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Reflections on Cerebellar Neuropathology in Classical Scrapie. Biomolecules 2021; 11:biom11050649. [PMID: 33924986 PMCID: PMC8146067 DOI: 10.3390/biom11050649] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 04/13/2021] [Accepted: 04/20/2021] [Indexed: 01/15/2023] Open
Abstract
In this review, the most important neuropathological changes found in the cerebella of sheep affected by classical natural scrapie are discussed. This disease is the oldest known of a group of unconventional “infections” caused by toxic prions of different origins. Scrapie is currently considered a “transmissible spongiform encephalopathy” (due to its neuropathological characteristics and its transmission), which is the paradigm of prion pathologies as well as many encephalopathies (prion-like) that present aberrant deposits of insoluble protein with neurotoxic effects due to errors in their catabolization (“misfolding protein diseases”). The study of this disease is, therefore, of great relevance. Our work data from the authors’ previous publications as well as other research in the field. The four most important types of neuropathological changes are neuron abnormalities and loss, neurogliosis, tissue vacuolization (spongiosis) and pathological or abnormal prion protein (PrP) deposits/deposition. These findings were analyzed and compared to other neuropathologies. Various aspects related to the presentation and progression of the disease, the involution of different neuronal types, the neuroglial responses and the appearance of abnormal PrP deposits are discussed. The most important points of controversy in scrapie neuropathology are presented.
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Ricci A, Allende A, Bolton D, Chemaly M, Davies R, Fernández Escámez PS, Gironés R, Herman L, Koutsoumanis K, Lindqvist R, Nørrung B, Robertson L, Ru G, Sanaa M, Skandamis P, Speybroeck N, Simmons M, Kuile BT, Threlfall J, Wahlström H, Acutis PL, Andreoletti O, Goldmann W, Langeveld J, Windig JJ, Ortiz Pelaez A, Snary E. Genetic resistance to transmissible spongiform encephalopathies (TSE) in goats. EFSA J 2017; 15:e04962. [PMID: 32625625 PMCID: PMC7010077 DOI: 10.2903/j.efsa.2017.4962] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Breeding programmes to promote resistance to classical scrapie, similar to those for sheep in existing transmissible spongiform encephalopathies (TSE) regulations, have not been established in goats. The European Commission requested a scientific opinion from EFSA on the current knowledge of genetic resistance to TSE in goats. An evaluation tool, which considers both the weight of evidence and strength of resistance to classical scrapie of alleles in the goat PRNP gene, was developed and applied to nine selected alleles of interest. Using the tool, the quality and certainty of the field and experimental data are considered robust enough to conclude that the K222, D146 and S146 alleles both confer genetic resistance against classical scrapie strains known to occur naturally in the EU goat population, with which they have been challenged both experimentally and under field conditions. The weight of evidence for K222 is greater than that currently available for the D146 and S146 alleles and for the ARR allele in sheep in 2001. Breeding for resistance can be an effective tool for controlling classical scrapie in goats and it could be an option available to member states, both at herd and population levels. There is insufficient evidence to assess the impact of K222, D146 and S146 alleles on susceptibility to atypical scrapie and bovine spongiform encephalopathy (BSE), or on health and production traits. These alleles are heterogeneously distributed across the EU Member States and goat breeds, but often at low frequencies (< 10%). Given these low frequencies, high selection pressure may have an adverse effect on genetic diversity so any breeding for resistance programmes should be developed at Member States, rather than EU level and their impact monitored, with particular attention to the potential for any negative impact in rare or small population breeds.
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Konold T, Phelan LJ, Donnachie BR, Chaplin MJ, Cawthraw S, González L. Codon 141 polymorphisms of the ovine prion protein gene affect the phenotype of classical scrapie transmitted from goats to sheep. BMC Vet Res 2017; 13:122. [PMID: 28472956 PMCID: PMC5418773 DOI: 10.1186/s12917-017-1036-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Accepted: 04/21/2017] [Indexed: 11/14/2022] Open
Abstract
Background A study to investigate transmission of classical scrapie via goat milk was carried out in sheep: firstly, lambs were challenged orally with goat scrapie brain homogenate to confirm transmission of scrapie from goats to sheep. In the second study phase, milk from scrapie-infected goats was fed to lambs. Lambs were selected according to their prion protein gene (PRNP) genotype, which was either VRQ/VRQ or ARQ/ARQ, with or without additional polymorphisms at codon 141 (FF141, LF141 or LL141) of the ovine PRNP. This report describes the clinical, pathological and molecular phenotype of goat scrapie in those sheep that progressed to clinical end-stage. Results Ten sheep (six VRQ/VRQ and four ARQ/ARQ, of which three FF141 and one LL141) challenged with one of two scrapie brain homogenates, and six pairs of sheep (ARQ, of which five LL141 and seven LF141) fed milk from six different goats, developed clinical disease, which was characterised by a pruritic (all VRQ/VRQ and LL141 sheep) or a non-pruritic form (all LF141 and FF141 sheep). Immunohistochemical (IHC) examination revealed that the pattern of intra- and extracellular accumulation of disease-associated prion protein in the brain was also dependent on PRNP polymorphisms at codon 141, which was similar in VRQ and LL141 sheep but different from LF141 and FF141 sheep. The influence of codon 141 was also seen in discriminatory Western blot (WB), with LF141 and FF141 sheep showing a bovine spongiform encephalopathy-like profile (diminished reactivity with P4 antibody) on brain tissue. However, discriminatory WB in lymphoid tissues, and IHC pattern and profile both in lymphoid and brain tissue was consistent with classical scrapie in all sheep. Conclusions This study provided further evidence that the clinical presentation and the pathological and molecular phenotypes of scrapie in sheep are influenced by PRNP polymorphisms, particularly at codon 141. Differences in the truncation of disease-associated prion protein between LL141 sheep and those carrying the F141 allele may be responsible for these observations. Electronic supplementary material The online version of this article (doi:10.1186/s12917-017-1036-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Timm Konold
- Animal Sciences Unit, Animal and Plant Health Agency Weybridge, Addlestone, UK.
| | - Laura J Phelan
- Animal Sciences Unit, Animal and Plant Health Agency Weybridge, Addlestone, UK
| | - Ben R Donnachie
- Pathology Department, Animal and Plant Health Agency Weybridge, Addlestone, UK
| | - Melanie J Chaplin
- Pathology Department, Animal and Plant Health Agency Weybridge, Addlestone, UK
| | - Saira Cawthraw
- Central Sequencing Unit, Animal and Plant Health Agency Weybridge, Addlestone, UK
| | - Lorenzo González
- Pathology Department, Animal and Plant Health Agency Lasswade, Penicuik, UK
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Deer Prion Proteins Modulate the Emergence and Adaptation of Chronic Wasting Disease Strains. J Virol 2015; 89:12362-73. [PMID: 26423950 PMCID: PMC4665243 DOI: 10.1128/jvi.02010-15] [Citation(s) in RCA: 65] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 09/23/2015] [Indexed: 12/02/2022] Open
Abstract
Transmission of chronic wasting disease (CWD) between cervids is influenced by the primary structure of the host cellular prion protein (PrPC). In white-tailed deer, PRNP alleles encode the polymorphisms Q95 G96 (wild type [wt]), Q95 S96 (referred to as the S96 allele), and H95 G96 (referred to as the H95 allele), which differentially impact CWD progression. We hypothesize that the transmission of CWD prions between deer expressing different allotypes of PrPC modifies the contagious agent affecting disease spread. To evaluate the transmission properties of CWD prions derived experimentally from deer of four PRNP genotypes (wt/wt, S96/wt, H95/wt, or H95/S96), transgenic (tg) mice expressing the wt allele (tg33) or S96 allele (tg60) were challenged with these prion agents. Passage of deer CWD prions into tg33 mice resulted in 100% attack rates, with the CWD H95/S96 prions having significantly longer incubation periods. The disease signs and neuropathological and protease-resistant prion protein (PrP-res) profiles in infected tg33 mice were similar between groups, indicating that a prion strain (Wisc-1) common to all CWD inocula was amplified. In contrast, tg60 mice developed prion disease only when inoculated with the H95/wt and H95/S96 CWD allotypes. Serial passage in tg60 mice resulted in adaptation of a novel CWD strain (H95+) with distinct biological properties. Transmission of first-passage tg60CWD-H95+ isolates into tg33 mice, however, elicited two prion disease presentations consistent with a mixture of strains associated with different PrP-res glycotypes. Our data indicate that H95-PRNP heterozygous deer accumulated two CWD strains whose emergence was dictated by the PrPC primary structure of the recipient host. These findings suggest that CWD transmission between cervids expressing distinct PrPC molecules results in the generation of novel CWD strains.
IMPORTANCE CWD prions are contagious among wild and captive cervids in North America and in South Korea. We present data linking the amino acid variant Q95H in white-tailed deer cellular prion protein (PrPC) to the emergence of a novel CWD strain (H95+). We show that, upon infection, deer expressing H95-PrPC molecules accumulated a mixture of CWD strains that selectively propagated depending on the PRNP genotype of the host in which they were passaged. Our study also demonstrates that mice expressing the deer S96-PRNP allele, previously shown to be resistant to various cervid prions, are susceptible to H95+ CWD prions. The potential for the generation of novel strains raises the possibility of an expanded host range for CWD.
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Schneider DA, Madsen-Bouterse SA, Zhuang D, Truscott TC, Dassanayake RP, O'Rourke KI. The placenta shed from goats with classical scrapie is infectious to goat kids and lambs. J Gen Virol 2015; 96:2464-2469. [PMID: 25888622 PMCID: PMC4681073 DOI: 10.1099/vir.0.000151] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The placenta of domestic sheep plays a key role in horizontal transmission of classical scrapie. Domestic goats are frequently raised with sheep and are susceptible to classical scrapie, yet potential routes of transmission from goats to sheep are not fully defined. Sparse accumulation of disease-associated prion protein in cotyledons casts doubt about the role of the goat's placenta. Thus, relevant to mixed-herd management and scrapie-eradication efforts worldwide, we determined if the goat's placenta contains prions orally infectious to goat kids and lambs. A pooled cotyledon homogenate, prepared from the shed placenta of a goat with naturally acquired classical scrapie disease, was used to orally inoculate scrapie-naïve prion genotype-matched goat kids and scrapie-susceptible lambs raised separately in a scrapie-free environment. Transmission was detected in all four goats and in two of four sheep, which importantly identifies the goat's placenta as a risk for horizontal transmission to sheep and other goats.
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Affiliation(s)
- David A Schneider
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA, 99164-6630, USA.,Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164-7040, USA
| | - Sally A Madsen-Bouterse
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164-7040, USA
| | - Dongyue Zhuang
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA, 99164-6630, USA
| | - Thomas C Truscott
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA, 99164-6630, USA
| | - Rohana P Dassanayake
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164-7040, USA
| | - Katherine I O'Rourke
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA, 99164-7040, USA
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Kipanyula M, Chuma I, Brundtland E, Bårdsen K, Msalya G, Kifaro G, Ulvund M. Prion protein (PrP) gene polymorphisms in Small East African and Norwegian white goats. Small Rumin Res 2014. [DOI: 10.1016/j.smallrumres.2014.06.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Adkin A, Donaldson N, Kelly L. A quantitative assessment of the amount of prion diverted to Category 1 materials and wastewater during processing. RISK ANALYSIS : AN OFFICIAL PUBLICATION OF THE SOCIETY FOR RISK ANALYSIS 2013; 33:1197-1211. [PMID: 23278804 DOI: 10.1111/j.1539-6924.2012.01922.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In this article the development and parameterization of a quantitative assessment is described that estimates the amount of TSE infectivity that is present in a whole animal carcass (bovine spongiform encephalopathy [BSE] for cattle and classical/atypical scrapie for sheep and lambs) and the amounts that subsequently fall to the floor during processing at facilities that handle specified risk material (SRM). BSE in cattle was found to contain the most oral doses, with a mean of 9864 BO ID50 s (310, 38840) in a whole carcass compared to a mean of 1851 OO ID50 s (600, 4070) and 614 OO ID50 s (155, 1509) for a sheep infected with classical and atypical scrapie, respectively. Lambs contained the least infectivity with a mean of 251 OO ID50 s (83, 548) for classical scrapie and 1 OO ID50 s (0.2, 2) for atypical scrapie. The highest amounts of infectivity falling to the floor and entering the drains from slaughtering a whole carcass at SRM facilities were found to be from cattle infected with BSE at rendering and large incineration facilities with 7.4 BO ID50 s (0.1, 29), intermediate plants and small incinerators with a mean of 4.5 BO ID50 s (0.1, 18), and collection centers, 3.6 BO ID50 s (0.1, 14). The lowest amounts entering drains are from lambs infected with classical and atypical scrapie at intermediate plants and atypical scrapie at collection centers with a mean of 3 × 10(-7) OO ID50 s (2 × 10(-8) , 1 × 10(-6) ) per carcass. The results of this model provide key inputs for the model in the companion paper published here.
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Affiliation(s)
- Amie Adkin
- Epidemiology, Surveillance and Risk Group, Animal Health and Veterinary Laboratories Agency, Woodham Lane, Weybridge, KT15 3NB, UK.
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Dassanayake RP, Schneider DA, Herrmann-Hoesing LM, Truscott TC, Davis WC, O'Rourke KI. Cell-surface expression of PrPC and the presence of scrapie prions in the blood of goats. J Gen Virol 2012; 93:1127-1131. [PMID: 22278824 DOI: 10.1099/vir.0.039032-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Although host-encoded prion protein (PrP(C)) expression in ovine PBMCs and prion infectivity in scrapie-infected sheep blood have been demonstrated, such studies have not been reported in goats. Therefore, this study characterized cell-surface expression of PrP(C) on PBMC subsets derived from normal goats and sheep, by flow cytometry, and determined prion infectivity in blood from a scrapie-infected goat using a transfusion bioassay in goat kids. Cell-surface PrP(C) expression was detected on all subsets of goat PBMCs. The highest PrP(C) cell-surface expression was found in CD2(+) T lymphocytes in goats. Transmission of infection was detected in all three recipients who received whole blood from a goat with classical scrapie. It was concluded that caprine PBMCs express PrP(C) similarly to sheep but with relative differences among PBMCs subsets, and that blood-borne infectious prions can be detected in scrapie-infected goats. Thus, similar to sheep, goat blood may be a suitable diagnostic target for the detection of scrapie infection.
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Affiliation(s)
- Rohana P Dassanayake
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA
| | - David A Schneider
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164-6630, USA
| | - Lynn M Herrmann-Hoesing
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164-6630, USA
| | - Thomas C Truscott
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164-6630, USA
| | - William C Davis
- Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA
| | - Katherine I O'Rourke
- Animal Disease Research Unit, Agricultural Research Service, US Department of Agriculture, Pullman, WA 99164-6630, USA.,Department of Veterinary Microbiology and Pathology, College of Veterinary Medicine, Washington State University, Pullman, WA 99164-7040, USA
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Cervenakova L, Akimov S, Vasilyeva I, Yakovleva O, McKenzie C, Cervenak J, Piccardo P, Asher DM. Fukuoka-1 strain of transmissible spongiform encephalopathy agent infects murine bone marrow-derived cells with features of mesenchymal stem cells. Transfusion 2011; 51:1755-68. [PMID: 21303371 DOI: 10.1111/j.1537-2995.2010.03041.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND The possible risk of iatrogenic transmissible spongiform encephalopathies (TSEs, prion diseases) from transplantation of marrow-derived mesenchymal stem cells (MSCs) is uncertain. While most cell lines resist infection, a few propagate TSE agents. STUDY DESIGN AND METHODS We generated MSC-like (MSC-L) cell cultures from bone marrow (BM) of mice inoculated with the human-derived Fukuoka-1 (Fu) strain of TSE agent. Cultured cells were characterized for various markers and cellular prion protein (PrP(C) ) by fluorescence-activated cell sorting and for PrP(C) and its pathologic TSE-associated form (PrP(TSE) ) by Western blotting (WB). Cell cultures were tested for their susceptibility to infection with Fu in vitro. The infectivity of one Fu-infected cell culture was assayed in mice. RESULTS BM cells from Fu-infected mice expressed neither PrP(C) nor PrP(TSE) after 3 days in culture as demonstrated by WB. Cells adherent to plastic and maintained under two different culture conditions became spontaneously immortalized and began to express PrP(C) at about the same time. One culture became transformed shortly after exposure to Fu in vitro and remained persistently infected, continuously generating PrP(TSE) through multiple passages; the infectivity of cultured cells was confirmed by intracerebral inoculation of lysates into mice. Both persistently TSE-infected and uninfected cells expressed a number of typical MSC markers. CONCLUSION BM-derived MSC-L cells of mice became persistently infected with the Fu agent under certain conditions in culture-conditions that differ substantially from those currently used to develop investigational human stem cell therapies.
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Affiliation(s)
- Larisa Cervenakova
- Transmissible Diseases Department, American Red Cross Holland Laboratory, Rockville, MD 20855, USA.
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O'Rourke KI, Zhuang D, Truscott TC, Yan H, Schneider DA. Sparse PrP(Sc) accumulation in the placentas of goats with naturally acquired scrapie. BMC Vet Res 2011; 7:7. [PMID: 21284878 PMCID: PMC3041672 DOI: 10.1186/1746-6148-7-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Accepted: 02/01/2011] [Indexed: 12/31/2022] Open
Abstract
Background Domestic goats (Capra hircus) are a natural and experimental host of scrapie and bovine spongiform encephalopathy, the transmissible spongiform encephalopathies (TSE) of sheep and cattle. Goats are also susceptible to experimental infection with the agents of TSEs of deer and elk (chronic wasting disease) and humans (Creutzfeldt Jakob disease). Distribution of PrPSc, the abnormal prion protein, is similar in the tissues of scrapie-infected sheep and goats but no data are available on the potential shedding of the agent through the placenta, the presumed route of transmission of ovine scrapie. We describe the sparse accumulation of PrPSc in the placentas of goats with naturally acquired classical scrapie in comparison to field cases of classical ovine scrapie. Results PrPSc was detected in the shed placentas from a sample of U.S. goats with naturally occurring scrapie, diagnosed by antemortem lymphoid tissue biopsy or identified as high risk progeny of infected dams. PrPSc accumulation patterns in the intact placentome and western blot banding was similar in the caprine and ovine samples. However, levels of PrPSc estimated from ELISA and immunohistochemistry assays were generally lower in goats than in sheep, although wide variation was noted in both species. Conclusions PrPSc accumulates in the shed placentas of goats with naturally acquired scrapie. Although these levels were low in most caprine samples, the caprine placenta may contribute to prion contamination of kidding facilities and transmission to co-housed sheep or goats.
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Affiliation(s)
- Katherine I O'Rourke
- Animal Disease Research Unit, Agricultural Research Service, U.S. Department of Agriculture, Pullman, WA 99164, USA.
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Sisó S, González L, Jeffrey M. Neuroinvasion in prion diseases: the roles of ascending neural infection and blood dissemination. Interdiscip Perspect Infect Dis 2010; 2010:747892. [PMID: 20652006 PMCID: PMC2905956 DOI: 10.1155/2010/747892] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2009] [Accepted: 03/08/2010] [Indexed: 01/27/2023] Open
Abstract
Prion disorders are infectious, neurodegenerative diseases that affect humans and animals. Susceptibility to some prion diseases such as kuru or the new variant of Creutzfeldt-Jakob disease in humans and scrapie in sheep and goats is influenced by polymorphisms of the coding region of the prion protein gene, while other prion disorders such as fatal familial insomnia, familial Creutzfeldt-Jakob disease, or Gerstmann-Straussler-Scheinker disease in humans have an underlying inherited genetic basis. Several prion strains have been demonstrated experimentally in rodents and sheep. The progression and pathogenesis of disease is influenced by both genetic differences in the prion protein and prion strain. Some prion diseases only affect the central nervous system whereas others involve the peripheral organs prior to neuroinvasion. Many experiments undertaken in different species and using different prion strains have postulated common pathways of neuroinvasion. It is suggested that prions access the autonomic nerves innervating peripheral organs and tissues to finally reach the central nervous system. We review here published data supporting this view and additional data suggesting that neuroinvasion may concurrently or independently involve the blood vascular system.
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Affiliation(s)
- Sílvia Sisó
- Veterinary Laboratories Agency (VLA-Lasswade), Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ, UK
| | - Lorenzo González
- Veterinary Laboratories Agency (VLA-Lasswade), Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ, UK
| | - Martin Jeffrey
- Veterinary Laboratories Agency (VLA-Lasswade), Pentlands Science Park, Bush Loan, Penicuik, Midlothian EH26 0PZ, UK
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Hnasko R, Serban AV, Carlson G, Prusiner SB, Stanker LH. Generation of antisera to purified prions in lipid rafts. Prion 2010; 4:94-104. [PMID: 20647769 DOI: 10.4161/pri.4.2.12622] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Prion diseases are fatal neurodegenerative disorders caused by prion proteins (PrP). Infectious prions accumulate in the brain through a template-mediated conformational conversion of endogenous PrP(C) into alternately folded PrP(Sc). Immunoassays toward pre-clinical detection of infectious PrP(Sc) have been confounded by low-level prion accumulation in non-neuronal tissue and the lack of PrP(Sc) selective antibodies. We report a method to purify infectious PrP(Sc) from biological tissues for use as an immunogen and sample enrichment for increased immunoassay sensitivity. Significant prion enrichment is accomplished by sucrose gradient centrifugation of infected tissue and isolation with detergent resistant membranes from lipid rafts (DRMs). At equivalent protein concentration a 50-fold increase in detectable PrP(Sc) was observed in DRM fractions relative to crude brain by direct ELISA. Sequential purification steps result in increased specific infectivity (DRM <20-fold and purified DRM immunogen <40-fold) relative to 1% crude brain homogenate. Purification of PrP(Sc) from DRM was accomplished using phosphotungstic acid protein precipitation after proteinase-K (PK) digestion followed by size exclusion chromatography to separate PK and residual protein fragments from larger prion aggregates. Immunization with purified PrP(Sc) antigen was performed using wild-type (wt) and Prnp(0/0) mice, both on Balb/cJ background. A robust immune response against PrP(Sc) was observed in all inoculated Prnp(0/0) mice resulting in antisera containing high-titer antibodies against prion protein. Antisera from these mice recognized both PrP(C) and PrP(Sc), while binding to other brain-derived protein was not observed. In contrast, the PrP(Sc) inoculum was non-immunogenic in wt mice and antisera showed no reactivity with PrP or any other protein.
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Affiliation(s)
- Robert Hnasko
- USDA Agricultural Research Service, Foodborne Contaminants Research Unit, Albany, CA, USA
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Konold T, Bone GE, Phelan LJ, Simmons MM, González L, Sisó S, Goldmann W, Cawthraw S, Hawkins SAC. Monitoring of clinical signs in goats with transmissible spongiform encephalopathies. BMC Vet Res 2010; 6:13. [PMID: 20202205 PMCID: PMC2875668 DOI: 10.1186/1746-6148-6-13] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2009] [Accepted: 03/04/2010] [Indexed: 12/01/2022] Open
Abstract
Background As there is limited information about the clinical signs of BSE and scrapie in goats, studies were conducted to describe the clinical progression of scrapie and BSE in goats and to evaluate a short clinical protocol for its use in detecting scrapie-affected goats in two herds with previously confirmed scrapie cases. Clinical assessments were carried out in five goats intracerebrally infected with the BSE agent as well as five reported scrapie suspects and 346 goats subject to cull from the two herds, 24 of which were retained for further monitoring. The brain and selected lymphoid tissue were examined by postmortem tests for disease confirmation. Results The sensitivity and specificity of the short clinical protocol in detecting a scrapie case in the scrapie-affected herds was 3.9% and 99.6%, respectively, based on the presence of tremor, positive scratch test, extensive hair loss, ataxia and absent menace response. All BSE- and scrapie-affected goats displayed abnormalities in sensation (over-reactivity to external stimuli, startle responses, pruritus, absent menace response) and movement (ataxia, tremor, postural deficits) at an advanced clinical stage but the first detectable sign associated with scrapie or BSE could vary between animals. Signs of pruritus were not always present despite similar prion protein genotypes. Clinical signs of scrapie were also displayed by two scrapie cases that presented with detectable disease-associated prion protein only in lymphoid tissues. Conclusions BSE and scrapie may present as pruritic and non-pruritic forms in goats. Signs assessed for the clinical diagnosis of scrapie or BSE in goats should include postural and gait abnormalities, pruritus and visual impairment. However, many scrapie cases will be missed if detection is solely based on the display of clinical signs. PrPd accumulation in the brain appeared to be related to the severity of clinical disease but not to the display of individual neurological signs.
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Affiliation(s)
- Timm Konold
- Neuropathology, Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, KT15 3NB, UK.
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Vaccari G, Panagiotidis CH, Acin C, Peletto S, Barillet F, Acutis P, Bossers A, Langeveld J, van Keulen L, Sklaviadis T, Badiola JJ, Andreéoletti O, Groschup MH, Agrimi U, Foster J, Goldmann W. State-of-the-art review of goat TSE in the European Union, with special emphasis on PRNP genetics and epidemiology. Vet Res 2009; 40:48. [PMID: 19505422 PMCID: PMC2704333 DOI: 10.1051/vetres/2009031] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Accepted: 05/22/2009] [Indexed: 11/25/2022] Open
Abstract
Scrapie is a fatal, neurodegenerative disease of sheep and goats. It is also the earliest known member in the family of diseases classified as transmissible spongiform encephalopathies (TSE) or prion diseases, which includes Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE), and chronic wasting disease in cervids. The recent revelation of naturally occurring BSE in a goat has brought the issue of TSE in goats to the attention of the public. In contrast to scrapie, BSE presents a proven risk to humans. The risk of goat BSE, however, is difficult to evaluate, as our knowledge of TSE in goats is limited. Natural caprine scrapie has been discovered throughout Europe, with reported cases generally being greatest in countries with the highest goat populations. As with sheep scrapie, susceptibility and incubation period duration of goat scrapie are most likely controlled by the prion protein (PrP) gene (PRNP). Like the PRNP of sheep, the caprine PRNP shows significantly greater variability than that of cattle and humans. Although PRNP variability in goats differs from that observed in sheep, the two species share several identical alleles. Moreover, while the ARR allele associated with enhancing resistance in sheep is not present in the goat PRNP, there is evidence for the existence of other PrP variants related to resistance. This review presents the current knowledge of the epidemiology of caprine scrapie within the major European goat populations, and compiles the current data on genetic variability of PRNP.
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Affiliation(s)
- Gabriele Vaccari
- Department of Food Safety and Veterinary Public Health, Unit of Transmissible Spongiform Encephalopathies and Emerging Infectious Diseases of Animals, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161, Rome, Italy
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16
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Franscini N, Gedaily AE, Matthey U, Franitza S, Sy MS, Bürkle A, Groschup M, Braun U, Zahn R. Prion protein in milk. PLoS One 2006; 1:e71. [PMID: 17183703 PMCID: PMC1762385 DOI: 10.1371/journal.pone.0000071] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2006] [Accepted: 11/06/2006] [Indexed: 11/20/2022] Open
Abstract
Background Prions are known to cause transmissible spongiform encephalopathies (TSE) after accumulation in the central nervous system. There is increasing evidence that prions are also present in body fluids and that prion infection by blood transmission is possible. The low concentration of the proteinaceous agent in body fluids and its long incubation time complicate epidemiologic analysis and estimation of spreading and thus the risk of human infection. This situation is particularly unsatisfactory for food and pharmaceutical industries, given the lack of sensitive tools for monitoring the infectious agent. Methodology/Principal Findings We have developed an adsorption matrix, Alicon PrioTrap®, which binds with high affinity and specificity to prion proteins. Thus we were able to identify prion protein (PrPC)–the precursor of prions (PrPSc)–in milk from humans, cows, sheep, and goats. The absolute amount of PrPC differs between the species (from µg/l range in sheep to ng/l range in human milk). PrPC is also found in homogenised and pasteurised off-the-shelf milk, and even ultrahigh temperature treatment only partially diminishes endogenous PrPC concentration. Conclusions/Significance In view of a recent study showing evidence of prion replication occurring in the mammary gland of scrapie infected sheep suffering from mastitis, the appearance of PrPC in milk implies the possibility that milk of TSE-infected animals serves as source for PrPSc.
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Affiliation(s)
| | | | | | | | - Man-Sun Sy
- Institute of Pathology, Biomedical Research Building, Case Western University School of MedicineCleveland, Ohio, United States of America
| | - Alexander Bürkle
- Lehrstuhl Molekulare Toxikologie, University of KonstanzKonstanz, Germany
| | - Martin Groschup
- Friedrich-Loeffler-Institut, Bundesforschungsinstitut für TiergesundheitGreifswald, Gemany
| | - Ueli Braun
- Departement für Nutztiere, University of ZurichZurich, Switzerland
| | - Ralph Zahn
- Alicon AGSchlieren, Switzerland
- * To whom correspondence should be addressed. E-mail:
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17
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Sofianidis G, Psychas V, Billinis C, Spyrou V, Argyroudis S, Papaioannou N, Vlemmas I. Histopathological and immunohistochemical features of natural goat scrapie. J Comp Pathol 2006; 135:116-129. [PMID: 16997004 DOI: 10.1016/j.jcpa.2006.06.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Accepted: 06/11/2006] [Indexed: 10/24/2022]
Abstract
Histopathological and immunohistochemical examinations were performed on the brain and spinal cord of 37 goats from two Greek herds in which scrapie had been reported. Of the 37 animals, 18 were from a herd consisting only of goats and 19 were from a herd of goats mixed with sheep. The goats studied were grouped on the basis of the presence or absence of clinical signs. Distinctive lesions and PrP(sc) (PrP, prion protein) deposition were found in the central nervous system (CNS) of eight clinically affected animals and six symptomless animals. The lesion profile and PrP(sc) distribution varied both between and within groups, variation being particularly pronounced in the symptomless goats. The results concerning the latter group suggested a poor correlation between the intensity of lesions, the amount of PrP(sc) in the CNS, and the manifestation of clinical signs. Immunohistochemical examination revealed 10 different PrP(sc) types, four of which are reported for the first time in goats. All scrapie-affected animals carried the VV(21)II(142)HH(143)RR(154) genotype, with the exception of two goats that carried the HR(143) dimorphism and had detectable PrP(sc) deposits. The results suggest that the histopathological and immunohistochemical profile of the natural disease in goats is influenced by the PrP genotype and age of the animals but may not be directly associated with the presence or otherwise of clinical signs.
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Affiliation(s)
| | | | - C Billinis
- Laboratory of Microbiology and Parasitology, Faculty of Veterinary Medicine, University of Thessaly, Trikalon 224, 43100 Karditsa
| | - V Spyrou
- Department of Animal Production, Technological Educational Institution, Larissa, Greece
| | - S Argyroudis
- Clinic of Productive Animal Medicine, Faculty of Veterinary Medicine, Aristotle University, 54124 Thessaloniki
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18
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19
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Opinion of the Scientific Panel on biological hazards (BIOHAZ) on the usefulness of somatic cell counts for safety of milk and milk derived products from goats. EFSA J 2005. [DOI: 10.2903/j.efsa.2005.305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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20
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Abstract
Proprietary concentrates and milk replacers were linked to risk for scrapie. Scrapie is a small ruminant, transmissible spongiform encephalopathy (TSE). Although in the past scrapie has not been considered a zoonosis, the emergence of bovine spongiform encephalopathy, transmissible to humans and experimentally to sheep, indicates that risk exists for small ruminant TSEs in humans. To identify the risk factors for introducing scrapie into sheep flocks, a case-control study was conducted in France from 1999 to 2000. Ninety-four case and 350 control flocks were matched by location and main breed. Three main hypotheses were tested: direct contact between flocks, indirect environmental contact, and foodborne risk. Statistical analysis was performed by using adjusted generalized linear models with the complementary log-log link function, considering flock size as an offset. A notable effect of using proprietary concentrates and milk replacers was observed. The risk was heterogeneous among feed factories. Contacts between flocks were not shown to be a risk factor.
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Affiliation(s)
| | | | - Pascal Roy
- Centre Hospitalo-Universitaire Lyon-Sud, Lyon, France
| | | | - Nathalie Jarrige
- Agence Française de Sécurité Sanitaire des Aliments, Lyon, France
| | - Didier Calavas
- Agence Française de Sécurité Sanitaire des Aliments, Lyon, France
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21
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Wilesmith JW. Bovine spongiform encephalopathy and related diseases: an epidemiological overview. N Z Vet J 2005; 42:1-8. [PMID: 16031734 DOI: 10.1080/00480169.1994.35774] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Following the recognition of the novel disease bovine spongiform encephalopathy in Great Britain in 1986, epidemiological and other research studies were initiated. The initial results of these studies revealed that bovine spongiform encephalopathy was caused by a scrapie-like agent and the vehicle of infection was meat-and-bone meal incorporated into cattle feedstuffs as a protein source. The British cattle population became effectively exposed in 1981-82 and this was associated with a dramatic reduction in the use of hydrocarbon solvents for the extraction of fat in the production of meat-and-bone meal. The feeding of ruminant-derived protein to ruminants was statutorily banned in July 1988 to prevent further exposure from the food-borne source. This paper reviews the epidemiological aspects of bovine spongiform encephalopathy and the occurrence of transmissible spongiform encephalopathies in other species.
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Affiliation(s)
- J W Wilesmith
- Epidemiology Department, Central Veterinary Laboratory, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
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22
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Opinion of the Scientific Panel on biological hazards (BIOHAZ) on: “A quantitative assessment of risk posed to humans by tissues of small ruminants in case BSE is present in these animal populations”. EFSA J 2005. [DOI: 10.2903/j.efsa.2005.227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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23
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Safar JG, Geschwind MD, Deering C, Didorenko S, Sattavat M, Sanchez H, Serban A, Vey M, Baron H, Giles K, Miller BL, Dearmond SJ, Prusiner SB. Diagnosis of human prion disease. Proc Natl Acad Sci U S A 2005; 102:3501-6. [PMID: 15741275 PMCID: PMC552933 DOI: 10.1073/pnas.0409651102] [Citation(s) in RCA: 232] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
With the discovery of the prion protein (PrP), immunodiagnostic procedures were applied to diagnose Creutzfeldt-Jakob disease (CJD). Before development of the conformation-dependent immunoassay (CDI), all immunoassays for the disease-causing PrP isoform (PrPSc) used limited proteolysis to digest the precursor cellular PrP (PrPC). Because the CDI is the only immunoassay that measures both the protease-resistant and protease-sensitive forms of PrPSc, we used the CDI to diagnose human prion disease. The CDI gave a positive signal for PrPSc in all 10-24 brain regions (100%) examined from 28 CJD patients. A subset of 18 brain regions from 8 patients with sporadic CJD (sCJD) was examined by histology, immunohistochemistry (IHC), and the CDI. Three of the 18 regions (17%) were consistently positive by histology and 4 of 18 (22%) by IHC for the 8 sCJD patients. In contrast, the CDI was positive in all 18 regions (100%) for all 8 sCJD patients. In both gray and white matter, approximately 90% of the total PrPSc was protease-sensitive and, thus, would have been degraded by procedures using proteases to eliminate PrPC. Our findings argue that the CDI should be used to establish or rule out the diagnosis of prion disease when a small number of samples is available as is the case with brain biopsy. Moreover, IHC should not be used as the standard against which all other immunodiagnostic techniques are compared because an immunoassay, such as the CDI, is substantially more sensitive.
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Affiliation(s)
- Jiri G Safar
- Institute for Neurodegenerative Diseases, Memory and Aging Center, University of California, San Francisco, CA 94143, USA
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24
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Abstract
Although human prion diseases are rare, they are invariably fatal, and treatments remain elusive. Hundreds of iatrogenic prion transmissions have occurred in the past two decades, and the bovine spongiform encephalopathy epidemic has raised concerns about prion transmission from cattle to humans. Research into therapeutics for prion disease is being pursued in several centres and prominently includes immunological strategies. Currently, the options that are being explored aim either to mobilize the innate and adaptive immune systems towards prion destruction or to suppress or dedifferentiate the lymphoreticular compartments that replicate prions. This article reviews the pathophysiology of prion diseases in mouse models and discusses their relevance to immunotherapeutic and immunoprophylactic antiprion strategies.
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Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, University Hospital Zürich, Switzerland.
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25
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Cunningham AA, Kirkwood JK, Dawson M, Spencer YI, Green RB, Wells GAH. Bovine spongiform encephalopathy infectivity in greater kudu (Tragelaphus strepsiceros). Emerg Infect Dis 2004; 10:1044-9. [PMID: 15207051 PMCID: PMC3323176 DOI: 10.3201/eid1006.030615] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Of all the species exposed naturally to the bovine spongiform encephalopathy (BSE) agent, the greater kudu (Tragelaphus strepsiceros), a nondomesticated bovine from Africa, appears to be the most susceptible to the disease. We present the results of mouse bioassay studies to show that, contrary to findings in cattle with BSE in which the tissue distribution of infectivity is the most limited recorded for any of the transmissible spongiform encephalopathies (TSE), infectivity in greater kudu with BSE is distributed in as wide a range of tissues as occurs in any TSE. BSE agent was also detected in skin, conjunctiva, and salivary gland, tissues in which infectivity has not previously been reported in any naturally occurring TSE. The distribution of infectivity in greater kudu with BSE suggests possible routes for transmission of the disease and highlights the need for further research into the distribution of TSE infectious agents in other host species.
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26
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Mulcahy ER, Bartz JC, Kincaid AE, Bessen RA. Prion infection of skeletal muscle cells and papillae in the tongue. J Virol 2004; 78:6792-8. [PMID: 15194754 PMCID: PMC421640 DOI: 10.1128/jvi.78.13.6792-6798.2004] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The presence of the prion agent in skeletal muscle is thought to be due to the infection of nerve fibers located within the muscle. We report here that the pathological isoform of the prion protein, PrP(Sc), accumulates within skeletal muscle cells, in addition to axons, in the tongue of hamsters following intralingual and intracerebral inoculation of the HY strain of the transmissible mink encephalopathy agent. Localization of PrP(Sc) to the neuromuscular junction suggests that this synapse is a site for prion agent spread between motor axon terminals and muscle cells. Following intracerebral inoculation, the majority of PrP(Sc) in the tongue was found in the lamina propria, where it was associated with sensory nerve fibers in the core of the lingual papillae. PrP(Sc) staining was also identified in the stratified squamous epithelium of the lingual mucosa. These findings indicate that prion infection of skeletal muscle cells and the epithelial layer in the tongue can be established following the spread of the prion agent from nerve terminals and/or axons that innervate the tongue. Our data suggest that ingestion of meat products containing prion-infected tongue could result in human exposure to the prion agent, while sloughing of prion-infected epithelial cells at the mucosal surface of the tongue could be a mechanism for prion agent shedding and subsequent prion transmission in animals.
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Affiliation(s)
- Ellyn R Mulcahy
- Department of Medical Microbiology and Immunology, Creighton University, Omaha, NE, USA
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27
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Abstract
Scrapie and CWD share many features. There are marked similarities in the clinical presentations, the lesions, and the pathogenesis of these diseases, and some similarities in the epidemiology. Extrapolation from the scrapie model of TSE disease to CWD--which occurs in three different species, and should not be considered to be uniform in their response--may be erroneous, however. Such differences may influence diagnostics (e.g., the amount and distribution of PrPC in these different species), pathogenesis (e.g., the influence of genetics on susceptibility and resistance), and epidemiology (e.g., the mode and dynamics of transmission and influences of domestication). IHC is used widely for diagnostics and in the study of the pathogenesis of scrapie and CWD. This technique holds promise for antemortem diagnosis of infection in the peripheral lymphoid tissues such as lymphoid follicles of the nictitating membrane and the tonsil.
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Affiliation(s)
- Elizabeth S Williams
- Department of Veterinary Sciences, University of Wyoming, 1174 Snowy Range Road, Laramie, WY 82070, USA.
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28
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Valdez RA, Rock MJ, Anderson AK, O'Rourke KI. Immunohistochemical detection and distribution of prion protein in a goat with natural scrapie. J Vet Diagn Invest 2003; 15:157-62. [PMID: 12661726 DOI: 10.1177/104063870301500210] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Formalin-fixed, paraffin-embedded tissue sections from a 3-year-old female Angora goat suffering from clinical scrapie were immunostained after hydrated autoclaving using a monoclonal antibody (mAb, F99/97.6.1; IgG1) specific for a conserved epitope on the prion protein. Widespread and prominent deposition of the scrapie isoform of the prion protein (PrPSc) was observed in the brain, brainstem, spinal cord, retina, postganglionic neurons associated with parasympathetic ganglia of myenteric and submucosal plexuses, Peyer's patches, peripheral lymph nodes, and pharyngeal and palatine tonsils. The goat was homozygous for PrP alleles encoding 5 octapeptide repeat sequences in the N-terminal region of the prion protein and isoleucine at codon 142, a genotype associated with high susceptibility and short incubation times in goats. The results of this study indicate that mAb F99/97.6.1 is useful for detection of PrPSc deposition, and this is a specific and reliable immunohistochemical adjunct to histopathology for diagnosis of natural caprine scrapie, although precise determination of the diagnostic sensitivity and specificity of the assay as a diagnostic test for scrapie in goats will require examination of a sufficiently large sample size. As with ovine scrapie, prion protein is widely distributed in the central and peripheral nervous systems, gastrointestinal tract, and lymphoid tissues in natural caprine scrapie.
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Affiliation(s)
- Reginald A Valdez
- Animal Disease Research Unit, United States Department of Agriculture, Agricultural Research Service, Pullman, WA 99164-6630, USA
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29
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Balen A. Is there a risk of prion disease after the administration of urinary-derived gonadotrophins? Hum Reprod 2002; 17:1676-80. [PMID: 12093821 DOI: 10.1093/humrep/17.7.1676-a] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Concern has been raised recently about the possibility of prion proteins appearing in the urine of animals and, possibly, humans affected by prion disease [scrapie, bovine spongiform encephalopathy (BSE) and Creutzfeldt Jakob disease (CJD)]. A debate has started in which the suggestion has been made that the purification of human urine for the provision of gonadotrophins should be discontinued. The alternative would be to use recombinantly-derived gonadotrophin preparations. The recombinant products, however, rely upon bovine serum during the cell culture process and could potentially also be exposed to abnormal prion proteins. It is reassuring that the different types of gonadotrophin preparations that are currently available are produced with either urine or bovine serum that is sourced from countries that at the present time appear to be free of BSE and new variant CJD. We can therefore be reassured that the gonadotrophins that we use therapeutically appear to be equally safe.
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Affiliation(s)
- Adam Balen
- Department of Reproductive Medicine, The General Infirmary, Leeds LS2 9NS, UK.
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30
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Bosque PJ, Ryou C, Telling G, Peretz D, Legname G, DeArmond SJ, Prusiner SB. Prions in skeletal muscle. Proc Natl Acad Sci U S A 2002; 99:3812-7. [PMID: 11904434 PMCID: PMC122606 DOI: 10.1073/pnas.052707499] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Considerable evidence argues that consumption of beef products from cattle infected with bovine spongiform encephalopathy (BSE) prions causes new variant Creutzfeldt-Jakob disease. In an effort to prevent new variant Creutzfeldt-Jakob disease, certain "specified offals," including neural and lymphatic tissues, thought to contain high titers of prions have been excluded from foods destined for human consumption [Phillips, N. A., Bridgeman, J. & Ferguson-Smith, M. (2000) in The BSE Inquiry (Stationery Office, London), Vol. 6, pp. 413-451]. Here we report that mouse skeletal muscle can propagate prions and accumulate substantial titers of these pathogens. We found both high prion titers and the disease-causing isoform of the prion protein (PrP(Sc)) in the skeletal muscle of wild-type mice inoculated with either the Me7 or Rocky Mountain Laboratory strain of murine prions. Particular muscles accumulated distinct levels of PrP(Sc), with the highest levels observed in muscle from the hind limb. To determine whether prions are produced or merely accumulate intramuscularly, we established transgenic mice expressing either mouse or Syrian hamster PrP exclusively in muscle. Inoculating these mice intramuscularly with prions resulted in the formation of high titers of nascent prions in muscle. In contrast, inoculating mice in which PrP expression was targeted to hepatocytes resulted in low prion titers. Our data demonstrate that factors in addition to the amount of PrP expressed determine the tropism of prions for certain tissues. That some muscles are intrinsically capable of accumulating substantial titers of prions is of particular concern. Because significant dietary exposure to prions might occur through the consumption of meat, even if it is largely free of neural and lymphatic tissue, a comprehensive effort to map the distribution of prions in the muscle of infected livestock is needed. Furthermore, muscle may provide a readily biopsied tissue from which to diagnose prion disease in asymptomatic animals and even humans.
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Affiliation(s)
- Patrick J Bosque
- Institute for Neurodegenerative Diseases, Department of Neurology, University of California, San Francisco, CA 94143, USA
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31
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Cervenakova L, Brown P, Hammond DJ, Lee CA, Saenko EL. Factor VIII and transmissible spongiform encephalopathy: the case for safety. Haemophilia 2002; 8:63-75. [PMID: 11952840 DOI: 10.1046/j.1365-2516.2002.00617.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Haemophilia A is the most common inherited bleeding disorder, caused by a deficiency in coagulation factor VIII (FVIII). Current treatment of haemophilia A is based on repeated infusions of plasma-derived FVIII concentrate or of recombinant FVIII, which may be exposed to plasma-derived material of human or animal origin used in its tissue culture production process. We review epidemiological and experimental studies relevant to blood infectivity in the transmissible spongiform encephalopathies (TSEs, or 'prion' diseases), and evaluate the hypothetical risk of TSE transmission through treatment with plasma-derived or recombinant FVIII.
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Affiliation(s)
- L Cervenakova
- J. Holland Laboratory, American Red Cross, Rockville, MD 20855, USA.
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32
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Billinis C, Panagiotidis CH, Psychas V, Argyroudis S, Nicolaou A, Leontides S, Papadopoulos O, Sklaviadis T. Prion protein gene polymorphisms in natural goat scrapie. J Gen Virol 2002; 83:713-721. [PMID: 11842266 DOI: 10.1099/0022-1317-83-3-713] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A total of 51 goats, including seven clinical cases, from the first herd in Greece reported to have scrapie was examined to discern an association between scrapie susceptibility and polymorphisms of the gene encoding the prion protein (PrP). Each animal was evaluated for clinical signs of the disease, histopathological lesions associated with scrapie, the presence of detectable protease-resistant PrP in the brain and PrP genotype. Eleven different PrP genotypes encoding at least five unique predicted mature PrP amino acid sequences were found. These genotypes included the amino acid polymorphisms at codons 143 (H-->R) and 240 (S-->P) and 'silent' nucleotide alterations at codons 42 (a-->g) and 138 (c-->t). Additionally, novel caprine amino acid polymorphisms were detected at codons 21 (V-->A), 23 (L-->P), 49 (G-->S), 154 (R-->H), 168 (P-->Q) and 220 (Q-->H) and new silent mutations were found at codons 107 (g-->a) and 207 (g-->a). The following variants were found in scrapie-affected goats: VV(21), LL(23), GG(49,) SS(49), HH(143), HR(143), RR(154), PP(168), PP(240), SP(240) and SS(240). All scrapie-affected animals carried the HH(143)RR(154) genotype, with the exception of two goats (HR(143)), both of which had detectable protease-resistant PrP but showed no clinical signs or histopathological lesions characteristic of scrapie.
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Affiliation(s)
- Charalambos Billinis
- Laboratory of Microbiology and Infectious Diseases1, Laboratory of Pathology3 and Clinic of Productive Animal Medicine4, Faculty of Veterinary Medicine, Aristotle University, 54006 Thessaloniki, Greece
| | - Cynthia H Panagiotidis
- Laboratory of Pharmacology, Department of Pharmaceutical Sciences, Aristotle University, 54006 Thessaloniki, Greece2
| | - Vassilios Psychas
- Laboratory of Microbiology and Infectious Diseases1, Laboratory of Pathology3 and Clinic of Productive Animal Medicine4, Faculty of Veterinary Medicine, Aristotle University, 54006 Thessaloniki, Greece
| | - Stamatis Argyroudis
- Laboratory of Microbiology and Infectious Diseases1, Laboratory of Pathology3 and Clinic of Productive Animal Medicine4, Faculty of Veterinary Medicine, Aristotle University, 54006 Thessaloniki, Greece
| | - Anna Nicolaou
- University of Macedonia, Department of Business Administration, 156 Egnatia Street, 54006 Thessaloniki, Greece5
| | - Sotirios Leontides
- Laboratory of Microbiology and Infectious Diseases1, Laboratory of Pathology3 and Clinic of Productive Animal Medicine4, Faculty of Veterinary Medicine, Aristotle University, 54006 Thessaloniki, Greece
| | - Orestis Papadopoulos
- Laboratory of Microbiology and Infectious Diseases1, Laboratory of Pathology3 and Clinic of Productive Animal Medicine4, Faculty of Veterinary Medicine, Aristotle University, 54006 Thessaloniki, Greece
| | - Theodoros Sklaviadis
- Laboratory of Pharmacology, Department of Pharmaceutical Sciences, Aristotle University, 54006 Thessaloniki, Greece2
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33
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Spraker TR, Zink RR, Cummings BA, Wild MA, Miller MW, O'Rourke KI. Comparison of histological lesions and immunohistochemical staining of proteinase-resistant prion protein in a naturally occurring spongiform encephalopathy of free-ranging mule deer (Odocoileus hemionus) with those of chronic wasting disease of captive mule deer. Vet Pathol 2002; 39:110-9. [PMID: 12102202 DOI: 10.1354/vp.39-1-110] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this investigation, the nature and distribution of histologic lesions and immunohistochemical staining (IHC) of a proteinase-resistant prion protein were compared in free-ranging mule deer (Odocoileus hemionus) dying of a naturally occurring spongiform encephalopathy (SE) and captive mule deer dying of chronic wasting disease (CWD). Sixteen free-ranging deer with SE, 12 free-ranging deer without SE, and 10 captive deer with CWD were examined at necropsy. Tissue sections were stained with hematoxylin and eosin, and duplicate sections were stained with a monoclonal antibody (F89/160.1.5). Histological lesions in the free-ranging deer with SE and captive deer with CWD were found throughout the brain and spinal cord but were especially prominent in the myelencephalon, diencephalon, and rhinencephalon. The lesions were characterized by spongiform degeneration of gray matter neuropil, intracytoplasmic vacuolation and degeneration of neurons, and astrocytosis. IHC was found throughout the brain and retina of deer with SE and CWD. Positive IHC was found in lymphoid tissue of deer with SE and CWD. Histologic lesions and IHC were not found in multiple sections of integument, digestive, respiratory, cardiovascular, endocrine, musculoskeletal, and urogenital systems of deer with SE or CWD. Comparison of histologic lesions and IHC in tissues of free-ranging deer with those of captive deer provides strong evidence that these two diseases are indistinguishable morphologically.
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Affiliation(s)
- T R Spraker
- Department of Pathology, College of Veterinary Medicine, Colorado State University, Fort Collins 80523, USA
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34
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Abstract
Studies in experimental animals and case-reports of transmission of Creutzfeldt-Jakob Disease (CJD) by blood transfusion or by albumin products have raised the possibility that CJD may be transmitted by transfusion. The risk of transmission of CJD by transfusion remains theoretical, since no confirmed case of CJD has ever been causally attributed to the receipt of a blood transfusion, no confirmed case of CJD has developed in recipients of clotting factor concentrates, and no cluster of CJD cases has been reported following the administration of a pooled plasma derivative to which a donor who subsequently developed CJD had contributed. However, based on a review of the hitherto available data, it is impossible to conclude at this time that CJD is not transmitted by blood or plasma transfusion or by the administration of pooled plasma derivatives. This review discusses the findings of the animal experiments and the human studies that investigated the potential for transmission of CJD among humans by transfusion, and explains the statistical difficulties associated with proving the negative hypothesis that CJD is not transmitted by transfusion.
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Affiliation(s)
- E C Vamvakas
- Department of Pathology, New York Department of Veterans Affairs Medical Center and New York University School of Medicine, New York, New York 10016, USA.
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35
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Lngrosso L, Pisani F, Pocchiari M. Transmission of the 263K scrapie strain by the dental route. J Gen Virol 1999; 80 ( Pt 11):3043-3047. [PMID: 10580068 DOI: 10.1099/0022-1317-80-11-3043] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Apart from a few cases of iatrogenic and familial human transmissible spongiform encephalopathies (TSEs) or prion diseases, the cause of Creutzfeldt-Jakob disease (CJD) remains unknown. In this paper we investigated the possibility that dental procedures may represent a potential route of infection. This was assessed by using the experimental model of scrapie in hamster. In the first part of this study we found that after intraperitoneal inoculation, oral tissues commonly involved in dental procedures (gingival and pulp tissues) bore a substantial level of infectivity. We also found high scrapie infectivity in the trigeminal ganglia, suggesting that the scrapie agent had reached the oral tissues through the sensitive terminal endings of the trigeminal nerves. In the second part of the study we inoculated a group of hamsters in the tooth pulp and showed that all of them developed scrapie disease. In these animals, we detected both infectivity and the pathological prion protein (PrPsc) in the trigeminal ganglion homolateral to the site of injection but not in the controlateral one. This finding suggests that the scrapie agent, and likely other TSE agents as well, spreads from the buccal tissues to the central nervous system through trigeminal nerves. Although these findings may not apply to humans affected by TSEs, they do raise concerns about the possible risk of transmitting these disorders through dental procedures. Particular consideration should be taken in regard to new variant CJD patients because they may harbour more infectivity in peripheral tissues than sporadic CJD patients.
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Affiliation(s)
- Loredana Lngrosso
- Laboratory of Virology, lstituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy1
| | - Flavio Pisani
- Laboratory of Virology, lstituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy1
| | - Maurizio Pocchiari
- Laboratory of Virology, lstituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy1
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36
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Wells GA, Hawkins SA, Green RB, Spencer YI, Dexter I, Dawson M. Limited detection of sternal bone marrow infectivity in the clinical phase of experimental bovine spongiform encephalopathy (BSE). Vet Rec 1999; 144:292-4. [PMID: 10204225 DOI: 10.1136/vr.144.11.292] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- G A Wells
- Veterinary Laboratories Agency, Addlestone, Surrey
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37
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Schreuder BE, van Keulen LJ, Vromans ME, Langeveld JP, Smits MA. Tonsillar biopsy and PrPSc detection in the preclinical diagnosis of scrapie. Vet Rec 1998; 142:564-8. [PMID: 9634704 DOI: 10.1136/vr.142.21.564] [Citation(s) in RCA: 137] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Preliminary findings have indicated that in naturally infected sheep, fully susceptible to scrapie (VRQ-homozygous), PrPSc can be detected in the tonsils approximately one year before the expected onset of clinical disease, whereas no immunostaining can be detected in animals with a semi-resistant genotype. This paper describes the technique for taking tonsillar biopsies from sheep and gives the results of the completed experiment. In another experiment PrPSc was detected even earlier in comparable VRQ-homozygous sheep born and raised in different surroundings. At three-and-a-half months of age no PrPSc could be detected in three homozygous susceptible sheep (VRQ/VRQ), but PrPSc was detected at four months in one similar sheep. At eight months of age all seven sampled VRQ/VRQ sheep showed positive immunostaining in the biopsies, but none of the biopsies from three VRQ/ARQ heterozygotes showed any immunostaining; they were positive when sampled at 14 to 15 months of age. Biopsies from VRQ/ARR sheep were negative throughout this period. On the basis of the established or expected incubation period, PrPSc could thus be detected in the tonsils of live susceptible animals at between one-third and a half of the incubation period, more than one-and-a-half years before clinical signs normally appear in both these genotypes.
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Affiliation(s)
- B E Schreuder
- DLO-Institute for Animal Science and Health (ID-DLO), Lelystad, The Netherlands
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38
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Jeffrey M, Goodsir CM, Holliman A, Higgins RJ, Bruce ME, McBride PA, Fraser JR. Determination of the frequency and distribution of vascular and parenchymal amyloid with polyclonal and N-terminal-specific PrP antibodies in scrapie-affected sheep and mice. Vet Rec 1998; 142:534-7. [PMID: 9637378 DOI: 10.1136/vr.142.20.534] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Brains from 17 histopathologically confirmed cases of scrapie, five of which had congophilic vascular amyloid, were stained immunohistochemically for prion protein (PrP) using a polyclonal antibody. Two clinically suspect but pathologically unconfirmed cases of natural sheep scrapie and the brains of four mice infected with the 111A murine scrapie strain were also examined. Selected sections containing amyloid were stained with each of two peptide antibodies which recognise the N-terminal amino acid residues which are lost following protease digestion of the disease-specific isoform of PrP. The mice infected with the 111A murine scrapie strain had large numbers of hypermature plaques. All the amyloid plaques from both natural sheep scrapie brains and experimental murine brains were heavily immunostained by the polyclonal and both peptide antibodies. In addition, disease-specific accumulations of PrP were detected in endothelial cells or in the intima of blood vessels of the cerebral cortex of sheep scrapie brains. The affected blood vessels were located in areas which otherwise lacked typical scrapie pathology. Vascular accumulations of PrP were also found in leptomeningeal and choroid plexus blood vessels. Vascular amyloid was found mainly in the neocortex. Vascular amyloid and disease-specific parenchymal accumulations of PrP were found in two sheep which showed clinical signs of scrapie but lacked its typical vacuolar pathology. These results show that the mature amyloid of scrapie is composed of, or contains a substantial proportion of, whole length PrP protein. Thus truncation of PrP is not essential for the aggregation of PrP into amyloid. The vascular amyloid of natural sheep scrapie originates from the accumulation and release of PrP from endothelial cells presumably following systemic scrapie infection. The topography of vascular amyloid distribution in Great Britain differs from that reported in the Netherlands. As amyloid deposition in mice is largely controlled by the strain of the infecting agent it is possible that the strain of the agent may influence vascular amyloid deposition.
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Affiliation(s)
- M Jeffrey
- Lasswade Veterinary Laboratory, Bush Estate, Penicuik, Midlothian
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39
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Godon KA, Honstead J. Transmissible spongiform encephalopathies in food animals. Human food safety and animal feed safety concerns for veterinarians. Vet Clin North Am Food Anim Pract 1998; 14:49-70. [PMID: 9532667 DOI: 10.1016/s0749-0720(15)30279-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
This article presents a brief overview of transmissible spongiform encephalopathies (TSEs) using examples of diseases that provide evidence supporting oral transmission of the agent. Agent theories are described briefly in general terms. Scrapie, bovine spongiform encephalopathy (BSE), chronic wasting disease, and transmissible mink encephalopathy are discussed to improve disease recognition by the food animal practitioner. Control programs for scrapie and BSE are described and the role of the veterinarian in animal feed and human food safety is related to TSEs.
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Affiliation(s)
- K A Godon
- Center for Veterinary Medicine, United States Food and Drug Administration, Rockville, Maryland, USA
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40
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Taylor DM. Bovine spongiform encephalopathy--the beginning of the end? THE BRITISH VETERINARY JOURNAL 1996; 152:501-18. [PMID: 8885462 DOI: 10.1016/s0007-1935(96)80004-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The incidence of bovine spongiform encephalopathy (BSE) in the United Kingdom is now declining at a significant rate, indicating that the 1988 ban on feeding ruminant-derived meat and bone meal to cattle is having the anticipated effect. The question now is whether or not BSE can be completely eradicated. At present there is no evidence of lateral or maternal transmission, the occurrence of which would complicate the eradication process. Eradication therefore seems to be achievable, especially now that meat and bone meal has been recently banned from the diets of all farmed animals in the UK. In this review the aetiological role of meat and bone meal in the causation of BSE is discussed together with the epidemiological data and the results of studies on genetic susceptibility. The controversial theories relating to the nature of the causal agent, and strain-typing studies on BSE agent, are described. Current information on pathogenesis and diagnosis is presented. The occurrence of BSE in cattle outside the United Kingdom, and BSE-related disease in species other than cattle is also discussed.
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Affiliation(s)
- D M Taylor
- BBSRC & MRC Neuropathogenesis Unit, Institute for Animal Health, Edinburgh, UK
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41
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Schreuder BE, van Keulen LJ, Vromans ME, Langeveld JP, Smits MA. Preclinical test for prion diseases. Nature 1996; 381:563. [PMID: 8637589 DOI: 10.1038/381563a0] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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42
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Foster JD, Bruce M, McConnell I, Chree A, Fraser H. Detection of BSE infectivity in brain and spleen of experimentally infected sheep. Vet Rec 1996; 138:546-8. [PMID: 8782362 DOI: 10.1136/vr.138.22.546] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- J D Foster
- Institute for Animal Health, BBSRC and MRC Neuropathogenesis Unit, Edinburgh
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43
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Scott MR, Telling GC, Prusiner SB. Transgenetics and gene targeting in studies of prion diseases. Curr Top Microbiol Immunol 1996; 207:95-123. [PMID: 8575209 DOI: 10.1007/978-3-642-60983-1_8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- M R Scott
- Department of Neurology, University of California, San Francisco 94143-0518, USA
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44
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Affiliation(s)
- S B Prusiner
- Department of Neurology, University of California, San Francisco 94143-0518, USA
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45
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Biochemistry and Genetics of Prion Proteins. Eur J Med Chem 1995. [DOI: 10.1016/s0223-5234(23)00113-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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46
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Abstract
Scrapie was thought for many years to be caused by a virus. Enriching fractions from Syrian hamster (SHa) brain for scrapie infectivity led to the discovery of the prion protein (PrP). To date, no scrapie-specific nucleic acid has been found. As well as scrapie, prion diseases include bovine spongiform encephalopathy (BSE) of cattle, as well as Creutzfeldt-Jakob disease (CJD) and Gerstmann-Sträussler-Scheinker syndrome (GSS) of humans. Transgenic (Tg) mice expressing both SHa and mouse (Mo) PrP genes were used to probe the molecular basis of the species barrier and the mechanism of scrapie prion replication. The prion inoculum was found to dictate which prions are synthesized de novo, even though the cells express both PrP genes. Discovery of mutations in the PrP genes of humans with GSS and familial CJD established that prion diseases are both genetic and infectious. Tg mice expressing MoPrP with the GSS point mutation spontaneously develop neurologic dysfunction, spongiform degeneration and astrocytic gliosis. Inoculation of brain extracts prepared from these Tg(MoPrP-P101L) mice produced neurodegeneration in many of the recipient animals after prolonged incubation times. These and other results suggest that prions are devoid of foreign nucleic acid and are thus different from viruses and viroids. Studies on the structure of PrPSc and PrPC suggest that the difference is conformational. Whether one or more putative alpha-helices in PrPC are converted into beta-sheets during synthesis of PrPSc is unknown. Distinct prion isolates or 'strains' exhibit different patterns of PrPSc accumulation which are independent of incubation times. Whether variations in PrPSc conformation are responsible for prion diversity remains to be established. Prion studies have given new insights into the etiologies of infectious, sporadic and inherited degenerative diseases.
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Affiliation(s)
- S B Prusiner
- Department of Neurology, University of California, San Francisco 94143
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47
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Brugère-Picoux J, Brugère H. [Transmissible animal spongiform encephalopathies. Epidemiologic aspects]. Transfus Clin Biol 1994; 1:363-71. [PMID: 7812463 DOI: 10.1016/s1246-7820(06)80018-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
This article presents an update of data about the transmissible spongiform encephalopathies which affect some animal species, particularly bovine spongiform encephalopathy in Great britain and in other countries where this disease is sporadic. The genetic susceptibility of scrapie in sheep and the natural transmission of these spongiform encephalopathies are discussed. The control measures for public health and animal health are presented.
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48
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Affiliation(s)
- M Pocchiari
- Section of Persistent and Slow Virus Infections, Istituto Superiore di Sanità, Rome, Italy
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49
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Georgsson G, Gísladóttir E, Arnadóttir S. Quantitative assessment of the astrocytic response in natural scrapie of sheep. J Comp Pathol 1993; 108:229-40. [PMID: 8315052 DOI: 10.1016/s0021-9975(08)80287-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Scrapie of sheep and goats belongs to the spongiform encephalopathies, a term derived from the characteristic vacuolar degeneration in the central nervous system. Astrocytosis has been described, but a systematic quantitative study has not been made. Such a study is important in resolving the still controversial issues as to whether the astrocytic response is caused directly by the infectious agent or represents a secondary reaction to tissue damage. In this study the numbers of astrocytes in 12 sheep with scrapie and 12 healthy sheep of a similar age were assessed and compared. Sections from eight planes of the brain were immunostained with anti-glial fibrillary acidic protein (GFAP) for astrocytes and their numbers counted in 40 areas of 1 mm2. The main findings were as follows. (1) A significant increase of astrocytes was detected in sheep with scrapie. (2) Astrocytosis was not usually related to the severity of the characteristic vacuolar lesions, indicating that it was at least partly due to a direct effect of the infectious agent but was not a secondary response to the neuronal damage. (3) The astrocytic response varied considerably between individual affected sheep; this may have been due to differences in agent strains, host response, or both.
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Affiliation(s)
- G Georgsson
- Institute for Experimental Pathology, University of Iceland, Reykjavik
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50
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Williams ES, Young S. Neuropathology of chronic wasting disease of mule deer (Odocoileus hemionus) and elk (Cervus elaphus nelsoni). Vet Pathol 1993; 30:36-45. [PMID: 8442326 DOI: 10.1177/030098589303000105] [Citation(s) in RCA: 103] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The pathology of the central nervous system of nine mule deer (Odocoileus hemionus) and six elk (Cervus elaphus nelsoni) with chronic wasting disease, a spongiform encephalopathy of mule deer and elk, was studied by light microscopy. Lesions were similar in both species and were characterized by spongiform transformation of gray matter, intracytoplasmic vacuolation of neurons, neuronal degeneration and loss, astrocytic hypertrophy and hyperplasia, occurrence of amyloid plaques, and absence of significant inflammatory response. Distribution and severity of lesions were evaluated at 57 locations; there were only minor differences between deer and elk. Consistent, severe lesions occurred in olfactory tubercle and cortex, hypothalamus, and the parasympathetic vagal nucleus of deer, and sections examined from these regions would be sufficient to establish a diagnosis of chronic wasting disease. Lesions were milder in these locations in elk but were sufficiently apparent to be of diagnostic value. Other differences included increased severity of lesions in some thalamic nuclei in elk in contrast to deer, the occurrence of amyloid plaques demonstrable by hematoxylin and eosin and histochemical stains in deer in contrast to elk, and the presence of mild white matter lesions in elk but not in deer. Lesions of chronic wasting disease were qualitatively comparable to those of scrapie, bovine spongiform encephalopathy, transmissible mink encephalopathy, and the human spongiform encephalopathies. Topographic distribution and lesion severity of chronic wasting disease were most similar to those of scrapie and bovine spongiform encephalopathy. Duration of clinical disease did not significantly influence lesion distribution or severity in either species.
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Affiliation(s)
- E S Williams
- Department of Veterinary Sciences, University of Wyoming, Laramie
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