全仿生多层复合组织工程支架系统构建研究

The research of building the bionic multilayer composite tissue engineering scaffold system

目的:通过先进的3D打印技术设计并制作一种新型全仿生多层复合支架组织工程支架,完全模拟生理状态下的关节骨-软骨结构,以期为修复骨-软骨全层缺损提供一种新的方法。方法:设计完全模拟生理状态下骨-软骨结构,采用3D生物打印技术和改进的温度梯度热诱导相分离技术(TIPS)设计一种全仿生多层复合支架。通过使用电子显微镜(SEM),免疫荧光染色和显微CT等方法,对新型多层支架结构进行细致观察,评估支架仿生性和微观结构。同时对支架进行生物力学检测,评估其力学性能。结果:电子显微镜(SEM),免疫荧光染色和显微CT观察显示,软骨层支架的表面及内部结构规则,骨支架包含十字交叉结构,拥有较高的孔隙率。钙化层结构致密,可以起到良好的隔离作用,与生理状态下的关节骨-软骨结构完全类似。经生物力学性能测试显示,支架的最大抗拉强度和最大抗剪强度明显高于传统支架。结论:所构建复合多层组织工程支架结构规则,孔隙率高,具有较高的生物力学性能,完全与生理状态下的关节骨-软骨结构一致,可以作为修复关节全层损伤的潜在新方法。

Objective:Use3D printing technology to design and making a new type of tissue engineering scaffolds which have bionic multilayer structures.This kinds of scaffolds can mimic bone and cartilage structures of physiological joints in order to provide a new way to repair bone and cartilage full-thickness defects.Methods:Tissue engineering technology can be used as a potential method to treat full-thickness of joint damage.This study designed a new kind of scaffolds to mimic the structure of bone and cartilage.We used3D printing technology to design and make bone scaffolds and used TIPS technology to design and make cartilage scaffolds.By using electron microscope(SEM),immunofluorescence staining,Micro-CT and other methods,we observed the microstructures of new scaffolds.By using biomechanical tests?we assessed the biomechanical performance of scaffolds.Results:After observing by immunofluorescence staining,SEM,and M icro-CT,w e found that cartilage layer scaffolds had regularly o riented microtubules and bone layer scaffolds had regularly cross frame structures.Both of them had higher porosity.The structures of calcified layer had excellent isolation effects and were completely similar to the normal articular structures.After biomechanical performance test,we found that both of the maximum tensile strength and the maximum shear strength of the new scaffolds were higher than traditional scaffolds.Conclusion:This kind of composite multi-layer tissue engineering scaffolds have higher porosity,regularly cross frame structures and better biomechanical properties.It can mimic the normal articular structures and can be used as a potential method to treat full-thickness of joint damage.