Development of an Automated Capillary Immunoassay to Detect Prion Glycotypes in Creutzfeldt-Jakob Disease

Lab Invest. 2023 Mar;103(3):100029. doi: 10.1016/j.labinv.2022.100029. Epub 2023 Jan 10.

Abstract

Creutzfeldt-Jakob disease (CJD) comprises a group of transmissible neurodegenerative diseases with vast phenotypic diversity. Sporadic CJD heterogeneity is predominantly influenced by the genotype at codon 129 of the prion-encoding gene and the molecular weight of PrPSc fragments after protease digestion, resulting in a classification of 6 subtypes of CJD (MM1, MM2, MV1, MV2, VV1, and VV2). The majority of cases with CJD can be distinguished using this classification system. However, a number of reported CJD cases are phenotypically unique from others within their same subtype, such as variably protease-sensitive prionopathies, or exist as a mixture of subtypes within the same patient. Western blotting of brain tissue, along with the genotyping of codon 129 of the prion-encoding gene, is considered the "gold standard" for the biochemical characterization of CJD. Western blotting requires a significant amount of prion protein for detection, is labor-intensive, and is also associated with high interassay variability. In addition to these limitations, a growing body of research suggests that unique subtypes of CJD are often undetected or misdiagnosed using standard diagnostic western blotting protocols. Consequently, we successfully optimized and developed a capillary-based western assay using the JESS Simple Western (ProteinSimple) to detect and characterize prion proteins from patients with CJD. We found that this novel assay consistently differentiated CJD type 1 and type 2 cases with a limit of detection 10 to 100× higher than traditional western blotting. Cases with CJD in which type 1 and type 2 coexist within the same brain region can be detected using type 1-specific and type 2-specific antibodies, and we found that there was remarkable specificity for the detection of cases with variably protease-sensitive prionopathy. The assay presented displays outstanding sensitivity, allowing for the preservation of valuable samples and enhancing current detection methods.

Keywords: Creutzfeldt-Jakob disease; Prion; capillary electrophoresis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Brain / metabolism
  • Codon / metabolism
  • Creutzfeldt-Jakob Syndrome* / diagnosis
  • Creutzfeldt-Jakob Syndrome* / metabolism
  • Humans
  • Peptide Hydrolases / metabolism
  • Prion Proteins / genetics
  • Prion Proteins / metabolism
  • Prions* / metabolism

Substances

  • Prions
  • Prion Proteins
  • Peptide Hydrolases
  • Codon