PSEN1 and memory impairment: Because the memory impairments in EOAD are caused by accumulation of Aβ plaques and hippocampal microgliosis31, we conducted an immunofluorescent analysis for Aβ plaques (using the 6E10 Ab) and ionized calcium binding adaptor 1 (Iba, a microglial cell marker) in cryopreserved brain sections of APP/PS1-BKO (30 weeks old), 3×TgAD-BKO (60–70 weeks old) and age- and sex-matched control mice.