Figure 2.

Human tauopathy lysates seeding endogenous mouse tau in primary non-Tg neurons. A, Left, Top, Representative images from immunocytochemistry (ICC) studies for anti-mouse tau-specific MAb T49 (green) on primary non-Tg hippocampal neurons treated with two different amounts of pathological tau from AD, CBD, and PSP cases (note: the PSP case is Case 1 only). Left, Bottom, Images from ICC for T49 (green) and MAP2 (red) overlay from AD-tau, CBD-tau and PSP-tau-treated neurons. Scale bar, 100 μm. B, Quantification of percentage area occupied by T49 signal/DAPI signal from ICC of neurons treated with AD-tau from three cases of AD (2 replicates), CBD-tau from three cases of CBD (2 replicates), and PSP-tau from one case of PSP (Case 1; 2 replicates) at different tau concentrations. One-way ANOVA with Tukey post hoc test comparing all groups was performed (Mean ± SEM plotted; F = 86.49, df = 24; *p < 0.05, **p < 0.01, **p < 0.001). C, Western blot for T49 on Sarkosyl-soluble supernatants (sup) and Sarkosyl-insoluble pellets (pel) extracted from neurons treated with AD-tau, CBD-tau, or PSP-tau. Western blot for GAPDH as loading control. D, Representative images from ICC for T49 (green) on primary non-Tg hippocampal neurons treated with PSP-tau from five different PSP cases. PSP Cases 1, 3, 4, and 5 were used to treat neurons with 15 ng of Sarkosyl pellet from the lentiform nuclei, and PSP Case 2 was used to treat neurons with 150 ng of final supernatant from frontal cortex. Scale bar, 100 μm. E, Top, Images are shown here of ICC for T49 from primary non-Tg hippocampal neurons treated with 200 ng of PSP-tau, or Tau5-immunodepleted PSP-tau from Case 1, or mock IgG-treated PSP-tau from Case 1. Bottom, Representative images are shown here of ICC for T49 from primary non-Tg hippocampal neurons treated with 100 ng of CBD-tau from n = 3 cases, or 17025-immunodepleted CBD-tau, or mock IgG-treated CBD-tau. Scale bar, 100 μm.