Diagnostic workshop on Real-time quaking-induced conversion (RT-QuIC) to enhance MS capacity to diagnose CJD

​Real-time quaking-induced conversion (RT-QuIC) is increasingly being used as an assay of choice to detect the abnormal form of prion protein (PrPSc) in easily accessible specimens such as cerebrospinal fluid (CSF).

In order to enhance the understanding of the methodology and its consistent application, a training day on the analytical and clinical aspects of analysing cerebrospinal fluid (CSF) samples by RT-QuIC in the investigation of patents with suspected sporadic CJD (sCJD) was held at the National CJD Research & Surveillance Unit (NCJDRSU). The workshop was funded by ECDC as part of the ongoing activities to support identification and monitoring of human TSE in the EU/EEA by the EUROCJD network. The network is currently coordinated by NCJDRSU.

The workshop agenda included speakers on both the clinical and analytical aspects of establishing RT-QuIC as well as the analytical considerations of recombinant prion protein (PrP) production. There were three discussion groups that covered these three topics (agenda appended- see Annex 1). Invitations to the training day were sent to all EU/EEA countries and there were 14 attendees from 8 countries.

The meeting was introduced by Professor RG Will who presented an overview of RT-QuIC, which is now considered to be a major diagnostic advance in the investigation of patients with sCJD, Professor Will emphasised the significant improvement in diagnostic accuracy of RT-QuIC over other pre-mortem diagnostic tests such as CSF 14-3-3, MRI or EEG.

 

Dr A Green gave a presentation on the clinical aspects of RT-QuIC describing the results from a retrospective study and the results from a continuing prospective audit of the clinical utility of RT-QuIC.  Dr L McGuire provided a detailed description of the analytical protocols used for the RT-QuIC undertaken at the NCJDRSU, including technical pit-falls and useful troubleshooting guides.  This was followed by a presentation on the production of hamster rPrP given by Dr J Eastlake and Dr D Jackson from the Bristol Institute of Transfusion Sciences.  This presentation covered the technical aspects and the steps taken to optimise both the quality and volume of rPrP produced.

 

The following day the attendees were split into three small discussion groups.  The first discussion group covered a visit to the laboratory to see first-hand the set-up required for RT-QuIC and to discuss in detail both the health and safety aspects of the technique and the practical issues involved.   The second discussion group covered the technical aspects of recombinant PrP production.  The final discussion group involved the interpretation of RT-QuIC, and involved looking at the analytical data from the most recent RT-QuIC runs.

 

After lunch Dr A Green gave a presentation describing the reproducibility of the RT-QuIC.  This included results obtained from two international ring-trials.  This was followed by the final presentation looking at individual cases where the RT-QuIC result had proved to be invaluable in the clinical evaluation of the patient.

 

Professor RG Will closed the meeting with an overview of the clinical utility of the RT-QuIC and how important RT-QuIC is in the surveillance of sCJD.

 
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EuroCJD

 
Agenda