组织工程修复软骨基质蛋白聚糖代谢的初步探讨

Research on matrix proteoglycan turnover of tissue engineering repaired cartilage

目的检测软骨修复组织中蛋白聚糖相关代谢指标,初步探讨在软骨修复过程中基质蛋白聚糖的代谢变化以及基质金属蛋白酶(matrix metalloproteinases,MMPs)和蛋白聚糖酶(aggrcanases)的作用。方法松质骨骨基质明胶(bone matrix gelatin,BMG)复合同种异体软骨细胞构建组织工程化软骨,体内植入修复兔膝关节骨软骨缺损。术后6个月取材检测蛋白聚糖合成表位3-B-3(-)、MMPs、MMPs裂解表位BC-4以及aggrcanases裂解表位BC-13的表达情况。结果在修复组织中,蛋白聚糖合成表位3-B-3(-)表达增加,MMPs及其裂解表位BC-4表达减低,而aggrcanases裂解表位BC-13表达阴性。结论利用蛋白聚糖合成表位3-B-3(-)、MMPs、BC-4、BC-13的表达情况可以初步了解修复软骨组织中蛋白聚糖的代谢变化,修复软骨组织蛋白聚糖的合成大于分解,MMPs在兔关节修复软骨基质蛋白聚糖的基础代谢和重塑中具有重要作用。

Objective To examine matrix proteoglycan metabolic markers and probe into the turnover of matrix proteoglycan and enzyme-mediated role of matrix metalloproteinases （MMPs） and aggrecanases in reparative tissues with tissue engineering cartilage. Methods Tissue-engineered cartilage was constructed by cancellous bone matrix gelatin （BMG） with allogeneic chondrocytes in vitro for 2 weeks, then implanted to repair osteochondral defects of rabbit knee joint. Samples were obtained 6 months later to explore the expressions of 3-B-3（-） epitope, MMPs, MMP-generated epitope BC-4 and aggrecanases-generated epitope BC-13. Results In repaired tissues, the expression of 3-B-3 （-） epitope increased, but that of MMPs and MMP-generated epitope BC-4 reduced. There was no expression of aggrecanases-generated epitope BC-13. Conclusion Expressions of 3-B-3（-）, MMPs, BC-4 and BC-13 can help probe into the matrix proteoglycan turnover in reparative cartilage tissues. Anabolism exceeds catabolism in the repaired tissues. MMPs play an important role in the conservative baseline turnover of proteoglycan and remodeling of the graft tissues.