Isolation and Comparative Transcriptome Analysis of Human Fetal and iPSC-Derived Cone Photoreceptor Cells

Abstract

Summary: Loss of cone photoreceptors, crucial for daylight vision, has the greatest impact on sight in retinal degeneration. Transplantation of stem cell-derived L/M-opsin cones, which form 90% of the human cone population, could provide a feasible therapy to restore vision. However, transcriptomic similarities between fetal and stem cell-derived cones remain to be defined, in addition to development of cone cell purification strategies. Here, we report an analysis of the human L/M-opsin cone photoreceptor transcriptome using an AAV2/9.pR2.1:GFP reporter. This led to the identification of a cone-enriched gene signature, which we used to demonstrate similar gene expression between fetal and stem cell-derived cones. We then defined a cluster of differentiation marker combination that, when used for cell sorting, significantly enriches for cone photoreceptors from the fetal retina and stem cell-derived retinal organoids, respectively. These data may facilitate more efficient isolation of human stem cell-derived cones for use in clinical transplantation studies. : Welby et al. define a cone-enriched gene signature within a human fetal L/M-opsin cone population, which is used as a baseline reference to demonstrate similar cone gene expression between bona fide and stem cell-derived L/M-opsin cone cells. Furthermore, profiling of cell surface molecules in human fetal cones led to the generation of a cluster of differentiation marker panel, which provides enrichment of fetal and stem cell-derived cones. Keywords: retinal dystrophies, cone photoreceptor cells, transcriptome, human pluripotent stem cells, retinal organoids, cell surface markers, cell transplantation therapy