A Living Biological Bandage for management of corneal injuries

Abstract

Purpose : A large percentage of corneal opacifications are caused by chemical injuries, for which current conventional treatment strategies are costly, and may even result in complications, including immunological rejection after transplantation or glaucoma. Cell sheet engineering via an Aqueous-Two-Phase-System (ATPS) is an emerging technique which may act as a more economical alternative to construct an epithelial bandage for healing of corneal epithelial wounds. The purpose of this study is to increase the rate of re-epithelialisation in corneal epithelial defects, using a cellular construct that is delivered to the injured ocular surface with the help of a contact lens. We investigate the properties of the corneal epithelial cell sheet, and quantify the efficacy of the cell sheet therapy via an in vitro chemical injury model and an ex vivo porcine cornea model. Methods : A primary human corneal epithelial cell line was used for in vitro experiments. The cell sheet was formed between a liquid-liquid interface, which was formed with a Poly(ethylene glycol)(PEG)-rich layer on top and a Dextran(DEX)-rich layer at the bottom. The cell density used for constructing the cell sheet, as well as the time for incubation, were optimised. We carried out in vitro tests to investigate the properties of the cell sheet as well as its viability in the ATPS components. We also measured the efficacy of cell sheet transplantation in healing a chemical injury wound on a Transwell model. In addition, an ex vivo porcine cornea model was adopted to examine the integration, proliferation properties, and retention of the cell sheet on a de-epithelialised cornea. Results : Upon measuring the percentage area of defect on the in vitro chemical injury model on set time points throughout a 7 day observation period, we found the cell sheet to significantly reduce the time required for wound healing compared to the control group without transplantation performed. In addition, our ex vivo model illustrated strong adherence of the transplanted cell sheet on the de-epithelialised porcine cornea. Conclusions : Our current results illustrate potential for the ATPS cell sheet engineering technique to be used as a management strategy for ocular injuries. Future work points towards the conducting in vivo experiments to assess the efficacy and physiological outcomes of the cell sheet transplant method for wound repair. This is a 2021 ARVO Annual Meeting abstract.