MAPT and Alzheimer disease: We next examined the efficiency of DEPTAC in reducing tau phosphorylation at multiple AD-related sites, including the Ser199, Thr205, Ser396, Ser404, and the AT8 (Ser199/Ser202/Thr205) epitopes,11 in primary cultured rat hippocampal neurons with lentivirus-mediated overexpression of human tau (hTau).