Abstract: The invention provides a rapid, sensitive immunoassay capable of detecting and quantitating pathogenic protein to a level of 3 to 5 logs. The preferred immunoassay utilized is a chemiluminescent endpoint for a Western blot immunoassay. The invention has been successfully applied to track the clearance of pathogenic protein during production of proteins derived from plasma. It is particularly applicable and has been confirmed by bioassay to relate TSE infectivity to quantitative results on prion protein.

Abstract: The invention provides a rapid, sensitive immunoassay capable of detecting and quantitating pathogenic protein to a level of 3 to 5 logs. The preferred immunoassay utilized is a chemiluminescent endpoint for a Western blot immunoassay. The invention has been successfully applied to track the clearance of pathogenic protein during production of proteins derived from plasma. It is particularly applicable and has been confirmed by bioassay to relate TSE infectivity to quantitative results on prion protein.

Abstract: Transmissible spongiform encephalopathies (TSEs) are a class of fatal, neurodegenerative diseases found in many mammalian species. Human TSEs include kuru, Creutzfeldt-Jakob disease (CJD), and fatal familial insomnia. Non-human TSEs include sheep scrapie, bovine spongiform encephalopathy (BSE), feline spongiform encephalopathy, and chronic wasting diseases in elk and mule deer. These neurodegenerative diseases are caused by prions and display characteristic amyloid plaque deposition. The only known component of the infectious prion is an abnormal, disease-causing isoform of the prion protein (PrP), called PrP scrapie (PrPSc). During a post-translational process, PrPSc is formed from the normal, cellular PrP isoform (PrPC). The scrapie isoform is less soluble, more proteinase-resistant, and more susceptible to aggregation than the wildtype protein.

Abstract: Disclosed is a method for separating prions from biological materials. The method includes adding a polyalkylene glycol, such as polyethylene glycol, to a solution of the biological material such that a precipitate containing the prion is formed. This precipitate is then separated from the solution of biological material, thereby removing prions. Biological materials include biologically derived fluids, such as cerebrospinal fluid, biological samples, such as brain homogenates, blood plasma fractions, and aqueous solutions of recombinantly produced products. The disclosed method provides an effective process for the removal of these infectious materials from the biological materials, which may be further processed to provide the therapeutic compositions.