Design and performance of an artificial tendon scaffold based on collagen/polymer fibres

许多活动，工作或运动相关，可导致软组织损伤，如扭伤，拉伤和肌腱炎。仅重复性劳损就影响了大约15%的加拿大人（450万人）。全世界每年发生3000万例肌腱和韧带损伤，这意味着医疗保健支出总额至少为3000亿美元。在大多数情况下，这些损伤通过康复治疗和疼痛管理来治疗。然而，在肌腱断裂或大面积损伤的情况下，手术是唯一的选择，通常需要从身体的另一部分移植肌腱片或人工肌腱支架。这种支架由去细胞的胶原组织或合成聚合物组装而成。第一种选择具有所需的胶原蛋白纳米结构，但机械性能较差，而第二种选择可以很容易地模拟肌腱的拉伸性能，但缺乏胶原蛋白。在这个项目中，我们希望设计和测试一种人造肌腱支架的性能，该支架与肌腱的天然化学和机械特性相匹配，并支持间充质祖细胞向肌腱细胞的分化。我们的合作伙伴是3dbiofiber公司，这是一家总部位于哈利法克斯的初创公司，可以制造一米长、亚微米直径的胶原/聚合物纤维，在聚合物被水冲走后，会留下连续的胶原纤维。我们将使用这项技术来组装大束的亚微米胶原纤维，这些胶原纤维与天然产物genipin交联，以提高它们的机械性能。纤维的结构和交联含量将通过原子力显微镜和拉曼光谱进行评估。获得的支架将被消毒，并用于培养小鼠间充质祖细胞，当它们分化成肌腱细胞时，会发出荧光。细胞填充支架也将进行结构和机械测试，看看它们与天然肌腱的性能是否匹配。3DBioFibR将利用在该项目中开发的方案和技术，首先为人造肌腱市场生产各种肌腱支架原型，然后用于开发基于干细胞的肌腱再生疗法。

Many activities, work or exercise-related, can lead to soft tissue injuries such as sprains, strains and tendonitis. Repetitive strain injuries, alone, affect around 15% of Canadians (4.5 million people). Worldwide there are 30 millions tendon and ligament injuries occurring annually that represent a total Healthcare expenditure of at least $300 billions. In most cases these injuries are treated through rehabilitation therapies and pain management. However, in case of tendon rupture or extensive damage, surgery is the only option and often involves grafting of a tendon piece harvested from another part of the body or an artificial tendon scaffold. The scaffolds are either assembled from pieces of decellularized collagen-based tissue or from synthetic polymers. The first option has the required collagen nano-architecture but the mechanical performance is poor whereas the second option can easily mimic tendon tensile properties but lacks collagen. In this project we want to design and test the performance of an artificial tendon scaffold that matches the native chemical and mechanical properties of a tendon and supports the differentiation of mesenchymal progenitor cells into tendon cells. Our partner is 3DBioFibR Inc, an Halifax-based start-up company that can fabricate meter long, submicron diameter, collagen/polymer fibres that leave behind a continuous collagen fibre after the polymer is washed away in water. We will use this technology to assemble large bundles of submicron collagen fibres that are cross-linked with a natural product, genipin, in order to enhance their mechanical properties. The structure and cross-linking content of the fibres will be assessed by atomic force microscopy and Raman spectroscopy. The obtained scaffolds will be sterilized and used to culture mouse mesenchymal progenitor cells engineered to fluoresce when they differentiate into tendon cells. The cell populated scaffolds will also be tested structurally and mechanically to see how well they match the properties of native tendons. 3DBioFibR will use the protocols and techniques developed during this project to produce various tendon scaffold prototypes first for the artificial tendon market and then for the development of a stem cell based tendon regeneration therapy.