Fig. 6

Microglial CD2AP haploinsufficiency reverses synapse loss in 5xFAD mice. A Representative images of Golgi staining of the hippocampal CA1 neuronal spines from 7-month-old mice. Scale bar: 10 μm. Spine numbers were quantified for comparison. n = 5 mice per genotype. An average of data from approximately 8 neurites in each mouse was indicated. 1-way ANOVA followed by Tukey’s post hoc test. B Representative images of the hippocampus of 7-month-old mice immunostained with antibodies against synapsin 1 (SYN1, in magenta) and Aβ (6E10, in green). Scale bar: 5 μm. The percentages of SYN1 area were quantified for comparison. n = 3 or 4 mice per genotype. An average of data from 4 plaques in each mouse was indicated. Unpaired Student’s t test. C Representative images of the hippocampus of 7-month-old mice immunostained with the 6E10 antibody (in magenta) and an anti-LAMP1 antibody (in green) and stained with DAPI (in blue). Scale bars for regular and zoom images are 100 μm and 20 μm, respectively. Aβ plaque–associated LAMP1-positive dystrophic neurites were quantified for comparison. n = 4 or 5 mice per genotype. An average of data from approximately 6 cells in each mouse was indicated. Unpaired Student’s t test. D Representative images and 3D surface and filament rendering of Iba1⁺ microglia (in green) containing PSD95⁺ puncta (in red) and the nuclei (in blue) in the hippocampus of 7-month-old mice with different genotypes. Each 2D image is generated from superimposing a series of 15 pictures with 1 μm step size in a z-stack direction to maximally reveal microglial branches. White arrows indicate PSD95⁺ puncta in microglia. Scale bars for regular, zoom in, 3D surface, and filament rendering images are 20 μm, 5 μm, 4 μm, and 10 μm, respectively. The percentages of PSD95⁺ puncta volume entirely within the microglia volume but outside the nucleus region, and total processes and branch numbers of microglia were quantified for comparison. n = 4 or 5 mice per genotype. An average of data from approximately 12 cells in each replicate was indicated. 1-way ANOVA followed by Tukey’s post hoc test. Data are presented as mean ± SEM. *P < 0.05; **P < 0.01; ns, not significant