Fig. 4

Diminished microglia activity in the retina. a Iba1 antibody (red) was used to label all phagocytes and combined with Tmem119 antibody (green) to distinguish between microglia (Tmem119⁺ and Iba1⁺) and recruited phagocytes (Tmem119⁻ and Iba1⁺). Active microglia/macrophages were identified by the co-localization of ED1 (green; arrows) and Iba1. b The number of Iba1⁺ cells was increased in the S100B group compared to both controls. Minocycline treatment reduced the S100B effect significantly. c The number of microglia (Tmem119⁺ and Iba1⁺) was upregulated in the S100B group compared to the naïve and PBS group. Both minocycline treatments significantly reduced this upregulation. d The number of phagocytes (Tmem119⁻ and Iba1⁺) was similar in all groups. e Also, higher active microglia/macrophage counts were noted in the S100B group in contrast to both control groups. ED1⁺ and Iba1⁺ cell numbers in the minocycline groups were reduced. Abbreviations: GCL: ganglion cell layer, IPL: inner plexiform layer, INL: inner nuclear layer, OPL: outer plexiform layer, ONL: outer nuclear layer. Scale bar: 20 μm, n = 6/group, ***p < 0.001 vs. naïve group, ^##p < 0.01, ^###p < 0.001 vs. PBS group, ^¥¥p < 0.01, ^¥¥¥p < 0.001 vs. S100B group