Use of a silk fibroin-chitosan scaffold to construct a tissue-engineered corneal stroma.

Purpose: To construct a scaffold using silk fibroin (SF) and chitosan (CS) that could replace the corneal stroma with the biological characteristics of the scaffold materials still intact.

Methods: To develop an organotypic corneal stroma, SF and CS were chosen to synthesise the tissue-engineered bioscaffold. We cultured primary rabbit corneal epithelial cells and corneal stromal cells in vitro. Keratocytes were used to assess cytotoxicity on SF-CS (SFCS) blends, which was determined by a Cell Counting Kit-8 assay. The corneal lamellar scaffolds were developed with sequential culture techniques to form cell-scaffold constructs. Implantation was tested in 15 New Zealand White rabbits. The corneal substitutes were analysed by light and electron microscopy.

Results: The reconstructed lamellar cornea was comparable to native tissue, with high levels of K3/12 expression in the corneal epithelial cells and vimentin in the stromal cells; moreover, the morphology and the position of the cells could be distinguished by histological methods. There was no sign of any immune reaction in or around the transplanted discs 12 weeks after implantation.

Conclusion: A SFCS scaffold might be a suitable blend for corneal tissue engineering.