Related Experiment Video
Updated: Mar 22, 2026
Real-time Quaking-induced Conversion Assay for Detection of CWD Prions in Fecal Material
Published on: September 29, 2017
A direct assessment of human prion adhered to steel wire using real-time quaking-induced conversion
Tsuyoshi Mori1, Ryuichiro Atarashi1, Kana Furukawa1
1Department of Molecular Microbiology and Immunology, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
Abstract:
Accidental transmission of prions during neurosurgery has been reported as a consequence of re-using contaminated surgical instruments. Several decontamination methods have been studied using the 263K-hamster prion; however, no studies have directly evaluated human prions. A newly developed in vitro amplification system, designated real-time quaking-induced conversion (RT-QuIC), has allowed the activity of abnormal prion proteins to be assessed within a few days. RT-QuIC using human recombinant prion protein (PrP) showed high sensitivity for prions as the detection limit of our assay was estimated as 0.12 fg of active prions. We applied this method to detect human prion activity on stainless steel wire. When we put wires contaminated with human Creutzfeldt-Jakob disease brain tissue directly into the test tube, typical PrP-amyloid formation was observed within 48 hours, and we could detect the activity of prions at 50% seeding dose on the wire from 10(2.8) to 10(5.8) SD50. Using this method, we also confirmed that the seeding activities on the wire were removed following treatment with NaOH. As seeding activity closely correlated with the infectivity of prions using the bioassay, this wire-QuIC assay will be useful for the direct evaluation of decontamination methods for human prions.
Insights
A new assay can detect human prions on surgical wires, confirming that NaOH effectively removes them. This method aids in evaluating decontamination procedures for preventing prion transmission during neurosurgery.
Area of Science:
- Neuroscience
- Biochemistry
- Infectious Diseases
Background:
- Prion diseases like Creutzfeldt-Jakob disease (CJD) pose a risk of iatrogenic transmission through contaminated surgical instruments.
- Evaluating the effectiveness of decontamination methods for human prions on surgical tools is crucial but challenging.
Purpose of the Study:
- To develop and validate a sensitive in vitro assay for detecting human prion seeding activity on stainless steel wires.
- To assess the efficacy of sodium hydroxide (NaOH) in removing human prion activity from contaminated wires.
Main Methods:
- Utilized a real-time quaking-induced conversion (RT-QuIC) assay with human recombinant prion protein (PrP) to detect prion activity.
- Applied the assay to stainless steel wires contaminated with human CJD brain tissue.
- Evaluated the removal of prion seeding activity after NaOH treatment.
Main Results:
- The RT-QuIC assay demonstrated high sensitivity, with a detection limit of 0.12 fg of active prions.
- Human prion seeding activity was successfully detected on contaminated wires within 48 hours.
- NaOH treatment effectively removed prion seeding activity from the wires.
Conclusions:
- The developed wire-QuIC assay is a sensitive tool for directly evaluating the decontamination of human prions on surgical instruments.
- This assay can aid in validating sterilization protocols to prevent prion transmission in healthcare settings.
