Fig. 5
Representative images of immunohistochemistry targeting Iba1 demonstrating distinct microglia/macrophage morphologies within different retinal layers. Ramified microglia, characterized by long and thin cellular processes around a small, distinct soma, were mostly located within OPL and IPL of wild type (WT) mice. A ramified morphology indicates a non-activated, resting state (A, B), which is most abundant in the OPL and IPL of WT mice (H). Activation of microglia/macrophages in Glb1 knockout (Glb1−/−) mice leads to shortening and thickening of processes resulting in a spiky morphology and enlarged, more irregular cell bodies. Spiky Iba1-positive cells (C, E: arrow, G) were mostly detected in the OPL of Glb1−/− mice (I). Amoeboid microglia/macrophages display a roundish morphology with very short or even absent processes as well as an increased diameter of the soma (D, E: arrowhead, F). This phenotype is mostly detected in the IPL layers of Glb1−/− mice (J). Scale bars: 10 μm. Graphs display box and whisker plots. Significant differences between groups were detected by Kruskal-Wallis test followed by Dunn’s-Bonferroni procedure; *p ≤ 0.05; n = 5. IPL, inner plexiform layer; OPL, outer plexiform layer.
