1
|
Béringue V, Tixador P, Andréoletti O, Reine F, Castille J, Laï TL, Le Dur A, Laisné A, Herzog L, Passet B, Rezaei H, Vilotte JL, Laude H. Host prion protein expression levels impact prion tropism for the spleen. PLoS Pathog 2020; 16:e1008283. [PMID: 32702070 PMCID: PMC7402522 DOI: 10.1371/journal.ppat.1008283] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 08/04/2020] [Accepted: 06/22/2020] [Indexed: 11/18/2022] Open
Abstract
Prions are pathogens formed from abnormal conformers (PrPSc) of the host-encoded cellular prion protein (PrPC). PrPSc conformation to disease phenotype relationships extensively vary among prion strains. In particular, prions exhibit a strain-dependent tropism for lymphoid tissues. Prions can be composed of several substrain components. There is evidence that these substrains can propagate in distinct tissues (e.g. brain and spleen) of a single individual, providing an experimental paradigm to study the cause of prion tissue selectivity. Previously, we showed that PrPC expression levels feature in prion substrain selection in the brain. Transmission of sheep scrapie isolates (termed LAN) to multiple lines of transgenic mice expressing varying levels of ovine PrPC in their brains resulted in the phenotypic expression of the dominant sheep substrain in mice expressing near physiological PrPC levels, whereas a minor substrain replicated preferentially on high expresser mice. Considering that PrPC expression levels are markedly decreased in the spleen compared to the brain, we interrogate whether spleen PrPC dosage could drive prion selectivity. The outcome of the transmission of a large cohort of LAN isolates in the spleen from high expresser mice correlated with the replication rate dependency on PrPC amount. There was a prominent spleen colonization by the substrain preferentially replicating on low expresser mice and a relative incapacity of the substrain with higher-PrPC level need to propagate in the spleen. Early colonization of the spleen after intraperitoneal inoculation allowed neuropathological expression of the lymphoid substrain. In addition, a pair of substrain variants resulting from the adaptation of human prions to ovine high expresser mice, and exhibiting differing brain versus spleen tropism, showed different tropism on transmission to low expresser mice, with the lymphoid substrain colonizing the brain. Overall, these data suggest that PrPC expression levels are instrumental in prion lymphotropism. The cause of prion phenotype variation among prion strains remains poorly understood. In particular, prions replicate in a strain-dependent manner in the spleen. This can result in prion asymptomatic carriers. Based on our previous observations that dosage of the prion precursor (PrP) determined prion substrain selection in the brain, we examine whether PrP levels in the spleen could drive prion replication in this tissue, due to the low levels of the protein. We observe that the prion substrain with higher PrP need for replication does barely replicate in the spleen, while the component with low PrP need replicates efficiently. In addition, other human co-propagating prions with differing spleen and brain tropism showed different tropism on transmission to mice expressing low PrP levels, with the lymphoid substrain colonizing the brain. PrPC expression levels may thus be instrumental in prion tropism for the lymphoid tissue. From a diagnostic point of view, given the apparent complexity of prion diseases with respect to prion substrain composition, these data advocate to type extraneural tissues or fluids for a comprehensive identification of the circulating prions in susceptible mammals.
Collapse
Affiliation(s)
- Vincent Béringue
- Université Paris-Saclay, INRAE, UVSQ, VIM Jouy-en-Josas, France
- * E-mail:
| | | | | | - Fabienne Reine
- Université Paris-Saclay, INRAE, UVSQ, VIM Jouy-en-Josas, France
| | - Johan Castille
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, Jouy-en-Josas, France
| | - Thanh-Lan Laï
- Université Paris-Saclay, INRAE, UVSQ, VIM Jouy-en-Josas, France
| | - Annick Le Dur
- Université Paris-Saclay, INRAE, UVSQ, VIM Jouy-en-Josas, France
| | - Aude Laisné
- Université Paris-Saclay, INRAE, UVSQ, VIM Jouy-en-Josas, France
| | - Laetitia Herzog
- Université Paris-Saclay, INRAE, UVSQ, VIM Jouy-en-Josas, France
| | - Bruno Passet
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, Jouy-en-Josas, France
| | - Human Rezaei
- Université Paris-Saclay, INRAE, UVSQ, VIM Jouy-en-Josas, France
| | - Jean-Luc Vilotte
- Université Paris-Saclay, INRAE, AgroParisTech, GABI, Jouy-en-Josas, France
| | - Hubert Laude
- Université Paris-Saclay, INRAE, UVSQ, VIM Jouy-en-Josas, France
| |
Collapse
|
2
|
Favole A, Mazza M, Vallino Costassa E, D'Angelo A, Lombardi G, Marconi P, Crociara P, Berrone E, Gallo M, Palmitessa C, Orrù CD, Caughey B, Acutis PL, Caramelli M, Casalone C, Corona C. Early and Pre-Clinical Detection of Prion Seeding Activity in Cerebrospinal Fluid of Goats using Real-Time Quaking-Induced Conversion Assay. Sci Rep 2019; 9:6173. [PMID: 30992522 PMCID: PMC6467873 DOI: 10.1038/s41598-019-42449-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 03/27/2019] [Indexed: 12/04/2022] Open
Abstract
Since 2005, two cases of natural bovine spongiform encephalopathies (BSE) have been reported in goats. Furthermore, experimental transmissions of classical (C-BSE) and atypical (L-BSE) forms of BSE in goats were also reported. To minimize further spreading of prion diseases in small ruminants the development of a highly sensitive and specific test for ante-mortem detection of infected animals would be of great value. Recent studies reported high diagnostic value of a second generation of cerebrospinal fluid (CSF) Real-Time Quaking-Induced Conversion (RT-QuIC) assay across a wide spectrum of human prions. Here, we applied this improved QuIC (IQ-CSF) for highly efficient detection of TSEs prion protein in goat cerebrospinal fluid. IQ-CSF sensitivity and specificity were evaluated on CSF samples collected at disease endpoint from goats naturally and experimentally infected with scrapie or bovine isolates of C-BSE and L-BSE, respectively. Next, CSF samples collected from L-BSE infected goats during pre-symptomatic stage were also analysed. PrPL-BSE associated seeding activity was detected at early time points after experimental inoculation, with an average time of 439 days before clinical symptoms appeared. Taken together these data are indicative of the great potential of this in vitro prion amplification assay as ante-mortem TSE test for live and asymptomatic small ruminants.
Collapse
Affiliation(s)
- Alessandra Favole
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Maria Mazza
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Elena Vallino Costassa
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Antonio D'Angelo
- Dipartimento di Scienze Veterinarie, Sezione Clinica Medica, University of Turin, Grugliasco, Turin, Italy
| | - Guerino Lombardi
- Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia, Italy
| | - Paola Marconi
- Istituto Zooprofilattico Sperimentale Lazio e Toscana, Firenze, Italy
| | - Paola Crociara
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Elena Berrone
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Marina Gallo
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Claudia Palmitessa
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Christina D Orrù
- Rocky Mountain Laboratories, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Byron Caughey
- Rocky Mountain Laboratories, National Institute for Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA
| | - Pier L Acutis
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Maria Caramelli
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Cristina Casalone
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy
| | - Cristiano Corona
- National Reference Laboratory of TSEs (CEA), Istituto Zooprofilattico Sperimentale del Piemonte, Liguria e Valle d'Aosta, Turin, Italy.
| |
Collapse
|
3
|
Hedman C, Otero A, Douet JY, Lacroux C, Lugan S, Filali H, Corbière F, Aron N, Badiola JJ, Andréoletti O, Bolea R. Detection of PrPres in peripheral tissue in pigs with clinical disease induced by intracerebral challenge with sheep-passaged bovine spongiform encephalopathy agent. PLoS One 2018; 13:e0199914. [PMID: 29975760 PMCID: PMC6033439 DOI: 10.1371/journal.pone.0199914] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 06/16/2018] [Indexed: 11/21/2022] Open
Abstract
Bovine spongiform encephalopathy (BSE) can be efficiently transmitted to pigs via intracerebral inoculation. A clear link has been established between the consumption of products of bovine origin contaminated with the BSE agent and the development of variant Creutzfeldt-Jakob disease in humans. Small ruminants can also naturally develop BSE, and sheep-adapted BSE (Sh-BSE) propagates more efficiently than cattle BSE in pigs and in mouse models expressing porcine prion protein. In addition, Sh-BSE shows greater efficiency of transmission to human models than original cow BSE. While infectivity and/or abnormal PrP accumulation have been reported in the central nervous system in BSE-infected pigs, the ability of the agent to replicate in peripheral tissues has not been fully investigated. We previously characterized the presence of prions in a panel of tissues collected at the clinical stage of disease from pigs experimentally infected with Sh-BSE. Western blot revealed low levels of PrPres accumulation in lymphoid tissues, nerves, and skeletal muscles from 4 of the 5 animals analysed. Using protein misfolding cyclic amplification (PMCA), which we found to be 6 log fold more sensitive than direct WB for the detection of pig BSE, we confirmed the presence of the Sh-BSE agent in lymphoid organs, nerves, ileum, and striated muscles from all 5 inoculated pigs. Surprisingly, PrPres positivity was also detected in white blood cells from one pig using this method. The presence of infectivity in lymphoid tissues, striated muscles, and peripheral nerves was confirmed by bioassay in bovine PrP transgenic mice. These results demonstrate the ability of BSE-derived agents to replicate efficiently in various peripheral tissues in pigs. Although no prion transmission has been reported in pigs following oral BSE challenge, our data support the continuation of the Feed Ban measure implemented to prevent entry of the BSE agent into the feed chain.
Collapse
Affiliation(s)
- Carlos Hedman
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Veterinary Faculty, Universidad de Zaragoza, Zaragoza, Spain
| | - Alicia Otero
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Veterinary Faculty, Universidad de Zaragoza, Zaragoza, Spain
| | - Jean-Yves Douet
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Caroline Lacroux
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Séverine Lugan
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Hicham Filali
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Veterinary Faculty, Universidad de Zaragoza, Zaragoza, Spain
| | - Fabien Corbière
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Naima Aron
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Juan José Badiola
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Veterinary Faculty, Universidad de Zaragoza, Zaragoza, Spain
| | - Olivier Andréoletti
- UMR INRA ENVT 1225, Interactions Hôtes Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, Toulouse, France
| | - Rosa Bolea
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Veterinary Faculty, Universidad de Zaragoza, Zaragoza, Spain
- * E-mail:
| |
Collapse
|
4
|
Ritchie DL, Adlard P, Peden AH, Lowrie S, Le Grice M, Burns K, Jackson RJ, Yull H, Keogh MJ, Wei W, Chinnery PF, Head MW, Ironside JW. Amyloid-β accumulation in the CNS in human growth hormone recipients in the UK. Acta Neuropathol 2017; 134:221-240. [PMID: 28349199 PMCID: PMC5508038 DOI: 10.1007/s00401-017-1703-0] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 03/15/2017] [Accepted: 03/18/2017] [Indexed: 12/31/2022]
Abstract
Human-to-human transmission of Creutzfeldt-Jakob disease (CJD) has occurred through medical procedures resulting in iatrogenic CJD (iCJD). One of the commonest causes of iCJD was the use of human pituitary-derived growth hormone (hGH) to treat primary or secondary growth hormone deficiency. As part of a comprehensive tissue-based analysis of the largest cohort yet collected (35 cases) of UK hGH-iCJD cases, we describe the clinicopathological phenotype of hGH-iCJD in the UK. In the 33/35 hGH-iCJD cases with sufficient paraffin-embedded tissue for full pathological examination, we report the accumulation of the amyloid beta (Aβ) protein associated with Alzheimer's disease (AD) in the brains and cerebral blood vessels in 18/33 hGH-iCJD patients and for the first time in 5/12 hGH recipients who died from causes other than CJD. Aβ accumulation was markedly less prevalent in age-matched patients who died from sporadic CJD and variant CJD. These results are consistent with the hypothesis that Aβ, which can accumulate in the pituitary gland, was present in the inoculated hGH preparations and had a seeding effect in the brains of around 50% of all hGH recipients, producing an AD-like neuropathology and cerebral amyloid angiopathy (CAA), regardless of whether CJD neuropathology had occurred. These findings indicate that Aβ seeding can occur independently and in the absence of the abnormal prion protein in the human brain. Our findings provide further evidence for the prion-like seeding properties of Aβ and give insights into the possibility of iatrogenic transmission of AD and CAA.
Collapse
Affiliation(s)
- Diane L Ritchie
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK.
| | - Peter Adlard
- UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK
| | - Alexander H Peden
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Suzanne Lowrie
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Margaret Le Grice
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Kimberley Burns
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Rosemary J Jackson
- Centre for Cognitive and Neural Systems, University of Edinburgh, 1 George Square, Edinburgh, EH8 9JZ, UK
| | - Helen Yull
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Michael J Keogh
- Department of Clinical Neurosciences, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0QQ, UK
| | - Wei Wei
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Patrick F Chinnery
- MRC Mitochondrial Biology Unit, University of Cambridge, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Mark W Head
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - James W Ironside
- National CJD Research & Surveillance Unit, Centre for Clinical Brain Sciences, Deanery of Clinical Medicine, University of Edinburgh, Edinburgh, EH4 2XU, UK
| |
Collapse
|
5
|
Abstract
Prion diseases affect a wide range of mammal species and are caused by a misfolded self-propagating isoform (PrPSc) of the normal prion protein (PrPC). Distinct strains of prions exist and are operationally defined by differences in a heritable phenotype under controlled experimental transmission conditions. Prion strains can differ in incubation period, clinical signs of disease, tissue tropism, and host range. The mechanism by which a protein-only pathogen can encode strain diversity is only beginning to be understood. The prevailing hypothesis is that prion strain diversity is encoded by strain-specific conformations of PrPSc; however, strain-specific cellular cofactors have been identified in vitro that may also contribute to prion strain diversity. Although much progress has been made on understanding the etiological agent of prion disease, the relationship between the strain-specific properties of PrPSc and the resulting phenotype of disease in animals is poorly understood.
Collapse
Affiliation(s)
- Jason C Bartz
- Department of Medical Microbiology and Immunology, School of Medicine, Creighton University, Omaha, Nebraska 68178
| |
Collapse
|
6
|
Hilton KJ, Cunningham C, Reynolds RA, Perry VH. Early Hippocampal Synaptic Loss Precedes Neuronal Loss and Associates with Early Behavioural Deficits in Three Distinct Strains of Prion Disease. PLoS One 2013; 8:e68062. [PMID: 23840812 PMCID: PMC3694005 DOI: 10.1371/journal.pone.0068062] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Accepted: 05/24/2013] [Indexed: 11/18/2022] Open
Abstract
Prion diseases are fatal neurodegenerative diseases of the CNS that are associated with the accumulation of misfolded cellular prion protein. There are several different strains of prion disease defined by different patterns of tissue vacuolation in the brain and disease time course, but features of neurodegeneration in these strains have not been extensively studied. Our previous studies using the prion strains ME7, 79A and 22L showed that infected mice developed behavioural deficits in the same sequence and temporal pattern despite divergent end-stage neuropathology. Here the objective was to address the hypothesis that synaptic loss would occur early in the disease in all three strains, would precede neuronal death and would be associated with the early behavioural deficits. C57BL/6 mice inoculated with ME7, 79A, or 22L-infected brain homogenates were behaviourally assessed on species typical behaviours previously shown to change during progression and euthanised when all three strains showed statistically significant impairment on these tasks. A decrease in labelling with the presynaptic marker synaptophysin was observed in the stratum radiatum of the hippocampus in all three strains, when compared to control animals. Negligible cell death was seen by TUNEL at this time point. Astrocyte and microglial activation and protease resistant prion protein (PrPSc) deposition were assessed in multiple brain regions and showed some strain specificity but also strongly overlapping patterns. This study shows that despite distinct pathology, multiple strains lead to early synaptic degeneration in the hippocampus, associated with similar behavioural deficits and supports the idea that the initiation of synaptic loss is a primary target of the misfolded prion agent.
Collapse
Affiliation(s)
- Kathryn J. Hilton
- School of Biological Sciences, Southampton General Hospital, Southampton, United Kingdom
| | - Colm Cunningham
- Trinity College Institute of Neuroscience & School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland
- * E-mail:
| | - Richard A. Reynolds
- School of Biological Sciences, Southampton General Hospital, Southampton, United Kingdom
| | - V. Hugh Perry
- School of Biological Sciences, Southampton General Hospital, Southampton, United Kingdom
| |
Collapse
|
7
|
Piercey Åkesson C, Press CM, Tranulis MA, Jeffrey M, Aleksandersen M, Landsverk T, Espenes A. Phenotypic characterization of cells participating in transport of prion protein aggregates across the intestinal mucosa of sheep. Prion 2012; 6:261-75. [PMID: 22437736 PMCID: PMC3399537 DOI: 10.4161/pri.19215] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The oral route is considered to be the main entry site of several transmissible spongiform encephalopathies or prion diseases of animals and man. Following natural and experimental oral exposure to scrapie, sheep first accumulate disease associated prion protein (PrPd) in Peyer’s patch (PP) lymphoid follicles. In this study, recombinant ovine prion protein (rPrP) was inoculated into gut loops of young lambs and the transportation across the intestinal wall studied. In particular, the immunohistochemical phenotypes of cells bearing the inoculated prion protein were investigated. The rPrP was shown to be transported across the villi of the gut, into the lacteals and submucosal lymphatics, mimicking the transport route of PrPd from scrapie brain inoculum observed in a previous intestinal loop experiment. The cells bearing the inoculated rPrP were mainly mononuclear cells, and multicolor immunofluorescence procedures were used to show that the rPrP bearing cells were professional antigen presenting cells expressing Major histocompatibility complex II (MHCII). In addition, the rPrP bearing cells labeled with CD205, CD11b and the macrophage marker CD68, and not with the dendritic cell markers CD11c and CD209. Others have reported that cells expressing CD205 and CD11b in the absence of CD11c have been shown to induce T cell tolerance or regulatory T cells. Based on this association, it was speculated that the rPrP and by extension PrPd and scrapie infective material may exploit the physiological process of macromolecular uptake across the gut, and that this route of entry may have implications for immune surveillance.
Collapse
Affiliation(s)
- Caroline Piercey Åkesson
- Department of Basic Sciences and Aquatic Medicine, Norwegian School of Veterinary Science, Oslo, Norway.
| | | | | | | | | | | | | |
Collapse
|
8
|
Arnold ME, Hawkins SAC, Green R, Dexter I, Wells GAH. Pathogenesis of experimental bovine spongiform encephalopathy (BSE): estimation of tissue infectivity according to incubation period. Vet Res 2009; 40:8. [PMID: 18950589 PMCID: PMC2695012 DOI: 10.1051/vetres:2008046] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Accepted: 10/23/2008] [Indexed: 11/14/2022] Open
Abstract
This paper reports the results of tissue infectivity assays of bovine spongiform encephalopathy (BSE) agent in orally exposed cattle at stages during the incubation period. Estimations of the titre of infectivity in central nervous system (CNS), certain peripheral nerve ganglia and distal ileum tissue were made according to time post exposure from the relationship between incubation period and dose for RIII mice and C57bl mice using data from titrations of brain material from cases of BSE. The rate of increase of infectivity in the bovine CNS was then estimated, taking into account these tissue infectivity titres, the variability of the brain titre of clinical field cases of BSE, and the probability density of the expected number of months before clinical onset of each infected bovine. The doubling time for CNS was shown to equal 1.2 months. The titre in the thoracic dorsal root ganglia (DRG) was, on average, approximately 1 log units less than CNS, and cervical DRG approximately 0.5 log less than thoracic DRG. The pattern of increase of infectivity in the distal ileum is that of an initial increase up to 14-18 months post exposure, followed by a decrease, which is likely to be highly variable between animals. These results will be informative for future risk assessments of BSE, especially in relation to reviewing current control measures.
Collapse
Affiliation(s)
- Mark Edward Arnold
- Veterinary Laboratories Agency, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom.
| | | | | | | | | |
Collapse
|
9
|
Brandner S, Whitfield J, Boone K, Puwa A, O'Malley C, Linehan JM, Joiner S, Scaravilli F, Calder I, P Alpers M, Wadsworth JDF, Collinge J. Central and peripheral pathology of kuru: pathological analysis of a recent case and comparison with other forms of human prion disease. Philos Trans R Soc Lond B Biol Sci 2008; 363:3755-63. [PMID: 18849292 PMCID: PMC2581659 DOI: 10.1098/rstb.2008.0091] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
While the neuropathology of kuru is well defined, there are few data concerning the distribution of disease-related prion protein in peripheral tissues. Here we report the investigation of brain and peripheral tissues from a kuru patient who died in 2003. Neuropathological findings were compared with those seen in classical (sporadic and iatrogenic) Creutzfeldt–Jakob disease (CJD) and variant CJD (vCJD). The neuropathological findings of the kuru patient showed all the stereotypical changes that define kuru, with the occurrence of prominent PrP plaques throughout the brain. Lymphoreticular tissue showed no evidence of prion colonization, suggesting that the peripheral pathogenesis of kuru is similar to that seen in classical CJD rather than vCJD. These findings now strongly suggest that the characteristic peripheral pathogenesis of vCJD is determined by prion strain type alone rather than route of infection.
Collapse
Affiliation(s)
- Sebastian Brandner
- Department of Neurodegenerative Disease, MRC Prion Unit, UCL Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Abstract
While neuropathological features that define prion strains include spongiform degeneration and deposition patterns of PrP(Sc), the underlying mechanism for the strain-specific differences in PrP(Sc) targeting is not known. To investigate prion strain targeting, we inoculated hamsters in the sciatic nerve with either the hyper (HY) or drowsy (DY) strain of the transmissible mink encephalopathy (TME) agent. Both TME strains were initially retrogradely transported in the central nervous system (CNS) exclusively by four descending motor tracts. The locations of HY and DY PrP(Sc) deposition were identical throughout the majority of the incubation period. However, differences in PrP(Sc) deposition between these strains were observed upon development of clinical disease. The differences observed were unlikely to be due to strain-specific neuronal tropism, since comparison of PrP(Sc) deposition patterns by different routes of infection indicated that all brain areas were susceptible to prion infection by both TME strains. These findings suggest that prion transport and differential susceptibility to prion infection are not solely responsible for prion strain targeting. The data suggest that differences in PrP(Sc) distribution between strains during clinical disease are due to differences in the length of time that PrP(Sc) has to spread in the CNS before the host succumbs to disease.
Collapse
|
11
|
Crossing the species barrier by PrP(Sc) replication in vitro generates unique infectious prions. Cell 2008; 134:757-68. [PMID: 18775309 DOI: 10.1016/j.cell.2008.07.030] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2007] [Revised: 05/08/2008] [Accepted: 07/21/2008] [Indexed: 11/24/2022]
Abstract
Prions are unconventional infectious agents composed exclusively of misfolded prion protein (PrP(Sc)), which transmits the disease by propagating its abnormal conformation to the cellular prion protein (PrP(C)). A key characteristic of prions is their species barrier, by which prions from one species can only infect a limited number of other species. Here, we report the generation of infectious prions by interspecies transmission of PrP(Sc) misfolding by in vitro PMCA amplification. Hamster PrP(C) misfolded by mixing with mouse PrP(Sc) generated unique prions that were infectious to wild-type hamsters, and similar results were obtained in the opposite direction. Successive rounds of PMCA amplification result in adaptation of the in vitro-produced prions, in a process reminiscent of strain stabilization observed upon serial passage in vivo. Our results indicate that PMCA is a valuable tool for the investigation of cross-species transmission and suggest that species barrier and strain generation are determined by the propagation of PrP misfolding.
Collapse
|
12
|
Abstract
Despite important progress in experimental treatment of neurodegenerative diseases, no therapeutic strategy has today proven its capability to cure or even to stabilise human TSEs. Pathogenesis experiments performed in rodent TSE models have shown that central nervous system damages are detectable long before the appearance of the clinical symptoms. At the time of disease onset, PrP(Sc) accumulation has almost reached its highest level, and the neuropathological lesions (spongiosis, gliosis) are as intense as they are at the time of death. Therefore, the neurodegeneration that is present at the onset of the disease is beyond therapy, and, in theory, only a preclinical diagnosis of TSEs would permit the prevention (or delay) of neurodegeneration. Unfortunately, there are no diagnostic tests that can be used to show TSE agent infection during the preclinical phase of the disease. Nevertheless, since the appearance of variant Creutzfeldt-Jakob disease (vCJD), those in the scientific community working on experimental therapy have increased their efforts. Tens of drugs have been tested in several experimental models, and there are some high-output screening platforms being used in Europe and in the US. Any rational therapeutic strategy needs to be based on pathogenesis data and/or knowledge on the nature of the causative agent. Therefore, progress in therapy is tightly linked to a better understanding of the basic science of TSE.
Collapse
Affiliation(s)
- Dominique Dormont
- Service de Neurovirologie, CEA, CRSSA, EPHE, Univeristé Paris XI, Fontenay-aux-Roses, France
| |
Collapse
|
13
|
Abstract
Prion diseases or transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative diseases, clinically characterised by cognitive decline, paralleled by severe damage to the central nervous system. Prion diseases have attracted a broad interest because of their unique mechanisms of replication and propagation; however, the underlying pathogenic mechanisms are still highly speculative. In this review, current knowledge about the pathogenesis of prion diseases in the CNS will be highlighted and the most revealing animal models will be discussed, with future perspectives to address immediate questions about the pathogenesis.
Collapse
Affiliation(s)
- Sebastian Brandner
- MRC Prion Unit, Department of Neurodegenerative Diseases, Institute of Neurology, London, UK
| |
Collapse
|
14
|
Cardone F, Pocchiari M. A role for complement in transmissible spongiform encephalopathies. Nat Med 2001; 7:410-1. [PMID: 11283661 DOI: 10.1038/86469] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
15
|
Beringue V, Adjou KT, Lamoury F, Maignien T, Deslys JP, Race R, Dormont D. Opposite effects of dextran sulfate 500, the polyene antibiotic MS-8209, and Congo red on accumulation of the protease-resistant isoform of PrP in the spleens of mice inoculated intraperitoneally with the scrapie agent. J Virol 2000; 74:5432-40. [PMID: 10823847 PMCID: PMC112027 DOI: 10.1128/jvi.74.12.5432-5440.2000] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The mode and the site of action of the major antiscrapie drugs have been studied by investigating their effects on the abnormal protease-resistant isoform of PrP (PrPres) and on its accumulation in mouse spleen. Day-by-day PrPres accumulation in the spleen and in other peripheral organs was first monitored to describe the early steps of scrapie pathogenesis. Three phases were identified: the detection of scrapie inoculum on the day of scrapie infection, a clearance phase, and then the peripheral accumulation of PrPres. In a second step, the effects of the polyene antibiotic MS-8209, the polyanion dextran sulfate 500 (DS500), and Congo red were assessed on these phases, after the drugs were coincubated with scrapie inoculum. Highly different mechanisms and sites of action were apparent. MS-8209 had a weak effect on the accumulation of PrPres in spleen, suggesting another site of intervention for this drug. DS500 delayed the beginning of the clearance phase but then blocked PrPres synthesis for a long period of time, probably because of its immunological effects on the spleen. Surprisingly, Congo red suppressed the clearance phase of scrapie inoculum and then increased transiently accumulation of PrPres in spleen. We showed in vitro that this effect was related to a direct enhancement of the protease resistance of PrPres by the drug.
Collapse
Affiliation(s)
- V Beringue
- CEA, Service de Neurovirologie, DRM/DSV, CRSSA, Fontenay aux Roses, France.
| | | | | | | | | | | | | |
Collapse
|
16
|
Ghani AC, Ferguson NM, Donnelly CA, Hagenaars TJ, Anderson RM. Epidemiological determinants of the pattern and magnitude of the vCJD epidemic in Great Britain. Proc Biol Sci 1998; 265:2443-52. [PMID: 9921684 PMCID: PMC1689535 DOI: 10.1098/rspb.1998.0596] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Understanding the epidemiology and aetiology of new-variant Creutzfeldt-Jakob (vCJD) disease in humans has become increasingly important given the scientific evidence linking it to bovine spongiform encephalopathy (BSE) in cattle and hence the wide exposure of the population of Great Britain (GB) to potentially infectious tissue. The recent analysis undertaken to determine the risk to the population from dorsal route ganglia illustrated the danger in presenting point estimates rather than ranges of scenarios in the face of uncertainty. We present a mathematical template that relates the past pattern of the BSE epidemic in cattle to the future course of any vCJD epidemic in humans, and use extensive scenario analysis to explore the wide range of possible outcomes given the uncertainty in epidemiological determinants. We demonstrate that the average number of humans infected by one infectious bovine and the incubation period distribution are the two epidemiological factors that have the greatest impact on epidemic size and duration. Using the time-series of the BSE epidemic and the cases seen to date, we show that the minimum length of the incubation period is approximately nine years, and that at least 20% of the cases diagnosed to date were exposed prior to 1986. We also demonstrate that the current age distribution of vCJD cases can only arise if younger people were either exposed to a greater extent, more susceptible to infection, or have shorter incubation periods. Extensive scenario analyses show that given the information currently available, the very high degree of uncertainty in the future size of the epidemic will remain for the next 3-5 years. Furthermore, we demonstrate that this uncertainty is unlikely to be reduced by mass screening for late-stage infection.
Collapse
Affiliation(s)
- A C Ghani
- Wellcome Trust Centre for the Epidemiology of Infectious Disease, Department of Zoology, University of Oxford, UK.
| | | | | | | | | |
Collapse
|
17
|
Affiliation(s)
- M Pocchiari
- Section of Persistent and Slow Virus Infections, Istituto Superiore di Sanità, Rome, Italy
| |
Collapse
|