聚乙二醇载药缓释微球复合去细胞瓣制备组织工程心脏瓣膜支架

The research of decelluarized valve scaffolds modified by polyethylene glycol microspheres loading transforming growth factor-β1

目的:制备聚乙二醇(PEG)载药缓释微球复合去细胞瓣组织工程心脏瓣膜(TEHV)支架。方法:制备PEG微球,电镜观察粒径。去细胞瓣与PEG微球偶联,吸附转化生长因子(TGF-β1)。行ELISA检测,分子生物学、形态学和生物力学检测。结果:PEG微球粒径(42.72+3.48)nm。酶联免疫吸附检测示缓释效果明显,7dTGF-β1释放率67.22%,PEG微球的TGF-β1包封率为82.01%。与单纯去细胞瓣膜比较,复合支架羟脯氨酸含量和DNA含量无显著变化,形态学检测显示复合支架细胞外基质联合紧密,胶原纤维结构紧凑,且瓣叶生物力学性能提高。结论:制备PEGTGF-β1缓释微球去细胞瓣复合支架可行。

Objective：To prepare decelluarized valve scaffolds modified by polyethylene glycol microspheres loading transforming growth factor-β1.Methods：PEG microspheres were produced by an emulsion-crosslinking method,scanning electron microscopic observation was performed to examine the average diameter. Decelluarized valve scaffolds,prepared by trypsinase and TritonX-100,were modified with PEG microspheres by EDC a coupling reagent,then TGF-β1 was loaded into them by adsorption. Controlled release of TGF-β1 was measured by enzyme-linked immunosorbent assay（ELISA）,HE staining and scanning electronic microscopy were performed,and cell DNA assay,hydroxyproline content ,biological mechanic properties of leaflets were measured. Results：PEG microspheres were obtained in the average diameter of（42.72＋3.48）nm.During monitoring of the controlled release,a stable release process could be observed. The percentage of cumulative release was 67.22% within 7 days and the encapsulation efficiency was 82.01%. Compared with the simple decelluarized valve scaffolds,the modified scaffolds have compact structures in extracellular matrix and advantages in biological mechanics. And there were no significant changes in DNA assay and hydroxyproline content in the modified scaffolds.Conclusion：Decelluarized valve scaffolds modified by PEG microspheres loading TGF-β1 are prepared successfully.