Ring trial of 2nd generation RT-QuIC diagnostic tests for sporadic CJD.

Objective: Real-time quaking-induced conversion (RT-QuIC) assays detect prion-seeding activity in a variety of human biospecimens, including cerebrospinal fluid and olfactory mucosa swabs. The assay has shown high diagnostic accuracy in patients with prion disorders. Recently, advances in these tests have led to markedly improved diagnostic sensitivity and reduced assay times.

Amplification techniques and diagnosis of prion diseases.

Protein misfolding cyclic amplification assay (PMCA) and real-time quaking-induced conversion (RT-QuIC) are two amplification techniques based on the ability of PrPsc to induce a conformational change in PrP allowing the detection of minute amounts of PrPsc in body fluids or tissues. PMCA and RT-QuIC have different ability to amplify PrPsc from sporadic, variant and genetic forms of Creutzfeldt-Jakob disease (CJD). PMCA readily amplifies PrPsc from variant CJD (vCJD) tissue while RT-QuIC easily amplifies PrPsc from sporadic CJD (sCJD) patient tissues.

Detection and partial discrimination of atypical and classical bovine spongiform encephalopathies in cattle and primates using real-time quaking-induced conversion assay.

The transmission of classical bovine spongiform encephalopathy (C-BSE) through contaminated meat product consumption is responsible for variant Creutzfeldt-Jakob disease (vCJD) in humans. More recent and atypical forms of BSE (L-BSE and H-BSE) have been identified in cattle since the C-BSE epidemic. Their low incidence and advanced age of onset are compatible with a sporadic origin, as are most cases of Creutzfeldt-Jakob disease (CJD) in humans.

Cerebrospinal fluid real-time quaking-induced conversion is a robust and reliable test for sporadic creutzfeldt-jakob disease: An international study.

Real-time quaking-induced conversion (RT-QuIC) has been proposed as a sensitive diagnostic test for sporadic Creutzfeldt-Jakob disease; however, before this assay can be introduced into clinical practice, its reliability and reproducibility need to be demonstrated. Two international ring trials were undertaken in which a set of 25 cerebrospinal fluid samples were analyzed by a total of 11 different centers using a range of recombinant prion protein substrates and instrumentation. The results show almost complete concordance between the centers and demonstrate that RT-QuIC is a suitably reliable and robust technique for clinical practice.