PrPTSE detection

Prion Blood Primate

Assessment of prion infectivity in blood in primate and sheep models, and evaluation of removal processes

2007: 3 years / Grant: 206 000 euros

Project: The aims of the project were 1) to assessthe risk of prion blood contamination through the use of non human primates infected with vCJD or BSE, and 2) to evaluate the risk of prion content in blood samples and blood derivatives after treatments designed to reduce plasmatic protein levels applied in transfusion centers.

Results and related published data: The work of different collaborating laboratories was not finished at the time of the final report, as some primate prion infection steps required a couple of years to be completed. During this project, and due in part to the financial support of Alliance Biosecure, the use of the Tg650 HuPrP transgenic mice forvCJD transmission (from brain tissue first) was validated. The possibility to detect PrPTSE in the spleen long before its detection in the brain was also described, and was shown to be as sensitive as animal survival time bioassay. For the second part of this project, the detection of PrPTSE in blood cells from primate infected with vCJD was performed. Infectivityin primate blood samples was evidenced through bioassayin conventional mice but not in Tg650 Hu PrP transgenic mice. In an independent project, those samples were also found positive through PrPTSE PMCA amplification (with this technique, detection in blood, white blood cells or buffy coat from non-human primate vCJD experimental models, was obtained even during the early preclinical stage of the incubation period). In addition, while developing protocols to detect PrPTSE in blood cells, the consortium reported the fact that blood storage might affect the detection of PrPC and potentially a non-specific binding of “PrPTSE antibody”.