Unlike other models of AD (e.g., the APP/PS1), intracellular Aβ accumulation should be the earliest (starting at 6 months) and preponderant pathological manifestation in 3xTgAD mice, while later on (e.g., at 15 months) both hippocampal and coronal tissues should start presenting evident extra-cellular Aβ plaques and tau pathology. Here, APP is linked to Alzheimer disease.