摘要:
BACKGROUND: Particulated juvenile cartilage allograft is simple and easy to obtain, and relevant clinical studies are underway in the USA. However, how the transplanted juvenile cartilage fragments exert biological effects through biochemical mechanisms and genetic signal transduction is still unclear. There is as yet no report on this technology in China. OBJECTIVE: To explore the feasibility of articular cartilage defects repaired with particulated juvenile cartilage allograft. METHODS: The cartilage fragments were obtained from juvenile Pitman-Moore strains (provided by the Laboratory Animal Center of the Army Medical University in China) and cultured in vitro. Brdu immunofluorescence assay was performed at 1, 3, and 7 days of culture. The particulated juvenile cartilage allograft/fibrin gel composites were subcutaneously transplanted into the SCID rats (provided by the Laboratory Animal Center of the Army Medical University). The specimens were taken for hematoxylin-eosin staining, safranin O staining and immunohistochemistry after 1 month. Cartilage defects of 8 mm in diameter were made in the knee joint of 10 adult Pitman-Moore strains (Laboratory Animal Center of the Army Medical University), and were randomized into two groups, which were then transplanted with the particulated juvenile cartilage allograft/fibrin gel composites (experimental group) or nothing (control group). The specimens were taken for hematoxylin-eosin staining, safranin O fast green staining, toluidine blue and immunohistochemistry at 3 months after transplantation. RESULTS AND CONCLUSION: Little Brdu incorporation was detected in juvenile cartilage fragments at 1 day of culture, some Brdu incorporation was defected at 3 days of culture. At 7 days of culture, a progressive increase in the Brdu signal was detected in chondrocytes within the cultured cartilage fragments, which seemed to localize along the tissue edge. At 1 month after subcutaneous transplantation, the particulated juvenile cartilage allograft still survived and were surrounded by few proliferative chondrocytes. There was no obvious tissue repair in the control group at 3 months after transplantation. In the experimental group, there was obvious tissue repair, the color of the newly formed tissues was similar to the normal cartilage tissue, which integrated well with the surrounding normal cartilage tissue, and the cells distributed evenly. These results imply that particulated juvenile cartilage allograft can achieve good results in repairing articular cartilage defects.%背景:同种异体幼年软骨微粒制备简单, 获取容易, 该技术在美国已经进入临床研究阶段, 但临床上还处于"黑箱"操作阶段, 对于移植的幼年软骨微粒是如何通过生物化学机制和基因信号转导发挥生物学效应, 目前还不清楚.目前, 中国还没有相关技术的报道.目的:探索同种异体幼年软骨微粒移植修复关节软骨缺损的可行性.方法:从幼年贵州小香猪 (陆军军医大学实验动物中心提供) 膝关节获取同种异体幼年软骨微粒, 体外培养1, 3, 7 d进行Brdu免疫荧光检测.将同种异体幼年软骨微粒/纤维蛋白凝胶复合物移植于SCID大鼠 (陆军军医大学实验动物中心提供) 皮下, 1个月后取材, 进行苏木精-伊红染色、番红染色、免疫组织化学检测.在10只成年贵州小香猪 (陆军军医大学实验动物中心提供) 膝关节髌骨面制作直径8 mm的软骨缺损, 随机分2组干预, 实验组软骨缺损处移植同种异体幼年软骨微粒/纤维蛋白凝胶复合物, 空白组不移植任何材料, 3个月后取材, 对修复组织进行苏木精-伊红、番红-固绿、甲苯胺蓝、免疫组织化学检测.结果与结论: (1) 在同种异体幼年软骨微粒的体外培养中, 第1天见到极少的软骨细胞脱落与增殖;第3天可见少量的软骨细胞脱落与增殖;第7天见到有明显的细胞脱落与增殖, 且增殖的细胞分布在切缘周围; (2) 皮下移植1个月后, 移植的同种异体幼年软骨微粒仍然存活且周围有少量的软骨细胞增殖; (3) 软骨缺损修复3个月后, 空白组未见明显修复组织;实验组可见明显的修复组织, 新生的软骨组织颜色与正常软骨组织颜色相似, 且与周围正常软骨组织界面整合良好, 细胞分布较均匀; (4) 结果表明, 同种异体幼年软骨微粒修复关节软骨缺损可取得良好的效果.