Effect of 3-APS on Tau transfected cell line. HEK 293 expressing Tau cells were treated with 100 μM and 500 μM of 3-APS and stained using an antibody against human Tau (ab T14) (A) or with 0.01 % thioflavin S (Th-S) (B). Quantitation of both T14 (C) and Thioflavin S (D) fluorescence observed by fluorescence microscopy is shown. The fluorescence intensity of each sample was obtained by background subtraction. A significant fluorescence intesity increase (P < 0.05 as compared with untreated cells) is shown for both T14 and Thioflavin S staining. The average of at least three separate determinations is indicated. DAPI was used for nuclei staining.