Collagen‐immobilized poly (vinyl alcohol) as an artificial cornea scaffold that supports a stratified corneal epithelium

Abstract The cornea is a transparent tissue of the eye, which is responsible for the refraction of incoming light. Both biological corneal equivalents and synthetic keratoprostheses have been developed to replace donor tissue as a means to restore vision. However, both designs have drawbacks in terms of stability and biocompatibility. Clinically available synthetic devices do not support an intact epithelium, which poses a risk of microbial infection or protrusion of the prosthesis. In the present study, type I collagen was immobilized onto poly(vinyl alcohol) (PVA‐COL) as a possible artificial cornea scaffold that can sustain a functional corneal epithelium. Human and rabbit corneal epithelial cells were air‐lift cultured with 3T3 feeder fibroblasts to form a stratified epithelial layer on PVA‐COL. The epithelial sheet expressed keratin 3/12 differentiation markers, the tight junction protein occludin, and had characteristic microvilli structures on transmission electron microscopy. Functionally, the stratified epithelium contained normal glycogen levels, and an apical tight‐junction network was observed to exclude the diffusion of horseradish peroxidase. Furthermore, the epithelium‐PVA‐COL composite was suturable in the rabbit cornea, suggesting the possibility of using PVA‐COL as a biocompatible material for keratoprosthesis. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006