Ablation of cellular prion protein does not ameliorate abnormal neural network activity or cognitive dysfunction in the J20 line of human amyloid precursor protein transgenic mice.

Previous studies suggested that the cellular prion protein (PrP(c)) plays a critical role in the pathogenesis of Alzheimer's disease (AD). Specifically, amyloid-β (Aβ) oligomers were proposed to cause synaptic and cognitive dysfunction by binding to PrP(c). To test this hypothesis, we crossed human amyloid precursor protein (hAPP) transgenic mice from line J20 onto a PrP(c)-deficient background. Ablation of PrP(c) did not prevent the premature mortality and abnormal neural network activity typically seen in hAPPJ20 mice. Furthermore, hAPPJ20 mice with or without PrP(c) expression showed comparably robust abnormalities in learning and memory and in other behavioral domains at 6-8 months of age. Notably, these abnormalities are not refractory to therapeutic manipulations in general: they can be effectively prevented by interventions that prevent Aβ-dependent neuronal dysfunction also in other lines of hAPP transgenic mice. Thus, at least in this model, PrP(c) is not an important mediator of Aβ-induced neurological impairments.