Single-cell transcriptomics of the human retinal pigment epithelium and choroid in health and macular degeneration

AP Voigt, K Mulfaul, NK Mullin… - Proceedings of the …, 2019 - National Acad Sciences
Proceedings of the National Academy of Sciences, 2019National Acad Sciences
The human retinal pigment epithelium (RPE) and choroid are complex tissues that provide
crucial support to the retina. Disease affecting either of these supportive tissues can lead to
irreversible blindness in the setting of age-related macular degeneration. In this study, single-
cell RNA sequencing was performed on macular and peripheral regions of RPE-choroid
from 7 human donor eyes in 2 independent experiments. In the first experiment, total
RPE/choroid preparations were evaluated and expression profiles specific to RPE and …
The human retinal pigment epithelium (RPE) and choroid are complex tissues that provide crucial support to the retina. Disease affecting either of these supportive tissues can lead to irreversible blindness in the setting of age-related macular degeneration. In this study, single-cell RNA sequencing was performed on macular and peripheral regions of RPE-choroid from 7 human donor eyes in 2 independent experiments. In the first experiment, total RPE/choroid preparations were evaluated and expression profiles specific to RPE and major choroidal cell populations were identified. As choroidal endothelial cells represent a minority of the total RPE/choroidal cell population but are strongly implicated in age-related macular degeneration (AMD) pathogenesis, a second single-cell RNA-sequencing experiment was performed using endothelial cells enriched by magnetic separation. In this second study, we identified gene expression signatures along the choroidal vascular tree, classifying the transcriptome of human choriocapillaris, arterial, and venous endothelial cells. We found that the choriocapillaris highly and specifically expresses the regulator of cell cycle gene (RGCC), a gene that responds to complement activation and induces apoptosis in endothelial cells. In addition, RGCC was the most up-regulated choriocapillaris gene in a donor diagnosed with AMD. These results provide a characterization of the human RPE and choriocapillaris transcriptome, offering potential insight into the mechanisms of choriocapillaris response to complement injury and choroidal vascular disease in age-related macular degeneration.
National Acad Sciences