Macrophages of the Human Eye Come into Focus

Article: Macrophages of the Human Eye Come into Focus
Source: The Scientist
Published: March 1, 2021

Macrophages are immune cells present in all ocular tissues. On the surface of the retina they look and act like microglia, the "sentinels of the central nervous system." The present study using ocular coherence tomography (OCT) and adaptive optics (for enhanced image resolution) is the first to visualize these cells in real time in the eyes of living humans. The imaging technique allowed the researchers to pinpoint the location of retinal macrophages. For example, they discovered that in healthy eyes, the macrophages were densely distributed in the periphery of people's retinas and sparsely found near/at the fovea. The researchers hypothesized that the relative absence of macrophages at the fovea is related to retinal development, wherein photoreceptors migrate to what becomes the fovea, and the inner layers of the retina (such as the ganglion cell layer and nerve fiber layer) move aside for clearer light transmission. The role of macrophages is to clean up cellular debris from the inner retinal layers, which are absent at the fovea, and thus might explain macrophages' absence there. The researchers also found that in glaucoma, macrophages gather in areas of active disease. If these changes can be visualized and monitored over time, they could be an avenue of research as a biomarker of disease activity and severity.

My rating of this study: ⭐⭐⭐