Figure 1

Overview of prion fibril multiplication and two prion amplification assays. (a) Schematic of misfolded prion fibril growth. The initial misfolded PrP (PrP^CWD) causes native PrP to misfold. (b) Overview of RT-QuIC and MN-QuIC. RT-QuIC: Seeds originating from tissue samples of cervids (whether CWD negative or CWD positive) are added to recombinant PrP solutions. These solutions are then shaken and incubated for ~ 48 h (depending on sample type). If present, misfolded PrP fibrils (PrP^CWD) from CWD positive tissue induce conformational changes of the recombinant PrP. Amplification results are read in real-time with ThT fluorescence. MN-QuIC: After 24 h amplification, products are diluted and added to an AuNP solution. CWD positive samples result in a red solution (peak absorbance wavelength ~ 516 nm) while CWD negative solutions are blue/purple (peak absorbance wavelength ~ 560 nm).