Desarrollo de modelos experimentales de prótesis de córnea humanizada autóloga

Resumen

Corneal regeneration is an essential step in the restoration of normal anatomy after debilitating diseases of the cornea. The objective on this doctorate project is to develop biomaterials that work as carriers for autologous pluripotent human cells, in order to promote their integration and regenerate the stroma in structurally weakened corneas. In a first step we analyzed the in vitro physical properties of 90μm‐thick grafts of polyethylacrylate (PEA) and decellularized human corneal stroma, as well as the ability of proliferation, infiltration and adhesion of human adipose tissue derived stem cells (ADASC) on them. In a second step we studied the in vivo behavior of these two types of implants with and without cellular colonization by a controlled and triple masked trial, using an experimental New Zealand rabbit model. The implants were introduced into manually dissected stromal pockets, and a complete follow up of 3 months was carried out, clinically analyzing the conjunctival injection, and the corneal transparency and vascularization. After euthanasia of the rabbits a histological and histochemical study of the corneas was conducted in order to evaluate the survival of ADASC and their differentiation into adult keratocytes. The PEA membranes with 10% hydroxyethylacrilate drastically reduced their extrusion rate and can be used as a scaffold for future models of keratoprosthesis. The decellularized human corneal sheets with subsequent recellularization showed an optimum biointegration in the corneal stroma in the absence of any inflammatory response, and allowed better survival and differentiation of stem cells as compared to the PEA membranes. This lamellar transplant model by decellularization with subsequent extraocular stem cell recellularization allows to obtain functionalized autologous lamellar grafts from allogeneic corneas.