Received on February 23, 2005
Accepted on June 2, 2005

Molecular Diagnostics and Genetics

Immunoquantitative PCR for Prion Protein Detection in Sporadic Creutzfeldt-Jakob Disease

¹ Centre de Recherche sur les Protéines Prions (CRPP) - Service d'Histologie Humaine, Université de Liège-CHU, Liège, Belgium
² Laboratoire de Neuropathologie, Centre Hospitalier Universitaire de Liège, Liège, Belgium
³ Roboscreen GmbH, Leipzig, Germany

^* To whom correspondence should be addressed. E-mail: willy.zorzi{at}ulg.ac.be.

Background: The most common human prion disorder is Creutzfeldt-Jakob disease (CJD); it includes sporadic, familial, iatrogenic, and variant subtypes. Diagnostic tests aim at detection with the highest specificity of very small deposits of abnormal prion protein (PrP).

Methods: We used immunoquantitative PCR (iqPCR) to detect proteinase K-resistant PrP (PrP^Res) in tissue from the middle frontal gyrus of 7 patients with sporadic CJD and 7 non-CJD cases. We compared iqPCR with routine optimized ELISA, Western blotting, and immunohistochemical analyses.

Results: The 4 methods showed similar 100% sensitivity and specificity for the diagnosis of CJD. Along with high specificity, however, iqPCR had a threshold for PrPRes detection at least 10-fold lower than that of the classic ELISA.

Conclusions: iqPCR is a new method for PrP^Res detection that combines 100% specificity with a detection threshold at least 10-fold lower than classic techniques. This method may improve the detection of minute PrP^Res deposits in tissues and body fluids and thus be useful for diagnostic and sterilization applications.