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Mazza M, Tran L, Loprevite D, Cavarretta MC, Meloni D, Dell’Atti L, Våge J, Madslien K, Vuong TT, Bozzetta E, Benestad SL. Are rapid tests and confirmatory western blot used for cattle and small ruminants TSEs reliable tools for the diagnosis of Chronic Wasting Disease in Europe? PLoS One 2023; 18:e0286266. [PMID: 37647272 PMCID: PMC10468065 DOI: 10.1371/journal.pone.0286266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 05/12/2023] [Indexed: 09/01/2023] Open
Abstract
The first case of CWD in Europe was detected in a Norwegian reindeer in 2016, followed later by two CWD cases in Norwegian moose. To prevent the potential spread of CWD to the EU, the European Commission (Regulation EU 2017_1972) implemented a CWD surveillance programme in cervids in the six countries having reindeer and or moose (Estonia, Finland, Latvia, Lithuania, Poland, and Sweden). Each country had to test a minimum of 3000 cervids for CWD using diagnostic rapid tests approved by the EC Regulation. Experimental transmission studies in rodents have demonstrated that the CWD strains found in Norwegian reindeer are different from those found in moose and that these European strains are all different from the North American ones. Data on the performances of authorised rapid tests are limited for CWD (from North America) and are currently minimal for CWD from Europe, due to the paucity of positive material. The aim of this study was to evaluate the diagnostic performances of three of the so-called "rapid" tests, commercially available and approved for TSE diagnosis in cattle and small ruminants, to detect the CWD strains circulating in Europe. The performances of these three tests were also compared to two different confirmatory western blot methods. Using parallel testing on the same panel of available samples, we evaluated here the analytical sensitivity of these methods for TSE diagnosis of CWD in Norwegian cervids tissues. Our results show that all the methods applied were able to detect the CWD positive samples even if differences in analytical sensitivity were clearly observed. Although this study could not assess the test accuracy, due to the small number of samples available, it is conceivable that the rapid and confirmatory diagnostic systems applied for CWD surveillance in Northern Europe are reliable tools.
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Affiliation(s)
- Maria Mazza
- European Reference Laboratory for Transmissible Spongiform Encephalopathies - Italian Reference Laboratory for Transmissible Spongiform Encephalopathies, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, Turin, Italy
| | - Linh Tran
- World Organisation for Animal Health (WOAH, founded as OIE) - Reference Laboratory for Chronic Wasting Disease, Norwegian Veterinary Institute, Oslo, Norway
| | - Daniela Loprevite
- European Reference Laboratory for Transmissible Spongiform Encephalopathies - Italian Reference Laboratory for Transmissible Spongiform Encephalopathies, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, Turin, Italy
| | - Maria C. Cavarretta
- European Reference Laboratory for Transmissible Spongiform Encephalopathies - Italian Reference Laboratory for Transmissible Spongiform Encephalopathies, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, Turin, Italy
| | - Daniela Meloni
- European Reference Laboratory for Transmissible Spongiform Encephalopathies - Italian Reference Laboratory for Transmissible Spongiform Encephalopathies, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, Turin, Italy
| | - Luana Dell’Atti
- European Reference Laboratory for Transmissible Spongiform Encephalopathies - Italian Reference Laboratory for Transmissible Spongiform Encephalopathies, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, Turin, Italy
| | - Jørn Våge
- World Organisation for Animal Health (WOAH, founded as OIE) - Reference Laboratory for Chronic Wasting Disease, Norwegian Veterinary Institute, Oslo, Norway
| | - Knut Madslien
- World Organisation for Animal Health (WOAH, founded as OIE) - Reference Laboratory for Chronic Wasting Disease, Norwegian Veterinary Institute, Oslo, Norway
| | - Tram T. Vuong
- World Organisation for Animal Health (WOAH, founded as OIE) - Reference Laboratory for Chronic Wasting Disease, Norwegian Veterinary Institute, Oslo, Norway
| | - Elena Bozzetta
- European Reference Laboratory for Transmissible Spongiform Encephalopathies - Italian Reference Laboratory for Transmissible Spongiform Encephalopathies, Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d’Aosta, Turin, Italy
| | - Sylvie L. Benestad
- World Organisation for Animal Health (WOAH, founded as OIE) - Reference Laboratory for Chronic Wasting Disease, Norwegian Veterinary Institute, Oslo, Norway
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Defining the Prion Type of Fatal Familial Insomnia. Pathogens 2021; 10:pathogens10101293. [PMID: 34684242 PMCID: PMC8539405 DOI: 10.3390/pathogens10101293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 09/08/2021] [Accepted: 09/22/2021] [Indexed: 12/02/2022] Open
Abstract
Fatal familial insomnia (FFI) belongs to the genetic human transmissible spongiform encephalopathies (TSE), such as genetic Creutzfeldt-Jakob disease (CJD) or Gerstmann-Straeussler-Scheinker syndrome (GSS). Here, we analyzed the properties of the pathological prion protein in six FFI cases by Western blot analysis, a protein aggregate stability assay, and aggregate deposition characteristics visualized with the paraffin-embedded tissue blot. While in all cases the unglycosylated fragment in Western blot analysis shared the same size with sporadic CJD prion type 2, the reticular/synaptic deposition pattern of the prion aggregates resembled the ones found in sporadic CJD type 1 (CJD types according to the Parchi classification from 1999). Regarding the conformational stability against denaturation with GdnHCl, FFI prion aggregates resembled CJD type 1 more than type 2. Our results suggest that the size of the proteinase-K-resistant fragments is not a valid criterion on its own. Additional criteria supplying information about conformational differences or similarities need to be taken into account. FFI may resemble a prion type with its own conformation sharing properties partly with type 1 and type 2 prions.
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Preliminary Evidence of a Molecular Detection Method to Analyze Bacterial DNA as a Quality Indicator in Cosmetics. COSMETICS 2020. [DOI: 10.3390/cosmetics7030054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cosmetics are a category of widely consumed and distributed products, and their manufacture is always subject to specific guidelines. Quality Control (QC) tests provide information supporting the absence of injurious organisms and regarding the microbiological stability of cosmetics. The microbiological risk analysis is typically performed using the plate count method, which is a time-consuming and operator-dependent approach. Molecular technologies allow a deeper and more sensitive testing than traditional cultures. The demand for rapid and sensitive methods is recently increasing. The aim of our study was to compare different DNA extraction methods in order to detect and quantify bacterial load in cosmetics using a qPCR system. Known numbers of microorganisms were spiked into six different cosmetics to simulate contaminated samples. DNA was extracted with seven extraction kits and then quantified by real-time qPCR. Results revealed differences in terms of cell recovery, DNA yield, and quality. The bead-beating approaches were the most suitable in our molecular workflow and lead to good quality DNA for analysis by qPCR within four hours. Combined with mechanical extraction, qPCR may represent an efficient and easy method for microorganism identification in cosmetics, and can be automated. This approach also is also applicable for the detection of probiotics used as beneficial biological components in cosmetic products. The results of our molecular method provided preliminary evidences for the rapid identification of cells (10–100) and nucleic acids in complex preparations employed for human health, in compliance with regulatory limits. The suggested methodology is easy, fast, and sensitive. Its scalability allows serial microbiological evaluation at every manufacturing step.
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Esmaili M, Tancowny BP, Wang X, Moses A, Cortez LM, Sim VL, Wille H, Overduin M. Native nanodiscs formed by styrene maleic acid copolymer derivatives help recover infectious prion multimers bound to brain-derived lipids. J Biol Chem 2020; 295:8460-8469. [PMID: 32358064 DOI: 10.1074/jbc.ra119.012348] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 04/14/2020] [Indexed: 11/06/2022] Open
Abstract
Prions are lipidated proteins that interact with endogenous lipids and metal ions. They also assemble into multimers and propagate into the infectious scrapie form known as PrPSc The high-resolution structure of the infectious PrPSc state remains unknown, and its analysis largely relies on detergent-based preparations devoid of endogenous ligands. Here we designed polymers that allow isolation of endogenous membrane:protein assemblies in native nanodiscs without exposure to conventional detergents that destabilize protein structures and induce fibrillization. A set of styrene-maleic acid (SMA) polymers including a methylamine derivative facilitated gentle release of the infectious complexes for resolution of multimers, and a thiol-containing version promoted crystallization. Polymer extraction from brain homogenates from Syrian hamsters infected with Hyper prions and WT mice infected with Rocky Mountain Laboratories prions yielded infectious prion nanoparticles including oligomers and microfilaments bound to lipid vesicles. Lipid analysis revealed the brain phospholipids that associate with prion protofilaments, as well as those that are specifically enriched in prion assemblies captured by the methylamine-modified copolymer. A comparison of the infectivity of PrPSc attached to SMA lipid particles in mice and hamsters indicated that these amphipathic polymers offer a valuable tool for high-yield production of intact, detergent-free prions that retain in vivo activity. This native prion isolation method provides an avenue for producing relevant prion:lipid targets and potentially other proteins that form multimeric assemblies and fibrils on membranes.
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Affiliation(s)
- Mansoore Esmaili
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Brian P Tancowny
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Xiongyao Wang
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Audric Moses
- Lipidomics Core Facility, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Leonardo M Cortez
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Division of Neurology, Department of Medicine, Centre for Prions and Protein Folding Diseases, and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Valerie L Sim
- Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.,Division of Neurology, Department of Medicine, Centre for Prions and Protein Folding Diseases, and Neuroscience and Mental Health Institute, University of Alberta, Edmonton, Alberta, Canada
| | - Holger Wille
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada .,Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada
| | - Michael Overduin
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
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Leske H, Hornemann S, Herrmann US, Zhu C, Dametto P, Li B, Laferriere F, Polymenidou M, Pelczar P, Reimann RR, Schwarz P, Rushing EJ, Wüthrich K, Aguzzi A. Protease resistance of infectious prions is suppressed by removal of a single atom in the cellular prion protein. PLoS One 2017; 12:e0170503. [PMID: 28207746 PMCID: PMC5313174 DOI: 10.1371/journal.pone.0170503] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Accepted: 12/16/2016] [Indexed: 11/18/2022] Open
Abstract
Resistance to proteolytic digestion has long been considered a defining trait of prions in tissues of organisms suffering from transmissible spongiform encephalopathies. Detection of proteinase K-resistant prion protein (PrPSc) still represents the diagnostic gold standard for prion diseases in humans, sheep and cattle. However, it has become increasingly apparent that the accumulation of PrPSc does not always accompany prion infections: high titers of prion infectivity can be reached also in the absence of protease resistant PrPSc. Here, we describe a structural basis for the phenomenon of protease-sensitive prion infectivity. We studied the effect on proteinase K (PK) resistance of the amino acid substitution Y169F, which removes a single oxygen atom from the β2–α2 loop of the cellular prion protein (PrPC). When infected with RML or the 263K strain of prions, transgenic mice lacking wild-type (wt) PrPC but expressing MoPrP169F generated prion infectivity at levels comparable to wt mice. The newly generated MoPrP169F prions were biologically indistinguishable from those recovered from prion-infected wt mice, and elicited similar pathologies in vivo. Surprisingly, MoPrP169F prions showed greatly reduced PK resistance and density gradient analyses showed a significant reduction in high-density aggregates. Passage of MoPrP169F prions into mice expressing wt MoPrP led to full recovery of protease resistance, indicating that no strain shift had taken place. We conclude that a subtle structural variation in the β2–α2 loop of PrPC affects the sensitivity of PrPSc to protease but does not impact prion replication and infectivity. With these findings a specific structural feature of PrPC can be linked to a physicochemical property of the corresponding PrPSc.
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Affiliation(s)
- Henning Leske
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Simone Hornemann
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Uli Simon Herrmann
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Caihong Zhu
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Paolo Dametto
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Bei Li
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Florent Laferriere
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland
| | - Magdalini Polymenidou
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland
| | - Pawel Pelczar
- Institute of Molecular Biology and Biophysics, ETH Zurich, Otto-Stern-Weg 5, Zurich, Switzerland
| | - Regina Rose Reimann
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Petra Schwarz
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Elisabeth Jane Rushing
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
| | - Kurt Wüthrich
- Department of Integrative Structural and Computational Biology and Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, United States of America
- * E-mail: (AA); , (KW)
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zurich, University of Zurich, Schmelzbergstrasse 12, Zurich, Switzerland
- * E-mail: (AA); , (KW)
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Rasmussen J, Gilroyed BH, Reuter T, Dudas S, Neumann NF, Balachandran A, Kav NNV, Graham C, Czub S, McAllister TA. Can plants serve as a vector for prions causing chronic wasting disease? Prion 2015; 8:136-42. [PMID: 24509640 DOI: 10.4161/pri.27963] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Prions, the causative agent of chronic wasting disease (CWD) enter the environment through shedding of bodily fluids and carcass decay, posing a disease risk as a result of their environmental persistence. Plants have the ability to take up large organic particles, including whole proteins, and microbes. This study used wheat (Triticum aestivum L.) to investigate the uptake of infectious CWD prions into roots and their transport into aerial tissues. The roots of intact wheat plants were exposed to infectious prions (PrP(TSE)) for 24 h in three replicate studies with PrP(TSE) in protein extracts being detected by western blot, IDEXX and Bio-Rad diagnostic tests. Recombinant prion protein (PrP(C)) bound to roots, but was not detected in the stem or leaves. Protease-digested CWD prions (PrP(TSE)) in elk brain homogenate interacted with root tissue, but were not detected in the stem. This suggests wheat was unable to transport sufficient PrP(TSE) from the roots to the stem to be detectable by the methods employed. Undigested PrP(TSE) did not associate with roots. The present study suggests that if prions are transported from the roots to the stems it is at levels that are below those that are detectable by western blot, IDEXX or Bio-Rad diagnostic kits.
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Xu S, Reuter T, Gilroyed BH, Mitchell GB, Price LM, Dudas S, Braithwaite SL, Graham C, Czub S, Leonard JJ, Balachandran A, Neumann NF, Belosevic M, McAllister TA. Biodegradation of prions in compost. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:6909-6918. [PMID: 24819143 DOI: 10.1021/es500916v] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Composting may serve as a practical and economical means of disposing of specified risk materials (SRM) or animal mortalities potentially infected with prion diseases (transmissible spongiform encephalopathies, TSE). Our study investigated the degradation of prions associated with scrapie (PrP(263K)), chronic waste disease (PrP(CWD)), and bovine spongiform encephalopathy (PrP(BSE)) in lab-scale composters and PrP(263K) in field-scale compost piles. Western blotting (WB) indicated that PrP(263K), PrP(CWD), and PrP(BSE) were reduced by at least 2 log10, 1-2 log10, and 1 log10 after 28 days of lab-scale composting, respectively. Further analysis using protein misfolding cyclic amplification (PMCA) confirmed a reduction of 2 log10 in PrP(263K) and 3 log10 in PrP(CWD). Enrichment for proteolytic microorganisms through the addition of feather keratin to compost enhanced degradation of PrP(263K) and PrP(CWD). For field-scale composting, stainless steel beads coated with PrP(263K) were exposed to compost conditions and removed periodically for bioassays in Syrian hamsters. After 230 days of composting, only one in five hamsters succumbed to TSE disease, suggesting at least a 4.8 log10 reduction in PrP(263K) infectivity. Our findings show that composting reduces PrP(TSE), resulting in one 50% infectious dose (ID50) remaining in every 5600 kg of final compost for land application. With these considerations, composting may be a viable method for SRM disposal.
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Affiliation(s)
- Shanwei Xu
- Agriculture and Agri-Food Canada, Lethbridge Research Centre , Lethbridge, Alberta T1J 4B1, Canada
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Vrentas CE, Greenlee JJ, Baron T, Caramelli M, Czub S, Nicholson EM. Stability properties of PrP(Sc) from cattle with experimental transmissible spongiform encephalopathies: use of a rapid whole homogenate, protease-free assay. BMC Vet Res 2013; 9:167. [PMID: 23945217 PMCID: PMC3751458 DOI: 10.1186/1746-6148-9-167] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 08/12/2013] [Indexed: 12/01/2022] Open
Abstract
Background Transmissible Spongiform Encephalopathies (TSEs), including scrapie in sheep, chronic wasting disease (CWD) in cervids, transmissible mink encephalopathy (TME), and bovine spongiform encephalopathy (BSE), are fatal diseases of the nervous system associated with accumulation of misfolded prion protein (PrPSc). Different strains of TSEs exist, associated with different PrPSc conformations that can be probed by the stability assay, in which PrPSc is treated with increasing concentrations of the denaturant guanidine hydrochloride (GdnHCl). Results Here, we provide the first comprehensive application of a rapid, protease-free version of the GdnHCl stability assay to brain tissue from cattle experimentally infected with various TSE isolates. Consistent with previous findings from a single Japanese isolate, the L-type isolates of BSE are not distinguishable from classical BSE in this assay. In contrast, H-type isolates of BSE, including our unique isolate of E211K BSE, exhibit higher stability than classical BSE, suggesting that its increased protection against protease digestion at the BSE N-terminus is associated with a higher stability in GdnHCl. While the difference in stability in our version of the assay is likely not large enough for effective use in a diagnostic laboratory setting, the use of alternative experimental conditions may enhance this effect. TSEs from other natural host species that have been passaged in cattle, including CWD and TME, were not distinguishable from classical BSE, while isolates of cattle passaged scrapie exhibited a slight increase in stability as compared to classical BSE. Conclusions These results suggest that the core of PrPSc, as probed in this assay, has similar stability properties among cattle-passaged TSE isolates and that the conformational differences that lead to changes in the proteinase K cleavage site do not cause large changes in the stability of PrPSc from TSE-affected cattle. However, the stability differences observed here will provide a basis of comparison for new isolates of atypical BSE observed in the future and in other geographic locations, especially in the case of H-type BSE.
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Affiliation(s)
- Catherine E Vrentas
- Virus and Prion Disease Research Unit, National Animal Disease Center, USDA, Agricultural Research Service, Ames, IA 50010, USA
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Filtration of Protein Aggregates Increases the Accuracy for Diagnosing Prion Diseases in Brain Biopsies. J Neuropathol Exp Neurol 2013; 72:758-67. [DOI: 10.1097/nen.0b013e31829d2799] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Margalith I, Suter C, Ballmer B, Schwarz P, Tiberi C, Sonati T, Falsig J, Nyström S, Hammarström P, Aslund A, Nilsson KPR, Yam A, Whitters E, Hornemann S, Aguzzi A. Polythiophenes inhibit prion propagation by stabilizing prion protein (PrP) aggregates. J Biol Chem 2012; 287:18872-87. [PMID: 22493452 DOI: 10.1074/jbc.m112.355958] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Luminescent conjugated polymers (LCPs) interact with ordered protein aggregates and sensitively detect amyloids of many different proteins, suggesting that they may possess antiprion properties. Here, we show that a variety of anionic, cationic, and zwitterionic LCPs reduced the infectivity of prion-containing brain homogenates and of prion-infected cerebellar organotypic cultured slices and decreased the amount of scrapie isoform of PrP(C) (PrP(Sc)) oligomers that could be captured in an avidity assay. Paradoxically, treatment enhanced the resistance of PrP(Sc) to proteolysis, triggered the compaction, and enhanced the resistance to proteolysis of recombinant mouse PrP(23-231) fibers. These results suggest that LCPs act as antiprion agents by transitioning PrP aggregates into structures with reduced frangibility. Moreover, ELISA on cerebellar organotypic cultured slices and in vitro conversion assays with mouse PrP(23-231) indicated that poly(thiophene-3-acetic acid) may additionally interfere with the generation of PrP(Sc) by stabilizing the conformation of PrP(C) or of a transition intermediate. Therefore, LCPs represent a novel class of antiprion agents whose mode of action appears to rely on hyperstabilization, rather than destabilization, of PrP(Sc) deposits.
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Affiliation(s)
- Ilan Margalith
- Institute of Neuropathology, University Hospital of Zurich, CH-8091 Zurich, Switzerland
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