基于RGD修饰的TiO2纳米点调控细胞薄层培养技术促进组织工程骨中三维血管生成及机制研究

应用组织工程技术构建的生物骨组织植入宿主后其内毛细血管生长缓慢，不利于骨组织的生长、改建及支架材料降解，故生物骨组织的早期血管化对于骨组织的修复及重建具有重要的意义。为了促进组织工程骨的早期血管化，本研究开创性采用基于RGD修饰的二氧化钛纳米点调控光控细胞薄层培养技术，分别获取来源于小鼠的成骨前体细胞、血管内皮细胞及成骨前体细胞/血管内皮细胞共培养并附带有细胞外基质及RGD的细胞片层，通过层层组装多型复合细胞片层及定向诱导的立体培养方法，构建具有三维毛细血管网状结构的组织工程骨并探讨其形成机制。将此组织工程骨植入实验动物骨缺损，观察宿主与组织工程骨之间血管吻合和骨结合的状况，以证实其再血管化及骨缺损修复的效率。本研究为体外培养含有三维毛细血管网状结构的组织工程骨奠定了基础，从而为进一步优化体外复合组织的培养提供了实验依据。

The application of tissue engineering technology in constructing biological bone tissue has the defective of growing slow of capillary vessel. This is hard for tissue growing, rebuilding and scaffold materials degradation. So the pre-vascularization of biological bone tissue is significant for repairing and rebuilding of bone tissue.In order to promoting the primitive vascularization of tissue engineered bone, our study initiatively used light-responsived cell sheet engineering which is controled by TiO2 nanodot modified with RGD to obtain cell sheet about mice MC3T3-E1, endothelial cell and the coculture of the two which involved ECM and RGD. Then the cell sheet was assembled as multicoat cell sheet and cultured in three dimension with directional induction so that to construct tissue engineered bone with three dimension reticular formation of capillary vessel. We also investigate the forming mechanism. Grafting the tissue engineered bone into the defect, we observe the inosculating of vessel and bone bonding between parasitifer and tissue engineered bone to confirm the efficiency of revasculatization and bone repairing. The study investigated these to settle the foundation of culturing tissue engineered bone with capillary vessel. Furthermore, it will give the evidence to optimize culturing complexed tissue in vitro.