Osteochondral regeneration using autologous cell construct with β TCP

本研究建立了一种单纯细胞构建于TCP上修复骨软骨缺损的新方法，从日本白兔髂嵴中分离获得间充质干细胞（MSCs）。将单层扩增的细胞在TCP上模制成直径4.8mm、高4mm的圆柱体。将标记的自体MSC栓与TCP一起植入兔髌股沟内。膝关节固定一周。分别于术后3、6、12、24、52周处死动物。术后6周，大体观察软骨缺损区表面大部分被软骨样组织覆盖。在一年时再生软骨中保持光滑表面。组织学观察，再生透明软骨中软骨细胞呈柱状分布。在软骨下骨水平，移植物的周边区域发生软骨内骨化，中央区域的小区域保持透明软骨。显微CT显示软骨下骨水平进一步骨化。共聚焦显微镜观察到标记细胞分布于软骨层和软骨下骨层，提示该细胞传递系统可用于骨软骨缺损的治疗，并有可能用于骨关节炎的治疗。

We established a new method to make cell only construct on TCP to repair osteochondral defect.Mesenchymal stem cells (MSCs) were obtained from the iliac crest of Japanese-white-rabbit. Monolayer expanded cells were mold into a cylinder of 4.8mm in diameter and 4mm in height on TCP. The autologous labeled-MSC plug was implanted with TCP in the patellofemoral groove of the rabbit. The knees were immobilized for one week. The rabbits were sacrificed at 3, 6, 12, 24, and 52 weeks after operation. The specimens were evaluated histologically and scanned with micro CT.In gross appearance of the cartilage at 6 weeks, most of the surface of the defect was covered with cartilage-like tissue. Smooth surfaces were maintained in regenerated cartilage at one year. Histologically, columnar distribution of the chondrocyte was observed in regenerated hyaline cartilage. In the subchondral bone level, endochondral ossification occurred at the peripheral area of the transplants, and small area in the central remained hyaline cartilage. Micro CT showed further ossification in subchondral bone level. Confocal microscopy detected the labeled cells both in cartilage layer and subchondral bone layer.The current study suggests that this cell-delivery system can be used for treatment of osteochondral defect and possibly for osteoarthritis.