Exploring Novel Immunodiagnostics for Prion Disease

Abstract

Prion Diseases, or Transmissible Spongiform Encephalopathies (TSEs), are rapidly progressive and fatal neurodegenerative diseases of mammals. TSEs of global importance include Creutzfeldt-Jakob Disease (CJD) in humans, Chronic Wasting Disease (CWD) in cervids, and Bovine Spongiform Encephalopathy (BSE) in cattle. These diseases occur when the normal cellular prion protein (PrPC) misfolds, producing the infectious isoform PrPSc,which can readily self propagate with no nucleic acid intermediate. PrPSc aggregates are insoluble self-molecules, which results in a large number of limitations pertaining to the prevention, detection, and treatment of TSEs; including a lack of accessible isoform-specific antibodies. Here, we describe a quantitative PCR method to explore prion protein epitope variability and availability by leveraging proximity ligation technology (PLA). We use a repertoire of nine known monoclonal anti-PrP antibodies to assess differences in prion protein conformations and establish “functional” and “non-functional” antibody probe pairs. In light of our results, we posit that exploring PrPSc strain diversity with available anti-PrP antibodies will lead to the development of ultrasensitive qPCR-PLA Protein Assays for precise detection and quantification of particular PrPSc strains.