Amniotic Membrane– Poly (Vinyl Alcohol) Hybrid Polymer as an Artificial Cornea Scaffold

Abstract

Abstract: : Purpose: To investigate the biocompatibility of an amniotic membrane–immobilized polyvinyl alcohol (AM–i–PVA) hydrogel for use as an artificial cornea material. Methods: Rabbit limbal epithelial cells were air–lift cultured on AM–i–PVA discs with mitomycin–treated 3T3 feeder cells for 1 week. Differentiation of the epithelium and basement membrane formation were examined by immunohistochemistry for K3 (AE5), occludin, collagen IV and collagen VII. In an animal study, a 6 mm diameter AM–i–PVA disc was implanted into stromal pockets of Japanese white rabbits (n=12). An epithelial window (3 mm) was created over the implanted AM–i–PVA to allow epithelialization. The rabbits were followed for 1 month by slit lamp photography, followed by histological examination with HE stains. Results: Rabbit limbal cells formed 3 to 5 layers of keratin–3–positive epithelium on AM–i–PVA. Occludin (+) cells were observed lining the superficial epithelium, while both collagen IV and VII were observed in the basement membrane. Epithelization over implanted AM–i–PVA was complete within 2 weeks, with little inflammation or opacification of the hydrogel. Conclusions: AM–i–PVA supports a fully stratified, differentiated epithelium in vitro, and allows epithelial migration when transplanted in vivo.

Keywords: cornea: basic science • cornea: stroma and keratocytes • immunohistochemistry