Figure 2. Loss of Syk in microglia negatively affects neuronal health and exacerbates AD-related behaviors in 5xFAD mice.
(A–F) Brains were harvested from 5xFAD SykΔMG mice and 5xFAD littermate controls at 5 months of age to evaluate neuronal health and cell death.
(A) The formation of dystrophic neurites surrounding plaques in the cortex was determined by staining for APP (blue) and Aβ using ThioS (pink).
(B) Quantification of APP+ puncta found within 15 and 30 μm of Aβ plaques from a total of ~40 plaques from 3 matching brain sections per mouse.
(C) Cortical sections were stained with AT8 (yellow) for phosphorylated tau (p-tau) puncta found within 15 μm of ThioS (pink)-stained Aβ plaques.
(D) Quantification of p-tau from a total of ~40 plaques from 3 matching sections per mouse.
(E) TUNEL assay (green) and NeuN staining (pink) in the hippocampal CA1 region.
(F) Quantification of volume of TUNEL+ stain found in NeuN+ nuclei from 2 corresponding brain sections per mouse.
(G and H) 4-month-old 5xFAD (n = 6) and 5xFAD SykΔMG (n = 8) mice were evaluated in the Morris water maze (MWM). Statistics for MWM acquisition were calculated on day 4. Combined data from 3 independent experiments.
(I) Performance in the elevated plus maze (EPM) was measured in 4-month-old 5xFAD and 5xFAD SykΔMG mice. Combined data from 2 independent experiments. Statistical significance between experimental groups was calculated by unpaired Student’s t test (B), (D), and (F)–(I). *p < 0.05, **p < 0.01, ***p < 0.001. Error bars represent mean ± SEM and each data point represents an individual mouse.
See also Figures S1 and S2.