Insights into a preamyloid state by selectively trapping prion proteins in oligomeric forms
2009: 1 year / Grant: 28 000 euros
Detection of prions in biological fluids and tissues using Thienyl Pyrimidine compounds
2010: 1 year / Grant: 40 000 euros
PrP Blood Trap Development of a diagnosis assay of prions in blood by trapping infectious transient oligomers
2012: 18 months / Grant: 45 000 euros
Project: These consecutive projects aimed to understand how Thienyl Pyrimidine compounds could interact with PrPTSE and whether theycould be used to improve PrPTSE detection. The rational was that the stabilization of multimeric PrPTSE visualized by the presence of rSDS-oligomers (SDS resistant) of PrPTSE by western blot could constitute a relevant tool for the identification of prion infected samples.
Main results and related published data: Following virtual and cellular screenings, V. Perrier
has identified several thienyl pyrimidine compounds that trigger and stabilize PrPSc oligomers.
Thienyl pyrimidine compounds were shown by J. Torrent to interact with the pathological isoform PrPTSE, either with small PrPTSE entities or large aggregates that are present in cells and brain homogenates. This interaction triggered the appearance of SDS-resistant PrP(27-30) dimers and trimers after PK digestion and denaturation resulting thus in a small decrease in prion infectivity of the sample. The P30 compound and the quaterthiophene-bis-triazine P30 derivative compound, called MR100, were then shown to improve the detection of PrPTSE. The most impressive results were obtained with the MR100 compound since subnanomolar concentrations of MR100 could increase the level of oligomeric PrPTSE in cell culture models. A Rapid Centrifugation Assay consisting of preincubating brain samples from different species (hamster, mouse, human …), with MR100 followed by a shortcentrifugation step at 8000g, allowed the detection of all rSDS-PrPTSE oligomers in prion-infected brain homogenates, particularly in brain samples from sCJD and vCJD patients.
The RCA test developed with MR100 is free of proteinase K digestion step, allowing to detect all the PK sensitive PrPSc species. They also have obtained a correlation between the amount of rSDSPrPTSE oligomers and the duration of the symptomatic phase of the disease in CJD patients.
Moreover they have been able to show the potential of MR100 to sequestrate and trap prion infectivity from prion infected samples suggesting a potential of MR100 for prion decontamination.