The diagnostics of prion diseases, including Creutzfeldt-Jakob disease (CJD), is still challenging as none of currently available tests, including magnetic resonance imaging, electroencephalogram and detection of 14-3-3 protein in cerebrospinal fluid, are sufficient for definite premortem diagnosis. This paper presents sensitive methods based on the ability of PrPSc protein to induce the PrPc to PrPSc conversion in vitro which have been developed within the last few years in order to detect trace amounts of the abnormal prion protein in cerebrospinal fluid or blood. Among those methods, the quaking-induced conversion (QuIC) with the use of purified recombined PrPc protein as a substrate seems to be the most promising. We discuss the current research in optimization of the method as well as the perspectives of its possible applications in diagnostics and scientific investigations.

Creutzfeldt-Jakob disease, diagnostic markers, prion protein amplification, protein misfolding cyclic amplification (PMCA), quaking-induced conversion (QuIC)