Fig. 2

Seeding activity increases with age and anticipates AT8 pathology in PS19 mice. a AT8 staining of phospho-tau pathology in the dentate gyrus (DG) and entorhinal cortex/amygdala (EC/A) of a 12 month old WT mouse, and in PS19 mice at 1, 3, 6, 9, and 12 months of age. AT8 staining increases with age in PS19 mice. See Additional file 2: Figure S2a for representative images of whole-brain slices from 12-month-old WT and PS19 mice. b AT8 tau pathology was quantified in the DG and EC/A of WT and PS19 mice. WT mice were collected from various ages. Six PS19 mice at each age were assessed for tau pathology. Threshold analysis was performed to quantify the percentage of area occupied by AT8 staining in the region of interest. DG AT8 pathology did not rise above baseline staining in 1 month mice until 5 months of age. EC/A AT8 pathology did not show significant increases until 7 months of age. See Additional file 2: Figure S2b for nonlinear regression model of time-course AT8 staining data, and Table 1 for details regarding mice used in this study. c. Seeding activity was assessed from adjacent free-floating brain slices of WT and PS19 mice. 1 mm punch biopsies from the DG and EC/A were homogenized and transduced into biosensor cells. Tau seeding activity increased above baseline by 2 months of age for both the DG and EC/A. See Additional file 2: Figure S2b for nonlinear regression model of tau seeding activity time course data, and Additional file 2: Figure S2c for a direct comparison of seeding activity versus AT8 tau pathology. Error bars = S.E.M; * = p < .05; ** = p < .01