Fig. 1

Tau and Aβ pathologies in the 5xFAD/AAV-tau mouse model. a Representative image of the distribution of Aβ (4G8, in green) and human tau (HT7, in red) in the hippocampal formation of 5xFAD/AAV-tau mice. b, c Higher magnification image in the ipsilateral (b) and contralateral CA3 (c). d Percentage of the total hippocampal area covered by HT7 staining in the ipsi- and contralateral hippocampus, in WT/AAV-tau and 5xFAD/AAV-tau mice. e Representative image of the distribution of Aβ (4G8, in green) and Ser202/Thr205 phospho-tau immunoreactivity (AT8, in red) in the hippocampus of 5xFAD/AAV-tau mice. f, g Higher magnification image in the ipsilateral (f) and contralateral CA3 (g). Note that in the ipsilateral hippocampus, AT8-positive tau is mainly located in the soma and neurites of neuronal cells. In the contralateral hippocampus, AT8-positive tau puncta (arrowheads) are mainly located near amyloid plaques (4G8, in green). h Percentage of the hippocampal surface covered by AT8 phospho-tau immunoreactivity in the ipsilateral hippocampus, comparing WT/AAV-tau and 5xFAD/AAV-tau mice. i Percentage of the surface covered by AT8 phospho-tau immunoreactivity in the contralateral hippocampus. Note the significant coverage increase in the 5xFAD/AAV-tau mice, which reflects the presence of phospho-tau-positive neuritic puncta. Scale bars: 800 µm (a, e) and 100 µm (b, c, f, g). Statistical analysis: unpaired two-tailed Student’s t-test, ****p < 0.0001; WT/AAV-tau: n = 13 mice, 5xFAD/AAV-tau: n = 15 mice