Fig. 4

Activation of microglia and analysis of the distribution in the retina. a The activation of microglia was analyzed as Iba1-positive cells per mm retina in naso-temporal cross-sections of the eye. After iOHT, a significant increase of microglia occurred in fellow and injured eyes (both p < 0.05) compared with control eyes. No significant changes were observed for Belimumab-treated animals. Significant values are indicated as follows: *p < 0.05. b–f Representative images of retinal cross-sections (×20 magnification) show the numbers and distribution of Iba1-positive cells (arrows) in diverse retinal layers in control (CTRL, b), fellow and injured eyes of iOHT group (c and d, respectively), and fellow and injured eyes of iOHT + Belimumab group (e and f, respectively). Magnifications of representative microglia show a transformation from non-activated ramified phenotype with long ramifications in controls (b) to an activated, amoeboid phenotype in injured eyes (d, f). g Percentile distribution of microglia cells in retinal layers are given for all groups. Data were normalized in relation to the difference of the total number of microglia between the groups. Significant values are indicated as follows: *p < 0.05, **p < 0.01. Abbreviations: GCL ganglion cell layer, IPL inner plexiform layer, INL inner nuclear layer, OPL outer plexiform layer, ONL outer nuclear layer, CHO choroid. Scale bar represents 100 μm