RPE Phagocytosis

Abstract

The retinal pigment epithelium (RPE) forms a polarized monolayer located between the photoreceptors of the retina and Bruch’s membrane that fulfills numerous functions in support of the neural retina’s function and integrity. One of its most important tasks is the diurnal phagocytosis and degradation of spent photoreceptor outer segment fragments. In this chapter we first introduce the physiology of photoreceptor outer segment renewal to which RPE phagocytosis contributes. We then compare experimental methods to analyze RPE phagocytosis and review known molecular mechanisms of the RPE phagocytic machinery. Finally, we summarize how defects in the RPE phagocytic process contribute to retinal diseases and highlight current aspects of research.