Proteomic analysis of the entorhinal cortex and CA1 subfields of the hippocampus of macaques injected with tau seeds from Alzheimer’s brain

The "prion-like" features of Alzheimer’s disease (AD) tauopathy and its relationship with amyloid β (Aβ) has never been experimentally studied in primates phylogenetically close to humans. We injected 17 macaques in the entorhinal cortex with nanograms of tau proteopathic seeds purified from AD brains or control extracts from aged-matched healthy brains, with or without intracerebroventricular co-injections of recombinant Aβ oligomers. After neuropathological examination of the macaque’s brain, we also performed mass spectrometry-based proteomics of macaques’ entorhinal cortex and CA1 to study the spatial response (local and distant) to tau seeds injections (and its modulation by oligomeric Aβ).