Isolation of Retinal Pigment Epithelial Cells from Guinea Pig Eyes

This protocol describes the isolation of cells of the retinal pigment epithelium (RPE) from the eyes of young pigmented guinea pigs for potential application in molecular biology studies, including gene expression analyses. In the context of eye growth regulation and myopia, the RPE likely plays a role as a cellular relay for growth modulatory signals, as it is located between the retina and the two walls of the eye, such as the choroid and sclera. While protocols for isolating the RPE have been developed for both chicks and mice, these protocols have proven not to be directly translatable to the guinea pig, which has become an important and widely used mammalian myopia model. In this study, molecular biology tools were used to examine the expression of specific genes to confirm that the samples were free of contamination from the adjacent tissues. The value of this protocol has already been demonstrated in an RNA-Seq study of RPE from young pigmented guinea pigs exposed to myopia-inducing optical defocus. Beyond eye growth regulation, this protocol has other potential applications in studies of retinal diseases, including myopic maculopathy, one of the leading causes of blindness in myopes, in which the RPE has been implicated. The main advantage of this technique is that it is relatively simple and once perfected, yields high-quality RPE samples suitable for molecular biology studies, including RNA analysis.