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

许多与工作或运动有关的活动都可能导致软组织损伤，如扭伤、拉伤和肌腱炎。仅反复劳损就影响了大约15%的加拿大人(450万人)。全世界每年有3000万肌腱和韧带损伤，相当于至少3000亿美元的医疗总支出。在大多数情况下，这些伤害是通过康复治疗和疼痛管理来治疗的。然而，在肌腱断裂或广泛损伤的情况下，手术是唯一的选择，通常涉及从身体另一部分采集的肌腱片段或人造肌腱支架的移植。支架由脱细胞的胶原基组织或合成聚合物组装而成。第一种方案具有所需的胶原纳米结构，但力学性能较差，而第二种方案可以很容易地模拟肌腱的拉伸特性，但缺乏胶原。在这个项目中，我们想要设计和测试一种人造肌腱支架的性能，它符合肌腱固有的化学和力学特性，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3DBioFibR Inc.，这是一家总部位于哈利法克斯的初创公司，可以制造米长、亚微米直径的胶原/聚合物纤维，在聚合物在水中洗涤后留下连续的胶原纤维。我们将使用这项技术来组装大束亚微米胶原蛋白纤维，这些纤维与天然产品genipin交联，以增强它们的机械性能。纤维的结构和交联度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，这些细胞在分化为肌腱细胞时会发出荧光。细胞填充的支架还将进行结构和力学测试，以确定它们与天然肌腱的特性是否匹配。3DBioFibR将使用在该项目期间开发的方案和技术来生产各种肌腱支架原型，首先用于人造肌腱市场，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.