Fig. 5

Phagocytic activation of plaque-associated microglia is enhanced in mice overexpressing Prdx6 and attenuated in Prdx6 haplodeficient mice. Representative LSCM images of mature plaques co-labeled with X-34 (fibrillar core), anti-Aβ (HJ3.4 clone), anti-Iba1, and DRAQ5 (nuclear stain) in a, and with X-34, anti-Aβ, anti-CD68, and DRAQ5 in b evidencing direct relationship between Prdx6 gene dose and the number of periplaque microglia cells and expression of Iba1 and CD68 microglial activation markers. Shown are morphometric analyses of plaque-associated microglia number c, Iba1 plaque index (Iba1⁺ % plaque area) d, microglia barrier robustness (Iba1/X-34% co-localization) e, and CD68 phagosome plaque index (CD68⁺ % plaque area) f. Values in c through f represent mean (+SEM) from n = 26–35 randomly selected plaques per staining and per genotype. p < 0.0001 in c through f (ANOVA); *p < 0.05, **p < 0.01, and ****p < 0.0001 (Holm-Sidak’s post-hoc test). Scale bar: 10 μm in a and b