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Abstract
The cellular prion protein (PrPC) has been widely investigated ever since its conformational isoform, the prion (or PrPSc), was identified as the etiological agent of prion disorders. The high homology shared by the PrPC-encoding gene among mammals, its high turnover rate and expression in every tissue strongly suggest that PrPC may possess key physiological functions. Therefore, defining PrPC roles, properties and fate in the physiology of mammalian cells would be fundamental to understand its pathological involvement in prion diseases. Since the incidence of these neurodegenerative disorders is enhanced in aging, understanding PrPC functions in this life phase may be of crucial importance. Indeed, a large body of evidence suggests that PrPC plays a neuroprotective and antioxidant role. Moreover, it has been suggested that PrPC is involved in Alzheimer disease, another neurodegenerative pathology that develops predominantly in the aging population. In prion diseases, PrPC function is likely lost upon protein aggregation occurring in the course of the disease. Additionally, the aging process may alter PrPC biochemical properties, thus influencing its propensity to convert into PrPSc. Both phenomena may contribute to the disease development and progression. In Alzheimer disease, PrPC has a controversial role because its presence seems to mediate β-amyloid toxicity, while its down-regulation correlates with neuronal death. The role of PrPC in aging has been investigated from different perspectives, often leading to contrasting results. The putative protein functions in aging have been studied in relation to memory, behavior and myelin maintenance. In aging mice, PrPC changes in subcellular localization and post-translational modifications have been explored in an attempt to relate them to different protein roles and propensity to convert into PrPSc. Here we provide an overview of the most relevant studies attempting to delineate PrPC functions and fate in aging.
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Affiliation(s)
- Lisa Gasperini
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati Trieste, Italy
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati Trieste, Italy
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2
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Santo KP, Berjanskii M, Wishart DS, Stepanova M. Comparative analysis of essential collective dynamics and NMR-derived flexibility profiles in evolutionarily diverse prion proteins. Prion 2011; 5:188-200. [PMID: 21869604 DOI: 10.4161/pri.5.3.16097] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Collective motions on ns-μs time scales are known to have a major impact on protein folding, stability, binding and enzymatic efficiency. It is also believed that these motions may have an important role in the early stages of prion protein misfolding and prion disease. In an effort to accurately characterize these motions and their potential influence on the misfolding and prion disease transmissibility we have conducted a combined analysis of molecular dynamic simulations and NMR-derived flexibility measurements over a diverse range of prion proteins. Using a recently developed numerical formalism, we have analyzed the essential collective dynamics (ECD) for prion proteins from 8 different species including human, cow, elk, cat, hamster, chicken, turtle and frog. We also compared the numerical results with flexibility profiles generated by the random coil index (RCI) from NMR chemical shifts. Prion protein backbone flexibility derived from experimental NMR data and from theoretical computations show strong agreement with each other, demonstrating that it is possible to predict the observed RCI profiles employing the numerical ECD formalism. Interestingly, flexibility differences in the loop between second beta strand (S2) and the second alpha helix (HB) appear to distinguish prion proteins from species that are susceptible to prion disease and those that are resistant. Our results show that the different levels of flexibility in the S2-HB loop in various species are predictable via the ECD method, indicating that ECD may be used to identify disease resistant variants of prion proteins, as well as the influence of prion proteins mutations on disease susceptibility or misfolding propensity.
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3
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Gene expression profiling and association with prion-related lesions in the medulla oblongata of symptomatic natural scrapie animals. PLoS One 2011; 6:e19909. [PMID: 21629698 PMCID: PMC3101219 DOI: 10.1371/journal.pone.0019909] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 04/06/2011] [Indexed: 02/04/2023] Open
Abstract
The pathogenesis of natural scrapie and other prion diseases remains unclear. Examining transcriptome variations in infected versus control animals may highlight new genes potentially involved in some of the molecular mechanisms of prion-induced pathology. The aim of this work was to identify disease-associated alterations in the gene expression profiles of the caudal medulla oblongata (MO) in sheep presenting the symptomatic phase of natural scrapie. The gene expression patterns in the MO from 7 sheep that had been naturally infected with scrapie were compared with 6 controls using a Central Veterinary Institute (CVI) custom designed 4×44K microarray. The microarray consisted of a probe set on the previously sequenced ovine tissue library by CVI and was supplemented with all of the Ovis aries transcripts that are currently publicly available. Over 350 probe sets displayed greater than 2-fold changes in expression. We identified 148 genes from these probes, many of which encode proteins that are involved in the immune response, ion transport, cell adhesion, and transcription. Our results confirm previously published gene expression changes that were observed in murine models with induced scrapie. Moreover, we have identified new genes that exhibit differential expression in scrapie and could be involved in prion neuropathology. Finally, we have investigated the relationship between gene expression profiles and the appearance of the main scrapie-related lesions, including prion protein deposition, gliosis and spongiosis. In this context, the potential impacts of these gene expression changes in the MO on scrapie development are discussed.
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Fish models in prion biology: underwater issues. Biochim Biophys Acta Mol Basis Dis 2010; 1812:402-14. [PMID: 20933080 DOI: 10.1016/j.bbadis.2010.09.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2009] [Revised: 09/11/2010] [Accepted: 09/21/2010] [Indexed: 12/14/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs), otherwise known as prion disorders, are fatal diseases causing neurodegeneration in a wide range of mammalian hosts, including humans. The causative agents - prions - are thought to be composed of a rogue isoform of the endogenous prion protein (PrP). Beyond these and other basic concepts, fundamental questions in prion biology remain unanswered, such as the physiological function of PrP, the molecular mechanisms underlying prion pathogenesis, and the origin of prions. To date, the occurrence of TSEs in lower vertebrates like fish and birds has received only limited attention, despite the fact that these animals possess bona fide PrPs. Recent findings, however, have brought fish before the footlights of prion research. Fish models are beginning to provide useful insights into the roles of PrP in health and disease, as well as the potential risk of prion transmission between fish and mammals. Although still in its infancy, the use of fish models in TSE research could significantly improve our basic understanding of prion diseases, and also help anticipate risks to public health. This article is part of a Special Issue entitled Zebrafish Models of Neurological Diseases.
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Saunders GC, Cawthraw S, Mountjoy SJ, Tout AC, Sayers AR, Hope J, Windl O. Ovine PRNP untranslated region and promoter haplotype diversity. J Gen Virol 2009; 90:1289-1293. [DOI: 10.1099/vir.0.007997-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The diversity and possible contribution of non-coding regions of the prion protein (PrP) gene (PRNP) to transmissible spongiform encephalopathy susceptibility and PrP regulation are not fully known. This study defined ten ovine PRNP promoters and five untranslated region (UTR) haplotypes found in atypical and classical scrapie cases and healthy control sheep. A greater diversity of promoter and UTR haplotypes was observed in conjunction with the ARQ PrP allele (seven promoter and four UTR haplotypes), while it was observed that the other alleles were linked with a limited number of haplotypes, such as ARR, found to be linked to only two promoter and one UTR haplotypes. In silico analysis identified potential transcription factor binding sites that differed in the promoter haplotype variants. Furthermore, a 5′ UTR internal ribosome entry site motif was identified in exon 2 and highlights a possible role for this exon in regulating PrP expression at the translational level.
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Affiliation(s)
- Ginny C. Saunders
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Saira Cawthraw
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Susan J. Mountjoy
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Anna C. Tout
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Anthony R. Sayers
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Jim Hope
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
| | - Otto Windl
- Department of Molecular Pathogenesis and Genetics, Veterinary Laboratories Agency, New Haw, Addlestone, Surrey KT15 3NB, UK
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Gossner AG, Bennet N, Hunter N, Hopkins J. Differential expression of Prnp and Sprn in scrapie infected sheep also reveals Prnp genotype specific differences. Biochem Biophys Res Commun 2008; 378:862-6. [PMID: 19070601 DOI: 10.1016/j.bbrc.2008.12.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Accepted: 12/02/2008] [Indexed: 01/25/2023]
Abstract
The central role for PrP in the pathogenesis of the transmissible spongiform encephalopathies (TSEs) is illustrated by the resistance of Prnp(0/0) mice to disease and by the inverse association of Prnp gene dosage with incubation period. Understanding the role of PrP(C) in TSEs necessitates knowledge of expression levels of the Prnp gene during the development of disease. SSBP/1 scrapie shows a defined pattern of disease progression and here we show that Prnp and shadow of PrP (Sprn) are differentially expressed in different brain areas and lymphoid tissues. Counter-intuitively we found that there is no positive correlation between expression of Prnp or Sprn and patterns of disease progression. Prnp and Sprn expression levels are both influenced by Prnp genotype; although the scrapie-sensitive VRQ/VRQ sheep did not express the highest level of either. In addition, infection with SSBP/1 scrapie seems to have little effect on either PrP or Shadoo expression levels.
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Affiliation(s)
- A G Gossner
- Division of Infection & Immunity, The Roslin Institute, Royal Dick School of Veterinary Studies, University of Edinburgh, Summerhall, Edinburgh, UK
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7
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Complete genomic sequence of the goat prion protein gene (PRNP). Virus Genes 2008; 38:189-92. [DOI: 10.1007/s11262-008-0288-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2008] [Accepted: 09/10/2008] [Indexed: 11/26/2022]
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Linden R, Martins VR, Prado MAM, Cammarota M, Izquierdo I, Brentani RR. Physiology of the prion protein. Physiol Rev 2008; 88:673-728. [PMID: 18391177 DOI: 10.1152/physrev.00007.2007] [Citation(s) in RCA: 435] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Prion diseases are transmissible spongiform encephalopathies (TSEs), attributed to conformational conversion of the cellular prion protein (PrP(C)) into an abnormal conformer that accumulates in the brain. Understanding the pathogenesis of TSEs requires the identification of functional properties of PrP(C). Here we examine the physiological functions of PrP(C) at the systemic, cellular, and molecular level. Current data show that both the expression and the engagement of PrP(C) with a variety of ligands modulate the following: 1) functions of the nervous and immune systems, including memory and inflammatory reactions; 2) cell proliferation, differentiation, and sensitivity to programmed cell death both in the nervous and immune systems, as well as in various cell lines; 3) the activity of numerous signal transduction pathways, including cAMP/protein kinase A, mitogen-activated protein kinase, phosphatidylinositol 3-kinase/Akt pathways, as well as soluble non-receptor tyrosine kinases; and 4) trafficking of PrP(C) both laterally among distinct plasma membrane domains, and along endocytic pathways, on top of continuous, rapid recycling. A unified view of these functional properties indicates that the prion protein is a dynamic cell surface platform for the assembly of signaling modules, based on which selective interactions with many ligands and transmembrane signaling pathways translate into wide-range consequences upon both physiology and behavior.
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Affiliation(s)
- Rafael Linden
- Instituto de Biofísica da Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
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Kikuchi Y, Kakeya T, Nakajima O, Sakai A, Ikeda K, Yamaguchi N, Yamazaki T, Tanamoto KI, Matsuda H, Sawada JI, Takatori K. Hypoxia induces expression of a GPI-anchorless splice variant of the prion protein. FEBS J 2008; 275:2965-76. [PMID: 18445040 DOI: 10.1111/j.1742-4658.2008.06452.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The human prion protein (PrP) is a glycoprotein with a glycosylphosphatidylinositol (GPI) anchor at its C-terminus. Here we report alternative splicing within exon 2 of the PrP gene (PRNP) in the human glioblastoma cell line T98G. The open reading frame of the alternatively spliced mRNA lacked the GPI anchor signal sequence and encoded a 230 amino acid polypeptide. Its product, GPI-anchorless PrP (GPI(-) PrPSV), was unglycosylated and soluble in non-ionic detergent, and was found in the cytosolic fraction. We also detected low levels of alternatively spliced mRNA in human brain and non-neuronal tissues. When long-term passaged T98G cells were placed in a low-oxygen environment, alternatively spliced mRNA expression increased and expression of normally spliced PrP mRNA decreased. These findings imply that oxygen tension regulates GPI(-) PrPSV expression in T98G cells.
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Affiliation(s)
- Yutaka Kikuchi
- Division of Microbiology, National Institute of Health Sciences, Tokyo, Japan.
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10
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Goldmann W. PrP genetics in ruminant transmissible spongiform encephalopathies. Vet Res 2008; 39:30. [PMID: 18284908 DOI: 10.1051/vetres:2008010] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2007] [Accepted: 01/24/2008] [Indexed: 11/15/2022] Open
Abstract
Scrapie, bovine spongiform encephalopathy (BSE), and chronic wasting disease (CWD) are prion diseases in ruminants with considerable impact on animal health and welfare. They can also pose a risk to human health and control is therefore an important issue. Prion protein (PrP) genetics may be used to control and eventually eradicate animal prion diseases. The PrP gene in sheep and other representatives of the order Artiodactyles has many polymorphisms of which several are crucial determinants of susceptibility to prion diseases, also known as transmissible spongiform encephalopathies (TSE). This review will present the current understanding of PrP genetics in ruminants highlighting similarity and difference between the species in the context of TSE.
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Affiliation(s)
- Wilfred Goldmann
- Roslin Institute Neuropathogenesis Unit, West Mains Road, Edinburgh EH 93JF, UK.
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11
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Sweeney T, Hanrahan JP. The evidence of associations between prion protein genotype and production, reproduction, and health traits in sheep. Vet Res 2008; 39:28. [DOI: 10.1051/vetres:2008004] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Accepted: 01/15/2007] [Indexed: 11/14/2022] Open
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12
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Abstract
Transmissible spongiform encephalopathies (TSEs) are infectious, fatal neurodegenerative diseases characterized by aggregates of modified forms of the prion protein (PrP) in the central nervous system. Well known examples include variant Creutzfeldt-Jakob Disease (vCJD) in humans, BSE in cattle, chronic wasting disease in deer and scrapie in sheep and goats. In humans, sheep and deer, disease susceptibility is determined by host genotype at the prion protein gene (PRNP). Here I examine the molecular evolution of PRNP in ruminants and show that variation in sheep appears to have been maintained by balancing selection, a profoundly different process from that seen in other ruminants. Scrapie eradication programs such as those recently implemented in the UK, USA and elsewhere are based on the assumption that PRNP is under positive selection in response to scrapie. If, as these data suggest, that assumption is wrong, eradication programs will disrupt this balancing selection, and may have a negative impact on the fitness or scrapie resistance of national flocks.
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Affiliation(s)
- Jon Slate
- University of Sheffield, Department of Animal and Plant Sciences, Sheffield, S10 2TN, UK.
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O'Neill GT, Cairns D, Toovey L, Goldmann W, Hunter N. New ovine PrP gene haplotypes as a result of single nucleotide polymorphisms in the PrP gene promoter. J Anim Breed Genet 2005; 122:86-94. [PMID: 16130475 DOI: 10.1111/j.1439-0388.2005.00520.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Incidence of scrapie in sheep is strongly associated with PrP gene amino acid codon variants at positions 136, 154 and 171. However, there are breed differences in disease linkage and anomalous disease patterns which cannot obviously be explained by the '3 codon' genotype. Mouse studies indicate that PrP protein levels can influence scrapie disease progression and this prompted us to study the sheep PrP gene promoter region in a search for novel polymorphisms which may influence gene expression and hence disease susceptibility. The incidence of three single nucleotide polymorphisms (SNP) at positions C/A-5354, T/C-5382 and C/G-5622 within the PrP gene promoter region was determined from Neuropathogenesis Unit (NPU) and New Zealand (NZ) Cheviot and UK and NZ Suffolk sheep. The SNP variants A-5354 and G-5622 created consensus sequences for STAT and SP1 transcription factors, respectively, and C-5382 was within Motif 1, one of four conserved motifs found within the promoter region of mammalian PrP genes. The occurrence of C/A-5354 and T/C-5384 SNP exhibited differential associations with the PrP open reading frame (ORF) variants linked to scrapie susceptibility. A significant imbalance in the incidence of the C-5354/AXQ haplotype was found in the NPU Cheviot flock. C-5382 was not found in Suffolk sheep of either UK or NZ origin. The G-5622 SNP was found at a lower incidence in Suffolk sheep compared with Cheviots. The range of transcription factor binding motif profiles in the PrP gene promoter may act to modulate PrP gene activity and warrants further large-scale study.
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Affiliation(s)
- G T O'Neill
- Institute for Animal Health, Neuropathogenesis Unit, Edinburgh, UK.
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Maddison BC, Patel S, James RF, Conlon HE, Oidtmann B, Baier M, Whitelam GC, Gough KC. Generation and characterisation of monoclonal antibodies to Rainbow trout (Oncorhynchus mykiss) prion protein. J Immunol Methods 2005; 306:202-10. [PMID: 16225888 DOI: 10.1016/j.jim.2005.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Revised: 07/26/2005] [Accepted: 09/07/2005] [Indexed: 11/24/2022]
Abstract
We report the production and characterisation of three monoclonal antibodies to the prion protein (PrP) of Rainbow trout (Oncorhynchus mykiss), a piscine protein with characteristic structural features common to mammalian prion protein. All of the antibodies were used to detect PrP in ELISA, Western blot and by immunohistochemistry. The antibodies showed specificity for certain genera of the Salmonidae, binding to PrP of Rainbow trout and Atlantic salmon (Salmo salar) but not to that from Arctic char (Salvelinus alpinus). Using the immunoreagents in Western blots, we demonstrated that O. mykiss PrP protein is a 64 kDa protein present in brain, spinal chord and optic nerve. PrP was not detected in a range of peripheral tissues: eye, heart, stomach, intestine, liver, kidney, spleen, muscle and skin. Furthermore, PrP could be detected in all brain regions studied: optic lobe, cerebrum/olfactory lobe, cerebellum, hypothalamus/pituitary and medulla oblongata and was widespread within these tissues as determined by immunohistochemistry. These immunoreagents provide specific tools to study the biology of Rainbow trout and Atlantic salmon PrP and any possible transmissible spongiform encephalopathy-like disease of these economically important fish species.
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Affiliation(s)
- B C Maddison
- ADAS, Animal Health and Welfare, Biotechnology Group, Department of Biology, University of Leicester, Adrian Building, University Road, Leicester, LE1 7RH, Leicestershire, UK
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Garcia-Crespo D, Juste RA, Hurtado A. Selection of ovine housekeeping genes for normalisation by real-time RT-PCR; analysis of PrP gene expression and genetic susceptibility to scrapie. BMC Vet Res 2005; 1:3. [PMID: 16188044 PMCID: PMC1262732 DOI: 10.1186/1746-6148-1-3] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2005] [Accepted: 09/28/2005] [Indexed: 11/23/2022] Open
Abstract
Background Cellular prion protein expression is essential for the development of transmissible spongiform encephalopathies (TSEs), and in sheep, genetic susceptibility to scrapie has been associated to PrP gene polymorphisms. To test the hypothetical linkage between PrP gene expression and genetic susceptibility, PrP mRNA levels were measured by real-time RT-PCR in six ovine tissues of animals with different genotypes. Results Previous to the PrP gene expression analysis the stability of several housekeeping (HK) genes was assessed in order to select the best ones for relative quantification. The normalisation of gene expression was carried out using a minimum of three HK genes in order to detect small expression differences more accurately than using a single control gene. The expression stability analysis of six HK genes showed a large tissue-associated variation reflecting the existence of tissue-specific factors. Thereby, a specific set of HK genes was required for an accurate normalisation of the PrP gene expression within each tissue. Statistical differences in the normalised PrP mRNA levels were found among the tissues, obtaining the highest expression level in obex, followed by ileum, lymph node, spleen, cerebellum and cerebrum. A tendency towards increased PrP mRNA levels and genetic susceptibility was observed in central nervous system. However, the results did not support the hypothesis that PrP mRNA levels vary between genotypes. Conclusion The results on PrP gene expression presented here provide valuable baseline data for future studies on scrapie pathogenesis. On the other hand, the results on stability data of several HK genes reported in this study could prove very useful in other gene expression studies carried out in these relevant ovine tissues.
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Affiliation(s)
- David Garcia-Crespo
- Department of Animal Health, Instituto Vasco de Investigación y Desarrollo Agrario (NEIKER); Berreaga, 1. 48160 Derio, Bizkaia, Spain
| | - Ramón A Juste
- Department of Animal Health, Instituto Vasco de Investigación y Desarrollo Agrario (NEIKER); Berreaga, 1. 48160 Derio, Bizkaia, Spain
| | - Ana Hurtado
- Department of Animal Health, Instituto Vasco de Investigación y Desarrollo Agrario (NEIKER); Berreaga, 1. 48160 Derio, Bizkaia, Spain
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González L, Terry L, Jeffrey M. Expression of Prion Protein in the Gut of Mice Infected Orally with the 301V Murine Strain of the Bovine Spongiform Encephalopathy Agent. J Comp Pathol 2005; 132:273-82. [PMID: 15893985 DOI: 10.1016/j.jcpa.2004.10.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Accepted: 10/31/2004] [Indexed: 11/20/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs) are characterized by the accumulation of an abnormal, disease-associated prion protein (PrP(d)). Expression of its normal cellular counterpart (PrP(c)) by the host is a pre-requisite for the spread of infection to the central nervous system and the development of disease. Moreover, cells expressing PrP(c) at specific sites such as the gastrointestinal tract might be regarded as the initial point of PrP(c)-PrP(d) conversion after infection by the oral route. In this study, inbred mice of the I/M strain were infected orally with the 301V murine strain of the bovine spongiform encephalopathy agent. The expression of PrP(c) and the accumulation of PrP(d) in the intestine was then investigated immunohistochemically, together with the variations in immunoreactivity that resulted from different pretreatments of the tissue. After proteinase K (PK) pretreatment, abnormal PrP was still detectable only in the gut-associated lymphoid tissue (GALT) of clinically affected mice and, to a much more limited degree, in the enteric nervous system (ENS). Cellular PrP that disappeared after PK treatment was particularly conspicuous in the ENS and present to a lesser extent in the GALT of all mice examined after inoculation with 301V or with normal brain homogenates, as well as in uninoculated controls. These findings suggested that not all PrP found in infected mice was PrP(d) and that part of the PrP(d) was sensitive to PK treatment. Reactivity to PrP antibody 1A8 was consistently found in the absorptive epithelium of the intestinal villi, with or without PK pretreatment. However, epithelial immunolabelling was comparable in inoculated and uninoculated mice and was also consistently seen in PrP "knockout" mice used as controls. It is therefore concluded that immunohistochemically detectable accumulation of PrP(d) in the gut of mice is a relatively late event in the pathogenesis of experimental infection in this model and that the immunoreactivity observed in the intestinal epithelium does not correspond to PrP expression. While enterocytes may still play a role in the uptake of infection from the intestinal lumen, the results do not suggest that these cells are a site of initial accumulation of PrP(d).
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Affiliation(s)
- L González
- Veterinary Laboratories Agency (VLA-Lasswade), Pentlands Science Park, Midlothian EH26 0PZ, UK
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17
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Somerville RA, Hamilton S, Fernie K. Transmissible spongiform encephalopathy strain, PrP genotype and brain region all affect the degree of glycosylation of PrPSc. J Gen Virol 2005; 86:241-246. [PMID: 15604453 DOI: 10.1099/vir.0.80251-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Transmissible spongiform encephalopathies (TSEs), sometimes known as prion diseases, are caused by an infectious agent whose molecular properties have not been determined. Traditionally, different strains of TSE diseases are characterized by a series of phenotypic properties after passage in experimental animals. More recently it has been recognized that diversity in the degree to which an abnormal form of the host protein PrP, denoted PrPSc, is glycosylated and the migration of aglycosyl forms of PrPSc on immunoblots may have some differential diagnostic potential. It has been recognized that these factors are affected by the strain of TSE agent but also by other factors, e.g. location within the brain. This study shows in some cases, but not others, that host PrP genotype has a major influence on the degree of PrPSc glycosylation and migration on gels and provides further evidence of the effect of brain location. Accordingly both the degree of glycosylation and the apparent molecular mass of PrPSc may be of some value for differential diagnosis between TSE strains, but only when host effects are taken into account. Furthermore, the data inform the debate about how these differences arise, and favour hypotheses proposing that TSE agents affect glycosylation of PrP during its biosynthesis.
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Affiliation(s)
- Robert A Somerville
- Neuropathogenesis Unit, Institute for Animal Health, West Mains Road, Edinburgh EH9 3JF, UK
| | - Scott Hamilton
- Neuropathogenesis Unit, Institute for Animal Health, West Mains Road, Edinburgh EH9 3JF, UK
| | - Karen Fernie
- Neuropathogenesis Unit, Institute for Animal Health, West Mains Road, Edinburgh EH9 3JF, UK
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Sander P, Hamann H, Pfeiffer I, Wemheuer W, Brenig B, Groschup MH, Ziegler U, Distl O, Leeb T. Analysis of sequence variability of the bovine prion protein gene (PRNP) in German cattle breeds. Neurogenetics 2004; 5:19-25. [PMID: 14727152 DOI: 10.1007/s10048-003-0171-y] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2003] [Accepted: 11/27/2003] [Indexed: 11/25/2022]
Abstract
Different alleles of the prion protein gene (PRNP) of human and sheep are known to be associated with varying susceptibilities to transmissible spongiform encephalopathies. However, no polymorphisms in the bovine PRNP gene with an effect on susceptibility to prion diseases have been identified to date. In this study we investigated such polymorphisms in German cattle; 48 healthy animals from six different German cattle breeds and 43 cattle with bovine spongiform encephalopathy (BSE) were analyzed. In contrast to previous studies, all three exons as well as the promoter region of the PRNP gene were investigated. Sequence variants in the bovine PRNP gene could have an impact on the amino acid sequence or the expression level of the prion protein and thus on susceptibility to BSE. We identified a total of 60 polymorphisms in the PRNP gene of German cattle. Of these 60 polymorphisms, 36 were newly identified, whereas 24 of these polymorphisms had been described previously. We did not detect any novel polymorphisms affecting the amino acid sequence of the prion protein. However, we identified a 23-bp insertion/deletion polymorphism in the putative PRNP promoter region that shows a significant association with BSE susceptibility in our animals.
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Affiliation(s)
- Petra Sander
- Institute of Animal Breeding and Genetics, School of Veterinary Medicine Hannover, Bünteweg 17 p, 30559 Hannover, Germany
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19
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Koster T, Singh K, Zimmermann M, Gruys E. Emerging therapeutic agents for transmissible spongiform encephalopathies: a review. J Vet Pharmacol Ther 2004; 26:315-26. [PMID: 14633183 DOI: 10.1046/j.1365-2885.2003.00525.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Transmissible spongiform encephalopathies (TSEs) are a group of fatal neurodegenerative disorders associated with misfolding of prion protein, from PrPC to PrPSc. Different types of experimental studies have resulted in a better understanding of the pathogenesis of the prion diseases. Genetic and molecular properties of PrP isoforms have been explained but the conformational conversion of the PrPC isoform to the PrPSc isoform has not yet been entirely elucidated. However, a number of possible therapeutic agents have been tried and some have proven to be effective against TSEs but most have limitations in terms of toxicity and pharmacokinetics. Congo red (CR), anthracyclines, and polyanionic dextran sulfate have limited ability to cross the blood-brain barrier and may be toxic. The efficacy of polyene antibiotics seems to be restricted to certain scrapie strains. Tetrapyrroles and tetracyclines with low toxicities and favorable pharmacokinetics could be useful in preventing PrPSc accumulation. Compounds like branched polyamines, Cp-60, analogs of CR, quinacrine and chlorpromazine, beta-sheet breaker peptides and inhibitory peptides, active immunization using recombinant PrP and passive immunization with anti-PrP antibodies, have potential use as therapeutic agents but would need further research and clinical trials.
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Affiliation(s)
- T Koster
- Department of Pathology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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20
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Fujisawa M, Kanai Y, Nam SY, Maeda S, Nakamuta N, Kano K, Kurohmaru M, Hayashi Y. Expression of Prnp mRNA (Prion Protein Gene) in Mouse Spermatogenic Cells. J Reprod Dev 2004; 50:565-70. [PMID: 15514463 DOI: 10.1262/jrd.50.565] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Prnp (prion protein) gene, which encodes a soluble protein anchored to the cell surface by glycosylphosphatidylinositol (GPI), might be involved in cell-to-cell interaction. The expression of Prnp is strongly observed not only in the brain, but also in non-neuronal tissues. In order to examine the Prnp expression sites in mouse testes, we carried out Northern blot and in situ hybridization analyses. By Northern blot analysis, two kinds of Prnp transcripts (major band of 2.2 kb, and minor band of 1.1 kb) were detected in testes. The 2.2-kb transcript was observed in testes throughout the postnatal development, whereas the 1.1-kb transcript was observed in testes from 2 to 70 weeks old. In situ hybridization analysis showed that the positive signals for Prnp mRNAs were predominantly observed in spermatogenic cells, but not in somatic cells such as Sertoli cells, Leydig cells and peritubular myoid cells. The signals were observed moderately in spermatogonia, and strongly in spermatocytes and round spermatids, but not in elongate spermatids and spermatozoa. These results suggest that Prnp may be involved in germ cell differentiation during mammalian spermatogenesis.
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Affiliation(s)
- Masahiko Fujisawa
- Department of Veterinary Anatomy, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Yayoi, Bunkyo-ku, Japan.
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Hills D, Schlaepfer J, Comincini S, MacLean I, Dolf G, Ferretti L, Olsaker I, Williams JL. Sequence variation in the bovine and ovine PRNP genes. Anim Genet 2003; 34:183-90. [PMID: 12755818 DOI: 10.1046/j.1365-2052.2003.00977.x] [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: 11/20/2022]
Abstract
A resequencing approach was adopted to identify sequence variants in the PRNP gene that may affect susceptibility or resistance to bovine spongiform encephalopathy. The entire PRNP gene (>21 kb) was sequenced from 26 chromosomes from a group of Holstein-Friesian cows, as well as exon 3 of PRNP (>4 kb) from a further 24 chromosomes from six diverse breeds. We identified 51 variant sequences of which 42 were single nucleotide polymorphisms and nine were insertion/deletion (indel) events. The study was extended to exon 3 of the sheep PRNP gene where 23 sequence variants were observed, four of which were indels. The level of nucleotide diversity in the complete bovine PRNP gene was pi = 0.00079, which is similar to that found at the bovine T-cell receptor alpha delta joining region (pi = 0.00077), but somewhat less than that observed for the bovine leptin (pi = 0.00265). Sequence variation within exon 3 of PRNP in both cattle (pi = 0.00102) and sheep (pi = 0.00171) was greater than that for the complete PRNP gene, with sheep showing greater sequence variation in exon 3 than cattle. The level of sequence variation reported here is greater than previously thought for the bovine PRNP gene in cattle. This study highlights the contribution that recombination plays in increasing allelic diversity in this species.
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Affiliation(s)
- D Hills
- Roslin Institute (Edinburgh), Roslin, Midlothian, Scotland, UK.
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22
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O'Neill GT, Donnelly K, Marshall E, Cairns D, Goldmann W, Hunter N. Characterization of ovine PrP gene promoter activity in N2a neuroblastoma and ovine foetal brain cell lines. J Anim Breed Genet 2003. [DOI: 10.1046/j.1439-0388.2003.00381.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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23
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Barclay GR, Houston EF, Halliday SI, Farquhar CF, Turner ML. Comparative analysis of normal prion protein expression on human, rodent, and ruminant blood cells by using a panel of prion antibodies. Transfusion 2002; 42:517-26. [PMID: 12084159 DOI: 10.1046/j.1537-2995.2002.00095.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND It is not known whether variant CJD can be transmitted within the human population by blood transfusion. The expression of normal cellular prion protein (PrPC) by different blood cell types may permit selective uptake and dissemination of infectivity. STUDY DESIGN AND METHODS The normal distribution of PrPC on the major blood cell types of species known to be susceptible to natural or experimental transmissible spongiform encephalopathies was studied. Blood from healthy humans, mice, hamsters, cattle, and sheep was examined by flow cytometry by using a large panel of antibodies with different prion protein (PrP) epitope specificities to maximize the detection of PrP variants across species and cell type. RESULTS PrP was detected on all major human blood cells types except eosinophils, but was not detected as ubiquitously or uniformly on major blood cell types of different animal species. CONCLUSION Different animal species have unique patterns of expression of PrPC on blood cell types, with none equivalent to the human pattern. This needs to be considered when extrapolating from animal models of blood-borne transmissible spongiform encephalopathy infectivity, particularly in regard to the risk assessment of potential variant CJD spread within the human population. The relationship between PrP distribution and infectivity distribution in blood needs further investigation.
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Affiliation(s)
- G Robin Barclay
- Scottish National Blood Transfusion Service Cell Therapy Group, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom.
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24
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Rybner C, Hillion J, Sahraoui T, Lanotte M, Botti J. All-trans retinoic acid down-regulates prion protein expression independently of granulocyte maturation. Leukemia 2002; 16:940-8. [PMID: 11986958 DOI: 10.1038/sj.leu.2402443] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2001] [Accepted: 12/17/2001] [Indexed: 11/09/2022]
Abstract
The cellular prion protein (PrPc) is a sialoglycoprotein involved in the pathogenesis of prion diseases. It has been identified at the plasma membrane of several cell types. All-trans retinoic acid (ATRA) is known to induce differentiation of human leukemia cell lines in vitro. PrPc messenger ribonucleic acid (mRNA) and protein are down-regulated upon ATRA-induced differentiation of HL60 cells. In this report, we have investigated the regulation of PrPc mRNA and protein expression during ATRA-treatment of maturation-sensitive (NB4) and -resistant (NB4-R1 and NB4-R2) cell lines. In ATRA-induced maturation of NB4 cells, down-regulation of PrPc mRNA and protein were observed. We also show that down-regulation of PrPc mRNA is dependent on protein synthesis. Moreover, the same down-regulation of prion protein by ATRA was observed at the surface of maturation-resistant, ATRA-responsive NB4-R1 cells. In contrast, the maturation-resistant and ATRA-unresponsive NB4-R2 subline showed no variation in membrane prion protein expression. These results demonstrate a dissociation between the regulation of prion protein expression by ATRA and the process of granulocyte maturation. We propose that retinoids should be investigated further as a preventive strategy to slow down prion disease progression.
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Affiliation(s)
- C Rybner
- INSERM U-496, Institut Universitaire d'Hématologie (IUH), Hôpital Saint-Louis, Paris, France
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25
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Humeny A, Schiebel K, Seeber S, Becker CM. Identification of polymorphisms within the bovine prion protein gene (Prnp) by DNA sequencing and genotyping by MALDI-TOF-MS. Neurogenetics 2002; 4:59-60. [PMID: 12030333 DOI: 10.1007/s10048-001-0126-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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26
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Abstract
Natural scrapie in sheep occurs through a complex interplay between host genetic elements and various strains of the infectious scrapie agent. Scrapie-related polymorphisms in the coding region of the prion protein (PrP) gene, Prnp, have been studied in a number of breeds. The disease-promoting V136 allele, and the susceptibility-reducing R171 allele, have proved to be most important. However, variation in the coding region of Prnp cannot alone explain the diverse patterns of scrapie susceptibility in various breeds. For instance, in many breeds plagued with scrapie, the V136 allele appears to be a rarity. The R171 allele greatly reduces scrapie susceptibility This lays the molecular foundation for marker-assisted breeding for reduced scrapie susceptibility now underway in many countries. Although potentially important, and still under investigation, variable expression level and pattern of the ovine Prnp appears to be of little importance for the occurrence of natural scrapie. Studies of scrapie in mice also indicate that genetic elements other than Prnp may have a strong influence on scrapie incubation time, and hence susceptibility. Narrowing down the search to focus on these elements and identification of candidate genes are important tasks for future research in sheep scrapie.
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Affiliation(s)
- Michael A Tranulis
- Department of Biochemistry, Physiology and Nutrition, Norwegian School of Veterinary Science, Oslo.
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27
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Moudjou M, Frobert Y, Grassi J, La Bonnardière C. Cellular prion protein status in sheep: tissue-specific biochemical signatures. J Gen Virol 2001; 82:2017-2024. [PMID: 11458009 DOI: 10.1099/0022-1317-82-8-2017] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Expression of the cellular prion protein PrP(C) is sine qua none for the development of transmissible spongiform encephalopathy and thus for the accumulation of the illness-associated conformer PrP(Sc). Therefore, the tissue distribution of PrP(C) at the protein level in both quantitative and qualitative terms was investigated. PrP(C) was quantified using a two-site enzyme immunometric assay which was calibrated with purified ovine recombinant prion protein (rPrP). The most PrP(C)-rich tissue was the brain, followed by the lungs, skeletal muscle, heart, uterus, thymus and tongue, which contained between 20- and 50-fold less PrP(C) than the brain. The PrP(C) content of these tissues seems to be comparable between sheep. Other organs, however, showed different, but low, levels of the protein depending on the animal examined. This was also the case for tissues from the gastrointestinal tract. The tissue containing the lowest concentration of PrP(C) was shown to be the liver, where PrP(C) was found to be between 564- and 16000-fold less abundant than in the brain. PrP(C) was concentrated from crude cellular extracts by immunoprecipitation using several monoclonal and polyclonal anti-ovine PrP antibodies. Interestingly, it was observed that the isoform profile of PrP(C) was tissue-specific. The most atypical electrophoretic profile of PrP(C) was found in the skeletal muscle, where two polypeptides of 32 and 35 kDa were detected.
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Affiliation(s)
- Mohammed Moudjou
- Institut National de la Recherche Agronomique (INRA) Virologie et Immunologie Moléculaires, 78352 Jouy en Josas, France1
| | - Yveline Frobert
- Unité de Pharmacologie et d'Immunologie, CEA Saclay, Gif/Yvette, France2
| | - Jacques Grassi
- Unité de Pharmacologie et d'Immunologie, CEA Saclay, Gif/Yvette, France2
| | - Claude La Bonnardière
- Institut National de la Recherche Agronomique (INRA) Virologie et Immunologie Moléculaires, 78352 Jouy en Josas, France1
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28
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Vilotte JL, Soulier S, Essalmani R, Stinnakre MG, Vaiman D, Lepourry L, Da Silva JC, Besnard N, Dawson M, Buschmann A, Groschup M, Petit S, Madelaine MF, Rakatobe S, Le Dur A, Vilette D, Laude H. Markedly increased susceptibility to natural sheep scrapie of transgenic mice expressing ovine prp. J Virol 2001; 75:5977-84. [PMID: 11390599 PMCID: PMC114313 DOI: 10.1128/jvi.75.13.5977-5984.2001] [Citation(s) in RCA: 146] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The susceptibility of sheep to scrapie is known to involve, as a major determinant, the nature of the prion protein (PrP) allele, with the VRQ allele conferring the highest susceptibility to the disease. Transgenic mice expressing in their brains three different ovine PrP(VRQ)-encoding transgenes under an endogenous PrP-deficient genetic background were established. Nine transgenic (tgOv) lines were selected and challenged with two scrapie field isolates derived from VRQ-homozygous affected sheep. All inoculated mice developed neurological signs associated with a transmissible spongiform encephalopathy (TSE) disease and accumulated a protease-resistant form of PrP (PrPres) in their brains. The incubation duration appeared to be inversely related to the PrP steady-state level in the brain, irrespective of the transgene construct. The survival time for animals from the line expressing the highest level of PrP was reduced by at least 1 year compared to those of two groups of conventional mice. With one isolate, the duration of incubation was as short as 2 months, which is comparable to that observed for the rodent TSE models with the briefest survival times. No survival time reduction was observed upon subpassaging of either isolate, suggesting no need for adaptation of the agent to its new host. Overexpression of the transgene was found not to be required for transmission to be accelerated compared to that observed with wild-type mice. Conversely, transgenic mice overexpressing murine PrP were found to be less susceptible than tgOv lines expressing ovine PrP at physiological levels. These data argue that ovine PrP(VRQ) provided a better substrate for sheep prion replication than did mouse PrP. Altogether, these tgOv mice could be an improved model for experimental studies on natural sheep scrapie.
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Affiliation(s)
- J L Vilotte
- Génétique Biochimique et Cytogénétique, Institut National de la Recherche Agronomique, 78352 Jouy-en-Josas cedex, France
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29
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Hunter N, Goldmann W, Marshall E, O'Neill G. Sheep and goats: natural and experimental TSEs and factors influencing incidence of disease. ARCHIVES OF VIROLOGY. SUPPLEMENTUM 2001:181-8. [PMID: 11214921 DOI: 10.1007/978-3-7091-6308-5_17] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
The major factor influencing incidence of disease following challenge with transmissible spongiform encephalopathies (TSEs) in sheep is the allotype at amino acid numbers 136, 154 and 171 of the PrP protein. There are at least two groups of TSEs, one which targets the amino acid encoded at position 136 and the other which is more influenced by the amino acid at codon 171. Within these groups of TSE types, there may additionally be sub-types, as resistance to some, but not all, "136-type" TSEs can also be affected by the amino acid at codon 154. In goats, there are also PrP polymorphisms which apparently influence incubation period of TSE disease, however, this has not found to be true for cattle and BSE incidence. Sheep PrP amino acid codons 136, 154 and 171 do not explain everything about, for example, natural scrapie occurrence in sheep flocks, and attention is now turning to the flanking regions of the PrP gene looking for sequence differences in gene expression control motifs which may also have an influence on disease development. The sheep PrP gene produces two mRNAs in peripheral tissues, the result of alternative polyadenylation in the 3' untranslated region of the gene. Results from transfection assays of murine neuroblastoma cells with constructs expressing different regions of ovine PrP mRNA have revealed the presence of sequences in the 3' untranslated region that modulate protein synthesis and have therefore the potential to affect disease progression.
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Affiliation(s)
- N Hunter
- Institute for Animal Health, Neuropathogenesis Unit, Edinburgh, Scotland, UK
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30
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Abstract
The long-term, progressive decay of the central nervous system typifies prion diseases, a group of rare, transmissible maladies affecting humans, sheep, cattle and some other types of mammal. Little is known about the early molecular events in its pathogenesis but the diverse roles of PrP, the prion protein, in its destructive action have recently been re-emphasised.
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Affiliation(s)
- J Hope
- Institute for Animal Health, Berkshire RG20 7NN, Compton, UK.
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31
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Heggebø R, Press CM, Gunnes G, Inge Lie K, Tranulis MA, Ulvund M, Groschup MH, Landsverk T. Distribution of prion protein in the ileal Peyer's patch of scrapie-free lambs and lambs naturally and experimentally exposed to the scrapie agent. J Gen Virol 2000; 81:2327-2337. [PMID: 10950992 DOI: 10.1099/0022-1317-81-9-2327] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A sensitive immunohistochemical procedure was used to investigate the presence of prion protein (PrP) in the ileal Peyer's patch of PrP-genotyped lambs, including scrapie-free lambs and lambs naturally and experimentally exposed to the scrapie agent. The tyramide signal amplification system was used to enhance the sensitivity of conventional immunohistochemical procedures to show that PrP was widely distributed in the enteric nervous plexus supplying the gut wall. In scrapie-free lambs, PrP was also detected in scattered cells in the lamina propria and in the dome and interfollicular areas of the Peyer's patch. In the follicles, staining for PrP was mainly confined to the capsule and cells associated with vascular structures in the light central zone. In lambs naturally exposed to the scrapie agent, staining was prominent in the dome and neck region of the follicles and was also found to be associated with the follicle-associated epithelium. Similar observations were made in lambs that had received a single oral dose of scrapie-infected brain material from sheep with a homologous and heterologous PrP genotype 1 and 5 weeks previously. These studies show that the ileal Peyer's patch in young sheep may be an important site of uptake of the scrapie agent and that the biology of this major gut-associated lymphoid tissue may influence the susceptibility to oral infection in sheep. Furthermore, these studies suggest that homology or heterology between PrP genotypes or the presence of PrP genotypes seldom associated with disease does not impede uptake of PrP.
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Affiliation(s)
- Ragna Heggebø
- Department of Morphology, Genetics and Aquatic Biology1 and Department of Biochemistry, Physiology and Nutrition2, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033, Oslo, Norway
| | - Charles McL Press
- Department of Morphology, Genetics and Aquatic Biology1 and Department of Biochemistry, Physiology and Nutrition2, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033, Oslo, Norway
| | - Gjermund Gunnes
- Department of Morphology, Genetics and Aquatic Biology1 and Department of Biochemistry, Physiology and Nutrition2, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033, Oslo, Norway
| | - Kai Inge Lie
- Department of Morphology, Genetics and Aquatic Biology1 and Department of Biochemistry, Physiology and Nutrition2, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033, Oslo, Norway
| | - Michael A Tranulis
- Department of Morphology, Genetics and Aquatic Biology1 and Department of Biochemistry, Physiology and Nutrition2, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033, Oslo, Norway
| | - Martha Ulvund
- Department of Sheep and Goat Research, Norwegian School of Veterinary Science, Kyrkjevegen 332/334, 4300 Sandnes, Norway3
| | - Martin H Groschup
- Federal Research Centre for Virus Diseases of Animals, Paul-Ehrlich-Str. 28, 72076 Tübingen, Germany4
| | - Thor Landsverk
- Department of Morphology, Genetics and Aquatic Biology1 and Department of Biochemistry, Physiology and Nutrition2, Norwegian School of Veterinary Science, PO Box 8146 Dep., N-0033, Oslo, Norway
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