40 results on '"Lasmézas CI"'
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2. Une première étape dans l'identification de récepteurs cellulaires de la protéine du prion.
- Author
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Lasmézas, CI, primary, Deslys, JP, additional, Dormont, D, additional, and Weiss, S, additional
- Published
- 1998
- Full Text
- View/download PDF
3. New variant Creutzfeldt-Jakob disease in France
- Author
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Deslys, JP, primary, Lasmézas, CI, additional, Strechenbeiger, N, additional, Hill, A, additional, Collinge, J, additional, Dormont, D, additional, and Kopp, N, additional
- Published
- 1997
- Full Text
- View/download PDF
4. Hypothèses sur les mécanismes d'action de l'amphotéricine B et de ses dérivés dans les encéphalopathies subaiguës spongiformes transmissibles
- Author
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Adjou, K, primary, Deslys, JP, additional, Lasmézas, CI, additional, Demaimay, R, additional, Dormont, D, additional, and Seman, M, additional
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- 1997
- Full Text
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5. Novel methods for disinfection of prion-contaminated medical devices.
- Author
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Fichet G, Comoy E, Duval C, Antloga K, Dehen C, Charbonnier A, McDonnell G, Brown P, Lasmézas CI, and Deslys J
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- 2004
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6. Pα-syn* mitotoxicity is linked to MAPK activation and involves tau phosphorylation and aggregation at the mitochondria.
- Author
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Grassi D, Diaz-Perez N, Volpicelli-Daley LA, and Lasmézas CI
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- Aged, Aged, 80 and over, Animals, Enzyme Activation physiology, Female, Humans, Male, Mice, Mice, Inbred C57BL, Mitochondria pathology, Neurodegenerative Diseases pathology, Neurodegenerative Diseases physiopathology, Phosphorylation, Extracellular Signal-Regulated MAP Kinases metabolism, Mitochondria metabolism, Neurodegenerative Diseases metabolism, alpha-Synuclein metabolism, tau Proteins metabolism
- Abstract
We recently identified a truncated and phosphorylated form of α-synuclein, pα-syn*, as a key neurotoxic α-synuclein species found in cultured neurons, as well as in mouse and Parkinson's disease patients' brains. Small pα-syn* aggregates localize to mitochondria and induce mitochondrial damage and fragmentation. Herein, we investigated the molecular basis of pα-syn*-induced toxicity. By immunofluorescence, we found phosphorylated MKK4, JNK, ERK5 and p38 MAPKs in pα-syn* inclusions. pJNK colocalized with pα-syn* at mitochondria and mitochondria-associated ER membranes where it was associated with BiP and pACC1, markers for the ER and energy deprivation, respectively. We also found that pα-syn* aggregates are tightly associated with small ptau aggregates of similar size. Pα-syn*/ptau inclusions localized to areas of mitochondrial damage and to mitophagic vesicles, showing their role in mitochondrial toxicity, mitophagy induction and their removal along with damaged mitochondrial fragments. Several MAPKs may act cooperatively to phosphorylate tau, notably JNK, p38 and GSK3β, a non-MAPK that was also found phosphorylated in the vicinity of pα-syn*/ptau aggregates. These results add insight into the mechanisms by which pα-syn* exerts its toxic effects that include the phosphorylation of several kinases of the MAPK pathway, as well as the formation of ptau at the mitochondrial membrane, likely contributing to mitotoxicity. Thus pα-syn* appears to be the trigger of a series of kinase mediated pathogenic events and a link between α-syn pathology and tau, another protein known to aggregate in Parkinson's disease and other synucleinopathies., (Copyright © 2018. Published by Elsevier Inc.)
- Published
- 2019
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7. Identification of a highly neurotoxic α-synuclein species inducing mitochondrial damage and mitophagy in Parkinson's disease.
- Author
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Grassi D, Howard S, Zhou M, Diaz-Perez N, Urban NT, Guerrero-Given D, Kamasawa N, Volpicelli-Daley LA, LoGrasso P, and Lasmézas CI
- Subjects
- Acetyl-CoA Carboxylase chemistry, Acetyl-CoA Carboxylase metabolism, Animals, Brain drug effects, Brain pathology, Brain Chemistry, Cell Culture Techniques, Cells, Cultured, Humans, Lysosomes metabolism, Mice, Mitochondria, Oxidative Stress drug effects, Phosphorylation, Autophagy drug effects, Mitophagy drug effects, Neurotoxins chemistry, Neurotoxins metabolism, Neurotoxins toxicity, Parkinson Disease metabolism, alpha-Synuclein chemistry, alpha-Synuclein metabolism, alpha-Synuclein toxicity
- Abstract
Exposure of cultured primary neurons to preformed α-synuclein fibrils (PFFs) leads to the recruitment of endogenous α-synuclein and its templated conversion into fibrillar phosphorylated α-synuclein (pα-synF) aggregates resembling those involved in Parkinson's disease (PD) pathogenesis. Pα-synF was described previously as inclusions morphologically similar to Lewy bodies and Lewy neurites in PD patients. We discovered the existence of a conformationally distinct, nonfibrillar, phosphorylated α-syn species that we named "pα-syn*." We uniquely describe the existence of pα-syn* in PFF-seeded primary neurons, mice brains, and PD patients' brains. Through immunofluorescence and pharmacological manipulation we showed that pα-syn* results from incomplete autophagic degradation of pα-synF. Pα-synF was decorated with autophagic markers, but pα-syn* was not. Western blots revealed that pα-syn* was N- and C-terminally trimmed, resulting in a 12.5-kDa fragment and a SDS-resistant dimer. After lysosomal release, pα-syn* aggregates associated with mitochondria, inducing mitochondrial membrane depolarization, cytochrome C release, and mitochondrial fragmentation visualized by confocal and stimulated emission depletion nanoscopy. Pα-syn* recruited phosphorylated acetyl-CoA carboxylase 1 (ACC1) with which it remarkably colocalized. ACC1 phosphorylation indicates low ATP levels, AMPK activation, and oxidative stress and induces mitochondrial fragmentation via reduced lipoylation. Pα-syn* also colocalized with BiP, a master regulator of the unfolded protein response and a resident protein of mitochondria-associated endoplasmic reticulum membranes that are sites of mitochondrial fission and mitophagy. Pα-syn* aggregates were found in Parkin-positive mitophagic vacuoles and imaged by electron microscopy. Collectively, we showed that pα-syn* induces mitochondrial toxicity and fission, energetic stress, and mitophagy, implicating pα-syn* as a key neurotoxic α-syn species and a therapeutic target., Competing Interests: The authors declare no conflict of interest.
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- 2018
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8. Neuronal death induced by misfolded prion protein is due to NAD+ depletion and can be relieved in vitro and in vivo by NAD+ replenishment.
- Author
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Zhou M, Ottenberg G, Sferrazza GF, Hubbs C, Fallahi M, Rumbaugh G, Brantley AF, and Lasmézas CI
- Subjects
- Animals, Cell Death drug effects, Cells, Cultured, Female, Mice, Mice, Inbred C57BL, Neurons drug effects, Prion Diseases drug therapy, Prion Diseases metabolism, Prion Diseases pathology, NAD deficiency, NAD pharmacology, Neurons metabolism, Neurons pathology, Prions toxicity, Protein Folding drug effects
- Abstract
The mechanisms of neuronal death in protein misfolding neurodegenerative diseases such as Alzheimer's, Parkinson's and prion diseases are poorly understood. We used a highly toxic misfolded prion protein (TPrP) model to understand neurotoxicity induced by prion protein misfolding. We show that abnormal autophagy activation and neuronal demise is due to severe, neuron-specific, nicotinamide adenine dinucleotide (NAD(+)) depletion. Toxic prion protein-exposed neuronal cells exhibit dramatic reductions of intracellular NAD(+) followed by decreased ATP production, and are completely rescued by treatment with NAD(+) or its precursor nicotinamide because of restoration of physiological NAD(+) levels. Toxic prion protein-induced NAD(+) depletion results from PARP1-independent excessive protein ADP-ribosylations. In vivo, toxic prion protein-induced degeneration of hippocampal neurons is prevented dose-dependently by intracerebral injection of NAD(+). Intranasal NAD(+) treatment of prion-infected sick mice significantly improves activity and delays motor impairment. Our study reveals NAD(+) starvation as a novel mechanism of autophagy activation and neurodegeneration induced by a misfolded amyloidogenic protein. We propose the development of NAD(+) replenishment strategies for neuroprotection in prion diseases and possibly other protein misfolding neurodegenerative diseases., (© The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)
- Published
- 2015
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9. Unfolded protein response-induced ERdj3 secretion links ER stress to extracellular proteostasis.
- Author
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Genereux JC, Qu S, Zhou M, Ryno LM, Wang S, Shoulders MD, Kaufman RJ, Lasmézas CI, Kelly JW, and Wiseman RL
- Subjects
- Animals, CHO Cells, Cricetinae, Cricetulus, HSP40 Heat-Shock Proteins genetics, HeLa Cells, Hep G2 Cells, Humans, Prions genetics, Protein Aggregation, Pathological genetics, Protein Aggregation, Pathological pathology, Endoplasmic Reticulum Stress, HSP40 Heat-Shock Proteins metabolism, Prions metabolism, Protein Aggregates, Protein Aggregation, Pathological metabolism, Unfolded Protein Response
- Abstract
The Unfolded Protein Response (UPR) indirectly regulates extracellular proteostasis through transcriptional remodeling of endoplasmic reticulum (ER) proteostasis pathways. This remodeling attenuates secretion of misfolded, aggregation-prone proteins during ER stress. Through these activities, the UPR has a critical role in preventing the extracellular protein aggregation associated with numerous human diseases. Here, we demonstrate that UPR activation also directly influences extracellular proteostasis through the upregulation and secretion of the ER HSP40 ERdj3/DNAJB11. Secreted ERdj3 binds misfolded proteins in the extracellular space, substoichiometrically inhibits protein aggregation, and attenuates proteotoxicity of disease-associated toxic prion protein. Moreover, ERdj3 can co-secrete with destabilized, aggregation-prone proteins in a stable complex under conditions where ER chaperoning capacity is overwhelmed, preemptively providing extracellular chaperoning of proteotoxic misfolded proteins that evade ER quality control. This regulated co-secretion of ERdj3 with misfolded clients directly links ER and extracellular proteostasis during conditions of ER stress. ERdj3 is, to our knowledge, the first metazoan chaperone whose secretion into the extracellular space is regulated by the UPR, revealing a new mechanism by which UPR activation regulates extracellular proteostasis., (© 2014 The Authors.)
- Published
- 2015
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10. Unique drug screening approach for prion diseases identifies tacrolimus and astemizole as antiprion agents.
- Author
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Karapetyan YE, Sferrazza GF, Zhou M, Ottenberg G, Spicer T, Chase P, Fallahi M, Hodder P, Weissmann C, and Lasmézas CI
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- Animals, Astemizole therapeutic use, Blotting, Western, Cell Line, Tumor, Fluorescence Resonance Energy Transfer methods, High-Throughput Screening Assays methods, Humans, Kaplan-Meier Estimate, Mice, Mice, Inbred C57BL, Reverse Transcriptase Polymerase Chain Reaction, Astemizole pharmacology, Autophagy drug effects, Drug Discovery methods, Drug Evaluation, Preclinical methods, Prion Diseases drug therapy, Prions metabolism, Tacrolimus pharmacology
- Abstract
Prion diseases such as Creutzfeldt-Jakob disease (CJD) are incurable and rapidly fatal neurodegenerative diseases. Because prion protein (PrP) is necessary for prion replication but dispensable for the host, we developed the PrP-FRET-enabled high throughput assay (PrP-FEHTA) to screen for compounds that decrease PrP expression. We screened a collection of drugs approved for human use and identified astemizole and tacrolimus, which reduced cell-surface PrP and inhibited prion replication in neuroblastoma cells. Tacrolimus reduced total cellular PrP levels by a nontranscriptional mechanism. Astemizole stimulated autophagy, a hitherto unreported mode of action for this pharmacophore. Astemizole, but not tacrolimus, prolonged the survival time of prion-infected mice. Astemizole is used in humans to treat seasonal allergic rhinitis in a chronic setting. Given the absence of any treatment option for CJD patients and the favorable drug characteristics of astemizole, including its ability to cross the blood-brain barrier, it may be considered as therapy for CJD patients and for prophylactic use in familial prion diseases. Importantly, our results validate PrP-FEHTA as a method to identify antiprion compounds and, more generally, FEHTA as a unique drug discovery platform.
- Published
- 2013
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11. Strain-specific role of RNAs in prion replication.
- Author
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Saá P, Sferrazza GF, Ottenberg G, Oelschlegel AM, Dorsey K, and Lasmézas CI
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- Animals, Biological Assay methods, Brain metabolism, Immunohistochemistry methods, Mice, Mice, Inbred C57BL, Mice, Transgenic, Phenotype, Prion Diseases metabolism, Protein Folding, RNA genetics, Ribonuclease, Pancreatic metabolism, Scrapie metabolism, Species Specificity, Thermolysin chemistry, Gene Expression Regulation, Prions genetics, Prions metabolism, RNA metabolism
- Abstract
Several lines of evidence suggest that various cofactors may be required for prion replication. PrP binds to polyanions, and RNAs were shown to promote the conversion of PrP(C) into PrP(Sc) in vitro. In the present study, we investigated strain-specific differences in RNA requirement during in vitro conversion and the potential role of RNA as a strain-specifying component of infectious prions. We found that RNase treatment impairs PrP(Sc)-converting activity of 9 murine prion strains by protein misfolding cyclic amplification (PMCA) in a strain-specific fashion. While the addition of RNA restored PMCA conversion efficiency, the effect of synthetic polynucleotides or DNA was strain dependent, showing a different promiscuity of prion strains in cofactor utilization. The biological properties of RML propagated by PMCA under RNA-depleted conditions were compared to those of brain-derived and PMCA material generated in the presence of RNA. Inoculation of RNA-depleted RML in Tga20 mice resulted in an increased incidence of a distinctive disease phenotype characterized by forelimb paresis. However, this abnormal phenotype was not conserved in wild-type mice or upon secondary transmission. Immunohistochemical and cell panel assay analyses of mouse brains did not reveal significant differences between mice injected with the different RML inocula. We conclude that replication under RNA-depleted conditions did not modify RML prion strain properties. Our study cannot, however, exclude small variations of RML properties that would explain the abnormal clinical phenotype observed. We hypothesize that RNA molecules may act as catalysts of prion replication and that variable capacities of distinct prion strains to utilize different cofactors may explain strain-specific dependency upon RNA.
- Published
- 2012
- Full Text
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12. Highly neurotoxic monomeric α-helical prion protein.
- Author
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Zhou M, Ottenberg G, Sferrazza GF, and Lasmézas CI
- Subjects
- Animals, Apoptosis drug effects, Autophagy drug effects, Brain drug effects, Brain pathology, Cells, Cultured, Fibroblasts drug effects, Fibroblasts pathology, Mice, Neurons drug effects, Neurons pathology, Neurotoxins metabolism, Prion Diseases pathology, Prions metabolism, Protein Structure, Secondary, Neurotoxins chemistry, Neurotoxins toxicity, Prions chemistry, Prions toxicity
- Abstract
Prion diseases are infectious and belong to the group of protein misfolding neurodegenerative diseases. In these diseases, neuronal dysfunction and death are caused by the neuronal toxicity of a particular misfolded form of their cognate protein. The ability to specifically target the toxic protein conformer or the neuronal death pathway would provide powerful therapeutic approaches to these diseases. The neurotoxic forms of the prion protein (PrP) have yet to be defined but there is evidence suggesting that at least some of them differ from infectious PrP (PrP(Sc)). Herein, without making an assumption about size or conformation, we searched for toxic forms of recombinant PrP after dilution refolding, size fractionation, and systematic biological testing of all fractions. We found that the PrP species most neurotoxic in vitro and in vivo (toxic PrP, TPrP) is a monomeric, highly α-helical form of PrP. TPrP caused autophagy, apoptosis, and a molecular signature remarkably similar to that observed in the brains of prion-infected animals. Interestingly, highly α-helical intermediates have been described for other amyloidogenic proteins but their biological significance remains to be established. We provide unique experimental evidence that a monomeric α-helical form of an amyloidogenic protein represents a cytotoxic species. Although toxic PrP has yet to be purified from prion-infected brains, TPrP might be the equivalent of one highly neurotoxic PrP species generated during prion replication. Because TPrP is a misfolded, highly neurotoxic form of PrP reproducing several features of prion-induced neuronal death, it constitutes a useful model to study PrP-induced neurodegenerative mechanisms.
- Published
- 2012
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13. Prion strain discrimination based on rapid in vivo amplification and analysis by the cell panel assay.
- Author
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Karapetyan YE, Saá P, Mahal SP, Sferrazza GF, Sherman A, Salès N, Weissmann C, and Lasmézas CI
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- Animals, Brain metabolism, Brain pathology, Mice, Mice, Inbred C57BL, PrPC Proteins metabolism, PrPSc Proteins metabolism, Prions pathogenicity, Species Specificity, Biological Assay methods, Prions classification, Prions metabolism
- Abstract
Prion strain identification has been hitherto achieved using time-consuming incubation time determinations in one or more mouse lines and elaborate neuropathological assessment. In the present work, we make a detailed study of the properties of PrP-overproducing Tga20 mice. We show that in these mice the four prion strains examined are rapidly and faithfully amplified and can subsequently be discriminated by a cell-based procedure, the Cell Panel Assay.
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- 2009
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14. Atypical BSE (BASE) transmitted from asymptomatic aging cattle to a primate.
- Author
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Comoy EE, Casalone C, Lescoutra-Etchegaray N, Zanusso G, Freire S, Marcé D, Auvré F, Ruchoux MM, Ferrari S, Monaco S, Salès N, Caramelli M, Leboulch P, Brown P, Lasmézas CI, and Deslys JP
- Subjects
- Aging, Animals, Cattle growth & development, Creutzfeldt-Jakob Syndrome genetics, Creutzfeldt-Jakob Syndrome transmission, Encephalopathy, Bovine Spongiform genetics, Encephalopathy, Bovine Spongiform transmission, Frontal Lobe pathology, Genetic Predisposition to Disease, Humans, Species Specificity, Virulence, Cattle genetics, Macaca fascicularis genetics
- Abstract
Background: Human variant Creutzfeldt-Jakob Disease (vCJD) results from foodborne transmission of prions from slaughtered cattle with classical Bovine Spongiform Encephalopathy (cBSE). Atypical forms of BSE, which remain mostly asymptomatic in aging cattle, were recently identified at slaughterhouses throughout Europe and North America, raising a question about human susceptibility to these new prion strains., Methodology/principal Findings: Brain homogenates from cattle with classical BSE and atypical (BASE) infections were inoculated intracerebrally into cynomolgus monkeys (Macacca fascicularis), a non-human primate model previously demonstrated to be susceptible to the original strain of cBSE. The resulting diseases were compared in terms of clinical signs, histology and biochemistry of the abnormal prion protein (PrPres). The single monkey infected with BASE had a shorter survival, and a different clinical evolution, histopathology, and prion protein (PrPres) pattern than was observed for either classical BSE or vCJD-inoculated animals. Also, the biochemical signature of PrPres in the BASE-inoculated animal was found to have a higher proteinase K sensitivity of the octa-repeat region. We found the same biochemical signature in three of four human patients with sporadic CJD and an MM type 2 PrP genotype who lived in the same country as the infected bovine., Conclusion/significance: Our results point to a possibly higher degree of pathogenicity of BASE than classical BSE in primates and also raise a question about a possible link to one uncommon subset of cases of apparently sporadic CJD. Thus, despite the waning epidemic of classical BSE, the occurrence of atypical strains should temper the urge to relax measures currently in place to protect public health from accidental contamination by BSE-contaminated products.
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- 2008
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15. In vitro and in vivo neurotoxicity of prion protein oligomers.
- Author
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Simoneau S, Rezaei H, Salès N, Kaiser-Schulz G, Lefebvre-Roque M, Vidal C, Fournier JG, Comte J, Wopfner F, Grosclaude J, Schätzl H, and Lasmézas CI
- Subjects
- Animals, Antibodies, Blocking pharmacology, Antibodies, Monoclonal pharmacology, Apoptosis drug effects, Brain metabolism, Brain pathology, Cells, Cultured, Female, Intracellular Membranes drug effects, Mice, Mice, Inbred C57BL, Mice, Knockout, Neurons metabolism, Neurons pathology, Prion Diseases metabolism, Prion Diseases pathology, Prions chemistry, Prions immunology, Prions metabolism, Protein Isoforms, Protein Structure, Secondary, Brain drug effects, Neurons drug effects, Prion Diseases chemically induced, Prions toxicity
- Abstract
The mechanisms underlying prion-linked neurodegeneration remain to be elucidated, despite several recent advances in this field. Herein, we show that soluble, low molecular weight oligomers of the full-length prion protein (PrP), which possess characteristics of PrP to PrPsc conversion intermediates such as partial protease resistance, are neurotoxic in vitro on primary cultures of neurons and in vivo after subcortical stereotaxic injection. Monomeric PrP was not toxic. Insoluble, fibrillar forms of PrP exhibited no toxicity in vitro and were less toxic than their oligomeric counterparts in vivo. The toxicity was independent of PrP expression in the neurons both in vitro and in vivo for the PrP oligomers and in vivo for the PrP fibrils. Rescue experiments with antibodies showed that the exposure of the hydrophobic stretch of PrP at the oligomeric surface was necessary for toxicity. This study identifies toxic PrP species in vivo. It shows that PrP-induced neurodegeneration shares common mechanisms with other brain amyloidoses like Alzheimer disease and opens new avenues for neuroprotective intervention strategies of prion diseases targeting PrP oligomers.
- Published
- 2007
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16. Toxic effects of intracerebral PrP antibody administration during the course of BSE infection in mice.
- Author
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Lefebvre-Roque M, Kremmer E, Gilch S, Zou WQ, Féraudet C, Gilles CM, Salès N, Grassi J, Gambetti P, Baron T, Schätzl H, and Lasmézas CI
- Subjects
- Animals, Antibodies immunology, Antibodies therapeutic use, Antibody Formation immunology, Brain immunology, Cattle, Encephalopathy, Bovine Spongiform genetics, Encephalopathy, Bovine Spongiform immunology, Immunization, Passive methods, Immunoglobulin Fab Fragments immunology, Immunoglobulin Fab Fragments therapeutic use, Immunoglobulin G immunology, Immunoglobulin G therapeutic use, Mice, Mice, Transgenic, Prions immunology, Antibodies pharmacology, Encephalopathy, Bovine Spongiform drug therapy, Immunoglobulin Fab Fragments pharmacology, Immunoglobulin G pharmacology, Prions antagonists & inhibitors
- Abstract
The absence of specific immune response is a hallmark of prion diseases. However, in vitro and in vivo experiments have provided evidence that an anti-PrP humoral response could have beneficial effects. Prophylactic passive immunization performed at the time of infection delayed or prevented disease. Nonetheless, the potential therapeutic effect of PrP antibodies administered shortly before the clinical signs has never been tested in vivo. Moreover, a recent study showed the potential toxicity of PrP antibodies administered intracerebrally. We aimed at evaluating the effect of a prolonged intracerebral anti-PrP antibody administration at the time of neuroinvasion in BSE infected Tg20 mice. Unexpectedly, despite a good penetration of the antibodies in the brain parenchyma, the treatment was not protective against the development of BSE. Instead, it led to an extensive neuronal loss, strong astrogliosis and microglial activation. Since this effect was observed after injection of anti-PrP antibodies as whole IgGs, F(ab')(2) or Fab fragments, the toxicity was directly related to the ability of the antibodies to recognize native PrP and to the intracerebral concentration achieved, and not to the Fc portion or the divalence of the antibodies. This experiment shows that a prolonged treatment with anti-PrP antibodies by the intracerebral route can induce severe side-effects and calls for caution with regard to the use of similar approaches for late therapeutic interventions in humans.
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- 2007
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17. Of mice and men ... and vCJD.
- Author
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Lasmézas CI
- Subjects
- Animals, Carrier State, Creutzfeldt-Jakob Syndrome genetics, Disease Models, Animal, Genetic Predisposition to Disease, Genotype, Humans, Mice, Mice, Transgenic, Prions physiology, Creutzfeldt-Jakob Syndrome transmission
- Published
- 2006
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18. PrPTSE distribution in a primate model of variant, sporadic, and iatrogenic Creutzfeldt-Jakob disease.
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Herzog C, Rivière J, Lescoutra-Etchegaray N, Charbonnier A, Leblanc V, Salès N, Deslys JP, and Lasmézas CI
- Subjects
- Animals, Disease Models, Animal, Enzyme-Linked Immunosorbent Assay, Genetic Variation, Humans, Immunohistochemistry, Macaca fascicularis, Creutzfeldt-Jakob Syndrome pathology, Prions isolation & purification
- Abstract
Human prion diseases, such as Creutzfeldt-Jakob disease (CJD), are neurodegenerative and fatal. Sporadic CJD (sCJD) can be transmitted between humans through medical procedures involving highly infected organs, such as the central nervous system. However, in variant CJD (vCJD), which is due to human contamination with the bovine spongiform encephalopathy (BSE) agent, lymphoreticular tissue also harbors the transmissible spongiform encephalopathy-associated prion protein (PrP(TSE)), which poses a particularly acute risk for iatrogenic transmission. Two blood transfusion-related cases are already documented. In addition, the recent observation of PrP(TSE) in spleen and muscle in sCJD raised the possibility that peripheral PrP(TSE) is not limited to vCJD cases. We aimed to clarify the peripheral pathogenesis of human TSEs by using a nonhuman primate model which mimics human diseases. A highly sensitive enzyme-linked immunosorbent assay was adapted to the detection of extraneural PrP(TSE). We show that affected organs can be divided into two groups. The first is peripheral organs accumulating large amounts of PrP(TSE), which represent a high risk of iatrogenic transmission. This category comprises only lymphoreticular organs in the vCJD/BSE model. The second is organs with small amounts of PrP(TSE) associated with nervous structures. These are the muscles, adrenal glands, and enteric nervous system in the sporadic, iatrogenic, and variant CJD models. In contrast to the first set of organs, this low level of tissue contamination is not strain restricted and seems to be linked to secondary centrifugal spread of the agent through nerves. It might represent a risk for iatrogenic transmission, formerly underestimated despite previous reports of low rates of transmission from peripheral organs of humans to nonhuman primates (5, 10). This study provides an additional experimental basis for the classification of human organs into different risk categories and a rational re-evaluation of current risk management measures.
- Published
- 2005
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19. Risk of oral infection with bovine spongiform encephalopathy agent in primates.
- Author
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Lasmézas CI, Comoy E, Hawkins S, Herzog C, Mouthon F, Konold T, Auvré F, Correia E, Lescoutra-Etchegaray N, Salès N, Wells G, Brown P, and Deslys JP
- Subjects
- Animals, Brain pathology, Brain Chemistry, Cattle, Creutzfeldt-Jakob Syndrome transmission, Eating, Encephalopathy, Bovine Spongiform pathology, Macaca fascicularis, PrPSc Proteins analysis, Encephalopathy, Bovine Spongiform transmission, Food Contamination, Primate Diseases transmission
- Abstract
The uncertain extent of human exposure to bovine spongiform encephalopathy (BSE)--which can lead to variant Creutzfeldt-Jakob disease (vCJD)--is compounded by incomplete knowledge about the efficiency of oral infection and the magnitude of any bovine-to-human biological barrier to transmission. We therefore investigated oral transmission of BSE to non-human primates. We gave two macaques a 5 g oral dose of brain homogenate from a BSE-infected cow. One macaque developed vCJD-like neurological disease 60 months after exposure, whereas the other remained free of disease at 76 months. On the basis of these findings and data from other studies, we made a preliminary estimate of the food exposure risk for man, which provides additional assurance that existing public health measures can prevent transmission of BSE to man.
- Published
- 2005
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20. Knock-down of the 37-kDa/67-kDa laminin receptor in mouse brain by transgenic expression of specific antisense LRP RNA.
- Author
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Leucht C, Vana K, Renner-Müller I, Dormont D, Lasmézas CI, Wolf E, and Weiss S
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- Animals, Cell Line, Mice, Transgenic, Molecular Weight, Phosphopyruvate Hydratase genetics, Promoter Regions, Genetic, Rats, Receptors, Laminin genetics, Brain metabolism, Gene Expression, Mice genetics, RNA, Antisense metabolism, Receptors, Laminin metabolism
- Abstract
The 37-kDa/67-kDa laminin receptor (LRP/LR) plays a major role in the propagation of PrPSc, the abnormal form of the prion protein. In order to ablate the expression of LRP/LR in mouse brain we generated transgenic mice ectopically expressing antisense LRP RNA in the brain under control of the neuron-specific enolase (NSE) promoter. Hemizygous transgenic mice TgN(NSEasLRP)2 showed a significant reduction of LRP/LR protein levels in hippocampal and cerebellar brain regions. These mice might act as powerful tools to investigate the role of the laminin receptor in scrapie pathogenesis.
- Published
- 2004
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21. A novel generation of heparan sulfate mimetics for the treatment of prion diseases.
- Author
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Adjou KT, Simoneau S, Salès N, Lamoury F, Dormont D, Papy-Garcia D, Barritault D, Deslys JP, and Lasmézas CI
- Subjects
- Animals, Anti-Infective Agents chemical synthesis, Cattle, Cells, Cultured, Cricetinae, Disease Models, Animal, Disease Progression, Drug Design, Female, Heparitin Sulfate chemical synthesis, Injections, Intraperitoneal, Mice, Mice, Inbred C57BL, Molecular Structure, PrPC Proteins antagonists & inhibitors, Time Factors, Anti-Infective Agents pharmacology, Encephalopathy, Bovine Spongiform drug therapy, Heparitin Sulfate pharmacology, PrPSc Proteins antagonists & inhibitors, Scrapie drug therapy
- Abstract
The accumulation of PrP(res), the protease-resistant abnormal form of the host-encoded cellular prion protein, PrP(C), plays a central role in transmissible spongiform encephalopathies. Human contamination by bovine spongiform encephalopathy (BSE) has propelled many scientific teams on a highway for anti-prion drug development. This study reports that heparan sulfate mimetics (HMs), developed originally for their effect on tissue regeneration, abolish prion propagation in scrapie-infected GT1 cells. PrP(res) does not reappear for up to 50 days post-treatment. When tested in vivo, one of these compounds, HM2602, hampered PrP(res) accumulation in scrapie- and BSE-infected mice and prolonged significantly the survival time of 263K scrapie-infected hamsters. Interestingly, HM2602 is an apparently less toxic and more potent inhibitor of PrP(res) accumulation than dextran sulfate 500, a molecule known to exhibit anti-prion properties in vivo. Kinetics of PrP(res) disappearance in vitro and unaffected PrP(C) levels during treatment suggest that HMs are able to block the conversion of PrP(C) into PrP(res). It is speculated that HMs act as competitors of endogenous heparan sulfates known to act as co-receptors for the prion protein. Since these molecules are particularly amenable to drug design, their anti-prion potential could be developed further and optimized for the treatment of prion diseases.
- Published
- 2003
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22. The transmissible spongiform encephalopathies.
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Lasmézas CI
- Subjects
- Animals, Humans, Prion Diseases pathology, Prions chemistry, Prion Diseases etiology, Prions physiology
- Abstract
Transmissible spongiform encephalopathies (TSEs) represent a group of neurodegenerative diseases characterised by a very long incubation period in regard to the life expectancy of the host species. The lesions are restricted to the central nervous system, although the pathogenesis of infection implies a primary replication step of TSE agents in the lymphoid organs followed by a neuroinvasive phase. The outcome is always fatal and today there is neither cure nor prophylaxis for these diseases. For years, the causative agents of TSEs have posed a conundrum in terms of current knowledge of microorganisms, and there are still open questions about their exact nature. They are usually called TSE agents or prions because they are thoughtto be primarily composed of a modified host protein, the prion protein (PrP). A pathological form of the prion protein, called PrPSc (for scrapie) or PrPRes, an operational definition referring to resistance to proteolytic digestion, accumulates in target organs. The aim of this introductory chapter is to presentthe general features of TSEs and a modern understanding of TSE agents and their mode of replication. Notwithstanding the plethora of unsolved questions on these diseases and their aetiology, knowledge of their pathogenesis and recent advances in understanding of the molecular basis of PrP accumulation, together with detection systems, provide the tools to conduct sound TSE risk management.
- Published
- 2003
23. The 37 kDa/67 kDa laminin receptor is required for PrP(Sc) propagation in scrapie-infected neuronal cells.
- Author
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Leucht C, Simoneau S, Rey C, Vana K, Rieger R, Lasmézas CI, and Weiss S
- Subjects
- Animals, Biological Transport, Molecular Weight, Neuroblastoma, PrPSc Proteins genetics, RNA, Antisense pharmacology, RNA, Small Interfering pharmacology, Receptors, Laminin chemistry, Receptors, Laminin genetics, Receptors, Laminin immunology, Reverse Transcriptase Polymerase Chain Reaction, Ribonucleases, Scrapie genetics, Tumor Cells, Cultured, Neurons metabolism, PrPSc Proteins metabolism, Receptors, Laminin metabolism, Scrapie metabolism
- Abstract
The accumulation of PrP(Sc) in scrapie-infected neuronal cells has been prevented by three approaches: (i) transfection of ScMNB cells with an antisense laminin receptor precursor (LRP) RNA-expression plasmid, (ii) transfection of ScN2a cells and ScGT1 cells with small interfering RNAs (siRNAs) specific for the LRP mRNA, and (iii) incubation of ScN2a cells with an anti-LRP/LR antibody. LRP antisense RNA and LRP siRNAs reduced LRP/LR expression and inhibited the accumulation of PrP(Sc) in these cells. The treatments also reduced PrP(c) levels. The anti-LRP/LR antibody, W3, abolished PrP(Sc) accumulation and reduced PrP(c) levels after seven days of incubation. Cells remained free of PrP(Sc) after being cultured for 14 additional days without the antibody, whereas the PrP(c) level was restored. Our results demonstrate the necessity of the laminin receptor (LRP/LR) for PrP(Sc) propagation in cultured cells and suggest that LRP/LR-specific antibodies could be used as powerful therapeutic tools in the treatment of transmissible spongiform encephalopathies.
- Published
- 2003
- Full Text
- View/download PDF
24. Putative functions of PrP(C).
- Author
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Lasmézas CI
- Subjects
- Animals, Cell Differentiation, Cell Survival, Copper metabolism, Glycosaminoglycans metabolism, Heat-Shock Proteins metabolism, Heparitin Sulfate metabolism, Humans, PrPC Proteins metabolism, Protein Binding, Receptors, Cell Surface metabolism, Receptors, Laminin metabolism, Signal Transduction physiology, Cell Membrane metabolism, Neurons, Afferent metabolism, PrPC Proteins physiology
- Abstract
While the exact function of the cellular prion protein (PrP(C)) remains unknown, there are several leads due to increasing knowledge on the localisation and interaction of PrP(C) with other molecules. This chapter will concentrate on these aspects. Identified ligands of PrP(C) mainly belong to the categories of heat-shock proteins, membrane-bound receptors, or heparan sulphates. The possible synaptic role of PrP(C) has been exemplified by electrophysiological findings in PrP(o/o) mice and the studies of PrP(C) as a copper-binding molecule that could regulate the copper content of the synaptic cleft. The latter property of PrP(C) may also endow PrP(C) with the activity of a copper-dependent superoxide dismutase. Binding of PrP(C) to signalling molecules suggests a role as a transmitter of information from the extracellular milieu to the cell and a trigger for a molecular cascade. This agrees with new data on PrP(C) receptors and the role of PrP(C) in cell survival.
- Published
- 2003
- Full Text
- View/download PDF
25. The 37-kDa/67-kDa laminin receptor acts as the cell-surface receptor for the cellular prion protein.
- Author
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Gauczynski S, Peyrin JM, Haïk S, Leucht C, Hundt C, Rieger R, Krasemann S, Deslys JP, Dormont D, Lasmézas CI, and Weiss S
- Subjects
- Animals, Cell Line, Cell Membrane metabolism, Cricetinae, Flow Cytometry, Humans, Kidney cytology, Kidney metabolism, Mice, Mice, Knockout, Mutagenesis, Site-Directed, Neuroblastoma metabolism, Neurons cytology, Neurons metabolism, Oligopeptides, Peptides genetics, Prion Diseases etiology, Prions genetics, Protein Binding physiology, Protein Precursors genetics, Protein Structure, Tertiary physiology, Receptors, Laminin genetics, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins metabolism, Semliki forest virus genetics, Transfection, Prions metabolism, Protein Precursors metabolism, Receptors, Laminin metabolism
- Abstract
Recently, we identified the 37-kDa laminin receptor precursor (LRP) as an interactor for the prion protein (PrP). Here, we show the presence of the 37-kDa LRP and its mature 67-kDa form termed high-affinity laminin receptor (LR) in plasma membrane fractions of N2a cells, whereas only the 37-kDa LRP was detected in baby hamster kidney (BHK) cells. PrP co-localizes with LRP/LR on the surface of N2a cells and Semliki Forest virus (SFV) RNA transfected BHK cells. Cell-binding assays reveal the LRP/LR-dependent binding of cellular PrP by neuronal and non-neuronal cells. Hyperexpression of LRP on the surface of BHK cells results in the binding of exogenous PrP. Cell binding is similar in PrP(+/+) and PrP(0/0) primary neurons, demonstrating that PrP does not act as a co-receptor of LRP/LR. LRP/LR-dependent internalization of PrP is blocked at 4 degrees C. Secretion of an LRP mutant lacking the transmembrane domain (aa 86-101) from BHK cells abolishes PrP binding and internalization. Our results show that LRP/LR acts as the receptor for cellular PrP on the surface of mammalian cells.
- Published
- 2001
- Full Text
- View/download PDF
26. Identification of interaction domains of the prion protein with its 37-kDa/67-kDa laminin receptor.
- Author
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Hundt C, Peyrin JM, Haïk S, Gauczynski S, Leucht C, Rieger R, Riley ML, Deslys JP, Dormont D, Lasmézas CI, and Weiss S
- Subjects
- Animals, Binding Sites physiology, CHO Cells, Cell Line, Chromatography, Gel, Cricetinae, Galactosides metabolism, Glutathione Transferase genetics, Heparan Sulfate Proteoglycans genetics, Humans, Mice, Oligopeptides, Peptide Fragments genetics, Peptide Fragments metabolism, Peptides genetics, Prions genetics, Protein Binding physiology, Protein Precursors genetics, Protein Structure, Tertiary physiology, Receptors, Laminin genetics, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins metabolism, Semliki forest virus genetics, Heparan Sulfate Proteoglycans metabolism, Prions metabolism, Protein Precursors metabolism, Receptors, Laminin metabolism, Two-Hybrid System Techniques
- Abstract
Cell-binding and internalization studies on neuronal and non-neuronal cells have demonstrated that the 37-kDa/67-kDa laminin receptor (LRP/LR) acts as the receptor for the cellular prion protein (PrP). Here we identify direct and heparan sulfate proteoglycan (HSPG)-dependent interaction sites mediating the binding of the cellular PrP to its receptor, which we demonstrated in vitro on recombinant proteins. Mapping analyses in the yeast two-hybrid system and cell-binding assays identified PrPLRPbd1 [amino acids (aa) 144-179] as a direct and PrPLRPbd2 (aa 53-93) as an indirect HSPG-dependent laminin receptor precursor (LRP)-binding site on PrP. The yeast two-hybrid system localized the direct PrP-binding domain on LRP between aa 161 and 179. Expression of an LRP mutant lacking the direct PrP-binding domain in wild-type and mutant HSPG-deficient Chinese hamster ovary cells by the Semliki Forest virus system demonstrates a second HSPG-dependent PrP-binding site on LRP. Considering the absence of LRP homodimerization and the direct and indirect LRP-PrP interaction sites, we propose a comprehensive model for the LRP-PrP-HSPG complex.
- Published
- 2001
- Full Text
- View/download PDF
27. Adaptation of the bovine spongiform encephalopathy agent to primates and comparison with Creutzfeldt-- Jakob disease: implications for human health.
- Author
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Lasmézas CI, Fournier JG, Nouvel V, Boe H, Marcé D, Lamoury F, Kopp N, Hauw JJ, Ironside J, Bruce M, Dormont D, and Deslys JP
- Subjects
- Adaptation, Biological, Animals, Cattle, Creutzfeldt-Jakob Syndrome physiopathology, Disease Models, Animal, Encephalopathy, Bovine Spongiform physiopathology, Female, Humans, Immunohistochemistry, Mice, Mice, Inbred C57BL, Phenotype, Primate Diseases transmission, Primates, Scrapie physiopathology, Creutzfeldt-Jakob Syndrome transmission, Encephalopathy, Bovine Spongiform transmission, Prions analysis
- Abstract
There is substantial scientific evidence to support the notion that bovine spongiform encephalopathy (BSE) has contaminated human beings, causing variant Creutzfeldt-Jakob disease (vCJD). This disease has raised concerns about the possibility of an iatrogenic secondary transmission to humans, because the biological properties of the primate-adapted BSE agent are unknown. We show that (i) BSE can be transmitted from primate to primate by intravenous route in 25 months, and (ii) an iatrogenic transmission of vCJD to humans could be readily recognized pathologically, whether it occurs by the central or peripheral route. Strain typing in mice demonstrates that the BSE agent adapts to macaques in the same way as it does to humans and confirms that the BSE agent is responsible for vCJD not only in the United Kingdom but also in France. The agent responsible for French iatrogenic growth hormone-linked CJD taken as a control is very different from vCJD but is similar to that found in one case of sporadic CJD and one sheep scrapie isolate. These data will be key in identifying the origin of human cases of prion disease, including accidental vCJD transmission, and could provide bases for vCJD risk assessment.
- Published
- 2001
- Full Text
- View/download PDF
28. Diagnosis of bovine spongiform encephalopathy.
- Author
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Deslys JP, Lasmézas CI, Comoy E, and Domont D
- Subjects
- Animals, Cattle, Encephalopathy, Bovine Spongiform transmission, Humans, Mice, Zoonoses transmission, Encephalopathy, Bovine Spongiform diagnosis, Zoonoses virology
- Published
- 2001
- Full Text
- View/download PDF
29. Role of spleen macrophages in the clearance of scrapie agent early in pathogenesis.
- Author
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Beringue V, Demoy M, Lasmézas CI, Gouritin B, Weingarten C, Deslys JP, Andreux JP, Couvreur P, and Dormont D
- Subjects
- Analgesics, Non-Narcotic pharmacology, Animals, B-Lymphocytes drug effects, B-Lymphocytes immunology, Clodronic Acid pharmacology, Macrophages drug effects, Mice, Prions metabolism, Scrapie virology, T-Lymphocytes drug effects, T-Lymphocytes immunology, Macrophages immunology, Scrapie immunology, Spleen immunology
- Abstract
The involvement of spleen macrophages in the early stages of scrapie pathogenesis was studied by applying the 'macrophage-suicide technique' to scrapie-infected mice. This method comprises critically the intravenous administration to mice of dichloromethylene disphosphonate encapsulated into liposomes. Depletion of spleen macrophages before scrapie infection induced an increased amount of scrapie inoculum in the spleen, consequently leading to accelerated scrapie agent replication in the early phase of pathogenesis, as followed by PrPres accumulation, a specific hallmark of scrapie. The same effect was observed when spleen macrophages were depleted just before the beginning of scrapie agent replication. These findings suggest that macrophages may partly control scrapie infection in peripheral tissues by sequestration of the scrapie inoculum and may thus impair early scrapie agent replication in the spleen. In addition to macrophages, most follicular dendritic cells and B lymphocytes, which are thought to support scrapie agent replication, were also transiently depleted by dichloromethylene disphosphonate administration. This suggests that a compensatory mechanism is sufficient to ensure the persistence of infection in these early stages of pathogenesis., (Copyright 2000 John Wiley & Sons, Ltd.)
- Published
- 2000
- Full Text
- View/download PDF
30. Microglial cells respond to amyloidogenic PrP peptide by the production of inflammatory cytokines.
- Author
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Peyrin JM, Lasmézas CI, Haïk S, Tagliavini F, Salmona M, Williams A, Richie D, Deslys JP, and Dormont D
- Subjects
- Animals, Cells, Cultured, Electrophoresis, Polyacrylamide Gel, Humans, Inflammation metabolism, Interleukin-1 biosynthesis, Interleukin-6 biosynthesis, Lipopolysaccharides pharmacology, Mice, Mice, Inbred C57BL, Microglia drug effects, Nerve Degeneration pathology, RNA, Messenger biosynthesis, Reverse Transcriptase Polymerase Chain Reaction, Tumor Necrosis Factor-alpha biosynthesis, Cytokines biosynthesis, Microglia metabolism, Peptide Fragments pharmacology, Prions pharmacology
- Abstract
The scrapie isoform of the prion protein (PrPres) induces neurodegeneration and gliosis in the central nervous system. These features may be reproduced in vitro on exposure of neuronal and glial cultures to PrPres and the peptide HuPr P106-126. In the present study, we investigated the role of microglial cells and astrocytes in the pathological process by studying their molecular response to PrP 106-126 exposure. PrP 106-126 elicited a specific overproduction of pro-inflammatory cytokines IL1beta and IL6 in microglial cells (but not increased expression of TNFalpha, IL10, and TGFbeta1) and over-expression of GFAP in astrocytes. These effects were strictly dependent on the ability of the peptide to form amyloid fibrils. These data strongly suggest that microglial cells contribute to prion-related neurodegenerative processes by producing proinflammatory cytokines in the brain areas of amyloid PrP deposition.
- Published
- 1999
- Full Text
- View/download PDF
31. Role of the 37 kDa laminin receptor precursor in the life cycle of prions.
- Author
-
Rieger R, Lasmézas CI, and Weiss S
- Subjects
- Animals, Cattle, Evolution, Molecular, Humans, Mice, Mice, Knockout, Molecular Weight, Protein Conformation, Protein Precursors genetics, Receptors, Laminin genetics, Ribosomal Proteins genetics, Prions physiology, Protein Precursors physiology, Receptors, Laminin physiology, Ribosomal Proteins physiology
- Abstract
Prions are thought to consist of infectious proteins that cause, in the absence of detectable nucleic acid, a group of fatal neurodegenerative diseases, called transmissible spongiform encephalopathies (TSE). Among these diseases are bovine spongiform encephalopathy (BSE), scrapie of sheep and Creutzfeldt-Jakob disease (CJD) in humans. They occur as sporadic, infectious or genetic disorders and have in common the accumulation of an abnormal, pathogenic isoform of the cellular prion protein PrPc which is converted in a post-translational process into PrPSc concomitant with conformational changes of the protein. During this process PrPc acquires a high beta-sheet content and becomes partially resistant to proteases. The mechanism of this conversion as well as the physiological function of the cellular prion protein PrPc are poorly understood, but studies employing PrP knock-out mice demonstrated that PrPc is required for the development of prion diseases. The involvement of co-factors such as chaperones, receptors or an unknown protein, designated "protein X" in the conversion process are discussed. In a yeast two-hybrid screen we have identified the 37 kDa laminin receptor precursor (LRP) as an interactor of the cellular prion protein and this interaction could be confirmed by co-infection and co-transfection studies in mammalian and insect cells. LRP evolved from the ribosomal protein p40 essential for protein synthesis lacking any laminin binding activity to a cell surface receptor binding laminin, elastin and carbohydrates. The gene encoding 37 kDa LRP/p40 has been identified in a variety of species including the sea urchin Urechis caupo, Chlorohydra viridissima, the archaebacterium Haloarcula marismortui, the yeast Saccharomyces cerevisiae as well as in mammals where it is highly conserved. LRP works as a receptor for alphaviruses and is associated with the metastatic potential of solid tumors where it was first identified. The 37 kDa LRP forms its mature 67 kDa isoform with high laminin binding capacity by an unknown mechanism involving acylation. The multifunctionality of LRP as a ribosomal protein and a cell surface receptor for infectious agents such as viruses and prions might be extended by additional properties.
- Published
- 1999
- Full Text
- View/download PDF
32. Ultrastructural localization of cellular prion protein (PrPc) at the neuromuscular junction.
- Author
-
Gohel C, Grigoriev V, Escaig-Haye F, Lasmézas CI, Deslys JP, Langeveld J, Akaaboune M, Hantaï D, and Fournier JG
- Subjects
- Animals, Blotting, Western, Cricetinae, Fluorescent Antibody Technique, Indirect, Humans, Immunohistochemistry, Mesocricetus, Mice, Mice, Inbred C57BL, Microscopy, Confocal, Microscopy, Electron, Muscle, Skeletal metabolism, Muscle, Skeletal ultrastructure, Subcellular Fractions metabolism, Subcellular Fractions ultrastructure, Neuromuscular Junction metabolism, Neuromuscular Junction ultrastructure, Prions metabolism
- Abstract
We examined the localization of the normal cellular isoform of prion protein (PrPc) in mammalian skeletal muscle. Using two anti-PrP antibodies, the neuromuscular junction (NMJ) was preferentially stained after immunohistofluorescence. The mouse, hamster, and human NMJ displayed a fluorescent signal specific for PrPc. Postembedding immunoelectron microscopy analysis performed in the mouse muscle showed that the PrPc-specific colloidal gold immunolabelling was concentrated over the sarcoplasmic cytoplasm. The membrane of the postsynaptic domain was devoid of gold particles, while a weak signal was occasionally observed close to the presynaptic vesicles of the terminal axons. These results indicate that the PrP gene is expressed in mammalian muscle at the NMJ. The subsynaptic sarcoplasm of the NMJ appears to be the privileged site where PrPc presumably associated with endosome membrane may play a role in either physiological activity or maintenance of the morphological integrity of the synapse.
- Published
- 1999
- Full Text
- View/download PDF
33. Distribution and submicroscopic immunogold localization of cellular prion protein (PrPc) in extracerebral tissues.
- Author
-
Fournier JG, Escaig-Haye F, Billette de Villemeur T, Robain O, Lasmézas CI, Deslys JP, Dormont D, and Brown P
- Subjects
- Animals, Brain Chemistry, Cricetinae, Humans, Mesocricetus, Microscopy, Immunoelectron methods, Organ Specificity, Subcellular Fractions chemistry, Subcellular Fractions metabolism, Subcellular Fractions ultrastructure, Tissue Embedding, PrPC Proteins metabolism
- Abstract
In transmissible spongiform encephalopathies (TSE), such as scrapie in animals and Creutzfeldt-Jakob disease in humans, the central event is the conversion of a host-encoded amyloidogenic protein (PrPc) into an abnormal isoform (PrPsc) that accumulates as amyloid in TSE brain. PrPc is a membrane sialoglycoprotein synthesized in the central nervous system and elsewhere. We have examined the ultrastructural localization of PrPc in numerous hamster and some human extracerebral tissues, by means of a post-embedding electron-microscopic method combined with immunogold labeling. In stomach, intestine, lung, and kidney from hamsters, and in stomach, kidney, and spleen from humans, immunogold labeling specific for PrPc is observed on various cellular substructures related to secretory pathways: Golgi apparatus, secretory globules, and plasma membrane. In mucous epithelial cells of stomach and intestine, PrPc appears to be concentrated in secretory globules, suggesting a role for PrPc in the secretory function of the digestive tract. The secretory aspect of PrPc may be a key to understanding the physiopathological mechanisms underlying TSE.
- Published
- 1998
- Full Text
- View/download PDF
34. The human 37-kDa laminin receptor precursor interacts with the prion protein in eukaryotic cells.
- Author
-
Rieger R, Edenhofer F, Lasmézas CI, and Weiss S
- Subjects
- Actins metabolism, Animals, Binding Sites, COS Cells, Cell Line, Cricetinae, Eukaryotic Cells, Humans, Mice, Mice, Inbred C57BL, Protein Precursors chemistry, Protein Precursors genetics, Rabbits, Receptors, Laminin chemistry, Receptors, Laminin genetics, Recombinant Fusion Proteins chemistry, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins metabolism, Saccharomyces cerevisiae metabolism, Spodoptera cytology, PrPSc Proteins metabolism, Protein Precursors metabolism, Receptors, Laminin metabolism
- Abstract
Prions are thought to consist of infectious proteins that cause transmissible spongiform encephalopathies. According to overwhelming evidence, the pathogenic prion protein PrPSc converts its host encoded isoform PrPC into insoluble aggregates of PrPSc, concomitant with pathological modifications (for review, see refs. 1-3). Although the physiological role of PrPC is poorly understood, studies with PrP knockout mice demonstrated that PrPC is required for the development of prion diseases. Using the yeast two-hybrid technology in Saccharomyces cerevisiae, we identified the 37-kDa laminin receptor precursor (LRP) as interacting with the cellular prion protein PrPC. Mapping analysis of the LRP-PrP interaction site in S. cerevisiae revealed that PrP and laminin share the same binding domain (amino acids 161 to 180) on LRP. The LRP-PrP interaction was confirmed in vivo in insect (Sf9) and mammalian cells (COS-7). The LRP level was increased in scrapie-infected murine N2a cells and in brain and spleen of scrapie-infected mice. In contrast, the LRP concentration was not significantly altered in these organs from mice infected with the bovine spongiform encephalopathic agent (BSE), which have a lower PrPSc accumulation. LRP levels, however, were dramatically increased in brain and pancreas, slightly increased in the spleen and not altered in the liver of crapie-infected hamsters. These data show that enhanced LRP concentrations are correlated with PrPSc accumulation in organs from mice and hamsters. The laminin receptor precursor, which is highly conserved among mammals and is located on the cell surface, may act as a receptor or co-receptor for the prion protein on mammalian cells.
- Published
- 1997
- Full Text
- View/download PDF
35. Late treatment with polyene antibiotics can prolong the survival time of scrapie-infected animals.
- Author
-
Demaimay R, Adjou KT, Beringue V, Demart S, Lasmézas CI, Deslys JP, Seman M, and Dormont D
- Subjects
- Amino Acid Sequence, Amphotericin B pharmacology, Animals, Anti-Bacterial Agents pharmacology, Drug Administration Schedule, Female, Mice, Mice, Inbred C57BL, Molecular Sequence Data, PrPSc Proteins, Rabbits, Scrapie physiopathology, Time Factors, Amphotericin B analogs & derivatives, Polyenes pharmacology, Scrapie drug therapy
- Abstract
Amphotericin B (AmB) is one of the few drugs able to prolong survival times in experimental scrapie and delays the accumulation of PrPres, a specific marker of this disease in the brain in vivo. Previous reports showed that the AmB effect is observed only if the drug is administered around the time of infection. In the present study, intracerebrally infected mice were treated with AmB or one of its derivatives, MS-8209, between 80 and 140 days postinoculation. We observed an increased incubation time and a delay in PrPres accumulation and glial fibrillary acidic protein gene expression. Treatment starting at 80 days postinoculation was as efficient as long-term treatment starting the day of inoculation. Our results indicate that polyene antibiotics may interfere, throughout the course of the experimental disease, with the propagation of the scrapie agent.
- Published
- 1997
- Full Text
- View/download PDF
36. Transmission of the BSE agent to mice in the absence of detectable abnormal prion protein.
- Author
-
Lasmézas CI, Deslys JP, Robain O, Jaegly A, Beringue V, Peyrin JM, Fournier JG, Hauw JJ, Rossier J, and Dormont D
- Subjects
- Animals, Apoptosis, Astrocytes pathology, Brain pathology, Cattle, Encephalopathy, Bovine Spongiform metabolism, Encephalopathy, Bovine Spongiform pathology, Endopeptidases metabolism, Mice, Mice, Inbred C57BL, Phenotype, Purkinje Cells pathology, Serial Passage, Time Factors, Vacuoles pathology, Brain Chemistry, Encephalopathy, Bovine Spongiform transmission, Nerve Tissue Proteins analysis, Prions analysis
- Abstract
The agent responsible for transmissible spongiform encephalopathies (TSEs) is thought to be a malfolded, protease-resistant version (PrPres) of the normal cellular prion protein (PrP). The interspecies transmission of bovine spongiform encephalopathy (BSE) to mice was studied. Although all of the mice injected with homogenate from BSE-infected cattle brain exhibited neurological symptoms and neuronal death, more than 55 percent had no detectable PrPres. During serial passage, PrPres appeared after the agent became adapted to the new host. Thus, PrPres may be involved in species adaptation, but a further unidentified agent may actually transmit BSE.
- Published
- 1997
- Full Text
- View/download PDF
37. Strain specific and common pathogenic events in murine models of scrapie and bovine spongiform encephalopathy.
- Author
-
Lasmézas CI, Deslys JP, Demaimay R, Adjou KT, Hauw JJ, and Dormont D
- Subjects
- Animals, Astrocytes metabolism, Cattle, Disease Models, Animal, Encephalopathy, Bovine Spongiform pathology, Encephalopathy, Bovine Spongiform physiopathology, Glial Fibrillary Acidic Protein metabolism, Mice, Mice, Inbred C57BL, Scrapie pathology, Scrapie physiopathology, Sheep, Time Factors, Encephalopathy, Bovine Spongiform etiology, PrPSc Proteins pathogenicity, Scrapie etiology
- Abstract
The development of transmissible spongiform encephalopathies in experimental models depends on two major factors: the intracerebral accumulation of an abnormal, protease-resistant isoform of PrP (PrPres), which is a host protein mainly expressed in neurons; and the existence of different strains of agent. In order to make a distinction between pathogenic mechanisms depending upon the accumulation of host-derived PrPres and the strain-specific effects, we quantified and compared the sequence of molecular [PrPres and glial fibrillary acidic protein (GFAP) accumulation] and pathological events in the brains of syngeneic mice throughout the course of infection with two different strains of agent. The bovine spongiform encephalopathy (BSE) agent exhibits properties different from any known scrapie source and has been studied in comparison with a classical scrapie strain. Convergent kinetic data in both models confirmed the cause-effect relationship between PrPres and pathological changes and showed that PrPres accumulation is directly responsible for astrocyte activation in vivo. Moreover, we observed a threshold level of PrPres for this effect on astroglial cells. However, despite similar infectivity titres, the BSE model produced less PrPres than scrapie, and the relative importance of gliosis was higher. The comparison of the molecular and pathological features after intracerebral or intraperitoneal inoculation also revealed differences between the models. Therefore, the mechanisms leading to the targeting and the fine regulation of the molecular events seem to be independent of the host PrP and to depend upon the agent. The possible involvement of a regulatory molecule accounting for these specificities has to be considered.
- Published
- 1996
- Full Text
- View/download PDF
38. Differential effects of a new amphotericin B derivative, MS-8209, on mouse BSE and scrapie: implications for the mechanism of action of polyene antibiotics.
- Author
-
Adjou KT, Demaimay R, Lasmézas CI, Seman M, Deslys JP, and Dormont D
- Subjects
- Amphotericin B therapeutic use, Animals, Anti-Bacterial Agents, Cattle, Dose-Response Relationship, Drug, Female, Mice, Mice, Inbred C57BL, Polyenes, PrPSc Proteins metabolism, Amphotericin B analogs & derivatives, Antiviral Agents therapeutic use, Encephalopathy, Bovine Spongiform drug therapy, Scrapie drug therapy
- Abstract
Mice were infected intracerebrally with the bovine spongiform encephalopathy (BSE) or the scrapie agent and treated during 8 weeks postinfection to test the protective effect of a new amphotericin B (AmB) derivative, MS-8209, in experimental transmissible spongiform encephalopathies. The results show that (i) the treatment prolonged the incubation period of both BSE-infected and scrapie-infected mice, (ii) MS-8209 and AmB were much more efficient in delaying the onset of scrapie than that of BSE, and (iii) a delay in Prp-res (proteinase K-resistant prion protein) and GFAP (glial fibrillary acidic protein) accumulation was observed in the brains of scrapie-infected mice, but was not significant in BSE-infected mice. The analysis of the molecular and clinical results strongly suggests a common mechanism of action of this category of drugs on the different transmissible spongiform encephalopathy strains. This could be due to an interaction with the PrP transconformation process leading to the formation of PrP-res.
- Published
- 1996
- Full Text
- View/download PDF
39. BSE transmission to macaques.
- Author
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Lasmézas CI, Deslys JP, Demaimay R, Adjou KT, Lamoury F, Dormont D, Robain O, Ironside J, and Hauw JJ
- Subjects
- Animals, Brain pathology, Cattle, Creutzfeldt-Jakob Syndrome pathology, Encephalopathy, Bovine Spongiform pathology, Humans, Macaca, PrPSc Proteins metabolism, Prions genetics, Species Specificity, Creutzfeldt-Jakob Syndrome transmission, Encephalopathy, Bovine Spongiform transmission
- Published
- 1996
- Full Text
- View/download PDF
40. Immune system-dependent and -independent replication of the scrapie agent.
- Author
-
Lasmézas CI, Cesbron JY, Deslys JP, Demaimay R, Adjou KT, Rioux R, Lemaire C, Locht C, and Dormont D
- Subjects
- Animals, Brain immunology, Immune System, Mice, Mice, Inbred C57BL, Mice, SCID, PrPSc Proteins biosynthesis, Spleen immunology, PrPSc Proteins immunology, Scrapie immunology
- Abstract
Using the severe combined immunodeficiency (SCID) mouse model, we investigated the requirement of the immune system for the development of scrapie after peripheral inoculation. A total of 33% of SCID mice, all but one immunologically reconstituted SCID mice (93%), and all CB17 control mice developed the disease. PrPres was detectable in the brains of all diseased animals and in the spleens of reconstituted SCID and CB17 control mice but not of the diseased non-immunologically reconstituted SCID mice. The immune system appears to be a primary target in the pathogenesis of scrapie, but direct spread to the central nervous system from the peritoneum via visceral nerve fibers can probably also occur.
- Published
- 1996
- Full Text
- View/download PDF
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