Prion detection in peripheral tissues

A firm diagnosis of variant Creutzfeldt Jakob disease (vCJD) is difficult to make because it is based on distinguishing misfolded prion proteins (PrP^Sc) from normally folded prion proteins in human brain biopsies. In 20 July issue of the Lancet, Wadsworth and colleagues from Imperial College School of Medicine, London, UK, describe a new technique based on a highly sensitive immunoblotting assay that can accurately detect PrP^Sc in peripheral tissue in patients suspected of vCJD.

Wadsworth et al. applied a selective precipitation technique combined with high-sensitivity western blotting and enhanced chemiluminescence to identify PrPSc in post-mortem tissues from four patients with confirmed vCJD and from individuals without neurological disease. With this method they could detect PrPSc in peripheral tissue at concentrations 104-105-fold lower than those reported in the brain. Concentrations of PrPSc were consistently higher in tonsils and spleen while all other tissues tested (including appendix and blood) were negative, except ...