Dysregulation in Retinal Para-Inflammation and Age-Related Retinal Degeneration in CCL2 or CCR2 Deficient Mice
Figure 3
TEM images of RPE/photoreceptor of different strains of mice.
A, an image from a 22-month old WT mouse showing RPE basal laminar deposits (asterisk). B, an image from 22-month old CCR2 KO mouse showing a photoreceptor outer segment (arrowhead) in parallel with RPE cells, multiple vacuoles (white arrows) in RPE cells and basal laminar deposits (asterisk). C, an image from a 22-month old CCL2 KO mouse showing multiple vacuoles in RPE cells (white arrows) and basal laminar deposits (asterisk). D, an image from a 24-month old CCL2 KO mouse showing multiple vacuoles and reduced melanin granules in degenerated RPE cells, basal laminar deposits (asterisk). E, an image from a 24-month old CCR2 KO mouse showing photoreceptor inner segment degeneration (black arrows), and a gap between RPE cells and photoreceptor outer segments. F, an image from a 20-month old CCL2 KO mouse showing photoreceptor inner segment degeneration (black arrows), reduced melanin granules in RPE cells and RPE basal laminar deposition (asterisk). G, an image from a 20-month old CCL2 KO mouse showing a patch of RPE atrophy, disorganised photoreceptor outer segments, a lack of choriocapillaris, and fibrotic tissues in the choroid (black asterisks). H and I, images from a 24-month old CCL2 KO mouse showing the loss of electron-dense materials in the cytoplasm, the loss of cytoplasm organelles and membrane, and a nucleus with reduced electron-dense materials in the RPE layer; choriocapillaris basal laminar deposition in the choroid; a layer of melanin granule-containing cells (block arrowheads) on top of the degenerated RPE cells with their process extending towards the photoreceptor outer segments. RPE, retinal pigment epithelia. (J), A confocal image of RPE/choroidal flatmount of a 24-month CCL2 KO mouse showing accumulation of macrophages/microglia at the site of RPE damage. RPE damages were highlighted with disorganised actins (phalloidin staining) and subretinal macrophages were labelled with Iba-1.