Sensitive detection of pathological seeds of a-synuclein, tau and prion protein on solid surfaces

Authors: ORRÚ, CHRISTINA - National Institutes Of Health (NIH); GROVEMAN, ANDREW - National Institutes Of Health (NIH); HUGHSON, ANDREW - National Institutes Of Health (NIH); BARRIO, TOMÁS - National Veterinary School Of Toulouse, France; ISIOFIA, KACHI - National Institute On Aging (NIA, NIH); RACE, BRENT - National Institutes Of Health (NIH); FERREIRA, NATALIA - Rocky Mountain Laboratories National Institute Of Allergy And Infectious Diseases (NIAID); GAMBETTI, PIERLUIGI - Case Western Reserve University (CWRU); Schneider, David; MASUJIN, KENTARO - National Institute Of Animal Health - Japan (NIAH, NARO); MIYAZAWA, KOHTARO - National Institute Of Animal Health - Japan (NIAH, NARO); GHETTI, BERNARDINO - Indiana University; ZANUSSO, GIANLUIGI - University Of Verona; CAUGHEY, BYRON - National Institutes Of Health (NIH)

Submitted to: PLoS Pathogens
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/16/2024
Publication Date: 4/19/2024
Citation: Orrú, C.D., Groveman, A.R., Hughson, A.G., Barrio, T., Isiofia, K., Race, B., Ferreira, N.C., Gambetti, P., Schneider, D.A., Masujin, K., Miyazawa, K., Ghetti, B., Zanusso, G., Caughey, B. 2024. Sensitive detection of pathological seeds of a-synuclein, tau and prion protein on solid surfaces. PLoS Pathogens. 20(4). Article e1012175. https://doi.org/10.1371/journal.ppat.1012175.
DOI: https://doi.org/10.1371/journal.ppat.1012175

Interpretive Summary: The presence of prion or prion-like aggregates on solid surfaces may be bio-hazardous to humans and animals. A practical method for detecting the presence of these aggregates on large surfaces is needed. This study transiently applied a sampling medium to stainless steel and acrylic surfaces contaminated with dried-on diseased tissue, including objects stored contaminated for one year. The sampling medium was removed and tested using an amplification assay known as the real-time quaking-induced conversion (RT-QuIC) assay. Surface contaminations by aggregates from a broad spectrum of prion and prion-like diseases were detected in the sampling medium with high sensitivity and specificity. Surgical instrument contamination withstanding a standard disinfection procedure was also demonstrated. This study demonstrated practical protocols to detect solid surface contamination by aggregates associated with prion diseases in sheep, cattle, deer, and humans and by aggregates associated with Parkinson's and Alzheimer's (prion-like) diseases in humans.

Technical Abstract: Prions or prion-like aggregates such as those composed of PrP, a-synuclein, and tau are key features of proteinopathies such as prion, Parkinson’s and Alzheimer’s diseases, respectively. Their presence on solid surfaces may be biohazardous under some circumstances. PrP prions bound to solids are detectable by ultrasensitive real-time quaking-induced conversion (RT-QuIC) assays if the solids can be immersed in assay wells or the prions transferred to pads. Here we show that prion-like seeds can remain detectable on steel wires for at least a year, or even after enzymatic cleaning and sterilization. We also show that contamination of larger objects with pathological seeds of a-synuclein, tau, and PrP can be detected by simply assaying a sampling medium that has been transiently applied to the surface. Human a-synuclein seeds in dementia with Lewy bodies brain tissue were detected by a-synuclein RT-QuIC after drying of tissue dilutions with concentrations as low as 10-6 onto stainless steel. Tau RT-QuIC detected tau seeding activity on steel exposed to Alzheimer’s disease brain tissue diluted as much as a billion fold. Prion RT-QuIC assays detected seeding activity on plates exposed to brain dilutions as extreme as 10-5–10-8 from prion-affected humans, sheep, cattle and cervids. Sampling medium collected from surgical instruments used in necropsies of sporadic Creutzfeldt-Jakob disease-infected transgenic mice was positive down to 10-6 dilution. Sensitivity for prion detection was not sacrificed by omitting the recombinant PrP substrate from the sampling medium during its application to a surface and subsequent storage as long as the substrate was added prior to performing the assay reaction. Our findings demonstrate practical prototypic surface RT-QuIC protocols for the highly sensitive detection of pathologic seeds of a-synuclein, tau, and PrP on solid objects.