PSEN2 and Alzheimer disease: Since 3 × Tg-AD mice display learning and memory deficits starting at 6.5 months of age (Stover et al., 2015), develop amyloid plaques starting at about 9 months of age and NFTs starting about 12 months of age (Oddo et al., 2003), we started to immunize the 9-10-month-old 3xTg-AD mice and age-matched WT mice for 5 immunizations with a 3-week interval to test the therapeutic activity of SNAP-AD5.