Recently published data show that the Prionics antibody 15B3 could enable earlier diagnosis of prion disorders. Furthermore, the application area of the antibody may be extendable to many more prion disorders. Taken together, these findings make the antibody particularly suited for the detection of prion disorders in a blood test.
A recent study by Biasini et al. shows that the conformation-specific Prionics antibody 15B3 and three other, motif grafted, antibodies are particularly selective for multiple types of prion aggregates and could be therefore more widely applicable than presumed so far. This data is described in a paper published online on March 26, 2008 in the Journal of Neurochemistry.
15B3 is an antibody that specifically recognizes the aberrantly folded form of the PrP protein and not the normal PrP molecule (PrPC). The specificity of the antibody, which was developed by the Prionics founders in 1997, was confirmed in the study of Biasini and colleagues. These authors showed that 15B3 recognizes all prion aggregates tested and speculate that, because the 15B3 can detect intermediate, in addition to PrPSc aggregates, it could also diagnose prion disease at earlier stages by binding aberrantly formed prion proteins before they become infectious. Furthermore, the antibody should enable diagnosis of a much wider range of prion disorders - including familial cases.
Blood test
A further advantage of this conformation-specific antibody is that the 15B3 is capable of detecting PrPvCJD in brain homogenates without the need for protein digestion, since it discriminates between PrPC and PrPSc. This is of considerable importance for its application in blood because it has been shown that prion infectivity in blood is sensitive to protease digestion and therefore might not be detected in methods using proteases. Prionics is currently developing a blood test for the specific detection of the disease causing prion protein in blood using the antibody 15B3.
