Functional biomedical polymers for corneal regenerative medicine

Recent progress in biomedical polymer science has greatly contributed to rapid development of corneal regenerative medicine. In the past decades, scientists have achieved several major breakthroughs in corneal tissue reconstruction. Studies regarding the findings of core-and-skirt keratoprostheses for visual rehabilitation, biosynthetic tissue replacements for corneal transplantation, and thermo-responsive cell-detachable substrates for corneal cell sheet engineering have been reported by several groups of investigators. This brief overview focuses on the contributions of functional polymers in the applications of corneal regenerative medicine. The keratoprosthetic devices developed by our group using heterobifunctional silicone rubber membranes grafted with different bioactive functional groups showed promising results in animal studies. In addition, the fabrication and transplantation of bioengineered human corneal endothelial cell sheets by utilizing the functional biomedical polymers such as poly(N-isopropylacrylamide) and gelatin are discussed, especially for the significance of gelatin in the development of a potential intraocular delivery system for cell sheet grafts.