MAPT and Alzheimer disease: PAD-exposed tau inclusions (TNT1 antibody) were highly colocalized with AT8 phosphorylated tau (AT8 antibody; Fig. 4A–D; fraction of TNT1 overlapping with AT8 = 0.688 ±0.016) and tau phosphorylated at Ser422 (pS422 antibody; Fig. 4E-H; fraction of TNT1 overlapping with pS422 = 0.889 ±0.022) in AD-tau neurons.