APP and Alzheimer disease: Subsequently, after the introduction of the APP transgenic mouse model, several groups performed the injection of Aβ-rich brain extracts from AD patients or aged APP transgenic mice into APP transgenic hosts [126,127,128,129,130,131,132,133,134,135,136] showing that it was possible to recapitulate Aβ deposition (i.e., Aβ plaques and cerebral Aβ angiopathy) even using sub-attomolar amounts of brain-derived Aβ [137].