Development of an Assay for the Detection of PrPres in Blood and Urine Based on PMCA Assay an ELISA Methods

摘要

The focus of this program is the development of a pre-clinical blood- based TSE diagnostic. The assay is been developed with test material from two animal models: the hamster infected with the 263K strain of scrapie and the sheep either naturally or experimentally infected with scrapie. Using hamster plasma, we have developed an assay that can serve as the platform for a TSE blood-based test. The assay uses antibodies that cross-react with human PrP which should allow for a rapid conversion to a human TSE assay. The assay indicated high sensitivity and good reproducibility and was applied to measure PrP concentration in normal hamster plasma and in normal and infected hamster brains. In the prototype assay, infected hamster plasma will be digested with proteinase K, denatured to allow PrP(exp res) to be captured by our proprietary immuno-affinity resin, eluted from the resin and detected with the ORIGEN analyzer. The issues currently under investigation are the proteinase K digestion to reduce the normal PrP concentration to below the level of prpres estimated to be present in infected plasma and the denaturation of PrP(exp res) in plasma.