Avaliação da adesão, proliferação e diferenciação endotelial de células-tronco humanas cultivadas em nanofibras de polihidroxibutirato

Abstract

Tissue engineering is a field of regenerative medicine based on the association of cell culture in structural matrices and the incorporation of signaling molecules, targeting tissue regeneration. Despite its enormous potential, this strategy faces a major challenge concerning the maintenance of cell viability after the implantation of the constructs. The lack of a functional vasculature within the implant compromises the nutrition and removal of metabolites by cells, which can lead to implant failure. In this context, our research group is trying to create a new strategy for enhancing vascularization in tissue engineering, especially for bone tissue. The aim of this project is to establish a culture of human adipose tissue derived stem cells (hASC) in order to evaluate the biocompatibility of nanofiber meshes derived from polyhydroxybutyrate (PHB) and its copolymer poly-3-hydroxybutyrate-co-3- hydroxyvalerate (PHB-HV), and to promote the differentiation of stem cells into endothelial cells. Through in vitro assays, it was demonstrated that PHB/PHB-HV nanofiber meshes is biocompatible with stem cells isolated from human adipose tissue, and that it promotes cell adhesion, cell viability and proliferation. When implanted in vivo, the PHB/PHB-HV nanofiber meshes did not induce a high inflammatory response and did not affect the function of tissues in the region of the implant. Moreover, when cultured with endothelial differentiation medium, the hASC expressed endothelial markers. Taken together, the data presented above allow to suggest that it would be possible to use hASC derived differentiated cells cultured in PHB/PHB-HV nanofiber meshes to enhance the vascularization of tissue-engineered grafts.