title: Highly sensitive, quantitative cell-based assay for prions adsorbed to solid surfaces.
abstract: Prions are comprised principally of aggregates of a misfolded host protein and cause fatal transmissible neurodegenerative disorders of humans and animals, such as variant Creutzfeldt-Jakob disease and bovine spongiform encephalopathy. Prions pose significant public health concerns, including contamination of blood products and surgical instruments; require laborious and often insensitive animal bioassay to detect; and resist conventional hospital sterilization methods. A major experimental advance was the cell culture-based scrapie cell assay, allowing prion titres to be estimated more precisely and an order of magnitude faster than by animal bioassays. Here we describe a bioassay method that exploits the marked binding affinity of prions to steel surfaces. Using steel wires as a concentrating and sensitization tool and combining with an adapted scrapie cell endpoint assay we can achieve, for mouse prions, a sensitivity 100x higher than that achieved in standard mouse bioassays. The rapidity and sensitivity of this assay offers a major advance over small animal bioassay in many aspects of prion research. In addition, its specific application in assay of metal-bound prions allows evaluation of novel prion decontamination methods.
authors.affiliation: Medical Research Council Prion Unit, Department of Neurodegenerative Disease, University College London Institute of Neurology, Queen Square, London WC1N 3BG, United Kingdom.
authors.forename: Julie Ann
authors.initials: JA
authors.lastname: Edgeworth
authors.forename: Graham S
authors.initials: GS
authors.lastname: Jackson
authors.forename: Anthony R
authors.initials: AR
authors.lastname: Clarke
authors.forename: Charles
authors.initials: C
authors.lastname: Weissmann
authors.forename: John
authors.initials: J
authors.lastname: Collinge
mesh_terms: D002460:Cell Line; D011328:Prions / Q000032:analysis* / Q000378:metabolism*; D055550:Protein Stability; D013379:Substrate Specificity; D013696:Temperature
chemical_list: D011328:Prions