软骨损伤后基质细胞衍生因子1的表达

目的：研究骨髓间充质干细胞趋化聚集软骨损伤病灶的可能机制,为调控和干预软骨损伤时干细胞定向迁移和聚集提供理论和实验依据。方法：制作兔软骨损伤模型,分别于制模后2、5、7、10、14、28天处死兔子,取损伤灶及边缘区组织,利用组织裂解液提取总蛋白,分别行酶联免疫法夹心法检测SDF-1表达和体外细胞迁移实验,部分兔软骨损伤制模成功后,行细胞体内移植,观察SDF-1对MSCs、软骨细胞的迁移影响。结果：SDF-1的表达呈现出时间变化的趋势,制模后7天达到高峰水平。制模后的软骨组织对MSC迁移的影响与SDF-1的表达呈相同的变化程序,制模后7天对MSC的趋化作用最强。SDF-1 存在时,MSCs 迁移活跃,应用抗体封闭CXCR4 后,这种迁移显著减弱。体内移植的MSCs主要聚集在损伤灶周围,但在封闭CXCR4 后,这种聚集现象大大减弱。结论：软骨损伤的早期,损伤灶内修复组织中SDF-1的表达明显升高,并可在损伤后2周内维持在一个相对高的水平,软骨损伤灶内SDF-1表达量上调是吸引骨髓干细胞归巢的可能机制之一,通过调节基质细胞源性因子1及其受体CXCR4对MSCs的趋化作用,可望调控干细胞向靶组织的趋化聚集量,达到治疗目的。

Expression of stromal cell-derived factor-1 after articular cartilage injury

BACKGROUND: Studies have demonstrated that stromal cell-derived factor-1 (SDF-1) can influence the migration and aggregation of bone marrow mesenchymal stem cells (BMSCs).OBJECTIVE: To observe the expression of SDF-1 at lesion regions at different time after cartilage injury and to investigate the correlation between SDF-1 expression and BMSCs migration. METHODS: Rabbits models of articular cartilage injury were established. Focal osteochondral lesions were collected 2, 5, 7, 10, 14 and 28 days after injury. The influence of SDF-1 expression on the migration of BMSCs and chondrocytes was observed. RESULTS AND CONCLUSION: SDF-1 expression was significantly increased and peaked at the seventh day (P < 0.05). BMSCs migrated toward articular cartilage injury tissue, while they were significantly inhibited by the inhibitor of CXCL4. SDF-1 expression increases in the early phase after articular cartilage injury, and plays an important role in chemoattracting MSCs to injured lesions.