应用组织工程化肌腱修复兔跟腱缺损

Repair of rabbit Achilles's tendon defect with tissue engineered tendon

目的:由于肌腱来源受限及人工代用品力学性能差等缺点限制了临床肌腱损伤的修复,为此探索组织工程化肌腱修复兔跟腱缺损的可行性,以期为肌腱修复提供实验依据。方法:实验于2000-08/2001-12在第一军医大学中心实验室完成。30只新西兰白兔分为2组:人发角蛋白(HHK)组:用HHK材料修复兔跟腱缺损;组织工程化肌腱组:骨髓间充质干细胞(MSCs)与HHK在模拟微重力条件下形成细胞-材料复合体,修复兔跟腱缺损。采用组织学和免疫组织化学方法观察术后3,6和12周损伤肌腱的修复情况。利用分子生物学手段检测新生肌腱Ⅰ型胶原mRNA表达。结果:扫描电镜下可见MSCs-HHK组织工程化肌腱上有大量梭形的MSCs贴附生长,细胞平行排列,细胞间有突起相连。与HHK组相比,组织工程化肌腱组新生肌腱组织Ⅰ型胶原mRNA呈较高表达,腱细胞增生活跃,胶原纤维更为成熟。结论:在模拟微重力条件下以MSCs为种子细胞,HHK为支架材料构建的组织工程化肌腱能够有效地修复兔跟腱缺损。

AIM:The limited source of tendon and the poor mechanical properties of the art ificial substitute confine the repair of clinical Achilles's tendon defect.There fore,to probe into the feasibility of repair rabbit Achilles's tendon defects wi th the tissue engineered tendon so as to provide the experiment basis for the re pair of Achilles's tendon. METHODS:The experiment was completed in the Center Laboratory of First Milita ry Medical University from August 2000 to December 2001.Totally 30 New Zealand w hite rabbits were divided into 2 groups: human hair keratin(HHK) group and tissu e engineered tendon group. In the HHK group:repairing the rabbit Achilles's tend on with HHK materials;In the tissue engineered tendon group: tissue engineered t endons were complex construction of bone marrow mesenchymal stem cells(MSCs) and HHK under simulated micro gravity in the rotary cell culture system.The struct ures of regenerative tendons in the two groups at 3rd,6th and 12th weeks after o peration were examined with histological and immunohistochemical methods and the type I collagen gene expression of the regenerative tendons were examined with molecular biological method. RESULTS:Scanning electron microscopic observation revealed that the MSCs adher ed and grew well on the surface of HHK and arranged in parallel under simulated microgravity. Adjacent MSCs connected each other with their processes.Compared w ith that of the HHK group, higher expression of type I collagen gene, more cell proliferation and more mature looking collagen fiber bundles in the tissue engi neered tendon group have been detected. CONCLUSION:Transplantation of the tissue engineered tendon that culture expand ed MSCs in combination with HHK under simulated microgravity can serve as an exa mple of a cell based treatment for regeneration in tendon defects.