Fig. 7

Low-grade peripheral inflammation impairs microglial phagocytosis of Aβ in App^NL-G-F mice. a Representative images of IBA1 and 6E10 staining in hippocampus and cortex. The dotted circle shows the border of Aβ plaques. Scale bar: 20 μm. b Quantification of the IBA1⁺ microglia within the Aβ plaque surface. Hippocampus (left); cortex (right) (n = 5–6; each symbol represents the average from 4–6 plaques in one mouse). c Quantification of the percentage of internalized Aβ in the hippocampus (left graph) and cortex (right) (n = 5–6). d Representative images of IBA1, 6E10 and CD68 staining in hippocampus and cortex. Arrow points to the CD68⁺ microglia. Scale bar in hippocampus: 100 μm and 20 μm (insert); Scale bar in cortex: 20 μm. e Quantification of CD68⁺ microglia (n = 5) in hippocampus (left two graphs) and cortex (right two graphs). f Representative images of relationship between microglial morphology and its distance to Aβ deposition. Scale bars: 20 µm. g Imaris-based quantification of cell morphology of IBA1⁺ microglia in hippocampus. Co-staining of IBA1, CD68 and 6E10 was performed on 5 µm paraffin sections. Each symbol represents the average in one cell and 10–15 cells are analyzed per mouse (n = 4–5). Mean ± SEM, two-way ANOVA Bonferroni’s post hoc test for multiple comparisons (b, c, e), nonparametric Mann–Whitney U test g. *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001