Disease-associated prion protein is not detectable in human systemic amyloid deposits

G A Tennent1, M W Head, M Bishop

  • 1Centre for Amyloidosis and Acute Phase Proteins (incorporating the UK NHS National Amyloidosis Centre), Department of Medicine, University College London, London NW3 2PF, UK. g.tennent@medsch.ucl.ac.uk

The Journal of Pathology
|October 24, 2007
PubMed

Insights

This study investigated the link between prion diseases and human systemic amyloidosis. Researchers found no evidence of prion protein (PrPSc) in human amyloid tissues, ruling out a connection.

Area of Science:

  • Neurology
  • Pathology
  • Biochemistry

Background:

  • Transgenic mice studies suggested a link between prion protein (PrP) and systemic amyloidosis.
  • The prion protein conformation associated with transmissible spongiform encephalopathy (TSE) is PrPSc.
  • Previous research lacked characterization of amyloid fibril protein in murine models and human associations.

Purpose of the Study:

  • To investigate the presence of PrPSc in human systemic amyloidosis tissues.
  • To determine if amyloid fibrils in human systemic amyloidosis contain protease-resistant prion protein (PrPres).
  • To analyze the prion protein gene (PRNP) in patients with systemic amyloidosis.

Main Methods:

  • Immunohistochemistry was used to detect PrPSc in human amyloidotic tissues.
  • Western blotting was employed to detect PrPres in isolated amyloid fibrils.
  • Complete PRNP gene sequencing was performed on patients with amyloidosis.

Main Results:

  • No specific immunohistochemical staining for PrPSc was observed in cardiac and visceral tissues from patients with systemic amyloidosis.
  • Protease-resistant prion protein (PrPres) was undetectable in amyloid fibrils from systemic amyloid deposits.
  • Analysis revealed only the wild-type PRNP gene sequence, including common polymorphisms, in amyloidosis patients.

Conclusions:

  • The study found no evidence supporting a relationship between prions or TSE and human systemic amyloidosis.
  • These findings do not support the hypothesis that PrPSc is involved in the pathogenesis of human systemic amyloidosis.
  • The research provides reassurance against a prion-related etiology for human systemic amyloid deposition.

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