs. Conclusion: The 3D polymer scaffold simultaneously released BMP-2 and BMP-7, have been prepared successfully in this study, for research and application in bone tissue engineering.