Fig. 3

A1 Astrocytes are highly abundant in Tg-FDD. a Double-stained immunofluorescent images of complement component 3 (C3, red) and astrocytes (GFAP, green) in the hippocampus of WT and Tg-FDD mice. C3 and GFAP immunoreactivity overlay (Merge). b Quantification of C3⁺GFAP⁺ cell % from 3 regions per animal of the hippocampus of 4 WT and 3 Tg-FDD mice. c Quantification of % colocalization area from the hippocampus of 4 WT and 3 Tg-FDD mice. d Double-stained immunofluorescent images of complement component 3 (C3, red) and astrocytes (GFAP, green) in the cerebellum of WT and Tg-FDD mice. C3 and GFAP immunoreactivity overlay (Merge). e Quantification of C3⁺GFAP⁺ cells % from 3 regions per animal of the cerebellum of 4 WT and 3 Tg-FDD mice. f Quantification of % colocalization area from the cerebellum of 4 WT and 3 Tg-FDD mice. a and d are representative images of the brain regions of 9-month-old mice. Colocalization analysis (CC) was performed to determine pixel intensity correlation between C3 and GFAP signals. White pixels indicate colocalization between C3 and GFAP signal. Plot profiles of representative C3 and GFAP intensities show higher overlapping of C3 with GFAP in Tg-FDD mice in comparison with WT mice, indicating an increase of C3 positive astrocytes. Results are shown as the mean ± SEM of n = 3–4. Asterisks indicate significant differences, where **** p < 0.0001 by unpaired Student’s t test. Scale bar 100 μm