兔膝关节软骨及软骨下骨改变生存环境后的转归

目的应用关节镜灌洗术、软骨下钻孔术、骨膜或软骨膜移植等方法治疗关节软骨损伤,透明软骨得不到真正的修复。因此以自体或异体软骨细胞、骨髓基质细胞为种子细胞修复关节软骨并观察关节透明软骨细胞和骨髓基质细胞在体内不同微环境中的变化。方法新西兰兔9只,在股骨髁髌骨滑车关节面钻取两个直径2.5mm、深3mm的骨软骨块,将软骨面向下、软骨下骨向上原位倒置,分别于4,8,12周取材,做大体观察和苏木精-伊红(HE)染色、safranin-O染色、II型胶原免疫组化。结果4周时倒置体表面有纤维组织覆盖,原关节软骨细胞形态结构正常。8～12周,倒置体表面有纤维软骨再生,原关节透明软骨基本保持其原有特性。结论以骨松质为支架的骨髓基质细胞未能完全修复关节软骨损伤。修复关节软骨最好采用同一组织来源的透明软骨细胞。

The fate of articular cartilage and subchondral bone after the variety of microenvironment in rabbits

Aim investigate the change of hyaline cartilage cells and marrow stromal cells in the different local microenvironment respectively. Methods Two osteochondral grafts,2.5 mm in diameter and 3.0 mm in deep were obtained from the femural trochlea articular surface of 9 New Zealand white rabbits.The grafts were deep enough into the subchondral cancellous bone,or into the bone marrow plainly,and the autografts were then implanted upside down in site,namely,the articular cartilage faced marrow and managed to keep the surface which had approached bone marrow smooth.The animals were killed at 4,8,12 weeks postoperative respectively.Evaluation included gross appearance of the healed grafts,histological investigation using haematoxylin and erosin and Safranin O staining and with immunohistochemical staining for type II collagen.Results At 4 weeks postoperatively,the surface of inversion was covered with thin fibrous tissue, with the margins clearly defined.At 8 and 12 weeks after operation,a relative smooth articular surface was restored,and the margins of the autografts were not clearly distinguishable.By this time,fibrocartilage was observed at the reparative surfacing of upside down grafts while the original articular cartilage still almost kept their inherent phenotype.Conclusion MSCs with cancellous bone being scaffold fails to repair articular cartilage.Undifferentiated bone marrow derived osteochondral progenitor cells offer a possible alternative to repair cartilage defect if their capacity is enhanced to differentiate into cartilage with the technology of cytokines induction or gene modification.