Packaging of prions into exosomes is associated with a novel pathway of PrP processing

Abstract

Prion diseases are fatal, transmissible neurodegenerative disorders associated with conversion of the host-encoded prion protein (PrPC) into an abnormal pathogenic isoform (PrPSc). Following exposure to the infectious agent (PrPSc) in acquired disease, infection is propagated in lymphoid tissues prior to neuroinvasion and spread within the central nervous system. The mechanism of prion dissemination is perplexing due to the lack of plausible PrPSc-containing mobile cells that could account for prion spread between infected and uninfected tissues. Evidence exists to demonstrate that the culture media of prion-infected neuronal cells contain PrPSc and infectivity but the nature of the infectiv..