In this study, we explored the potentially beneficial immunotherapeutic power of the 12A12mAb by means of its intravenous (i.v.)administration in two lines of Alzheimer’s disease Tg animals with different genetic backgrounds, such as Tg2576 carrying the APP KM670/671NL Swedish mutation and 3xTg mice expressing the amyloid precursor protein KM670/671NL Swedish mutation, tauP301L, PS1M146V human transgenes. Here, APP is linked to Alzheimer disease.