Mechanical bioreactor for tissue-derived extracellular matrix scaffolds recellularization
AbstractTissue engineering applies the principles of engineering and life sciences towards the development of functional engineered tissue. The complexity involved in in vivo biological systems creates a need for bioreactors, which can closely mimic the cells microenvironment. Some cells are well known to have the ability to sense and respond to mechanical stimuli, and a certain level of control over cell growth and differentiation may be accomplished through stretch stimulation. This work involves design, development and implementation of a stretching device that induces uniaxial mechanical strain in recellularized native extracellular matrix scaffolds. The device structure was obtained by using the 3D printing technology, and cell stretching was accomplished via nut-spindle system. Porcine heart matrices, which served as mechanical support for the cells, were obtained by implementing an immersing decellularization protocol. The protocol’s effectiveness was verified through hematoxylin-eosin staining, and then a MTT cytotoxicity assay was performed. The latter brought out a satisfying result, showing cell viability percentage above 70%. The cell-stretcher test experiment involved 120 h, and included mechanical stimulation of a native extracellular matrix scaffold, seeded with Vero cells. Cell adhesion was verified with hematoxylin-eosin staining, while labeling the sample with fluorescein diacetate and propidium iodide showed the presence of metabolically active cells after mechanical stimulation.