Fig. 2

Treg administration reduces number of activated microglia in the dentate gyrus. A Representative images of Iba1 positive-microglia (red) and 6E10-positive Aβ plaques (green) in the dentate gyrus (DG) of WT-WT, 5xFAD-WT, 5xFAD-Rag2KO and Treg-treated 5xFAD-Rag2KO (n = 6 per group, sex balanced). B Quantification of the number of Iba⁺ microglia in the DG; while number of Iba1⁺microglia was increased in 5xFAD-WT mice, compared to WT-WT, lack of adaptive immune system in 5xFAD-Rag2KO and subsequent Treg administration had no effect on the number of Iba1⁺ microglia. C Quantification of the number of Iba1⁺ microglia within 20 μm of the plaque surface; Treg administration reduced number of plaque- associated Iba1⁺ microglia. D Representative images of CD68-positive activated microglia (red) and 6E10-positive Aβ plaques (green) in the dentate gyrus. Quantification of CD68-positive activated microglia in the DG (E) and CD68-positive microglia within 20 μm of the plaque surface (F), revealed decreased number of total and plaque-associated CD68⁺ microglia in 5xFAD-Rag2KO following Treg administration. Numbers shown as averages ± SEM with one-way ANOVA. *p < 0.05, **p < 0.01, ***p < 0.001 and ****p < 0.0001. Scale bar, 100 μm