PHF1 and Alzheimer disease: We found an increase of total tau but a decrease in tau hyperphosphorylation (p-tau normalized with total tau) at Thr231 and 12E8 (Ser262/Ser356) sites, as well as a trend at PHF1 (Ser396/Ser404, p = 0.098) sites in the forebrain of 43D-immunized 3×Tg-AD mice (Fig. 7a and b).