Evaluating the Phagocytosis of Diseased Photoreceptor Outer Segments by Retinal Pigment Epithelial Cells in Age-Related Macular Degeneration

Abstract

Age-related macular degeneration (AMD), the leading cause of blindness in the elderly, is characterized by the death of photoreceptors and the retinal pigment epithelium (RPE). One of the main functions of the RPE is to phagocytose photoreceptor outer segments (POS) daily. While lipids in POS are used for energy production in the RPE, this process also produces toxic byproducts that cause oxidative damage. This study used induced pluripotent stem cells (iPSC) differentiated into RPE from a human donor without AMD (n = 1) to investigate whether photoreceptor disease state has an effect on the POS uptake. Results show that POS uptake is not dependent on AMD presence, but the uptake is POS donor specific.