Single-Eye Porcine Retinal Pigment Epithelium Cell Cultures—A Validated and Reproducible Protocol

Background: Age-related macular degeneration (AMD) is the leading cause of severe vision loss in industrialized nations. AMD models based on standardized optimized cell culture models are warranted. The aim of this study is to implement a standard operation protocol for the preparation of porcine retinal pigment epithelium (RPE) from pig eyes with cells from one eye designated for one culture, generating a genetic homology within one culture and genetic heterogeneity between cultures, thereby implementing a relevant in vitro model for AMD investigations. In addition, the use of pigs’ eyes from slaughterhouse waste material is an active measure to reduce animal experimentation in ophthalmological research. Methods: Primary porcine RPE cells were prepared, and cells from one eye were seeded into one well of a twelve-well polystyrene plate. They were cultured for 7, 14, and 28 days. Different post-mortem times (2, 4, and 6 h), coatings (collagen I, IV, Poly-d-Lysine, fibronectin, and laminin), and serum content of media (1%, 5%, and 10%) were tested. The success rate for confluence and survival was determined. At the different time points, cell number (trypan blue exclusion assay), confluence and morphology (microscope imaging), VEGF content of supernatants, and gene and protein expression, as well as tight junctions (fluorescence imaging), were examined. In addition, a baseline for RPE morphometry using CellProfiler software was established. Results: A post-mortem time of 4 to 5 h is most suitable. A coating with Poly-d-Lysine is recommended due to high success rates, the fastest confluence, the highest expression of RPE65, and suitable morphologic properties. The results for confluence, protein expression, and morphology showed that a reduction of 10% to 5% FBS is acceptable. Conclusion: A basic best practice protocol for the preparation of porcine single-eye cultures with optimized parameters was established and is provided.