Fig. 1
Age-related increase of microglia in inner plexiform layer (IPL), outer plexiform layer (OPL) and subretinal space (SRS). A Model of retinal cross sections showing changes in distribution and location of microglia between young/healthy and aged/injured retinas. B Representative images and number of P2RY12 + cells in IPL of 3-month, 18-month and > 30-month-old mice. C Representative max projected Z stacks images and number of P2RY12 + cells in OPL of 3-month, 18-month and > 30-month-old mice. D Representative RPE/choroidal flat mounts of 3-month, 18-month and > 30-month-old mice. P2RY12 + cells counted with ImageJ are labeled in red. High magnification zoom-outs stained with f-actin (red) and P2RY12 (white). E Total number of P2RY12 + cells on 3-month, 18-month and > 30-month RPE/choroid flat mounts. F Representative images of P2RY12 + cells in OPL of 3-month, 18-month and > 30-month-old mice. The 4 longest processes (purple) per image were traced and the process length measured using the NeuronJ plugin for ImageJ. G Maximal processes length of P2RY12 microglia in OPL at 3-month, 18-month and > 30 months. H Representative images of P2RY12 + cells in SRS of 18-month and > 30-month-old mice. The 4–5 longest processes (purple) per image and the process length was traced and measured using the NeuronJ plugin for imagej. I Maximal processes length of SRS P2RY12 microglia at 18-month and > 30 months. The number of P2RY12 cells were too rare at 3-months to quantify process length. n = 10 neural retinas per group, n = 10 RPE flat mounts for 3 months and 18 months, n = 2 RPE flat mounts for > 30 months, one-way anova with Tukey’s multiple comparison test. *P ≤ 0.05; **P ≤ 0.01; ****P ≤ 0.0001; ns, not significant. B, F and H scale is 50 µm, D scale is 20 µm