Extracellular Vesicles Derived from Postmortem Human Brain Tissue Contain Seed-competent C-terminal Tau Fragments, and Provide Proteomic Clues to the Identity of Selectively Vulnerable Cell Populations in Human Tauopathies: Molecular and Cell Biology: Tau-related Mechanisms

Abstract

Background: Pathological tau is spread along anatomically connected networks, originating in areas containing particularly vulnerable cell populations. It is hypothesized that tau is released and spread as free tau, or via extracellular vesicles (EVs) that include exosomes (30-150 nm), microvesicles (100-1000 nm), and apoptotic bodies (1000-5000 nM). While a variety of different EV tau species have been identified in tissue, cells, and bio-fluids, EV tau has not yet been described from human post-mortem tauopathy brain tissue.