Differences in gene expression among AMD and non-AMD patients arise after initial fibroblasts are reprogrammed to iPSC and differentiation into RPE

Comparing fibroblasts and derived -iPSC and - RPE cells from human AMD and non-AMD donors Retinal pigment epithelium (RPE) generated from skin biopsies of donors with age-related macular degeneration (AMD) exhibit a disease phenotype and a distinct transcriptome compared to age-matched controls. We investigated whether similar differences existed in the skin fibroblasts and induced pluripotent stem cells (iPSCs) derived from them. Hierarchical cluster and principal component analyses revealed significant overlap in the transcriptome of fibroblasts of AMD and non-AMD donors. After reprogramming, iPSCs exhibited slight differences. In contrast, the transcriptome of RPE derived from AMD and normal donors segregated into two distinct clusters. Differences in the expression of specific genes that were evident between normal and AMD-derived RPE were not observed in fibroblasts or iPSCs. Mitochondrial respiration was reduced in RPE from AMD patients but not in fibroblast or iPSCs. RPE derived from AMD patients have a distinct transcriptome and phenotype compared to controls that is not observed in their corresponding skin fibroblasts or iPSCs. Fibroblasts, iPSC and derived RPE cells, from patients with four (4) advanced AMD and age matched three (3) non-AMD donors were used to survey the transcriptons of these samples with Affymetrix human Gene chips. Affymetrix Transcriptome Analysis Console software (Thermo Fisher Scientific) were used to process and analyze the data.