Biochemical analysis methods
| Method | Function of test | Advantages | Disadvantages | References |
| 1. Western blot (WB) | Detection of protease-resistant PrPSc | Standard method used in the diagnosis of prion diseases | Relatively low analytical sensitivity | 22–24 |
| 2. Sodium phosphotungstic acid (NaPTA) precipitation/western blotting | Concentration and detection of protease-resistant PrPSc | Can detect low levels of PrPSc, for example, in vCJD spleen and sCJD muscle | Not tested for use in routine diagnostics or screening | 2 25 26 |
| 3. Conformation-dependent immunoassay (CDI) | Detection of PrPSc based on concealed epitopes that are exposed when PrPSc is denatured | Can detect protease-sensitive forms of PrPSc | Not tested for use in routine diagnostics or screening | 28 29 |
| 4. Real-time quaking-induced conversion (RT-QuIC) | Uses incubation and shaking to recapitulate and accelerate prion replication in vitro using recombinant prion protein (PrP) substrate | Ultra-sensitive for detecting low levels of sCJD PrPSc | Less able to detect vCJD PrPSc | 32–34 |
| 5. Protein misfolded cyclic amplification (PMCA) | Uses incubation and sonication to recapitulate and accelerate prion replication in vitro using brain cellular prion protein PrPC substrate | Ultra-sensitive for detecting low levels of vCJD PrPSc | Less sensitive for sCJD PrPSc in our hands | 30 31 |
CJD, Creutzfeldt-Jakob disease; PrP, prion protein; PrPSc, abnormal misfolded form of the PrP; sCJD, sporadic CJD; vCJD, Variant CJD.