Neuropathological and molecular comparison between clinical and asymptomatic bovine spongiform encephalopathy cases

Acta Neuropathol. 2007 Nov;114(5):501-8. doi: 10.1007/s00401-007-0283-9. Epub 2007 Sep 1.

Abstract

Interest in the proper neuropathological and molecular characterization of bovine spongiform encephalopathy (BSE) has increased since asymptomatic and atypical cases were detected in the cattle population by active disease surveillance. In this respect we investigated a total of 95 confirmed BSE cases originating from different active and passive surveillance categories (clinical suspects, emergency-slaughter, fallen stock and routinely slaughter) in Switzerland for their neuropathological and molecular phenotype. We looked for measurable differences between these categories in lesion profile, severity of spongiform change, degree of astrocytosis as well as immunohistochemical and molecular patterns of the disease-associated isoform of the prion protein (PrPd) in the caudal brainstem. Our results indicate significantly higher intensities of spongiform change in clinically affected compared to asymptomatic BSE cases. Similar effects were in trend observed for the intensities of PrPd deposition and astrocytosis, whereas the frequencies of morphological PrPd types and the molecular patterns in Western immunoblot were not different. Importantly, none of the animals included in this study revealed features of atypical BSE. Taken together, this study suggests that both clinically affected as well as asymptomatic Swiss BSE cases in cattle share the neuropathological and molecular phenotype of classical BSE and that asymptomatic classical BSE cases are at a pre-clinical stage of the disease rather than representing a true sub-clinical form of BSE.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / metabolism
  • Astrocytes / pathology
  • Biomarkers / analysis
  • Biomarkers / metabolism
  • Brain / metabolism
  • Brain / pathology*
  • Brain / physiopathology*
  • Cattle
  • Disease Notification
  • Disease Progression
  • Encephalopathy, Bovine Spongiform / metabolism
  • Encephalopathy, Bovine Spongiform / pathology*
  • Encephalopathy, Bovine Spongiform / physiopathology*
  • Gliosis / metabolism
  • Gliosis / pathology
  • Gliosis / physiopathology
  • Phenotype
  • Prions / genetics
  • Prions / metabolism*
  • Protein Isoforms / genetics
  • Protein Isoforms / metabolism
  • Retrospective Studies
  • Switzerland

Substances

  • Biomarkers
  • Prions
  • Protein Isoforms