APP and Alzheimer disease: Oocytes microtransplanted with membranes from AD donors had a more depolarized resting membrane potential than those injected with membranes from MCI donors and a similar trend versus those injected with control membranes, possibly due to oligomeric Aβ pore-forming properties present in P2 fractions [10, 78] (Fig. 1b, g); indeed, the larger the abundance of the Aβ precursor protein (APP) measured in proteomics, the more positive the resting membrane potential of transplanted oocytes (R2 = 0.34; p = 0.023).