The N-terminal sequence of prion protein consists an epitope specific to the abnormal isoform of prion protein (PrP(Sc))

PLoS One. 2013;8(2):e58013. doi: 10.1371/journal.pone.0058013. Epub 2013 Feb 28.

Abstract

The conformation of abnormal prion protein (PrP(Sc)) differs from that of cellular prion protein (PrP(C)), but the precise characteristics of PrP(Sc) remain to be elucidated. To clarify the properties of native PrP(Sc), we attempted to generate novel PrP(Sc)-specific monoclonal antibodies (mAbs) by immunizing PrP-deficient mice with intact PrP(Sc) purified from bovine spongiform encephalopathy (BSE)-affected mice. The generated mAbs 6A12 and 8D5 selectivity precipitated PrP(Sc) from the brains of prion-affected mice, sheep, and cattle, but did not precipitate PrP(C) from the brains of healthy animals. In histopathological analysis, mAbs 6A12 and 8D5 strongly reacted with prion-affected mouse brains but not with unaffected mouse brains without antigen retrieval. Epitope analysis revealed that mAbs 8D5 and 6A12 recognized the PrP subregions between amino acids 31-39 and 41-47, respectively. This indicates that a PrP(Sc)-specific epitope exists in the N-terminal region of PrP(Sc), and mAbs 6A12 and 8D5 are powerful tools with which to detect native and intact PrP(Sc). We found that the ratio of proteinase K (PK)-sensitive PrP(Sc) to PK-resistant PrP(Sc) was constant throughout the disease time course.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Monoclonal / immunology
  • Antibody Specificity
  • Cattle
  • Epitope Mapping*
  • Female
  • Immunization
  • Mice
  • Molecular Sequence Data
  • PrPSc Proteins / chemistry*
  • PrPSc Proteins / immunology*
  • PrPSc Proteins / metabolism
  • Prion Diseases / metabolism

Substances

  • Antibodies, Monoclonal
  • PrPSc Proteins

Grants and funding

This study was supported by a Grant-in-Aid from the BSE and Other Prion Disease Control Project of the Ministry of Agriculture, Forestry and Fisheries of Japan, and in part by grants for BSE research from the Ministry of Health, Labour and Welfare of Japan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.