Prospects For a Preclinical Diagnostic Test

Abstract

At present diagnosis of BSE in cattle and sheep scrapie routinely requires post-mortem confirmation which is traditionally performed by neurohistological examination for Spongiform Vacuolation. Detection of disease specific forms of the host protein PrP, called PrP^Sc, offers alternatives. Deposits can be detected immunohistochemically, by searching tissue extracts by electron microscopy for the fibrils (scrapie associated fibrils: SAF) which are comprised of PrP^Sc, or immunoblotting of tissue extracts for PrP^Sc. In this paper we examine the possibilities of using the immunochemical detection of PrP^Sc diagnostically. We have raised antibody reagents to PrP, used them to determine the kinetics of PrP^Sc deposition in murine models of the disease and to determine if PrP^Sc can be detected in ruminant tissues from BSE or scrapie infected animals.