Fig. 7
From: Pathological changes induced by Alzheimer’s brain inoculation in amyloid-beta plaque-bearing mice
Microglial activation in ADbe and Ctrlbe-inoculated APPswe/PS1dE9 mice (8 mpi). Within each group, animals with high and low Iba1 staining were identified. Representative images of one animal with higher Iba1 levels showing abundant staining in the hippocampus (a) and perirhinal/entorhinal cortex (b). Animals with higher Iba1 levels displayed activated microglia characterized by beading with spheroidal swellings of the processes and enlarged cell body with dystrophic ramifications (c, arrows). Animals with lower Iba1 levels (d, e) displayed more cells with a highly ramified profile (f) consistent with a non-activated phenotype. Representative images of one animal with higher (g) or lower (h) CD68 staining in the hippocampus. Iba1 staining level was correlated with CD68 labelling in the perirhinal/entorhinal cortex (j). Similar levels of Iba1 (m) and CD68 (o) stained areas in the perirhinal/entorhinal cortex of Ctrlbe and ADbe animals (Mann Whitney's tests). Confocal microscopy showed Iba1-positive microglia (red) surrounding Aβ deposition stained by MXO4 (blue) (i). The Iba1-positive microglial load surrounding the Aβ plaques was similar in the different groups (k, Mann Whitney's test). Interestingly, synaptic density was positively correlated with microglial Iba1 (l) or CD68 (n) labelling in the perirhinal/entorhinal cortex (Spearman’s correlations). nCtrl = 15, nAD1 = 15 (light pink), nAD2 = 20 mice (dark pink). Scale bar = 20 µm