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Bender H, Noyes N, Annis JL, Hitpas A, Mollnow L, Croak K, Kane S, Wagner K, Dow S, Zabel M. PrPC knockdown by liposome-siRNA-peptide complexes (LSPCs) prolongs survival and normal behavior of prion-infected mice immunotolerant to treatment. PLoS One 2019; 14:e0219995. [PMID: 31329627 PMCID: PMC6645518 DOI: 10.1371/journal.pone.0219995] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 07/05/2019] [Indexed: 11/29/2022] Open
Abstract
Prion diseases are members of neurodegenerative protein misfolding diseases (NPMDs) that include Alzheimer's, Parkinson's and Huntington diseases, amyotrophic lateral sclerosis, tauopathies, traumatic brain injuries, and chronic traumatic encephalopathies. No known therapeutics extend survival or improve quality of life of humans afflicted with prion disease. We and others developed a new approach to NPMD therapy based on reducing the amount of the normal, host-encoded protein available as substrate for misfolding into pathologic forms, using RNA interference, a catabolic pathway that decreases levels of mRNA encoding a particular protein. We developed a therapeutic delivery system consisting of small interfering RNA (siRNA) complexed to liposomes and addressed to the central nervous system using a targeting peptide derived from rabies virus glycoprotein. These liposome-siRNA-peptide complexes (LSPCs) cross the blood-brain barrier and deliver PrP siRNA to neuronal cells to decrease expression of the normal cellular prion protein, PrPC, which acts as a substrate for prion replication. Here we show that LSPCs can extend survival and improve behavior of prion-infected mice that remain immunotolerant to treatment. LSPC treatment may be a viable therapy for prion and other NPMDs that can improve the quality of life of patients at terminal disease stages.
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Affiliation(s)
- Heather Bender
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
- Department of Pharmacology, University of Colorado School of Medicine, Aurora, CO, United States of America
| | - Noelle Noyes
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
- Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, United States of America
| | - Jessica L. Annis
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Amanda Hitpas
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Luke Mollnow
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Kendra Croak
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Sarah Kane
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Kaitlyn Wagner
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Steven Dow
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
- Center for Immune and Regenerative Medicine, Department of Clinical Sciences, Colorado State University, Fort Collins, CO, United States of America
| | - Mark Zabel
- Prion Research Center, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO, United States of America
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2
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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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3
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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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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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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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Wyckoff AC, Kane S, Lockwood K, Seligman J, Michel B, Hill D, Ortega A, Mangalea MR, Telling GC, Miller MW, Vercauteren K, Zabel MD. Clay Components in Soil Dictate Environmental Stability and Bioavailability of Cervid Prions in Mice. Front Microbiol 2016; 7:1885. [PMID: 27933048 PMCID: PMC5120086 DOI: 10.3389/fmicb.2016.01885] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 11/09/2016] [Indexed: 12/20/2022] Open
Abstract
Chronic wasting disease (CWD) affects cervids and is the only known prion disease to affect free-ranging wildlife populations. CWD spread continues unabated, and exact mechanisms of its seemingly facile spread among deer and elk across landscapes in North America remain elusive. Here we confirm that naturally contaminated soil contains infectious CWD prions that can be transmitted to susceptible model organisms. We show that smectite clay content of soil potentiates prion binding capacity of different soil types from CWD endemic and non-endemic areas, likely contributing to environmental stability of bound prions. The smectite clay montmorillonite (Mte) increased prion retention and bioavailability in vivo. Trafficking experiments in live animals fed bound and unbound prions showed that mice retained significantly more Mte-bound than unbound prions. Mte promoted rapid uptake of prions from the stomach to the intestines via enterocytes and M cells, and then to macrophages and eventually CD21+ B cells in Peyer's patches and spleens. These results confirm clay components in soil as an important vector in CWD transmission at both environmental and organismal levels.
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Affiliation(s)
- A Christy Wyckoff
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | - Sarah Kane
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | - Krista Lockwood
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | - Jeff Seligman
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | - Brady Michel
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | - Dana Hill
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | - Aimee Ortega
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | - Mihnea R Mangalea
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | - Glenn C Telling
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
| | | | - Kurt Vercauteren
- National Wildlife Research Center, Wildlife Services, United States Department of Agriculture Fort Collins, CO, USA
| | - Mark D Zabel
- Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Prion Research Center at Colorado State University Fort Collins, CO, USA
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7
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Selariu A, Powers JG, Nalls A, Brandhuber M, Mayfield A, Fullaway S, Wyckoff CA, Goldmann W, Zabel MM, Wild MA, Hoover EA, Mathiason CK. In utero transmission and tissue distribution of chronic wasting disease-associated prions in free-ranging Rocky Mountain elk. J Gen Virol 2015; 96:3444-3455. [PMID: 26358706 DOI: 10.1099/jgv.0.000281] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The presence of disease-associated prions in tissues and bodily fluids of chronic wasting disease (CWD)-infected cervids has received much investigation, yet little is known about mother-to-offspring transmission of CWD. Our previous work demonstrated that mother-to-offspring transmission is efficient in an experimental setting. To address the question of relevance in a naturally exposed free-ranging population, we assessed maternal and fetal tissues derived from 19 elk dam-calf pairs collected from free-ranging Rocky Mountain elk from north-central Colorado, a known CWD endemic region. Conventional immunohistochemistry identified three of 19 CWD-positive dams, whereas a more sensitive assay [serial protein misfolding cyclic amplification (sPMCA)] detected CWD prion seeding activity (PrPCWD) in 15 of 19 dams. PrPCWD distribution in tissues was widespread, and included the central nervous system (CNS), lymphoreticular system, and reproductive, secretory, excretory and adipose tissues. Interestingly, five of 15 sPMCA-positive dams showed no evidence of PrPCWD in either CNS or lymphoreticular system, sites typically assessed in diagnosing CWD. Analysis of fetal tissues harvested from the 15 sPMCA-positive dams revealed PrPCWD in 80 % of fetuses (12 of 15), regardless of gestational stage. These findings demonstrated that PrPCWD is more abundant in peripheral tissues of CWD-exposed elk than current diagnostic methods suggest, and that transmission of prions from mother to offspring may contribute to the efficient transmission of CWD in naturally exposed cervid populations.
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Affiliation(s)
- Anca Selariu
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Jenny G Powers
- National Park Service, Biological Resources Division, 1201 Oakridge Drive, Suite 200, Fort Collins, Colorado, USA
| | - Amy Nalls
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Monica Brandhuber
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Amber Mayfield
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Stephenie Fullaway
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Christy A Wyckoff
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Wilfred Goldmann
- Roslin Institute, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Mark M Zabel
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Margaret A Wild
- National Park Service, Biological Resources Division, 1201 Oakridge Drive, Suite 200, Fort Collins, Colorado, USA
| | - Edward A Hoover
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
| | - Candace K Mathiason
- Colorado State University, Prion Research Center, Department of Microbiology, Immunology, and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, Colorado, USA
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8
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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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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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