Research the origin of cells that contribute to the repair of osteochondral defect and application this for the acceleration of the tissue repair.

本研究采用绿色荧光蛋白转基因（GFP）大鼠模型，探讨了外周血循环细胞参与关节骨和软骨损伤的自然修复过程的可能性。本研究采用绿色荧光蛋白大鼠与野生型大鼠的共生模型。联体术后2周，流式细胞术分析证实了血管交通。1.5在股骨髌骨沟内造成直径1.0mm、深1.0mm的骨软骨缺损。分别于术后1、2、4、24周行组织学检查。术后早期，两种联体大鼠缺损处均可见GFP阴性和阳性细胞。联体野生鼠修复组织中部分可见GFP阳性软骨细胞。在手术后的晚期阶段，修复的缺损被来自邻近组织的细胞而不是来自外周血的细胞占据。术后1周，修复组织中来自外周血的细胞约占30-40%。而在术后24周，这一比例约为0- 7%。结果表明，外周血中循环的细胞不仅提供了修复所需的因子，而且还提供了修复细胞，对关节骨软骨缺损的修复起着重要作用，尤其是在早期，当给大鼠注射粒细胞集落刺激因子（G-CSF，150μg/kg，每日1次，连续5天）时，血中有核细胞增多。细胞增殖后，制作直径1.5mm、深1.0mm的骨软骨缺损，观察24周。软骨修复不明显，但软骨下骨修复明显加快。为了获得更好的修复，我们通过注射G-CSF 14天来增加有核细胞。待细胞增殖较多后，制作缺损，观察2周。当我们比较前一种方法和新方法的修复时，它们之间没有显著差异。

We examined the possibility that cells circulating in peripheral blood participated in a natural repair process of the joint bone and cartilage injury by using green fluorescent protein transgenic transgenic(GFP) rat. In this study, we used the parabiosis model of GFP rat and wild one. Two weeks after parabiosis operation, vascular communication was confirmed by flow cytometry analysis. 1.5 mm diameter and 1.0 mm depth osteochondral defect was made in patella groove of femoral bone. Histrogical examination was done at 1, 2, 4, 24 weeks after surgery. In the early phase after the surgery, there were both GFP negative and positive cells in the defects of both rats of parabiosis. GFP positive chondrocytes was confirmed partly in the repair tissue of the wild rat of parabiosis. In the late phase after the surgery, the repaired defect was occupied by cells originated from the adjacent tissue not from the peripheral blood. The rate of cells originated from the peripheral blood was about 30-40% in the repair tissue at 1 week after surgery. While at 24 weeks after surgery that was about 0-7%. From these results, it is confirmed that cells circulating in peripheral blood contributed to repair of osteochondral defects in joint especially in early phase not only supplying the factors needed for repair but also supplying the repair cells.When injected granulocyte colony stimulating factor(G-CSF ; 150μg/kg pre day for 5 days) to rats, the nucleated cells in blood increased. After the cells increase, we made 1.5mm diameter and 1.0 mm depth osteochondral defect and observed up to 24 weeks. The repair of subchondral bone was accelerated although that of cartilage did not. To obtain better repair, we increased the nucleated cell more by injecting G-CSF for 14 days. After the cells increased more, we made defects and observed for 2 weeks. When we compared the repair of the preceding method with the new one, there were no significant differences between them.