Molecular diagnostic of CJD by detection of single prion
2010: 1 year / Grant: 50 000 euros
Project: This project aimed to create a diagnostic method for the detection of PrPTSE in blood. This method is named “surface FIDA” (fluorescence intensity distribution analysis) and is based on the capture and immobilization on a surface of PrPTSE aggregates, and revelation by an ultrasensitive lazer optical approach.
Main results and related published data: Following several adaptations of their initial method, the group has published a 4-step methodology on sheep blood plasma: -detergent and lipase treatment to separate PrP from blood lipophilic components, -precipitation of PrPTSE aggregates by phosphotungstic acid (PTA), -immobilization on a glass surface by covalently bound capture antibodies, -labelling with fluorescent antibody probes and lecture with a laserscanning microscopy. They have observed, not only a proportionality between the size of the PrPTSE aggregates and the signal intensity, but also the possibilityto differentiate scrapie infected sheep from uninfected sheep. This technique was also able to discriminate between BSE infected cows and non-infected cows on brain homogenates. As expected, no PrPTSE was detected in the blood of the BSE positive cows.