SF/CS/nHA仿生支架结合骨软骨镶嵌移植术和PRP对大面积骨软骨缺损修复的研究

At present, The repair of osteochondral defects in tissue engineering has been made a significant progress. However, it has still not a osteochondral scaffold system matching as the "gold standard", especially for large area of cartilage defects. In our previous study, we have achieved good results from the study of the single aperture scaffold of SF/CS and SF/CS/nHA, and have published 2 SCI papers with these results.Nevertheless, the single aperture scaffold still unable to meet the progressive structure of bone and cartilage from shallow to deep, especially for large area of cartilage defects.The research on the basis of we have successfully prepared the osteochondral scaffold of gradient aperture SF/CS/nHA,which assisted osteochondral mosaicplasty method, intends to implant in large area osteochondral defects, the mixture with the adipose derived mesenchymal stem cells (ADSCs) carrying bone morphogenetic protein 2 (BMP-2) and injectable platelet rich plasma (PRP) gel was injected into the space between the brackets and the surrounding tissue, and further solving the problem of integration of osteochondral residual, in order to realize the reconstruction of large osteochondral defect. At the same time, the mechanism of scaffold degradation, release of growth factor and the formation of scaffold in osteochondral in vivo. These results will provide an experimental basis of a better match of the osteochondral reconstruction and a closer to the metabolic and physiological characteristics.

当前，利用组织工程修复骨软骨缺损已取得重大进展，但至今没有一种与骨软骨更为匹配的作为“金标准”的支架系统，尤其是对于大面积的软骨缺损。本课题组在前期研究单一孔径的SF/CS和SF/CS/nHA支架中取得较好的实验结果（研究论文SCI收录2篇）。然而单一孔径支架依旧无法满足骨与软骨的渐进式结构, 尤其是对大面积的软骨缺损。故本课题组在成功制备梯度孔径的骨软骨SF/CS/nHA支架的基础上，拟结合骨软骨镶嵌移植术将支架植入大面积骨软骨缺损，再将携带目的基因骨形态发生蛋白2（BMP-2）的脂肪间充质干细胞（ADSCs）与可注射型富血小板血浆(PRP)凝胶混合后注入支架和支架周围间隙，进一步解决残留的骨软骨柱间隙的整合问题，以期实现重建大面积骨软骨缺损的修复，同时探明支架材料的降解、生长因子控释以及支架在体内骨软骨的形成机制，为制备与骨软骨重建更匹配、更接近生理代谢特征的种植体提供实验依据。

当前，利用组织工程修复骨软骨缺损已取得重大进展，但至今没有一种与骨软骨更为匹配的作为“金标准”的支架系统，尤其是对于大面积的软骨缺损。本课题组在前期研究单一孔径的SF/CS和SF/CS/nHA支架中取得较好的实验结果（研究论文SCI收录2篇）。然而单一孔径支架依旧无法满足骨与软骨的渐进式结构, 尤其是对大面积的软骨缺损。本课题组利用离心、冷冻干燥及化学交联相结合的方法，成功制备了SF/CS/nHA梯度孔径骨软骨支架并完成了相关指标检测，符合实验需要。本研究成功培养了山羊骨髓间充质干细胞，并利用基因重组技术导入EGFP、BMP-2构建目的基因质粒，成功制备了可注射型富血小板血浆(PRP)凝胶，将两者混合后注入支架和支架周围间隙，在电镜下观察ADSCs-支架复合体中细胞形态及分布得出：各层支架孔隙内壁上可见大量细胞粘附，细胞形态大小均一，呈长梭形紧密排列，未出现明显的细胞破碎或形态异常，说明支架生物相容性良好，无细胞毒性，不会导致细胞发生畸形、变异、破裂等毒性现象。这一实验结果进一步解决了残留的骨软骨柱间隙的整合问题，以期实现重建大面积骨软骨缺损的修复，同时探明支架材料的降解、生长因子控释以及支架在体内骨软骨的形成机制，为制备与骨软骨重建更匹配、更接近生理代谢特征的种植体提供实验依据。