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Soto P, Bravo-Risi F, Kramm C, Gamez N, Benavente R, Bonilla DL, Reed JH, Lockwood M, Spraker TR, Nichols T, Morales R. Nasal bots carry relevant titers of CWD prions in naturally infected white-tailed deer. EMBO Rep 2024; 25:334-350. [PMID: 38191872 PMCID: PMC10883265 DOI: 10.1038/s44319-023-00003-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 10/31/2023] [Accepted: 11/07/2023] [Indexed: 01/10/2024] Open
Abstract
Chronic wasting disease (CWD) is a prion disease affecting farmed and free-ranging cervids. CWD is rapidly expanding across North America and its mechanisms of transmission are not completely understood. Considering that cervids are commonly afflicted by nasal bot flies, we tested the potential of these parasites to transmit CWD. Parasites collected from naturally infected white-tailed deer were evaluated for their prion content using the protein misfolding cyclic amplification (PMCA) technology and bioassays. Here, we describe PMCA seeding activity in nasal bot larvae collected from naturally infected, nonclinical deer. These parasites efficiently infect CWD-susceptible mice in ways suggestive of high infectivity titers. To further mimic environmental transmission, bot larvae homogenates were mixed with soils, and plants were grown on them. We show that both soils and plants exposed to CWD-infected bot homogenates displayed seeding activity by PMCA. This is the first report describing prion infectivity in a naturally occurring deer parasite. Our data also demonstrate that CWD prions contained in nasal bots interact with environmental components and may be relevant for disease transmission.
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Affiliation(s)
- Paulina Soto
- Department of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, USA
- Centro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O'Higgins, Santiago, Chile
| | - Francisca Bravo-Risi
- Department of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, USA
- Centro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O'Higgins, Santiago, Chile
| | - Carlos Kramm
- Department of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Nazaret Gamez
- Department of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Rebeca Benavente
- Department of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, USA
| | - Denise L Bonilla
- United States Department of Agriculture, Animal Plant Health Inspection Service, Veterinary Services, Fort Collins, CO, USA
| | - J Hunter Reed
- Texas Parks and Wildlife Department, Kerrville, TX, USA
| | | | - Terry R Spraker
- Colorado State University Diagnostic Medical Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
| | - Tracy Nichols
- United States Department of Agriculture, Animal Plant Health Inspection Service, Veterinary Services, Fort Collins, CO, USA
| | - Rodrigo Morales
- Department of Neurology, The University of Texas Health Science Center at Houston, Houston, TX, USA.
- Centro Integrativo de Biologia y Quimica Aplicada (CIBQA), Universidad Bernardo O'Higgins, Santiago, Chile.
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2
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Mathiason CK. Large animal models for chronic wasting disease. Cell Tissue Res 2023; 392:21-31. [PMID: 35113219 PMCID: PMC8811588 DOI: 10.1007/s00441-022-03590-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 01/19/2022] [Indexed: 11/30/2022]
Abstract
Chronic wasting disease (CWD) is a fatal neurodegenerative prion disease of cervid species including deer, elk, moose and reindeer. The disease has shown both geographic and species expansion since its discovery in the late 1960's and is now recognized in captive and free-ranging cervid populations in North America, Asia and Europe. The facile transmission of CWD is unique among prion diseases and has resulted in growing concern for cervid populations and human public health. The development of native cervid host models with longitudinal monitoring has revealed new insights about CWD pathogenesis and transmission dynamics. More than 20 years of experimental studies conducted in these models, using biologically relevant routes of infection, have led to better understanding of many aspect of CWD infections. This review addresses some of these insights, including: (i) the temporal intra-host trafficking of CWD prions in tissues and bodily fluids, (ii) the presence of infectivity shed in bodily excretions that may help explain the facile transmission of CWD, (iii) mother-to-offspring CWD transmission, (iv) the influence of some Prnp polymorphisms on CWD susceptibility, and (vi) continued development of vaccine strategies to mitigate CWD.
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Affiliation(s)
- C K Mathiason
- College of Veterinary Medicine and Biomedical Sciences, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, United States, 80523.
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3
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Sun JL, Telling GC. New developments in prion disease research using genetically modified mouse models. Cell Tissue Res 2023; 392:33-46. [PMID: 36929219 DOI: 10.1007/s00441-023-03761-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 03/03/2023] [Indexed: 03/18/2023]
Abstract
While much of what we know about the general principles of protein-based information transfer derives from studies of experimentally adapted rodent prions, these laboratory strains are limited in their ability to recapitulate features of human and animal prions and the diseases they produce. Here, we review how recent approaches using genetically modified mice have informed our understanding of naturally occurring prion diseases, their strain properties, and the factors controlling their transmission and evolution. In light of the increasing importance of chronic wasting disease, the application of mouse transgenesis to study this burgeoning and highly contagious prion disorder, in particular recent insights derived from gene-targeting approaches, will be a major focus of this review.
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Affiliation(s)
- Julianna L Sun
- Prion Research Center, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, USA
| | - Glenn C Telling
- Prion Research Center, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, USA.
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4
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Chronic wasting disease prions in mule deer interdigital glands. PLoS One 2022; 17:e0275375. [PMID: 36190981 PMCID: PMC9529147 DOI: 10.1371/journal.pone.0275375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 09/13/2022] [Indexed: 11/19/2022] Open
Abstract
Chronic wasting disease (CWD) is a geographically expanding, fatal neurodegenerative disease in cervids. The disease can be transmitted directly (animal-animal) or indirectly via infectious prions shed into the environment. The precise mechanisms of indirect CWD transmission are unclear but known sources of the infectious prions that contaminate the environment include saliva, urine and feces. We have previously identified PrPC expression in deer interdigital glands, sac-like exocrine structures located between the digits of the hooves. In this study, we assayed for CWD prions within the interdigital glands of CWD infected deer to determine if they could serve as a source of prion shedding and potentially contribute to CWD transmission. Immunohistochemical analysis of interdigital glands from a CWD-infected female mule deer identified disease-associated PrPCWD within clusters of infiltrating leukocytes adjacent to sudoriferous and sebaceous glands, and within the acrosyringeal epidermis of a sudoriferous gland tubule. Proteinase K-resistant PrPCWD material was amplified by serial protein misfolding cyclic amplification (sPMCA) from soil retrieved from between the hoof digits of a clinically affected mule deer. Blinded testing of interdigital glands from 11 mule deer by real-time quake-induced conversion (RT-QuIC) accurately identified CWD-infected animals. The data described suggests that interdigital glands may play a role in the dissemination of CWD prions into the environment, warranting future investigation.
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5
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Ness A, Jacob A, Saboraki K, Otero A, Gushue D, Martinez Moreno D, de Peña M, Tang X, Aiken J, Lingle S, McKenzie D. Cellular prion protein distribution in the vomeronasal organ, parotid, and scent glands of white-tailed deer and mule deer. Prion 2022; 16:40-57. [PMID: 35634740 PMCID: PMC9154781 DOI: 10.1080/19336896.2022.2079888] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Chronic wasting disease (CWD) is a contagious and fatal transmissible spongiform encephalopathy affecting species of the cervidae family. CWD has an expanding geographic range and complex, poorly understood transmission mechanics. CWD is disproportionately prevalent in wild male mule deer and male white-tailed deer. Sex and species influences on CWD prevalence have been hypothesized to be related to animal behaviours that involve deer facial and body exocrine glands. Understanding CWD transmission potential requires a foundational knowledge of the cellular prion protein (PrPC) in glands associated with cervid behaviours. In this study, we characterized the presence and distribution of PrPC in six integumentary and two non-integumentary tissues of hunter-harvested mule deer (Odocoileus hemionus) and white-tailed deer (O. virginianus). We report that white-tailed deer expressed significantly more PrPC than their mule deer in the parotid, metatarsal, and interdigital glands. Females expressed more PrPC than males in the forehead and preorbital glands. The distribution of PrPC within the integumentary exocrine glands of the face and legs were localized to glandular cells, hair follicles, epidermis, and immune cell infiltrates. All tissues examined expressed sufficient quantities of PrPC to serve as possible sites of prion initial infection, propagation, and shedding.
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Affiliation(s)
- Anthony Ness
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
| | - Aradhana Jacob
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
| | - Kelsey Saboraki
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba, Canada
| | - Alicia Otero
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Enfermedades Transmisibles Emergentes, Universidad de ZaragozaCentro de Encefalopatías y , Zaragoza, Spain
| | - Danielle Gushue
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
| | - Diana Martinez Moreno
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
| | - Melanie de Peña
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba, Canada
| | - Xinli Tang
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada
| | - Judd Aiken
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
- Department of Agriculture, Food and Nutritional Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Susan Lingle
- Department of Biology, University of Winnipeg, Winnipeg, Manitoba, Canada
| | - Debbie McKenzie
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
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6
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Susceptibility of Beavers to Chronic Wasting Disease. BIOLOGY 2022; 11:biology11050667. [PMID: 35625395 PMCID: PMC9137852 DOI: 10.3390/biology11050667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 04/16/2022] [Accepted: 04/20/2022] [Indexed: 11/17/2022]
Abstract
Chronic wasting disease (CWD) is a contagious, fatal, neurodegenerative prion disease of cervids. The expanding geographical range and rising prevalence of CWD are increasing the risk of pathogen transfer and spillover of CWD to non-cervid sympatric species. As beavers have close contact with environmental and food sources of CWD infectivity, we hypothesized that they may be susceptible to CWD prions. We evaluated the susceptibility of beavers to prion diseases by challenging transgenic mice expressing beaver prion protein (tgBeaver) with five strains of CWD, four isolates of rodent-adapted prions and one strain of Creutzfeldt-Jakob disease. All CWD strains transmitted to the tgBeaver mice, with attack rates highest from moose CWD and the 116AG and H95+ strains of deer CWD. Mouse-, rat-, and especially hamster-adapted prions were also transmitted with complete attack rates and short incubation periods. We conclude that the beaver prion protein is an excellent substrate for sustaining prion replication and that beavers are at risk for CWD pathogen transfer and spillover.
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7
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Wagner K, Pierce R, Gordon E, Hay A, Lessard A, Telling GC, Ballard JR, Moreno JA, Zabel MD. Tissue-specific biochemical differences between chronic wasting disease prions isolated from free-ranging white-tailed deer (Odocoileus virginianus). J Biol Chem 2022; 298:101834. [PMID: 35304100 PMCID: PMC9019250 DOI: 10.1016/j.jbc.2022.101834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Revised: 03/08/2022] [Accepted: 03/10/2022] [Indexed: 01/21/2023] Open
Abstract
Chronic wasting disease (CWD) is an invariably fatal prion disease affecting cervid species worldwide. Prions can manifest as distinct strains that can influence disease pathology and transmission. CWD is profoundly lymphotropic, and most infected cervids likely shed peripheral prions replicated in lymphoid organs. However, CWD is a neurodegenerative disease, and most research on prion strains has focused on neurogenic prions. Thus, a knowledge gap exists comparing neurogenic prions to lymphogenic prions. In this study, we compared prions from the obex and lymph nodes of naturally exposed white-tailed deer to identify potential biochemical strain differences. Here, we report biochemical evidence of strain differences between the brain and lymph node from these animals. Conformational stability assays, glycoform ratio analyses, and immunoreactivity scanning across the structured domain of the prion protein that refolds into the amyloid aggregate of the infectious prion reveal significantly more structural and glycoform variation in lymphogenic prions than neurogenic prions. Surprisingly, we observed greater biochemical differences among neurogenic prions than lymphogenic prions across individuals. We propose that the lymphoreticular system propagates a diverse array of prions from which the brain selects a more restricted pool of prions that may be quite different than those from another individual of the same species. Future work should examine the biological and zoonotic impact of these biochemical differences and examine more cervids from multiple locations to determine if these differences are conserved across species and locations.
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Affiliation(s)
- Kaitlyn Wagner
- Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Robyn Pierce
- Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Elizabeth Gordon
- Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Arielle Hay
- Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Avery Lessard
- Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Glenn C. Telling
- Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Jennifer R. Ballard
- Research Division, Arkansas Game and Fish Commission, Little Rock, Arkansas, USA
| | - Julie A. Moreno
- Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,Department of Environmental and Radiological Health Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA
| | - Mark D. Zabel
- Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, USA,For correspondence: Mark D. Zabel
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8
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Kincaid AE. The Role of the Nasal Cavity in the Pathogenesis of Prion Diseases. Viruses 2021; 13:v13112287. [PMID: 34835094 PMCID: PMC8621399 DOI: 10.3390/v13112287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 11/09/2021] [Accepted: 11/11/2021] [Indexed: 11/16/2022] Open
Abstract
Prion diseases, or transmissible spongiform encephalopathies (TSEs), are a class of fatal neurodegenerative diseases caused by the entry and spread of infectious prion proteins (PrPSc) in the central nervous system (CNS). These diseases are endemic to certain mammalian animal species that use their sense of smell for a variety of purposes and therefore expose their nasal cavity (NC) to PrPSc in the environment. Prion diseases that affect humans are either inherited due to a mutation of the gene that encodes the prion protein, acquired by exposure to contaminated tissues or medical devices, or develop without a known cause (referred to as sporadic). The purpose of this review is to identify components of the NC that are involved in prion transport and to summarize the evidence that the NC serves as a route of entry (centripetal spread) and/or a source of shedding (centrifugal spread) of PrPSc, and thus plays a role in the pathogenesis of the TSEs.
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Affiliation(s)
- Anthony E Kincaid
- Departments of Pharmacy Sciences and Medical Microbiology and Immunology, Creighton University, 2500 California Plaza, Omaha, NE 68178, USA
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9
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Kincheloe JM, Horn-Delzer AR, Makau DN, Wells SJ. Chronic Wasting Disease Transmission Risk Assessment for Farmed Cervids in Minnesota and Wisconsin. Viruses 2021; 13:v13081586. [PMID: 34452450 PMCID: PMC8402894 DOI: 10.3390/v13081586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/27/2021] [Accepted: 07/29/2021] [Indexed: 11/22/2022] Open
Abstract
CWD (chronic wasting disease) has emerged as one of the most important diseases of cervids and continues to adversely affect farmed and wild cervid populations, despite control and preventive measures. This study aims to use the current scientific understanding of CWD transmission and knowledge of farmed cervid operations to conduct a qualitative risk assessment for CWD transmission to cervid farms and, applying this risk assessment, systematically describe the CWD transmission risks experienced by CWD-positive farmed cervid operations in Minnesota and Wisconsin. A systematic review of literature related to CWD transmission informed our criteria to stratify CWD transmission risks to cervid operations into high-risk low uncertainty, moderate-risk high uncertainty, and negligible-risk low uncertainty categories. Case data from 34 CWD-positive farmed cervid operations in Minnesota and Wisconsin from 2002 to January 2019 were categorized by transmission risks exposure and evaluated for trends. The majority of case farms recorded high transmission risks (56%), which were likely sources of CWD, but many (44%) had only moderate or negligible transmission risks, including most of the herds (62%) detected since 2012. The presence of CWD-positive cervid farms with only moderate or low CWD transmission risks necessitates further investigation of these risks to inform effective control measures.
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Affiliation(s)
- James M. Kincheloe
- Center for Science in the Public Interest, 1220 L St. N.W., Suite 300, Washington, DC 20005, USA
- Department of Veterinary Population Medicine, University of Minnesota, 225 Vet Med Ctr, 1365 Gortner Avenue, St. Paul, MN 55108, USA; (D.N.M.); (S.J.W.)
- Correspondence:
| | - Amy R. Horn-Delzer
- Wisconsin Department of Agriculture, Trade, and Consumer Protection, 2811 Agriculture Drive, Madison, WI 53708, USA;
| | - Dennis N. Makau
- Department of Veterinary Population Medicine, University of Minnesota, 225 Vet Med Ctr, 1365 Gortner Avenue, St. Paul, MN 55108, USA; (D.N.M.); (S.J.W.)
| | - Scott J. Wells
- Department of Veterinary Population Medicine, University of Minnesota, 225 Vet Med Ctr, 1365 Gortner Avenue, St. Paul, MN 55108, USA; (D.N.M.); (S.J.W.)
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10
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Booth CJ, Lichtenberg SS, Chappell RJ, Pedersen JA. Chemical Inactivation of Prions Is Altered by Binding to the Soil Mineral Montmorillonite. ACS Infect Dis 2021; 7:859-870. [PMID: 33787209 DOI: 10.1021/acsinfecdis.0c00860] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Environmental routes of transmission contribute to the spread of the prion diseases chronic wasting disease of deer and elk and scrapie of sheep and goats. Prions can persist in soils and other environmental matrices and remain infectious for years. Prions bind avidly to the common soil mineral montmorillonite, and such binding can dramatically increase oral disease transmission. Decontamination of soil in captive facilities and natural habitats requires inactivation agents that are effective when prions are bound to soil microparticles. Here, we investigate the inactivation of free and montmorillonite-bound prions with sodium hydroxide, acidic pH, Environ LpH, and sodium hypochlorite. Immunoblotting and bioassays confirm that sodium hydroxide and sodium hypochlorite are effective for prion deactivation, although montmorillonite appears to reduce the efficacy of hypochlorite. Acidic conditions slightly reduce prion infectivity, and the acidic phenolic disinfectant Environ LpH produces slight reductions in infectivity and immunoreactivity. The extent to which the association with montmorillonite protects prions from chemical inactivation appears influenced by the effect of chemical agents on the clay structure and surface pH. When clay morphology remains relatively unaltered, as when exposed to hypochlorite, montmorillonite-bound prions appear to be protected from inactivation. In contrast, when the clay structure is substantially transformed, as when exposed to high concentrations of sodium hydroxide, the attachment to montmorillonite does not slow degradation. A reduction in surface pH appears to cause slight disruptions in clay structure, which enhances degradation under these conditions. We expect our findings will aid the development of remediation approaches for successful decontamination of prion-contaminated sites.
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Affiliation(s)
- Clarissa J. Booth
- Molecular and Environmental Toxicology Center, University of Wisconsin, Madison, Wisconsin 53706, United States
| | | | - Richard J. Chappell
- Department of Biostatistics & Medical Informatics and Department of Statistics, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Joel A. Pedersen
- Molecular and Environmental Toxicology Center, University of Wisconsin, Madison, Wisconsin 53706, United States
- Department of Soil Science, University of Wisconsin, Madison, Wisconsin 53706, United States
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11
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Classical and Atypical Scrapie in Sheep and Goats. Review on the Etiology, Genetic Factors, Pathogenesis, Diagnosis, and Control Measures of Both Diseases. Animals (Basel) 2021; 11:ani11030691. [PMID: 33806658 PMCID: PMC7999988 DOI: 10.3390/ani11030691] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/23/2021] [Accepted: 02/25/2021] [Indexed: 12/31/2022] Open
Abstract
Prion diseases, such as scrapie, are neurodegenerative diseases with a fatal outcome, caused by a conformational change of the cellular prion protein (PrPC), originating with the pathogenic form (PrPSc). Classical scrapie in small ruminants is the paradigm of prion diseases, as it was the first transmissible spongiform encephalopathy (TSE) described and is the most studied. It is necessary to understand the etiological properties, the relevance of the transmission pathways, the infectivity of the tissues, and how we can improve the detection of the prion protein to encourage detection of the disease. The aim of this review is to perform an overview of classical and atypical scrapie disease in sheep and goats, detailing those special issues of the disease, such as genetic factors, diagnostic procedures, and surveillance approaches carried out in the European Union with the objective of controlling the dissemination of scrapie disease.
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12
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Abstract
Chronic wasting disease (CWD) is an emerging and fatal contagious prion disease that affects cervids, including mule deer, white-tailed deer, black-tailed deer, red deer reindeer, elk, and moose. CWD prions are widely distributed throughout the bodies of CWD-infected animals and are found in the nervous system, lymphoid tissues, muscle, blood, urine, feces, and antler velvet. The mechanism of CWD transmission in natural settings is unknown. Potential mechanisms of transmission include horizontal, maternal, or environmental routes. Due to the presence of prions in the blood of CWD-infected animals, the potential exists for invertebrates that feed on mammalian blood to contribute to the transmission of CWD. The geographic range of the Rocky Mountain Wood tick, Dermancentor andersoni, overlaps with CWD throughout the northwest United States and southwest Canada, raising the possibility that D. andersoni parasitization of cervids may be involved in CWD transmission. We investigated this possibility by examining the blood meal of D. andersoni that fed upon prion-infected hamsters for the presence of prion infectivity by animal bioassay. None of the hamsters inoculated with a D. andersoni blood meal that had been ingested from prion-infected hamsters developed clinical signs of prion disease or had evidence for a subclinical prion infection. Overall, the data do not demonstrate a role for D. andersoni in the transmission of prion disease.IMPORTANCE Chronic wasting disease (CWD) is an emerging prion disease that affects cervids, including mule deer, white-tailed deer, black-tailed deer, red deer reindeer, elk, and moose. The mechanism of CWD transmission in unknown. Due to the presence of prions in the blood of CWD-infected animals, it is possible for invertebrates that feed on cervid blood to contribute to the transmission of CWD. We examined the blood meal of D. andersoni, a tick with a similar geographic range as cervids, that fed upon prion-infected hamsters for the presence of prion infectivity by animal bioassay. None of the D. andersoni blood meals that had been ingested from prion-infected hamsters yielded evidence of prion infection. Overall, the data do not support a role of D. andersoni in the transmission of prion disease.
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13
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Denkers ND, Hoover CE, Davenport KA, Henderson DM, McNulty EE, Nalls AV, Mathiason CK, Hoover EA. Very low oral exposure to prions of brain or saliva origin can transmit chronic wasting disease. PLoS One 2020; 15:e0237410. [PMID: 32817706 PMCID: PMC7446902 DOI: 10.1371/journal.pone.0237410] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 07/24/2020] [Indexed: 11/19/2022] Open
Abstract
The minimum infectious dose required to induce CWD infection in cervids remains unknown, as does whether peripherally shed prions and/or multiple low dose exposures are important factors in CWD transmission. With the goal of better understand CWD infection in nature, we studied oral exposures of deer to very low doses of CWD prions and also examined whether the frequency of exposure or prion source may influence infection and pathogenesis. We orally inoculated white-tailed deer with either single or multiple divided doses of prions of brain or saliva origin and monitored infection by serial longitudinal tissue biopsies spanning over two years. We report that oral exposure to as little as 300 nanograms (ng) of CWD-positive brain or to saliva containing seeding activity equivalent to 300 ng of CWD-positive brain, were sufficient to transmit CWD disease. This was true whether the inoculum was administered as a single bolus or divided as three weekly 100 ng exposures. However, when the 300 ng total dose was apportioned as 10, 30 ng doses delivered over 12 weeks, no infection occurred. While low-dose exposures to prions of brain or saliva origin prolonged the time from inoculation to first detection of infection, once infection was established, we observed no differences in disease pathogenesis. These studies suggest that the CWD minimum infectious dose approximates 100 to 300 ng CWD-positive brain (or saliva equivalent), and that CWD infection appears to conform more with a threshold than a cumulative dose dynamic.
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Affiliation(s)
- Nathaniel D. Denkers
- Department of Microbiology, Immunology, and Pathology, Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Clare E. Hoover
- AstraZeneca Inc., Waltham, Massachusetts, United States of America
| | - Kristen A. Davenport
- Department of Biochemistry, School of Medicine, University of Utah, Salt Lake City, Utah, United States of America
| | - Davin M. Henderson
- Department of Microbiology, Immunology, and Pathology, Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Erin E. McNulty
- Department of Microbiology, Immunology, and Pathology, Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Amy V. Nalls
- Department of Microbiology, Immunology, and Pathology, Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Candace K. Mathiason
- Department of Microbiology, Immunology, and Pathology, Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
| | - Edward A. Hoover
- Department of Microbiology, Immunology, and Pathology, Prion Research Center, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado, United States of America
- * E-mail:
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PARTIAL PROTECTION IN BALB/C HOUSE MICE ( MUS MUSCULUS) AND ROCKY MOUNTAIN ELK ( CERVUS CANADENSIS) AFTER VACCINATION WITH A KILLED, MUCOSALLY DELIVERED BRUCELLA ABORTUS VACCINE. J Wildl Dis 2019. [PMID: 31009310 DOI: 10.7589/2018-08-190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Brucellosis, caused by Brucella abortus, has been eliminated from livestock in the US. Remaining wildlife reservoirs are the bison (Bison bison) and elk (Cervus canadensis) populations in Yellowstone National Park and the surrounding area, from which there is periodic exposure and transmission to surrounding livestock herds. Elk account for nearly all of the livestock exposure, and the infection appears to be expanding in the elk population. Currently, there are no known effective vaccines for brucellosis in elk. We conducted three experiments to evaluate the efficacy and practicality of delivering a killed B. abortus vaccine compounded with montmorillonite clay as a carrying agent to oral, nasal, and conjunctival mucosa. The first study, conducted in laboratory mice (Mus musculus), demonstrated protection against infection equal to that produced by the currently approved cattle (Bos taurus) vaccine RB51. The second experiment, conducted as a pilot study in a small sample of elk, demonstrated partial protection against B. abortus infection. Results of the third experiment showed that elk consumed the majority of a surrogate vaccine compounded with montmorillonite mixed in hay with oral, nasal, conjunctival, and gastrointestinal exposure to the vaccine. These results suggest that multiple exposures to a mucosally delivered vaccine may provide an effective method of vaccinating wildlife.
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15
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Ellis CK, Volker SF, Griffin DL, VerCauteren KC, Nichols TA. Use of faecal volatile organic compound analysis for ante-mortem discrimination between CWD-positive, -negative exposed, and -known negative white-tailed deer (Odocoileus virginianus). Prion 2019; 13:94-105. [PMID: 31032718 PMCID: PMC7000150 DOI: 10.1080/19336896.2019.1607462] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 03/26/2019] [Accepted: 04/04/2019] [Indexed: 12/21/2022] Open
Abstract
Chronic wasting disease (CWD) is a naturally occurring infectious, fatal, transmissible spongiform encephalopathy of cervids. Currently, disease confirmation relies on post-mortem detection of infectious prions in the medial retropharyngeal lymph nodes or obex in the brain via immunohistochemistry (IHC). Detection of CWD in living animals using this method is impractical, and IHC and other experimental assays are not reliable in detecting low concentrations of prion present in biofluids or faeces. Here, we evaluate the capability of faecal volatile organic compound analysis to discriminate between CWD-positive and -exposed white-tailed deer located at two positive cervid farms, and two groups of CWD-negative deer from two separate disease-free farms.
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Affiliation(s)
- Christine K. Ellis
- Feral Swine Project, USDA-APHIS-WS-National Wildlife Research Center, Fort Collins, CO, USA
| | - Steven F. Volker
- Analytical Chemistry Department, USDA-APHIS-WS-National Wildlife Research Center, Fort Collins, CO, USA
| | - Doreen L. Griffin
- BioLaboratories, USDA-APHIS-WS-National Wildlife Research Center, Fort Collins, CO, USA
| | - Kurt C. VerCauteren
- Feral Swine Project, USDA-APHIS-WS-National Wildlife Research Center, Fort Collins, CO, USA
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16
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Kuznetsova A, Cullingham C, McKenzie D, Aiken JM. Soil humic acids degrade CWD prions and reduce infectivity. PLoS Pathog 2018; 14:e1007414. [PMID: 30496301 PMCID: PMC6264147 DOI: 10.1371/journal.ppat.1007414] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/17/2018] [Indexed: 12/25/2022] Open
Abstract
Chronic wasting disease (CWD), an environmentally transmissible, fatal prion disease is endemic in North America, present in South Korea and has recently been confirmed in northern Europe. The expanding geographic range of this contagious disease of free-ranging deer, moose, elk and reindeer has resulted in increasing levels of prion infectivity in the environment. Soils are involved in CWD horizontal transmission, acting as an environmental reservoir, and soil mineral and organic compounds have the ability to bind prions. Upper horizons of soils are usually enriched with soil organic matter (SOM), however, the role of SOM in prion conservation and mobility remains unclear. In this study, we show that incubation of PrPCWD with humic acids (HA), a major SOM compound, affects both the molecular weight and recovery of PrPCWD. Detection of PrPCWD is reduced as HA concentration increases. Native HA extracted from pristine soils also reduces or entirely eliminates PrPCWD signal. Incubation of CWD prions with HA significantly increased incubation periods in tgElk mice demonstrating that HA can reduce CWD infectivity. Chronic wasting disease (CWD) is a contagious prion disease affecting several species of captive and wild cervids. Environmental prion contamination plays a major role in increasing incidence of CWD, with CWD infectivity being released into the environment by decaying carcasses, or shedding of biological fluids including urine, feces, and saliva. Horizontal transmission of CWD involves soils as an environmental reservoir of infectivity. Here, we tested the role of a soil organic matter compound, humic acid, for its ability to bind CWD prions and impact infectivity. A wide range of humic acid concentrations were examined representing the extensive spectrum of humic acid levels present in native soils. We found that incubation of CWD prions with high concentrations of humic acids (>2.5 g L-1) decreases the both CWD-prion signal and infectivity, whereas lower levels of humic acids did not significantly impact protein stability or infectivity. Our study provides new insights into soil-prion interactions, prions persistence in soil, and their bioavailability to grazing animals.
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Affiliation(s)
- Alsu Kuznetsova
- Agricultural, Life and Environmental Sciences Faculty, University of Alberta, Edmonton, AB, Canada
| | | | - Debbie McKenzie
- Faculty of Science, University of Alberta, Edmonton, AB, Canada
| | - Judd M. Aiken
- Agricultural, Life and Environmental Sciences Faculty, University of Alberta, Edmonton, AB, Canada
- * E-mail:
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17
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Plummer IH, Johnson CJ, Chesney AR, Pedersen JA, Samuel MD. Mineral licks as environmental reservoirs of chronic wasting disease prions. PLoS One 2018; 13:e0196745. [PMID: 29719000 PMCID: PMC5931637 DOI: 10.1371/journal.pone.0196745] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 04/18/2018] [Indexed: 12/26/2022] Open
Abstract
Chronic wasting disease (CWD) is a fatal neurodegenerative disease of deer, elk, moose, and reindeer (cervids) caused by misfolded prion proteins. The disease has been reported across North America and recently discovered in northern Europe. Transmission of CWD in wild cervid populations can occur through environmental routes, but limited ability to detect prions in environmental samples has prevented the identification of potential transmission "hot spots". We establish widespread CWD prion contamination of mineral licks used by free-ranging cervids in an enzootic area in Wisconsin, USA. We show mineral licks can serve as reservoirs of CWD prions and thus facilitate disease transmission. Furthermore, mineral licks attract livestock and other wildlife that also obtain mineral nutrients via soil and water consumption. Exposure to CWD prions at mineral licks provides potential for cross-species transmission to wildlife, domestic animals, and humans. Managing deer use of mineral licks warrants further consideration to help control outbreaks of CWD.
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Affiliation(s)
- Ian H. Plummer
- Department of Forest & Wildlife Ecology, University of Wisconsin – Madison, Madison, Wisconsin, United States of America
| | - Chad J. Johnson
- Departments of Soil Science, Chemistry, and Civil & Environmental Engineering, University of Wisconsin – Madison, Madison, Wisconsin, United States of America
| | - Alexandra R. Chesney
- Molecular and Environmental Toxicology Center, University of Wisconsin – Madison, Madison, Wisconsin, United States of America
| | - Joel A. Pedersen
- Departments of Soil Science, Chemistry, and Civil & Environmental Engineering, Molecular and Environmental Toxicology Center, University of Wisconsin – Madison, Madison, Wisconsin, United States of America
- * E-mail: (MDS); (JAP)
| | - Michael D. Samuel
- Department of Forest & Wildlife Ecology, University of Wisconsin – Madison, Madison, Wisconsin, United States of America
- * E-mail: (MDS); (JAP)
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18
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Mejía‐Salazar MF, Waldner CL, Hwang YT, Bollinger TK. Use of environmental sites by mule deer: a proxy for relative risk of chronic wasting disease exposure and transmission. Ecosphere 2018. [DOI: 10.1002/ecs2.2055] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Affiliation(s)
- María Fernanda Mejía‐Salazar
- Department of Veterinary Pathology University of Saskatchewan 52 Campus Drive Saskatoon Saskatchewan S7N 5B4 Canada
| | - Cheryl L. Waldner
- Department of Large Animal Clinical Sciences University of Saskatchewan 52 Campus Drive Saskatoon Saskatchewan S7N 5B4 Canada
| | - Yeen Ten Hwang
- Department of Veterinary Pathology University of Saskatchewan 52 Campus Drive Saskatoon Saskatchewan S7N 5B4 Canada
- Fish and Wildlife Branch Saskatchewan Ministry of Environment Regina Saskatchewan S4S 5W6 Canada
| | - Trent K. Bollinger
- Department of Veterinary Pathology University of Saskatchewan 52 Campus Drive Saskatoon Saskatchewan S7N 5B4 Canada
- Canadian Wildlife Health Cooperative (CWHC) 52 Campus Drive Saskatoon Saskatchewan S7N 5B4 Canada
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19
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Dorak SJ, Green ML, Wander MM, Ruiz MO, Buhnerkempe MG, Tian T, Novakofski JE, Mateus-Pinilla NE. Clay content and pH: soil characteristic associations with the persistent presence of chronic wasting disease in northern Illinois. Sci Rep 2017; 7:18062. [PMID: 29273783 PMCID: PMC5741720 DOI: 10.1038/s41598-017-18321-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 12/08/2017] [Indexed: 01/13/2023] Open
Abstract
Environmental reservoirs are important to infectious disease transmission and persistence, but empirical analyses are relatively few. The natural environment is a reservoir for prions that cause chronic wasting disease (CWD) and influences the risk of transmission to susceptible cervids. Soil is one environmental component demonstrated to affect prion infectivity and persistence. Here we provide the first landscape predictive model for CWD based solely on soil characteristics. We built a boosted regression tree model to predict the probability of the persistent presence of CWD in a region of northern Illinois using CWD surveillance in deer and soils data. We evaluated the outcome for possible pathways by which soil characteristics may increase the probability of CWD transmission via environmental contamination. Soil clay content and pH were the most important predictive soil characteristics of the persistent presence of CWD. The results suggest that exposure to prions in the environment is greater where percent clay is less than 18% and soil pH is greater than 6.6. These characteristics could alter availability of prions immobilized in soil and contribute to the environmental risk factors involved in the epidemiological complexity of CWD infection in natural populations of white-tailed deer.
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Affiliation(s)
- Sheena J Dorak
- Illinois Natural History Survey - Prairie Research Institute, University of Illinois Urbana-Champaign, 1816 S Oak Street, Champaign, IL, 61820, USA
| | - Michelle L Green
- Illinois Natural History Survey - Prairie Research Institute, University of Illinois Urbana-Champaign, 1816 S Oak Street, Champaign, IL, 61820, USA.,Department of Animal Sciences, University of Illinois Urbana-Champaign, 1503 S Maryland Drive, Urbana, IL, 61801, USA
| | - Michelle M Wander
- Department of Natural Resources and Environmental Sciences, University of Illinois Urbana-Champaign, 1102 S Goodwin Ave, Urbana, IL, 61801, USA
| | - Marilyn O Ruiz
- Department of Pathobiology, University of Illinois Urbana-Champaign, 2001 S Lincoln Avenue, Urbana, IL, 61802, USA
| | - Michael G Buhnerkempe
- Illinois Natural History Survey - Prairie Research Institute, University of Illinois Urbana-Champaign, 1816 S Oak Street, Champaign, IL, 61820, USA
| | - Ting Tian
- Illinois Natural History Survey - Prairie Research Institute, University of Illinois Urbana-Champaign, 1816 S Oak Street, Champaign, IL, 61820, USA
| | - Jan E Novakofski
- Department of Animal Sciences, University of Illinois Urbana-Champaign, 1503 S Maryland Drive, Urbana, IL, 61801, USA
| | - Nohra E Mateus-Pinilla
- Illinois Natural History Survey - Prairie Research Institute, University of Illinois Urbana-Champaign, 1816 S Oak Street, Champaign, IL, 61820, USA.
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20
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Giachin G, Nepravishta R, Mandaliti W, Melino S, Margon A, Scaini D, Mazzei P, Piccolo A, Legname G, Paci M, Leita L. The mechanisms of humic substances self-assembly with biological molecules: The case study of the prion protein. PLoS One 2017; 12:e0188308. [PMID: 29161325 PMCID: PMC5697873 DOI: 10.1371/journal.pone.0188308] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/04/2017] [Indexed: 12/17/2022] Open
Abstract
Humic substances (HS) are the largest constituent of soil organic matter and are considered as a key component of the terrestrial ecosystem. HS may facilitate the transport of organic and inorganic molecules, as well as the sorption interactions with environmentally relevant proteins such as prions. Prions enter the environment through shedding from live hosts, facilitating a sustained incidence of animal prion diseases such as Chronic Wasting Disease and scrapie in cervid and ovine populations, respectively. Changes in prion structure upon environmental exposure may be significant as they can affect prion infectivity and disease pathology. Despite its relevance, the mechanisms of prion interaction with HS are still not completely understood. The goal of this work is to advance a structural-level picture of the encapsulation of recombinant, non-infectious, prion protein (PrP) into different natural HS. We observed that PrP precipitation upon addition of HS is mainly driven by a mechanism of "salting-out" whereby PrP molecules are rapidly removed from the solution and aggregate in insoluble adducts with humic molecules. Importantly, this process does not alter the protein folding since insoluble PrP retains its α-helical content when in complex with HS. The observed ability of HS to promote PrP insolubilization without altering its secondary structure may have potential relevance in the context of "prion ecology". These results suggest that soil organic matter interacts with prions possibly without altering the protein structures. This may facilitate prions preservation from biotic and abiotic degradation leading to their accumulation in the environment.
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Affiliation(s)
- Gabriele Giachin
- Department of Neurosciences, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
- * E-mail: (GG); (LL)
| | - Ridvan Nepravishta
- Department of Chemical Sciences and Technologies, University of Rome “Tor Vergata”, Rome, Italy
- School of Pharmacy, East Anglia University, Norwich, United Kingdom
| | - Walter Mandaliti
- Department of Chemical Sciences and Technologies, University of Rome “Tor Vergata”, Rome, Italy
| | - Sonia Melino
- Department of Chemical Sciences and Technologies, University of Rome “Tor Vergata”, Rome, Italy
| | - Alja Margon
- CREA Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria (Council for Agricultural Research and Economics), Gorizia, Italy
| | - Denis Scaini
- Life Science Department, University of Trieste, Trieste, Italy
- ELETTRA Synchrotron Light Source, Trieste, Italy
| | - Pierluigi Mazzei
- Interdepartmental Research Centre (CERMANU), University of Naples Federico II, Napoli, Italy
| | - Alessandro Piccolo
- Interdepartmental Research Centre (CERMANU), University of Naples Federico II, Napoli, Italy
| | - Giuseppe Legname
- Department of Neurosciences, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy
- ELETTRA Synchrotron Light Source, Trieste, Italy
| | - Maurizio Paci
- Department of Chemical Sciences and Technologies, University of Rome “Tor Vergata”, Rome, Italy
| | - Liviana Leita
- CREA Consiglio per la ricerca in agricoltura e l’analisi dell’economia agraria (Council for Agricultural Research and Economics), Gorizia, Italy
- * E-mail: (GG); (LL)
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21
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Palmer MV, Cox RJ, Waters WR, Thacker TC, Whipple DL. Using White-tailed Deer ( Odocoileus virginianus) in Infectious Disease Research. JOURNAL OF THE AMERICAN ASSOCIATION FOR LABORATORY ANIMAL SCIENCE : JAALAS 2017; 56:350-360. [PMID: 28724483 PMCID: PMC5517323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/14/2017] [Accepted: 03/01/2017] [Indexed: 06/07/2023]
Abstract
Between 1940 and 2004, more than 335 emerging infectious disease events were reported in the scientific literature. The majority (60%) of these events involved zoonoses, most of which (72%) were of wildlife origin or had an epidemiologically important wildlife host. Because this trend of increasing emerging diseases likely will continue, understanding the pathogenesis, transmission, and diagnosis of these diseases in the relevant wildlife host is paramount. Achieving this goal often requires using wild animals as research subjects, which are vastly different from the traditional livestock or laboratory animals used by most universities and institutions. Using wildlife in infectious disease research presents many challenges but also provides opportunities to answer questions impossible to address by using traditional models. Cervid species, especially white-tailed deer (Odocoileus virginianus), elk (Cervus canadensis), and red deer (Cervus elaphus), are hosts or sentinels for several important pathogens, some of which are zoonotic. The long history of infectious disease research using white-tailed deer, conducted at ever-increasing levels of sophisticated biosecurity, demonstrates that this type of research can be conducted safely and that valuable insights can be gained. The greatest challenges to using wildlife in infectious disease research include animal source, facility design, nutrition, animal handling, and enrichment and other practices that both facilitate animal care and enhance animal wellbeing. The study of Mycobacterium bovis infection in white-tailed deer at the USDA's National Animal Disease Center serves to illustrate one approach to address these challenges.
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Affiliation(s)
- Mitchell V Palmer
- Infectious Bacterial Diseases of Livestock Unit, National Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Ames, Iowa;,
| | - Rebecca J Cox
- Animal Resources Unit, National Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Ames, Iowa
| | - W Ray Waters
- Infectious Bacterial Diseases of Livestock Unit, National Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Ames, Iowa
| | - Tyler C Thacker
- Infectious Bacterial Diseases of Livestock Unit, National Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Ames, Iowa
| | - Diana L Whipple
- Deputy Director Office, National Animal Disease Center, Agricultural Research Service, US Department of Agriculture, Ames, Iowa
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Abstract
Chronic wasting disease (CWD) affects cervids and is the only known prion disease readily transmitted among free-ranging wild animal populations in nature. The increasing spread and prevalence of CWD among cervid populations threaten the survival of deer and elk herds in North America, and potentially beyond. This review focuses on prion ecology, specifically that of CWD, and the current understanding of the role that the environment may play in disease propagation. We recount the discovery of CWD, discuss the role of the environment in indirect CWD transmission, and consider potentially relevant environmental reservoirs and vectors. We conclude by discussing how understanding the environmental persistence of CWD lends insight into transmission dynamics and potential management and mitigation strategies.
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23
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Shikiya RA, Langenfeld KA, Eckland TE, Trinh J, Holec SAM, Mathiason CK, Kincaid AE, Bartz JC. PrPSc formation and clearance as determinants of prion tropism. PLoS Pathog 2017; 13:e1006298. [PMID: 28355274 PMCID: PMC5386299 DOI: 10.1371/journal.ppat.1006298] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 04/10/2017] [Accepted: 03/16/2017] [Indexed: 11/19/2022] Open
Abstract
Prion strains are characterized by strain-specific differences in neuropathology but can also differ in incubation period, clinical disease, host-range and tissue tropism. The hyper (HY) and drowsy (DY) strains of hamster-adapted transmissible mink encephalopathy (TME) differ in tissue tropism and susceptibility to infection by extraneural routes of infection. Notably, DY TME is not detected in the secondary lymphoreticular system (LRS) tissues of infected hosts regardless of the route of inoculation. We found that similar to the lymphotropic strain HY TME, DY TME crosses mucosal epithelia, enters draining lymphatic vessels in underlying laminae propriae, and is transported to LRS tissues. Since DY TME causes disease once it enters the peripheral nervous system, the restriction in DY TME pathogenesis is due to its inability to establish infection in LRS tissues, not a failure of transport. To determine if LRS tissues can support DY TME formation, we performed protein misfolding cyclic amplification using DY PrPSc as the seed and spleen homogenate as the source of PrPC. We found that the spleen environment can support DY PrPSc formation, although at lower rates compared to lymphotropic strains, suggesting that the failure of DY TME to establish infection in the spleen is not due to the absence of a strain-specific conversion cofactor. Finally, we provide evidence that DY PrPSc is more susceptible to degradation when compared to PrPSc from other lymphotrophic strains. We hypothesize that the relative rates of PrPSc formation and clearance can influence prion tropism.
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Affiliation(s)
- Ronald A. Shikiya
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Katie A. Langenfeld
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Thomas E. Eckland
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Jonathan Trinh
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Sara A. M. Holec
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
| | - Candace K. Mathiason
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Anthony E. Kincaid
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
- Department of Pharmacy Science, Creighton University, Omaha, Nebraska, United States of America
| | - Jason C. Bartz
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, Nebraska, United States of America
- * E-mail:
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24
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Nichols TA, Fischer JW, Spraker TR, Kong Q, VerCauteren KC. CWD prions remain infectious after passage through the digestive system of coyotes (Canis latrans). Prion 2016; 9:367-75. [PMID: 26636258 PMCID: PMC4964857 DOI: 10.1080/19336896.2015.1086061] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Chronic wasting disease (CWD) is a geographically expanding prion disease of wild and captive cervids in North America. Disease can be transmitted directly, animal to animal, or indirectly via the environment. CWD contamination can occur residually in the environment via soil, water, and forage following deposition of bodily fluids such as urine, saliva, and feces, or by the decomposition of carcasses. Recent work has indicated that plants may even take up prions into the stems and leaves. When a carcass or gut pile is present in the environment, a large number of avian and mammalian species visit and consume the carrion. Additionally, predators like coyotes, likely select for disease-compromised cervids. Natural cross-species CWD transmission has not been documented, however, passage of infectious prion material has been observed in the feces of crows. In this study we evaluated the ability of CWD-infected brain material to pass through the gastrointestinal tract of coyotes (Canis latrans) following oral ingestion, and be infectious in a cervidized transgenic mouse model. Results from this study indicate that coyotes can pass infectious prions via their feces for at least 3 days post ingestion, demonstrating that mammalian scavengers could contribute to the translocation and contamination of CWD in the environment.
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Affiliation(s)
- Tracy A Nichols
- a National Wildlife Research Center; United States Department of Agriculture ; Animal and Plant Health Inspection Service; Wildlife Services ; Fort Collins , CO USA
| | - Justin W Fischer
- a National Wildlife Research Center; United States Department of Agriculture ; Animal and Plant Health Inspection Service; Wildlife Services ; Fort Collins , CO USA
| | - Terry R Spraker
- b Colorado State University Diagnostic Laboratory; College of Veterinary Medicine; Colorado State University ; Fort Collins , CO USA.,c Department of Microbiology, Immunology and Pathology ; College of Veterinary Medicine and Biomedical Sciences; Colorado State University Prion Research Center ; Fort Collins , CO USA
| | - Qingzhong Kong
- d National Prion Disease Pathology Surveillance Center; Institute of Pathology; Case Western Reserve University ; Cleveland , OH USA
| | - Kurt C VerCauteren
- a National Wildlife Research Center; United States Department of Agriculture ; Animal and Plant Health Inspection Service; Wildlife Services ; Fort Collins , CO USA
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25
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Specificity, Size, and Frequency of Spaces That Characterize the Mechanism of Bulk Transepithelial Transport of Prions in the Nasal Cavities of Hamsters and Mice. J Virol 2016; 90:8293-301. [PMID: 27384659 DOI: 10.1128/jvi.01103-16] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 06/28/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Inhalation of infected brain homogenate results in transepithelial transport of prions across the nasal mucosa of hamsters, some of which occurs rapidly in relatively large amounts between cells (A. E. Kincaid, K. F. Hudson, M. W. Richey, and J. C. Bartz, J. Virol 86:12731-12740, 2012, doi:http://dx.doi.org/10.1128/JVI.01930-12). Bulk transepithelial transport in the nasal cavity has not been studied to date. In the present study, we characterized the frequency, size, and specificity of the intercellular spaces that mediate the bulk transport of inhaled prions between cells of mice or hamsters following extranasal inoculation with mock-infected brain homogenate, different strains of prion-infected brain homogenate, or brain homogenate mixed with India ink. Infected or mock-infected inoculum was identified within lymphatic vessels of the lamina propria and in spaces of >5 μm between a small number of cells of the nasal mucosa in >90% of animals from 5 to 60 min after inhalation. The width of the spaces between cells, the amount of the inoculum within the lumen of lymphatic vessels, and the timing of the transport indicate that this type of transport was taking place through preexisting spaces in the nasal cavity that were orders of magnitude wider than what is normally reported for paracellular transport. The indiscriminate rapid bulk transport of brain homogenate in the nasal cavity results in immediate entry into nasal cavity lymphatics following inhalation. This novel mechanism may underlie the recent report of the early detection of prions in blood following inhalation and has implications for horizontal prion transmission. IMPORTANCE The results of these studies demonstrate that the nasal mucosa of mice and hamsters is not an absolute anatomical barrier to inhaled prion-infected or uninfected brain homogenate. Relatively large amounts of infected and uninfected brain homogenate rapidly cross the nasal mucosa and enter the lumen of lymphatic vessels following inhalation. These bulk transepithelial transport events were relatively rare but present in >90% of animals 5 to 60 min following inhalation. This novel mechanism of bulk transepithelial transport was seen in experimental and control hamsters and mice, indicating that it was not species specific or in response to prion exposure. The indiscriminate bulk intercellular transport of inhaled pathogens across the nasal mucosa followed by entry into the lymphatic system may be a mechanism that underlies the entry and spread of other toxins and pathogens in olfactory system-driven animals.
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Holcomb KM, Galloway NL, Mathiason CK, Antolin MF. Intra-host mathematical model of chronic wasting disease dynamics in deer (Odocoileus). Prion 2016; 10:377-390. [PMID: 27537196 PMCID: PMC5105936 DOI: 10.1080/19336896.2016.1189054] [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] [Indexed: 11/09/2022] Open
Abstract
Bioassays of native cervid hosts have established the presence of infectious chronic wasting disease (CWD) prions in saliva, blood, urine, and feces of clinically diseased and pre-clinical infected deer. The intra-host trafficking of prions from the time of initial infection to shedding has been less well defined. We created a discrete-time compartmentalized model to simulate the misfolding catalysis, trafficking, and shedding of infectious prions throughout the organ systems of CWD-infected cervids. Using parameter values derived from experimental infections of North American deer (Odocoileus spp.), the exponential-based model predicts prion deposition over time with: 1) nervous tissues containing the highest deposition of prions at 20 months post-infection and 2) excreted fluids containing low levels of prions throughout infection with the highest numbers of prions predicted to be shed in saliva and feces (as high as 10 lethal doses (1.34 × 1029 prions) in 11–15 months). These findings are comparable to prion deposition described in literature as assayed by conventional and ultrasensitive amplification assays. The comparison of our model to published data suggests that highly sensitive assays (sPMCA, RT-QuIC, and bioassay) are appropriate for early prion detection in bodily fluids and secretions. The model provides a view of intra-host prion catalysis leading to pre-clinical shedding and provides a framework for continued development of antemortem diagnostic methods.
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Affiliation(s)
- Karen M Holcomb
- a Department of Biology , Colorado State University , Fort Collins , CO , USA
| | - Nathan L Galloway
- a Department of Biology , Colorado State University , Fort Collins , CO , USA
| | - Candace K Mathiason
- b Department of Microbiology , Immunology, and Pathology, Colorado State University , Fort Collins , CO , USA
| | - Michael F Antolin
- a Department of Biology , Colorado State University , Fort Collins , CO , USA
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Gough KC, Baker CA, Simmons HA, Hawkins SA, Maddison BC. Circulation of prions within dust on a scrapie affected farm. Vet Res 2015; 46:40. [PMID: 25889731 PMCID: PMC4397813 DOI: 10.1186/s13567-015-0176-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2014] [Accepted: 03/30/2015] [Indexed: 11/14/2022] Open
Abstract
Prion diseases are fatal neurological disorders that affect humans and animals. Scrapie of sheep/goats and Chronic Wasting Disease (CWD) of deer/elk are contagious prion diseases where environmental reservoirs have a direct link to the transmission of disease. Using protein misfolding cyclic amplification we demonstrate that scrapie PrPSc can be detected within circulating dusts that are present on a farm that is naturally contaminated with sheep scrapie. The presence of infectious scrapie within airborne dusts may represent a possible route of infection and illustrates the difficulties that may be associated with the effective decontamination of such scrapie affected premises.
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Affiliation(s)
- Kevin C Gough
- School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington, Loughborough, Leicestershire, LE12 5RD, UK.
| | - Claire A Baker
- ADAS UK, School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington, Loughborough, Leicestershire, LE12 5RD, UK.
| | - Hugh A Simmons
- Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK.
| | - Steve A Hawkins
- Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, UK.
| | - Ben C Maddison
- ADAS UK, School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington, Loughborough, Leicestershire, LE12 5RD, UK.
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Kuznetsova A, McKenzie D, Banser P, Siddique T, Aiken JM. Potential role of soil properties in the spread of CWD in western Canada. Prion 2015; 8:92-9. [PMID: 24618673 DOI: 10.4161/pri.28467] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Chronic wasting disease (CWD) is a horizontally transmissible prion disease of free ranging deer, elk and moose. Recent experimental transmission studies indicate caribou are also susceptible to the disease. CWD is present in southeast Alberta and southern Saskatchewan. This CWD-endemic region is expanding, threatening Manitoba and areas of northern Alberta and Saskatchewan, home to caribou. Soil can serve as a stable reservoir for infectious prion proteins; prions bound to soil particles remain infectious in the soils for many years. Soils of western Canada are very diverse and the ability of CWD prions to bind different soils and the impact of this interaction on infectivity is not known. In general, clay-rich soils may bind prions avidly and enhance their infectivity comparable to pure clay mineral montmorillonite. Organic components of soils are also diverse and not well characterized, yet can impact prion-soil interaction. Other important contributing factors include soil pH, composition of soil solution and amount of metals (metal oxides). In this review, properties of soils of the CWD-endemic region in western Canada with its surrounding terrestrial environment are described and used to predict bioavailability and, thus, potential spread of CWD. The major soils in the CWD-endemic region of Alberta and Saskatchewan are Chernozems, present in 60% of the total area; they are generally similar in texture, clay mineralogy and soil organic matter content, and can be characterized as clay loamy, montmorillonite (smectite) soils with 6-10% organic carbon. The greatest risk of CWD spread in western Canada relates to clay loamy, montmorillonite soils with humus horizon. Such soils are predominant in the southern region of Alberta, Saskatchewan and Manitoba, but are less common in northern regions of the provinces where quartz-illite sandy soils with low amount of humus prevail.
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Prion amplification and hierarchical Bayesian modeling refine detection of prion infection. Sci Rep 2015; 5:8358. [PMID: 25665713 PMCID: PMC5389033 DOI: 10.1038/srep08358] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 01/19/2015] [Indexed: 12/05/2022] Open
Abstract
Prions are unique infectious agents that replicate without a genome and cause neurodegenerative diseases that include chronic wasting disease (CWD) of cervids. Immunohistochemistry (IHC) is currently considered the gold standard for diagnosis of a prion infection but may be insensitive to early or sub-clinical CWD that are important to understanding CWD transmission and ecology. We assessed the potential of serial protein misfolding cyclic amplification (sPMCA) to improve detection of CWD prior to the onset of clinical signs. We analyzed tissue samples from free-ranging Rocky Mountain elk (Cervus elaphus nelsoni) and used hierarchical Bayesian analysis to estimate the specificity and sensitivity of IHC and sPMCA conditional on simultaneously estimated disease states. Sensitivity estimates were higher for sPMCA (99.51%, credible interval (CI) 97.15–100%) than IHC of obex (brain stem, 76.56%, CI 57.00–91.46%) or retropharyngeal lymph node (90.06%, CI 74.13–98.70%) tissues, or both (98.99%, CI 90.01–100%). Our hierarchical Bayesian model predicts the prevalence of prion infection in this elk population to be 18.90% (CI 15.50–32.72%), compared to previous estimates of 12.90%. Our data reveal a previously unidentified sub-clinical prion-positive portion of the elk population that could represent silent carriers capable of significantly impacting CWD ecology.
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Lavelle MJ, Phillips GE, Fischer JW, Burke PW, Seward NW, Stahl RS, Nichols TA, Wunder BA, VerCauteren KC. Mineral licks: motivational factors for visitation and accompanying disease risk at communal use sites of elk and deer. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2014; 36:1049-1061. [PMID: 24711146 DOI: 10.1007/s10653-014-9600-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Accepted: 03/15/2014] [Indexed: 06/03/2023]
Abstract
Free-ranging cervids acquire most of their essential minerals through forage consumption, though occasionally seek other sources to account for seasonal mineral deficiencies. Mineral sources occur as natural geological deposits (i.e., licks) or as anthropogenic mineral supplements. In both scenarios, these sources commonly serve as focal sites for visitation. We monitored 11 licks in Rocky Mountain National Park, north-central Colorado, using trail cameras to quantify daily visitation indices (DVI) and soil consumption indices (SCI) for Rocky Mountain elk (Cervus elaphus) and mule deer (Odocoileus hemionus) during summer 2006 and documented elk, mule deer, and moose (Alces alces) visiting licks. Additionally, soil samples were collected, and mineral concentrations were compared to discern levels that explain rates of visitation. Relationships between response variables; DVI and SCI, and explanatory variables; elevation class, moisture class, period of study, and concentrations of minerals were examined. We found that DVI and SCI were greatest at two wet, low-elevation licks exhibiting relatively high concentrations of manganese and sodium. Because cervids are known to seek Na from soils, we suggest our observed association of Mn with DVI and SCI was a likely consequence of deer and elk seeking supplemental dietary Na. Additionally, highly utilized licks such as these provide an area of concentrated cervid occupation and interaction, thus increasing risk for environmental transmission of infectious pathogens such as chronic wasting disease, which has been shown to be shed in the saliva, urine, and feces of infected cervids.
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Affiliation(s)
- Michael J Lavelle
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, 4101 LaPorte Avenue, Fort Collins, CO, 80521-2154, USA,
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Saá P, Cervenakova L. Protein misfolding cyclic amplification (PMCA): Current status and future directions. Virus Res 2014; 207:47-61. [PMID: 25445341 DOI: 10.1016/j.virusres.2014.11.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 10/05/2014] [Accepted: 11/06/2014] [Indexed: 12/26/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs) most commonly known as prion diseases are invariably fatal neurological disorders that affect humans and animals. These disorders differ from other neurodegenerative conformational diseases caused by the accumulation in the brain of misfolded proteins, sometimes with amyloid properties, in their ability to infect susceptible species by various routes. While the infectious properties of amyloidogenic proteins, other than misfolded prion protein (PrP(TSE)), are currently under scrutiny, their potential to transmit from cell to cell, one of the intrinsic properties of the prion, has been recently shown in vitro and in vivo. Over the decades, various cell culture and laboratory animal models have been developed to study TSEs. These assays have been widely used in a variety of applications but showed to be time consuming and entailed elevated costs. Novel economic and fast alternatives became available with the development of in vitro assays that are based on the property of conformationally abnormal PrP(TSE) to recruit normal cellular PrP(C) to misfold. These include the cell-free conversion assay, protein misfolding cyclic amplification (PMCA) and quaking induced conversion assay (QuIC), of which the PMCA has been the only technology shown to generate infectious prions. Moreover, it allows indefinite amplification of PrP(TSE) with strain-specific biochemical and biological properties of the original molecules and under certain conditions may give rise to new spontaneously generated prions. The method also allows addressing the species barrier phenomena and assessing possible risks of animal-to-animal and animal-to-human transmission. Additionally, its unprecedented sensitivity has made possible the detection of as little as one infectious dose of PrP(TSE) and the biochemical identification of this protein in different tissues and biological fluids, including blood, cerebral spinal fluid (CSF), semen, milk, urine and saliva during the pre-clinical and clinical phases of the disease. The mechanistic similarities between TSEs and other conformational disorders have resulted in the adaptation of the PMCA to the amplification and detection of various amyloidogenic proteins. Here we provide a compelling discussion of the different applications of this technology to the study of TSEs and other neurodegenerative diseases.
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Affiliation(s)
- Paula Saá
- Transmissible Diseases Department, American National Red Cross, Biomedical Services, Holland Laboratory, 15601 Crabbs Branch Way, Rockville, MD 20855, United States.
| | - Larisa Cervenakova
- Transmissible Diseases Department, American National Red Cross, Biomedical Services, Holland Laboratory, 15601 Crabbs Branch Way, Rockville, MD 20855, United States
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Hawkins SAC, Simmons HA, Gough KC, Maddison BC. Persistence of ovine scrapie infectivity in a farm environment following cleaning and decontamination. Vet Rec 2014; 176:99. [PMID: 25362003 DOI: 10.1136/vr.102743] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Scrapie of sheep/goats and chronic wasting disease of deer/elk are contagious prion diseases where environmental reservoirs are directly implicated in the transmission of disease. In this study, the effectiveness of recommended scrapie farm decontamination regimens was evaluated by a sheep bioassay using buildings naturally contaminated with scrapie. Pens within a farm building were treated with either 20,000 parts per million free chorine solution for one hour or were treated with the same but were followed by painting and full re-galvanisation or replacement of metalwork within the pen. Scrapie susceptible lambs of the PRNP genotype VRQ/VRQ were reared within these pens and their scrapie status was monitored by recto-anal mucosa-associated lymphoid tissue. All animals became infected over an 18-month period, even in the pen that had been subject to the most stringent decontamination process. These data suggest that recommended current guidelines for the decontamination of farm buildings following outbreaks of scrapie do little to reduce the titre of infectious scrapie material and that environmental recontamination could also be an issue associated with these premises.
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Affiliation(s)
- Steve A C Hawkins
- Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Hugh A Simmons
- Animal and Plant Health Agency, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Kevin C Gough
- School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK
| | - Ben C Maddison
- ADAS UK, School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington, Loughborough, Leicestershire LE12 5RD, UK
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Prion protein interaction with soil humic substances: environmental implications. PLoS One 2014; 9:e100016. [PMID: 24937266 PMCID: PMC4061048 DOI: 10.1371/journal.pone.0100016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2013] [Accepted: 05/21/2014] [Indexed: 02/06/2023] Open
Abstract
Transmissible spongiform encephalopathies (TSE) are fatal neurodegenerative disorders caused by prions. Animal TSE include scrapie in sheep and goats, and chronic wasting disease (CWD) in cervids. Effective management of scrapie in many parts of the world, and of CWD in North American deer population is complicated by the persistence of prions in the environment. After shedding from diseased animals, prions persist in soil, withstanding biotic and abiotic degradation. As soil is a complex, multi-component system of both mineral and organic components, it is important to understand which soil compounds may interact with prions and thus contribute to disease transmission. Several studies have investigated the role of different soil minerals in prion adsorption and infectivity; we focused our attention on the interaction of soil organic components, the humic substances (HS), with recombinant prion protein (recPrP) material. We evaluated the kinetics of recPrP adsorption, providing a structural and biochemical characterization of chemical adducts using different experimental approaches. Here we show that HS act as potent anti-prion agents in prion infected neuronal cells and in the amyloid seeding assays: HS adsorb both recPrP and prions, thus sequestering them from the prion replication process. We interpreted our findings as highly relevant from an environmental point of view, as the adsorption of prions in HS may affect their availability and consequently hinder the environmental transmission of prion diseases in ruminants.
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Abstract
Individuals infected with prions succumb to brain damage, and prion infections continue to be inexorably lethal. However, many crucial steps in prion pathogenesis occur in lymphatic organs and precede invasion of the central nervous system. In the past two decades, a great deal has been learnt concerning the cellular and molecular mechanisms of prion lymphoinvasion. These properties are diagnostically useful and have, for example, facilitated preclinical diagnosis of variant Creutzfeldt-Jakob disease in the tonsils. Moreover, the early colonization of lymphoid organs can be exploited for post-exposure prophylaxis of prion infections. As stromal cells of lymphoid organs are crucial for peripheral prion infection, the dedifferentiation of these cells offers a powerful means of hindering prion spread in infected individuals. In this Review, we discuss the current knowledge of the immunobiology of prions with an emphasis on how basic discoveries might enable translational strategies.
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