聚羟基丁酸酯-羟基戊酸酯支架复合同种异体软骨细胞修复关节软骨缺损的实验研究

Repairing of articular cartilage defect by allograft chondrocytes embedded in poly hydr-oxybutyrate-co-hydroxyvalerate scaffolds

目的:探讨聚羟基丁酸酯-羟基戊酸酯(PHBV)三维多孔材料作为软骨组织工程支架的可行性及有效性。方法:采用"压片-热处理-粒子析出技术"制备PHBV多孔支架。体外分离培养软骨细胞后接种到PHBV支架体外培养4周,期间扫描电镜观察细胞在支架上的生长情况,然后与单纯PHBV支架同时植入兔膝关节软骨缺损区继续培养4、8、12周后取材,分别行大体、组织学、Ⅱ型胶原免疫组化观察。进行Wakitani评分,观察其体内修复关节缺损效果。结果:电镜观察示软骨细胞在支架上黏附、增殖良好并能分泌细胞外基质,组织学观察示PHBV支架浅层有新生软骨组织形成,于4周后开始形成透明软骨样结构且表面基本平整与宿主整合良好,组织学切片上可见类软骨形成并分泌甲苯胺蓝异染的软骨基质和软骨特异性Ⅱ型胶原。结论:PHBV可以作为软骨组织工程支架材料,能够用于再生修复软骨的缺损。

Objective： To investigate the feasibility and effectivity of using poly （hydr-oxybutyrate-cohydroxyvalerate） （PHBV） as scaffolds for cartilage tissue engineering. Methods： PHBV porous scaffolds were fabricated using compressing molding, thermal processing and salt particulate leaching methods. Chondrocytes isolated from the articular cartilage were seeded into porous PHBV scaffolds. After incubation for 4 weeks in vitro, the chondrocytes cultured for 28 days on the scaffolds were examined by scanning electron microscopy （SEM）. Chondrocytes PHBV constructs were implanted into the joint cave of the rabbit. Control groups were established by articular implantation of PHBV alone. The specimens were excised at 4, 8 and 12 weeks, examined grossly and analyzed by haematoxylin cosine, toluidine blue staining and type Ⅱ collagen immunohistochemistry. Wakitani score was counted to evaluate the repairing effect. Results： SEM showed that chondrocytes could aggregate and synthesize extracellular matrix on the PHBV scaffolds. Both specimens harvested from rabbits and those cultured in vitro exhibited new cartilage formation. After 4 weeks, obvious new cartilage-like tissues were found with smooth surface and well-integrated with the surrounding tissues. Highly positive results were observed on histological and histochemical examinations. Conclusion： PHBV can be used as scaffolds for cartilage tissue engineering. The combinant of chondrocytes and PHBV mixture gel may be an ideal injectable tissue engineering cartilage.