Osteochondral regeneration using autologous cell construct with β TCP

我们建立了一种仅在TCP上构建细胞修复骨软骨缺损的新方法。从日本白兔髂骨获得间充质干细胞（MSCs）。将单层膨胀细胞在TCP上模制成直径4.8mm，高4mm的圆柱体。将自体标记间充质干细胞塞与TCP植入兔髌骨股沟。膝盖固定了一个星期。分别于术后3、6、12、24、52周处死。对标本进行组织学检查和显微CT扫描。在6周软骨的大体外观中，缺损的大部分表面被软骨样组织覆盖。一年后再生软骨表面保持光滑。组织学上，再生的透明软骨软骨细胞呈柱状分布。在软骨下骨水平，移植体外周区出现软骨内骨化，中央小区域保留透明软骨。显微CT显示软骨下骨进一步骨化。共聚焦显微镜在软骨层和软骨下骨层均检测到标记细胞。目前的研究表明，这种细胞递送系统可用于治疗骨软骨缺损，并可能用于骨关节炎。

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.