MAPT and Alzheimer disease: Although an important difference from transmissible spongiform encephalopathies (TSEs) is that prions behave like infectious agents, prion-like diseases belong to a group of protein misfolding neurodegenerative diseases that are characterized by the abnormal aggregation of defined host proteins (e.g., Amyloid β (Aβ) and tau in Alzheimer’s disease, α-synuclein in Parkinson’s disease, mutant polyglutamine repeats in Huntington’s disease, and TDP-43 in ALS and FTLD).