Fig 1: Human BIN1 isoform 9 favors the release of Tau via EVs in vitro as well as increasing the area of pTau staining in vivo. (A) Western blot of Tau and BIN1 in cell lysates (left panel) and EVs (right panel) from HEK293T cells transfected with Tau 2N4R alone or in presence of BIN1 isoform 1 or 9 (indicated by arrows). GAPDH (left panel) represents a cell lysate loading control. CLATHRIN (right panel) serves as an extracellular vesicle loading control. One representative experiment shown out of 4 independent replicates. WB images shown represent cropped sections of full blots shown in Supplementary Fig. 12. (B) Western blot of Tau and BIN1 in cell lysates (left panel) and EVs (right panel) from HEK293T cells transfected with Tau 2N4R P301L-YFP alone or in presence of BIN1 isoform 1 or 9 (indicated by arrows). GAPDH (left panel): cell lysate loading control. CLATHRIN (right panel): extracellular vesicle loading control. One representative experiment shown out of 4 independent replicates. WB images shown represent cropped sections of full blots shown in Supplementary Fig. 12. (C) Experimental scheme. Artwork by Channa Bao. (D) Representative image of Immunohistochemical staining of pTau (40E8) in hippocampi of PS19 mice injected with AAV expressing GFP or GFP-P2A-hBIN1 isoform 9. Scale: 600 µm. (E) Plot representing the percentage of pTau staining area in the ipsilateral hippocampus (area of pTau staining normalized to the size of the ipsilateral hippocampus for each animal). Each triangle represents one animal. Unpaired parametric Student’s t-test two tailed, 95% confidence: p-value: *p < 0.05; **<0.01; ***p < 0.001.