Porcine Cornea Storage Ex Vivo Model as an Alternative to Human Donor Tissues for Investigations of Endothelial Layer Preservation

Purpose: Due to the growing shortage of human corneas for research, we developed a porcine cornea storage model with qualitative features comparable to human tissues.Methods: We established a decontamination procedure for porcine eye bulbs to ensure corneal storage at 31 degrees C to 35 degrees C for up to 28 days without contamination. We compared human and porcine corneas under hypothermic (2-8 degrees C) or culture (31-35 degrees C) conditions for central corneal thickness (CCT), corneal transparency, endothelialmorphology, endothelial cell density (ECD), and a novelmethod to quantifywhole endothelialmortality. We also examined portions of lamellar tissues consisting of Descemet's membrane and endothelial cells under the microscope after Alizarin red staining.Results: Our decontamination procedure reduced corneal contamination from 94% (control corneas without decontamination) to 18% after 28 days of storage at 31 degrees C to 35 degrees C. ECD, CCT, transparency, and morphology were significantly higher in porcine corneas than in human corneas at day 0. Nevertheless, the qualitative parameters of porcine and human corneas showed comparable trends under both investigated storage conditions for up to 14 days.Conclusions: The presented corneal storage model provides a reliable alternative to human tissues for preliminary corneal investigations.Translational Relevance: The porcine cornea storagemodel can be used to investigate the efficacy and safety of new media, substances, or storage conditions. Furthermore, themethod developed to assess the percentage of endothelialmortality is tissue conservative and can be used in eye banks to monitor endothelial mortality during storage of tissues intended for transplantation.