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Yilmaz G, Morrill T, Pilot W, Ward C, Mitchell G, Soutyrine A, Dan H, Lin M, Guan J. Optimization of RT-QuIC Assay Duration for Screening Chronic Wasting Disease in White-Tailed Deer. Vet Sci 2024; 11:60. [PMID: 38393078 PMCID: PMC10891863 DOI: 10.3390/vetsci11020060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 02/25/2024] Open
Abstract
Real-time quaking-induced conversion (RT-QuIC) assays have become a common tool to detect chronic wasting disease (CWD) and are very sensitive provided the assay duration is sufficient. However, a prolonged assay duration may lead to non-specific signal amplification. The wide range of pre-defined assay durations in current RT-QuIC applications presents a need for methods to optimize the RT-QuIC assay. In this study, receiver operating characteristic (ROC) analysis was applied to optimize the assay duration for CWD screening in obex and retropharyngeal lymph node (RLN) tissue specimens. Two different fluorescence thresholds were used: a fixed threshold based on background fluorescence (Tstdev) and a max-point ratio (maximum/background fluorescence) threshold (TMPR) to determine CWD positivity. The optimal assay duration was 33 h for obex and 30 h for RLN based on Tstdev, and 29 h for obex and 32 h for RLN based on TMPR. The optimized assay durations were then evaluated for screening CWD in white-tailed deer from an affected farm. At a replicate level, using the optimized assay durations with TStdev and TMPR, the level of agreement with enzyme-linked immunosorbent assay (ELISA) was significantly higher (p < 0.05) than that when using a 40 h assay duration. These findings demonstrate that the optimization of assay duration via a ROC analysis can improve RT-QuIC assays for screening CWD in white-tailed deer.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Jiewen Guan
- Ottawa Laboratory Fallowfield, Canadian Food Inspection Agency, Ottawa, ON K2J 4S1, Canada
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2
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Vidal E, Sánchez-Martín MA, Eraña H, Lázaro SP, Pérez-Castro MA, Otero A, Charco JM, Marín B, López-Moreno R, Díaz-Domínguez CM, Geijo M, Ordóñez M, Cantero G, di Bari M, Lorenzo NL, Pirisinu L, d’Agostino C, Torres JM, Béringue V, Telling G, Badiola JJ, Pumarola M, Bolea R, Nonno R, Requena JR, Castilla J. Bona fide atypical scrapie faithfully reproduced for the first time in a rodent model. Acta Neuropathol Commun 2022; 10:179. [PMID: 36514160 PMCID: PMC9749341 DOI: 10.1186/s40478-022-01477-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 11/10/2022] [Indexed: 12/15/2022] Open
Abstract
Atypical Scrapie, which is not linked to epidemics, is assumed to be an idiopathic spontaneous prion disease in small ruminants. Therefore, its occurrence is unlikely to be controlled through selective breeding or other strategies as it is done for classical scrapie outbreaks. Its spontaneous nature and its sporadic incidence worldwide is reminiscent of the incidence of idiopathic spontaneous prion diseases in humans, which account for more than 85% of the cases in humans. Hence, developing animal models that consistently reproduce this phenomenon of spontaneous PrP misfolding, is of importance to study the pathobiology of idiopathic spontaneous prion disorders. Transgenic mice overexpressing sheep PrPC with I112 polymorphism (TgShI112, 1-2 × PrP levels compared to sheep brain) manifest clinical signs of a spongiform encephalopathy spontaneously as early as 380 days of age. The brains of these animals show the neuropathological hallmarks of prion disease and biochemical analyses of the misfolded prion protein show a ladder-like PrPres pattern with a predominant 7-10 kDa band. Brain homogenates from spontaneously diseased transgenic mice were inoculated in several models to assess their transmissibility and characterize the prion strain generated: TgShI112 (ovine I112 ARQ PrPC), Tg338 (ovine VRQ PrPC), Tg501 (ovine ARQ PrPC), Tg340 (human M129 PrPC), Tg361 (human V129 PrPC), TgVole (bank vole I109 PrPC), bank vole (I109I PrPC), and sheep (AHQ/ARR and AHQ/AHQ churra-tensina breeds). Our analysis of the results of these bioassays concludes that the strain generated in this model is indistinguishable to that causing atypical scrapie (Nor98). Thus, we present the first faithful model for a bona fide, transmissible, ovine, atypical scrapie prion disease.
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Affiliation(s)
- Enric Vidal
- grid.424716.2Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain ,grid.424716.2IRTA Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain
| | - Manuel A. Sánchez-Martín
- grid.11762.330000 0001 2180 1817Transgenic Facility. Department of Medicine, University of Salamanca, 37007 Salamanca, Spain
| | - Hasier Eraña
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain ,ATLAS Molecular Pharma S. L., Derio, Bizkaia Spain ,grid.413448.e0000 0000 9314 1427Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Sonia Pérez Lázaro
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Miguel A. Pérez-Castro
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain
| | - Alicia Otero
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Jorge M. Charco
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain ,ATLAS Molecular Pharma S. L., Derio, Bizkaia Spain ,grid.413448.e0000 0000 9314 1427Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain
| | - Belén Marín
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Rafael López-Moreno
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain
| | - Carlos M. Díaz-Domínguez
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain
| | - Mariví Geijo
- grid.509696.50000 0000 9853 6743Animal Health Department, NEIKER-Basque Institute for Agricultural Research and Development, Basque Research and Technology Alliance (BRTA), Derio, Spain
| | - Montserrat Ordóñez
- grid.424716.2Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain ,grid.424716.2IRTA Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain
| | - Guillermo Cantero
- grid.424716.2Unitat Mixta d’Investigació IRTA-UAB en Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain ,grid.424716.2IRTA Programa de Sanitat Animal, Centre de Recerca en Sanitat Animal (CReSA), Campus de la Universitat Autònoma de Barcelona (UAB), Bellaterra, Catalonia Spain
| | - Michele di Bari
- grid.416651.10000 0000 9120 6856Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161 Rome, Italy
| | - Nuria L. Lorenzo
- grid.11794.3a0000000109410645CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS, Santiago, Spain
| | - Laura Pirisinu
- grid.416651.10000 0000 9120 6856Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161 Rome, Italy
| | - Claudia d’Agostino
- grid.416651.10000 0000 9120 6856Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161 Rome, Italy
| | - Juan María Torres
- grid.419190.40000 0001 2300 669XCentro de Investigación en Sanidad Animal (CISA), Centro Superior de Investigaciones Científicas (CSIC) Valdeolmos, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), 28130 Madrid, Spain
| | - Vincent Béringue
- grid.417961.cMolecular Virology and Immunology, Institut National de La Recherche Agronomique (INRA), Université Paris-Saclay, Jouy-en-Josas, France
| | - Glenn Telling
- grid.47894.360000 0004 1936 8083Prion Research Center (PRC) and the Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO USA
| | - Juan J. Badiola
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Martí Pumarola
- Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Campus de UAB, Bellaterra, 08193 Barcelona, Catalonia Spain
| | - Rosa Bolea
- grid.11205.370000 0001 2152 8769Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza–IA2, Zaragoza, Spain
| | - Romolo Nonno
- grid.416651.10000 0000 9120 6856Department of Food Safety, Nutrition and Veterinary Public Health, Istituto Superiore Di Sanità, 00161 Rome, Italy
| | - Jesús R. Requena
- grid.11794.3a0000000109410645CIMUS Biomedical Research Institute, University of Santiago de Compostela-IDIS, Santiago, Spain
| | - Joaquín Castilla
- grid.420175.50000 0004 0639 2420Centro de Investigación Cooperativa en Biociencias (CIC BioGUNE), Laboratorio de Investigación de Priones, Basque Research and Technology Alliance (BRTA), Derio, Bizkaia Spain ,grid.413448.e0000 0000 9314 1427Centro de Investigación Biomédica en Red de Enfermedades Infecciosas (CIBERINFEC), Instituto de Salud Carlos III, Madrid, Spain ,grid.424810.b0000 0004 0467 2314IKERBASQUE, Basque Foundation for Science, Bilbao, Bizkaia Spain
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Koutsoumanis K, Allende A, Alvarez‐Ordóñez A, Bolton D, Bover‐Cid S, Chemaly M, Davies R, De Cesare A, Herman L, Lindqvist R, Nauta M, Peixe L, Ru G, Simmons M, Skandamis P, Suffredini E, Sánchez JÁ, Blagojevic B, Fürst P, Garin‐Bastuji B, Jensen HE, Paulsen P, Baert K, Barrucci F, Broglia A, Georgiadis M, Hempen M, Hilbert F. Evaluation of public and animal health risks in case of a delayed post-mortem inspection in ungulates. EFSA J 2020; 18:e06307. [PMID: 33304413 PMCID: PMC7716243 DOI: 10.2903/j.efsa.2020.6307] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
The potential effects of a 24 or 72-h delay in post-mortem inspection (PMI) of ungulates on public health and monitoring of animal health and welfare was evaluated. The assessment used a survey of meat inspectors, expert opinion, literature search and a stochastic model for Salmonella detection sensitivity. Disease detection sensitivity at a delayed PMI is expected to reduce detection sensitivity to a variable extent, depending on the hazard and on the signs/lesions and organs involved. No reduction is expected for Trichinella detection in meat from susceptible animal species and any decrease in detection of transmissible spongiform encephalopathies (TSEs) will not exceed the current tolerance for fallen stock. A 24-h delay in PMI could result in a small reduction in sensitivity of detection for tuberculosis, echinococcosis and cysticercosis. A greater reduction is expected for the detection of pyaemia and Rift valley fever. For the detection of Salmonella, the median model estimates are a reduction of sensitivity of 66.5% (90% probability interval (PI) 0.08-99.75%) after 24-h delay and 94% (90% PI 0.83-100%) after 72-h delay of PMI. Laboratory testing for tuberculosis following a sampling delay of 24-72 h could result in no, or a moderate, decrease in detection depending on the method of confirmation used (PCR, culture, histopathology). For chemical contaminants, a delay in meat inspection of 24 or 72 h is expected to have no impact on the effectiveness of detection of persistent organic pollutants and metals. However, for certain pharmacologically active substances, there will be a reduced effectiveness to detect some of these substances due to potential degradation in the available matrices (tissues and organs) and the non-availability of specific preferred matrices of choice.
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4
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Philiastides A, Ribes JM, Yip DCM, Schmidt C, Benilova I, Klöhn PC. A New Cell Model for Investigating Prion Strain Selection and Adaptation. Viruses 2019; 11:v11100888. [PMID: 31546723 PMCID: PMC6832381 DOI: 10.3390/v11100888] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 09/11/2019] [Indexed: 11/17/2022] Open
Abstract
Prion diseases are fatal neurodegenerative diseases that affect humans and animals. Prion strains, conformational variants of misfolded prion proteins, are associated with distinct clinical and pathological phenotypes. Host-strain interactions result in the selective damage of distinct brain areas and they are responsible for strain selection and/or adaptation, but the underlying molecular mechanisms are unknown. Prion strains can be distinguished by their cell tropism in vivo and in vitro, which suggests that susceptibility to distinct prion strains is determined by cellular factors. The neuroblastoma cell line PK1 is refractory to the prion strain Me7, but highly susceptible to RML. We challenged a large number of clonal PK1 lines with Me7 and successfully selected highly Me7-susceptible subclones (PME) to investigate whether the prion strain repertoire of PK1 can be expanded. Notably, the Me7-infected PME clones were more protease-resistant when compared to RML-infected PME clones, which suggested that cell-adapted Me7 and RML are distinct prion strains. Strikingly, Me7-refractory cells, including PK1 and astrocytes in cortico-hippocampal cultures, are highly susceptible to prions, being derived from homogenates of Me7-infected PME cells, suggesting that the passage of Me7 in PME cells leads to an extended host range. Thus, PME clones represent a compelling cell model for strain selection and adaptation.
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Affiliation(s)
- Alexandra Philiastides
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London W1W7FF, UK.
| | - Juan Manuel Ribes
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London W1W7FF, UK.
| | - Daniel Chun-Mun Yip
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London W1W7FF, UK.
| | - Christian Schmidt
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London W1W7FF, UK.
| | - Iryna Benilova
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London W1W7FF, UK.
| | - Peter-Christian Klöhn
- MRC Prion Unit at UCL, UCL Institute of Prion Diseases, 33 Cleveland Street, London W1W7FF, UK.
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5
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Spiropoulos J, Lockey R, Beck KE, Vickery C, Holder TM, Thorne L, Arnold M, Andreoletti O, Simmons MM, Terry LA. Incomplete inactivation of atypical scrapie following recommended autoclave decontamination procedures. Transbound Emerg Dis 2019; 66:1993-2001. [PMID: 31111687 DOI: 10.1111/tbed.13247] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 03/21/2019] [Accepted: 05/16/2019] [Indexed: 11/28/2022]
Abstract
Prions are highly resistant to the decontamination procedures normally used to inactivate conventional pathogens. This is a challenging problem not only in the medical and veterinary fields for minimizing the risk of transmission from potentially infective sources but also for ensuring the safe disposal or subsequent use of animal by-products. Specific pressure autoclaving protocols were developed for this purpose, but different strains of prions have been reported to have differing resistance patterns to established prion decontamination procedures, and as additional TSE strains are identified it is necessary to determine the effectiveness of such procedures. In this study we assessed the efficacy of sterilization using the EU recommended autoclave procedure for prions (133°C, 3 Bar for 20 min) on the atypical or Nor98 (AS/Nor98) scrapie strain of sheep and goats. Using a highly sensitive murine mouse model (tg338) that overexpresses ovine PrPC , we determined that this method of decontamination reduced the infectivity titre by 1010 . Infectivity was nonetheless still detected after applying the recommended autoclaving protocol. This shows that AS/Nor98 can survive the designated legislative decontamination conditions, albeit with a significant decrease in titre. The infectivity of a classical scrapie isolate subjected to the same decontamination conditions was reduced by 106 suggesting that the AS/Nor98 isolate is less sensitive to decontamination than the classical scrapie source.
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Affiliation(s)
| | - Richard Lockey
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Katy E Beck
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Chris Vickery
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Thomas M Holder
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Leigh Thorne
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Mark Arnold
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
| | - Olivier Andreoletti
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | | | - Linda A Terry
- Animal and Plant Health Agency (APHA), Weybridge, Surrey, UK
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6
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Jeffrey M, González L, Simmons MM, Hunter N, Martin S, McGovern G. Altered trafficking of abnormal prion protein in atypical scrapie: prion protein accumulation in oligodendroglial inner mesaxons. Neuropathol Appl Neurobiol 2017; 43:215-226. [PMID: 26750308 DOI: 10.1111/nan.12302] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 01/04/2016] [Accepted: 01/10/2016] [Indexed: 01/09/2023]
Abstract
AIMS Prion diseases exist in classical and atypical disease forms. Both forms are characterized by disease-associated accumulation of a host membrane sialoglycoprotein known as prion protein (PrPd ). In classical forms of prion diseases, PrPd can accumulate in the extracellular space as fibrillar amyloid, intracellularly within lysosomes, but mainly on membranes in association with unique and characteristic membrane pathology. These membrane changes are found in all species and strains of classical prion diseases and consist of spiral, branched and clathrin-coated membrane invaginations on dendrites. Atypical prion diseases have been described in ruminants and man and have distinct biological, biochemical and pathological properties when compared to classical disease. The purpose of this study was to determine whether the subcellular pattern of PrPd accumulation and membrane changes in atypical scrapie were the same as those found in classical prion diseases. METHODS Immunogold electron microscopy was used to examine brains of atypical scrapie-affected sheep and Tg338 mice. RESULTS Classical prion disease-associated membrane lesions were not found in atypical scrapie-affected sheep, however, white matter PrPd accumulation was localized mainly to the inner mesaxon and paranodal cytoplasm of oligodendroglia. Similar lesions were found in myelinated axons of atypical scrapie Tg338-infected mice. However, Tg338 mice also showed the unique grey matter membrane changes seen in classical forms of disease. CONCLUSIONS These data show that atypical scrapie infection directs a change in trafficking of abnormal PrP to axons and oligodendroglia and that the resulting pathology is an interaction between the agent strain and host genotype.
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Affiliation(s)
- M Jeffrey
- Pathology Department, Animal and Plant Health Agency, Lasswade, UK
| | - L González
- Pathology Department, Animal and Plant Health Agency, Lasswade, UK
| | - M M Simmons
- Pathology Department, Animal and Plant Health Agency, Addlestone, UK
| | - N Hunter
- The Roslin Institute, University of Edinburgh, Midlothian, UK
| | - S Martin
- Pathology Department, Animal and Plant Health Agency, Lasswade, UK
| | - G McGovern
- Pathology Department, Animal and Plant Health Agency, Lasswade, UK
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7
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Imamura M, Miyazawa K, Iwamaru Y, Matsuura Y, Yokoyama T, Okada H. Identification of the first case of atypical scrapie in Japan. J Vet Med Sci 2016; 78:1915-1919. [PMID: 27616556 PMCID: PMC5240776 DOI: 10.1292/jvms.16-0379] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
A Corriedale ewe was confirmed as the first atypical scrapie case during an active surveillance program for transmissible spongiform encephalopathies in small ruminants in Japan. The animal was homozygous for the AF141RQ haplotype of PRNP. The animal showed clinical neurological signs possibly due to listeriosis before culling. Western blot analysis showed an unusual multiple banded pattern with a low-molecular fragment at ~7 kDa. Histopathology revealed suppurative meningoencephalitis caused by listeriosis in the brainstem. Fine granular to globular immunostaining of disease-associated prion proteins was mainly detected in the neuropil of the spinal tract of the trigeminal nerve and in the white matter of the spinocerebellar tract. Based on these results, this case was conclusively diagnosed as atypical scrapie with encephalitic listeriosis.
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Affiliation(s)
- Morikazu Imamura
- National Institute of Animal Health, National Agriculture and Food Research Organization (NARO), Tsukuba, Ibaraki 305-0856, Japan
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8
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Konold T, Phelan LJ, Cawthraw S, Simmons MM, Chaplin MJ, González L. Abnormalities in Brainstem Auditory Evoked Potentials in Sheep with Transmissible Spongiform Encephalopathies and Lack of a Clear Pathological Relationship. Front Vet Sci 2016; 3:60. [PMID: 27532040 PMCID: PMC4969942 DOI: 10.3389/fvets.2016.00060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/14/2016] [Indexed: 11/13/2022] Open
Abstract
Scrapie is transmissible spongiform encephalopathy (TSE), which causes neurological signs in sheep, but confirmatory diagnosis is usually made postmortem on examination of the brain for TSE-associated markers like vacuolar changes and disease-associated prion protein (PrP(Sc)). The objective of this study was to evaluate whether testing of brainstem auditory evoked potentials (BAEPs) at two different sound levels could aid in the clinical diagnosis of TSEs in sheep naturally or experimentally infected with different TSE strains [classical and atypical scrapie and bovine spongiform encephalopathy (BSE)] and whether any BAEP abnormalities were associated with TSE-associated markers in the auditory pathways. BAEPs were recorded from 141 clinically healthy sheep of different breeds and ages that tested negative for TSEs on postmortem tests to establish a reference range and to allow comparison with 30 sheep clinically affected or exposed to classical scrapie (CS) without disease confirmation (test group 1) and 182 clinically affected sheep with disease confirmation (test group 2). Abnormal BAEPs were found in 7 sheep (23%) of group 1 and 42 sheep (23%) of group 2. The proportion of sheep with abnormalities did not appear to be influenced by TSE strain or PrP(Sc) gene polymorphisms. When the magnitude of TSE-associated markers in the auditory pathways was compared between a subset of 12 sheep with and 12 sheep without BAEP abnormalities in group 2, no significant differences in the total PrP(Sc) or vacuolation scores in the auditory pathways could be found. However, the data suggested that there was a difference in the PrP(Sc) scores depending on the TSE strain because PrP(Sc) scores were significantly higher in sheep with BAEP abnormalities infected with classical and L-type BSE, but not with CS. The results indicated that BAEPs may be abnormal in sheep infected with TSEs but the test is not specific for TSEs and that neither vacuolation nor PrP(Sc) accumulation appears to be responsible for the clinical abnormalities.
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Affiliation(s)
- Timm Konold
- Animal Sciences Unit, Animal and Plant Health Agency, Weybridge, Addlestone, UK
| | - Laura J. Phelan
- Animal Sciences Unit, Animal and Plant Health Agency, Weybridge, Addlestone, UK
| | - Saira Cawthraw
- Central Sequencing Unit, Animal and Plant Health Agency, Weybridge, Addlestone, UK
| | - Marion M. Simmons
- Pathology Department, Animal and Plant Health Agency, Weybridge, Addlestone, UK
| | - Melanie J. Chaplin
- Pathology Department, Animal and Plant Health Agency, Weybridge, Addlestone, UK
| | - Lorenzo González
- Pathology Department, Animal and Plant Health Agency, Lasswade, Penicuik, UK
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9
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Methods for Differentiating Prion Types in Food-Producing Animals. BIOLOGY 2015; 4:785-813. [PMID: 26580664 PMCID: PMC4690018 DOI: 10.3390/biology4040785] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Revised: 10/29/2015] [Accepted: 11/04/2015] [Indexed: 12/05/2022]
Abstract
Prions are an enigma amongst infectious disease agents as they lack a genome yet confer specific pathologies thought to be dictated mainly, if not solely, by the conformation of the disease form of the prion protein (PrPSc). Prion diseases affect humans and animals, the latter including the food-producing ruminant species cattle, sheep, goats and deer. Importantly, it has been shown that the disease agent of bovine spongiform encephalopathy (BSE) is zoonotic, causing variant Creutzfeldt Jakob disease (vCJD) in humans. Current diagnostic tests can distinguish different prion types and in food-producing animals these focus on the differentiation of BSE from the non-zoonotic agents. Whilst BSE cases are now rare, atypical forms of both scrapie and BSE have been reported, as well as two types of chronic wasting disease (CWD) in cervids. Typing of animal prion isolates remains an important aspect of prion diagnosis and is now becoming more focused on identifying the range of prion types that are present in food-producing animals and also developing tests that can screen for emerging, novel prion diseases. Here, we review prion typing methodologies in light of current and emerging prion types in food-producing animals.
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10
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Soutyrine A, Yogasingam N, Huang H, Mitchell G. Effects of heme-PrP complex on cell-free conversion and peroxidase-linked immunodetection of prions in blood-based assays. Res Vet Sci 2015; 101:168-74. [PMID: 26022071 DOI: 10.1016/j.rvsc.2015.05.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Revised: 05/08/2015] [Accepted: 05/13/2015] [Indexed: 01/02/2023]
Abstract
Prion protein (PrP) binding to natural and synthetic porphyrins has been previously demonstrated but the effects of endogenous heme interactions with PrP remain uncertain. This study investigated implications of this interaction in blood-based peroxidase-linked prion immunodetection and seeded conversion of cellular prion (PrP(C)) into disease associated form (PrP(Sc)). Heme binding to recombinant PrP(C) enhanced intrinsic peroxidase activity (POD) by 2.5-fold and POD inherent to denatured blood accounted for over 84% of luminol-based substrate oxidation in a prion immunodetection assay. An immuno-capture assay showed that 75-98% of blood POD was attributable to binding of PrP(C) with endogenous heme. Additionally, 10 μM heme inhibited (P<0.05) the seeded conversion of PrP(C) to PrP(Sc) through the protein misfolding cycling amplification assay. We conclude that the observed effects can interfere with cell-free conversion and peroxidase-linked immunodetection of prions in blood-based assays. These results indicate that heme-PrP interactions could modulate intrinsic POD and protect PrP(C) from conversion into PrP(Sc).
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Affiliation(s)
- Andrei Soutyrine
- Ottawa Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada.
| | - Nishandan Yogasingam
- Ottawa Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Hongsheng Huang
- Ottawa Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
| | - Gordon Mitchell
- Ottawa Laboratory (Fallowfield), Canadian Food Inspection Agency, Ottawa, Ontario, Canada
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11
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Gielbert A, Thorne JK, Hope J. Pyroglutamyl-N-terminal prion protein fragments in sheep brain following the development of transmissible spongiform encephalopathies. Front Mol Biosci 2015; 2:7. [PMID: 25988175 PMCID: PMC4429639 DOI: 10.3389/fmolb.2015.00007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 02/17/2015] [Indexed: 12/20/2022] Open
Abstract
Protein misfolding, protein aggregation and disruption to cellular proteostasis are key processes in the propagation of disease and, in some progressive neurodegenerative diseases of the central nervous system, the misfolded protein can act as a self-replicating template or prion converting its normal isoform into a misfolded copy of itself. We have investigated the sheep transmissible spongiform encephalopathy, scrapie, and developed a multiple selected reaction monitoring (mSRM) mass spectrometry assay to quantify brain peptides representing the “ragged” N-terminus and the core of ovine prion protein (PrPSc) by using Q-Tof mass spectrometry. This allowed us to identify pyroglutamylated N-terminal fragments of PrPSc at residues 86, 95 and 101, and establish that these fragments were likely to be the result of in vivo processes. We found that the ratios of pyroglutamylated PrPSc fragments were different in sheep of different breeds and geographical origin, and our expanded ovine PrPSc assay was able to determine the ratio and allotypes of PrP accumulating in diseased brain of PrP heterozygous sheep; it also revealed significant differences between N-terminal amino acid profiles (N-TAAPs) in other types of ovine prion disease, CH1641 scrapie and ovine BSE. Variable rates of PrP misfolding, aggregation and degradation are the likely basis for phenotypic (or strain) differences in prion-affected animals and our mass spectrometry-based approach allows the simultaneous investigation of factors such as post-translational modification (pyroglutamyl formation), conformation (by N-TAAP analysis) and amino-acid polymorphisms (allotype ratio) which affect the kinetics of these proteostatic processes.
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Affiliation(s)
- Adriana Gielbert
- Department of Pathology, Animal and Plant Health Agency-Weybridge Addlestone, UK
| | - Jemma K Thorne
- Department of Pathology, Animal and Plant Health Agency-Weybridge Addlestone, UK
| | - James Hope
- Science Strategy Group, Animal and Plant Health Agency-Weybridge Addlestone, UK
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12
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Highly sensitive detection of small ruminant bovine spongiform encephalopathy within transmissible spongiform encephalopathy mixes by serial protein misfolding cyclic amplification. J Clin Microbiol 2014; 52:3863-8. [PMID: 25143565 DOI: 10.1128/jcm.01693-14] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It is assumed that sheep and goats consumed the same bovine spongiform encephalopathy (BSE)-contaminated meat and bone meal that was fed to cattle and precipitated the BSE epidemic in the United Kingdom that peaked more than 20 years ago. Despite intensive surveillance for cases of BSE within the small ruminant populations of the United Kingdom and European Union, no instances of BSE have been detected in sheep, and in only two instances has BSE been discovered in goats. If BSE is present within the small ruminant populations, it may be at subclinical levels, may manifest as scrapie, or may be masked by coinfection with scrapie. To determine whether BSE is potentially circulating at low levels within the European small ruminant populations, highly sensitive assays that can specifically detect BSE, even within the presence of scrapie prion protein, are required. Here, we present a novel assay based on the specific amplification of BSE PrP(Sc) using the serial protein misfolding cyclic amplification assay (sPMCA), which specifically amplified small amounts of ovine and caprine BSE agent which had been mixed into a range of scrapie-positive brain homogenates. We detected the BSE prion protein within a large excess of classical, atypical, and CH1641 scrapie isolates. In a blind trial, this sPMCA-based assay specifically amplified BSE PrP(Sc) within brain mixes with 100% specificity and 97% sensitivity when BSE agent was diluted into scrapie-infected brain homogenates at 1% (vol/vol).
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13
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Doss CGP, Rajith B, Rajasekaran R, Srajan J, Nagasundaram N, Debajyoti C. In silico analysis of prion protein mutants: a comparative study by molecular dynamics approach. Cell Biochem Biophys 2014; 67:1307-18. [PMID: 23723004 DOI: 10.1007/s12013-013-9663-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Polymorphisms in the human prion proteins lead to amino acid substitutions by the conversion of PrPC to PrPSc and amyloid formation, resulting in prion diseases such as familial Creutzfeldt-Jakob disease, Gerstmann-Straussler-Scheinker disease and fatal familial insomnia. Cation-π interaction is a non-covalent binding force that plays a significant role in protein stability. Here, we employ a novel approach by combining various in silico tools along with molecular dynamics simulation to provide structural and functional insight into the effect of mutation on the stability and activity of mutant prion proteins. We have investigated impressions of prevalent mutations including 1E1S, 1E1P, 1E1U, 1E1P, 1FKC and 2K1D on the human prion proteins and compared them with wild type. Structural analyses of the models were performed with the aid of molecular dynamics simulation methods. According to our results, frequently occurred mutations were observed in conserved sequences of human prion proteins and the most fluctuation values appear in the 2K1D mutant model at around helix 4 with residues ranging from 190 to 194. Our observations in this study could help to further understand the structural stability of prion proteins.
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Affiliation(s)
- C George Priya Doss
- Medical Biotechnology Division, School of Biosciences and Technology, VIT University, Vellore, 632014, Tamil Nadu, India,
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Konold T, Phelan L. Clinical examination protocol for the detection of scrapie. Vet Rec 2014; 174:257. [DOI: 10.1136/vr.g1971] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Timm Konold
- AHVLA - Weybridge; New Haw Addlestone Surrey KT15 3NB
| | - Laura Phelan
- AHVLA - Weybridge; New Haw Addlestone Surrey KT15 3NB
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15
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Pirisinu L, Nonno R, Esposito E, Benestad SL, Gambetti P, Agrimi U, Zou WQ. Small ruminant nor98 prions share biochemical features with human gerstmann-sträussler-scheinker disease and variably protease-sensitive prionopathy. PLoS One 2013; 8:e66405. [PMID: 23826096 PMCID: PMC3691246 DOI: 10.1371/journal.pone.0066405] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Accepted: 05/06/2013] [Indexed: 01/08/2023] Open
Abstract
Prion diseases are classically characterized by the accumulation of pathological prion protein (PrPSc) with the protease resistant C-terminal fragment (PrPres) of 27–30 kDa. However, in both humans and animals, prion diseases with atypical biochemical features, characterized by PK-resistant PrP internal fragments (PrPres) cleaved at both the N and C termini, have been described. In this study we performed a detailed comparison of the biochemical features of PrPSc from atypical prion diseases including human Gerstmann-Sträussler-Scheinker disease (GSS) and variably protease-sensitive prionopathy (VPSPr) and in small ruminant Nor98 or atypical scrapie. The kinetics of PrPres production and its cleavage sites after PK digestion were analyzed, along with the PrPSc conformational stability, using a new method able to characterize both protease-resistant and protease-sensitive PrPSc components. All these PrPSc types shared common and distinctive biochemical features compared to PrPSc from classical prion diseases such as sporadic Creutzfeldt-Jakob disease and scrapie. Notwithstanding, distinct biochemical signatures based on PrPres cleavage sites and PrPSc conformational stability were identified in GSS A117V, GSS F198S, GSS P102L and VPSPr, which allowed their specific identification. Importantly, the biochemical properties of PrPSc from Nor98 and GSS P102L largely overlapped, but were distinct from the other human prions investigated. Finally, our study paves the way towards more refined comparative approaches to the characterization of prions at the animal–human interface.
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Affiliation(s)
- Laura Pirisinu
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
- * E-mail: (LP); (WQZ)
| | - Romolo Nonno
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Elena Esposito
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | | | - Pierluigi Gambetti
- Department of Pathology, National Prion Disease Pathology Surveillance Center, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
| | - Umberto Agrimi
- Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy
| | - Wen-Quan Zou
- Department of Pathology, National Prion Disease Pathology Surveillance Center, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
- * E-mail: (LP); (WQZ)
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16
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Konold T, Moore SJ, Bellworthy SJ, Terry LA, Thorne L, Ramsay A, Salguero FJ, Simmons MM, Simmons HA. Evidence of effective scrapie transmission via colostrum and milk in sheep. BMC Vet Res 2013; 9:99. [PMID: 23651710 PMCID: PMC3750761 DOI: 10.1186/1746-6148-9-99] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Accepted: 04/30/2013] [Indexed: 11/30/2022] Open
Abstract
Background Evidence for scrapie transmission from VRQ/VRQ ewes to lambs via milk was first reported in 2008 but in that study there were concerns that lateral transmission may have contributed to the high transmission rate observed since five control lambs housed with the milk recipients also became infected. This report provides further information obtained from two follow-up studies, one where milk recipients were housed separately after milk consumption to confirm the validity of the high scrapie transmission rate via milk and the second to assess any difference in infectivity from colostrum and subsequent milk. Protein misfolding cyclic amplification (PMCA) was also used to detect prion protein in milk samples as a comparison with the infectivity data and extended to milk samples from ewes without a VRQ allele. Results Seven pairs of lambs fed colostrum and milk individually from seven scrapie-affected sheep (pre-clinical or clinical) presented with disease-associated prion protein, PrPd, in rectal lymphoid tissue at 4–5 months of age. Five further pairs of lambs fed either colostrum or subsequent milk from five pre-clinical scrapie-affected sheep equally presented with PrPd in lymphoid tissue by 9 months of age. Nine sheep were lost due to intercurrent diseases but all remaining milk or colostrum recipients, including those in the original study with the lateral transmission controls, developed clinical signs of scrapie from 19 months of age and scrapie was confirmed by brain examination. Unexposed control sheep totalling 19 across all three studies showed no evidence of infection. Scrapie PrP was amplified repeatedly by PMCA in all tested milk samples from scrapie-affected VRQ/VRQ sheep, and in one scrapie-affected ARQ/ARQ sheep. By contrast, milk samples from five VRQ/VRQ and 11 ARQ/ARQ scrapie-free sheep did not have detectable scrapie PrP on repeated tests. Conclusions Feeding of milk from scrapie-affected sheep results in a high transmission rate in VRQ/VRQ sheep and both colostrum and milk transmit scrapie. Detection of scrapie prion protein in individual milk samples from scrapie-affected ewes confirms PMCA as a valuable in vitro test.
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Affiliation(s)
- Timm Konold
- Specialist Scientific Support Department, Animal Health and Veterinary Laboratories Agency Weybridge, New Haw Addlestone, Surrey KT15 3NB, UK.
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17
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Meydan H, Özkan MM, Yildiz MA. Genetic risk assessment for atypical scrapie in Turkish native sheep breeds. Small Rumin Res 2013. [DOI: 10.1016/j.smallrumres.2012.08.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Taema MM, Maddison BC, Thorne L, Bishop K, Owen J, Hunter N, Baker CA, Terry LA, Gough KC. Differentiating ovine BSE from CH1641 scrapie by serial protein misfolding cyclic amplification. Mol Biotechnol 2012; 51:233-9. [PMID: 21987099 DOI: 10.1007/s12033-011-9460-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Whilst ovine BSE displays distinct pathological characteristics to ovine CH1641-like scrapie upon passage in rodents, they have very similar molecular phenotypes. As such, the in vitro differentiation of these strains in routine surveillance programmes presents a significant diagnostic challenge. In this study, using serial protein-misfolding cyclic amplification (sPMCA), ovine BSE was readily amplified in vitro in brain substrates from sheep with V₁₃₆R₁₅₄Q₁₇₁/V₁₃₆R₁₅₄Q₁₇₁ or AHQ/AHQ PRNP genotypes. In contrast, the CH1641 strain was refractory to such amplification. This method allowed for complete and unequivocal differentiation of experimental BSE from CH1641 prion strains within an ovine host.
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Affiliation(s)
- Maged M Taema
- School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington Campus, College Road, Sutton Bonington, Leicestershire LE12 5RD, UK
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19
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All major prion types recognised by a multiplex immunofluorometric assay for disease screening and confirmation in sheep. J Immunol Methods 2012; 380:30-9. [PMID: 22498749 DOI: 10.1016/j.jim.2012.03.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 03/14/2012] [Accepted: 03/21/2012] [Indexed: 01/11/2023]
Abstract
Prion diseases or transmissible spongiform encephalopathies (TSEs) in small ruminants are presented in many forms: classical scrapie, Nor98/atypical scrapie, CH1641 scrapie and bovine spongiform encephalopathy (BSE). We previously described a multiplex immunofluorometric assay (mIFMA), based on a bead array flow cytometry technology, which provided, in a single assay, discrimination between BSE (in cattle and sheep) and classical scrapie (Tang et al., 2010). In this study, we extended the mlFMA to differentiate classical scrapie, atypical scrapie, BSE (experimentally infected sheep and naturally infected cattle) and CH1641 (both experimental and natural CH1641-like infections in sheep). Three capture antibodies were used, two distinct PrP N-terminus specific antibodies 12B2 and 9A2, and a PrP core specific antibody 94B4. All three antibodies were shown to bind classical scrapie PrP(res) strongly, whereas in Nor98/atypical scrapie PrP(res) only 12B2 and 9A2 binding was observed. PrP(res) binding of 12B2 was low for both BSE and CH1641, as expected. Furthermore, analysis of serially diluted samples indicated that the assay provided a similar level of sensitivity for atypical scrapie as that found using a well established commercial test. Unexpectedly, 9A2 binding to CH1641 PrP(res) was reduced by 2.1 fold both for experimental CH1641 and CH1641-like scrapie when compared with BSE, suggesting that major cleavage of the N-terminus occurs further towards the C-terminus in CH1641 than in BSE. The ratios of 12B2/94B4 and 9A2/94B4 were similar between experimental CH1641 and CH1641-like cases, although two CH1641-like subjects displayed slightly elevated ratios of both 12B2/94B4 and 9A2/94B4. To verify this finding for PrP(res), mass spectrometry based quantification was used to determine the absolute abundance of the peptides associated with all three antibody binding regions. There was a 2.2 fold reduction of peptides containing the 9A2 epitope for experimental CH1641 PrP(res) in comparison to BSE PrP(res). Observation of reduced PrP(res) may serve as a new marker for CH1641. This mIFMA may thus provide the basis for simplified TSE diagnosis with capability for simultaneous screening and differential diagnosis.
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20
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Breyer J, Wemheuer WM, Wrede A, Graham C, Benestad SL, Brenig B, Richt JA, Schulz-Schaeffer WJ. Detergents modify proteinase K resistance of PrP Sc in different transmissible spongiform encephalopathies (TSEs). Vet Microbiol 2011; 157:23-31. [PMID: 22226540 DOI: 10.1016/j.vetmic.2011.12.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Revised: 11/16/2011] [Accepted: 12/08/2011] [Indexed: 10/14/2022]
Abstract
Prion diseases are diagnosed by the detection of their proteinase K-resistant prion protein fragment (PrP(Sc)). Various biochemical protocols use different detergents for the tissue preparation. We found that the resistance of PrP(Sc) against proteinase K may vary strongly with the detergent used. In our study, we investigated the influence of the most commonly used detergents on eight different TSE agents derived from different species and distinct prion disease forms. For a high throughput we used a membrane adsorption assay to detect small amounts of prion aggregates, as well as Western blotting. Tissue lysates were prepared using DOC, SLS, SDS or Triton X-100 in different concentrations and these were digested with various amounts of proteinase K. Detergents are able to enhance or diminish the detectability of PrP(Sc) after proteinase K digestion. Depending on the kind of detergent, its concentration - but also on the host species that developed the TSE and the disease form or prion type - the detectability of PrP(Sc) can be very different. The results obtained here may be helpful during the development or improvement of a PrP(Sc) detection method and they point towards a detergent effect that can be additionally used for decontamination purposes. A plausible explanation for the detergent effects described in this article could be an interaction with the lipids associated with PrP(Sc) that may stabilize the aggregates.
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Affiliation(s)
- Johanna Breyer
- Prion and Dementia Research Unit, Department of Neuropathology, University Medical Center Göttingen, Robert Koch Str. 40, 37075 Göttingen, Germany
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21
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Götte DR, Benestad SL, Laude H, Zurbriggen A, Oevermann A, Seuberlich T. Atypical scrapie isolates involve a uniform prion species with a complex molecular signature. PLoS One 2011; 6:e27510. [PMID: 22096587 PMCID: PMC3214077 DOI: 10.1371/journal.pone.0027510] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Accepted: 10/18/2011] [Indexed: 12/20/2022] Open
Abstract
The pathobiology of atypical scrapie, a prion disease affecting sheep and goats, is still poorly understood. In a previous study, we demonstrated that atypical scrapie affecting small ruminants in Switzerland differs in the neuroanatomical distribution of the pathological prion protein (PrPd). To investigate whether these differences depend on host-related vs. pathogen-related factors, we transmitted atypical scrapie to transgenic mice over-expressing the ovine prion protein (tg338). The clinical, neuropathological, and molecular phenotype of tg338 mice is similar between mice carrying the Swiss atypical scrapie isolates and the Nor98, an atypical scrapie isolate from Norway. Together with published data, our results suggest that atypical scrapie is caused by a uniform type of prion, and that the observed phenotypic differences in small ruminants are likely host-dependant. Strikingly, by using a refined SDS-PAGE technique, we established that the prominent proteinase K-resistant prion protein fragment in atypical scrapie consists of two separate, unglycosylated peptides with molecular masses of roughly 5 and 8 kDa. These findings show similarities to those for other prion diseases in animals and humans, and lay the groundwork for future comparative research.
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Affiliation(s)
- Dorothea R. Götte
- NeuroCentre, National and OIE Reference Laboratories for BSE and Scrapie, Division of Experimental Clinical Research, Vetsuisse Faculty, University of Berne, Berne, Switzerland
| | | | - Hubert Laude
- 3U892 Virologie Immunologie Moléculaires, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
| | - Andreas Zurbriggen
- NeuroCentre, National and OIE Reference Laboratories for BSE and Scrapie, Division of Experimental Clinical Research, Vetsuisse Faculty, University of Berne, Berne, Switzerland
| | - Anna Oevermann
- NeuroCentre, National and OIE Reference Laboratories for BSE and Scrapie, Division of Experimental Clinical Research, Vetsuisse Faculty, University of Berne, Berne, Switzerland
| | - Torsten Seuberlich
- NeuroCentre, National and OIE Reference Laboratories for BSE and Scrapie, Division of Experimental Clinical Research, Vetsuisse Faculty, University of Berne, Berne, Switzerland
- * E-mail:
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22
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Perrott MR, Sigurdson CJ, Mason GL, Hoover EA. Evidence for distinct chronic wasting disease (CWD) strains in experimental CWD in ferrets. J Gen Virol 2011; 93:212-221. [PMID: 21918005 DOI: 10.1099/vir.0.035006-0] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Chronic wasting disease (CWD) is an evolving prion disease of cervids (deer, elk and moose) that has been recognized in North America and Korea. Infection of non-cervid reservoir or transport species in nature is not reported. However, the ferret (Mustela putorius furo) is susceptible to CWD after experimental inoculation. Here, we report that infection of ferrets with either of two ferret CWD isolates by various routes of exposure has revealed biologically distinct strain-like properties distinguished by different clinical progression and survival period. The isolates of ferret CWD were also differentiated by the distribution of the infectious prion protein (PrP(CWD)) in the brain and periphery, and by the proteinase K sensitivity of PrP(CWD). These findings suggest that diversity in prion conformers exists in CWD-infected cervids.
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Affiliation(s)
- Matthew R Perrott
- Institute of Veterinary, Animal and Biomedical Sciences, Massey University, Palmerston North 4442, New Zealand
| | - Christina J Sigurdson
- Dept Pathology, University of California, San Diego, 9500 Gilman Dr., La Jolla, CA 92093, USA
| | - Gary L Mason
- Dept Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | - Edward A Hoover
- Dept Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA
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23
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Kittelberger R, Chaplin MJ, Simmons MM, Ramirez-Villaescusa A, McIntyre L, MacDiarmid SC, Hannah MJ, Jenner J, Bueno R, Bayliss D, Black H, Pigott CJ, O'Keefe JS. Atypical scrapie/Nor98 in a sheep from New Zealand. J Vet Diagn Invest 2011; 22:863-75. [PMID: 21088169 DOI: 10.1177/104063871002200604] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
In a consignment of sheep brains from New Zealand, to be used in Europe as negative control material in scrapie rapid screening test evaluations, brain samples from 1 sheep (no. 1512) gave the following initially confusing results in various screening tests: the brainstem repeatedly produced negative results in 2 very similar screening kits (enzyme-linked immunosorbent assay [ELISA]-1, ELISA-2), a macerate made from brainstem and cerebellum returned a clearly positive result in ELISA-2, and the macerate and a brainstem sample gave negative results in a third screening test (ELISA-3). In subsequent testing, cerebellum tissue alone tested strongly positive in ELISA-1 and produced a banding pattern very similar to atypical scrapie/Nor98 in a confirmatory Western blot (WB). The macerate showed weak staining in the confirmatory WB but presented a staining pattern identical to atypical scrapie/Nor98 in the scrapie-associated fibril WB. The latter test confirmed conclusively the first case of atypical scrapie/Nor98 in a sheep from New Zealand. Other parts of the brain either tested negative or very weak positive in ELISA-2 and in WBs, or tested with negative results by histopathology and immunohistochemistry. It appears that sheep no. 1512 is a case of atypical scrapie/Nor98 in which the abnormal prion protein was detected mainly in the cerebellum. This case emphasizes the need to retain brainstem, and cerebral and cerebellar tissues, as frozen and fixed materials, for conclusive confirmatory testing. Furthermore, consideration should be given to which screening method to use.
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Affiliation(s)
- Reinhold Kittelberger
- Investigation and Diagnostic Centre Wallaceville, Biosecurity New Zealand, Ministry of Agriculture and Forestry, PO Box 40742, Upper Hutt 5140, New Zealand.
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24
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Seuberlich T, Heim D, Zurbriggen A. Atypical transmissible spongiform encephalopathies in ruminants: a challenge for disease surveillance and control. J Vet Diagn Invest 2011; 22:823-42. [PMID: 21088166 DOI: 10.1177/104063871002200601] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Since 1987, when bovine spongiform encephalopathy (BSE) emerged as a novel disease in cattle, enormous efforts were undertaken to monitor and control the disease in ruminants worldwide. The driving force was its high economic impact, which resulted from trade restrictions and the loss of consumer confidence in beef products, the latter because BSE turned out to be a fatal zoonosis, causing variant Creutzfeldt-Jakob disease in human beings. The ban on meat and bone meal in livestock feed and the removal of specified risk materials from the food chain were the main measures to successfully prevent infection in cattle and to protect human beings from BSE exposure. However, although BSE is now under control, previously unknown, so-called atypical transmissible spongiform encephalopathies (TSEs) in cattle and small ruminants have been identified by enhanced disease surveillance. This report briefly reviews and summarizes the current level of knowledge on the spectrum of TSEs in cattle and small ruminants and addresses the question of the extent to which such atypical TSEs have an effect on disease surveillance and control strategies.
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Affiliation(s)
- Torsten Seuberlich
- NeuroCentre, National and OIE Reference Laboratories for BSE and Scrapie, DCR-VPH, Bremgartenstrasse 109a, CH-3001 Berne, Switzerland.
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Marie McIntyre K, Del Rio Vilas VJ, Gubbins S. Demographic characteristics of scrapie-affected holdings identified by active and passive surveillance schemes in Great Britain: 2002–2005. Vet J 2011; 187:207-11. [DOI: 10.1016/j.tvjl.2009.12.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2008] [Revised: 11/18/2009] [Accepted: 12/05/2009] [Indexed: 10/20/2022]
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26
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Joint Scientific Opinion on any possible epidemiological or molecular association between TSEs in animals and humans. EFSA J 2011. [DOI: 10.2903/j.efsa.2011.1945] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
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27
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Abstract
Here we review the known strain profiles of various prion diseases of animals and humans, and how transgenic mouse models are being used to elucidate basic molecular mechanisms of prion propagation and strain variation and for assessing the zoonotic potential of various animal prion strains.
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Affiliation(s)
- Glenn C Telling
- Sanders Brown Center on Aging, University of Kentucky Medical Center, Lexington, KY 40506, USA.
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28
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Abstract
Although prion diseases, such as Creutzfeldt-Jakob disease (CJD) in humans and scrapie in sheep, have long been recognized, our understanding of their epidemiology and pathogenesis is still in its early stages. Progress is hampered by the lengthy incubation periods and the lack of effective ways of monitoring and characterizing these agents. Protease-resistant conformers of the prion protein (PrP), known as the "scrapie form" (PrP(Sc)), are used as disease markers, and for taxonomic purposes, in correlation with clinical, pathological, and genetic data. In humans, prion diseases can arise sporadically (sCJD) or genetically (gCJD and others), caused by mutations in the PrP-gene (PRNP), or as a foodborne infection, with the agent of bovine spongiform encephalopathy (BSE) causing variant CJD (vCJD). Person-to-person spread of human prion disease has only been known to occur following cannibalism (kuru disease in Papua New Guinea) or through medical or surgical treatment (iatrogenic CJD, iCJD). In contrast, scrapie in small ruminants and chronic wasting disease (CWD) in cervids behave as infectious diseases within these species. Recently, however, so-called atypical forms of prion diseases have been discovered in sheep (atypical/Nor98 scrapie) and in cattle, BSE-H and BSE-L. These maladies resemble sporadic or genetic human prion diseases and might be their animal equivalents. This hypothesis also raises the significant public health question of possible epidemiological links between these diseases and their counterparts in humans.
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Loiacono CM, Beckwith N, Kunkle RA, Orcutt D, Hall SM. Detection of PrP(Sc) in formalin-fixed, paraffin-embedded tissue by Western blot differentiates classical scrapie, Nor98 scrapie, and bovine spongiform encephalopathy. J Vet Diagn Invest 2010; 22:684-9. [PMID: 20807921 DOI: 10.1177/104063871002200502] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Transmissible, spongiform encephalopathies including bovine spongiform encephalopathy (BSE) and scrapie are fatal neurodegenerative disorders associated with the presence of an infectious abnormal isoform of normal mammalian proteins called prions. Identification of the prion protein associated with scrapie (PrP(Sc)) in the central nervous system is typically based upon immunoassays including immunohistochemistry (IHC) using formalin-fixed tissues or Western blot (WB) assays using fresh and/or frozen, non-formalin-fixed tissues. Each assay can discriminate between BSE, classical scrapie, and a previously reported strain of scrapie recently identified in the United States named Nor98 scrapie. Different tissue samples are required from the same animal to run these 2 different immunoassays. This may result in inconsistent test results for the same animal. Sampling problems such as collecting insufficient volumes of fresh tissue or less than optimal anatomic location of brainstem for IHC can affect the ability of the test procedures to offer definitive and discriminatory results. Recently, a WB method using formalin-fixed, paraffin-embedded (FFPE) tissue to identify PrP(Sc) was developed that successfully identified PrP(Sc) in sheep affected by classical scrapie. In the current study, the use of this technique to produce discriminatory results identifying classical BSE in bovine tissue and both classical and Nor98 scrapie in ovine tissue using paraffin-embedded brain samples is described. Protein-banding patterns from WB using FFPE tissue were similar to protein-banding patterns produced by WB assays utilizing fresh tissues from the same animals, and results correlated well with the IHC PrP(Sc)-positive staining present in the cerebellum and obex regions of brain samples from these animals.
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Affiliation(s)
- Christina M Loiacono
- Animal and Plant Health Inspection Services, National Veterinary Services Laboratories, Pathobiology Laboratory, U.S. Department of Agriculture, Ames, IA 50010, USA.
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Del Rio Vilas VJ, Vink WD, Hubbard R. A case-control study of atypical scrapie in GB sheep flocks. Prev Vet Med 2010; 96:241-51. [PMID: 20615563 DOI: 10.1016/j.prevetmed.2010.06.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Revised: 05/16/2010] [Accepted: 06/08/2010] [Indexed: 10/19/2022]
Abstract
Wide-scale scrapie surveillance started in 2002 in the EU. As a result, a new form of scrapie was detected which has been referred to as atypical scrapie. Here we present a case-control study conducted on British sheep farms to increase our understanding of the disease and potential risk factors at holding level. Forty case and 120 control holdings were traced from the confirmed atypical results in the scrapie surveillance programme in Great Britain during the period 2002-2007. A detailed questionnaire was completed by interview to record data on holding-specific management variables. A combination of generalized additive, generalized linear and Bayesian models returned 3 variables clearly associated with an increase in the odds of atypical scrapie: presence of two sheep breeds (Welsh Mountain and Cheviot) and flock type (store/fattening flocks). A fourth variable, the number of visits by veterinarians to the holding exerted a protective effect. Various other variables were significantly associated with the outcome, but at a somewhat lower level of confidence; for example, the size of the holding and the presence on the farm of concentrates intended for animals other than sheep.
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31
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Lampo E, Van den Broeck W, Willemarck N, Van Poucke M, Casteleyn CR, De Spiegelaere W, Van Zeveren A, Peelman LJ. Distribution of the Shadoo protein in the ovine brain assessed by immunohistochemistry. Res Vet Sci 2010; 90:372-8. [PMID: 20667569 DOI: 10.1016/j.rvsc.2010.06.027] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2009] [Revised: 06/14/2010] [Accepted: 06/28/2010] [Indexed: 11/18/2022]
Abstract
Shadow of prion protein is a gene potentially involved in the pathogenesis of prion diseases. However, the Shadoo protein encoded by this gene has not yet been studied in sheep, an important species in prion matters. Therefore, we developed a polyclonal antibody against ovine Shadoo and assessed the presence and distribution of this protein in the ovine brain by immunohistochemistry. The strongest staining level was found in the cerebellum (especially in the Purkinje cells) and in the pons, but cerebrum, hippocampus, pituitary gland, medulla oblongata, thalamus and hypothalamus were also immunopositive. Remarkably, a typical granular pattern was seen in most of the tested brain tissues, which might indicate that Shadoo is primarily expressed at synapses. The results of this study and the availability of an ovine anti-Shadoo antibody can contribute to future research on the function of Shadoo and on its potential involvement in prion diseases.
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Affiliation(s)
- E Lampo
- Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Heidestraat 19, B-9820 Merelbeke, Belgium
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32
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Griffiths PC, Spiropoulos J, Lockey R, Tout AC, Jayasena D, Plater JM, Chave A, Green RB, Simonini S, Thorne L, Dexter I, Balkema-Buschmann A, Groschup MH, Béringue V, Le Dur A, Laude H, Hope J. Characterization of atypical scrapie cases from Great Britain in transgenic ovine PrP mice. J Gen Virol 2010; 91:2132-2138. [PMID: 20392900 DOI: 10.1099/vir.0.018986-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Twenty-four atypical scrapie cases from sheep with different prion protein genotypes from Great Britain were transmitted to transgenic tg338 and/or TgshpXI mice expressing sheep PrP alleles, but failed to transmit to wild-type mice. Mean incubation periods were 200-300 days in tg338 mice and 300-500 days in TgshpXI mice. Survival times in C57BL/6 and VM/Dk mice were >700 days. Western blot analysis of mouse brain samples revealed similar multi-band, protease-resistant prion protein (PrP(res)) profiles, including an unglycosylated band at approximately 8-11 kDa, which was shown by antibody mapping to correspond to the approximately 93-148 aa portion of the PrP molecule. In transgenic mice, the incubation periods, Western blot PrP(res) profiles, brain lesion profiles and abnormal PrP (PrP(Sc)) distribution patterns produced by the Great Britain atypical scrapie isolates were similar and compatible with the biological characteristics of other European atypical scrapie or Nor98 cases.
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Affiliation(s)
- Peter C Griffiths
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - John Spiropoulos
- Neuropathology Section, Pathology Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Richard Lockey
- Neuropathology Section, Pathology Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Anna C Tout
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Dhanushka Jayasena
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Jane M Plater
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Alun Chave
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Robert B Green
- Neuropathology Section, Pathology Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Sarah Simonini
- Neuropathology Section, Pathology Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Leigh Thorne
- Molecular Pathogenesis and Genetics Department, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Ian Dexter
- Animal Services Unit, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
| | - Anne Balkema-Buschmann
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, 17493 Greifswald-Insel Riems, Germany
| | - Martin H Groschup
- Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, 17493 Greifswald-Insel Riems, Germany
| | - Vincent Béringue
- Virologie Immunologie Moléculaires, U892, Institut National de la Recherche Agronomique, 78350 Jouy-en-Josas, France
| | - Annick Le Dur
- Virologie Immunologie Moléculaires, U892, Institut National de la Recherche Agronomique, 78350 Jouy-en-Josas, France
| | - Hubert Laude
- Virologie Immunologie Moléculaires, U892, Institut National de la Recherche Agronomique, 78350 Jouy-en-Josas, France
| | - James Hope
- Centre for Epidemiology and Risk Analysis, Veterinary Laboratories Agency, Addlestone, Surrey KT15 3NB, UK
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33
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Rodríguez-Martínez AB, Garrido JM, Maza S, Benedicto L, Geijo M, Gómez N, Minguijón E, Benestad SL, Juste RA. Atypical/Nor98 scrapie in the Basque Country: a case report of eight outbreaks. BMC Vet Res 2010; 6:17. [PMID: 20346155 PMCID: PMC2859363 DOI: 10.1186/1746-6148-6-17] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Accepted: 03/26/2010] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Since 2002, an active surveillance program for transmissible spongiform encephalopathy in small ruminants in European Union countries allowed identification of a considerable number of atypical cases with similarities to the previously identified atypical scrapie cases termed Nor98. CASE PRESENTATION Here we report molecular and neuropathological features of eight atypical/Nor98 scrapie cases detected between 2002 and 2009. Significant features of the affected sheep included: their relatively high ages (mean age 7.9 years, range between 4.3 and 12.8), their breed (all Latxa) and their PRNP genotypes (AFRQ/ALRQ, ALRR/ALRQ, AFRQ/AFRQ, AFRQ/AHQ, ALRQ/ALRH, ALRQ/ALRQ). All the sheep were confirmed as atypical scrapie by immunohistochemistry and immunoblotting. Two cases presented more PrP immunolabelling in cerebral cortex than in cerebellum. CONCLUSIONS This work indicates that atypical scrapie constitutes the most common small ruminant transmissible spongiform encephalopathy form in Latxa sheep in the Spanish Basque Country. Moreover, a new genotype (ALRQ/ALRH) was found associated to atypical scrapie.
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Affiliation(s)
| | - Joseba M Garrido
- Department of Animal Health. Neiker-Tecnalia, 48160 Derio. Bizkaia. Spain
| | - Sonia Maza
- Department of Animal Health. Neiker-Tecnalia, 48160 Derio. Bizkaia. Spain
| | - Leyre Benedicto
- Department of Animal Health. Neiker-Tecnalia, 48160 Derio. Bizkaia. Spain
| | - Mariví Geijo
- Department of Animal Health. Neiker-Tecnalia, 48160 Derio. Bizkaia. Spain
| | - Nieves Gómez
- Department of Animal Health. Neiker-Tecnalia, 48160 Derio. Bizkaia. Spain
| | | | - Sylvie L Benestad
- National Veterinary Institute, Department of Pathology, Postboks 750 Sentrum. 0106 Oslo. Norway
| | - Ramón A Juste
- Department of Animal Health. Neiker-Tecnalia, 48160 Derio. Bizkaia. Spain
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34
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Orge L, Oliveira A, Machado C, Lima C, Ochoa C, Silva J, Carvalho R, Tavares P, Almeida P, Ramos M, Pinto MJ, Simas JP. Putative emergence of classical scrapie in a background of enzootic atypical scrapie. J Gen Virol 2010; 91:1646-50. [PMID: 20164262 DOI: 10.1099/vir.0.018879-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Active transmissible spongiform encephalopathy (TSE) surveillance in small ruminants across Europe was implemented in 2002 following the epizootic of bovine spongiform encephalopathy. Here, we report the potential emergence of classical scrapie in Portugal, in a background of enzootic atypical scrapie. Between 2003 and 2008, 375,459 small ruminants were screened in total, with 328 animals confirmed positive for NOR98 atypical scrapie. During this period, the prevalence rate of atypical scrapie for all years combined was 0.0874% across the country. In this scenario, classical scrapie emerged as a single outbreak in 2008, with 12 identified cases. In contrast to other European countries, where classical scrapie has been enzootic for decades, these data indicate that, in Portugal, atypical scrapie is the predominant form of TSE. The findings reported here will have implications for the control of classical scrapie in Portugal, namely in terms of keeping the country free of enzootic classical scrapie.
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Affiliation(s)
- Leonor Orge
- Laboratório Nacional de Investigação Veterinária, Instituto Nacional de Recursos Biológicos, I. P., Portugal
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35
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36
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Evidence for maternal transmission of scrapie in naturally affected flocks. Prev Vet Med 2009; 93:121-8. [PMID: 19945758 DOI: 10.1016/j.prevetmed.2009.10.013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2007] [Revised: 10/14/2009] [Accepted: 10/16/2009] [Indexed: 11/24/2022]
Abstract
It has been known for many years that the offspring of scrapie affected ewes are at increased risk of developing scrapie but whether this is simply the result of an increased genetic susceptibility or transmission of infection has always been unclear. To contribute to clarify this we analysed the data collected in a detailed study of scrapie occurrence in a number of naturally affected commercial sheep flocks in Great Britain (GB) to investigate the association between PrP genotype and parental scrapie status and the incidence of scrapie. Our analyses confirmed the strong association between PrP genotype and the incidence of scrapie found in previous studies and a low incidence of scrapie in animals carrying the ARR allele and a high risk in homozygous VRQ animals. However, we also demonstrate an increased incidence of scrapie in the offspring of scrapie affected ewes controlling for the confounding effect of PrP genotype, but no increased scrapie incidence in the offspring of scrapie affected sires. Our results suggest that some of the increased incidence of scrapie in the offspring of scrapie affected ewes is the result of transmission of infection from mother to offspring. Our results confirm that a breeding policy aimed at decreasing the genetic susceptibility of the population should decrease the incidence of scrapie and that removing the offspring of scrapie affected animals from affected flocks could contribute to the control of this disease.
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37
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Abstract
Transmissible spongiform encephalopathies (TSEs) are inevitably lethal neurodegenerative diseases that affect humans and a large variety of animals. The infectious agent responsible for TSEs is the prion, an abnormally folded and aggregated protein that propagates itself by imposing its conformation onto the cellular prion protein (PrPC) of the host. PrPCis necessary for prion replication and for prion-induced neurodegeneration, yet the proximal causes of neuronal injury and death are still poorly understood. Prion toxicity may arise from the interference with the normal function of PrPC, and therefore, understanding the physiological role of PrPCmay help to clarify the mechanism underlying prion diseases. Here we discuss the evolution of the prion concept and how prion-like mechanisms may apply to other protein aggregation diseases. We describe the clinical and the pathological features of the prion diseases in human and animals, the events occurring during neuroinvasion, and the possible scenarios underlying brain damage. Finally, we discuss potential antiprion therapies and current developments in the realm of prion diagnostics.
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38
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Loiacono CM, Thomsen BV, Hall SM, Kiupel M, Sutton D, O'Rourke K, Barr B, Anthenill L, Keane D. Nor98 scrapie identified in the United States. J Vet Diagn Invest 2009; 21:454-63. [PMID: 19564493 DOI: 10.1177/104063870902100406] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
A distinct strain of scrapie identified in sheep of Norway in 1998 has since been identified in numerous countries throughout Europe. The disease is known as Nor98 or Nor98-like scrapie, among other names. Distinctions between classic scrapie and Nor98 scrapie are made based on histopathology and immunodiagnostic results. There are also differences in the epidemiology, typical signalment, and likelihood of clinical signs being observed. In addition, sheep that have genotypes associated with resistance to classic scrapie are not spared from Nor98 disease. The various differences between classic and Nor98 scrapie have been consistently reported in the vast majority of cases described across Europe. The current study describes in detail the pathologic changes and diagnostic results of the first 6 cases of Nor98 scrapie disease diagnosed in sheep of the United States.
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39
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Wemheuer WM, Benestad SL, Wrede A, Wemheuer WE, Brenig B, Bratberg B, Schulz-Schaeffer WJ. Detection of classical and atypical/Nor98 scrapie by the paraffin-embedded tissue blot method. Vet Rec 2009; 164:677-81. [PMID: 19483208 DOI: 10.1136/vr.164.22.677] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The paraffin-embedded tissue (PET) blot method was used to investigate sections of the central nervous system and lymphatic tissues from 24 cases of classical scrapie and 25 cases of atypical/Nor98 scrapie in sheep and four healthy control sheep. The PET blot detected deposits of PrP(Sc) in the brain tissue of all 49 sheep with scrapie but no PrP(Sc) labelling could be detected in the control sheep. By contrast, not all the atypical/Nor98 scrapie cases were detectable by immunohistochemistry. The high sensitivity of the PET blot method made it possible to observe that in some atypical/Nor98 cases, deposits of PrP(Sc) may be restricted to supratentorial brain structures and that the diagnosis may be missed when only testing the obex area, where deposits are common in classical scrapie, and the cerebellar structures, where deposits are considered to be common in atypical/Nor98 cases.
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Affiliation(s)
- W M Wemheuer
- Prion and Dementia Research Unit, Department of Neuropathology, University Medical Centre, Göttingen, 37075 Göttingen, Germany
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40
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Detection of typical and atypical bovine spongiform encephalopathy and scrapie prion strains by prion protein motif-grafted antibodies. J Gen Virol 2009; 90:1048-1053. [DOI: 10.1099/vir.2008.007120-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
To evaluate further the reactivity of prion-specific monoclonal antibodies containing the 89–112 or 136–158 prion protein (PrP) polypeptides, immunoprecipitations were performed on brain extracts from Italian bovines, sheep and goats with transmissible spongiform encephalopathies. No binding of IgG 89–112 or IgG 136–158 to PrP in normal brain extracts was detected. Conversely, both reagents immunoprecipitated PrP from bovine and bovine amyloidotic spongiform encephalopathies, and from typical and atypical scrapie brain extracts. The immunoprecipitated PrP bands mirrored the Western blot (WB) profile of the different prion strains, indicating universal affinity of two independent PrP regions for disease-associated PrP conformers regardless of species source and strain properties. Immunoprecipitation with motif-grafted antibodies increased the sensitivity of conventional detection methods based on centrifugation followed by WB, which was confirmed by assay of diluted samples using both methods. These reagents or derivative molecules may thus find broad applications in prion detection and research.
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41
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Laude H, Béringue V. [Newly discovered forms of prion diseases in ruminants]. PATHOLOGIE-BIOLOGIE 2009; 57:117-126. [PMID: 18848406 DOI: 10.1016/j.patbio.2008.07.023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Accepted: 07/03/2008] [Indexed: 05/26/2023]
Abstract
Transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative diseases caused by unconventional agents, the prions. They are characterised by the accumulation in infected tissues of an abnormally folded form of the host-encoded prion protein (PrP). This pathological form is partially resistant to protease digestion, leading to the production of so-called PrP(res) fragments. Different isolates from the same host species may show different eletrophoretic profiles, reflecting the existence of different prion strains. The active surveillance of ruminant TSEs implemented in European countries, based on a large-scale biochemical testing of brain tissue samples from carcasses, has revealed PrP(res) profiles unnoticed so far. Experimental transmission of these atypical cases to various transgenic mouse lines has led to the recognition of a novel scrapie strain in sheep and goats, called Nor98, and of two variant strains of spongiform encephalopathy in cattle. This review is aimed at summarising the current knowledge on these newly recognised forms of ruminants TSEs, and at discussing their possible origin and potential implications in terms of animal and human health.
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Affiliation(s)
- H Laude
- INRA, U892, virologie immunologie moléculaires, domaine de Vilvert, 78350 Jouy-en-Josas, France.
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42
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Gubbins S. Prevalence of sheep infected with classical scrapie in Great Britain: integrating multiple sources of surveillance data for 2002. J R Soc Interface 2008; 5:1343-51. [PMID: 18348959 DOI: 10.1098/rsif.2008.0021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Estimates for the prevalence of sheep infected with classical scrapie are essential for assessing the efficacy of control strategies that have been implemented in Great Britain (GB). Here a back-calculation approach was used to estimate the prevalence in the GB national flock by integrating data on reported cases and the results of abattoir and fallen stock surveys for 2002. Prevalence estimates ranged from 0.33 to 2.06%, depending on the estimates used for the frequencies of prion protein (PrP) genotypes in the national flock and the stage of incubation at which the diagnostic tests used are able to detect infected animals. The risk of infection was found to be higher than that of clinical disease, especially in those PrP genotypes that have a later age at onset of clinical disease. Moreover, results suggest that a high proportion (more than 55%) of infected animals surviving to disease onset die on farm before clinical signs become apparent, which helps account for the high observed prevalence in the fallen stock compared with the abattoir survey. The analyses indicated that attention needs to be given to identifying the stage of incubation at which diagnostic tests are able to detect infected animals and obtaining better demographic data for the GB national flock.
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Affiliation(s)
- Simon Gubbins
- Pirbright Laboratory, Institute for Animal Health, Pirbright, Surrey, UK.
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43
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Neuroanatomical distribution of abnormal prion protein in naturally occurring atypical scrapie cases in Great Britain. Acta Neuropathol 2008; 116:547-59. [PMID: 18797889 DOI: 10.1007/s00401-008-0433-8] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Revised: 09/01/2008] [Accepted: 09/01/2008] [Indexed: 10/21/2022]
Abstract
Scrapie belongs to a group of diseases known as the transmissible spongiform encephalopathies or prion diseases. Two different categories of naturally occurring scrapie have been identified: classical scrapie, which was first recorded around 1750, and atypical scrapie or 'Nor-98', which was first identified in Norway in 1998. The molecular characteristics of atypical scrapie have been well defined, but detailed descriptions of the neuropathological phenotype are rare since the majority of cases have been detected through active surveillance programmes where only brainstem and cerebellum are collected for statutory diagnosis. In order to characterise the neuropathology of naturally occurring atypical scrapie in sheep, we examined multiple brain levels from 15 whole brains from field cases of atypical scrapie, both clinical suspects and fallen stock, collected in Great Britain between 2004 and 2006. We found that the distribution of disease-associated prion protein (PrP(Sc)) and vacuolation in atypical scrapie cases are very different to both classical scrapie and experimental bovine spongiform encephalopathy in sheep. Immunolabelling for PrP(Sc) is mild and restricted at the obex and more intense and widespread rostrally, particularly in the cerebellum, substantia nigra, thalamus and basal nuclei. Intracellular immunolabelling types are not seen, but distinctive white matter immunolabelling is widespread. Vacuolation associated with PrP(Sc) deposits was not observed in the brainstem neuroanatomical areas commonly affected in classical scrapie and bovine spongiform encephalopathy, but was instead most prominent in the cerebellar cortex and neocortex. This is the largest comprehensive descriptive study of atypical scrapie pathology to date, and provides baseline data against which other natural or experimental cases can be compared. It also reinforces the current recommendation to collect cerebellum in addition to brainstem to enable confident confirmation of this distinct disease phenotype within surveillance programmes.
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44
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Kittelberger R, Mackereth GF, Sewell M, Keall J, Clough R, Pigott C, O'Keefe JS. Specificity of non-structural protein enzyme-linked immunosorbent assays for the detection of serum antibodies against foot-and-mouth disease virus in a target population in New Zealand. N Z Vet J 2008; 56:227-32. [DOI: 10.1080/00480169.2008.36838] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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45
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Del Rio Vilas V, Böhning D. Application of one-list capture–recapture models to scrapie surveillance data in Great Britain. Prev Vet Med 2008; 85:253-66. [DOI: 10.1016/j.prevetmed.2008.02.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Revised: 12/21/2007] [Accepted: 02/04/2008] [Indexed: 10/22/2022]
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Fediaevsky A, Tongue SC, Nöremark M, Calavas D, Ru G, Hopp P. A descriptive study of the prevalence of atypical and classical scrapie in sheep in 20 European countries. BMC Vet Res 2008; 4:19. [PMID: 18544152 PMCID: PMC2442063 DOI: 10.1186/1746-6148-4-19] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2008] [Accepted: 06/10/2008] [Indexed: 12/03/2022] Open
Abstract
Background The development of active surveillance programmes for transmissible spongiform encephalopathies of small ruminants across Europe has led to the recent identification of a previously undetected form of ovine prion disease, 'atypical' scrapie. Knowledge of the epidemiology of this disease is still limited, as is whether it represents a risk for animal and/or public health. The detection of atypical scrapie has been related to the use of only some of the EU agreed rapid tests. Information about the rapid tests used is not, as yet, available from public reports on the surveillance of transmissible spongiform encephalopathies in small ruminants. We collected detailed results of active surveillance from European countries to estimate and to compare the prevalence of atypical scrapie and classical scrapie in sheep for each country stratified by each surveillance stream; healthy slaughtered and found dead adult sheep. Results From the 20 participating countries, it appeared that atypical scrapie was detected in Europe wherever the conditions necessary for its diagnosis were present. In most countries, atypical scrapie and classical scrapie occurred at low prevalence level. The classical scrapie prevalence estimates were more variable than those for atypical scrapie, which appeared remarkably homogeneous across countries, surveillance streams and calendar years of surveillance. Differences were observed in the age and genotype of atypical scrapie and classical scrapie cases that are consistent with previous published findings. Conclusion This work suggests that atypical scrapie is not rare compared to classical scrapie. The homogeneity of its prevalence, whatever the country, stream of surveillance or year of detection, contrasts with the epidemiological pattern of classical scrapie. This suggests that the aetiology of atypical scrapie differs from that of classical scrapie.
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Affiliation(s)
- Alexandre Fediaevsky
- AFSSA-Lyon, Unité Epidémiologie, 31 Avenue Tony Garnier, 69364 Lyon Cedex 07, France.
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Foster J, Toovey L, McKenzie C, Chong A, Parnham D, Drummond D, Hunter N. Atypical scrapie in a sheep in a closed uk
flock with endemic classical natural scrapie. Vet Rec 2008; 162:723-4. [PMID: 18515761 DOI: 10.1136/vr.162.22.723] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- J. Foster
- Roslin Institute; Neuropathogenesis Unit; Ogston Building, West Mains Road Edinburgh EH9 3JF
| | - L. Toovey
- Roslin Institute; Neuropathogenesis Unit; Ogston Building, West Mains Road Edinburgh EH9 3JF
| | - C. McKenzie
- Roslin Institute; Neuropathogenesis Unit; Ogston Building, West Mains Road Edinburgh EH9 3JF
| | - A. Chong
- Roslin Institute; Neuropathogenesis Unit; Ogston Building, West Mains Road Edinburgh EH9 3JF
| | - D. Parnham
- Roslin Institute; Neuropathogenesis Unit; Ogston Building, West Mains Road Edinburgh EH9 3JF
| | - D. Drummond
- Roslin Institute; Neuropathogenesis Unit; Ogston Building, West Mains Road Edinburgh EH9 3JF
| | - N. Hunter
- Roslin Institute; Neuropathogenesis Unit; Ogston Building, West Mains Road Edinburgh EH9 3JF
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Aguzzi A, Sigurdson C, Heikenwaelder M. Molecular mechanisms of prion pathogenesis. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2008; 3:11-40. [PMID: 18233951 DOI: 10.1146/annurev.pathmechdis.3.121806.154326] [Citation(s) in RCA: 253] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Prion diseases are infectious neurodegenerative diseases occurring in humans and animals with an invariably lethal outcome. One fundamental mechanistic event in prion diseases is the aggregation of aberrantly folded prion protein into large amyloid plaques and fibrous structures associated with neurodegeneration. The cellular prion protein (PrPC) is absolutely required for disease development, and prion knockout mice are not susceptible to prion disease. Prions accumulate not only in the central nervous system but also in lymphoid organs, as shown for new variant and sporadic Creutzfeldt-Jakob patients and for some animals. To date it is largely accepted that prions consist primarily of PrPSc, a misfolded and aggregated beta-sheet-rich isoform of PrPC. However, PrPSc may or may not be completely congruent with the infectious moiety. Here, we discuss the molecular mechanisms leading to neurodegeneration, the role of the immune system in prion pathogenesis, and the existence of prion strains that appear to have different tropisms and biochemical characteristics.
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Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zürich, CH-8091 Zürich, Switzerland.
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Dagleish MP, Rodger SM, Simmons MM, Finlayson J, Buxton D, Chianini F. Atypical scrapie in a sheep in Scotland. Vet Rec 2008; 162:518-9. [DOI: 10.1136/vr.162.16.518] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- M. P. Dagleish
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ
| | - S. M. Rodger
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ
| | - M. M. Simmons
- Veterinary Laboratories Agency - Weybridge; Woodham Lane, New Haw Addlestone Surrey KT15 3NB
| | - J. Finlayson
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ
| | - D. Buxton
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ
| | - F. Chianini
- Moredun Research Institute; Pentlands Science Park, Bush Loan Penicuik Midlothian EH26 0PZ
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Konold T, Moore SJ, Bellworthy SJ, Simmons HA. Evidence of scrapie transmission via milk. BMC Vet Res 2008; 4:14. [PMID: 18397513 PMCID: PMC2374774 DOI: 10.1186/1746-6148-4-14] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Accepted: 04/08/2008] [Indexed: 11/10/2022] Open
Abstract
Background The risk of scrapie infection increases with increased duration and proximity of contact between sheep at lambing. Scrapie infectivity has not been detected in milk but cellular prion protein, the precursor of disease-associated prion protein PrPd, has been found in milk from ruminants. To determine whether milk is able to transmit scrapie, 18 lambs with a prion protein genotype associated with high susceptibility to scrapie (VRQ/VRQ) were fed milk from twelve scrapie-affected ewes of the same genotype, and 15 VRQ/VRQ sheep reared on scrapie-free dams served as controls. Results Three lambs fed milk from scrapie-affected ewes were culled due to intercurrent diseases at 43, 44 and 105 days of age respectively, and PrPd was detected in the distal ileum of the first two lambs, whilst PrPd was not found in lymphoreticular tissues in the third lamb. A control lamb, housed in a separate pen and culled at 38 days of age, was also negative for PrPd in a range of tissues. Samples of recto-anal mucosa associated lymphoid tissue collected from the remaining 15 live lambs at seven months of age (between five to seven months after mixing) were positive for PrPd in the scrapie milk recipients, whereas PrPd was not detected in the remaining 14 controls at that time. A subsequent sample collected from control lambs revealed PrPd accumulation in two of five lambs eight months after mixing with scrapie milk recipients suggestive of an early stage of infection via lateral transmission. By contrast, the control sheep housed in the same building but not mixed with the scrapie milk recipients were still negative for PrPd. Conclusion The presence of PrPd in distal ileum and rectal mucosa indicates transmission of scrapie from ewe to lamb via milk (or colostrum) although it is not yet clear if such cases would go on to develop clinical disease. The high level of infection in scrapie-milk recipients revealed by rectal mucosal testing at approximately seven months of age may be enhanced or supplemented by intra-recipient infection as these lambs were mixed together after feeding with milk from scrapie-affected ewes and we also observed lateral transmission from these animals to lambs weaned from scrapie-free ewes.
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Affiliation(s)
- Timm Konold
- Neuropathology, Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
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