Design and fabrication of a novel bioreactor for the engineering of tendon/ligament-to-bone interfaces

In this work we present the design and development of a new bioreactor for supporting the regeneration of the enthesis, the area where the tendon or ligament insert into bone. Specifically, to optimize the proliferation, cell differentiation, and thereby the mechanical properties of a bioartificial construct, the bioreactor is designed to apply cyclic strains on a scaffold over a range of stress. The bioreactor was designed to meet several criteria. It allows applying precise control of the strain field on a scaffold. The hardware design guarantees real-time monitoring of the tensile stress applied to the scaffold and provides data to the user to perform mechanical characterization. It can be placed in standard incubators and provides a simple but effective scaffold clamping system. It ensures an airtight seal during the working phases to avoid contamination of the culture medium and provides a sterile environment during use. Finally, the developed software allows to select both pre-set or customizable stimulation cycles by setting traction frequency and test duration. All the critical specifications were met, so this work sets the stage for testing the proposed device with scaffolds developed in the framework of the TRITONE project, in order to support the biofabrication of autologous enthesis-like constructs.