EVs in the retina
Shining light on extracellular vesicles
DOI: https://doi.org/10.47184/tev.2023.01.05 The present review presents the current knowledge on extracellular vesicle biology in the retina, a highly structured part of the central nervous system that is at the same time easily accessible. Numbers of publications in the field are rapidly rising, but most studies focus on extracellular vesicles as biomarkers for retinal diseases or as putative therapeutic targets. However, rather little has been done so far to elucidate the physiological functions of EVs in the retina. Even though it is clear that all the characteristic functions of EVs such as cell-cell communication, waste removal, extracellular matrix turnover, immune modulation etc. are of extreme importance in retinal tissue with its enormous metabolic turn over and the need to orchestrate broad adaptation to different conditions such as light and dark with as little disturbance of the light path as possible.
retina, RPE, Müller glia cells, photoreceptors, extracellular vesicles
Introduction to the retina
Sight is the dominant sense in humans, and the ability to see has a great impact on leading a socially and economically independent life. The dioptric apparatus of the eye focuses light from the surrounding onto the light-sensitive retina in the back of the eyeball. The retina consists of the retinal pigment epithelium (RPE) and the neuroretina. The retina is part of the central nervous system, having derived from invaginations of the anterior neuroectoderm during embryogenesis [1]. It is specialized to convert light into electrical signals that are transmitted to the brain via the optic nerve. The tissue is distinctly structured into three nuclear layers separated by two synaptic (plexiform) layers (Fig. 1).
