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Updated: Apr 23, 2026
10:12
Protein Misfolding Cyclic Amplification of Prions
Published on: November 7, 2012
18.8K
Prion strains are differentially released through the exosomal pathway
Zaira E Arellano-Anaya1, Alvina Huor, Pascal Leblanc
1INRA, UMR 1225, IHAP, 31076, Toulouse, France.
Cellular and Molecular Life Sciences : CMLS
|September 18, 2014
Summary
Prion infection spreads through cell-to-cell transfer. This study reveals that exosomes actively secrete prions, with the amount secreted significantly varying by prion strain.
Area of Science:
- Neuroscience
- Cell Biology
- Infectious Diseases
Background:
- Prion diseases involve the cell-to-cell transmission of infectious proteins.
- Potential transmission routes include direct cell contact and extracellular vesicles.
- The specific pathways and their strain-dependent variations remain unclear.
Purpose of the Study:
- To investigate the mechanisms of prion cell-to-cell transfer.
- To determine the role of the exosomal pathway in prion secretion.
- To analyze how different prion strains influence secretion levels.
Main Methods:
- Utilized RK13 cells infected with three distinct prion strains.
- Quantified extracellular prion infectivity.
- Analyzed prion secretion via the exosomal pathway.
Main Results:
- Exosomal pathway is the primary route for extracellular prion release.
- The quantity of secreted prions is highly dependent on the prion strain.
- Infectious exosomes from cultured cells are suitable for prion spiking experiments.
Conclusions:
- Cell-to-cell prion transfer is significantly mediated by active exosome secretion.
- Prion strain dictates the efficiency of exosomal secretion.
- Differential interactions between prion strains and cellular machinery may govern secretion.
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