title: Porous silk fibroin film as a transparent carrier for cultivated corneal epithelial sheets.
abstract: Biological carriers, such as the amniotic membrane and serum-derived fibrin, are currently used to deliver cultivated corneal epithelial sheets to the ocular surface. Such carriers require being transparent and allowing the diffusion of metabolites in order to maintain a healthy ocular surface. However, safety issues concerning biological agents encouraged the development of safer, biocompatible materials as cell carriers. We examined the application of porous silk fibroin films with high molecular permeability prepared by mixing silk fibroin and poly(ethylene glycol) (PEG), and then removal of PEG from the silk-PEG films. Molecular permeability of porous silk fibroin film is higher than untreated silk fibroin film. Epithelial cells were isolated from rabbit limbal epithelium, and seeded onto silk fibroin coated wells and co-cultured with mitomycin C-treated 3T3 fibroblasts. Stratified epithelial sheets successfully engineered on porous silk fibroin film expressed the cornea-specific cytokeratins K3 and K12, as well as the corneal epithelial marker pax6. Basement membrane components such as type-IV collagen and integrin β1 were expressed in the stratified epithelial sheets. Further more, colony-forming efficiency of dissociated cells was similar to primary corneal epithelial cells showing that progenitor cells were preserved. The biocompatibility of fibroin films was confirmed in rabbit corneas for up to 6 months. Porous silk fibroin film is a highly transparent, biocompatible material that may be useful as a carrier of cultivated epithelial sheets in the regeneration of corneal epithelium.
authors.affiliation: a Department of Ophthalmology and Cornea Center, Tokyo Dental College, Sugano 5-11-13, Chiba 272-8513, Japan; Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku, Tokyo 160-8582, Japan.
authors.forename: Kazunari
authors.initials: K
authors.lastname: Higa
authors.forename: Naomi
authors.initials: N
authors.lastname: Takeshima
authors.forename: Fumika
authors.initials: F
authors.lastname: Moro
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kawakita
authors.forename: Motoko
authors.initials: M
authors.lastname: Kawashima
authors.forename: Makoto
authors.initials: M
authors.lastname: Demura
authors.forename: Jun
authors.initials: J
authors.lastname: Shimazaki
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Asakura
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tsubota
authors.forename: Shigeto
authors.initials: S
authors.lastname: Shimmura
mesh_terms: D016475:3T3 Cells; D000650:Amnion / Q000502:physiology; D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis / Q000737:chemistry; D012831:Bombyx; D018920:Coculture Techniques; D019573:Epithelium, Corneal / Q000637:transplantation*; D005347:Fibroblasts / Q000502:physiology; D005349:Fibroins / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D051379:Mice; D010539:Permeability; D011092:Polyethylene Glycols / Q000737:chemistry; D016062:Porosity; D011817:Rabbits; D023822:Tissue Engineering / Q000379:methods; D054457:Tissue Scaffolds / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D011092:Polyethylene Glycols; D005349:Fibroins