Patent ID: 7166471

Claim:
A method for detecting, in body fluids, misfolded proteinaceous particles comprising a predominantly beta-sheet secondary structure, said method comprising: (a) obtaining a test specimen comprising body fluids; (b) adding a propagation catalyst to the test specimen, thereby forming a mixture, wherein: (i) the propagation catalyst is a peptide; (ii) the peptide has a predominantly alpha-helix and/or random coil secondary structure that interacts with misfolded proteinaceous particles, and (iii) the peptide undergoes a conformational shift that results in a decrease in alpha-helix and/or random coil secondary structure and an increase in beta-sheet secondary structure upon contact with misfolded proteinaceous particles or upon contact with another such propagation catalyst that has undergone such a conformational shift; (c) allowing the propagation catalyst and any misfolded proteinaceous particles in the test specimen to interact; and (d) detecting any increase in beta-sheet secondary structure in the mixture, the increase being due, at least in part, to an increase in beta-sheet secondary structure of the propagation catalyst, wherein any such increase indicates the presence of misfolded proteinaceous particles in the test specimen.