The poor healing ability of tendons as well as the limitations of currently used therapies have motivated tissue engineering (TE) strategies to develop living tendon substitutes. At the same time, the significant lack of knowledge on tendon homeostasis and disease mechanism trigger our interest to focus on the development of adequate 3D tissue models that can provide important insights for developing better and innovative therapies. Our team has been exploring the development of cell-laden 3D magnetically responsive systems that recapitulate key features of the native tissue and that can be remotely actuated both during in vitro culture and/or upon in vivo implantation, through the application of external magnetic stimuli. We are exploring conventional and innovative tools such as multimaterial 3D bioprinting to design magnetic responsive systems mimicking specific aspects of tendon tissue architecture, composition and biomechanical properties, which, combined with adequate stem cells, shall render appropriate behavioural instructions to stimulate the regeneration of tendon tissue. We have demonstrated that the magnetic stimulus of different intensities/frequencies can trigger tenonegic differentiation od hASCs and/or modulate inflammatory response of various cell types. Simultaneously, the 3D cell-laden magnetic system are also being as sophisticated 3D tissue models to unravel mechanisms behind tendon homeostasis and repair that shall support the base knowledge to establish rational design criteria for the biofabrication of living tendon substitutes offering the prospect of tendon regeneration as opposed to simple tissue repair.
Acknowledgments: Authors thank Hospital de Guimarães for tissue samples; FCT for project MagTT PTDC/CTM-CTM/29930/2017 and HORIZON 2020 for ERC CoG MagTendon (772817) and Twinning Project Achilles (810850)