MAPT and Alzheimer disease: To develop a highly successful immunotherapy for AD patients, several problems need to be overcome including: avoiding excessive cell-mediated immunity, which has been linked to autoimmune encephalitis; reducing CAA deposition without inducing associated microhemorrhages and/or vasogenic edema; reducing tau-related pathology, which is known to correlate with clinical status better than amyloid deposits, and targeting of oligomeric species, which are the most toxic [3].