1
|
Fast C, Graham C, Kaatz M, Santiago-Mateo K, Kaatz T, MacPherson K, Balkema-Buschmann A, Ziegler U, Groschup MH, Czub S. Discrimination of Classical and Atypical BSE by a Distinct Immunohistochemical PrP Sc Profile. Pathogens 2023; 12:pathogens12020353. [PMID: 36839625 PMCID: PMC9965285 DOI: 10.3390/pathogens12020353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Revised: 02/13/2023] [Accepted: 02/15/2023] [Indexed: 02/22/2023] Open
Abstract
Bovine spongiform encephalopathy (BSE) belongs to the group of transmissible spongiform encephalopathies and is associated with the accumulation of a pathological isoform of the host-encoded glycoprotein, designated prion protein (PrPSc). Classical BSE (C-type) and two atypical BSE forms (L- and H-type) are known, and can be discriminated by biochemical characteristics. The goal of our study was to identify type-specific PrPSc profiles by using Immunohistochemistry. In our study, brain samples from 21 cattle, intracerebrally inoculated with C-, H-, and L-type BSE, were used. In addition, the corresponding samples from three orally C-type BSE infected animals were also included. From all animals, a lesion and PrPSc-profiles of six brain regions were determined. The lesion profile and the neuroanatomical distribution of PrPSc was highly consistent between the groups, but the immunohistochemical analysis revealed a distinct PrPSc profile for the different BSE-types, which included both the topographic and cellular pattern of PrPSc. This qualitative and quantitative analysis of PrPSc affected structures sheds new light into the pathogenesis of the different BSE types. Furthermore, immunohistochemical characterization is supported as an additional diagnostic tool in BSE surveillance programs, especially when only formalin-fixed tissue samples are available.
Collapse
Affiliation(s)
- Christine Fast
- Friedrich-Loeffler Institut/INEID, 17493 Insel Riems, Germany
- Correspondence: ; Tel.: +49-38351-71274
| | | | - Martin Kaatz
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | | | - Tammy Kaatz
- Canadian Food Inspection Agency, Lethbridge, AB T1J 3Z4, Canada
| | - Kendra MacPherson
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| | | | - Ute Ziegler
- Friedrich-Loeffler Institut/INEID, 17493 Insel Riems, Germany
| | | | - Stefanie Czub
- Canadian Food Inspection Agency, Lethbridge, AB T1J 3Z4, Canada
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 1N4, Canada
| |
Collapse
|
2
|
McNulty E, Nalls AV, Mellentine S, Hughes E, Pulscher L, Hoover EA, Mathiason CK. Comparison of conventional, amplification and bio-assay detection methods for a chronic wasting disease inoculum pool. PLoS One 2019; 14:e0216621. [PMID: 31071138 PMCID: PMC6508678 DOI: 10.1371/journal.pone.0216621] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 04/24/2019] [Indexed: 11/18/2022] Open
Abstract
Longitudinal studies of chronic wasting disease (CWD) in the native host have provided considerable understanding of how this prion disease continues to efficiently spread among cervid species. These studies entail great cost in animal, time and financial support. A variety of methods have emerged including transgenic mouse bioassay, western blot, enzyme-linked immunoassay (ELISA), immunohistochemistry (IHC), serial protein misfolding cyclic amplification (sPMCA) and real time quaking-induced conversion (RT-QuIC), that deepen our understanding of this and other protein misfolding disorders. To further characterize an inoculum source used for ongoing CWD studies and to determine how the readouts from each of these assays compare, we assayed a CWD-positive brain pool homogenate (CBP6) and a mouse dilutional bioassay of this homogenate using the above detection methods. We demonstrate that: (i) amplification assays enhanced detection of amyloid seeding activity in the CWD+ cervid brain pool to levels beyond mouse LD50, (ii) conventional detection methods (IHC and western blot) performed well in identifying the presence of PrPSc in terminal brain tissue yet lack sufficient detection sensitivity to identify all CWD-infected mice, and (iii) the incorporation of amplification assays enhanced detection of CWD-infected mice near the LD50. This cross-platform analysis provides a basis to calibrate the relative sensitivities of CWD detection assays.
Collapse
Affiliation(s)
- Erin McNulty
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Amy V. Nalls
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Samuel Mellentine
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Erin Hughes
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Laura Pulscher
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Edward A. Hoover
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Candace K. Mathiason
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
- * E-mail:
| |
Collapse
|
3
|
Adkin A, Horigan V, Rajanayagam B, Arnold M, Konold T, Spiropoulos J, Kelly L. Estimating the impact on food and edible materials of changing scrapie control measures: The scrapie control model. Prev Vet Med 2018; 158:51-64. [DOI: 10.1016/j.prevetmed.2018.07.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 06/28/2018] [Accepted: 07/02/2018] [Indexed: 11/27/2022]
|
4
|
Scano P, Rosa A, Incani A, Maestrale C, Santucciu C, Perra D, Vascellari S, Pani A, Ligios C. (1)H NMR brain metabonomics of scrapie exposed sheep. MOLECULAR BIOSYSTEMS 2016; 11:2008-16. [PMID: 25959287 DOI: 10.1039/c5mb00138b] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
While neurochemical metabolite modifications, determined by different techniques, have been diffusely reported in human and mice brains affected by transmissible spongiform encephalopathies (TSEs), this aspect has been little studied in the natural animal hosts with the same pathological conditions so far. Herein, we investigated, by high resolution (1)H NMR spectroscopy and multivariate statistical data analysis, the brain metabolite profile of sheep exposed to a scrapie agent in a naturally affected flock. On the basis of clinical examinations and western blotting analysis for the pathological prion protein (PrP(Sc)) in brain tissues, sheep were catalogued as not infected (H), infected with clinical signs (S), and infected without clinical signs (A). By discriminant analysis of spectral data, comparing S vs. H, we found a different metabolite distribution, with inosine, cytosine, creatine, and lactate being higher in S than in H brains, while the branched chain amino acids (leucine, isoleucine, and valine), phenylalanine, uracil, tyrosine, gamma-amino butyric acid, total aspartate (aspartate + N-acetyl aspartate) being lower in S. By a soft independent modelling of class analogy approach, 1 out of 3 A samples was assigned to class H. Furthermore, A brains were found to be higher in choline and choline-containing compounds. By means of partial least squares regression, an excellent correlation was found between the PrP(Sc) amount and the (1)H NMR metabolite profile of infected (S and A) sheep, and the metabolite mostly correlated with PrP(Sc) was alanine. The overall results, obtained using different chemometric tools, were able to describe a brain metabolite profile of infected sheep with and without clinical signs, compared to healthy ones, and indicated alanine as a biomarker for PrP(Sc) amounts in scrapie brains.
Collapse
Affiliation(s)
- Paola Scano
- Department of Chemical and Geological Sciences, University of Cagliari, Monserrato, Italy.
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Lack of prion accumulation in lymphoid tissues of PRNP ARQ/ARR sheep intracranially inoculated with the agent of scrapie. PLoS One 2014; 9:e108029. [PMID: 25233232 PMCID: PMC4169493 DOI: 10.1371/journal.pone.0108029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Accepted: 08/24/2014] [Indexed: 11/20/2022] Open
Abstract
Sheep scrapie is a transmissible spongiform encephalopathy that can be transmitted horizontally. The prion protein gene (PRNP) profoundly influences the susceptibility of sheep to the scrapie agent and the tissue levels and distribution of PrPSc in affected sheep. The purpose of this study was to compare the survival time and PrPSc tissue distribution in sheep with highly resistant and highly susceptible PRNP genotypes after intracranial inoculation of the agent of scrapie. Five sheep each of genotype VRQ/VRQ, VRQ/ARR or ARQ/ARR were inoculated. Sheep were euthanized when clinical signs of scrapie became severe. Clinical signs, microscopic lesions, and western blot profiles were uniform across genotypes and consistent with manifestations of classical scrapie. Mean survival time differences were associated with the 171 polymorphic site with VRQ/VRQ sheep surviving 18 months, whereas VRQ/ARR and ARQ/ARR sheep survived 60 and 56 months, respectively. Labeling of PrPSc by immunohistochemistry revealed similar accumulations in central nervous system tissues regardless of host genotype. Immunoreactivity for PrPSc in lymphoid tissue was consistently abundant in VRQ/VRQ, present but confined to tonsil or retropharyngeal lymph node in 4/5 VRQ/ARR, and totally absent in ARQ/ARR sheep. The results of this study demonstrate the susceptibility of sheep with the ARQ/ARR genotype to scrapie by the intracranial inoculation route with PrPSc accumulation in CNS tissues, but prolonged incubation times and lack of PrPSc in lymphoid tissue.
Collapse
|
6
|
Scientific Opinion on the scrapie situation in the EU after 10 years of monitoring and control in sheep and goats. EFSA J 2014. [DOI: 10.2903/j.efsa.2014.3781] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
7
|
Affiliation(s)
- V. Beringue
- UR892 Virologie et Immunologie Moléculaires Centre de Recherche de Jouy-en-Josas F-78352 Jouy-en-Josas, France
| | - O. Andreoletti
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles 31076 Toulouse, France
| |
Collapse
|
8
|
Rosa A, Scano P, Incani A, Pilla F, Maestrale C, Manca M, Ligios C, Pani A. Lipid profiles in brains from sheep with natural scrapie. Chem Phys Lipids 2013; 175-176:33-40. [DOI: 10.1016/j.chemphyslip.2013.08.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 08/01/2013] [Indexed: 01/03/2023]
|
9
|
Corbière F, Chauvineau-Perrin C, Lacroux C, Lugan S, Costes P, Thomas M, Brémaud I, Chartier C, Barillet F, Schelcher F, Andréoletti O. The limits of test-based scrapie eradication programs in goats. PLoS One 2013; 8:e54911. [PMID: 23372789 PMCID: PMC3553010 DOI: 10.1371/journal.pone.0054911] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 12/19/2012] [Indexed: 12/21/2022] Open
Abstract
Small ruminant post-mortem testing programs were initially designed for monitoring the prevalence of prion disease. They are now considered as a potential alternative to genetic selection for eradicating/controlling classical scrapie at population level. If such policy should be implemented, its success would be crucially dependent on the efficiency of the surveillance system used to identify infected flocks. In this study, we first determined the performance of post-mortem classical scrapie detection in eight naturally affected goat herds (total n = 1961 animals) according to the age at culling. These results provided us with necessary parameters to estimate, through a Monte Carlo simulation model, the performance of scrapie detection in a commercial population. According to this model, whatever the number of tests performed, post mortem surveillance will have limited success in identifying infected herds. These data support the contention that scrapie eradication programs relying solely on post mortem testing in goats will probably fail. Considering the epidemiological and pathological similarities of scrapie in sheep and goats, the efficiency of scrapie surveillance in both species is likely to be similar.
Collapse
Affiliation(s)
- Fabien Corbière
- UMR 1225 INRA-ENVT Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire, Toulouse, France
| | | | - Caroline Lacroux
- UMR 1225 INRA-ENVT Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire, Toulouse, France
| | - Séverine Lugan
- UMR 1225 INRA-ENVT Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire, Toulouse, France
| | - Pierrette Costes
- UMR 1225 INRA-ENVT Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire, Toulouse, France
| | - Myriam Thomas
- ANSES, Laboratoire d’études et recherches caprines, Niort, France
| | - Isabelle Brémaud
- ANSES, Laboratoire d’études et recherches caprines, Niort, France
| | | | - Francis Barillet
- INRA, UR 631, Station d’Amélioration Génétique des Animaux, Castanet-Tolosan, France
| | - François Schelcher
- UMR 1225 INRA-ENVT Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire, Toulouse, France
| | - Olivier Andréoletti
- UMR 1225 INRA-ENVT Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire, Toulouse, France
- * E-mail:
| |
Collapse
|
10
|
|
11
|
Marruchella G, Ligios C, Di Guardo G. Age, scrapie status, PrP genotype and follicular dendritic cells in ovine ileal Peyer’s patches. Res Vet Sci 2012; 93:853-6. [DOI: 10.1016/j.rvsc.2011.09.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2011] [Revised: 08/23/2011] [Accepted: 09/07/2011] [Indexed: 10/17/2022]
|
12
|
Comparative performance of three TSE rapid tests for surveillance in healthy sheep affected by scrapie. J Virol Methods 2011; 173:161-8. [DOI: 10.1016/j.jviromet.2011.01.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2010] [Revised: 12/29/2010] [Accepted: 01/11/2011] [Indexed: 11/21/2022]
|
13
|
Joint Scientific Opinion on any possible epidemiological or molecular association between TSEs in animals and humans. EFSA J 2011. [DOI: 10.2903/j.efsa.2011.1945] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
|
14
|
|
15
|
Abstract
Prions are misfolded proteins that are infectious and naturally transmitted, causing a fatal neurological disease in humans and animals. Prion shedding routes have been shown to be modified by inflammation in excretory organs, such as the kidney. Here, we show that sheep with scrapie and lentiviral mastitis secrete prions into the milk and infect nearly 90% of naïve suckling lambs. Thus, lentiviruses may enhance prion transmission, conceivably sustaining prion infections in flocks for generations. This study also indicates a risk of prion spread to sheep and potentially to other animals through dietary exposure to pooled sheep milk or milk products.
Collapse
|
16
|
An assessment of the efficiency of PrPsc detection in rectal mucosa and third-eyelid biopsies from animals infected with scrapie. Vet Microbiol 2010; 147:237-43. [PMID: 20685048 DOI: 10.1016/j.vetmic.2010.06.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2009] [Revised: 06/21/2010] [Accepted: 06/29/2010] [Indexed: 12/30/2022]
Abstract
In classical scrapie, detection of PrPsc on lymphoreticular system is used for the in vivo and post mortem diagnosis of the disease. However, the sensitivity of this methodology is not well characterised because the magnitude and duration of lymphoid tissue involvement can vary considerably. The aim of the present study was to evaluate the efficiency of detecting PrPsc in rectal mucosa and third-eyelid biopsies. A total of 474 genetically susceptible sheep and 24 goats from three scrapie infected flocks were included in this study. A sample from rectal mucosa and a sample from third-eyelid lymphoid tissue were collected from each animal. Biopsy samples were fixed in formaldehyde and processed for immunohistochemical examination. Animals with negative biopsy results were studied more closely through a post mortem examination of central nervous and lymphoreticular systems and if there was a positive result, additional biopsy sections were further tested. The sensitivity of rectal mucosa and third-eyelid assays were 36% and 40% respectively on initial examination but increased to 48% and 44% respectively after retesting. The results of this field study show a high percentage of infected animals that do not have detectable levels of PrPsc in the biopsied lymphoid tissue, due mainly to the relatively high number of animals with minimal or no involvement of lymphoid tissue in the pathogenesis of the disease.
Collapse
|
17
|
Santucciu C, Maestrale C, Madau L, Attene S, Cancedda MG, Demontis F, Tilocca MG, Saba M, Macciocu S, Carta A, Ligios C. Association of N176K and L141F dimorphisms of the PRNP gene with lack of pathological prion protein deposition in placentas of naturally and experimentally scrapie-affected ARQ/ARQ sheep. J Gen Virol 2010; 91:2402-7. [PMID: 20463148 DOI: 10.1099/vir.0.021188-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The placenta is important in the horizontal transmission of the aetiological agent in scrapie-affected sheep. It has been demonstrated that the placentas of fetuses carrying the dimorphism Q171R of the PRNP gene is resistant to pathological prion protein (PrP(Sc)) accumulation in the placenta. To test whether other PRNP polymorphisms are associated with a lack of placental PrP(Sc) deposition, we carried out a study on 26 naturally and 11 experimentally scrapie-affected ewes with or without clinical signs. PrP(Sc) was detected in the placenta of ARQ/ARQ(wild type) fetuses by Western blot and immunohistochemical analysis, but not in ARQN(176)/ARQK(176) or, as expected, ARQ/ARR samples. Furthermore, three of four AL(141)RQ/AF(141)RQ placentas were also PrP(Sc) negative, suggesting that the dimorphism at codon 141 may also mediate placental deposition of PrP(Sc). This finding demonstrates for the first time that fetal PRNP polymorphisms, other than those at codon 171, are associated with the lack of placental deposition of PrP(Sc).
Collapse
Affiliation(s)
- Cinzia Santucciu
- Istituto Zooprofilattico Sperimentale della Sardegna, 07100 Sassari, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Tabouret G, Lacroux C, Lugan S, Costes P, Corbière F, Weisbecker JL, Schelcher F, Andréoletti O. Relevance of oral experimental challenge with classical scrapie in sheep. J Gen Virol 2010; 91:2139-2144. [PMID: 20444991 DOI: 10.1099/vir.0.021311-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Oral inoculation is currently considered as the best approach to mimic natural TSE contamination in ruminants. In this study, we compared the timing of abnormal prion protein (PrP(Sc)) dissemination and accumulation in the organism of susceptible sheep either orally inoculated or naturally infected with classical scrapie. Both animal groups shared a similar PrP(Sc) dissemination scheme and accumulation dynamics in lymphoid tissues. However, orally challenged animals displayed an earlier neuro-invasion and a dramatically shorter incubation period than naturally exposed sheep. No differences were observed between the groups with regards to the neuro-invasion route. These results unambiguously indicate that oral inoculation can have an impact on both the earliness of neuro-invasion and the incubation period. They also support the statement that oral inoculation is a relevant model for investigating transmissible spongiform encephalopathy pathogenesis. Nevertheless, data obtained under such experimental conditions should be used with some caution.
Collapse
Affiliation(s)
- Guillaume Tabouret
- UMR INRA ENVT 1225, Interactions Hôtes-Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France
| | - Caroline Lacroux
- UMR INRA ENVT 1225, Interactions Hôtes-Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France
| | - Séverine Lugan
- UMR INRA ENVT 1225, Interactions Hôtes-Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France
| | - Pierrette Costes
- UMR INRA ENVT 1225, Interactions Hôtes-Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France
| | - Fabien Corbière
- UMR INRA ENVT 1225, Interactions Hôtes-Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France
| | | | - François Schelcher
- UMR INRA ENVT 1225, Interactions Hôtes-Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France
| | - Olivier Andréoletti
- UMR INRA ENVT 1225, Interactions Hôtes-Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 Chemin des Capelles, 31076 Toulouse, France
| |
Collapse
|
19
|
Salazar E, Monleón E, Bolea R, Acín C, Pérez M, Alvarez N, Leginagoikoa I, Juste R, Minguijón E, Reina R, Glaria I, Berriatua E, de Andrés D, Badiola JJ, Amorena B, Luján L. Detection of PrPSc in lung and mammary gland is favored by the presence of Visna/maedi virus lesions in naturally coinfected sheep. Vet Res 2010; 41:58. [PMID: 20423698 PMCID: PMC2881419 DOI: 10.1051/vetres/2010030] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2010] [Accepted: 04/27/2010] [Indexed: 11/14/2022] Open
Abstract
There are few reports on the pathogenesis of scrapie (Sc) and Visna/maedi virus (VMV) coinfections. The aim of this work was to study in vivo as well as post mortem both diseases in 91 sheep. Diagnosis of Sc and VMV infections allowed the distribution of animals into five groups according to the presence (+) or absence (−) of infection by Sc and VMV: Sc−/VMV−, Sc−/VMV+, Sc+/VMV− and Sc+/VMV+. The latter was divided into two subgroups, with and without VMV-induced lymphoid follicle hyperplasia (LFH), respectively. In both the lung and mammary gland, PrPSc deposits were found in the germinal center of hyperplasic lymphoid follicles in the subgroup of Sc+/VMV+ having VMV-induced LFH. This detection was always associated with (and likely preceded by) PrPSc observation in the corresponding lymph nodes. No PrPSc was found in other VMV-associated lesions. Animals suffering from scrapie had a statistically significantly lower mean age than the scrapie free animals at the time of death, with no apparent VMV influence. ARQ/ARQ genotype was the most abundant among the 91 ewes and the most frequent in scrapie-affected sheep. VMV infection does not seem to influence the scrapie risk group distribution among animals from the five groups established in this work. Altogether, these data indicate that certain VMV-induced lesions can favor PrPSc deposits in Sc non-target organs such as the lung and the mammary gland, making this coinfection an interesting field that warrants further research for a better comprehension of the pathogenesis of both diseases.
Collapse
Affiliation(s)
- Eider Salazar
- Department of Animal Pathology, Veterinary Faculty, University of Zaragoza, 177 Miguel Servet street, 50013 Zaragoza, Spain
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Maestrale C, Carta A, Attene S, Galistu A, Santucciu C, Cancedda MG, Saba M, Sechi S, Patta C, Bandino E, Ligios C. p.Asn176Lys and p.Met137Thr dimorphisms of the PRNP gene significantly decrease the susceptibility to classical scrapie in ARQ/ARQ sheep. Anim Genet 2009; 40:982-5. [PMID: 19706028 DOI: 10.1111/j.1365-2052.2009.01943.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, we investigated the susceptibility to scrapie of Sarda breed sheep carrying the genotype ARQ/ARQ with additional polymorphisms at the PRNP gene. To do this, we examined 256 scrapie-affected sheep and 320 flock-mate negative controls from 24 flocks. Logistic regression analysis demonstrated that sheep carrying the ARQ/ARQ genotype with additional dimorphisms had lower risk of becoming scrapie affected when compared with those with ARQ/ARQ(wildtype) genotype. ARQ/ARQ genotypes that were detected with heterozygous or homozygous p.Asn176Lys and p.Met137Thr dimorphisms were associated with the lowest susceptibility to the disease. A significant lower risk was also associated with the p.Arg154His dimorphism, while p.Leu141Phe had a protective effect that was not statistically significant.
Collapse
Affiliation(s)
- C Maestrale
- Istituto Zooprofilattico Sperimentale della Sardegna, Via Duca degli Abruzzi 8, 07100 Sassari, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Sisó S, Jeffrey M, González L. Neuroinvasion in sheep transmissible spongiform encephalopathies: the role of the haematogenous route. Neuropathol Appl Neurobiol 2009; 35:232-46. [DOI: 10.1111/j.1365-2990.2008.00978.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
|
22
|
Marruchella G, Ligios C, Baffoni M, Cancedda MG, Demontis F, Donatucci G, Chiocchetti R, Clavenzani P, Lalatta-Costerbosa G, Di Guardo G. Ileal tract and Peyer's patch innervation in scrapie-free versus scrapie-affected ovines. Arch Virol 2009; 154:709-14. [PMID: 19330284 DOI: 10.1007/s00705-009-0361-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Accepted: 03/09/2009] [Indexed: 12/28/2022]
Abstract
Ileal Peyer's patches (PPs) are involved early during sheep scrapie infection. This study qualitatively and semi-quantitatively evaluated ileal tract and PP innervation in 29 Sarda ovines of different age, PrP genotype and scrapie status. A prominent network of fibres was detected within PPs, mainly located in interfollicular lymphoid and stromal components. Intrafollicular fibres were rarely observed, with no apparent differences between scrapie-free and scrapie-affected animals, or among ovines carrying different PrP genotypes. In adult sheep, independent of their scrapie status, nerve fibres could be detected infrequently, close to the follicle-associated epithelium. Fibres were also detected within newly formed follicles and intrafollicular microgranulomas.
Collapse
Affiliation(s)
- G Marruchella
- Department of Comparative Biomedical Sciences, University of Teramo, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Validation of use of rectoanal mucosa-associated lymphoid tissue for immunohistochemical diagnosis of chronic wasting disease in white-tailed deer (Odocoileus virginianus). J Clin Microbiol 2009; 47:1412-7. [PMID: 19261781 DOI: 10.1128/jcm.02209-08] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The examination of rectoanal mucosa-associated lymphoid tissue (RAMALT) biopsy specimens for the diagnosis of transmissible spongiform encephalopathies has been described in sheep, elk, and small numbers of mule and white-tailed deer. Previous sample numbers have been too small to validate examination of this type of tissue as a viable antemortem diagnostic test. In this study, we examined RAMALT collected postmortem from 76 white-tailed deer removed from a farm in Wisconsin known to be affected by chronic wasting disease (CWD) and from 210 free-ranging white-tailed deer harvested from an area in Wisconsin where the overall prevalence of CWD among the deer was approximately 4 to 6%. The results of immunohistochemical (IHC) staining of the RAMALT sections were compared to the results of IHC staining of sections from the brain stem at the convergence of the dorsal motor nucleus of the vagus nerve, sections of the medial retropharyngeal lymph nodes (RLNs), and sections of tonsil (sections of tonsil only from captive animals were tested). The sensitivities of the IHC staining test with RAMALT sections were 81% for the captive animals and 91% for the free-ranging animals. False-negative results were usually associated with early infection, indicated by a low intensity of immunostaining in the obex and/or a polymorphism at PRNP codon 96. While the RLN remains the tissue of choice for use for the diagnosis of CWD in white-tailed deer, the results of the present study further support the use of RAMALTs collected antemortem as an adjunct to testing of tonsil biopsy specimens and surveillance by necropsy for the screening of farmed deer which have been put at risk through environmental exposure or exposure to deer with CWD.
Collapse
|
24
|
Lacroux C, Simon S, Benestad SL, Maillet S, Mathey J, Lugan S, Corbière F, Cassard H, Costes P, Bergonier D, Weisbecker JL, Moldal T, Simmons H, Lantier F, Feraudet-Tarisse C, Morel N, Schelcher F, Grassi J, Andréoletti O. Prions in milk from ewes incubating natural scrapie. PLoS Pathog 2008; 4:e1000238. [PMID: 19079578 PMCID: PMC2587713 DOI: 10.1371/journal.ppat.1000238] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Accepted: 11/12/2008] [Indexed: 11/19/2022] Open
Abstract
Since prion infectivity had never been reported in milk, dairy products originating from transmissible spongiform encephalopathy (TSE)-affected ruminant flocks currently enter unrestricted into the animal and human food chain. However, a recently published study brought the first evidence of the presence of prions in mammary secretions from scrapie-affected ewes. Here we report the detection of consistent levels of infectivity in colostrum and milk from sheep incubating natural scrapie, several months prior to clinical onset. Additionally, abnormal PrP was detected, by immunohistochemistry and PET blot, in lacteal ducts and mammary acini. This PrP(Sc) accumulation was detected only in ewes harbouring mammary ectopic lymphoid follicles that developed consequent to Maedi lentivirus infection. However, bioassay revealed that prion infectivity was present in milk and colostrum, not only from ewes with such lympho-proliferative chronic mastitis, but also from those displaying lesion-free mammary glands. In milk and colostrum, infectivity could be recovered in the cellular, cream, and casein-whey fractions. In our samples, using a Tg 338 mouse model, the highest per ml infectious titre measured was found to be equivalent to that contained in 6 microg of a posterior brain stem from a terminally scrapie-affected ewe. These findings indicate that both colostrum and milk from small ruminants incubating TSE could contribute to the animal TSE transmission process, either directly or through the presence of milk-derived material in animal feedstuffs. It also raises some concern with regard to the risk to humans of TSE exposure associated with milk products from ovine and other TSE-susceptible dairy species.
Collapse
Affiliation(s)
- Caroline Lacroux
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Stéphanie Simon
- CEA, Service de Pharmacologie et d'Immunoanalyse, IBiTec-S, DSV, CEA/Saclay, Gif sur Yvette, France
| | | | - Séverine Maillet
- CEA, Service de Pharmacologie et d'Immunoanalyse, IBiTec-S, DSV, CEA/Saclay, Gif sur Yvette, France
| | - Jacinthe Mathey
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Séverine Lugan
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Fabien Corbière
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Hervé Cassard
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Pierrette Costes
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Dominique Bergonier
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | | | | | - Hugh Simmons
- VLA Weybridge, New Haw, Addlestone, Surrey, United Kingdom
| | | | - Cécile Feraudet-Tarisse
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
- CEA, Service de Pharmacologie et d'Immunoanalyse, IBiTec-S, DSV, CEA/Saclay, Gif sur Yvette, France
| | - Nathalie Morel
- CEA, Service de Pharmacologie et d'Immunoanalyse, IBiTec-S, DSV, CEA/Saclay, Gif sur Yvette, France
| | - François Schelcher
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Jacques Grassi
- CEA, Service de Pharmacologie et d'Immunoanalyse, IBiTec-S, DSV, CEA/Saclay, Gif sur Yvette, France
| | - Olivier Andréoletti
- UMR INRA ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
- * E-mail:
| |
Collapse
|
25
|
TSE risk assessment from carcasses of ovine and caprine animals below 6 months of age from TSE infected flocks intended for human consumption ‐ Scientific Opinion of the Panel on Biological Hazards. EFSA J 2008; 6:719. [DOI: 10.2903/j.efsa.2008.719] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
|
26
|
Konold T, Moore SJ, Bellworthy SJ, Simmons HA. Evidence of scrapie transmission via milk. BMC Vet Res 2008; 4:14. [PMID: 18397513 PMCID: PMC2374774 DOI: 10.1186/1746-6148-4-14] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Accepted: 04/08/2008] [Indexed: 11/10/2022] Open
Abstract
Background The risk of scrapie infection increases with increased duration and proximity of contact between sheep at lambing. Scrapie infectivity has not been detected in milk but cellular prion protein, the precursor of disease-associated prion protein PrPd, has been found in milk from ruminants. To determine whether milk is able to transmit scrapie, 18 lambs with a prion protein genotype associated with high susceptibility to scrapie (VRQ/VRQ) were fed milk from twelve scrapie-affected ewes of the same genotype, and 15 VRQ/VRQ sheep reared on scrapie-free dams served as controls. Results Three lambs fed milk from scrapie-affected ewes were culled due to intercurrent diseases at 43, 44 and 105 days of age respectively, and PrPd was detected in the distal ileum of the first two lambs, whilst PrPd was not found in lymphoreticular tissues in the third lamb. A control lamb, housed in a separate pen and culled at 38 days of age, was also negative for PrPd in a range of tissues. Samples of recto-anal mucosa associated lymphoid tissue collected from the remaining 15 live lambs at seven months of age (between five to seven months after mixing) were positive for PrPd in the scrapie milk recipients, whereas PrPd was not detected in the remaining 14 controls at that time. A subsequent sample collected from control lambs revealed PrPd accumulation in two of five lambs eight months after mixing with scrapie milk recipients suggestive of an early stage of infection via lateral transmission. By contrast, the control sheep housed in the same building but not mixed with the scrapie milk recipients were still negative for PrPd. Conclusion The presence of PrPd in distal ileum and rectal mucosa indicates transmission of scrapie from ewe to lamb via milk (or colostrum) although it is not yet clear if such cases would go on to develop clinical disease. The high level of infection in scrapie-milk recipients revealed by rectal mucosal testing at approximately seven months of age may be enhanced or supplemented by intra-recipient infection as these lambs were mixed together after feeding with milk from scrapie-affected ewes and we also observed lateral transmission from these animals to lambs weaned from scrapie-free ewes.
Collapse
Affiliation(s)
- Timm Konold
- Neuropathology, Veterinary Laboratories Agency Weybridge, New Haw, Addlestone, Surrey KT15 3NB, UK.
| | | | | | | |
Collapse
|
27
|
High incidence of subclinical infection of lymphoid tissues in scrapie-affected sheep flocks. Arch Virol 2008; 153:637-44. [PMID: 18227967 DOI: 10.1007/s00705-008-0035-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2007] [Accepted: 12/27/2007] [Indexed: 10/22/2022]
Abstract
Prion diseases are characterized by a long incubation period. In scrapie, sheep may incubate and spread the infection for several years before clinical signs evolve. We have previously studied the occurrence of subclinical infection in the brain. Now, we have studied the occurrence of subclinical infection in the brain and several lymphoid tissues in two scrapie-affected Icelandic sheep flocks by immunohistochemistry for PrP(Sc), a molecular marker for infectivity, and correlated this with results of PrP genotyping. At culling, one flock had one confirmed scrapie case, while the other flock had two. Analysis of 106 asymptomatic sheep by immunostaining for PrP(Sc) revealed that the incidence of subclinical infection was 58.3% in one flock and 42.5% in the other. PrP(Sc) was only detected in lymphoid tissues. The youngest positive sheep were 4 months old. PrP genotyping showed that over 90% of the sheep were of a genotype which is moderately sensitive to infection and may delay neuroinvasion. Our results show that asymptomatic sheep may spread the infection during the long incubation period of several years, which constitutes an important obstacle in the eradication of scrapie. Our findings indicate that contamination of the environment plays an important part in sustaining the infection.
Collapse
|
28
|
Marruchella G, Ligios C, Albanese V, Cancedda MG, Madau L, Lalatta-Costerbosa G, Mazzoni M, Clavenzani P, Chiocchetti R, Sarli G, De Grossi L, Agrimi U, Aguzzi A, Di Guardo G. Enteroglial and neuronal involvement without apparent neuron loss in ileal enteric nervous system plexuses from scrapie-affected sheep. J Gen Virol 2007; 88:2899-2904. [PMID: 17872545 DOI: 10.1099/vir.0.82907-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The enteric nervous system (ENS) probably plays a dominant role in sheep scrapie pathogenesis, but little is known about the cell types involved. We investigated the ileal myenteric and submucosal plexuses of four naturally and four orally experimentally scrapie-affected ARQ/ARQ Sarda sheep, as well as those of 12 healthy-control Sarda sheep carrying different PrP genotypes. All scrapie-affected animals, euthanized at clinical-disease end stage, showed PrPd deposition within enteric glial cells (EGCs) and calbindin-immunoreactive (CALB-IR) and neuronal nitric oxide synthase (nNOS)-IR neurons. Whole-mount investigations revealed no significant differences between the densities of total, CALB-IR and nNOS-IR neurons in scrapie-affected versus healthy sheep, irrespective of PrP genotype. Our results suggest that EGCs and CALB-IR and nNOS-IR neurons are probably involved in the pathogenesis of natural and oral experimental sheep scrapie. Furthermore, the infectious agent may be less pathogenic towards ENS neurons than it is towards central nervous system neurons.
Collapse
Affiliation(s)
- Giuseppe Marruchella
- Department of Comparative Biomedical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy
| | - Ciriaco Ligios
- Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy
| | - Valeria Albanese
- Department of Comparative Biomedical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy
| | | | - Laura Madau
- Istituto Zooprofilattico Sperimentale della Sardegna, Sassari, Italy
| | - Giovanna Lalatta-Costerbosa
- Department of Veterinary Morphophysiology and Animal Productions, Faculty of Veterinary Medicine, University of Bologna, Ozzano Emilia (Bologna), Italy
| | - Maurizio Mazzoni
- Department of Veterinary Morphophysiology and Animal Productions, Faculty of Veterinary Medicine, University of Bologna, Ozzano Emilia (Bologna), Italy
| | - Paolo Clavenzani
- Department of Veterinary Morphophysiology and Animal Productions, Faculty of Veterinary Medicine, University of Bologna, Ozzano Emilia (Bologna), Italy
| | - Roberto Chiocchetti
- Department of Veterinary Morphophysiology and Animal Productions, Faculty of Veterinary Medicine, University of Bologna, Ozzano Emilia (Bologna), Italy
| | - Giuseppe Sarli
- Department of Veterinary Public Health and Animal Pathology, Division of Veterinary Pathology, Faculty of Veterinary Medicine, University of Bologna, Ozzano Emilia (Bologna), Italy
| | - Luigi De Grossi
- Istituto Zooprofilattico Sperimentale delle Regioni Lazio e Toscana, Viterbo, Italy
| | - Umberto Agrimi
- Istituto Superiore di Sanità, Department of Food Safety and Veterinary Public Health, Rome, Italy
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zurich, Zurich, Switzerland
| | - Giovanni Di Guardo
- Department of Comparative Biomedical Sciences, Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy
| |
Collapse
|
29
|
Dorban G, Defaweux V, Demonceau C, Flandroy S, Van Lerberghe PB, Falisse-Poirrier N, Piret J, Heinen E, Antoine N. Interaction between dendritic cells and nerve fibres in lymphoid organs after oral scrapie exposure. Virchows Arch 2007; 451:1057-65. [PMID: 17823814 DOI: 10.1007/s00428-007-0476-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Revised: 07/12/2007] [Accepted: 07/13/2007] [Indexed: 01/16/2023]
Abstract
In transmissible spongiform encephalopathies (TSEs), the infectious agent, called PrPsc, an abnormal isoform of the cellular prion protein, accumulates and replicates in lymphoid organs before affecting the nervous system. To clarify the cellular requirements for the neuroinvasion of the scrapie agent from the lymphoid organs to the central nervous system, we have studied, by confocal microscopy, the innervations within Peyer's patches, mesenteric lymph nodes and the spleen of mice in physiological conditions and after oral exposure to prion. Contacts between nerve fibres and PrPsc-associated cells, dendritic cells (DCs) and follicular dendritic cells (FDCs), were evaluated in preclinical prion-infected mice. Using a double immunolabelling strategy, we demonstrated the lack of innervation of PrPsc-accumulating cells (FDCs). Contacts between nerve fibers and PrPsc-propagating cells (DCs) were detected in T-cell zones and cell-trafficking areas. This supports, for the first time, the possible implication of dendritic cells in the prion neuroinvasion process.
Collapse
Affiliation(s)
- Gauthier Dorban
- Human Histology, Immunology Center, Faculty of Medicine, University of Liège, CHU, Avenue de l'hôpital, Tour de pharmacie +4, 4000 Liège, Belgium.
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Vidal E, Tortosa R, Costa C, Benavides J, Francino O, Sánchez-Robert E, Pérez V, Pumarola M. Lack of PrP(sc) immunostaining in intracranial ectopic lymphoid follicles in a sheep with concomitant non-suppurative encephalitis and Nor98-like atypical scrapie: a case report. Vet J 2007; 177:283-8. [PMID: 17574883 DOI: 10.1016/j.tvjl.2007.04.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2007] [Revised: 03/09/2007] [Accepted: 04/04/2007] [Indexed: 11/19/2022]
Abstract
During active surveillance for transmissible spongiform encephalopathies (TSEs) in sheep, an initial reactor was detected using a rapid test on a brain sample. Immunohistochemistry confirmed an atypical TSE presentation that closely resembled the previously described Nor98 cases. Sequencing of the prnp gene confirmed the ARQ/AHQ genotype with the L141F mutation at codon 141 associated with this phenotype. The head, including the brain and cranial lymphoid tissues, was sampled and examined thoroughly. Non-purulent encephalitis, with ectopic lymphoid follicle formation within the brain, was diagnosed concomitant to the TSE. When scrapie-associated prion protein (PrP(sc)) deposition was studied by immunohistochemistry there was a noticeable lack of lymphotropism. The distribution of PrP(sc) in the brain differed considerably from that of classical scrapie cases. Astrogliosis and microgliosis were demonstrated by histochemical procedures.
Collapse
Affiliation(s)
- E Vidal
- Priocat Laboratory, CReSA, Autonomous University of Barcelona, Bellaterra (Cerdanyola del Vallès), Spain
| | | | | | | | | | | | | | | |
Collapse
|
31
|
Hunter N. Scrapie: uncertainties, biology and molecular approaches. Biochim Biophys Acta Mol Basis Dis 2007; 1772:619-28. [PMID: 17560089 DOI: 10.1016/j.bbadis.2007.04.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2006] [Revised: 04/23/2007] [Accepted: 04/26/2007] [Indexed: 10/23/2022]
Abstract
The study of the biology of scrapie in sheep is irretrievably associated with the genetics of the PrP gene in sheep. Control of susceptibility and resistance is so closely linked to certain alleles of the sheep PrP gene that no review on scrapie can avoid PrP genetics. Before the importance of PrP protein was discovered and before the influence of the gene itself on disease incidence was understood, it was clear there were some sheep which were more susceptible to natural scrapie than others and that this feature was heritable. These early observations have led to the development and use of PrP genotyping in sheep in what is probably the biggest genetic selection process ever attempted. The accompanying increase in surveillance has also discovered a novel type of scrapie, the subject of much speculation about its origin.
Collapse
Affiliation(s)
- Nora Hunter
- Neuropathogenesis Unit, Roslin Institute, West Mains Road, Edinburgh, Scotland, UK.
| |
Collapse
|
32
|
Abstract
Scrapie is the longest known and most widely spread of the transmissible spongiform encephalopathies and remains the model for much of the research regarding these diseases. Because scrapie is a reportable disease and the subject of an active eradication program in the United States, veterinary practitioners should have a basic understanding of the disease.
Collapse
Affiliation(s)
- Marie S Bulgin
- Department of Animal and Veterinary Science, Caine Veterinary Teaching Center, University of Idaho, Caldwell, ID 83607, USA
| | | |
Collapse
|
33
|
Lalatta-Costerbosa G, Mazzoni M, Clavenzani P, Di Guardo G, Mazzuoli G, Marruchella G, De Grossi L, Agrimi U, Chiocchetti R. Nitric oxide synthase immunoreactivity and NADPH-d histochemistry in the enteric nervous system of Sarda breed sheep with different PrP genotypes in whole-mount and cryostat preparations. J Histochem Cytochem 2007; 55:387-401. [PMID: 17210925 DOI: 10.1369/jhc.6a7052.2007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Until now, significant differences in the neurochemical pattern of enteric neurons have been demonstrated in all species studied; however, some strong similarities also occur across species, such as the occurrence of nitric oxide synthase immunoreactivity (NOS-IR) in inhibitory motor neurons to muscle. In consideration of the insufficient data regarding the enteric nervous system (ENS) of sheep, we investigated the myenteric plexus and submucosal plexus of the ovine ileum. Since the pivotal role of the ENS in the early pathogenesis of sheep scrapie, the "prototype" of prion diseases, has been suggested, we have focused our observations also on the host's PrP genotype. We have studied the morphology and distribution of NOS-IR neurons and their relationships with the enteric glia in whole-mount preparations and in cryostat sections. NOS-IR neurons, always encircled by glial processes, were located in both plexuses. Many NOS-IR fibers were seen in the circular muscle layer, in the submucosa, and in the mucosa. In the submucosa they were close to the lymphoid tissue. No differences in the distribution and percentage of NOS-IR fibers and neurons were observed among sheep carrying different PrP genotype, thus making unlikely their contribution in the determinism of susceptibility/resistance to scrapie infection.
Collapse
|
34
|
Aguzzi A, Heikenwalder M. Pathogenesis of prion diseases: current status and future outlook. Nat Rev Microbiol 2006; 4:765-75. [PMID: 16980938 DOI: 10.1038/nrmicro1492] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The prion, a conformational variant of a host protein, is the infectious particle responsible for transmissible spongiform encephalopathy (TSE), a fatal neurodegenerative disease of humans and animals. The principal target of prion pathology is the brain, yet most TSEs also display prion replication at extra-cerebral locations, including secondary lymphoid organs and sites of chronic inflammation. Despite significant progress in our understanding of this infectious agent, many fundamental questions relating to the nature of the prion, including the mechanism of replication and the molecular events underlying brain damage, remain unanswered. Here we focus on the unresolved issues pertaining to prion pathogenesis, particularly on the role played by the immune system.
Collapse
Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zürich, Schmelzbergstrasse 12, CH-8091 Zürich, Switzerland.
| | | |
Collapse
|