Validation of 14-3-3 Protein as a Marker in Sporadic Creutzfeldt-Jakob Disease Diagnostic

Mol Neurobiol. 2016 May;53(4):2189-99. doi: 10.1007/s12035-015-9167-5. Epub 2015 May 7.


At present, the testing of 14-3-3 protein in cerebrospinal fluid (CSF) is a standard biomarker test in suspected sporadic Creutzfeldt-Jakob disease (sCJD) diagnosis. Increasing 14-3-3 test referrals in CJD reference laboratories in the last years have led to an urgent need to improve established 14-3-3 test methods. The main result of our study was the validation of a commercially available 14-3-3 ELISA next to the commonly used Western blot method as a high-throughput screening test. Hereby, 14-3-3 protein expression was quantitatively analyzed in CSF of 231 sCJD and 2035 control patients. We obtained excellent sensitivity/specificity values of 88 and 96% that are comparable to the established Western blot method. Since standard protocols and preanalytical sample handling have become more important in routine diagnostic, we investigated in a further step the reproducibility and stability of 14-3-3 as a biomarker for human prion diseases. Ring trial data from 2009 to 2013 revealed an increase of Fleiss' kappa from 0.51 to 0.68 indicating an improving reliability of 14-3-3 protein detection. The stability of 14-3-3 protein under short-term and long-term storage conditions at various temperatures and after repeated freezing/thawing cycles was confirmed. Contamination of CSF samples with blood appears likely to be an important factor at a concentration of more than 2500 erythrocytes/μL. Hemolysis of erythrocytes with significant release of 14-3-3 protein started after 2 days at room temperature. We first define clear standards for the sample handling, short- and long-term storage of CSF samples as well as the handling of blood- contaminated samples which may result in artificially elevated CSF levels of 14-3-3.

Keywords: 14-3-3 protein; Biomarker; Cerebrospinal fluid; Creutzfeldt-Jakob disease; Pre-mortem test; Standardization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 14-3-3 Proteins / cerebrospinal fluid
  • 14-3-3 Proteins / metabolism*
  • Biomarkers / metabolism
  • Blotting, Western
  • Creutzfeldt-Jakob Syndrome / cerebrospinal fluid
  • Creutzfeldt-Jakob Syndrome / diagnosis*
  • Creutzfeldt-Jakob Syndrome / metabolism*
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Laboratories
  • Preservation, Biological
  • Protein Isoforms / metabolism
  • Reference Standards
  • Reproducibility of Results
  • S100 Proteins / metabolism
  • Sensitivity and Specificity
  • tau Proteins / metabolism


  • 14-3-3 Proteins
  • Biomarkers
  • Protein Isoforms
  • S100 Proteins
  • tau Proteins

Supplementary concepts

  • Creutzfeldt-Jakob Disease, Sporadic