三维平行胶原支架促进肌腱样胞外基质形成的作用

Three-dimensional parallel collagen scaffold promotes tendon extracellular matrix formation

目的：探讨三维平行胶原支架对肌腱来源干细胞形态、排列及细胞外基质形成的影响。方法：应用单向冰冻技术制备三维平行胶原支架，应用传统冻干技术制备三维紊乱胶原支架。通过体外种植肌腱来源干细胞及皮下支架种植，观察不同三维结构对细胞形态、排列及细胞外基质形成的影响。结果：三维平行胶原支架呈现出三维平行的结构。种植在三维平行胶原支架上的细胞显示出纺锤样的肌腱细胞形态，同时细胞沿着胶原支架纤维方向排列，在第七天时形成了致密的细胞层；三维紊乱胶原支架上的细胞显示出多形性，随意分布在各个胶原支架片上。皮下种植实验中，2周后均有来自宿主的成纤维样细胞迁移进入支架，三维平行胶原支架中主要为细长的成纤维样细胞，细胞沿着支架方向排列；而在三维紊乱支架的细胞大多为椭圆形的，且分布没有一定的方向性。结论：平行的三维结构诱导细胞变得细长，促进细胞平行排列，同时促使形成的细胞外基质沿平行方向分布。该研究结果可以为理想的肌腱组织修复的支架构造提供参考和借鉴。

Objective： To investigate the effects of three-dimensional parallel collagen scaffold on the cell shape, arrangement and extracellular matrix formation of tendon stem cells. Methods： Parallel collagen scaffold was fabricated by unidirectional freezing technique, while random collagen scaffold was fabricated by freeze-drying technique. The effects of two scaffolds on cell shape and extracellular matrix formation were investigated in vitro by seeding tendon stem/progenitor cells and in vivo by ectopic implantation. Results： Parallel and random collagen scaffolds were produced successfully. Parallel collagen scaffold was more akin to tendon than random collagen scaffold. Tendon stem/progenitor ceils were spindle-shaped and unified orientated in parallel collagen scaffold, while cells on random collagen scaffold had disorder orientation. Two weeks after ectopic implantation, cells had^nearly the same orientation with the collagen substance. In parallel collagen scaffold, cells had parallel arrangement, and more spindly cells were observed. By contrast, cells in random collagen scaffold were disorder. Conclusion： Parallel collagen scaffold can induce cells to be in spindly and parallel arrangement, and promote parallel extracellular matrix formation; while random collagen scaffold can induce cells in random arrangement. The results indicate that parallel collagen scaffold is an ideal structure to promote tendon repairing.