Fig. 4

Microglial activation is reduced in mice with a decrease in astrocytic apoE. A Microglia staining in the cortex and hippocampus of female Cre- and Cre + mice. Representative images are of female brain sections immunostained using an anti-Iba1 antibody (red). Scale bars = 200 μm. B Microglial coverage in the cortex of Cre- and Cre + mice. Percent of cortex area covered by microglia was determined by analyzing Iba1 stained brain sections (n = 10–19). C ApoE+ microglia around fibrillar amyloid plaques in female Cre- and Cre + mice. Representative images are of apoE immunostaining (green) using an anti-apoE antibody and microglia immunostaining using an anti-Iba1 antibody (magenta) around X-34 stained (blue) amyloid plaques. ApoE co-localized with Iba1 appears white. Scale bars = 20 μm. D Microglial apoE levels around fibrillar amyloid plaques in Cre- and Cre + mice. Area of apoE+ microglia per total microglia area was determined by analyzing the level of apoE+ microglia staining to total microglia staining within 10 μm of X-34 stained plaques (n = 5–12). E Microglia clustering and activated microglia around fibrillar amyloid plaques in female Cre- and Cre + mice. Representative images are of Clec7a immunostaining (green), using an anti-Clec7a antibody, and microglia immunostaining using an anti-Iba1 antibody (magenta) around X-34 stained (blue) amyloid plaques. Clec7a co-localized with Iba1 appears white. Scale bars = 20 μm. F Clustering of microglia around fibrillar amyloid plaques in Cre- or Cre + mice. Area covered by microglia around fibrillar amyloid plaques was determined by analyzing the level of Iba1 staining within 15 μm of X-34 stained plaques (n = 6–14). G Coverage of activated microglia around fibrillar amyloid plaques in Cre- or Cre + mice. Area of activated microglia around fibrillar amyloid plaques was determined by analyzing the level of cleca7a staining within 15 μm of X-34 stained plaques per total area of Iba1 (n = 6–14). A-G * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001; three-way ANOVA and uncorrected Fisher’s LSD test in (B), (D), (F), and (G). Data are expressed as mean ± SEM. See Supplementary Table 1 for detailed statistics