Fig. 3

Effect of LPS on microglia/macrophage numbers in the presence or absence of endothelial Tlr4. Representative dot plots of CD11b^pos populations (A, B left panels) gated as CD11b^posCD45^low/neg microglia and CD11b^posCD45^hi monocyte-derived macrophages (A, B right panels) in naïve and LPS-challenged C57BL/6J and Tek^Cre−posTlr4^loxP/loxP mice, respectively. Quantification of CD45^low/neg microglia and CD45^hi macrophages expressed as a percentage of the total number of live cells in the samples (C, D) revealed an increase of both populations after the LPS challenge in C57BL/6J mice but not in Tek^Cre−posTlr4^loxP/loxP mice (n = 5 mice per genotype and experimental group). The data were analyzed separately for each genotype with 2-tailed unpaired t-test (***p < 0.001). Representative images of retinal sections stained with Iba-1 and ICAM-1 in naïve (E, G, I) and LPS-challenged (F, H, J) C57BL/6J, Tek^Cre−negTlr4^loxP/loxP and Tek^Cre−posTlr4^loxP/loxP mice, respectively. ICAM-1 immunoreactivity was detected in LPS-challenged C57BL/6J and Tek^Cre−negTlr4^loxP/loxP mice but not in Tek^Cre−posTlr4^loxP/loxP mice. Scale bars: 200 μm. GCL Ganglion cells layer; INL inner nuclear layer; IPL inner plexiform layer; ONL outer nuclear layer; OPL outer plexiform layer