Patent ID: 7429463

Claim:
A method for the differential diagnosis of TSSEs caused by UTA strains by detecting the PrPs-res associated with the various UTA strains, comprising: (a) detecting PrP-res in a first fraction of a biological sample, in accordance with steps (1) to (3): (1) treating a sample suspected of containing a prion with proteinase K for a time and under conditions that completely degrade normal prion protein (Prp-sen), but which only partially digest abnormal prion protein (PrP-res) so that all or some of the octapeptide motif repeats comprising P(H/Q)GGG(-/T)WGQ (SEQ ID NO: 1) in the abnormal prion protein (Prp-res) are retained, (2) contacting said sample from (1) with a ligand which binds to said octapeptide motifs for a time and under conditions sufficient for complex formation between said ligand and polypeptides containing said octapeptide motif, and (3) detecting complex formation, wherein complex formation is indicative of the presence of TSSE or a prion disease; and then: (b) for each sample for which the presence of an octapeptide motif repeats/ligand complex is detected in step (a): treating a second fraction of said sample with at least one proteinase K in such a way that the majority of the octapeptide motif repeats are eliminated for the PrP-res associated with at least one strain of interest, in particular the BSE strain, and such that all of the PrPs-res associated with the other UTA strains conserve all or some of said octapeptide motif repeats, bringing said second fraction of said sample treated into contact with a ligand capable of specifically recognizing said octapeptide motif repeats, and detecting the possible presence of the octapeptide motif repeats/ligand complex.