1
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Abstract
Transmissible spongiform encephalopathies (TSEs) are inevitably lethal neurodegenerative diseases that affect humans and a large variety of animals. The infectious agent responsible for TSEs is the prion, an abnormally folded and aggregated protein that propagates itself by imposing its conformation onto the cellular prion protein (PrPC) of the host. PrPCis necessary for prion replication and for prion-induced neurodegeneration, yet the proximal causes of neuronal injury and death are still poorly understood. Prion toxicity may arise from the interference with the normal function of PrPC, and therefore, understanding the physiological role of PrPCmay help to clarify the mechanism underlying prion diseases. Here we discuss the evolution of the prion concept and how prion-like mechanisms may apply to other protein aggregation diseases. We describe the clinical and the pathological features of the prion diseases in human and animals, the events occurring during neuroinvasion, and the possible scenarios underlying brain damage. Finally, we discuss potential antiprion therapies and current developments in the realm of prion diagnostics.
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2
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Bremer J, Heikenwalder M, Haybaeck J, Tiberi C, Krautler NJ, Kurrer MO, Aguzzi A. Repetitive immunization enhances the susceptibility of mice to peripherally administered prions. PLoS One 2009; 4:e7160. [PMID: 19779609 PMCID: PMC2744926 DOI: 10.1371/journal.pone.0007160] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Accepted: 08/25/2009] [Indexed: 02/07/2023] Open
Abstract
The susceptibility of humans and animals to prion infections is determined by the virulence of the infectious agent, by genetic modifiers, and by hitherto unknown host and environmental risk factors. While little is known about the latter two, the activation state of the immune system was surmised to influence prion susceptibility. Here we administered prions to mice that were repeatedly immunized by two initial injections of CpG oligodeoxynucleotides followed by repeated injections of bovine serum albumin/alum. Immunization greatly reduced the required dosage of peripherally administered prion inoculum necessary to induce scrapie in 50% of mice. No difference in susceptibility was observed following intracerebral prion challenge. Due to its profound impact onto scrapie susceptibility, the host immune status may determine disease penetrance after low-dose prion exposure, including those that may give rise to iatrogenic and variant Creutzfeldt-Jakob disease.
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Affiliation(s)
- Juliane Bremer
- Institute of Neuropathology, Department of Pathology, University Hospital of Zurich, Zurich, Switzerland
| | - Mathias Heikenwalder
- Institute of Neuropathology, Department of Pathology, University Hospital of Zurich, Zurich, Switzerland
| | - Johannes Haybaeck
- Institute of Neuropathology, Department of Pathology, University Hospital of Zurich, Zurich, Switzerland
| | - Cinzia Tiberi
- Institute of Neuropathology, Department of Pathology, University Hospital of Zurich, Zurich, Switzerland
| | - Nike Julia Krautler
- Institute of Neuropathology, Department of Pathology, University Hospital of Zurich, Zurich, Switzerland
| | | | - Adriano Aguzzi
- Institute of Neuropathology, Department of Pathology, University Hospital of Zurich, Zurich, Switzerland
- * E-mail:
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3
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Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, University of Zurich, CH-8091 Zurich, Switzerland,
| | - Frank Baumann
- Institute of Neuropathology, University of Zurich, CH-8091 Zurich, Switzerland,
| | - Juliane Bremer
- Institute of Neuropathology, University of Zurich, CH-8091 Zurich, Switzerland,
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4
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Aguzzi A, Sigurdson C, Heikenwaelder M. Molecular mechanisms of prion pathogenesis. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2008; 3:11-40. [PMID: 18233951 DOI: 10.1146/annurev.pathmechdis.3.121806.154326] [Citation(s) in RCA: 253] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Prion diseases are infectious neurodegenerative diseases occurring in humans and animals with an invariably lethal outcome. One fundamental mechanistic event in prion diseases is the aggregation of aberrantly folded prion protein into large amyloid plaques and fibrous structures associated with neurodegeneration. The cellular prion protein (PrPC) is absolutely required for disease development, and prion knockout mice are not susceptible to prion disease. Prions accumulate not only in the central nervous system but also in lymphoid organs, as shown for new variant and sporadic Creutzfeldt-Jakob patients and for some animals. To date it is largely accepted that prions consist primarily of PrPSc, a misfolded and aggregated beta-sheet-rich isoform of PrPC. However, PrPSc may or may not be completely congruent with the infectious moiety. Here, we discuss the molecular mechanisms leading to neurodegeneration, the role of the immune system in prion pathogenesis, and the existence of prion strains that appear to have different tropisms and biochemical characteristics.
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Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zürich, CH-8091 Zürich, Switzerland.
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5
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Geissen M, Krasemann S, Matschke J, Glatzel M. Understanding the natural variability of prion diseases. Vaccine 2007; 25:5631-6. [PMID: 17391814 DOI: 10.1016/j.vaccine.2007.02.041] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2006] [Revised: 01/16/2007] [Accepted: 02/15/2007] [Indexed: 11/24/2022]
Abstract
Prion diseases are a heterogeneous group of disorders with an invariably fatal disease course. Although various etiologies have been proposed it is apparent that at least a subset of these diseases are of infectious nature. An essential part of the infectious agent, termed the prion, is mainly composed of an abnormal isoform (PrP(Sc)) of a host-encoded normal cellular protein (PrP(C)). The molecular details of the pathophysiology of this group of diseases are unclear but the conversion of PrP(C) to PrP(Sc) plays a fundamental role. In all human prion diseases, PrP(Sc) is deposited in the central nervous system. These disorders include sporadic, genetic and acquired Creutzfeldt-Jakob disease. The molecular classification of human prion diseases is important in order to understand underlying disease mechanisms and for the development of novel therapy protocols. Current classification systems are based on the assessment of clinical presentation, genetic investigations, neuropathological findings and biochemical analysis of PrP(Sc).
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Affiliation(s)
- Markus Geissen
- Institute of Neuropathology, Universitätsklinikum Hamburg-Eppendorf, 20246 Hamburg, Germany
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6
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Prion Diseases. Neurobiol Dis 2007. [DOI: 10.1016/b978-012088592-3/50044-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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7
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Aguzzi A, Glatzel M. Prion infections, blood and transfusions. ACTA ACUST UNITED AC 2006; 2:321-9. [PMID: 16932576 DOI: 10.1038/ncpneuro0214] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2006] [Accepted: 04/04/2006] [Indexed: 12/17/2022]
Abstract
Prion infections lead to invariably fatal diseases of the CNS, including Creutzfeldt-Jakob disease (CJD) in humans, bovine spongiform encephalopathy (BSE), and scrapie in sheep. There have been hundreds of instances in which prions have been transmitted iatrogenically among humans, usually through neurosurgical procedures or administration of pituitary tissue extracts. Prions have not generally been regarded as blood-borne infectious agents, and case-control studies have failed to identify CJD in transfusion recipients. Previous understanding was, however, questioned by reports of prion infections in three recipients of blood donated by individuals who subsequently developed variant CJD. On reflection, hematogenic prion transmission does not come as a surprise, as involvement of extracerebral compartments such as lymphoid organs and skeletal muscle is common in most prion infections, and prions have been recovered from the blood of rodents and sheep. Novel diagnostic strategies, which might include the use of surrogate markers of prion infection, along with prion removal strategies, might help to control the risk of iatrogenic prion spread through blood transfusions.
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Affiliation(s)
- Adriano Aguzzi
- Department of Pathology, Zürich University, Switzerland.
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8
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Raeber AJ, Brandner S, Klein MA, Benninger Y, Musahl C, Frigg R, Roeckl C, Fischer MB, Weissmann C, Aguzzi A. Transgenic and knockout mice in research on prion diseases. Brain Pathol 2006; 8:715-33. [PMID: 9804380 PMCID: PMC8098451 DOI: 10.1111/j.1750-3639.1998.tb00197.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Since the discovery of the prion protein (PrP) gene more than a decade ago, transgenetic investigations on the PrP gene have shaped the field of prion biology in an unprecedented way. Many questions regarding the role of PrP in susceptibility of an organism exposed to prions have been elucidated. For example mice with a targeted disruption of the PrP gene have allowed the demonstration that an organism that lacks PrPc is resistant to infection by prions. Reconstitution of these mice with mutant PrP genes allowed investigations on the structure-activity relationship of the PrP gene with regard to scrapie susceptibility. Unexpectedly, transgenic mice expressing PrP with specific amino-proximal truncations spontaneously develop a neurologic syndrome presenting with ataxia and cerebellar lesions. A distinct spontaneous neurologic phenotype was observed in mice with internal deletions in PrP. Using ectopic expression of PrP in PrP knockout mice has turned out to be a valuable approach towards the identification of host cells that are capable of replicating prions. Transgenic mice have also contributed to our understanding of the molecular basis of the species barrier for prions. Finally, the availability of PrP knockout mice and transgenic mice overexpressing PrP allows selective reconstitution experiments aimed at expressing PrP in neurografts or in specific populations of hemato- and lymphopoietic cells. Such studies have shed new light onto the mechanisms of prion spread and disease pathogenesis.
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Affiliation(s)
- A J Raeber
- Institute of Neuropathology, Department of Pathology, University Hospital, Zürich, Switzerland.
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9
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Prion diseases. NEURODEGENER DIS 2005. [DOI: 10.1017/cbo9780511544873.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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10
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Genoud N, Behrens A, Arrighi I, Aguzzi A. Prion proteins and infertility: insight from mouse models. Cytogenet Genome Res 2004; 103:285-9. [PMID: 15051949 DOI: 10.1159/000076814] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2003] [Accepted: 11/04/2003] [Indexed: 11/19/2022] Open
Abstract
A wealth of evidence points to an abnormal form of the prion protein called PrP(Sc) as the transmissible agent responsible for prion diseases. However, the physiological function of its normal conformer, the cellular prion protein (PrP(C)), is still unknown. Recently, a homologue of PrP(C) was discovered and denoted Doppel (Dpl). In contrast to PrP, mice deficient for Dpl suffer from an important pathological phenotype: male sterility. This phenotype shifts the attention from the brain, where most of the investigations on Dpl have been performed, to testis, raising hope to resolve the long lasting search of PrP(C) function.
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Affiliation(s)
- N Genoud
- Institute of Neuropathology, UniversitätsSpital Zurich, Zurich, Switzerland
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11
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Abstract
Prions have been responsible for an entire century of tragic episodes. Fifty years ago, kuru decimated the population of Papua New Guinea. Then, iatrogenic transmission of prions caused more than 250 cases of Creutzfeldt-Jakob disease. More recently, transmission of bovine spongiform encephalopathy to humans caused a widespread health scare. On the other hand, the biology of prions represents a fascinating and poorly understood phenomenon, which may account for more than just diseases and may represent a fundamental mechanism of crosstalk between proteins. The two decades since Stanley Prusiner's formulation of the protein-only hypothesis have witnessed spectacular advances, and yet some of the most basic questions in prion science have remained unanswered.
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Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, University Hospital of Zürich, Schmelzbergstr. 12, CH-8091 Zürich, Switzerland.
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12
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Abstract
For more than two decades it has been contended that prion infection does not elicit immune responses: transmissible spongiform encephalopathies do not go along with conspicuous inflammatory infiltrates, and antibodies to the prion protein are typically undetectable. Why is it, then, that prions accumulate in lymphoid organs, and that various states of immune deficiency prevent peripheral prion infection? This review revisits the current evidence of the involvement of the immune system in prion diseases, while attempting to trace the elaborate mechanisms by which peripherally administered prions invade the brain and ultimately cause damage. The investigation of these questions leads to unexpected detours, including the neurophysiology of lymphoid organs, and even the function of a prion protein homolog in male fertility.
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Affiliation(s)
- Adriano Aguzzi
- Institute of Neuropathology, Universitätsspital Zürich, Schmelzbergstrasse 12, CH-8091 Zürich, Switzerland.
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13
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Aguzzi A, Brandner S, Fischer MB, Furukawa H, Glatzel M, Hawkins C, Heppner FL, Montrasio F, Navarro B, Parizek P, Pekarik V, Prinz M, Raeber AJ, Röckl C, Klein MA. Spongiform encephalopathies: insights from transgenic models. Adv Virus Res 2002; 56:313-52. [PMID: 11450305 DOI: 10.1016/s0065-3527(01)56032-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- A Aguzzi
- Institute of Neuropathology, Department of Pathology, Schmelzbergstrasse 12, University Hospital, 8091 Zurich, Switzerland
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14
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Abstract
Transmissible spongiform encephalopathies (TSEs), or prion diseases, are rare fatal neurodegenerative diseases of humans and animals. Although some TSEs, like scrapie in sheep, have been known to exist for centuries, bovine spongiform encephalopathy (BSE) was recognized only 15 years ago. New variant Creutzfeldt-Jakob disease (nvCJD) of humans is probably caused by consumption of BSE-infected materials. The nature of the infectious agent is not fully elucidated, but substantial evidence suggests that it is devoid of nucleic acids and consists at least in part of an abnormal form of a host protein termed PrP(C). Despite their rarity, prion diseases have become an important topic in public health and basic research because of the connection between nvCJD and BSE and also because of the unusual biological attributes of the infectious agent.
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Affiliation(s)
- M Glatzel
- Department of Pathology, Institute of Neuropathology, Schmelzbergstrasse 12, University Hospital Zurich, CH-8091, Zurich, Switzerland
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15
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Aguzzi A, Glatzel M, Montrasio F, Prinz M, Heppner FL. Interventional strategies against prion diseases. Nat Rev Neurosci 2001; 2:745-9. [PMID: 11584312 DOI: 10.1038/35094590] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Only a few years ago, the idea that transmissible spongiform encephalopathies could be treated pharmacologically would have met with considerable scepticism. Even now, there is no way to cure a patient or animal suffering from a manifest prion disease. But recent, exciting developments seem to indicate that immunological and pharmacological interventions could have some potential for the pre-exposure and post-exposure prophylaxis of prion diseases. Although it is unlikely that we will be able to cure the clinically overt stages of prion diseases in the foreseeable future, palliative and even life-prolonging interventions might no longer be confined to the realm of science fiction.
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16
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Heppner FL, Prinz M, Aguzzi A. Pathogenesis of prion diseases: possible implications of microglial cells. PROGRESS IN BRAIN RESEARCH 2001; 132:737-50. [PMID: 11545032 DOI: 10.1016/s0079-6123(01)32114-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- F L Heppner
- Institute of Neuropathology, Department of Pathology, University Hospital Zurich, Schmelzbergstrasse 12, CH-8091 Zurich, Switzerland
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17
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Brewer MS. Bovine spongiform encephalopathy--food safety implications. ADVANCES IN FOOD AND NUTRITION RESEARCH 2001; 43:265-317. [PMID: 11285685 DOI: 10.1016/s1043-4526(01)43007-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- M S Brewer
- Department of Food Science and Human Nutrition, University of Illinois, Urbana, Illinois, USA
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18
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Creutzfeldt-Jakob Disease (CJD) in a Case of Suspected Chronic Heavy Metal Poisoning. J Forensic Sci 2001. [DOI: 10.1520/jfs15026j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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19
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Aguzzi A. Recent developments in the pathogenesis, diagnosis, and therapy of prion diseases. DIALOGUES IN CLINICAL NEUROSCIENCE 2001. [PMID: 22034459 PMCID: PMC3181643 DOI: 10.31887/dcns.2001.3.1/aaguzzi] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Prions continue to pose a formidable challenge to life sciences. While human prion diseases are still rare, the incidence of a new variant of Creutzfeldt-Jakob disease in the United Kingdom is increasing exponentially - raising fears that it might develop into a major epidemic. This disease is likely to represent the result of human infection with bovine prions. Therefore, understanding how prions replicate and damage the brain, and how their action may be possibly counteracted, has become a major public health issue. Here I examine some current hypotheses concerning the links between bovine and human prion diseases, and the mechanisms by which prions reach and damage the central nervous system after having entered the body at extracerebral sites.
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20
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Aguzzi A, Klein MA, Montrasio F, Pekarik V, Brandner S, Furukawa H, Käser P, Röckl C, Glatzel M. Prions: pathogenesis and reverse genetics. Ann N Y Acad Sci 2001; 920:140-57. [PMID: 11193143 DOI: 10.1111/j.1749-6632.2000.tb06916.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Spongiform encephalopathies are a group of infectious neurodegenerative diseases. The infectious agent that causes transmissible spongiform encephalopathies was termed prion by Stanley Prusiner. The prion hypothesis states that the partially protease-resistant and detergent-insoluble prion protein (PrPsc) is identical with the infectious agent, and lacks any detectable nucleic acids. Since the latter discovery, transgenic mice have contributed many important insights into the field of prion biology. The prion protein (PrPc) is encoded by the Prnp gene, and disruption of Prnp leads to resistance to infection by prions. Introduction of mutant PrPc genes into PrPc-deficient mice was used to investigate structure-activity relationships of the PrPc gene with regard to scrapie susceptibility. Ectopic expression of PrPc in PrPc knockout mice proved a useful tool for the identification of host cells competent for prion replication. Finally, the availability of PrPc knockout and transgenic mice overexpressing PrPc allowed selective reconstitution experiments aimed at expressing PrPc in neurografts or in specific populations of hemato- and lymphopoietic cells. The latter studies helped in elucidating some of the mechanisms of prion spread and disease pathogenesis.
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Affiliation(s)
- A Aguzzi
- Institute of Neuropathology, University Hospital Zurich, CH-8091 Zurich, Switzerland.
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21
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Abstract
Although human prion diseases are rare, the incidence of 'new variant' Creutzfeldt-Jakob disease in the United Kingdom is increasing exponentially. Given that this disease is probably the result of infection with bovine prions, understanding how prions replicate--and how to counteract their action--has become a central issue for public health. What are the links between the bovine and human prion diseases, and how do prions reach and damage the central nervous system?
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Affiliation(s)
- A Aguzzi
- Institute of Neuropathology, University of Zurich, Schmelzbergstrasse 12, CH-8091 Zurich, Switzerland.
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22
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Abstract
Almost 20 years have passed since Stanley Prusiner proposed that the agent causing transmissible spongiform encephalopathies consists exclusively of a protein and termed it prion. A mixed balance can be drawn from the enormous research efforts that have gone into prion research during this time. On the negative side, the protein-only hypothesis has not been conclusively proven yet. On the positive side, our understanding of spongiform encephalopathies has experienced tremendous advances, mostly through human genetics, mouse transgenetics, and biophysical methods. Perhaps the most astonishing development is the realization that many human neurodegenerative diseases for which transmissibility has been more or less stringently excluded, may follow pathogenetic principles similar to those of prion diseases. Also, the hypothesis that prion-like phenomena may underlie certain non-genetic traits observed in yeast has resulted in the surprising recognition that the instructional self-propagating changes in protein conformation may be much more prevalent in nature than previously thought. The latter developments have been astonishingly successful, and one could now argue that the prion principle is much more solidly established in yeast than in mammals.
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Affiliation(s)
- A Aguzzi
- Institute of Neuropathology, Department of Pathology, Schmelzbergstrasse. 12, University Hospital Zurich, CH-8091 Zurich, Switzerland.
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23
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Porcher E, Gatto M. Quantifying the dynamics of prion infection: a bifurcation analysis of Laurent's model. J Theor Biol 2000; 205:283-96. [PMID: 10873439 DOI: 10.1006/jtbi.2000.2068] [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: 11/22/2022]
Abstract
Laurent (1996a, Médecine/sciences12, 774-785; 1996b, Biochem. J.318, 35-39; 1998, Bio-phys. Chem.72, 211-222) proposed a model for the dynamics of diseases of the central nervous system caused by prions. It is based on the protein-only hypothesis (Prusiner et al., 1981, Proc. Natl. Acad. Sci. U.S.A.78, 6675-6679), which assumes that infection can be spread by particular proteins (prions) that can exist in two forms that share the same sequence, but have a different structure. The normal form is harmless, while the infectious isoform of the prion protein catalyses a transconformation from the native isoform to itself within a specialized compartment of the brain cells. This paper systematically explores the model behavior with the aim of quantifying the fundamental parameters characterizing the dynamics of prion infection. To this end we use data from the literature to fix orders of magnitude for the rates of synthesis and degradation of the native form of prion protein and for the shape of the autocatalytic function. The dynamical behavior is classified with respect to two unknown parameters (bifurcation analysis): the rate of spontaneous transconformation and the rate of output of the infectious isoform from the specialized compartment. We thus find that the bistability properties evidenced by Laurent are confined to a certain range of parameters and that permanent oscillations of the two isoforms concentrations are possible. The bifurcation analysis allows us to estimate approximate ranges for the values of the two unknown parameters and consequently to derive incubation times and compare them with actual data for hamster. Also, our study predicts that the output rate of the infectious isoform is relatively insensitive to variations of model parameters.
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Affiliation(s)
- E Porcher
- Laboratoire Ecologie, Systématique et Evolution, Université Paris-Sud, Bâtiment 362, Orsay Cedex, 91405, France
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24
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Leist M, Nicotera P. Apoptosis versus necrosis: the shape of neuronal cell death. Results Probl Cell Differ 1999; 24:105-35. [PMID: 9949834 DOI: 10.1007/978-3-540-69185-3_6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- M Leist
- Faculty of Biology, University of Konstanz, Germany
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25
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Abstract
Although prions are most efficiently propagated via intracerebral inoculation, peripheral administration has caused kuru [Gajdusek et al, 1966], iatrogenic Creutzfeldt-Jakob disease (CJD) [Gibbs et al, 1997], bovine spongiform encephalitis (BSE), and new variant CJD [Hill et al, 1997; Bruce et al, 1997]. Neurological disease after peripheral inoculation depends on prion expansion within cells of the lymphoreticular system (LRS) [Lasmezas et al. 1996; Wilesmith et al, 1992]. In order to identify the nature of the latter cells, we inoculated a panel of immune deficient mice with prions intraperitoneally. While defects affecting only T lymphocytes had no apparent effect, all mutations affecting differentiation and responses of B lymphocytes prevented development of clinical scrapie. Since absence of B cells and of antibodies correlates with severe defects in follicular dendritic cells (FDCs), the lack of any of these three components may prevent clinical scrapie. Yet, mice expressing immunoglobulins exclusively of the M subclass without detectable specificity for PrPc, and mice with differentiated B cells but lacking functional FDCs, developed scrapie after peripheral inoculation: therefore, differentiated B cells appear to play a crucial role in neuroinvasion of scrapie regardless of B-cell receptor specificity.
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Affiliation(s)
- S Brandner
- Institute of Neuropathology, University of Zurich, Switzerland
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26
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Affiliation(s)
- A Aguzzi
- Institute of Neuropathology, University Hospital of Zurich, Department of Pathology, Schmelzbergstrasse 12, CH-8091 Zurich, Switzerland
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27
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Affiliation(s)
- P van der Valk
- Department of (Neuro)pathology, Free University Hospital, Amsterdam, The Netherlands
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28
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Turner JZ. I don't want to see the pictures: science writing and the visibility of animal experiments. PUBLIC UNDERSTANDING OF SCIENCE (BRISTOL, ENGLAND) 1998; 7:27-40. [PMID: 11657070 DOI: 10.1177/096366259800700103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The use of animals in research and development is one of the areas of science (human reproductive research and technology is perhaps another) where the fact that current practices are sanctioned in legislation does not prevent them from being controversial. This article examines the visibility of this issue in terms of the way science writers and scientific research papers report research that involves animals. Three journals with a scientific readership ( Nature, Science, and New Scientist) and two journals with a mixed scientist/nonscientist readership ( The Economist and The Times Higher Education Supplement) were examined. I have looked at the frequency of reports, the amount of experimental detail given, and the use of language, illustrations, and humor. Common features of these reports are the paucity of detail about the procedures carried out on the animals, their welfare and living conditions, and the numbers of animals used. However, there are significant differences between the journals with a “scientist” readership and those with a “mixed” readership in their readiness to debate the moral issue involved in human uses of animals. From these data the conclusion can be drawn that public debate might be improved by increasing the visibility of the animals themselves in reports of research involving their use.
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29
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Neurotoxicity and Neuroinvasiveness of Prions. Brain Pathol 1997. [DOI: 10.1111/j.1750-3639.1997.tb00994.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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30
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Affiliation(s)
- J Balter-Seri
- Department of Pediatrics, Schneider Children's Medical Center of Israel, Petah Tiqva, Israel
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Institute of Food Science & Technology (UK). BSE--bovine spongiform encephalopathy ('mad cow disease'). JOURNAL OF THE ROYAL SOCIETY OF HEALTH 1996; 116:322-333. [PMID: 8936952 DOI: 10.1177/146642409611600512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The issue of Bovine Spongiform Encephalopathy (BSE) is one of great concern to all members of the Society and we have had many requests for clarification of the scientific issues involved. Conflicting and disturbing claims and statements have been made in the press, confusing the issue. The definitive distillation of what is currently known is contained in the Position Statements produced by the Institute of Food Science & Technology (UK) and they have kindly allowed us to reproduce the most recent one below.
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