Detection and typing of abnormal disease-associated prion protein (PrPSc) isoforms by partial proteolytic degradation and Western blot analysis.
Western blot analysis of protease resistant prion protein (PrPres) in post-mortem brain tissue homogenates of cerebral cortex samples from the two most common subtypes of sporadic Creutzfeldt-Jakob disease (sCJD MM1 and sCJD VV2), compared with that of variant Creutzfeldt-Jakob disease (vCJD), and similar analysis of brain stem from a case of bovine spongiform encephalopathy (BSE).
In each example three bands are present, representing non-glycosylated (o), mono-glycosylated (*) and di-glycosylated (**) PrPres. PrPres type 1 differs from type 2 in terms of electrophoretic mobility, most obviously seen by comparing the mobility of the non-glycosylated band. The type 2 PrPres characteristic of vCJD (type 2B) has a predominant diglycosylated band (**), distinguishing it from the type 2 PrPres found in sCJD (type 2A). The predominance of the di-glycosylated band is a feature shared by vCJD and BSE.
The monoclonal antibody 3F4 (which can be obtained from Dako or Signet) is CE marked and was used for the detection and typing of the human specimens shown here. Bovine PrP is not recognised by 3F4, and the vCJD and BSE comparison shown employed the monoclonal antibody 6H4 (from Prionics).
The PrP typing nomenclature is that of Parchi & Gambetti. (Parchi et al., Typing prion isoforms. Nature 1997;386:232-234). The cases of CJD originate from the UK and the Western blot image was provided by Dr. Mark Head (National CJD Surveillance Unit). The BSE tissue was supplied by the Veterinary Laboratory Agency’s TSE Archive (UK) and the Western blot image was provided by Ms Zuzana Krejciova (National CJD Surveillance Unit).
For more information please contact Mark Head firstname.lastname@example.org