A biomimetic three-layered compartmented scaffold for vascular tissue engineering

Tissue engineering of vascular grafts still presents several shortcomings. Aiming to vascular regeneration, we developed a biomimetic multilayered scaffold with a middle pivotal collagen lamina between two functionalized layers of poly-L-lactide by means of electrospinning technique, with oriented drug-delivery capacity for the differentiation of human mesenchymal stem cells seeded therein. Applying appropriate cytokines, the inner layer is able to act as a drug delivery system in order to generate a pro-angiogenic and anti-thrombotic environment and the outer one is used to induce the media and adventitia generation. Our findings are consistent with an adequate cell engrafting and a double type of differentiation in each side of the scaffold, in particular cells exhibited morphostructural changes resulting in the achievement of an endothelial-like phenotype in cells populating the inner side of the scaffold and SMA positivity with cell elongation resembling muscular phenotype in the cells of the outer layer. The proposed "smart" vascular bio-prosthesis will recapitulate the structure and microenvironment of native cardiovascular tissues. It could surmount many hurdles to clinical use and would be relevant for therapeutic applications in a variety of medical fields.