Fig. 3

Activation and increased cell populations of macroglia and microglia in the retina post I/R. Representative images of Iba1- and GFAP-positive cells in uninjured (a), (c) and ischemic (b), (d) retinas. a, b Yellow inset boxes of selected Iba1⁺ microglia demonstrate morphological differences between senescent (i) and activated (ii) cellular states. c, d Morphological differences observed in GFAP⁺ cells following ischemia. Astrocytes and Müller cells display elongated processes extending through the layers of the retina in addition to thickened cell bodies present in the GCL and NFL. e, f Thresholding analysis based upon percent area of retina occupied was applied to determine changes in cell density. Microglial density (e) was significantly increased in ischemic retinas at all time points quantified compared with uninjured controls. Density of macroglia (f) trended upward on day 3 and was statistically significant at all time points measured thereafter. Mean ± SEM, n = 7 per group. *p < 0.05 **p < 0.01 ***p < 0.001 using students paired t-test between control and ischemic groups. GCL = Ganglion Cell Layer, INL = Inner Nuclear Layer, ONL = Outer Nuclear Layer