纳米电纺膜对软骨再生的免疫保护作用及其机制

Engineered articular cartilage has achieved primary success in clinical translation. However, no breakthrough has been achieved so far for engineered cartilage in subcutaneous enviroment of an immunocompetent animal model, and immunological factor is possible the key factor which influencing cartilage regeneration. According to our previous studies, the electrospun gelatin/polycaprolactone（GT/PCL） nanofibers membranes as scaffold could be successful used for cartilage regeneration in subcutaneous enviroment of an immunocompetent animal model. However, the quality of engineered cartilage was conflit with the reasult in immunnocompromised animal models. We hypothesis that the elactrospun nanofibers membranes have immuno-protection effect. This is only a hypothesis, but also the need for more research to prove, for example: does the scaffold have immuno-protection effect? How does the mechanism of the scaffold influence the immunological process?In this project,these questiona will be systematically investigated. Fistally, the scaffolds with different pore size will be prepared by Electrospinning method and 3D-printing method. The samples which the scaffold with different pore size as package and the same cell-scaffold as inner core, will be cultivated in subcutaneous enviroment of an immunocompetent animal model. The connection of pore size and the quality of cartilage will be evaluted. Secondly, the mechanism of inflammatory infiltration will be systematically investigated by evaluting the category and the quantity of inflammatory cells and inflammatory mediator. At last, we will explore the application prospects of the immuno-protection scaffolds in Allogenic animinal model. By these investigations, the problem of cartilage regeneration difficulty in subcutaneous enviroment of an immunocompetent animal model is expected be solved, which apparently helps to promote the clinical translation of engineered cartilage.

组织工程关节软骨已初步实现临床转化，但皮下环境的软骨再生一直未获突破，免疫因素可能是造成这种差异的关键。申请人前期研究发现，明胶/聚已内酯（GT/PCL）纳米电纺膜复合软骨细胞可以在大动物皮下成功构建软骨，但软骨再生规律与裸鼠完全相反。据此申请人提出假说：纳米电纺膜对软骨再生具有免疫保护作用。但该假说是否成立，其免疫保护作用机制及应用前景如何目前仍不清楚。针对这些问题，本项目拟从以下三方面展开研究：1）通过电纺、3D打印等方法设计不同孔径材料，包裹相同细胞材料复合物，在大动物皮下验证外部材料孔径与内部软骨再生质量的关联；2）在细胞和分子水平定性定量检测炎症细胞和炎症介质的浸润情况及其与软骨再生质量的关联，阐明其免疫保护机制；3）探讨该免疫保护材料改善大动物同种异体软骨再生的可行性。本项目的顺利完成有望为解决大动物及人皮下环境中软骨再生的难题提供理论基础及关键技术参数。

组织工程关节软骨已初步实现临床转化，但皮下环境的软骨再生一直未获突破，免疫因素可能是造成这种差异的关键。申请人前期研究发现，明胶/聚已内酯（GT/PCL）纳米电纺膜复合软骨细胞可以在大动物皮下成功构建软骨，但软骨再生规律与裸鼠完全相反。据此申请人提出假说：纳米电纺膜对软骨再生具有免疫保护作用。但该假说是否成立，其免疫保护作用机制及应用前景如何目前仍不清楚。为证实这一假说，按照项目最初设计的研究思路，本课题从体外细胞实验，自体和异体大动物实验几个方面入手，建立了研究免疫隔离作用的细胞材料模型，证实纳米电纺膜在体外具有隔离细胞的作用，证实了纳米电纺膜具有促进自体和异体大动物皮下软骨再生的作用，并且证实这种免疫保护作用和材料的孔径具有相关性,相关的分子机制还在进一步的研究中。此外，还证实细胞膜片技术可以成功构建具有精确形态的耳廓状软骨，体外静水压反应器可以明显提高构建软骨的质量，本项目相关研究成果已发表SCI收录论文2篇，总SCI影响因子约8分，中文科技核心期刊论文2篇，培养研究生4名，全面完成了各项研究任务与考核指标。这些研究成果对于皮下环境软骨再生的临床应用转化奠定了坚实的基础。