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

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.