APP and Alzheimer disease: Similar effects of anti-tau immunization on Aβ have been observed in 3 × Tg-AD mice, in which the N-terminal-targeting tau antibody 43D reduced amyloid precursor protein (APP) levels in the hippocampus (CA1) and amyloid plaques in the subiculum, with a trend of decrease for Aβ40 and Aβ42 levels in the forebrain.