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Sample records for sporadic human prion

  1. Molecular pathogenesis of sporadic prion diseases in man

    Science.gov (United States)

    Safar, Jiri G.

    2012-01-01

    The yeast, fungal and mammalian prions determine heritable and infectious traits that are encoded in alternative conformations of proteins. They cause lethal sporadic, familial and infectious neurodegenerative conditions in man, including Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), kuru, sporadic fatal insomnia (SFI) and likely variable protease-sensitive prionopathy (VPSPr). The most prevalent of human prion diseases is sporadic (s)CJD. Recent advances in amplification and detection of prions led to considerable optimism that early and possibly preclinical diagnosis and therapy might become a reality. Although several drugs have already been tested in small numbers of sCJD patients, there is no clear evidence of any agent’s efficacy. Therefore, it remains crucial to determine the full spectrum of sCJD prion strains and the conformational features in the pathogenic human prion protein governing replication of sCJD prions. Research in this direction is essential for the rational development of diagnostic as well as therapeutic strategies. Moreover, there is growing recognition that fundamental processes involved in human prion propagation – intercellular induction of protein misfolding and seeded aggregation of misfolded host proteins – are of far wider significance. This insight leads to new avenues of research in the ever-widening spectrum of age-related human neurodegenerative diseases that are caused by protein misfolding and that pose a major challenge for healthcare. PMID:22421210

  2. The Prion Protein Preference of Sporadic Creutzfeldt-Jakob Disease Subtypes*

    Science.gov (United States)

    Klemm, Helen M. J.; Welton, Jeremy M.; Masters, Colin L.; Klug, Genevieve M.; Boyd, Alison; Hill, Andrew F.; Collins, Steven J.; Lawson, Victoria A.

    2012-01-01

    Sporadic Creutzfeldt-Jakob disease (CJD) is the most prevalent manifestation of the transmissible spongiform encephalopathies or prion diseases affecting humans. The disease encompasses a spectrum of clinical phenotypes that have been correlated with molecular subtypes that are characterized by the molecular mass of the protease-resistant fragment of the disease-related conformation of the prion protein and a polymorphism at codon 129 of the gene encoding the prion protein. A cell-free assay of prion protein misfolding was used to investigate the ability of these sporadic CJD molecular subtypes to propagate using brain-derived sources of the cellular prion protein (PrPC). This study confirmed the presence of three distinct sporadic CJD molecular subtypes with PrPC substrate requirements that reflected their codon 129 associations in vivo. However, the ability of a sporadic CJD molecular subtype to use a specific PrPC substrate was not determined solely by codon 129 as the efficiency of prion propagation was also influenced by the composition of the brain tissue from which the PrPC substrate was sourced, thus indicating that nuances in PrPC or additional factors may determine sporadic CJD subtype. The results of this study will aid in the design of diagnostic assays that can detect prion disease across the diversity of sporadic CJD subtypes. PMID:22930754

  3. Prion-Seeding Activity Is widely Distributed in Tissues of Sporadic Creutzfeldt-Jakob Disease Patients

    Directory of Open Access Journals (Sweden)

    Hanae Takatsuki, PhD

    2016-10-01

    Full Text Available Human prion diseases are neurodegenerative disorders caused by abnormally folded prion proteins in the central nervous system. These proteins can be detected using the quaking-induced conversion assay. Compared with other bioassays, this assay is extremely sensitive and was used in the present study to determine prion distribution in sporadic Creutzfeldt-Jakob disease patients at autopsy. Although infectivity of the sporadic form is thought to be restricted within the central nervous system, results showed that prion-seeding activities reach 106/g from a 50% seeding dose in non-neuronal tissues, suggesting that prion-seeding activity exists in non-neural organs, and we suggested that non-neural tissues of 106/g SD50 did not exist the infectivity.

  4. Prion-Seeding Activity Is widely Distributed in Tissues of Sporadic Creutzfeldt-Jakob Disease Patients.

    Science.gov (United States)

    Takatsuki, Hanae; Fuse, Takayuki; Nakagaki, Takehiro; Mori, Tsuyoshi; Mihara, Ban; Takao, Masaki; Iwasaki, Yasushi; Yoshida, Mari; Murayama, Shigeo; Atarashi, Ryuichiro; Nishida, Noriyuki; Satoh, Katsuya

    2016-10-01

    Human prion diseases are neurodegenerative disorders caused by abnormally folded prion proteins in the central nervous system. These proteins can be detected using the quaking-induced conversion assay. Compared with other bioassays, this assay is extremely sensitive and was used in the present study to determine prion distribution in sporadic Creutzfeldt-Jakob disease patients at autopsy. Although infectivity of the sporadic form is thought to be restricted within the central nervous system, results showed that prion-seeding activities reach 10 6 /g from a 50% seeding dose in non-neuronal tissues, suggesting that prion-seeding activity exists in non-neural organs, and we suggested that non-neural tissues of 10 6 /g SD50 did not exist the infectivity. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  5. Glycoform-selective prion formation in sporadic and familial forms of prion disease

    NARCIS (Netherlands)

    Xiao, X.; Yuan, J.; Haïk, S.; Cali, I.; Zhan, Y.; Moudjou, M.; Li, B.; Laplanche, J.L.; Laude, H.; Langeveld, J.P.M.; Gambetti, P.

    2013-01-01

    The four glycoforms of the cellular prion protein (PrP(C)) variably glycosylated at the two N-linked glycosylation sites are converted into their pathological forms (PrP(Sc)) in most cases of sporadic prion diseases. However, a prominent molecular characteristic of PrP(Sc) in the recently identified

  6. Molecular Pathology of Human Prion Diseases

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available Prion diseases are fatal neurodegenerative conditions in humans and animals. In this review, we summarize the molecular background of phenotypic variability, relation of prion protein (PrP to other proteins associated with neurodegenerative diseases, and pathogenesis of neuronal vulnerability. PrP exists in different forms that may be present in both diseased and non-diseased brain, however, abundant disease-associated PrP together with tissue pathology characterizes prion diseases and associates with transmissibility. Prion diseases have different etiological background with distinct pathogenesis and phenotype. Mutations of the prion protein gene are associated with genetic forms. The codon 129 polymorphism in combination with the Western blot pattern of PrP after proteinase K digestion serves as a basis for molecular subtyping of sporadic Creutzfeldt-Jakob disease. Tissue damage may result from several parallel, interacting or subsequent pathways that involve cellular systems associated with synapses, protein processing, oxidative stress, autophagy, and apoptosis.

  7. Positive 14-3-3 and tau proteins in a sporadic Creutzfeldt-Jakob disease case and a brief perspective of prion diseases in Colombia.

    Science.gov (United States)

    Escandón-Vargas, Kevin; Zorrilla-Vaca, Andrés; Corral-Prado, Raúl Heli

    2016-02-24

    Prion diseases are rare neurodegenerative disorders occurring worldwide and affecting both humans and animals. Herein, we present the case of a patient diagnosed with definite sporadic Creutzfeldt-Jakob disease in Cali, Colombia. Besides neurological examination, 14-3-3 and tau proteins were valuable tools supporting the diagnosis. We also present a brief perspective of the prion diseases reported in Colombia to date. Although the incidence of prion diseases is unknown in Colombia, our literature review revealed that one case of scrapie in 1981 and 29 human sporadic cases of Creutzfeldt-Jakob disease have been documented and published in our country.

  8. The Distribution of Prion Protein Allotypes Differs Between Sporadic and Iatrogenic Creutzfeldt-Jakob Disease Patients.

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    Moore, Roger A; Head, Mark W; Ironside, James W; Ritchie, Diane L; Zanusso, Gianluigi; Choi, Young Pyo; Pyo Choi, Young; Priola, Suzette A

    2016-02-01

    Sporadic Creutzfeldt-Jakob disease (sCJD) is the most prevalent of the human prion diseases, which are fatal and transmissible neurodegenerative diseases caused by the infectious prion protein (PrP(Sc)). The origin of sCJD is unknown, although the initiating event is thought to be the stochastic misfolding of endogenous prion protein (PrP(C)) into infectious PrP(Sc). By contrast, human growth hormone-associated cases of iatrogenic CJD (iCJD) in the United Kingdom (UK) are associated with exposure to an exogenous source of PrP(Sc). In both forms of CJD, heterozygosity at residue 129 for methionine (M) or valine (V) in the prion protein gene may affect disease phenotype, onset and progression. However, the relative contribution of each PrP(C) allotype to PrP(Sc) in heterozygous cases of CJD is unknown. Using mass spectrometry, we determined that the relative abundance of PrP(Sc) with M or V at residue 129 in brain specimens from MV cases of sCJD was highly variable. This result is consistent with PrP(C) containing an M or V at residue 129 having a similar propensity to misfold into PrP(Sc) thus causing sCJD. By contrast, PrP(Sc) with V at residue 129 predominated in the majority of the UK human growth hormone associated iCJD cases, consistent with exposure to infectious PrP(Sc) containing V at residue 129. In both types of CJD, the PrP(Sc) allotype ratio had no correlation with CJD type, age at clinical onset, or disease duration. Therefore, factors other than PrP(Sc) allotype abundance must influence the clinical progression and phenotype of heterozygous cases of CJD.

  9. Glycoform-Selective Prion Formation in Sporadic and Familial Forms of Prion Disease

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    Xiao, Xiangzhu; Yuan, Jue; Haïk, Stéphane; Cali, Ignazio; Zhan, Yian; Moudjou, Mohammed; Li, Baiya; Laplanche, Jean-Louis; Laude, Hubert; Langeveld, Jan; Gambetti, Pierluigi; Kitamoto, Tetsuyuki; Kong, Qingzhong; Brandel, Jean-Philippe; Cobb, Brian A.; Petersen, Robert B.; Zou, Wen-Quan

    2013-01-01

    The four glycoforms of the cellular prion protein (PrPC) variably glycosylated at the two N-linked glycosylation sites are converted into their pathological forms (PrPSc) in most cases of sporadic prion diseases. However, a prominent molecular characteristic of PrPSc in the recently identified variably protease-sensitive prionopathy (VPSPr) is the absence of a diglycosylated form, also notable in familial Creutzfeldt-Jakob disease (fCJD), which is linked to mutations in PrP either from Val to Ile at residue 180 (fCJDV180I) or from Thr to Ala at residue 183 (fCJDT183A). Here we report that fCJDV180I, but not fCJDT183A, exhibits a proteinase K (PK)-resistant PrP (PrPres) that is markedly similar to that observed in VPSPr, which exhibits a five-step ladder-like electrophoretic profile, a molecular hallmark of VPSPr. Remarkably, the absence of the diglycosylated PrPres species in both fCJDV180I and VPSPr is likewise attributable to the absence of PrPres glycosylated at the first N-linked glycosylation site at residue 181, as in fCJDT183A. In contrast to fCJDT183A, both VPSPr and fCJDV180I exhibit glycosylation at residue 181 on di- and monoglycosylated (mono181) PrP prior to PK-treatment. Furthermore, PrPV180I with a typical glycoform profile from cultured cells generates detectable PrPres that also contains the diglycosylated PrP in addition to mono- and unglycosylated forms upon PK-treatment. Taken together, our current in vivo and in vitro studies indicate that sporadic VPSPr and familial CJDV180I share a unique glycoform-selective prion formation pathway in which the conversion of diglycosylated and mono181 PrPC to PrPSc is inhibited, probably by a dominant-negative effect, or by other co-factors. PMID:23527023

  10. Sporadic Creutzfeldt-Jakob Disease: Prion Pathology in Medulla Oblongata-Possible Routes of Infection and Host Susceptibility.

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    Iacono, Diego; Ferrari, Sergio; Gelati, Matteo; Zanusso, Gianluigi; Mariotto, Sara; Monaco, Salvatore

    2015-01-01

    Sporadic Creutzfeldt-Jakob disease (sCJD), the most frequent human prion disorder, is characterized by remarkable phenotypic variability, which is influenced by the conformation of the pathologic prion protein and the methionine/valine polymorphic codon 129 of the prion protein gene. While the etiology of sCJD remains unknown, it has been hypothesized that environmental exposure to prions might occur through conjunctival/mucosal contact, oral ingestion, inhalation, or simultaneous involvement of the olfactory and enteric systems. We studied 21 subjects with definite sCJD to assess neuropathological involvement of the dorsal motor nucleus of the vagus and other medullary nuclei and to evaluate possible associations with codon 129 genotype and prion protein conformation. The present data show that prion protein deposition was detected in medullary nuclei of distinct sCJD subtypes, either valine homozygous or heterozygous at codon 129. These findings suggest that an "environmental exposure" might occur, supporting the hypothesis that external sources of contamination could contribute to sCJD in susceptible hosts. Furthermore, these novel data could shed the light on possible causes of sCJD through a "triple match" hypothesis that identify environmental exposure, host genotype, and direct exposure of specific anatomical regions as possible pathogenetic factors.

  11. Human prion diseases: surgical lessons learned from iatrogenic prion transmission.

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    Bonda, David J; Manjila, Sunil; Mehndiratta, Prachi; Khan, Fahd; Miller, Benjamin R; Onwuzulike, Kaine; Puoti, Gianfranco; Cohen, Mark L; Schonberger, Lawrence B; Cali, Ignazio

    2016-07-01

    The human prion diseases, or transmissible spongiform encephalopathies, have captivated our imaginations since their discovery in the Fore linguistic group in Papua New Guinea in the 1950s. The mysterious and poorly understood "infectious protein" has become somewhat of a household name in many regions across the globe. From bovine spongiform encephalopathy (BSE), commonly identified as mad cow disease, to endocannibalism, media outlets have capitalized on these devastatingly fatal neurological conditions. Interestingly, since their discovery, there have been more than 492 incidents of iatrogenic transmission of prion diseases, largely resulting from prion-contaminated growth hormone and dura mater grafts. Although fewer than 9 cases of probable iatrogenic neurosurgical cases of Creutzfeldt-Jakob disease (CJD) have been reported worldwide, the likelihood of some missed cases and the potential for prion transmission by neurosurgery create considerable concern. Laboratory studies indicate that standard decontamination and sterilization procedures may be insufficient to completely remove infectivity from prion-contaminated instruments. In this unfortunate event, the instruments may transmit the prion disease to others. Much caution therefore should be taken in the absence of strong evidence against the presence of a prion disease in a neurosurgical patient. While the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) have devised risk assessment and decontamination protocols for the prevention of iatrogenic transmission of the prion diseases, incidents of possible exposure to prions have unfortunately occurred in the United States. In this article, the authors outline the historical discoveries that led from kuru to the identification and isolation of the pathological prion proteins in addition to providing a brief description of human prion diseases and iatrogenic forms of CJD, a brief history of prion disease nosocomial transmission

  12. Human prion diseases in The Netherlands : clinico-pathological, genetic and molecular aspects

    NARCIS (Netherlands)

    Jansen, C.

    2011-01-01

    Prion diseases, or transmissible spongiform encephalopathies (TSEs), are invariably fatal neurodegenerative disorders that can be sporadic, inherited or acquired by infection. In humans, TSEs comprise three major groups showing a wide phenotypic heterogeneity: Creutzfeldt-Jakob disease (CJD),

  13. Comparative Study of Prions in Iatrogenic and Sporadic Creutzfeldt-Jakob Disease

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    Xiao, Xiangzhu; Yuan, Jue; Qing, Liuting; Cali, Ignazio; Mikol, Jacqueline; Delisle, Marie-Bernadette; Uro-Coste, Emmanuelle; Zeng, Liang; Abouelsaad, Mai; Gazgalis, Dimitris; Martinez, Manuel Camacho; Wang, Gong-Xian; Brown, Paul; Ironside, James W.; Gambetti, Pierluigi; Kong, Qingzhong; Zou, Wen-Quan

    2014-01-01

    Differentiating iatrogenic Creutzfeldt-Jakob disease (iCJD) from sporadic CJD (sCJD) would be useful for the identification and prevention of human-to-human prion transmission. Currently, the diagnosis of iCJD depends on identification of a recognized source of contamination to which patients have been exposed, in addition to fulfilling basic requirements for the establishment of diagnosis of CJD. Attempts to identify differences in clinical manifestations, neuropathological changes and pathological prion protein (PrPSc) between iCJD and sCJD have been unsuccessful. In the present study, using a variety of more sophisticated methods including sucrose step gradient sedimentation, conformational stability immunoassay, protein misfolding cyclic amplification (PMCA), fragment-mapping, and transmission study, we show no significant differences in gel profiles, oligomeric state, conformational stability and infectivity of PrPSc between iCJD and sCJD. However, using PMCA, we find that convertibility and amplification efficiency of PrPSc is greater in iCJD than in sCJD in a polymorphism-dependent manner. Moreover, two protease-resistant PrP C-terminal fragments (termed PrP-CTF12/13) were detected in all 9 cases of sCJD but not in 6 of 8 cases of iCJD tested in this study. The use of fragment mapping- and PMCA-based assays thus provides a means to distinguish most cases of iCJD from sCJD. PMID:25419482

  14. Co-existence of scrapie prion protein types 1 and 2 in sporadic Creutzfeldt-Jakob disease: its effect on the phenotype and prion-type characteristics

    NARCIS (Netherlands)

    Cali, I.; Castellani, R.; Alshekhlee, A.; Cohen, Y.; Blevins, J.; Yuan, J.; Langeveld, J.P.M.; Parchi, P.; Safar, J.G.; Zou, W.Q.; Gambetti, P.

    2009-01-01

    Five phenotypically distinct subtypes have been identified in sporadic Creutzfeldt-Jakob disease (sCJD), based on the methionine/valine polymorphic genotype of codon 129 of the prion protein (PrP) gene and the presence of either one of the two protease K-resistant scrapie prion protein (PrPSc) types

  15. Subtype and regional regulation of prion biomarkers in sporadic Creutzfeldt-Jakob disease.

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    Llorens, Franc; Zafar, Saima; Ansoleaga, Belén; Shafiq, Mohsin; Blanco, Rosi; Carmona, Marga; Grau-Rivera, Oriol; Nos, Carlos; Gelpí, Ellen; Del Río, José Antonio; Zerr, Inga; Ferrer, Isidre

    2015-08-01

    Creutzfeldt-Jakob disease (CJD) is a rapid progressive neurological disease leading to dementia and death. Prion biomarkers are altered in the cerebrospinal fluid (CSF) of CJD patients, but the pathogenic mechanisms underlying these alterations are still unknown. The present study examined prion biomarker levels in the brain and CSF of sporadic CJD (sCJD) cases and their correlation with neuropathological lesion profiles. The expression levels of 14-3-3, Tau, phospho-Tau and α-synuclein were measured in the CSF and brain of sCJD cases in a subtype- and region-specific manner. In addition, the activity of prion biomarker kinases, the expression levels of CJD hallmarks and the most frequent neuropathological sCJD findings were analysed. Prion biomarkers levels were increased in the CSF of sCJD patients; however, correlations between mRNA, total protein and their phosphorylated forms in brain were different. The observed downregulation of the main Tau kinase, GSK3, in sCJD brain samples may help to explain the differential phospho-Tau/Tau ratios between sCJD and other dementias in the CSF. Importantly, CSF biomarkers levels do not necessarily correlate with sCJD neuropathological findings. Present findings indicate that prion biomarkers levels in sCJD tissues and their release into the CSF are differentially regulated following specific modulated responses, and suggest a functional role for these proteins in sCJD pathogenesis. © 2014 British Neuropathological Society.

  16. Recombinant human prion protein inhibits prion propagation in vitro.

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    Yuan, Jue; Zhan, Yi-An; Abskharon, Romany; Xiao, Xiangzhu; Martinez, Manuel Camacho; Zhou, Xiaochen; Kneale, Geoff; Mikol, Jacqueline; Lehmann, Sylvain; Surewicz, Witold K; Castilla, Joaquín; Steyaert, Jan; Zhang, Shulin; Kong, Qingzhong; Petersen, Robert B; Wohlkonig, Alexandre; Zou, Wen-Quan

    2013-10-09

    Prion diseases are associated with the conformational conversion of the cellular prion protein (PrP(C)) into the pathological scrapie isoform (PrP(Sc)) in the brain. Both the in vivo and in vitro conversion of PrP(C) into PrP(Sc) is significantly inhibited by differences in amino acid sequence between the two molecules. Using protein misfolding cyclic amplification (PMCA), we now report that the recombinant full-length human PrP (rHuPrP23-231) (that is unglycosylated and lacks the glycophosphatidylinositol anchor) is a strong inhibitor of human prion propagation. Furthermore, rHuPrP23-231 also inhibits mouse prion propagation in a scrapie-infected mouse cell line. Notably, it binds to PrP(Sc), but not PrP(C), suggesting that the inhibitory effect of recombinant PrP results from blocking the interaction of brain PrP(C) with PrP(Sc). Our findings suggest a new avenue for treating prion diseases, in which a patient's own unglycosylated and anchorless PrP is used to inhibit PrP(Sc) propagation without inducing immune response side effects.

  17. Variably Protease-Sensitive Prionopathy: A New Sporadic Disease of the Prion Protein

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    Zou, Wen-Quan; Puoti, Gianfranco; Xiao, Xiangzhu; Yuan, Jue; Qing, Liuting; Cali, Ignazio; Shimoji, Miyuki; Langeveld, Jan P. M.; Castellani, Rudy; Notari, Silvio; Crain, Barbara; Schmidt, Robert E.; Geschwind, Michael; DeArmond, Stephen J.; Cairns, Nigel J.; Dickson, Dennis; Honig, Lawrence; Torres, Juan Maria; Mastrianni, James; Capellari, Sabina; Giaccone, Giorgio; Belay, Ermias D.; Schonberger, Lawrence B.; Cohen, Mark; Perry, George; Kong, Qingzhong; Parchi, Piero; Tagliavini, Fabrizio; Gambetti, Pierluigi

    2011-01-01

    Objective The objective of the study is to report 2 new genotypic forms of protease-sensitive prionopathy (PSPr), a novel prion disease described in 2008, in 11 subjects all homozygous for valine at codon 129 of the prion protein (PrP) gene (129VV). The 2 new PSPr forms affect individuals who are either homozygous for methionine (129MM) or heterozygous for methionine/valine (129MV). Methods Fifteen affected subjects with 129MM, 129MV, and 129VV underwent comparative evaluation at the National Prion Disease Pathology Surveillance Center for clinical, histopathologic, immunohistochemical, genotypical, and PrP characteristics. Results Disease duration (between 22 and 45 months) was significantly different in the 129VV and 129MV subjects. Most other phenotypic features along with the PrP electrophoretic profile were similar but distinguishable in the 3 129 genotypes. A major difference laid in the sensitivity to protease digestion of the disease-associated PrP, which was high in 129VV but much lower, or altogether lacking, in 129MV and 129MM. This difference prompted the substitution of the original designation with “variably protease-sensitive prionopathy” (VPSPr). None of the subjects had mutations in the PrP gene coding region. Interpretation Because all 3 129 genotypes are involved, and are associated with distinguishable phenotypes, VPSPr becomes the second sporadic prion protein disease with this feature after Creutzfeldt-Jakob disease, originally reported in 1920. However, the characteristics of the abnormal prion protein suggest that VPSPr is different from typical prion diseases, and perhaps more akin to subtypes of Gerstmann-Sträussler-Scheinker disease. PMID:20695009

  18. Differential overexpression of SERPINA3 in human prion diseases.

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    Vanni, S; Moda, F; Zattoni, M; Bistaffa, E; De Cecco, E; Rossi, M; Giaccone, G; Tagliavini, F; Haïk, S; Deslys, J P; Zanusso, G; Ironside, J W; Ferrer, I; Kovacs, G G; Legname, G

    2017-11-15

    Prion diseases are fatal neurodegenerative disorders with sporadic, genetic or acquired etiologies. The molecular alterations leading to the onset and the spreading of these diseases are still unknown. In a previous work we identified a five-gene signature able to distinguish intracranially BSE-infected macaques from healthy ones, with SERPINA3 showing the most prominent dysregulation. We analyzed 128 suitable frontal cortex samples, from prion-affected patients (variant Creutzfeldt-Jakob disease (vCJD) n = 20, iatrogenic CJD (iCJD) n = 11, sporadic CJD (sCJD) n = 23, familial CJD (gCJD) n = 17, fatal familial insomnia (FFI) n = 9, Gerstmann-Sträussler-Scheinker syndrome (GSS)) n = 4), patients with Alzheimer disease (AD, n = 14) and age-matched controls (n = 30). Real Time-quantitative PCR was performed for SERPINA3 transcript, and ACTB, RPL19, GAPDH and B2M were used as reference genes. We report SERPINA3 to be strongly up-regulated in the brain of all human prion diseases, with only a mild up-regulation in AD. We show that this striking up-regulation, both at the mRNA and at the protein level, is present in all types of human prion diseases analyzed, although to a different extent for each specific disorder. Our data suggest that SERPINA3 may be involved in the pathogenesis and the progression of prion diseases, representing a valid tool for distinguishing different forms of these disorders in humans.

  19. Prions

    Directory of Open Access Journals (Sweden)

    W. Bodemer

    2016-09-01

    BSE is always unknown. Telemetry revealed a shift in sleep–wake cycles early on, long before behavioral changes or clinical symptoms appeared. Pathology confirmed non-neuronal tissue as hidden places where prions exist. The rhesus model also allowed first comparative studies of epigenetic modifications on RNA in peripheral blood and brain tissue collected from uninfected and prion-infected animals. To conclude, our studies clearly demonstrated that this model is valid since progression to disease is almost identical to human CJD.

  20. Atypical scrapie prions from sheep and lack of disease in transgenic mice overexpressing human prion protein.

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    Wadsworth, Jonathan D F; Joiner, Susan; Linehan, Jacqueline M; Balkema-Buschmann, Anne; Spiropoulos, John; Simmons, Marion M; Griffiths, Peter C; Groschup, Martin H; Hope, James; Brandner, Sebastian; Asante, Emmanuel A; Collinge, John

    2013-11-01

    Public and animal health controls to limit human exposure to animal prions are focused on bovine spongiform encephalopathy (BSE), but other prion strains in ruminants may also have zoonotic potential. One example is atypical/Nor98 scrapie, which evaded statutory diagnostic methods worldwide until the early 2000s. To investigate whether sheep infected with scrapie prions could be another source of infection, we inoculated transgenic mice that overexpressed human prion protein with brain tissue from sheep with natural field cases of classical and atypical scrapie, sheep with experimental BSE, and cattle with BSE. We found that these mice were susceptible to BSE prions, but disease did not develop after prolonged postinoculation periods when mice were inoculated with classical or atypical scrapie prions. These data are consistent with the conclusion that prion disease is less likely to develop in humans after exposure to naturally occurring prions of sheep than after exposure to epizootic BSE prions of ruminants.

  1. Transmission Properties of Human PrP 102L Prions Challenge the Relevance of Mouse Models of GSS.

    Science.gov (United States)

    Asante, Emmanuel A; Grimshaw, Andrew; Smidak, Michelle; Jakubcova, Tatiana; Tomlinson, Andrew; Jeelani, Asif; Hamdan, Shyma; Powell, Caroline; Joiner, Susan; Linehan, Jacqueline M; Brandner, Sebastian; Wadsworth, Jonathan D F; Collinge, John

    2015-07-01

    Inherited prion disease (IPD) is caused by autosomal-dominant pathogenic mutations in the human prion protein (PrP) gene (PRNP). A proline to leucine substitution at PrP residue 102 (P102L) is classically associated with Gerstmann-Sträussler-Scheinker (GSS) disease but shows marked clinical and neuropathological variability within kindreds that may be caused by variable propagation of distinct prion strains generated from either PrP 102L or wild type PrP. To-date the transmission properties of prions propagated in P102L patients remain ill-defined. Multiple mouse models of GSS have focused on mutating the corresponding residue of murine PrP (P101L), however murine PrP 101L, a novel PrP primary structure, may not have the repertoire of pathogenic prion conformations necessary to accurately model the human disease. Here we describe the transmission properties of prions generated in human PrP 102L expressing transgenic mice that were generated after primary challenge with ex vivo human GSS P102L or classical CJD prions. We show that distinct strains of prions were generated in these mice dependent upon source of the inoculum (either GSS P102L or CJD brain) and have designated these GSS-102L and CJD-102L prions, respectively. GSS-102L prions have transmission properties distinct from all prion strains seen in sporadic and acquired human prion disease. Significantly, GSS-102L prions appear incapable of transmitting disease to conventional mice expressing wild type mouse PrP, which contrasts strikingly with the reported transmission properties of prions generated in GSS P102L-challenged mice expressing mouse PrP 101L. We conclude that future transgenic modeling of IPDs should focus exclusively on expression of mutant human PrP, as other approaches may generate novel experimental prion strains that are unrelated to human disease.

  2. Yeast prions and human prion-like proteins: sequence features and prediction methods.

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    Cascarina, Sean M; Ross, Eric D

    2014-06-01

    Prions are self-propagating infectious protein isoforms. A growing number of prions have been identified in yeast, each resulting from the conversion of soluble proteins into an insoluble amyloid form. These yeast prions have served as a powerful model system for studying the causes and consequences of prion aggregation. Remarkably, a number of human proteins containing prion-like domains, defined as domains with compositional similarity to yeast prion domains, have recently been linked to various human degenerative diseases, including amyotrophic lateral sclerosis. This suggests that the lessons learned from yeast prions may help in understanding these human diseases. In this review, we examine what has been learned about the amino acid sequence basis for prion aggregation in yeast, and how this information has been used to develop methods to predict aggregation propensity. We then discuss how this information is being applied to understand human disease, and the challenges involved in applying yeast prediction methods to higher organisms.

  3. Coexistence of protease sensitive and resistant prion protein in 129VV homozygous sporadic Creutzfeldt–Jakob disease: a case report

    Directory of Open Access Journals (Sweden)

    Rodríguez-Martínez Ana B

    2012-10-01

    Full Text Available Abstract Introduction The coexistence of different molecular types of classical protease-resistant prion protein in the same individual have been described, however, the simultaneous finding of these with the recently described protease-sensitive variant or variably protease-sensitive prionopathy has, to the best of our knowledge, not yet been reported. Case presentation A 74-year-old Caucasian woman showed a sporadic Creutzfeldt–Jakob disease clinical phenotype with reactive depression, followed by cognitive impairment, akinetic-rigid Parkinsonism with pseudobulbar syndrome and gait impairment with motor apraxia, visuospatial disorientation, and evident frontal dysfunction features such as grasping, palmomental reflex and brisk perioral reflexes. She died at age 77. Neuropathological findings showed: spongiform change in the patient’s cerebral cortex, striatum, thalamus and molecular layer of the cerebellum with proteinase K-sensitive synaptic-like, dot-like or target-like prion protein deposition in the cortex, thalamus and striatum; proteinase K-resistant prion protein in the same regions; and elongated plaque-like proteinase K-resistant prion protein in the molecular layer of the cerebellum. Molecular analysis of prion protein after proteinase K digestion revealed decreased signal intensity in immunoblot, a ladder-like protein pattern, and a 71% reduction of PrPSc signal relative to non-digested material. Her cerebellum showed a 2A prion protein type largely resistant to proteinase K. Genotype of polymorphism at codon 129 was valine homozygous. Conclusion Molecular typing of prion protein along with clinical and neuropathological data revealed, to the best of our knowledge, the first case of the coexistence of different protease-sensitive prion proteins in the same patient in a rare case that did not fulfill the current clinical diagnostic criteria for either probable or possible sporadic Creutzfeldt–Jakob disease. This highlights the

  4. Molecular Modeling of Prion Transmission to Humans

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    Etienne Levavasseur

    2014-10-01

    Full Text Available Using different prion strains, such as the variant Creutzfeldt-Jakob disease agent and the atypical bovine spongiform encephalopathy agents, and using transgenic mice expressing human or bovine prion protein, we assessed the reliability of protein misfolding cyclic amplification (PMCA to model interspecies and genetic barriers to prion transmission. We compared our PMCA results with in vivo transmission data characterized by attack rates, i.e., the percentage of inoculated mice that developed the disease. Using 19 seed/substrate combinations, we observed that a significant PMCA amplification was only obtained when the mouse line used as substrate is susceptible to the corresponding strain. Our results suggest that PMCA provides a useful tool to study genetic barriers to transmission and to study the zoonotic potential of emerging prion strains.

  5. Chronic wasting disease prions are not transmissible to transgenic mice overexpressing human prion protein.

    Science.gov (United States)

    Sandberg, Malin K; Al-Doujaily, Huda; Sigurdson, Christina J; Glatzel, Markus; O'Malley, Catherine; Powell, Caroline; Asante, Emmanuel A; Linehan, Jacqueline M; Brandner, Sebastian; Wadsworth, Jonathan D F; Collinge, John

    2010-10-01

    Chronic wasting disease (CWD) is a prion disease that affects free-ranging and captive cervids, including mule deer, white-tailed deer, Rocky Mountain elk and moose. CWD-infected cervids have been reported in 14 USA states, two Canadian provinces and in South Korea. The possibility of a zoonotic transmission of CWD prions via diet is of particular concern in North America where hunting of cervids is a popular sport. To investigate the potential public health risks posed by CWD prions, we have investigated whether intracerebral inoculation of brain and spinal cord from CWD-infected mule deer transmits prion infection to transgenic mice overexpressing human prion protein with methionine or valine at polymorphic residue 129. These transgenic mice have been utilized in extensive transmission studies of human and animal prion disease and are susceptible to BSE and vCJD prions, allowing comparison with CWD. Here, we show that these mice proved entirely resistant to infection with mule deer CWD prions arguing that the transmission barrier associated with this prion strain/host combination is greater than that observed with classical BSE prions. However, it is possible that CWD may be caused by multiple prion strains. Further studies will be required to evaluate the transmission properties of distinct cervid prion strains as they are characterized.

  6. Structural determinants of phenotypic diversity and replication rate of human prions.

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    Jiri G Safar

    2015-04-01

    Full Text Available The infectious pathogen responsible for prion diseases is the misfolded, aggregated form of the prion protein, PrPSc. In contrast to recent progress in studies of laboratory rodent-adapted prions, current understanding of the molecular basis of human prion diseases and, especially, their vast phenotypic diversity is very limited. Here, we have purified proteinase resistant PrPSc aggregates from two major phenotypes of sporadic Creutzfeldt-Jakob disease (sCJD, determined their conformational stability and replication tempo in vitro, as well as characterized structural organization using recently emerged approaches based on hydrogen/deuterium (H/D exchange coupled with mass spectrometry. Our data clearly demonstrate that these phenotypically distant prions differ in a major way with regard to their structural organization, both at the level of the polypeptide backbone (as indicated by backbone amide H/D exchange data as well as the quaternary packing arrangements (as indicated by H/D exchange kinetics for histidine side chains. Furthermore, these data indicate that, in contrast to previous observations on yeast and some murine prion strains, the replication rate of sCJD prions is primarily determined not by conformational stability but by specific structural features that control the growth rate of prion protein aggregates.

  7. Diagnostic and prognostic value of human prion detection in cerebrospinal fluid.

    Science.gov (United States)

    Foutz, Aaron; Appleby, Brian S; Hamlin, Clive; Liu, Xiaoqin; Yang, Sheng; Cohen, Yvonne; Chen, Wei; Blevins, Janis; Fausett, Cameron; Wang, Han; Gambetti, Pierluigi; Zhang, Shulin; Hughson, Andrew; Tatsuoka, Curtis; Schonberger, Lawrence B; Cohen, Mark L; Caughey, Byron; Safar, Jiri G

    2017-01-01

    Several prion amplification systems have been proposed for detection of prions in cerebrospinal fluid (CSF), most recently, the measurements of prion seeding activity with second-generation real-time quaking-induced conversion (RT-QuIC). The objective of this study was to investigate the diagnostic performance of the RT-QuIC prion test in the broad phenotypic spectrum of prion diseases. We performed CSF RT-QuIC testing in 2,141 patients who had rapidly progressive neurological disorders, determined diagnostic sensitivity and specificity in 272 cases that were autopsied, and evaluated the impact of mutations and polymorphisms in the PRNP gene, and type 1 or type 2 human prions on diagnostic performance. The 98.5% diagnostic specificity and 92% sensitivity of CSF RT-QuIC in a blinded retrospective analysis matched the 100% specificity and 95% sensitivity of a blind prospective study. The CSF RT-QuIC differentiated 94% of cases of sporadic Creutzfeldt-Jakob disease (sCJD) MM1 from the sCJD MM2 phenotype, and 80% of sCJD VV2 from sCJD VV1. The mixed prion type 1-2 and cases heterozygous for codon 129 generated intermediate CSF RT-QuIC patterns, whereas genetic prion diseases revealed distinct profiles for each PRNP gene mutation. The diagnostic performance of the improved CSF RT-QuIC is superior to surrogate marker tests for prion diseases such as 14-3-3 and tau proteins, and together with PRNP gene sequencing the test allows the major prion subtypes to be differentiated in vivo. This differentiation facilitates prediction of the clinicopathological phenotype and duration of the disease-two important considerations for envisioned therapeutic interventions. ANN NEUROL 2017;81:79-92. © 2016 American Neurological Association.

  8. Increased infectivity of anchorless mouse scrapie prions in transgenic mice overexpressing human prion protein.

    Science.gov (United States)

    Race, Brent; Phillips, Katie; Meade-White, Kimberly; Striebel, James; Chesebro, Bruce

    2015-06-01

    Prion protein (PrP) is found in all mammals, mostly as a glycoprotein anchored to the plasma membrane by a C-terminal glycosylphosphatidylinositol (GPI) linkage. Following prion infection, host protease-sensitive prion protein (PrPsen or PrPC) is converted into an abnormal, disease-associated, protease-resistant form (PrPres). Biochemical characteristics, such as the PrP amino acid sequence, and posttranslational modifications, such as glycosylation and GPI anchoring, can affect the transmissibility of prions as well as the biochemical properties of the PrPres generated. Previous in vivo studies on the effects of GPI anchoring on prion infectivity have not examined cross-species transmission. In this study, we tested the effect of lack of GPI anchoring on a species barrier model using mice expressing human PrP. In this model, anchorless 22L prions derived from tg44 mice were more infectious than 22L prions derived from C57BL/10 mice when tested in tg66 transgenic mice, which expressed wild-type anchored human PrP at 8- to 16-fold above normal. Thus, the lack of the GPI anchor on the PrPres from tg44 mice appeared to reduce the effect of the mouse-human PrP species barrier. In contrast, neither source of prions induced disease in tgRM transgenic mice, which expressed human PrP at 2- to 4-fold above normal. Prion protein (PrP) is found in all mammals, usually attached to cells by an anchor molecule called GPI. Following prion infection, PrP is converted into a disease-associated form (PrPres). While most prion diseases are species specific, this finding is not consistent, and species barriers differ in strength. The amino acid sequence of PrP varies among species, and this variability affects prion species barriers. However, other PrP modifications, including glycosylation and GPI anchoring, may also influence cross-species infectivity. We studied the effect of PrP GPI anchoring using a mouse-to-human species barrier model. Experiments showed that prions produced by

  9. Emergence of two prion subtypes in ovine PrP transgenic mice infected with human MM2-cortical Creutzfeldt-Jakob disease prions.

    Science.gov (United States)

    Chapuis, Jérôme; Moudjou, Mohammed; Reine, Fabienne; Herzog, Laetitia; Jaumain, Emilie; Chapuis, Céline; Quadrio, Isabelle; Boulliat, Jacques; Perret-Liaudet, Armand; Dron, Michel; Laude, Hubert; Rezaei, Human; Béringue, Vincent

    2016-02-05

    Mammalian prions are proteinaceous pathogens responsible for a broad range of fatal neurodegenerative diseases in humans and animals. These diseases can occur spontaneously, such as Creutzfeldt-Jakob disease (CJD) in humans, or be acquired or inherited. Prions are primarily formed of macromolecular assemblies of the disease-associated prion protein PrP(Sc), a misfolded isoform of the host-encoded prion protein PrP(C). Within defined host-species, prions can exist as conformational variants or strains. Based on both the M/V polymorphism at codon 129 of PrP and the electrophoretic signature of PrP(Sc) in the brain, sporadic CJD is classified in different subtypes, which may encode different strains. A transmission barrier, the mechanism of which remains unknown, limits prion cross-species propagation. To adapt to the new host, prions have the capacity to 'mutate' conformationally, leading to the emergence of a variant with new biological properties. Here, we transmitted experimentally one rare subtype of human CJD, designated cortical MM2 (129 MM with type 2 PrP(Sc)), to transgenic mice overexpressing either human or the VRQ allele of ovine PrP(C). In marked contrast with the reported absence of transmission to knock-in mice expressing physiological levels of human PrP, this subtype transmitted faithfully to mice overexpressing human PrP, and exhibited unique strain features. Onto the ovine PrP sequence, the cortical MM2 subtype abruptly evolved on second passage, thereby allowing emergence of a pair of strain variants with distinct PrP(Sc) biochemical characteristics and differing tropism for the central and lymphoid tissues. These two strain components exhibited remarkably distinct replicative properties in cell-free amplification assay, allowing the 'physical' cloning of the minor, lymphotropic component, and subsequent isolation in ovine PrP mice and RK13 cells. Here, we provide in-depth assessment of the transmissibility and evolution of one rare subtype of

  10. Implications of prion adaptation and evolution paradigm for human neurodegenerative diseases.

    Science.gov (United States)

    Kabir, M Enamul; Safar, Jiri G

    2014-01-01

    There is a growing body of evidence indicating that number of human neurodegenerative diseases, including Alzheimer disease, Parkinson disease, fronto-temporal dementias, and amyotrophic lateral sclerosis, propagate in the brain via prion-like intercellular induction of protein misfolding. Prions cause lethal neurodegenerative diseases in humans, the most prevalent being sporadic Creutzfeldt-Jakob disease (sCJD); they self-replicate and spread by converting the cellular form of prion protein (PrP(C)) to a misfolded pathogenic conformer (PrP(Sc)). The extensive phenotypic heterogeneity of human prion diseases is determined by polymorphisms in the prion protein gene, and by prion strain-specific conformation of PrP(Sc). Remarkably, even though informative nucleic acid is absent, prions may undergo rapid adaptation and evolution in cloned cells and upon crossing the species barrier. In the course of our investigation of this process, we isolated distinct populations of PrP(Sc) particles that frequently co-exist in sCJD. The human prion particles replicate independently and undergo competitive selection of those with lower initial conformational stability. Exposed to mutant substrate, the winning PrP(Sc) conformers are subject to further evolution by natural selection of the subpopulation with the highest replication rate due to the lowest stability. Thus, the evolution and adaptation of human prions is enabled by a dynamic collection of distinct populations of particles, whose evolution is governed by the selection of progressively less stable, faster replicating PrP(Sc) conformers. This fundamental biological mechanism may explain the drug resistance that some prions gained after exposure to compounds targeting PrP(Sc). Whether the phenotypic heterogeneity of other neurodegenerative diseases caused by protein misfolding is determined by the spectrum of misfolded conformers (strains) remains to be established. However, the prospect that these conformers may evolve and

  11. Prions in Variably Protease-Sensitive Prionopathy: An Update

    NARCIS (Netherlands)

    Zou, W.Q.; Gambetti, P.; Xiao, X.; Yuan, J.; Langeveld, J.P.M.; Pirisinu, L.

    2013-01-01

    Human prion diseases, including sporadic, familial, and acquired forms such as Creutzfeldt-Jakob disease (CJD), are caused by prions in which an abnormal prion protein (PrPSc) derived from its normal cellular isoform (PrPC) is the only known component. The recently-identified variably

  12. A naturally occurring variant of the human prion protein completely prevents prion disease.

    Science.gov (United States)

    Asante, Emmanuel A; Smidak, Michelle; Grimshaw, Andrew; Houghton, Richard; Tomlinson, Andrew; Jeelani, Asif; Jakubcova, Tatiana; Hamdan, Shyma; Richard-Londt, Angela; Linehan, Jacqueline M; Brandner, Sebastian; Alpers, Michael; Whitfield, Jerome; Mead, Simon; Wadsworth, Jonathan D F; Collinge, John

    2015-06-25

    Mammalian prions, transmissible agents causing lethal neurodegenerative diseases, are composed of assemblies of misfolded cellular prion protein (PrP). A novel PrP variant, G127V, was under positive evolutionary selection during the epidemic of kuru--an acquired prion disease epidemic of the Fore population in Papua New Guinea--and appeared to provide strong protection against disease in the heterozygous state. Here we have investigated the protective role of this variant and its interaction with the common, worldwide M129V PrP polymorphism. V127 was seen exclusively on a M129 PRNP allele. We demonstrate that transgenic mice expressing both variant and wild-type human PrP are completely resistant to both kuru and classical Creutzfeldt-Jakob disease (CJD) prions (which are closely similar) but can be infected with variant CJD prions, a human prion strain resulting from exposure to bovine spongiform encephalopathy prions to which the Fore were not exposed. Notably, mice expressing only PrP V127 were completely resistant to all prion strains, demonstrating a different molecular mechanism to M129V, which provides its relative protection against classical CJD and kuru in the heterozygous state. Indeed, this single amino acid substitution (G→V) at a residue invariant in vertebrate evolution is as protective as deletion of the protein. Further study in transgenic mice expressing different ratios of variant and wild-type PrP indicates that not only is PrP V127 completely refractory to prion conversion but acts as a potent dose-dependent inhibitor of wild-type prion propagation.

  13. Human prion diseases in the United States.

    Directory of Open Access Journals (Sweden)

    Robert C Holman

    Full Text Available BACKGROUND: Prion diseases are a family of rare, progressive, neurodegenerative disorders that affect humans and animals. The most common form of human prion disease, Creutzfeldt-Jakob disease (CJD, occurs worldwide. Variant CJD (vCJD, a recently emerged human prion disease, is a zoonotic foodborne disorder that occurs almost exclusively in countries with outbreaks of bovine spongiform encephalopathy. This study describes the occurrence and epidemiology of CJD and vCJD in the United States. METHODOLOGY/PRINCIPAL FINDINGS: Analysis of CJD and vCJD deaths using death certificates of US residents for 1979-2006, and those identified through other surveillance mechanisms during 1996-2008. Since CJD is invariably fatal and illness duration is usually less than one year, the CJD incidence is estimated as the death rate. During 1979 through 2006, an estimated 6,917 deaths with CJD as a cause of death were reported in the United States, an annual average of approximately 247 deaths (range 172-304 deaths. The average annual age-adjusted incidence for CJD was 0.97 per 1,000,000 persons. Most (61.8% of the CJD deaths occurred among persons >or=65 years of age for an average annual incidence of 4.8 per 1,000,000 persons in this population. Most deaths were among whites (94.6%; the age-adjusted incidence for whites was 2.7 times higher than that for blacks (1.04 and 0.40, respectively. Three patients who died since 2004 were reported with vCJD; epidemiologic evidence indicated that their infection was acquired outside of the United States. CONCLUSION/SIGNIFICANCE: Surveillance continues to show an annual CJD incidence rate of about 1 case per 1,000,000 persons and marked differences in CJD rates by age and race in the United States. Ongoing surveillance remains important for monitoring the stability of the CJD incidence rates, and detecting occurrences of vCJD and possibly other novel prion diseases in the United States.

  14. Co-existence of Distinct Prion Types Enables Conformational Evolution of Human PrPSc by Competitive Selection*

    Science.gov (United States)

    Haldiman, Tracy; Kim, Chae; Cohen, Yvonne; Chen, Wei; Blevins, Janis; Qing, Liuting; Cohen, Mark L.; Langeveld, Jan; Telling, Glenn C.; Kong, Qingzhong; Safar, Jiri G.

    2013-01-01

    The unique phenotypic characteristics of mammalian prions are thought to be encoded in the conformation of pathogenic prion proteins (PrPSc). The molecular mechanism responsible for the adaptation, mutation, and evolution of prions observed in cloned cells and upon crossing the species barrier remains unsolved. Using biophysical techniques and conformation-dependent immunoassays in tandem, we isolated two distinct populations of PrPSc particles with different conformational stabilities and aggregate sizes, which frequently co-exist in the most common human prion disease, sporadic Creutzfeldt-Jakob disease. The protein misfolding cyclic amplification replicates each of the PrPSc particle types independently and leads to the competitive selection of those with lower initial conformational stability. In serial propagation with a nonglycosylated mutant PrPC substrate, the dominant PrPSc conformers are subject to further evolution by natural selection of the subpopulation with the highest replication rate due to its lowest stability. Cumulatively, the data show that sporadic Creutzfeldt-Jakob disease PrPSc is not a single conformational entity but a dynamic collection of two distinct populations of particles. This implies the co-existence of different prions, whose adaptation and evolution are governed by the selection of progressively less stable, faster replicating PrPSc conformers. PMID:23974118

  15. Infectious prion diseases in humans: cannibalism, iatrogenicity and zoonoses.

    Science.gov (United States)

    Haïk, Stéphane; Brandel, Jean-Philippe

    2014-08-01

    In contrast with other neurodegenerative disorders associated to protein misfolding, human prion diseases include infectious forms (also called transmitted forms) such as kuru, iatrogenic Creutzfeldt-Jakob disease and variant Creutzfeldt-Jakob disease. The transmissible agent is thought to be solely composed of the abnormal isoform (PrP(Sc)) of the host-encoded prion protein that accumulated in the central nervous system of affected individuals. Compared to its normal counterpart, PrP(Sc) is β-sheet enriched and aggregated and its propagation is based on an autocatalytic conversion process. Increasing evidence supports the view that conformational variations of PrP(Sc) encoded the biological properties of the various prion strains that have been isolated by transmission studies in experimental models. Infectious forms of human prion diseases played a pivotal role in the emergence of the prion concept and in the characterization of the very unconventional properties of prions. They provide a unique model to understand how prion strains are selected and propagate in humans. Here, we review and discuss how genetic factors interplay with strain properties and route of transmission to influence disease susceptibility, incubation period and phenotypic expression in the light of the kuru epidemics due to ritual endocannibalism, the various series iatrogenic diseases secondary to extractive growth hormone treatment or dura mater graft and the epidemics of variant Creutzfeldt-Jakob disease linked to dietary exposure to the agent of bovine spongiform encephalopathy. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. UK Iatrogenic Creutzfeldt-Jakob disease: investigating human prion transmission across genotypic barriers using human tissue-based and molecular approaches.

    Science.gov (United States)

    Ritchie, Diane L; Barria, Marcelo A; Peden, Alexander H; Yull, Helen M; Kirkpatrick, James; Adlard, Peter; Ironside, James W; Head, Mark W

    2017-04-01

    Creutzfeldt-Jakob disease (CJD) is the prototypic human prion disease that occurs most commonly in sporadic and genetic forms, but it is also transmissible and can be acquired through medical procedures, resulting in iatrogenic CJD (iCJD). The largest numbers of iCJD cases that have occurred worldwide have resulted from contaminated cadaveric pituitary-derived human growth hormone (hGH) and its use to treat primary and secondary growth hormone deficiency. We report a comprehensive, tissue-based and molecular genetic analysis of the largest series of UK hGH-iCJD cases reported to date, including in vitro kinetic molecular modelling of genotypic factors influencing prion transmission. The results show the interplay of prion strain and host genotype in governing the molecular, pathological and temporal characteristics of the UK hGH-iCJD epidemic and provide insights into the adaptive mechanisms involved when prions cross genotypic barriers. We conclude that all of the available evidence is consistent with the hypothesis that the UK hGH-iCJD epidemic resulted from transmission of the V2 human prion strain, which is associated with the second most common form of sporadic CJD.

  17. Experimental sheep BSE prions generate the vCJD phenotype when serially passaged in transgenic mice expressing human prion protein.

    Science.gov (United States)

    Joiner, Susan; Asante, Emmanuel A; Linehan, Jacqueline M; Brock, Lara; Brandner, Sebastian; Bellworthy, Susan J; Simmons, Marion M; Hope, James; Collinge, John; Wadsworth, Jonathan D F

    2018-03-15

    The epizootic prion disease of cattle, bovine spongiform encephalopathy (BSE), causes variant Creutzfeldt-Jakob disease (vCJD) in humans following dietary exposure. While it is assumed that all cases of vCJD attributed to a dietary aetiology are related to cattle BSE, sheep and goats are susceptible to experimental oral challenge with cattle BSE prions and farmed animals in the UK were undoubtedly exposed to BSE-contaminated meat and bone meal during the late 1980s and early 1990s. Although no natural field cases of sheep BSE have been identified, it cannot be excluded that some BSE-infected sheep might have entered the European human food chain. Evaluation of the zoonotic potential of sheep BSE prions has been addressed by examining the transmission properties of experimental brain isolates in transgenic mice that express human prion protein, however to-date there have been relatively few studies. Here we report that serial passage of experimental sheep BSE prions in transgenic mice expressing human prion protein with methionine at residue 129 produces the vCJD phenotype that mirrors that seen when the same mice are challenged with vCJD prions from patient brain. These findings are congruent with those reported previously by another laboratory, and thereby strongly reinforce the view that sheep BSE prions could have acted as a causal agent of vCJD within Europe. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  18. Rapid and Quantitative Assay of Amyloid-Seeding Activity in Human Brains Affected with Prion Diseases.

    Directory of Open Access Journals (Sweden)

    Hanae Takatsuki

    Full Text Available The infectious agents of the transmissible spongiform encephalopathies are composed of amyloidogenic prion protein, PrPSc. Real-time quaking-induced conversion can amplify very small amounts of PrPSc seeds in tissues/body fluids of patients or animals. Using this in vitro PrP-amyloid amplification assay, we quantitated the seeding activity of affected human brains. End-point assay using serially diluted brain homogenates of sporadic Creutzfeldt-Jakob disease patients demonstrated that 50% seeding dose (SD50 is reached approximately 10(10/g brain (values varies 10(8.79-10.63/g. A genetic case (GSS-P102L yielded a similar level of seeding activity in an autopsy brain sample. The range of PrPSc concentrations in the samples, determined by dot-blot assay, was 0.6-5.4 μg/g brain; therefore, we estimated that 1 SD50 unit was equivalent to 0.06-0.27 fg of PrPSc. The SD50 values of the affected brains dropped more than three orders of magnitude after autoclaving at 121°C. This new method for quantitation of human prion activity provides a new way to reduce the risk of iatrogenic prion transmission.

  19. Proteomics analyses for the global proteins in the brain tissues of different human prion diseases.

    Science.gov (United States)

    Shi, Qi; Chen, Li-Na; Zhang, Bao-Yun; Xiao, Kang; Zhou, Wei; Chen, Cao; Zhang, Xiao-Mei; Tian, Chan; Gao, Chen; Wang, Jing; Han, Jun; Dong, Xiao-Ping

    2015-04-01

    Proteomics changes of brain tissues have been described in different neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. However, the brain proteomics of human prion disease remains less understood. In the study, the proteomics patterns of cortex and cerebellum of brain tissues of sporadic Creutzfeldt-Jakob disease, fatal familial insomnia, and G114V genetic CJD were analyzed with isobaric tags for relative and absolute quantitation combined with multidimensional liquid chromatography and MS analysis, with the brains from three normal individuals as controls. Global protein profiling, significant pathway, and functional categories were analyzed. In total, 2287 proteins were identified with quantitative information both in cortex and cerebellum regions. Cerebellum tissues appeared to contain more up- and down-regulated proteins (727 proteins) than cortex regions (312 proteins) of Creutzfeldt-Jakob disease, fatal familial insomnia, and G114V genetic CJD. Viral myocarditis, Parkinson's disease, Alzheimer's disease, lysosome, oxidative phosphorylation, protein export, and drug metabolism-cytochrome P450 were the most commonly affected pathways of the three kinds of diseases. Almost coincident biological functions were identified in the brain tissues of the three diseases. In all, data here demonstrate that the brain tissues of Creutzfeldt-Jakob disease, fatal familial insomnia, and G114V genetic CJD have obvious proteomics changes at their terminal stages, which show the similarities not only among human prion diseases but also with other neurodegeneration diseases. This is the first study to provide a reference proteome map for human prion diseases and will be helpful for future studies focused on potential biomarkers for the diagnosis and therapy of human prion diseases. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. Synthetic prions and other human neurodegenerative proteinopathies.

    Science.gov (United States)

    Le, Nhat Tran Thanh; Narkiewicz, Joanna; Aulić, Suzana; Salzano, Giulia; Tran, Hoa Thanh; Scaini, Denis; Moda, Fabio; Giachin, Gabriele; Legname, Giuseppe

    2015-09-02

    Transmissible spongiform encephalopathies (TSE) are a heterogeneous group of neurodegenerative disorders. The common feature of these diseases is the pathological conversion of the normal cellular prion protein (PrP(C)) into a β-structure-rich conformer-termed PrP(Sc). The latter can induce a self-perpetuating process leading to amplification and spreading of pathological protein assemblies. Much evidence suggests that PrP(Sc) itself is able to recruit and misfold PrP(C) into the pathological conformation. Recent data have shown that recombinant PrP(C) can be misfolded in vitro and the resulting synthetic conformers are able to induce the conversion of PrP(C) into PrP(Sc)in vivo. In this review we describe the state-of-the-art of the body of literature in this field. In addition, we describe a cell-based assay to test synthetic prions in cells, providing further evidence that synthetic amyloids are able to template conversion of PrP into prion inclusions. Studying prions might help to understand the pathological mechanisms governing other neurodegenerative diseases. Aggregation and deposition of misfolded proteins is a common feature of several neurodegenerative disorders, such as Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis and other disorders. Although the proteins implicated in each of these diseases differ, they share a common prion mechanism. Recombinant proteins are able to aggregate in vitro into β-rich amyloid fibrils, sharing some features of the aggregates found in the brain. Several studies have reported that intracerebral inoculation of synthetic aggregates lead to unique pathology, which spread progressively to distal brain regions and reduced survival time in animals. Here, we review the prion-like features of different proteins involved in neurodegenerative disorders, such as α-synuclein, superoxide dismutase-1, amyloid-β and tau. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. A Fluorescent Oligothiophene-Bis-Triazine ligand interacts with PrP fibrils and detects SDS-resistant oligomers in human prion diseases.

    Science.gov (United States)

    Imberdis, Thibaut; Ayrolles-Torro, Adeline; Duarte Rodrigues, Alysson; Torrent, Joan; Alvarez-Martinez, Maria Teresa; Kovacs, Gabor G; Verdier, Jean-Michel; Robitzer, Mike; Perrier, Véronique

    2016-01-26

    Prion diseases are characterized by the accumulation in the central nervous system of an abnormally folded isoform of the prion protein, named PrP(Sc). Aggregation of PrP(Sc) into oligomers and fibrils is critically involved in the pathogenesis of prion diseases. Oligomers are supposed to be the key neurotoxic agents in prion disease, so modulation of prion aggregation pathways with small molecules can be a valuable strategy for studying prion pathogenicity and for developing new diagnostic and therapeutic approaches. We previously identified thienyl pyrimidine compounds that induce SDS-resistant PrP(Sc) (rSDS-PrP(Sc)) oligomers in prion-infected samples. Due to the low effective doses of the thienyl pyrimidine hits, we synthesized a quaterthiophene-bis-triazine compound, called MR100 to better evaluate their diagnostic and therapeutic potentials. This molecule exhibits a powerful activity inducing rSDS-PrP(Sc) oligomers at nanomolar concentrations in prion-infected cells. Fluorescence interaction studies of MR100 with mouse PrP fibrils showed substantial modification of the spectrum, and the interaction was confirmed in vitro by production of rSDS-oligomer species upon incubation of MR100 with fibrils in SDS-PAGE gel. We further explored whether MR100 compound has a potential to be used in the diagnosis of prion diseases. Our results showed that: (i) MR100 can detect rSDS-oligomers in prion-infected brain homogenates of various species, including human samples from CJD patients; (ii) A protocol, called "Rapid Centrifugation Assay" (RCA), was developed based on MR100 property of inducing rSDS-PrP(Sc) oligomers only in prion-infected samples, and avoiding the protease digestion step. RCA allows the detection of both PK-sensitive and PK-resistant PrP(Sc) species in rodents samples but also from patients with different CJD forms (sporadic and new variant); (iii) A correlation could be established between the amount of rSDS-PrP(Sc) oligomers revealed by MR100 and the

  2. The human prion diseases. A review with special emphasis on new variant CJD and comments on surveillance.

    LENUS (Irish Health Repository)

    Keohane, C

    2012-02-03

    The transmissible spongiform encephalopathies or prion diseases represent a new group of diseases with unique clinical and neuropathological features, the transmission of which is both genetic and infectious. The responsible agent is unconventional and appears to be largely composed of a glycoprotein, the prion protein PrP. This is normally present on different cells. In prion diseases, it becomes converted to the pathogenic form PrPres which is resistant to proteinase and accumulates within the brain and this process is accompanied by the development of spongiform change, gliosis and neuronal loss. The human prion diseases include Kuru a progressive cerebellar degeneration with late dementia affecting Fore tribes in New-Guinea, now almost extinct, regarded as being related to cannibalism. Creutzfeldt-Jakob disease is the more frequent human prion disease. Its incidence is approximately one case per million per year. Four variants are now recognized: sporadic, familial, iatrogenic and the new variant. The latter represents a distinct clinico-pathological entity. It is now widely accepted that it is due to the same agent responsible for Bovine Spongiform Encephalopathy in cattle. Gerstmann-Straussler-Scheinker disease is a very rare inherited disorder due to a number of different mutations in the PRP gene, characterized by abundant deposits of plaque PrPres in the cerebral grey matter. Fatal familial insomnia is another inherited disorder due to a mutation at codon 178 of the PRP gene associated with methionine on codon 129 of the mutant allele. The main neuropathological change is neuronal loss in the thalamus with little or no spongiosis and usually no PrPres deposition. Following the emergence of new variant CJD in 1996, surveillance of all forms of prion diseases has been now been actively introduced in many European nations in order to determine the true incidence and geographic distribution of these rare disorders in humans.

  3. Prions

    NARCIS (Netherlands)

    Zijderveld, van F.G.

    2007-01-01

    The report 'Zoonoses and Zoonotic Agents in Humans, Food, Animals and Feed in The Netherlands 2003 - 2006' is based on data that is reported annually to the European Commission, in accordance with the Directive 2003/99/EC on the monitoring of zoonoses and zoonotic agents. They are supplemented with

  4. Absence of Evidence for a Causal Link between Bovine Spongiform Encephalopathy Strain Variant L-BSE and Known Forms of Sporadic Creutzfeldt-Jakob Disease in Human PrP Transgenic Mice.

    Science.gov (United States)

    Jaumain, Emilie; Quadrio, Isabelle; Herzog, Laetitia; Reine, Fabienne; Rezaei, Human; Andréoletti, Olivier; Laude, Hubert; Perret-Liaudet, Armand; Haïk, Stéphane; Béringue, Vincent

    2016-12-01

    Prions are proteinaceous pathogens responsible for subacute spongiform encephalopathies in animals and humans. The prions responsible for bovine spongiform encephalopathy (BSE) are zoonotic agents, causing variant Creutzfeldt-Jakob disease (CJD) in humans. The transfer of prions between species is limited by a species barrier, which is thought to reflect structural incompatibilities between the host cellular prion protein (PrP C ) and the infecting pathological PrP assemblies (PrP Sc ) constituting the prion. A BSE strain variant, designated L-BSE and responsible for atypical, supposedly spontaneous forms of prion diseases in aged cattle, demonstrates zoonotic potential, as evidenced by its capacity to propagate more easily than classical BSE in transgenic mice expressing human PrP C and in nonhuman primates. In humanized mice, L-BSE propagates without any apparent species barrier and shares similar biochemical PrP Sc signatures with the CJD subtype designated MM2-cortical, thus opening the possibility that certain CJD cases classified as sporadic may actually originate from L-type BSE cross-transmission. To address this issue, we compared the biological properties of L-BSE and those of a panel of CJD subtypes representative of the human prion strain diversity using standard strain-typing criteria in human PrP transgenic mice. We found no evidence that L-BSE causes a known form of sporadic CJD. Since the quasi-extinction of classical BSE, atypical BSE forms are the sole BSE variants circulating in cattle worldwide. They are observed in rare cases of old cattle, making them difficult to detect. Extrapolation of our results suggests that L-BSE may propagate in humans as an unrecognized form of CJD, and we urge both the continued utilization of precautionary measures to eliminate these agents from the human food chain and active surveillance for CJD phenotypes in the general population. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  5. Amyloid- and FDG-PET in sporadic Creutzfeldt-Jakob disease: Correlation with pathological prion protein in neuropathology.

    Science.gov (United States)

    Matías-Guiu, Jordi A; Guerrero-Márquez, Carmen; Cabrera-Martín, María Nieves; Gómez-Pinedo, Ulises; Romeral, María; Mayo, Diego; Porta-Etessam, Jesús; Moreno-Ramos, Teresa; Carreras, José Luis; Matías-Guiu, Jorge

    2017-05-04

    The role of positron emission tomography (PET) in Creutzfeldt-Jakob disease is less defined than in other neurodegenerative diseases. We studied the correlation between the uptake of 18 F-florbetaben and 18 F-fluorodeoxyglucose with pathological prion protein deposition in histopathology in a case. A patient with 80 y old with a rapid neurological deterioration with a confirmed diagnosis of CJD was studied. PET and MRI studies were performed between 13-20 d before the death. A region of interest analysis was performed using Statistical Parametric Mapping. MRI showed atrophy with no other alterations. FDG-PET showed extensive areas of hypometabolism including left frontoparietal lobes as well as bilateral thalamus. Correlation between uptake of 18 F-florbetaben and pathological prion protein deposition was r = 0.786 (p < 0.05). Otherwise, correlation between uptake of 18 F-FDG and pathological prion protein was r = 0.357 (p = 0.385). Immunohistochemistry with β-amyloid did not show amyloid deposition or neuritic plaques. Our study supports the use of FDG-PET in the assessment of CJD. FDG-PET may be especially useful in cases of suspected CJD and negative MRI. Furthermore, this case report provides more evidence about the behavioral of amyloid tracers, and the possibility of a low-affinity binding to other non-amyloid proteins, such as the pathological prion protein, is discussed.

  6. Molecular dynamics study of the dominant-negative E219K polymorphism in human prion protein

    NARCIS (Netherlands)

    Jahandideh, Samad; Jamalan, Mostafa; Faridounnia, Maryam|info:eu-repo/dai/nl/338666923

    2015-01-01

    Human prion diseases are associated with misfolding or aggregation of the Human Prion Protein (HuPrP). Missense mutations in the HuPrP gene, contribute to conversion of HuPrP(C) to HuPrP(Sc) and amyloid formation. Based on our previous comprehensive study, three missense mutations, from two

  7. Sporadic Fatal Insomnia in an Adolescent

    Science.gov (United States)

    Blase, Jennifer L.; Cracco, Laura; Schonberger, Lawrence B.; Maddox, Ryan A.; Cohen, Yvonne; Cali, Ignazio

    2014-01-01

    The occurrence of sporadic prion disease among adolescents is extremely rare. A prion disease was confirmed in an adolescent with disease onset at 13 years of age. Genetic, neuropathologic, and biochemical analyses of the patient’s autopsy brain tissue were consistent with sporadic fatal insomnia, a type of sporadic prion disease. There was no evidence of an environmental source of infection, and this patient represents the youngest documented case of sporadic prion disease. Although rare, a prion disease diagnosis should not be discounted in adolescents exhibiting neurologic signs. Brain tissue testing is necessary for disease confirmation and is particularly beneficial in cases with an unusual clinical presentation. PMID:24488737

  8. Guinea Pig Prion Protein Supports Rapid Propagation of Bovine Spongiform Encephalopathy and Variant Creutzfeldt-Jakob Disease Prions.

    Science.gov (United States)

    Watts, Joel C; Giles, Kurt; Saltzberg, Daniel J; Dugger, Brittany N; Patel, Smita; Oehler, Abby; Bhardwaj, Sumita; Sali, Andrej; Prusiner, Stanley B

    2016-11-01

    The biochemical and neuropathological properties of bovine spongiform encephalopathy (BSE) and variant Creutzfeldt-Jakob disease (vCJD) prions are faithfully maintained upon transmission to guinea pigs. However, primary and secondary transmissions of BSE and vCJD in guinea pigs result in long incubation periods of ∼450 and ∼350 days, respectively. To determine if the incubation periods of BSE and vCJD prions could be shortened, we generated transgenic (Tg) mice expressing guinea pig prion protein (GPPrP). Inoculation of Tg(GPPrP) mice with BSE and vCJD prions resulted in mean incubation periods of 210 and 199 days, respectively, which shortened to 137 and 122 days upon serial transmission. In contrast, three different isolates of sporadic CJD prions failed to transmit disease to Tg(GPPrP) mice. Many of the strain-specified biochemical and neuropathological properties of BSE and vCJD prions, including the presence of type 2 protease-resistant PrP Sc , were preserved upon propagation in Tg(GPPrP) mice. Structural modeling revealed that two residues near the N-terminal region of α-helix 1 in GPPrP might mediate its susceptibility to BSE and vCJD prions. Our results demonstrate that expression of GPPrP in Tg mice supports the rapid propagation of BSE and vCJD prions and suggest that Tg(GPPrP) mice may serve as a useful paradigm for bioassaying these prion isolates. Variant Creutzfeldt-Jakob disease (vCJD) and bovine spongiform encephalopathy (BSE) prions are two of the prion strains most relevant to human health. However, propagating these strains in mice expressing human or bovine prion protein has been difficult because of prolonged incubation periods or inefficient transmission. Here, we show that transgenic mice expressing guinea pig prion protein are fully susceptible to vCJD and BSE prions but not to sporadic CJD prions. Our results suggest that the guinea pig prion protein is a better, more rapid substrate than either bovine or human prion protein for

  9. Genetic human prion disease modelled in PrP transgenic Drosophila.

    Science.gov (United States)

    Thackray, Alana M; Cardova, Alzbeta; Wolf, Hanna; Pradl, Lydia; Vorberg, Ina; Jackson, Walker S; Bujdoso, Raymond

    2017-09-20

    Inherited human prion diseases, such as fatal familial insomnia (FFI) and familial Creutzfeldt-Jakob disease (fCJD), are associated with autosomal dominant mutations in the human prion protein gene PRNP and accumulation of PrP Sc , an abnormal isomer of the normal host protein PrP C , in the brain of affected individuals. PrP Sc is the principal component of the transmissible neurotoxic prion agent. It is important to identify molecular pathways and cellular processes that regulate prion formation and prion-induced neurotoxicity. This will allow identification of possible therapeutic interventions for individuals with, or at risk from, genetic human prion disease. Increasingly, Drosophila has been used to model human neurodegenerative disease. An important unanswered question is whether genetic prion disease with concomitant spontaneous prion formation can be modelled in Drosophila We have used pUAST/PhiC31-mediated site-directed mutagenesis to generate Drosophila transgenic for murine or hamster PrP (prion protein) that carry single-codon mutations associated with genetic human prion disease. Mouse or hamster PrP harbouring an FFI (D178N) or fCJD (E200K) mutation showed mild Proteinase K resistance when expressed in Drosophila Adult Drosophila transgenic for FFI or fCJD variants of mouse or hamster PrP displayed a spontaneous decline in locomotor ability that increased in severity as the flies aged. Significantly, this mutant PrP-mediated neurotoxic fly phenotype was transferable to recipient Drosophila that expressed the wild-type form of the transgene. Collectively, our novel data are indicative of the spontaneous formation of a PrP-dependent neurotoxic phenotype in FFI- or CJD-PrP transgenic Drosophila and show that inherited human prion disease can be modelled in this invertebrate host. © 2017 The Author(s).

  10. Inactivation of animal and human prions by hydrogen peroxide gas plasma sterilization.

    Science.gov (United States)

    Rogez-Kreuz, C; Yousfi, R; Soufflet, C; Quadrio, I; Yan, Z-X; Huyot, V; Aubenque, C; Destrez, P; Roth, K; Roberts, C; Favero, M; Clayette, P

    2009-08-01

    Prions cause various transmissible spongiform encephalopathies. They are highly resistant to the chemical and physical decontamination and sterilization procedures routinely used in healthcare facilities. The decontamination procedures recommended for the inactivation of prions are often incompatible with the materials used in medical devices. In this study, we evaluated the use of low-temperature hydrogen peroxide gas plasma sterilization systems and other instrument-processing procedures for inactivating human and animal prions. We provide new data concerning the efficacy of hydrogen peroxide against prions from in vitro or in vivo tests, focusing on the following: the efficiency of hydrogen peroxide sterilization and possible interactions with enzymatic or alkaline detergents, differences in the efficiency of this treatment against different prion strains, and the influence of contaminating lipids. We found that gaseous hydrogen peroxide decreased the infectivity of prions and/or the level of the protease-resistant form of the prion protein on different surface materials. However, the efficiency of this treatment depended strongly on the concentration of hydrogen peroxide and the delivery system used in medical devices, because these effects were more pronounced for the new generation of Sterrad technology. The Sterrad NX sterilizer is 100% efficient (0% transmission and no protease-resistant form of the prion protein signal detected on the surface of the material for the mouse-adapted bovine spongiform encephalopathy 6PB1 strain and a variant Creutzfeldt-Jakob disease strain). Thus, gaseous or vaporized hydrogen peroxide efficiently inactivates prions on the surfaces of medical devices.

  11. Inherited prion disease A117V is not simply a proteinopathy but produces prions transmissible to transgenic mice expressing homologous prion protein.

    Directory of Open Access Journals (Sweden)

    Emmanuel A Asante

    Full Text Available Prions are infectious agents causing fatal neurodegenerative diseases of humans and animals. In humans, these have sporadic, acquired and inherited aetiologies. The inherited prion diseases are caused by one of over 30 coding mutations in the human prion protein (PrP gene (PRNP and many of these generate infectious prions as evidenced by their experimental transmissibility by inoculation to laboratory animals. However, some, and in particular an extensively studied type of Gerstmann-Sträussler-Scheinker syndrome (GSS caused by a PRNP A117V mutation, are thought not to generate infectious prions and instead constitute prion proteinopathies with a quite distinct pathogenetic mechanism. Multiple attempts to transmit A117V GSS have been unsuccessful and typical protease-resistant PrP (PrP(Sc, pathognomonic of prion disease, is not detected in brain. Pathogenesis is instead attributed to production of an aberrant topological form of PrP, C-terminal transmembrane PrP ((CtmPrP. Barriers to transmission of prion strains from one species to another appear to relate to structural compatibility of PrP in host and inoculum and we have therefore produced transgenic mice expressing human 117V PrP. We found that brain tissue from GSS A117V patients did transmit disease to these mice and both the neuropathological features of prion disease and presence of PrP(Sc was demonstrated in the brains of recipient transgenic mice. This PrP(Sc rapidly degraded during laboratory analysis, suggesting that the difficulty in its detection in patients with GSS A117V could relate to post-mortem proteolysis. We conclude that GSS A117V is indeed a prion disease although the relative contributions of (CtmPrP and prion propagation in neurodegeneration and their pathogenetic interaction remains to be established.

  12. Inherited prion disease A117V is not simply a proteinopathy but produces prions transmissible to transgenic mice expressing homologous prion protein.

    Science.gov (United States)

    Asante, Emmanuel A; Linehan, Jacqueline M; Smidak, Michelle; Tomlinson, Andrew; Grimshaw, Andrew; Jeelani, Asif; Jakubcova, Tatiana; Hamdan, Shyma; Powell, Caroline; Brandner, Sebastian; Wadsworth, Jonathan D F; Collinge, John

    2013-01-01

    Prions are infectious agents causing fatal neurodegenerative diseases of humans and animals. In humans, these have sporadic, acquired and inherited aetiologies. The inherited prion diseases are caused by one of over 30 coding mutations in the human prion protein (PrP) gene (PRNP) and many of these generate infectious prions as evidenced by their experimental transmissibility by inoculation to laboratory animals. However, some, and in particular an extensively studied type of Gerstmann-Sträussler-Scheinker syndrome (GSS) caused by a PRNP A117V mutation, are thought not to generate infectious prions and instead constitute prion proteinopathies with a quite distinct pathogenetic mechanism. Multiple attempts to transmit A117V GSS have been unsuccessful and typical protease-resistant PrP (PrP(Sc)), pathognomonic of prion disease, is not detected in brain. Pathogenesis is instead attributed to production of an aberrant topological form of PrP, C-terminal transmembrane PrP ((Ctm)PrP). Barriers to transmission of prion strains from one species to another appear to relate to structural compatibility of PrP in host and inoculum and we have therefore produced transgenic mice expressing human 117V PrP. We found that brain tissue from GSS A117V patients did transmit disease to these mice and both the neuropathological features of prion disease and presence of PrP(Sc) was demonstrated in the brains of recipient transgenic mice. This PrP(Sc) rapidly degraded during laboratory analysis, suggesting that the difficulty in its detection in patients with GSS A117V could relate to post-mortem proteolysis. We conclude that GSS A117V is indeed a prion disease although the relative contributions of (Ctm)PrP and prion propagation in neurodegeneration and their pathogenetic interaction remains to be established.

  13. Characterization of Variant Creutzfeldt-Jakob Disease Prions in Prion Protein-humanized Mice Carrying Distinct Codon 129 Genotypes*

    Science.gov (United States)

    Takeuchi, Atsuko; Kobayashi, Atsushi; Ironside, James W.; Mohri, Shirou; Kitamoto, Tetsuyuki

    2013-01-01

    To date, all clinical variant Creutzfeldt-Jakob disease (vCJD) patients are homozygous for methionine at polymorphic codon 129 (129M/M) of the prion protein (PrP) gene. However, the appearance of asymptomatic secondary vCJD infection in individuals with a PRNP codon 129 genotype other than M/M and transmission studies using animal models have raised the concern that all humans might be susceptible to vCJD prions, especially via secondary infection. To reevaluate this possibility and to analyze in detail the transmission properties of vCJD prions to transgenic animals carrying distinct codon 129 genotype, we performed intracerebral inoculation of vCJD prions to humanized knock-in mice carrying all possible codon 129 genotypes (129M/M, 129M/V, or 129V/V). All humanized knock-in mouse lines were susceptible to vCJD infection, although the attack rate gradually decreased from 129M/M to 129M/V and to 129V/V. The amount of PrP deposition including florid/amyloid plaques in the brain also gradually decreased from 129M/M to 129M/V and to 129V/V. The biochemical properties of protease-resistant abnormal PrP in the brain and transmissibility of these humanized mouse-passaged vCJD prions upon subpassage into knock-in mice expressing bovine PrP were not affected by the codon 129 genotype. These results indicate that individuals with the 129V/V genotype may be more susceptible to secondary vCJD infection than expected and may lack the neuropathological characteristics observed in vCJD patients with the 129M/M genotype. Besides the molecular typing of protease-resistant PrP in the brain, transmission studies using knock-in mice carrying bovine PrP may aid the differential diagnosis of secondary vCJD infection, especially in individuals with the 129V/V genotype. PMID:23792955

  14. Characterization of variant Creutzfeldt-Jakob disease prions in prion protein-humanized mice carrying distinct codon 129 genotypes.

    Science.gov (United States)

    Takeuchi, Atsuko; Kobayashi, Atsushi; Ironside, James W; Mohri, Shirou; Kitamoto, Tetsuyuki

    2013-07-26

    To date, all clinical variant Creutzfeldt-Jakob disease (vCJD) patients are homozygous for methionine at polymorphic codon 129 (129M/M) of the prion protein (PrP) gene. However, the appearance of asymptomatic secondary vCJD infection in individuals with a PRNP codon 129 genotype other than M/M and transmission studies using animal models have raised the concern that all humans might be susceptible to vCJD prions, especially via secondary infection. To reevaluate this possibility and to analyze in detail the transmission properties of vCJD prions to transgenic animals carrying distinct codon 129 genotype, we performed intracerebral inoculation of vCJD prions to humanized knock-in mice carrying all possible codon 129 genotypes (129M/M, 129M/V, or 129V/V). All humanized knock-in mouse lines were susceptible to vCJD infection, although the attack rate gradually decreased from 129M/M to 129M/V and to 129V/V. The amount of PrP deposition including florid/amyloid plaques in the brain also gradually decreased from 129M/M to 129M/V and to 129V/V. The biochemical properties of protease-resistant abnormal PrP in the brain and transmissibility of these humanized mouse-passaged vCJD prions upon subpassage into knock-in mice expressing bovine PrP were not affected by the codon 129 genotype. These results indicate that individuals with the 129V/V genotype may be more susceptible to secondary vCJD infection than expected and may lack the neuropathological characteristics observed in vCJD patients with the 129M/M genotype. Besides the molecular typing of protease-resistant PrP in the brain, transmission studies using knock-in mice carrying bovine PrP may aid the differential diagnosis of secondary vCJD infection, especially in individuals with the 129V/V genotype.

  15. Spontaneous generation of rapidly transmissible prions in transgenic mice expressing wild-type bank vole prion protein.

    Science.gov (United States)

    Watts, Joel C; Giles, Kurt; Stöhr, Jan; Oehler, Abby; Bhardwaj, Sumita; Grillo, Sunny K; Patel, Smita; DeArmond, Stephen J; Prusiner, Stanley B

    2012-02-28

    Currently, there are no animal models of the most common human prion disorder, sporadic Creutzfeldt-Jakob disease (CJD), in which prions are formed spontaneously from wild-type (WT) prion protein (PrP). Interestingly, bank voles (BV) exhibit an unprecedented promiscuity for diverse prion isolates, arguing that bank vole PrP (BVPrP) may be inherently prone to adopting misfolded conformations. Therefore, we constructed transgenic (Tg) mice expressing WT BVPrP. Tg(BVPrP) mice developed spontaneous CNS dysfunction between 108 and 340 d of age and recapitulated the hallmarks of prion disease, including spongiform degeneration, pronounced astrogliosis, and deposition of alternatively folded PrP in the brain. Brain homogenates of ill Tg(BVPrP) mice transmitted disease to Tg(BVPrP) mice in ∼35 d, to Tg mice overexpressing mouse PrP in under 100 d, and to WT mice in ∼185 d. Our studies demonstrate experimentally that WT PrP can spontaneously form infectious prions in vivo. Thus, Tg(BVPrP) mice may be useful for studying the spontaneous formation of prions, and thus may provide insight into the etiology of sporadic CJD.

  16. Generic amyloidogenicity of mammalian prion proteins from species susceptible and resistant to prions.

    Science.gov (United States)

    Nyström, Sofie; Hammarström, Per

    2015-05-11

    Prion diseases are lethal, infectious diseases associated with prion protein (PrP) misfolding. A large number of mammals are susceptible to both sporadic and acquired prion diseases. Although PrP is highly conserved and ubiquitously expressed in all mammals, not all species exhibit prion disease. By employing full length recombinant PrP from five known prion susceptible species (human, cattle, cat, mouse and hamster) and two species considered to be prion resistant (pig and dog) the amyloidogenicity of these PrPs has been delineated. All the mammalian PrPs, even from resistant species, were swiftly converted from the native state to amyloid-like structure when subjected to a native condition conversion assay. The PrPs displayed amyloidotypic tinctorial and ultrastructural hallmarks. Self-seeded conversion of the PrPs displayed significantly decreased lag phases demonstrating that nucleation dependent polymerization is a dominating mechanism in the fibrillation process. Fibrils from Aβ1-40, Aβ1-42, Lysozyme, Insulin and Transthyretin did not accelerate conversion of HuPrP whereas fibrils from HuPrP90-231 and HuPrP121-231 as well as full length PrPs of all PrPs efficiently seeded conversion showing specificity of the assay requiring the C-terminal PrP sequence. Our findings have implications for PrP misfolding and could have ramifications in the context of prion resistant species and silent carriers.

  17. Genetics Home Reference: prion disease

    Science.gov (United States)

    ... which have overlapping signs and symptoms, include familial Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), and fatal ... Sc . Sporadic forms of prion disease include sporadic Creutzfeldt-Jakob disease (sCJD), sporadic fatal insomnia (sFI), and variably protease- ...

  18. The expanding universe of prion diseases.

    Directory of Open Access Journals (Sweden)

    2006-03-01

    Full Text Available Prions cause fatal and transmissible neurodegenerative disease. These etiological infectious agents are formed in greater part from a misfolded cell-surface protein called PrP(C. Several mammalian species are affected by the diseases, and in the case of "mad cow disease" (BSE the agent has a tropism for humans, with negative consequences for agribusiness and public health. Unfortunately, the known universe of prion diseases is expanding. At least four novel prion diseases-including human diseases variant Creutzfeldt-Jakob disease (vCJD and sporadic fatal insomnia (sFI, bovine amyloidotic spongiform encephalopathy (BASE, and Nor98 of sheep-have been identified in the last ten years, and chronic wasting disease (CWD of North American deer (Odocoileus Specis and Rocky Mountain elk (Cervus elaphus nelsoni is undergoing a dramatic spread across North America. While amplification (BSE and dissemination (CWD, commercial sourcing of cervids from the wild and movement of farmed elk can be attributed to human activity, the origins of emergent prion diseases cannot always be laid at the door of humankind. Instead, the continued appearance of new outbreaks in the form of "sporadic" disease may be an inevitable outcome in a situation where the replicating pathogen is host-encoded.

  19. The expanding universe of prion diseases.

    Directory of Open Access Journals (Sweden)

    Joel C Watts

    2006-03-01

    Full Text Available Prions cause fatal and transmissible neurodegenerative disease. These etiological infectious agents are formed in greater part from a misfolded cell-surface protein called PrP(C. Several mammalian species are affected by the diseases, and in the case of "mad cow disease" (BSE the agent has a tropism for humans, with negative consequences for agribusiness and public health. Unfortunately, the known universe of prion diseases is expanding. At least four novel prion diseases--including human diseases variant Creutzfeldt-Jakob disease (vCJD and sporadic fatal insomnia (sFI, bovine amyloidotic spongiform encephalopathy (BASE, and Nor98 of sheep--have been identified in the last ten years, and chronic wasting disease (CWD of North American deer (Odocoileus Specis and Rocky Mountain elk (Cervus elaphus nelsoni is undergoing a dramatic spread across North America. While amplification (BSE and dissemination (CWD, commercial sourcing of cervids from the wild and movement of farmed elk can be attributed to human activity, the origins of emergent prion diseases cannot always be laid at the door of humankind. Instead, the continued appearance of new outbreaks in the form of "sporadic" disease may be an inevitable outcome in a situation where the replicating pathogen is host-encoded.

  20. The expanding universe of prion diseases.

    Science.gov (United States)

    Watts, Joel C; Balachandran, Aru; Westaway, David

    2006-03-01

    Prions cause fatal and transmissible neurodegenerative disease. These etiological infectious agents are formed in greater part from a misfolded cell-surface protein called PrP(C). Several mammalian species are affected by the diseases, and in the case of "mad cow disease" (BSE) the agent has a tropism for humans, with negative consequences for agribusiness and public health. Unfortunately, the known universe of prion diseases is expanding. At least four novel prion diseases--including human diseases variant Creutzfeldt-Jakob disease (vCJD) and sporadic fatal insomnia (sFI), bovine amyloidotic spongiform encephalopathy (BASE), and Nor98 of sheep--have been identified in the last ten years, and chronic wasting disease (CWD) of North American deer (Odocoileus Specis) and Rocky Mountain elk (Cervus elaphus nelsoni) is undergoing a dramatic spread across North America. While amplification (BSE) and dissemination (CWD, commercial sourcing of cervids from the wild and movement of farmed elk) can be attributed to human activity, the origins of emergent prion diseases cannot always be laid at the door of humankind. Instead, the continued appearance of new outbreaks in the form of "sporadic" disease may be an inevitable outcome in a situation where the replicating pathogen is host-encoded.

  1. A novel seven-octapeptide repeat insertion in the prion protein gene (PRNP) in a Dutch pedigree with Gerstmann-Sträussler-Scheinker disease phenotype: comparison with similar cases from the literature

    NARCIS (Netherlands)

    Jansen, Casper; Voet, Willem; Head, Mark W.; Parchi, Piero; Yull, Helen; Verrips, Aad; Wesseling, Pieter; Meulstee, Jan; Baas, Frank; van Gool, Willem A.; Ironside, James W.; Rozemuller, Annemieke J. M.

    2011-01-01

    Human prion diseases can be sporadic, inherited or acquired by infection and show considerable phenotypic heterogeneity. We describe the clinical, histopathological and pathological prion protein (PrP(Sc)) characteristics of a Dutch family with a novel 7-octapeptide repeat insertion (7-OPRI) in

  2. Early detection of abnormal prion protein in genetic human prion diseases now possible using real-time QUIC assay.

    Directory of Open Access Journals (Sweden)

    Kazunori Sano

    Full Text Available INTRODUCTION: The definitive diagnosis of genetic prion diseases (gPrD requires pathological confirmation. To date, diagnosis has relied upon the finding of the biomarkers 14-3-3 protein and total tau (t-tau protein in the cerebrospinal fluid (CSF, but many researchers have reported that these markers are not sufficiently elevated in gPrD, especially in Gerstmann-Sträussler-Scheinker syndrome (GSS. We recently developed a new in vitro amplification technology, designated "real-time quaking-induced conversion (RT-QUIC", to detect the abnormal form of prion protein in CSF from sporadic Creutzfeldt-Jakob disease (sCJD patients. In the present study, we aimed to investigate the presence of biomarkers and evaluate RT-QUIC assay in patients with gPrD, as the utility of RT-QUIC as a diagnostic tool in gPrD has yet to be determined. METHOD/PRINCIPAL FINDINGS: 56 CSF samples were obtained from gPrD patients, including 20 cases of GSS with P102L mutation, 12 cases of fatal familial insomnia (FFI; D178N, and 24 cases of genetic CJD (gCJD, comprising 22 cases with E200K mutation and 2 with V203I mutation. We subjected all CSF samples to RT-QUIC assay, analyzed 14-3-3 protein by Western blotting, and measured t-tau protein using an ELISA kit. The detection sensitivities of RT-QUIC were as follows: GSS (78%, FFI (100%, gCJD E200K (87%, and gCJD V203I (100%. On the other hand the detection sensitivities of biomarkers were considerably lower: GSS (11%, FFI (0%, gCJD E200K (73%, and gCJD V203I (67%. Thus, RT-QUIC had a much higher detection sensitivity compared with testing for biomarkers, especially in patients with GSS and FFI. CONCLUSION/SIGNIFICANCE: RT-QUIC assay is more sensitive than testing for biomarkers in gPrD patients. RT-QUIC method would thus be useful as a diagnostic tool when the patient or the patient's family does not agree to genetic testing, or to confirm the diagnosis in the presence of a positive result for genetic testing.

  3. Region-specific protein misfolding cyclic amplification reproduces brain tropism of prion strains.

    Science.gov (United States)

    Privat, Nicolas; Levavasseur, Etienne; Yildirim, Serfildan; Hannaoui, Samia; Brandel, Jean-Philippe; Laplanche, Jean-Louis; Béringue, Vincent; Seilhean, Danielle; Haïk, Stéphane

    2017-10-06

    Human prion diseases such as Creutzfeldt-Jakob disease are transmissible brain proteinopathies, characterized by the accumulation of a misfolded isoform of the host cellular prion protein (PrP) in the brain. According to the prion model, prions are defined as proteinaceous infectious particles composed solely of this abnormal isoform of PrP (PrP Sc ). Even in the absence of genetic material, various prion strains can be propagated in experimental models. They can be distinguished by the pattern of disease they produce and especially by the localization of PrP Sc deposits within the brain and the spongiform lesions they induce. The mechanisms involved in this strain-specific targeting of distinct brain regions still are a fundamental, unresolved question in prion research. To address this question, we exploited a prion conversion in vitro assay, protein misfolding cyclic amplification (PMCA), by using experimental scrapie and human prion strains as seeds and specific brain regions from mice and humans as substrates. We show here that region-specific PMCA in part reproduces the specific brain targeting observed in experimental, acquired, and sporadic Creutzfeldt-Jakob diseases. Furthermore, we provide evidence that, in addition to cellular prion protein, other region- and species-specific molecular factors influence the strain-dependent prion conversion process. This important step toward understanding prion strain propagation in the human brain may impact research on the molecular factors involved in protein misfolding and the development of ultrasensitive methods for diagnosing prion disease. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Prion diseases: immunotargets and therapy

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    Burchell JT

    2016-06-01

    Full Text Available Jennifer T Burchell, Peter K Panegyres Neurodegenerative Disorders Research Pty Ltd, West Perth, Western Australia, Australia Abstract: Transmissible spongiform encephathalopathies or prion diseases are a group of neurological disorders characterized by neuronal loss, spongiform degeneration, and activation of astrocytes or microglia. These diseases affect humans and animals with an extremely high prevalence in some species such as deer and elk in North America. Although rare in humans, they result in a devastatingly swift neurological progression with dementia and ataxia. Patients usually die within a year of diagnosis. Prion diseases are familial, sporadic, iatrogenic, or transmissible. Human prion diseases include Kuru, sporadic, iatrogenic, and familial forms of Creutzfeldt–Jakob disease, variant Creutzfeldt–Jakob disease, Gerstmann–Sträussler–Scheinker disease, and fatal familial insomnia. The causative agent is a misfolded version of the physiological prion protein called PrPSc in the brain. There are a number of therapeutic options currently under investigation. A number of small molecules have had some success in delaying disease progression in animal models and mixed results in clinical trials, including pentosan polysulfate, quinacrine, and amphotericin B. More promisingly, immunotherapy has reported success in vitro and in vivo in animal studies and clinical trials. The three main branches of immunotherapy research are focus on antibody vaccines, dendritic cell vaccines, and adoptive transfer of physiological prion protein-specific CD4+ T-lymphocytes. Vaccines utilizing antibodies generally target disease-specific epitopes that are only exposed in the misfolded PrPSc conformation. Vaccines utilizing antigen-loaded dendritic cell have the ability to bypass immune tolerance and prime CD4+ cells to initiate an immune response. Adoptive transfer of CD4+ T-cells is another promising target as this cell type can orchestrate the

  5. A comparative molecular dynamics study on thermostability of human and chicken prion proteins

    International Nuclear Information System (INIS)

    Ji, Hong-Fang; Zhang, Hong-Yu

    2007-01-01

    To compare the thermostabilities of human and chicken normal cellular prion proteins (HuPrP C and CkPrP C ), molecular dynamics (MD) simulations were performed for both proteins at an ensemble level (10 parallel simulations at 400 K and 5 parallel simulations at 300 K as a control). It is found that the thermostability of HuPrP C is comparable with that of CkPrP C , which implicates that the non-occurrence of prion diseases in non-mammals cannot be completely attributed to the thermodynamic properties of non-mammalian PrP C

  6. Generation of human scFvs antibodies recognizing a prion protein epitope expressed on the surface of human lymphoblastoid cells

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    Imperiale Valentina

    2007-07-01

    Full Text Available Abstract Background A hallmark of prion disease is the transformation of normal cellular prion protein (PrPc into an infectious disease-associated isoform, (PrPsc. Anti-prion protein monoclonal antibodies are invaluable for structure-function studies of PrP molecules. Furthermore recent in vitro and in vivo studies indicate that anti-PrP monoclonal antibodies can prevent the incorporation of PrPc into propagating prions. In the present article, we show two new human phage antibodies, isolated on recombinant hamster prion protein (rHaPrP. Results We adopted an antibody phage display strategy to isolate specific human antibodies directed towards rHaPrP which has been used as a bait for panning the synthetic ETH-2 antibody phage library. Two phage antibodies clones named MA3.B4 and MA3.G3 were isolated and characterized under genetic biochemical and immunocytochemical aspects. The clones were found to recognize the prion protein in ELISA studies. In flow-cytometry studies, these human single chain Fragment variable (scFv phage-antibodies show a well defined pattern of reactivity on human lymphoblastoid and myeloid cells. Conclusion Sequence analysis of the gene encoding for the antibody fragments and antigen recognition patterns determined by flow-cytometry analysis indicate that the isolated scFvs recognize novel epitopes in the PrPc molecule. These new anti PrPc human antibodies are unique reagents for prion protein detection and may represent a biologic platform to develop new reagents to treat PrPsc associated disease.

  7. Porcine prion protein amyloid.

    Science.gov (United States)

    Hammarström, Per; Nyström, Sofie

    2015-01-01

    Mammalian prions are composed of misfolded aggregated prion protein (PrP) with amyloid-like features. Prions are zoonotic disease agents that infect a wide variety of mammalian species including humans. Mammals and by-products thereof which are frequently encountered in daily life are most important for human health. It is established that bovine prions (BSE) can infect humans while there is no such evidence for any other prion susceptible species in the human food chain (sheep, goat, elk, deer) and largely prion resistant species (pig) or susceptible and resistant pets (cat and dogs, respectively). PrPs from these species have been characterized using biochemistry, biophysics and neurobiology. Recently we studied PrPs from several mammals in vitro and found evidence for generic amyloidogenicity as well as cross-seeding fibril formation activity of all PrPs on the human PrP sequence regardless if the original species was resistant or susceptible to prion disease. Porcine PrP amyloidogenicity was among the studied. Experimentally inoculated pigs as well as transgenic mouse lines overexpressing porcine PrP have, in the past, been used to investigate the possibility of prion transmission in pigs. The pig is a species with extraordinarily wide use within human daily life with over a billion pigs harvested for human consumption each year. Here we discuss the possibility that the largely prion disease resistant pig can be a clinically silent carrier of replicating prions.

  8. Small protease sensitive oligomers of PrPSc in distinct human prions determine conversion rate of PrP(C.

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    Chae Kim

    Full Text Available The mammalian prions replicate by converting cellular prion protein (PrP(C into pathogenic conformational isoform (PrP(Sc. Variations in prions, which cause different disease phenotypes, are referred to as strains. The mechanism of high-fidelity replication of prion strains in the absence of nucleic acid remains unsolved. We investigated the impact of different conformational characteristics of PrP(Sc on conversion of PrP(C in vitro using PrP(Sc seeds from the most frequent human prion disease worldwide, the Creutzfeldt-Jakob disease (sCJD. The conversion potency of a broad spectrum of distinct sCJD prions was governed by the level, conformation, and stability of small oligomers of the protease-sensitive (s PrP(Sc. The smallest most potent prions present in sCJD brains were composed only of∼20 monomers of PrP(Sc. The tight correlation between conversion potency of small oligomers of human sPrP(Sc observed in vitro and duration of the disease suggests that sPrP(Sc conformers are an important determinant of prion strain characteristics that control the progression rate of the disease.

  9. Prion Diseases

    Science.gov (United States)

    ... with facebook share with twitter share with linkedin Prion Diseases Prion diseases are a related group of ... deer and elk. Why Is the Study of Prion Diseases a Priority for NIAID? Much about TSE ...

  10. Animal models for testing anti-prion drugs.

    Science.gov (United States)

    Fernández-Borges, Natalia; Elezgarai, Saioa R; Eraña, Hasier; Castilla, Joaquín

    2013-01-01

    Prion diseases belong to a group of fatal infectious diseases with no effective therapies available. Throughout the last 35 years, less than 50 different drugs have been tested in different experimental animal models without hopeful results. An important limitation when searching for new drugs is the existence of appropriate models of the disease. The three different possible origins of prion diseases require the existence of different animal models for testing anti-prion compounds. Wild type, over-expressing transgenic mice and other more sophisticated animal models have been used to evaluate a diversity of compounds which some of them were previously tested in different in vitro experimental models. The complexity of prion diseases will require more pre-screening studies, reliable sporadic (or spontaneous) animal models and accurate chemical modifications of the selected compounds before having an effective therapy against human prion diseases. This review is intended to put on display the more relevant animal models that have been used in the search of new antiprion therapies and describe some possible procedures when handling chemical compounds presumed to have anti-prion activity prior to testing them in animal models.

  11. Yeast prions: structure, biology, and prion-handling systems.

    Science.gov (United States)

    Wickner, Reed B; Shewmaker, Frank P; Bateman, David A; Edskes, Herman K; Gorkovskiy, Anton; Dayani, Yaron; Bezsonov, Evgeny E

    2015-03-01

    A prion is an infectious protein horizontally transmitting a disease or trait without a required nucleic acid. Yeast and fungal prions are nonchromosomal genes composed of protein, generally an altered form of a protein that catalyzes the same alteration of the protein. Yeast prions are thus transmitted both vertically (as genes composed of protein) and horizontally (as infectious proteins, or prions). Formation of amyloids (linear ordered β-sheet-rich protein aggregates with β-strands perpendicular to the long axis of the filament) underlies most yeast and fungal prions, and a single prion protein can have any of several distinct self-propagating amyloid forms with different biological properties (prion variants). Here we review the mechanism of faithful templating of protein conformation, the biological roles of these prions, and their interactions with cellular chaperones, the Btn2 and Cur1 aggregate-handling systems, and other cellular factors governing prion generation and propagation. Human amyloidoses include the PrP-based prion conditions and many other, more common amyloid-based diseases, several of which show prion-like features. Yeast prions increasingly are serving as models for the understanding and treatment of many mammalian amyloidoses. Patients with different clinical pictures of the same amyloidosis may be the equivalent of yeasts with different prion variants. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. Regulation of human cerebrospinal fluid malate dehydrogenase 1 in sporadic Creutzfeldt-Jakob disease patients.

    Science.gov (United States)

    Schmitz, Matthias; Llorens, Franc; Pracht, Alexander; Thom, Tobias; Correia, Ângela; Zafar, Saima; Ferrer, Isidre; Zerr, Inga

    2016-11-14

    The identification of reliable diagnostic biomarkers in differential diagnosis of neurodegenerative diseases is an ongoing topic. A previous two-dimensional proteomic study on cerebrospinal fluid (CSF) revealed an elevated level of an enzyme, mitochondrial malate dehydrogenase 1 (MDH1), in sporadic Creutzfeldt-Jakob disease (sCJD) patients. Here, we could demonstrate the expression of MDH1 in neurons as well as in the neuropil. Its levels are lower in sCJD brains than in control brains. An examination of CSF-MDH1 in sCJD patients by ELISA revealed a significant elevation of CSF-MDH1 levels in sCJD patients (independently from the PRNP codon 129 MV genotype or the prion protein scrapie (PrP Sc ) type) in comparison to controls. In combination with total tau (tau), CSF-MDH1 detection exhibited a high diagnostic accuracy for sCJD diagnosis with a sensitivity of 97.5% and a specificity of 95.6%. A correlation study of MDH1 level in CSF with other neurodegenerative marker proteins revealed a significant positive correlation between MDH1 concentration with tau, 14-3-3 and neuron specific enolase level. In conclusion, our study indicated the potential of MDH1 in combination with tau as an additional biomarker in sCJD improving diagnostic accuracy of tau markedly.

  13. Evidence that bank vole PrP is a universal acceptor for prions.

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    Joel C Watts

    2014-04-01

    Full Text Available Bank voles are uniquely susceptible to a wide range of prion strains isolated from many different species. To determine if this enhanced susceptibility to interspecies prion transmission is encoded within the sequence of the bank vole prion protein (BVPrP, we inoculated Tg(M109 and Tg(I109 mice, which express BVPrP containing either methionine or isoleucine at polymorphic codon 109, with 16 prion isolates from 8 different species: humans, cattle, elk, sheep, guinea pigs, hamsters, mice, and meadow voles. Efficient disease transmission was observed in both Tg(M109 and Tg(I109 mice. For instance, inoculation of the most common human prion strain, sporadic Creutzfeldt-Jakob disease (sCJD subtype MM1, into Tg(M109 mice gave incubation periods of ∼200 days that were shortened slightly on second passage. Chronic wasting disease prions exhibited an incubation time of ∼250 days, which shortened to ∼150 days upon second passage in Tg(M109 mice. Unexpectedly, bovine spongiform encephalopathy and variant CJD prions caused rapid neurological dysfunction in Tg(M109 mice upon second passage, with incubation periods of 64 and 40 days, respectively. Despite the rapid incubation periods, other strain-specified properties of many prion isolates--including the size of proteinase K-resistant PrPSc, the pattern of cerebral PrPSc deposition, and the conformational stability--were remarkably conserved upon serial passage in Tg(M109 mice. Our results demonstrate that expression of BVPrP is sufficient to engender enhanced susceptibility to a diverse range of prion isolates, suggesting that BVPrP may be a universal acceptor for prions.

  14. TDP-43 or FUS-induced misfolded human wild-type SOD1 can propagate intercellularly in a prion-like fashion.

    Science.gov (United States)

    Pokrishevsky, Edward; Grad, Leslie I; Cashman, Neil R

    2016-03-01

    Amyotrophic lateral sclerosis (ALS), which appears to spread through the neuroaxis in a spatiotemporally restricted manner, is linked to heritable mutations in genes encoding SOD1, TDP-43, FUS, C9ORF72, or can occur sporadically without recognized genetic mutations. Misfolded human wild-type (HuWt) SOD1 has been detected in both familial and sporadic ALS patients, despite mutations in SOD1 accounting for only 2% of total cases. We previously showed that accumulation of pathological TDP-43 or FUS coexist with misfolded HuWtSOD1 in patient motor neurons, and can trigger its misfolding in cultured cells. Here, we used immunocytochemistry and immunoprecipitation to demonstrate that TDP-43 or FUS-induced misfolded HuWtSOD1 can propagate from cell-to-cell via conditioned media, and seed cytotoxic misfolding of endogenous HuWtSOD1 in the recipient cells in a prion-like fashion. Knockdown of SOD1 using siRNA in recipient cells, or incubation of conditioned media with misfolded SOD1-specific antibodies, inhibits intercellular transmission, indicating that HuWtSOD1 is an obligate seed and substrate of propagated misfolding. In this system, intercellular spread of SOD1 misfolding is not accompanied by transmission of TDP-43 or FUS pathology. Our findings argue that pathological TDP-43 and FUS may exert motor neuron pathology in ALS through the initiation of propagated misfolding of SOD1.

  15. Antimicrobial Activity of Human Prion Protein Is Mediated by Its N-Terminal Region

    OpenAIRE

    Pasupuleti, Mukesh; Roupe, Markus; Rydeng?rd, Victoria; Surewicz, Krystyna; Surewicz, Witold K.; Chalupka, Anna; Malmsten, Martin; S?rensen, Ole E.; Schmidtchen, Artur

    2009-01-01

    BACKGROUND: Cellular prion-related protein (PrP(c)) is a cell-surface protein that is ubiquitously expressed in the human body. The multifunctionality of PrP(c), and presence of an exposed cationic and heparin-binding N-terminus, a feature characterizing many antimicrobial peptides, made us hypothesize that PrP(c) could exert antimicrobial activity. METHODOLOGY AND PRINCIPAL FINDINGS: Intact recombinant PrP exerted antibacterial and antifungal effects at normal and low pH. Studies employing r...

  16. New insights into structural determinants of prion protein folding and stability.

    Science.gov (United States)

    Benetti, Federico; Legname, Giuseppe

    2015-01-01

    Prions are the etiological agent of fatal neurodegenerative diseases called prion diseases or transmissible spongiform encephalopathies. These maladies can be sporadic, genetic or infectious disorders. Prions are due to post-translational modifications of the cellular prion protein leading to the formation of a β-sheet enriched conformer with altered biochemical properties. The molecular events causing prion formation in sporadic prion diseases are still elusive. Recently, we published a research elucidating the contribution of major structural determinants and environmental factors in prion protein folding and stability. Our study highlighted the crucial role of octarepeats in stabilizing prion protein; the presence of a highly enthalpically stable intermediate state in prion-susceptible species; and the role of disulfide bridge in preserving native fold thus avoiding the misfolding to a β-sheet enriched isoform. Taking advantage from these findings, in this work we present new insights into structural determinants of prion protein folding and stability.

  17. Controlling the prion propensity of glutamine/asparagine-rich proteins.

    Science.gov (United States)

    Paul, Kacy R; Ross, Eric D

    2015-01-01

    The yeast Saccharomyces cerevisiae can harbor a number of distinct prions. Most of the yeast prion proteins contain a glutamine/asparagine (Q/N) rich region that drives prion formation. Prion-like domains, defined as regions with high compositional similarity to yeast prion domains, are common in eukaryotic proteomes, and mutations in various human proteins containing prion-like domains have been linked to degenerative diseases, including amyotrophic lateral sclerosis. Here, we discuss a recent study in which we utilized two strategies to generate prion activity in non-prion Q/N-rich domains. First, we made targeted mutations in four non-prion Q/N-rich domains, replacing predicted prion-inhibiting amino acids with prion-promoting amino acids. All four mutants formed foci when expressed in yeast, and two acquired bona fide prion activity. Prion activity could be generated with as few as two mutations, suggesting that many non-prion Q/N-rich proteins may be just a small number of mutations from acquiring aggregation or prion activity. Second, we created tandem repeats of short prion-prone segments, and observed length-dependent prion activity. These studies demonstrate the considerable progress that has been made in understanding the sequence basis for aggregation of prion and prion-like domains, and suggest possible mechanisms by which new prion domains could evolve.

  18. Prion protein in milk.

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    Nicola Franscini

    Full Text Available BACKGROUND: Prions are known to cause transmissible spongiform encephalopathies (TSE after accumulation in the central nervous system. There is increasing evidence that prions are also present in body fluids and that prion infection by blood transmission is possible. The low concentration of the proteinaceous agent in body fluids and its long incubation time complicate epidemiologic analysis and estimation of spreading and thus the risk of human infection. This situation is particularly unsatisfactory for food and pharmaceutical industries, given the lack of sensitive tools for monitoring the infectious agent. METHODOLOGY/PRINCIPAL FINDINGS: We have developed an adsorption matrix, Alicon PrioTrap, which binds with high affinity and specificity to prion proteins. Thus we were able to identify prion protein (PrP(C--the precursor of prions (PrP(Sc--in milk from humans, cows, sheep, and goats. The absolute amount of PrP(C differs between the species (from microg/l range in sheep to ng/l range in human milk. PrP(C is also found in homogenised and pasteurised off-the-shelf milk, and even ultrahigh temperature treatment only partially diminishes endogenous PrP(C concentration. CONCLUSIONS/SIGNIFICANCE: In view of a recent study showing evidence of prion replication occurring in the mammary gland of scrapie infected sheep suffering from mastitis, the appearance of PrP(C in milk implies the possibility that milk of TSE-infected animals serves as source for PrP(Sc.

  19. How does domain replacement affect fibril formation of the rabbit/human prion proteins.

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    Xu Yan

    Full Text Available It is known that in vivo human prion protein (PrP have the tendency to form fibril deposits and are associated with infectious fatal prion diseases, while the rabbit PrP does not readily form fibrils and is unlikely to cause prion diseases. Although we have previously demonstrated that amyloid fibrils formed by the rabbit PrP and the human PrP have different secondary structures and macromolecular crowding has different effects on fibril formation of the rabbit/human PrPs, we do not know which domains of PrPs cause such differences. In this study, we have constructed two PrP chimeras, rabbit chimera and human chimera, and investigated how domain replacement affects fibril formation of the rabbit/human PrPs.As revealed by thioflavin T binding assays and Sarkosyl-soluble SDS-PAGE, the presence of a strong crowding agent dramatically promotes fibril formation of both chimeras. As evidenced by circular dichroism, Fourier transform infrared spectroscopy, and proteinase K digestion assays, amyloid fibrils formed by human chimera have secondary structures and proteinase K-resistant features similar to those formed by the human PrP. However, amyloid fibrils formed by rabbit chimera have proteinase K-resistant features and secondary structures in crowded physiological environments different from those formed by the rabbit PrP, and secondary structures in dilute solutions similar to the rabbit PrP. The results from transmission electron microscopy show that macromolecular crowding caused human chimera but not rabbit chimera to form short fibrils and non-fibrillar particles.We demonstrate for the first time that the domains beyond PrP-H2H3 (β-strand 1, α-helix 1, and β-strand 2 have a remarkable effect on fibrillization of the rabbit PrP but almost no effect on the human PrP. Our findings can help to explain why amyloid fibrils formed by the rabbit PrP and the human PrP have different secondary structures and why macromolecular crowding has different

  20. Prion Strain Characterization of a Novel Subtype of Creutzfeldt-Jakob Disease.

    Science.gov (United States)

    Galeno, Roberta; Di Bari, Michele Angelo; Nonno, Romolo; Cardone, Franco; Sbriccoli, Marco; Graziano, Silvia; Ingrosso, Loredana; Fiorini, Michele; Valanzano, Angelina; Pasini, Giulia; Poleggi, Anna; Vinci, Ramona; Ladogana, Anna; Puopolo, Maria; Monaco, Salvatore; Agrimi, Umberto; Zanusso, Gianluigi; Pocchiari, Maurizio

    2017-06-01

    In 2007, we reported a patient with an atypical form of Creutzfeldt-Jakob disease (CJD) heterozygous for methionine-valine (MV) at codon 129 who showed a novel pathological prion protein (PrP TSE ) conformation with an atypical glycoform (AG) profile and intraneuronal PrP deposition. In the present study, we further characterize the conformational properties of this pathological prion protein (PrP TSE MV AG ), showing that PrP TSE MV AG is composed of multiple conformers with biochemical properties distinct from those of PrP TSE type 1 and type 2 of MV sporadic CJD (sCJD). Experimental transmission of CJD-MV AG to bank voles and gene-targeted transgenic mice carrying the human prion protein gene (TgHu mice) showed unique transmission rates, survival times, neuropathological changes, PrP TSE deposition patterns, and PrP TSE glycotypes that are distinct from those of sCJD-MV1 and sCJD-MV2. These biochemical and experimental data suggest the presence of a novel prion strain in CJD-MV AG IMPORTANCE Sporadic Creutzfeldt-Jakob disease is caused by the misfolding of the cellular prion protein, which assumes two different major conformations (type 1 and type 2) and, together with the methionine/valine polymorphic codon 129 of the prion protein gene, contribute to the occurrence of distinct clinical-pathological phenotypes. Inoculation in laboratory rodents of brain tissues from the six possible combinations of pathological prion protein types with codon 129 genotypes results in the identification of 3 or 4 strains of prions. We report on the identification of a novel strain of Creutzfeldt-Jakob disease isolated from a patient who carried an abnormally glycosylated pathological prion protein. This novel strain has unique biochemical characteristics, does not transmit to humanized transgenic mice, and shows exclusive transmission properties in bank voles. The identification of a novel human prion strain improves our understanding of the pathogenesis of the disease and of

  1. Classical Bovine Spongiform Encephalopathy by Transmission of H-Type Prion in Homologous Prion Protein Context

    Science.gov (United States)

    Andréoletti, Olivier; Lacroux, Caroline; Prieto, Irene; Lorenzo, Patricia; Larska, Magdalena; Baron, Thierry; Espinosa, Juan-Carlos

    2011-01-01

    Bovine spongiform encephalopathy (BSE) and BSE-related disorders have been associated with a single major prion strain. Recently, 2 atypical, presumably sporadic forms of BSE have been associated with 2 distinct prion strains that are characterized mainly by distinct Western blot profiles of abnormal protease-resistant prion protein (PrPres), named high-type (BSE-H) and low-type (BSE-L), that also differed from classical BSE. We characterized 5 atypical BSE-H isolates by analyzing their molecular and neuropathologic properties during transmission in transgenic mice expressing homologous bovine prion protein. Unexpectedly, in several inoculated animals, strain features emerged that were highly similar to those of classical BSE agent. These findings demonstrate the capability of an atypical bovine prion to acquire classical BSE–like properties during propagation in a homologous bovine prion protein context and support the view that the epidemic BSE agent could have originated from such a cattle prion. PMID:21888788

  2. A review of drug therapy for sporadic fatal insomnia.

    Science.gov (United States)

    Tabaee Damavandi, Pardis; Dove, Martin T; Pickersgill, Richard W

    2017-09-03

    Sporadic fatal insomnia (sFI) is a rapid progressive neurodegenerative disease characterised by gradual to perpetual insomnia, followed by dysautonomia, coma and death. 1 The cause of sFI was recently mapped to a mutation in a protein, the prion, found in the human brain. It is the unfolding of the prion that leads to the generation of toxic oligomers that destroy brain tissue and function. Recent studies have confirmed that a methionine mutation at codon 129 of the human Prion is characteristic of sFI. Current treatment slows down the progression of the disease, but no cure has been found, yet. We used Molecular Docking and Molecular Dynamics simulation methods, to study the toxic Fatal-Insomnia-prion conformations at local unfolding. The idea was to determine these sites and to stabilise these regions against unfolding and miss-folding, using a small ligand, based on a phenothiazine "moiety". As a result we here discuss current fatal insomnia therapy and present seven novel possible compounds for in vitro and in vivo screening.

  3. Genetic prion disease: no role for the immune system in disease pathogenesis?

    Science.gov (United States)

    Friedman-Levi, Yael; Binyamin, Orli; Frid, Kati; Ovadia, Haim; Gabizon, Ruth

    2014-08-01

    Prion diseases, which can manifest by transmissible, sporadic or genetic etiologies, share several common features, such as a fatal neurodegenerative outcome and the aberrant accumulation of proteinase K (PK)-resistant PrP forms in the CNS. In infectious prion diseases, such as scrapie in mice, prions first replicate in immune organs, then invade the CNS via ascending peripheral tracts, finally causing death. Accelerated neuroinvasion and death occurs when activated prion-infected immune cells infiltrate into the CNS, as is the case for scrapie-infected mice induced for experimental autoimmune encephalomyelitis (EAE), a CNS inflammatory insult. To establish whether the immune system plays such a central role also in genetic prion diseases, we induced EAE in TgMHu2ME199K mice, a line mimicking for late onset genetic Creutzfeldt Jacob disease (gCJD), a human prion disease. We show here that EAE induction of TgMHu2ME199K mice neither accelerated nor aggravated prion disease manifestation. Concomitantly, we present evidence that PK-resistant PrP forms were absent from CNS immune infiltrates, and most surprisingly also from lymph nodes and spleens of TgMHu2ME199K mice at all ages and stages of disease. These results imply that the mechanism of genetic prion disease differs widely from that of the infectious presentation, and that the conversion of mutant PrPs into PK resistant forms occurs mostly/only in the CNS. If the absence of pathogenic PrP forms form immune organs is also true for gCJD patients, it may suggest their blood is devoid of prion infectivity. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Prions, prion-like prionoids, and neurodegenerative disordersVacancy

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    Ashok Verma

    2016-01-01

    Full Text Available Prion diseases or transmissible spongiform encephalopathies are fatal neurodegenerative diseases characterized by the aggregation and deposition of the misfolded prion protein in the brain. α-synuclein (α-syn-associated multiple system atrophy has been recently shown to be caused by a bona fide α-syn prion strain. Several other misfolded native proteins such as β-amyloid, tau and TDP-43 share some aspects of prions although none of them is shown to be transmissible in nature or in experimental animals. However, these prion-like “prionoids” are causal to a variety of neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. The remarkable recent discovery of at least two new α-syn prion strains and their transmissibility in transgenic mice and in vitro cell models raises a distinct question as to whether some specific strain of other prionoids could have the capability of disease transmission in a manner similar to prions. In this overview, we briefly describe human and other mammalian prion diseases and comment on certain similarities between prion and prionoid and the possibility of prion-like transmissibility of some prionoid strains.

  5. Soluble Aβ aggregates can inhibit prion propagation.

    Science.gov (United States)

    Sarell, Claire J; Quarterman, Emma; Yip, Daniel C-M; Terry, Cassandra; Nicoll, Andrew J; Wadsworth, Jonathan D F; Farrow, Mark A; Walsh, Dominic M; Collinge, John

    2017-11-01

    Mammalian prions cause lethal neurodegenerative diseases such as Creutzfeldt-Jakob disease (CJD) and consist of multi-chain assemblies of misfolded cellular prion protein (PrP C ). Ligands that bind to PrP C can inhibit prion propagation and neurotoxicity. Extensive prior work established that certain soluble assemblies of the Alzheimer's disease (AD)-associated amyloid β-protein (Aβ) can tightly bind to PrP C , and that this interaction may be relevant to their toxicity in AD. Here, we investigated whether such soluble Aβ assemblies might, conversely, have an inhibitory effect on prion propagation. Using cellular models of prion infection and propagation and distinct Aβ preparations, we found that the form of Aβ assemblies which most avidly bound to PrP in vitro also inhibited prion infection and propagation. By contrast, forms of Aβ which exhibit little or no binding to PrP were unable to attenuate prion propagation. These data suggest that soluble aggregates of Aβ can compete with prions for binding to PrP C and emphasize the bidirectional nature of the interplay between Aβ and PrP C in Alzheimer's and prion diseases. Such inhibitory effects of Aβ on prion propagation may contribute to the apparent fall-off in the incidence of sporadic CJD at advanced age where cerebral Aβ deposition is common. © 2017 The Authors.

  6. Encephalopathy for prions

    International Nuclear Information System (INIS)

    Colegial, Carlos; Silva, Federico; Perez, Carlos

    1999-01-01

    The encephalopathy spongyform for prions are neuro degenerative illness that can be sporadic or transferable, for infectious or hereditary mechanisms. Their investigation has outlined enormous challenges and in the historical journey in search of its cause two doctors have received the Nobel prize of medicine Carleton Gajdusek, for its works in New Guinea where it described the infectious transmission for cannibalistic rites that it took to studies of experimental transmission in chimpanzees and to its theory of the slow virus; later on, Stanley Prusiner developed its experimental works in hamsters, throwing to the neurobiology the prion concept (particles infectious proteinaceous not viral). The paper narrates the history of a patient that died in the San Juan de Dios of Bogota Hospital by cause of this prionic illness and clinical and pathological aspects are discussed

  7. Spermidine cures yeast of prions

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    Shaun H. Speldewinde

    2015-12-01

    Full Text Available Prions are self-perpetuating amyloid protein aggregates which underlie various neurodegenerative diseases in mammals. The molecular basis underlying their conversion from a normally soluble protein into the prion form remains largely unknown. Studies aimed at uncovering these mechanism(s are therefore essential if we are to develop effective therapeutic strategies to counteract these disease-causing entities. Autophagy is a cellular degradation system which has predominantly been considered as a non-selective bulk degradation process which recycles macromolecules in response to starvation conditions. We now know that autophagy also serves as a protein quality control mechanism which selectively degrades protein aggregates and damaged organelles. These are commonly accumulated in various neurodegenerative disorders including prion diseases. In our recent study [Speldewinde et al. Mol. Biol. Cell. (2015] we used the well-established yeast [PSI+]/Sup35 and [PIN­+]/Rnq1 prion models to show that autophagy prevents sporadic prion formation. Importantly, we found that spermidine, a polyamine that has been used to increase autophagic flux, acts as a protective agent which prevents spontaneous prion formation.

  8. Sporadic naturally occurring melanoma in dogs as a preclinical model for human melanoma.

    Science.gov (United States)

    Simpson, R Mark; Bastian, Boris C; Michael, Helen T; Webster, Joshua D; Prasad, Manju L; Conway, Catherine M; Prieto, Victor M; Gary, Joy M; Goldschmidt, Michael H; Esplin, D Glen; Smedley, Rebecca C; Piris, Adriano; Meuten, Donald J; Kiupel, Matti; Lee, Chyi-Chia R; Ward, Jerrold M; Dwyer, Jennifer E; Davis, Barbara J; Anver, Miriam R; Molinolo, Alfredo A; Hoover, Shelley B; Rodriguez-Canales, Jaime; Hewitt, Stephen M

    2014-01-01

    Melanoma represents a significant malignancy in humans and dogs. Different from genetically engineered models, sporadic canine melanocytic neoplasms share several characteristics with human disease that could make dogs a more relevant preclinical model. Canine melanomas rarely arise in sun-exposed sites. Most occur in the oral cavity, with a subset having intra-epithelial malignant melanocytes mimicking the in situ component of human mucosal melanoma. The spectrum of canine melanocytic neoplasia includes benign lesions with some analogy to nevi, as well as invasive primary melanoma, and widespread metastasis. Growing evidence of distinct subtypes in humans, differing in somatic and predisposing germ-line genetic alterations, cell of origin, epidemiology, relationship to ultraviolet radiation and progression from benign to malignant tumors, may also exist in dogs. Canine and human mucosal melanomas appear to harbor BRAF, NRAS, and c-kit mutations uncommonly, compared with human cutaneous melanomas, although both species share AKT and MAPK signaling activation. We conclude that there is significant overlap in the clinical and histopathological features of canine and human mucosal melanomas. This represents opportunity to explore canine oral cavity melanoma as a preclinical model. © 2013 The Authors. Pigment Cell & Melanoma Research published by John Wiley & Sons Ltd.

  9. Activation of human natural killer cells by the soluble form of cellular prion protein

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Yeon-Jae [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Hafis Clinic, Seoul (Korea, Republic of); Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Bum-Chan [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Park, Su-Hyung [Laboratory of Translational Immunology and Vaccinology, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Young Woo [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Shin, Eui-Cheol, E-mail: ecshin@kaist.ac.kr [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of)

    2015-08-21

    Cellular prion protein (PrP{sup C}) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP{sup C} in the immune system have not been clearly elucidated. In the present study, we investigated the effects of a soluble form of recombinant PrP{sup C} protein on human natural killer (NK) cells. Recombinant soluble PrP{sup C} protein was generated by fusion of human PrP{sup C} with the Fc portion of human IgG{sub 1} (PrP{sup C}-Fc). PrP{sup C}-Fc binds to the surface of human NK cells, particularly to CD56{sup dim} NK cells. PrP{sup C}-Fc induced the production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP{sup C}-Fc facilitated the IL-15-induced proliferation of NK cells. PrP{sup C}-Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP{sup C}-Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP{sup C} (PrP{sup C}-Fc) was generated by fusion of human PrP{sup C} with IgG1 Fc portion. • PrP{sup C}-Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP{sup C}-Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways.

  10. Activation of human natural killer cells by the soluble form of cellular prion protein

    International Nuclear Information System (INIS)

    Seong, Yeon-Jae; Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon; Park, Bum-Chan; Park, Su-Hyung; Park, Young Woo; Shin, Eui-Cheol

    2015-01-01

    Cellular prion protein (PrP C ) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP C in the immune system have not been clearly elucidated. In the present study, we investigated the effects of a soluble form of recombinant PrP C protein on human natural killer (NK) cells. Recombinant soluble PrP C protein was generated by fusion of human PrP C with the Fc portion of human IgG 1 (PrP C -Fc). PrP C -Fc binds to the surface of human NK cells, particularly to CD56 dim NK cells. PrP C -Fc induced the production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP C -Fc facilitated the IL-15-induced proliferation of NK cells. PrP C -Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP C -Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP C -Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP C (PrP C -Fc) was generated by fusion of human PrP C with IgG1 Fc portion. • PrP C -Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP C -Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP C -Fc protein activates human NK cells via the ERK and JNK signaling pathways

  11. Evidence for presumable feline origin of sporadic G6P[9] rotaviruses in humans.

    Science.gov (United States)

    Pietsch, Corinna; Liebert, Uwe G

    2018-05-31

    Species A rotaviruses are highly diverse and impose a substantial burden to human and animal health. Interspecies transmission between livestock, domestic animals and humans is commonly observed, but spread of animal-like rotaviruses within the human population is limited. During the continued monitoring of rotavirus strains in Germany, an unusual G6P[9] rotavirus strain was detected in feces of a child. The complete rotavirus coding sequences revealed a unique G6-P[9]-I2-R2-C2-M2-A3-N2-T3-E2-H3 genotype constellation. The virus was phylogenetically related to feline G3P[9] strains and other human G6P[9] rotaviruses of presumable zoonotic origin. Analysis of primer binding sites of G6 specific genotyping revealed further evidence of a G6P[9] feline reservoir. Moreover, substantial deficits of conventional semi-nested PCR genotyping approaches in detecting contemporary G6P[9] were revealed. Rotavirus strain GER29-14 most likely resulted from a direct or recent interspecies transmission from a cat to human. Further studies could assess nucleic acid sequences and genotype constellations of feline rotavirus to confirm the likely feline origin of sporadic human G6P[9] strains. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Protease-sensitive synthetic prions.

    Directory of Open Access Journals (Sweden)

    David W Colby

    2010-01-01

    Full Text Available Prions arise when the cellular prion protein (PrP(C undergoes a self-propagating conformational change; the resulting infectious conformer is designated PrP(Sc. Frequently, PrP(Sc is protease-resistant but protease-sensitive (s prions have been isolated in humans and other animals. We report here that protease-sensitive, synthetic prions were generated in vitro during polymerization of recombinant (rec PrP into amyloid fibers. In 22 independent experiments, recPrP amyloid preparations, but not recPrP monomers or oligomers, transmitted disease to transgenic mice (n = 164, denoted Tg9949 mice, that overexpress N-terminally truncated PrP. Tg9949 control mice (n = 174 did not spontaneously generate prions although they were prone to late-onset spontaneous neurological dysfunction. When synthetic prion isolates from infected Tg9949 mice were serially transmitted in the same line of mice, they exhibited sPrP(Sc and caused neurodegeneration. Interestingly, these protease-sensitive prions did not shorten the life span of Tg9949 mice despite causing extensive neurodegeneration. We inoculated three synthetic prion isolates into Tg4053 mice that overexpress full-length PrP; Tg4053 mice are not prone to developing spontaneous neurological dysfunction. The synthetic prion isolates caused disease in 600-750 days in Tg4053 mice, which exhibited sPrP(Sc. These novel synthetic prions demonstrate that conformational changes in wild-type PrP can produce mouse prions composed exclusively of sPrP(Sc.

  13. Defining the conformational features of anchorless, poorly neuroinvasive prions.

    Directory of Open Access Journals (Sweden)

    Cyrus Bett

    Full Text Available Infectious prions cause diverse clinical signs and form an extraordinary range of structures, from amorphous aggregates to fibrils. How the conformation of a prion dictates the disease phenotype remains unclear. Mice expressing GPI-anchorless or GPI-anchored prion protein exposed to the same infectious prion develop fibrillar or nonfibrillar aggregates, respectively, and show a striking divergence in the disease pathogenesis. To better understand how a prion's physical properties govern the pathogenesis, infectious anchorless prions were passaged in mice expressing anchorless prion protein and the resulting prions were biochemically characterized. Serial passage of anchorless prions led to a significant decrease in the incubation period to terminal disease and altered the biochemical properties, consistent with a transmission barrier effect. After an intraperitoneal exposure, anchorless prions were only weakly neuroinvasive, as prion plaques rarely occurred in the brain yet were abundant in extracerebral sites such as heart and adipose tissue. Anchorless prions consistently showed very high stability in chaotropes or when heated in SDS, and were highly resistant to enzyme digestion. Consistent with the results in mice, anchorless prions from a human patient were also highly stable in chaotropes. These findings reveal that anchorless prions consist of fibrillar and highly stable conformers. The additional finding from our group and others that both anchorless and anchored prion fibrils are poorly neuroinvasive strengthens the hypothesis that a fibrillar prion structure impedes efficient CNS invasion.

  14. Prokineticin 1 protein expression is a useful new prognostic factor for human sporadic colorectal cancer.

    Science.gov (United States)

    Nakazawa, Toshiyuki; Goi, Takanori; Hirono, Yasuo; Yamaguchi, Akio

    2015-05-01

    Hematogenous metastasis, regarded as closely related to angiogenic growth factors, is associated with colorectal cancer prognosis. The angiogenic growth factor prokineticin 1 (PROK1) has been cloned from endocrine cells. However, its protein expression in human malignant tumors has not been studied. The current study established the anti-PROK1 monoclonal antibody (mAb) and examined the relationship between the expression of PROK1 protein and human colorectal cancer. The expression of PROK1 protein was assessed in 620 resected sporadic colorectal cancer tissue samples by immunohistochemical staining with in-house-developed human PROK1 mAb to investigate the relationship of PROK1 expression to clinicopathologic factors, recurrence, and survival rate and to evaluate its prognostic significance. The expression of PROK1 protein was detected in 36 % (223/620) of human primary colorectal cancer lesions but no in the healthy mucosa adjacent to the colorectal cancer lesions. According to the clinicopathologic examinations, the frequency of positive PROK1 expression was significantly higher in cases with serosal invasion, lymphatic invasion, venous invasion, lymph node metastasis, liver metastasis, hematogenous metastasis, and higher stage disease. The recurrence rate and prognosis for patients with PROK1 expression-positive lesions were significantly worse. In the Cox proportional hazard model, PROK1 expression was an independent prognostic factor. The expression of PROK1 protein was identified for the first time as a new prognostic factor in colorectal cancer.

  15. Mammalian prions

    Science.gov (United States)

    Salamat, Muhammad Khalid; Munoz-Montesino, Carola; Moudjou, Mohammed; Rezaei, Human; Laude, Hubert; Béringue, Vincent; Dron, Michel

    2013-01-01

    Upon prion infection, abnormal prion protein (PrPSc) self-perpetuate by conformational conversion of α-helix-rich PrPC into β sheet enriched form, leading to formation and deposition of PrPSc aggregates in affected brains. However the process remains poorly understood at the molecular level and the regions of PrP critical for conversion are still debated. Minimal amino acid substitutions can impair prion replication at many places in PrP. Conversely, we recently showed that bona fide prions could be generated after introduction of eight and up to 16 additional amino acids in the H2-H3 inter-helix loop of PrP. Prion replication also accommodated the insertions of an octapeptide at different places in the last turns of H2. This reverse genetic approach reveals an unexpected tolerance of prions to substantial sequence changes in the protease-resistant part which is associated with infectivity. It also demonstrates that conversion does not require the presence of a specific sequence in the middle of the H2-H3 area. We discuss the implications of our findings according to different structural models proposed for PrPSc and questioned the postulated existence of an N- or C-terminal prion domain in the protease-resistant region. PMID:23232499

  16. Classifying prion and prion-like phenomena.

    Science.gov (United States)

    Harbi, Djamel; Harrison, Paul M

    2014-01-01

    The universe of prion and prion-like phenomena has expanded significantly in the past several years. Here, we overview the challenges in classifying this data informatically, given that terms such as "prion-like", "prion-related" or "prion-forming" do not have a stable meaning in the scientific literature. We examine the spectrum of proteins that have been described in the literature as forming prions, and discuss how "prion" can have a range of meaning, with a strict definition being for demonstration of infection with in vitro-derived recombinant prions. We suggest that although prion/prion-like phenomena can largely be apportioned into a small number of broad groups dependent on the type of transmissibility evidence for them, as new phenomena are discovered in the coming years, a detailed ontological approach might be necessary that allows for subtle definition of different "flavors" of prion / prion-like phenomena.

  17. Source attribution of human salmonellosis using a meta-analysis of case-control studies of sporadic infections

    DEFF Research Database (Denmark)

    Coutinho Calado Domingues, Ana Rita; Pires, Sara Monteiro; Hisham Beshara Halasa, Tariq

    2012-01-01

    Salmonella is an important cause of human illness. Disease is frequently associated with foodborne transmission, but other routes of exposure are recognized. Identifying sources of disease is essential for prioritizing public health interventions. Numerous case-control studies of sporadic salmone...

  18. Parasitic, fungal and prion zoonoses: an expanding universe of candidates for human disease.

    Science.gov (United States)

    Akritidis, N

    2011-03-01

    Zoonotic infections have emerged as a burden for millions of people in recent years, owing to re-emerging or novel pathogens often causing outbreaks in the developing world in the presence of inadequate public health infrastructure. Among zoonotic infections, those caused by parasitic pathogens are the ones that affect millions of humans worldwide, who are also at risk of developing chronic disease. The present review discusses the global effect of protozoan pathogens such as Leishmania sp., Trypanosoma sp., and Toxoplasma sp., as well as helminthic pathogens such as Echinococcus sp., Fasciola sp., and Trichinella sp. The zoonotic aspects of agents that are not essentially zoonotic are also discussed. The review further focuses on the zoonotic dynamics of fungal pathogens and prion diseases as observed in recent years, in an evolving environment in which novel patient target groups have developed for agents that were previously considered to be obscure or of minimal significance. © 2011 The Author. Clinical Microbiology and Infection © 2011 European Society of Clinical Microbiology and Infectious Diseases.

  19. A role for astroglia in prion diseases.

    Science.gov (United States)

    Aguzzi, Adriano; Liu, Yingjun

    2017-12-04

    In this issue of JEM, Krejciova et al. (https://doi.org/10.1084/jem.20161547) report that astrocytes derived from human iPSCs can replicate human CJD prions. These observations provide a new, potentially very valuable model for studying human prions in cellula and for identifying antiprion compounds that might serve as clinical candidates. Furthermore, they add to the evidence that astrocytes may not be just innocent bystanders in prion diseases. © 2017 Aguzzi and Liu.

  20. Binding affinity toward human prion protein of some anti-prion compounds - Assessment based on QSAR modeling, molecular docking and non-parametric ranking.

    Science.gov (United States)

    Kovačević, Strahinja; Karadžić, Milica; Podunavac-Kuzmanović, Sanja; Jevrić, Lidija

    2018-01-01

    The present study is based on the quantitative structure-activity relationship (QSAR) analysis of binding affinity toward human prion protein (huPrP C ) of quinacrine, pyridine dicarbonitrile, diphenylthiazole and diphenyloxazole analogs applying different linear and non-linear chemometric regression techniques, including univariate linear regression, multiple linear regression, partial least squares regression and artificial neural networks. The QSAR analysis distinguished molecular lipophilicity as an important factor that contributes to the binding affinity. Principal component analysis was used in order to reveal similarities or dissimilarities among the studied compounds. The analysis of in silico absorption, distribution, metabolism, excretion and toxicity (ADMET) parameters was conducted. The ranking of the studied analogs on the basis of their ADMET parameters was done applying the sum of ranking differences, as a relatively new chemometric method. The main aim of the study was to reveal the most important molecular features whose changes lead to the changes in the binding affinities of the studied compounds. Another point of view on the binding affinity of the most promising analogs was established by application of molecular docking analysis. The results of the molecular docking were proven to be in agreement with the experimental outcome. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Antimicrobial activity of human prion protein is mediated by its N-terminal region.

    Directory of Open Access Journals (Sweden)

    Mukesh Pasupuleti

    Full Text Available BACKGROUND: Cellular prion-related protein (PrP(c is a cell-surface protein that is ubiquitously expressed in the human body. The multifunctionality of PrP(c, and presence of an exposed cationic and heparin-binding N-terminus, a feature characterizing many antimicrobial peptides, made us hypothesize that PrP(c could exert antimicrobial activity. METHODOLOGY AND PRINCIPAL FINDINGS: Intact recombinant PrP exerted antibacterial and antifungal effects at normal and low pH. Studies employing recombinant PrP and N- and C-terminally truncated variants, as well as overlapping peptide 20mers, demonstrated that the antimicrobial activity is mediated by the unstructured N-terminal part of the protein. Synthetic peptides of the N-terminus of PrP killed the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, and the Gram-positive Bacillus subtilis and Staphylococcus aureus, as well as the fungus Candida parapsilosis. Fluorescence studies of peptide-treated bacteria, paired with analysis of peptide effects on liposomes, showed that the peptides exerted membrane-breaking effects similar to those seen after treatment with the "classical" human antimicrobial peptide LL-37. In contrast to LL-37, however, no marked helix induction was detected for the PrP-derived peptides in presence of negatively charged (bacteria-mimicking liposomes. PrP furthermore showed an inducible expression during wounding of human skin ex vivo and in vivo, as well as stimulation of keratinocytes with TGF-alpha in vitro. CONCLUSIONS: The demonstration of an antimicrobial activity of PrP, localisation of its activity to the N-terminal and heparin-binding region, combined with results showing an increased expression of PrP during wounding, indicate that PrPs could have a previously undisclosed role in host defense.

  2. Classical Bovine Spongiform Encephalopathy by Transmission of H-Type Prion in Homologous Prion Protein Context

    OpenAIRE

    Torres, Juan-María; Andréoletti, Olivier; Lacroux, Caroline; Prieto, Irene; Lorenzo, Patricia; Larska, Magdalena; Baron, Thierry; Espinosa, Juan-Carlos

    2011-01-01

    Bovine spongiform encephalopathy (BSE) and BSErelated disorders have been associated with a single major prion strain. Recently, 2 atypical, presumably sporadic forms of BSE have been associated with 2 distinct prion strains that are characterized mainly by distinct Western blot profi les of abnormal protease-resistant prion protein (PrPres), named high-type (BSE-H) and low-type (BSE-L), that also differed from classical BSE. We characterized 5 atypical BSE-H isolates by analyzing their molec...

  3. Peripheral Tissue Involvement in Sporadic, Iatrogenic, and Variant Creutzfeldt-Jakob Disease

    Science.gov (United States)

    Head, Mark W.; Ritchie, Diane; Smith, Nadine; McLoughlin, Victoria; Nailon, William; Samad, Sazia; Masson, Stephen; Bishop, Matthew; McCardle, Linda; Ironside, James W.

    2004-01-01

    Human prion diseases are rare fatal neurodegenerative conditions that occur as acquired, familial, or idiopathic disorders. A key event in their pathogenesis is the accumulation of an altered form of the prion protein, termed PrPSc, in the central nervous system. A novel acquired human prion disease, variant Creutzfeldt-Jakob disease, is thought to result from oral exposure to the bovine spongiform encephalopathy agent. This disease differs from other human prion diseases in its neurological, neuropathological, and biochemical phenotype. We have used immunohistochemistry and Western blot techniques to analyze the tissue distribution and biochemical properties of PrPSc in peripheral tissues in a unique series of nine cases of variant Creutzfeldt-Jakob disease. We have compared this with the distribution and biochemical forms found in all of the major subtypes of sporadic Creutzfeldt-Jakob disease and in a case of iatrogenic Creutzfeldt-Jakob disease associated with growth hormone therapy. The results show that involvement of the lymphoreticular system is a defining feature of variant Creutzfeldt-Jakob disease, but that the biochemical isoform of PrPSc found is influenced by the cell type in which it accumulates. PMID:14695328

  4. Prions in yeast

    OpenAIRE

    Bezdíčka, Martin

    2013-01-01

    The thesis describes yeast prions and their biological effects on yeast in general. It defines the basic characteristics of yeast prions, that distinguish prions from other proteins. The thesis introduces various possibilities of prion formation, and propagation as well as specific types of yeast prions, including various functions of most studied types of prions. The thesis also focuses on chaperones that affect the state of yeast prions in cells. Lastly, the thesis indicates similarities be...

  5. Yeast and Fungal Prions: Amyloid-Handling Systems, Amyloid Structure, and Prion Biology.

    Science.gov (United States)

    Wickner, R B; Edskes, H K; Gorkovskiy, A; Bezsonov, E E; Stroobant, E E

    2016-01-01

    Yeast prions (infectious proteins) were discovered by their outré genetic properties and have become important models for an array of human prion and amyloid diseases. A single prion protein can become any of many distinct amyloid forms (called prion variants or strains), each of which is self-propagating, but with different biological properties (eg, lethal vs mild). The folded in-register parallel β sheet architecture of the yeast prion amyloids naturally suggests a mechanism by which prion variant information can be faithfully transmitted for many generations. The yeast prions rely on cellular chaperones for their propagation, but can be cured by various chaperone imbalances. The Btn2/Cur1 system normally cures most variants of the [URE3] prion that arise. Although most variants of the [PSI+] and [URE3] prions are toxic or lethal, some are mild in their effects. Even the most mild forms of these prions are rare in the wild, indicating that they too are detrimental to yeast. The beneficial [Het-s] prion of Podospora anserina poses an important contrast in its structure, biology, and evolution to the yeast prions characterized thus far. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Prion Infectivity in Fat of Deer with Chronic Wasting Disease▿

    OpenAIRE

    Race, Brent; Meade-White, Kimberly; Race, Richard; Chesebro, Bruce

    2009-01-01

    Chronic wasting disease (CWD) is a neurodegenerative prion disease of cervids. Some animal prion diseases, such as bovine spongiform encephalopathy, can infect humans; however, human susceptibility to CWD is unknown. In ruminants, prion infectivity is found in central nervous system and lymphoid tissues, with smaller amounts in intestine and muscle. In mice, prion infectivity was recently detected in fat. Since ruminant fat is consumed by humans and fed to animals, we determined infectivity t...

  7. Altered Ca2+ homeostasis induces Calpain-Cathepsin axis activation in sporadic Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Llorens, Franc; Thüne, Katrin; Sikorska, Beata; Schmitz, Matthias; Tahir, Waqas; Fernández-Borges, Natalia; Cramm, Maria; Gotzmann, Nadine; Carmona, Margarita; Streichenberger, Nathalie; Michel, Uwe; Zafar, Saima; Schuetz, Anna-Lena; Rajput, Ashish; Andréoletti, Olivier; Bonn, Stefan; Fischer, Andre; Liberski, Pawel P; Torres, Juan Maria; Ferrer, Isidre; Zerr, Inga

    2017-04-27

    Sporadic Creutzfeldt-Jakob disease (sCJD) is the most prevalent form of human prion disease and it is characterized by the presence of neuronal loss, spongiform degeneration, chronic inflammation and the accumulation of misfolded and pathogenic prion protein (PrP Sc ). The molecular mechanisms underlying these alterations are largely unknown, but the presence of intracellular neuronal calcium (Ca 2+ ) overload, a general feature in models of prion diseases, is suggested to play a key role in prion pathogenesis.Here we describe the presence of massive regulation of Ca 2+ responsive genes in sCJD brain tissue, accompanied by two Ca 2+ -dependent processes: endoplasmic reticulum stress and the activation of the cysteine proteases Calpains 1/2. Pathogenic Calpain proteins activation in sCJD is linked to the cleavage of their cellular substrates, impaired autophagy and lysosomal damage, which is partially reversed by Calpain inhibition in a cellular prion model. Additionally, Calpain 1 treatment enhances seeding activity of PrP Sc in a prion conversion assay. Neuronal lysosomal impairment caused by Calpain over activation leads to the release of the lysosomal protease Cathepsin S that in sCJD mainly localises in axons, although massive Cathepsin S overexpression is detected in microglial cells. Alterations in Ca 2+ homeostasis and activation of Calpain-Cathepsin axis already occur at pre-clinical stages of the disease as detected in a humanized sCJD mouse model.Altogether our work indicates that unbalanced Calpain-Cathepsin activation is a relevant contributor to the pathogenesis of sCJD at multiple molecular levels and a potential target for therapeutic intervention.

  8. Co-existence of Distinct Prion Types Enables Conformational Evolution of Human PrPSc by Competitive Selection

    NARCIS (Netherlands)

    Haldiman, T.; Kim, C.; Cohen, Y.; Chen, W.; Blevins, J.; Qing, L.; Cohen, M.L.; Langeveld, J.P.M.; Telling, G.C.; Kong, Q.; Safar, J.G.

    2013-01-01

    The unique phenotypic characteristics of mammalian prions are thought to be encoded in the conformation of pathogenic prion proteins (PrPSc). The molecular mechanism responsible for the adaptation, mutation, and evolution of prions observed in cloned cells and upon crossing the species barrier

  9. Adult human microglia secrete cytokines when exposed to neurotoxic prion protein peptide: no intermediary role for prostaglandin E2

    NARCIS (Netherlands)

    Veerhuis, Robert; Hoozemans, Jeroen J. M.; Janssen, Ingrid; Boshuizen, Ronald S.; Langeveld, Jan P. M.; Eikelenboom, Piet

    2002-01-01

    Prion diseases are characterized by accumulation of protease resistant isoforms of prion protein (termed PrP(SC)), glial activation and neurodegeneration. The time course of PrP deposition, appearance of activated microglia, and of neuronal apoptosis in experimentally-induced prion disease suggests

  10. Comparative syntheses of peptides and peptide thioesters derived from mouse and human prion proteins

    Czech Academy of Sciences Publication Activity Database

    Šebestík, Jaroslav; Zawada, Zbigniew; Šafařík, Martin; Hlaváček, Jan

    2012-01-01

    Roč. 43, č. 3 (2012), s. 1297-1309 ISSN 0939-4451 R&D Projects: GA ČR GA203/07/1517 Institutional research plan: CEZ:AV0Z40550506 Keywords : prion protein segments * classical synthesis * chemical ligation synthesis * peptide thioesters Subject RIV: CC - Organic Chemistry Impact factor: 3.914, year: 2012

  11. High diagnostic value of second generation CSF RT-QuIC across the wide spectrum of CJD prions.

    Science.gov (United States)

    Franceschini, Alessia; Baiardi, Simone; Hughson, Andrew G; McKenzie, Neil; Moda, Fabio; Rossi, Marcello; Capellari, Sabina; Green, Alison; Giaccone, Giorgio; Caughey, Byron; Parchi, Piero

    2017-09-06

    An early and accurate in vivo diagnosis of rapidly progressive dementia remains challenging, despite its critical importance for the outcome of treatable forms, and the formulation of prognosis. Real-Time Quaking-Induced Conversion (RT-QuIC) is an in vitro assay that, for the first time, specifically discriminates patients with prion disease. Here, using cerebrospinal fluid (CSF) samples from 239 patients with definite or probable prion disease and 100 patients with a definite alternative diagnosis, we compared the performance of the first (PQ-CSF) and second generation (IQ-CSF) RT-QuIC assays, and investigated the diagnostic value of IQ-CSF across the broad spectrum of human prions. Our results confirm the high sensitivity of IQ-CSF for detecting human prions with a sub-optimal sensitivity for the sporadic CJD subtypes MM2C and MM2T, and a low sensitivity limited to variant CJD, Gerstmann-Sträussler-Scheinker syndrome and fatal familial insomnia. While we found no difference in specificity between PQ-CSF and IQ-CSF, the latter showed a significant improvement in sensitivity, allowing prion detection in about 80% of PQ-CSF negative CJD samples. Our results strongly support the implementation of IQ-CSF in clinical practice. By rapidly confirming or excluding CJD with high accuracy the assay is expected to improve the outcome for patients and their enrollment in therapeutic trials.

  12. Application of quantitative DTI metrics in sporadic CJD

    Directory of Open Access Journals (Sweden)

    E. Caverzasi

    2014-01-01

    Full Text Available Diffusion Weighted Imaging is extremely important for the diagnosis of probable sporadic Jakob–Creutzfeldt disease, the most common human prion disease. Although visual assessment of DWI MRI is critical diagnostically, a more objective, quantifiable approach might more precisely identify the precise pattern of brain involvement. Furthermore, a quantitative, systematic tracking of MRI changes occurring over time might provide insights regarding the underlying histopathological mechanisms of human prion disease and provide information useful for clinical trials. The purposes of this study were: 1 to describe quantitatively the average cross-sectional pattern of reduced mean diffusivity, fractional anisotropy, atrophy and T1 relaxation in the gray matter (GM in sporadic Jakob–Creutzfeldt disease, 2 to study changes in mean diffusivity and atrophy over time and 3 to explore their relationship with clinical scales. Twenty-six sporadic Jakob–Creutzfeldt disease and nine control subjects had MRIs on the same scanner; seven sCJD subjects had a second scan after approximately two months. Cortical and subcortical gray matter regions were parcellated with Freesurfer. Average cortical thickness (or subcortical volume, T1-relaxiation and mean diffusivity from co-registered diffusion maps were calculated in each region for each subject. Quantitatively on cross-sectional analysis, certain brain regions were preferentially affected by reduced mean diffusivity (parietal, temporal lobes, posterior cingulate, thalamus and deep nuclei, but with relative sparing of the frontal and occipital lobes. Serial imaging, surprisingly showed that mean diffusivity did not have a linear or unidirectional reduction over time, but tended to decrease initially and then reverse and increase towards normalization. Furthermore, there was a strong correlation between worsening of patient clinical function (based on modified Barthel score and increasing mean diffusivity.

  13. Detection of prion infectivity in fat tissues of scrapie-infected mice.

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    Brent Race

    2008-12-01

    Full Text Available Distribution of prion infectivity in organs and tissues is important in understanding prion disease pathogenesis and designing strategies to prevent prion infection in animals and humans. Transmission of prion disease from cattle to humans resulted in banning human consumption of ruminant nervous system and certain other tissues. In the present study, we surveyed tissue distribution of prion infectivity in mice with prion disease. We show for the first time detection of infectivity in white and brown fat. Since high amounts of ruminant fat are consumed by humans and also incorporated into animal feed, fat-containing tissues may pose a previously unappreciated hazard for spread of prion infection.

  14. Neuropathological and biochemical criteria to identify acquired Creutzfeldt-Jakob disease among presumed sporadic cases.

    Science.gov (United States)

    Kobayashi, Atsushi; Parchi, Piero; Yamada, Masahito; Mohri, Shirou; Kitamoto, Tetsuyuki

    2016-06-01

    As an experimental model of acquired Creutzfeldt-Jakob disease (CJD), we performed transmission studies of sporadic CJD using knock-in mice expressing human prion protein (PrP). In this model, the inoculation of the sporadic CJD strain V2 into animals homozygous for methionine at polymorphic codon 129 (129 M/M) of the PRNP gene produced quite distinctive neuropathological and biochemical features, that is, widespread kuru plaques and intermediate type abnormal PrP (PrP(Sc) ). Interestingly, this distinctive combination of molecular and pathological features has been, to date, observed in acquired CJD but not in sporadic CJD. Assuming that these distinctive phenotypic traits are specific for acquired CJD, we revisited the literature and found two cases showing widespread kuru plaques despite the 129 M/M genotype, in a neurosurgeon and in a patient with a medical history of neurosurgery without dura mater grafting. By Western blot analysis of brain homogenates, we revealed the intermediate type of PrP(Sc) in both cases. Furthermore, transmission properties of brain extracts from these two cases were indistinguishable from those of a subgroup of dura mater graft-associated iatrogenic CJD caused by infection with the sporadic CJD strain V2. These data strongly suggest that the two atypical CJD cases, previously thought to represent sporadic CJD, very likely acquired the disease through exposure to prion-contaminated brain tissues. Thus, we propose that the distinctive combination of 129 M/M genotype, kuru plaques, and intermediate type PrP(Sc) , represents a reliable criterion for the identification of acquired CJD cases among presumed sporadic cases. © 2015 Japanese Society of Neuropathology.

  15. Sporadic fatal insomnia in a young woman: A diagnostic challenge: Case Report

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    Cracco Laura

    2011-10-01

    Full Text Available Abstract Background Sporadic fatal insomnia (sFI and fatal familial insomnia (FFI are rare human prion diseases. Case Presentation We report a case of a 33-year-old female who died of a prion disease for whom the diagnosis of sFI or FFI was not considered clinically. Following death of this patient, an interview with a close family member indicated the patient's illness included a major change in her sleep pattern, corroborating the reported autopsy diagnosis of sFI. Genetic tests identified no prion protein (PrP gene mutation, but neuropathological examination and molecular study showed protease-resistant PrP (PrPres in several brain regions and severe atrophy of the anterior-ventral and medial-dorsal thalamic nuclei similar to that described in FFI. Conclusions In patients with suspected prion disease, a characteristic change in sleep pattern can be an important clinical clue for identifying sFI or FFI; polysomnography (PSG, genetic analysis, and nuclear imaging may aid in diagnosis.

  16. S. pombe placed on the prion map

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    Jacqueline Hayles

    2017-02-01

    Full Text Available Schizosaccharomyces pombe has been used extensively as a model organism, however it is only recently that the first prion in this organism, a copper transporter protein encoded by ctr4, has been conclusively demonstrated. Prions are found in a wide range of organisms and have been implicated in a number of human neurodegenerative diseases. Research into the biology of prions has been carried out mainly in the budding yeast Saccharomyces cerevisiae, however there are many questions still to be addressed. Now, with the identification of the Ctr4 prion in S. pombe, further work in the two yeasts and comparisons of prion biology in these organisms should lead to a greater understanding of prions and their role in disease.

  17. Comparative syntheses of peptide thioesters derived from mouse and human prion proteins

    Czech Academy of Sciences Publication Activity Database

    Šebestík, Jaroslav; Zawada, Zbigniew; Šafařík, Martin; Hlaváček, Jan

    2011-01-01

    Roč. 41, Suppl. 1 (2011), S78-S79 ISSN 0939-4451. [International Congress on Amino Acids, Peptides and Proteins /12./. 01.08.2011-05.08.2011, Beijing] R&D Projects: GA ČR GA203/07/1517 Institutional research plan: CEZ:AV0Z40550506 Keywords : peptide thioesters * ligation * prions * C-domain Subject RIV: CC - Organic Chemistry

  18. Molecular architecture of human prion protein amyloid: a parallel, in-register beta-structure.

    Science.gov (United States)

    Cobb, Nathan J; Sönnichsen, Frank D; McHaourab, Hassane; Surewicz, Witold K

    2007-11-27

    Transmissible spongiform encephalopathies (TSEs) represent a group of fatal neurodegenerative diseases that are associated with conformational conversion of the normally monomeric and alpha-helical prion protein, PrP(C), to the beta-sheet-rich PrP(Sc). This latter conformer is believed to constitute the main component of the infectious TSE agent. In contrast to high-resolution data for the PrP(C) monomer, structures of the pathogenic PrP(Sc) or synthetic PrP(Sc)-like aggregates remain elusive. Here we have used site-directed spin labeling and EPR spectroscopy to probe the molecular architecture of the recombinant PrP amyloid, a misfolded form recently reported to induce transmissible disease in mice overexpressing an N-terminally truncated form of PrP(C). Our data show that, in contrast to earlier, largely theoretical models, the con formational conversion of PrP(C) involves major refolding of the C-terminal alpha-helical region. The core of the amyloid maps to C-terminal residues from approximately 160-220, and these residues form single-molecule layers that stack on top of one another with parallel, in-register alignment of beta-strands. This structural insight has important implications for understanding the molecular basis of prion propagation, as well as hereditary prion diseases, most of which are associated with point mutations in the region found to undergo a refolding to beta-structure.

  19. Effect of the electrostatic surface potential on the oligomerization of full-length human recombinant prion protein at single-molecule level

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Bin; Xu, Bingqian, E-mail: bxu@engr.uga.edu [Single Molecule Study Laboratory, College of Engineering and Nanoscale Science, and Engineering Center, University of Georgia, Athens, Georgia 30605 (United States); Lou, Zhichao [Single Molecule Study Laboratory, College of Engineering and Nanoscale Science, and Engineering Center, University of Georgia, Athens, Georgia 30605 (United States); College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Zhang, Haiqian [College of Materials Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

    2016-03-21

    The electrostatic surface potential (ESP) of prion oligomers has critical influences on the aggregating processes of the prion molecules. The atomic force microscopy (AFM) and structural simulation were combined to investigate the molecular basis of the full-length human recombinant prion oligomerization on mica surfaces. The high resolution non-intrusive AFM images showed that the prion oligomers formed different patterns on mica surfaces at different buffer pH values. The basic binding units for the large oligomers were determined to be prion momoners (Ms), dimers (Ds), and trimers (Ts). The forming of the D and T units happened through the binding of hydrophobic β-sheets of the M units. In contrast, the α-helices of these M, D, and T units were the binding areas for the formation of large oligomers. At pH 4.5, the binding units M, D, and T showed clear polarized ESP distributions on the surface domains, while at pH 7.0, they showed more evenly distributed ESPs. Based on the conformations of oligomers observed from AFM images, the D and T units were more abundantly on mica surface at pH 4.5 because the ESP re-distribution of M units helped to stabilize these larger oligomers. The amino acid side chains involved in the binding interfaces were stabilized by hydrogen bonds and electrostatic interactions. The detailed analysis of the charged side chains at pH 4.5 indicated that the polarized ESPs induced the aggregations among M, D, and T to form larger oligomers. Therefore, the hydrogen bonds and electrostatic interactions worked together to form the stabilized prion oligomers.

  20. Effect of the electrostatic surface potential on the oligomerization of full-length human recombinant prion protein at single-molecule level

    International Nuclear Information System (INIS)

    Wang, Bin; Xu, Bingqian; Lou, Zhichao; Zhang, Haiqian

    2016-01-01

    The electrostatic surface potential (ESP) of prion oligomers has critical influences on the aggregating processes of the prion molecules. The atomic force microscopy (AFM) and structural simulation were combined to investigate the molecular basis of the full-length human recombinant prion oligomerization on mica surfaces. The high resolution non-intrusive AFM images showed that the prion oligomers formed different patterns on mica surfaces at different buffer pH values. The basic binding units for the large oligomers were determined to be prion momoners (Ms), dimers (Ds), and trimers (Ts). The forming of the D and T units happened through the binding of hydrophobic β-sheets of the M units. In contrast, the α-helices of these M, D, and T units were the binding areas for the formation of large oligomers. At pH 4.5, the binding units M, D, and T showed clear polarized ESP distributions on the surface domains, while at pH 7.0, they showed more evenly distributed ESPs. Based on the conformations of oligomers observed from AFM images, the D and T units were more abundantly on mica surface at pH 4.5 because the ESP re-distribution of M units helped to stabilize these larger oligomers. The amino acid side chains involved in the binding interfaces were stabilized by hydrogen bonds and electrostatic interactions. The detailed analysis of the charged side chains at pH 4.5 indicated that the polarized ESPs induced the aggregations among M, D, and T to form larger oligomers. Therefore, the hydrogen bonds and electrostatic interactions worked together to form the stabilized prion oligomers.

  1. Effect of the electrostatic surface potential on the oligomerization of full-length human recombinant prion protein at single-molecule level

    Science.gov (United States)

    Wang, Bin; Lou, Zhichao; Zhang, Haiqian; Xu, Bingqian

    2016-03-01

    The electrostatic surface potential (ESP) of prion oligomers has critical influences on the aggregating processes of the prion molecules. The atomic force microscopy (AFM) and structural simulation were combined to investigate the molecular basis of the full-length human recombinant prion oligomerization on mica surfaces. The high resolution non-intrusive AFM images showed that the prion oligomers formed different patterns on mica surfaces at different buffer pH values. The basic binding units for the large oligomers were determined to be prion momoners (Ms), dimers (Ds), and trimers (Ts). The forming of the D and T units happened through the binding of hydrophobic β-sheets of the M units. In contrast, the α-helices of these M, D, and T units were the binding areas for the formation of large oligomers. At pH 4.5, the binding units M, D, and T showed clear polarized ESP distributions on the surface domains, while at pH 7.0, they showed more evenly distributed ESPs. Based on the conformations of oligomers observed from AFM images, the D and T units were more abundantly on mica surface at pH 4.5 because the ESP re-distribution of M units helped to stabilize these larger oligomers. The amino acid side chains involved in the binding interfaces were stabilized by hydrogen bonds and electrostatic interactions. The detailed analysis of the charged side chains at pH 4.5 indicated that the polarized ESPs induced the aggregations among M, D, and T to form larger oligomers. Therefore, the hydrogen bonds and electrostatic interactions worked together to form the stabilized prion oligomers.

  2. The Prion Concept and Synthetic Prions.

    Science.gov (United States)

    Legname, Giuseppe; Moda, Fabio

    2017-01-01

    Transmissible spongiform encephalopathies or prion diseases are a group of fatal neurodegenerative diseases caused by unconventional infectious agents, known as prions (PrP Sc ). Prions derive from a conformational conversion of the normally folded prion protein (PrP C ), which acquires pathological and infectious features. Moreover, PrP Sc is able to transmit the pathological conformation to PrP C through a mechanism that is still not well understood. The generation of synthetic prions, which behave like natural prions, is of fundamental importance to study the process of PrP C conversion and to assess the efficacy of therapeutic strategies to interfere with this process. Moreover, the ability of synthetic prions to induce pathology in animals confirms that the pathological properties of the prion strains are all enciphered in abnormal conformations, characterizing these infectious agents. © 2017 Elsevier Inc. All rights reserved.

  3. Accelerating Yeast Prion Biology using Droplet Microfluidics

    Science.gov (United States)

    Ung, Lloyd; Rotem, Assaf; Jarosz, Daniel; Datta, Manoshi; Lindquist, Susan; Weitz, David

    2012-02-01

    Prions are infectious proteins in a misfolded form, that can induce normal proteins to take the misfolded state. Yeast prions are relevant, as a model of human prion diseases, and interesting from an evolutionary standpoint. Prions may also be a form of epigenetic inheritance, which allow yeast to adapt to stressful conditions at rates exceeding those of random mutations and propagate that adaptation to their offspring. Encapsulation of yeast in droplet microfluidic devices enables high-throughput measurements with single cell resolution, which would not be feasible using bulk methods. Millions of populations of yeast can be screened to obtain reliable measurements of prion induction and loss rates. The population dynamics of clonal yeast, when a fraction of the cells are prion expressing, can be elucidated. Furthermore, the mechanism by which certain strains of bacteria induce yeast to express prions in the wild can be deduced. Integrating the disparate fields of prion biology and droplet microfluidics reveals a more complete picture of how prions may be more than just diseases and play a functional role in yeast.

  4. Prion protein accumulation in lipid rafts of mouse aging brain.

    Directory of Open Access Journals (Sweden)

    Federica Agostini

    Full Text Available The cellular form of the prion protein (PrP(C is a normal constituent of neuronal cell membranes. The protein misfolding causes rare neurodegenerative disorders known as transmissible spongiform encephalopathies or prion diseases. These maladies can be sporadic, genetic or infectious. Sporadic prion diseases are the most common form mainly affecting aging people. In this work, we investigate the biochemical environment in which sporadic prion diseases may develop, focusing our attention on the cell membrane of neurons in the aging brain. It is well established that with aging the ratio between the most abundant lipid components of rafts undergoes a major change: while cholesterol decreases, sphingomyelin content rises. Our results indicate that the aging process modifies the compartmentalization of PrP(C. In old mice, this change favors PrP(C accumulation in detergent-resistant membranes, particularly in hippocampi. To confirm the relationship between lipid content changes and PrP(C translocation into detergent-resistant membranes (DRMs, we looked at PrP(C compartmentalization in hippocampi from acid sphingomyelinase (ASM knockout (KO mice and synaptosomes enriched in sphingomyelin. In the presence of high sphingomyelin content, we observed a significant increase of PrP(C in DRMS. This process is not due to higher levels of total protein and it could, in turn, favor the onset of sporadic prion diseases during aging as it increases the PrP intermolecular contacts into lipid rafts. We observed that lowering sphingomyelin in scrapie-infected cells by using fumonisin B1 led to a 50% decrease in protease-resistant PrP formation. This may suggest an involvement of PrP lipid environment in prion formation and consequently it may play a role in the onset or development of sporadic forms of prion diseases.

  5. Determining the relative susceptibility of four prion protein genotypes to atypical scrapie

    Science.gov (United States)

    Atypical scrapie is a sheep prion (PrPSc) disease whose epidemiology is consistent with a sporadic origin and is associated with specific polymorphisms of the normal cellular prion protein (PrPC). We describe a mass spectrometry-based method of detecting and quantifying the polymorphisms of sheep P...

  6. Detection of prions in blood from patients with variant Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Concha-Marambio, Luis; Pritzkow, Sandra; Moda, Fabio; Tagliavini, Fabrizio; Ironside, James W; Schulz, Paul E; Soto, Claudio

    2016-12-21

    Human prion diseases are infectious and invariably fatal neurodegenerative diseases. They include sporadic Creutzfeldt-Jakob disease (sCJD), the most common form, and variant CJD (vCJD), which is caused by interspecies transmission of prions from cattle infected by bovine spongiform encephalopathy. Development of a biochemical assay for the sensitive, specific, early, and noninvasive detection of prions (PrP Sc ) in the blood of patients affected by prion disease is a top medical priority to increase the safety of the blood supply. vCJD has already been transmitted from human to human by blood transfusion, and the number of asymptomatic carriers of vCJD in the U.K. alone is estimated to be 1 in 2000 people. We used the protein misfolding cyclic amplification (PMCA) technique to analyze blood samples from 14 cases of vCJD and 153 controls, including patients affected by sCJD and other neurodegenerative or neurological disorders as well as healthy subjects. Our results showed that PrP Sc could be detected with 100% sensitivity and specificity in blood samples from vCJD patients. Detection was possible in any of the blood fractions analyzed and could be done with as little as a few microliters of sample volume. The PrP Sc concentration in blood was estimated to be ~0.5 pg/ml. Our findings suggest that PMCA may be useful for premortem noninvasive diagnosis of vCJD and to identify prion contamination of the blood supply. Further studies are needed to fully validate the technology. Copyright © 2016, American Association for the Advancement of Science.

  7. New variant of Creutzfeldt-Jakob (vCJD disease and other human prion diseases under epidemiological surveillance in Brazil

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    Vera Lúcia Gattás

    Full Text Available Abstract To increase the timeliness of detection of human cases of the new variant of Creutzfeldt-Jakob disease (vCJD and to reduce the risk of transmission, the Brazilian Ministry of Health has established and standardized rules and control measures. These include the definition of criteria for suspect cases, reporting, monitoring, and control measures for illness prevention and transmission. Guidelines to be used by the team of health care staff were published and distributed to health workers. A detailed proposal for a simplified system of surveillance for prion diseases was developed and mandatory reporting introduced. Additional effort is necessary to increase vCJD case detection, thus making it necessary to establish a partnership with health care services for best identification of suspected cases and dissemination of information to all involved in the service dealing with vCJD investigation.

  8. Variants of PLCXD3 are not associated with variant or sporadic Creutzfeldt-Jakob disease in a large international study.

    Science.gov (United States)

    Balendra, Rubika; Uphill, James; Collinson, Claire; Druyeh, Ronald; Adamson, Gary; Hummerich, Holger; Zerr, Inga; Gambetti, Pierluigi; Collinge, John; Mead, Simon

    2016-04-07

    Human prion diseases are relentlessly progressive neurodegenerative disorders which include sporadic Creutzfeldt-Jakob disease (sCJD) and variant CJD (vCJD). Aside from variants of the prion protein gene (PRNP) replicated association at genome-wide levels of significance has proven elusive. A recent association study identified variants in or near to the PLCXD3 gene locus as strong disease risk factors in multiple human prion diseases. This study claimed the first non-PRNP locus to be highly significantly associated with prion disease in genomic studies. A sub-study of a genome-wide association study with imputation aiming to replicate the finding at PLCXD3 including 129 vCJD and 2500 sCJD samples. Whole exome sequencing to identify rare coding variants of PLCXD3. Imputation of relevant polymorphisms was accurate based on wet genotyping of a sample. We found no supportive evidence that PLCXD3 variants are associated with disease. The marked discordance in vCJD genotype frequencies between studies, despite extensive overlap in vCJD cases, and the finding of Hardy-Weinberg disequilibrium in the original study, suggests possible reasons for the discrepancies between studies.

  9. Metabolic patterns in prion diseases: an FDG PET voxel-based analysis

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, Elena; Dominguez-Prado, Ines; Jesus Ribelles, Maria; Arbizu, Javier [Clinica Universidad de Navarra, Nuclear Medicine Department, Pamplona (Spain); Riverol, Mario; Ortega-Cubero, Sara; Rosario Luquin, Maria; Castro, Purificacion de [Clinica Universidad de Navarra, Neurology Department, Pamplona (Spain)

    2015-09-15

    Clinical diagnosis of human prion diseases can be challenging since symptoms are common to other disorders associated with rapidly progressive dementia. In this context, {sup 18}F-fluorodeoxyglucose (FDG) positron emission tomography (PET) might be a useful complementary tool. The aim of this study was to determine the metabolic pattern in human prion diseases, particularly sporadic Creutzfeldt-Jakob disease (sCJD), the new variant of Creutzfeldt-Jakob disease (vCJD) and fatal familial insomnia (FFI). We retrospectively studied 17 patients with a definitive, probable or possible prion disease who underwent FDG PET in our institution. Of these patients, 12 were diagnosed as sCJD (9 definitive, 2 probable and 1 possible), 1 was diagnosed as definitive vCJD and 4 were diagnosed as definitive FFI. The hypometabolic pattern of each individual and comparisons across the groups of subjects (control subjects, sCJD and FFI) were evaluated using a voxel-based analysis. The sCJD group exhibited a pattern of hypometabolism that affected both subcortical (bilateral caudate, thalamus) and cortical (frontal cortex) structures, while the FFI group only presented a slight hypometabolism in the thalamus. Individual analysis demonstrated a considerable variability of metabolic patterns among patients, with the thalamus and basal ganglia the most frequently affected areas, combined in some cases with frontal and temporal hypometabolism. Patients with a prion disease exhibit a characteristic pattern of brain metabolism presentation in FDG PET imaging. Consequently, in patients with rapidly progressive cognitive impairment, the detection of these patterns in the FDG PET study could orient the diagnosis to a prion disease. (orig.)

  10. Metabolic patterns in prion diseases: an FDG PET voxel-based analysis

    International Nuclear Information System (INIS)

    Prieto, Elena; Dominguez-Prado, Ines; Jesus Ribelles, Maria; Arbizu, Javier; Riverol, Mario; Ortega-Cubero, Sara; Rosario Luquin, Maria; Castro, Purificacion de

    2015-01-01

    Clinical diagnosis of human prion diseases can be challenging since symptoms are common to other disorders associated with rapidly progressive dementia. In this context, 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) might be a useful complementary tool. The aim of this study was to determine the metabolic pattern in human prion diseases, particularly sporadic Creutzfeldt-Jakob disease (sCJD), the new variant of Creutzfeldt-Jakob disease (vCJD) and fatal familial insomnia (FFI). We retrospectively studied 17 patients with a definitive, probable or possible prion disease who underwent FDG PET in our institution. Of these patients, 12 were diagnosed as sCJD (9 definitive, 2 probable and 1 possible), 1 was diagnosed as definitive vCJD and 4 were diagnosed as definitive FFI. The hypometabolic pattern of each individual and comparisons across the groups of subjects (control subjects, sCJD and FFI) were evaluated using a voxel-based analysis. The sCJD group exhibited a pattern of hypometabolism that affected both subcortical (bilateral caudate, thalamus) and cortical (frontal cortex) structures, while the FFI group only presented a slight hypometabolism in the thalamus. Individual analysis demonstrated a considerable variability of metabolic patterns among patients, with the thalamus and basal ganglia the most frequently affected areas, combined in some cases with frontal and temporal hypometabolism. Patients with a prion disease exhibit a characteristic pattern of brain metabolism presentation in FDG PET imaging. Consequently, in patients with rapidly progressive cognitive impairment, the detection of these patterns in the FDG PET study could orient the diagnosis to a prion disease. (orig.)

  11. Mammalian amyloidogenic proteins promote prion nucleation in yeast.

    Science.gov (United States)

    Chandramowlishwaran, Pavithra; Sun, Meng; Casey, Kristin L; Romanyuk, Andrey V; Grizel, Anastasiya V; Sopova, Julia V; Rubel, Aleksandr A; Nussbaum-Krammer, Carmen; Vorberg, Ina M; Chernoff, Yury O

    2018-03-02

    Fibrous cross-β aggregates (amyloids) and their transmissible forms (prions) cause diseases in mammals (including humans) and control heritable traits in yeast. Initial nucleation of a yeast prion by transiently overproduced prion-forming protein or its (typically, QN-rich) prion domain is efficient only in the presence of another aggregated (in most cases, QN-rich) protein. Here, we demonstrate that a fusion of the prion domain of yeast protein Sup35 to some non-QN-rich mammalian proteins, associated with amyloid diseases, promotes nucleation of Sup35 prions in the absence of pre-existing aggregates. In contrast, both a fusion of the Sup35 prion domain to a multimeric non-amyloidogenic protein and the expression of a mammalian amyloidogenic protein that is not fused to the Sup35 prion domain failed to promote prion nucleation, further indicating that physical linkage of a mammalian amyloidogenic protein to the prion domain of a yeast protein is required for the nucleation of a yeast prion. Biochemical and cytological approaches confirmed the nucleation of protein aggregates in the yeast cell. Sequence alterations antagonizing or enhancing amyloidogenicity of human amyloid-β (associated with Alzheimer's disease) and mouse prion protein (associated with prion diseases), respectively, antagonized or enhanced nucleation of a yeast prion by these proteins. The yeast-based prion nucleation assay, developed in our work, can be employed for mutational dissection of amyloidogenic proteins. We anticipate that it will aid in the identification of chemicals that influence initial amyloid nucleation and in searching for new amyloidogenic proteins in a variety of proteomes. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  12. Prion pathogenesis and secondary lymphoid organs (SLO)

    Science.gov (United States)

    Mabbott, Neil A.

    2012-01-01

    Prion diseases are subacute neurodegenerative diseases that affect humans and a range of domestic and free-ranging animal species. These diseases are characterized by the accumulation of PrPSc, an abnormally folded isoform of the cellular prion protein (PrPC), in affected tissues. The pathology during prion disease appears to occur almost exclusively within the central nervous system. The extensive neurodegeneration which occurs ultimately leads to the death of the host. An intriguing feature of the prion diseases, when compared with other protein-misfolding diseases, is their transmissibility. Following peripheral exposure, some prion diseases accumulate to high levels within lymphoid tissues. The replication of prions within lymphoid tissue has been shown to be important for the efficient spread of disease to the brain. This article describes recent progress in our understanding of the cellular mechanisms that influence the propagation of prions from peripheral sites of exposure (such as the lumen of the intestine) to the brain. A thorough understanding of these events will lead to the identification of important targets for therapeutic intervention, or alternatively, reveal additional processes that influence disease susceptibility to peripherally-acquired prion diseases. PMID:22895090

  13. Gene expression profiling for human iPS-derived motor neurons from sporadic ALS patients reveals a strong association between mitochondrial functions and neurodegeneration

    Science.gov (United States)

    Alves, Chrystian J.; Dariolli, Rafael; Jorge, Frederico M.; Monteiro, Matheus R.; Maximino, Jessica R.; Martins, Roberto S.; Strauss, Bryan E.; Krieger, José E.; Callegaro, Dagoberto; Chadi, Gerson

    2015-01-01

    Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease that leads to widespread motor neuron death, general palsy and respiratory failure. The most prevalent sporadic ALS form is not genetically inherited. Attempts to translate therapeutic strategies have failed because the described mechanisms of disease are based on animal models carrying specific gene mutations and thus do not address sporadic ALS. In order to achieve a better approach to study the human disease, human induced pluripotent stem cell (hiPSC)-differentiated motor neurons were obtained from motor nerve fibroblasts of sporadic ALS and non-ALS subjects using the STEMCCA Cre-Excisable Constitutive Polycistronic Lentivirus system and submitted to microarray analyses using a whole human genome platform. DAVID analyses of differentially expressed genes identified molecular function and biological process-related genes through Gene Ontology. REVIGO highlighted the related functions mRNA and DNA binding, GTP binding, transcription (co)-repressor activity, lipoprotein receptor binding, synapse organization, intracellular transport, mitotic cell cycle and cell death. KEGG showed pathways associated with Parkinson's disease and oxidative phosphorylation, highlighting iron homeostasis, neurotrophic functions, endosomal trafficking and ERK signaling. The analysis of most dysregulated genes and those representative of the majority of categorized genes indicates a strong association between mitochondrial function and cellular processes possibly related to motor neuron degeneration. In conclusion, iPSC-derived motor neurons from motor nerve fibroblasts of sporadic ALS patients may recapitulate key mechanisms of neurodegeneration and may offer an opportunity for translational investigation of sporadic ALS. Large gene profiling of differentiated motor neurons from sporadic ALS patients highlights mitochondrial participation in the establishment of autonomous mechanisms associated with sporadic ALS

  14. Experimental Models of Inherited PrP Prion Diseases.

    Science.gov (United States)

    Watts, Joel C; Prusiner, Stanley B

    2017-11-01

    The inherited prion protein (PrP) prion disorders, which include familial Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker disease, and fatal familial insomnia, constitute ∼10%-15% of all PrP prion disease cases in humans. Attempts to generate animal models of these disorders using transgenic mice expressing mutant PrP have produced variable results. Although many lines of mice develop spontaneous signs of neurological illness with accompanying prion disease-specific neuropathological changes, others do not. Furthermore, demonstrating the presence of protease-resistant PrP species and prion infectivity-two of the hallmarks of the PrP prion disorders-in the brains of spontaneously sick mice has proven particularly challenging. Here, we review the progress that has been made toward developing accurate mouse models of the inherited PrP prion disorders. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  15. Prions and prion-like proteins.

    Science.gov (United States)

    Fraser, Paul E

    2014-07-18

    Prions are self-replicating protein aggregates and are the primary causative factor in a number of neurological diseases in mammals. The prion protein (PrP) undergoes a conformational transformation leading to aggregation into an infectious cellular pathogen. Prion-like protein spreading and transmission of aggregates between cells have also been demonstrated for other proteins associated with Alzheimer disease and Parkinson disease. This protein-only phenomenon may therefore have broader implications in neurodegenerative disorders. The minireviews in this thematic series highlight the recent advances in prion biology and the roles these unique proteins play in disease. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Bioinformatic Analysis of Deleterious Non-Synonymous Single Nucleotide Polymorphisms (nsSNPs in the Coding Regions of Human Prion Protein Gene (PRNP

    Directory of Open Access Journals (Sweden)

    Kourosh Bamdad

    2016-12-01

    Full Text Available Background & Objective: Single nucleotide polymorphisms are the cause of genetic variation to living organisms. Single nucleotide polymorphisms alter residues in the protein sequence. In this investigation, the relationship between prion protein gene polymorphisms and its relevance to pathogenicity was studied. Material & Method: Amino acid sequence of the main isoform from the human prion protein gene (PRNP was extracted from UniProt database and evaluated by FoldAmyloid and AmylPred servers. All non-synonymous single nucleotide polymorphisms (nsSNPs from SNP database (dbSNP were further analyzed by bioinformatics servers including SIFT, PolyPhen-2, I-Mutant-3.0, PANTHER, SNPs & GO, PHD-SNP, Meta-SNP, and MutPred to determine the most damaging nsSNPs. Results: The results of the first structure analyses by FoldAmyloid and AmylPerd servers implied that regions including 5-15, 174-178, 180-184, 211-217, and 240-252 were the most sensitive parts of the protein sequence to amyloidosis. Screening all nsSNPs of the main protein isoform using bioinformatic servers revealed that substitution of Aspartic acid with Valine at position 178 (ID code: rs11538766 was the most deleterious nsSNP in the protein structure. Conclusion:  Substitution of the Aspartic acid with Valine at position 178 (D178V was the most pathogenic mutation in the human prion protein gene. Analyses from the MutPred server also showed that beta-sheets’ increment in the secondary structure was the main reason behind the molecular mechanism of the prion protein aggregation.

  17. PrionScan: an online database of predicted prion domains in complete proteomes.

    Science.gov (United States)

    Espinosa Angarica, Vladimir; Angulo, Alfonso; Giner, Arturo; Losilla, Guillermo; Ventura, Salvador; Sancho, Javier

    2014-02-05

    Prions are a particular type of amyloids related to a large variety of important processes in cells, but also responsible for serious diseases in mammals and humans. The number of experimentally characterized prions is still low and corresponds to a handful of examples in microorganisms and mammals. Prion aggregation is mediated by specific protein domains with a remarkable compositional bias towards glutamine/asparagine and against charged residues and prolines. These compositional features have been used to predict new prion proteins in the genomes of different organisms. Despite these efforts, there are only a few available data sources containing prion predictions at a genomic scale. Here we present PrionScan, a new database of predicted prion-like domains in complete proteomes. We have previously developed a predictive methodology to identify and score prionogenic stretches in protein sequences. In the present work, we exploit this approach to scan all the protein sequences in public databases and compile a repository containing relevant information of proteins bearing prion-like domains. The database is updated regularly alongside UniprotKB and in its present version contains approximately 28000 predictions in proteins from different functional categories in more than 3200 organisms from all the taxonomic subdivisions. PrionScan can be used in two different ways: database query and analysis of protein sequences submitted by the users. In the first mode, simple queries allow to retrieve a detailed description of the properties of a defined protein. Queries can also be combined to generate more complex and specific searching patterns. In the second mode, users can submit and analyze their own sequences. It is expected that this database would provide relevant insights on prion functions and regulation from a genome-wide perspective, allowing researches performing cross-species prion biology studies. Our database might also be useful for guiding experimentalists

  18. Prion disease. The characteristics and diagnostic points in Japan

    International Nuclear Information System (INIS)

    Sanjo, Nobuo; Mizusawa, Hidehiro

    2010-01-01

    Prion disease develops when normal prion proteins change into transmissible abnormal prion proteins and the converted proteins accumulate in the brain. The Japanese Creutzfeldt-Jakob Disease (CJD) Surveillance Committee has identified 1,320 patients with prion diseases in the 10 years since 1999 (classified into 3 types: sporadic, 77.2%; hereditary, 16.7%; and environmentally acquired, 6.1%). Compared with patients in other countries, a relatively larger number of Japanese patients characteristically have dura mater graft-associated CJD and hereditary prion diseases. All the environmentally acquired cases, except 1 case of variant CJD, were acquired from dura grafts. Although most patients were diagnosed with a classical subtype of sporadic CJD (sCJD), whose features include rapidly progressing dementia, myoclonus, hyperintensity in the cerebral cortex and basal ganglia in diffusion-weighted magnetic resonance imaging, and periodic synchronous discharge in electroencephalography, the number of cases with atypical symptoms, such as MM2 (0.8%), MV2 (0.2%), VV1 (0%), and VV2 (0.2%) subtypes of sCJD cases, was not negligible. Appropriate diagnosis should be made based on clinical features, neuroradiological findings, cerebrospinal fluid (CSF) findings (14-3-3 and total tau proteins), and genetic analysis of polymorphisms. Hereditary prion diseases are classified into 3 major phenotypes: familial CJD (fCJD); Gerstmann-Straeussler-Scheinker disease (GSS), which mainly presents as spinocerebellar ataxia; and fatal familial insomnia. Many mutations of the prion protein gene have been identified, but V1801 (fCJD), P102L (GSS), and E200K (fCJD) mutations were the most common among the fCJD cases in Japan. Without a family history, genetic testing is necessary to distinguish even seemingly ''sporadic'' CJD from fCJD. Accurate diagnosis is important for clarification of the pathological process, prevention of secondary infection, and also psychological support. (author)

  19. Removal process of prion and parvovirus from human platelet lysates used as clinical-grade supplement for ex vivo cell expansion.

    Science.gov (United States)

    Kao, Yu-Chun; Bailey, Andy; Samminger, Bernhard; Tanimoto, Junji; Burnouf, Thierry

    2016-07-01

    Pooled human platelet lysate (HPL) is becoming the new gold standard as supplement for ex vivo cell culture for clinical protocols. However, the risk of pathogen contamination of HPL increases with the platelet pool size. We hypothesized that hollow fiber anion exchange membrane chromatography using QyuSpeed D (QSD) could remove resistant and untested bloodborne pathogens, such as parvoviruses and prions, from HPL-supplemented growth media without substantially affecting their capacity to support ex vivo cell expansion. Frozen or thawed platelet concentrates were serum-converted and centrifuged for obtaining HPL that was added to various growth media (ca. 100 mL), filtered through a 0.6-mL QSD membrane and characterized for proteins, growth factors and chemical composition. Capacity to expand Chinese hamster ovary, periodontal ligament, gingival fibroblast cells and Wharton's jelly mesenchymal stromal cells was studied. Removal of porcine parvovirus (PPV) and of the 263K prion strain of hamster-adapted scrapie was studied by spiking experiments following international guidelines. QSD had minimal impact on HPL-supplemented medium composition in proteins, growth factors and chemical content, nor capacity to expand and differentiate cells. In addition, QSD could remove ≥5.58 log10 [TCID50/mL] and ≥3.72 log10 of PPV and the 263K prion, respectively. QSD hollow fiber chromatography can be used to improve the virus and prion safety of HPL-supplemented media to safely expand cells for clinical protocols. These data bring new perspectives for increasingly safer use of pooled HPL in cell therapy and regenerative medicine applications. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  20. Protease resistance of infectious prions is suppressed by removal of a single atom in the cellular prion protein.

    Science.gov (United States)

    Leske, Henning; Hornemann, Simone; Herrmann, Uli Simon; Zhu, Caihong; Dametto, Paolo; Li, Bei; Laferriere, Florent; Polymenidou, Magdalini; Pelczar, Pawel; Reimann, Regina Rose; Schwarz, Petra; Rushing, Elisabeth Jane; Wüthrich, Kurt; Aguzzi, Adriano

    2017-01-01

    Resistance to proteolytic digestion has long been considered a defining trait of prions in tissues of organisms suffering from transmissible spongiform encephalopathies. Detection of proteinase K-resistant prion protein (PrPSc) still represents the diagnostic gold standard for prion diseases in humans, sheep and cattle. However, it has become increasingly apparent that the accumulation of PrPSc does not always accompany prion infections: high titers of prion infectivity can be reached also in the absence of protease resistant PrPSc. Here, we describe a structural basis for the phenomenon of protease-sensitive prion infectivity. We studied the effect on proteinase K (PK) resistance of the amino acid substitution Y169F, which removes a single oxygen atom from the β2-α2 loop of the cellular prion protein (PrPC). When infected with RML or the 263K strain of prions, transgenic mice lacking wild-type (wt) PrPC but expressing MoPrP169F generated prion infectivity at levels comparable to wt mice. The newly generated MoPrP169F prions were biologically indistinguishable from those recovered from prion-infected wt mice, and elicited similar pathologies in vivo. Surprisingly, MoPrP169F prions showed greatly reduced PK resistance and density gradient analyses showed a significant reduction in high-density aggregates. Passage of MoPrP169F prions into mice expressing wt MoPrP led to full recovery of protease resistance, indicating that no strain shift had taken place. We conclude that a subtle structural variation in the β2-α2 loop of PrPC affects the sensitivity of PrPSc to protease but does not impact prion replication and infectivity. With these findings a specific structural feature of PrPC can be linked to a physicochemical property of the corresponding PrPSc.

  1. Epigenetic dominance of prion conformers.

    Directory of Open Access Journals (Sweden)

    Eri Saijo

    2013-10-01

    Full Text Available Although they share certain biological properties with nucleic acid based infectious agents, prions, the causative agents of invariably fatal, transmissible neurodegenerative disorders such as bovine spongiform encephalopathy, sheep scrapie, and human Creutzfeldt Jakob disease, propagate by conformational templating of host encoded proteins. Once thought to be unique to these diseases, this mechanism is now recognized as a ubiquitous means of information transfer in biological systems, including other protein misfolding disorders such as those causing Alzheimer's and Parkinson's diseases. To address the poorly understood mechanism by which host prion protein (PrP primary structures interact with distinct prion conformations to influence pathogenesis, we produced transgenic (Tg mice expressing different sheep scrapie susceptibility alleles, varying only at a single amino acid at PrP residue 136. Tg mice expressing ovine PrP with alanine (A at (OvPrP-A136 infected with SSBP/1 scrapie prions propagated a relatively stable (S prion conformation, which accumulated as punctate aggregates in the brain, and produced prolonged incubation times. In contrast, Tg mice expressing OvPrP with valine (V at 136 (OvPrP-V136 infected with the same prions developed disease rapidly, and the converted prion was comprised of an unstable (U, diffusely distributed conformer. Infected Tg mice co-expressing both alleles manifested properties consistent with the U conformer, suggesting a dominant effect resulting from exclusive conversion of OvPrP-V136 but not OvPrP-A136. Surprisingly, however, studies with monoclonal antibody (mAb PRC5, which discriminates OvPrP-A136 from OvPrP-V136, revealed substantial conversion of OvPrP-A136. Moreover, the resulting OvPrP-A136 prion acquired the characteristics of the U conformer. These results, substantiated by in vitro analyses, indicated that co-expression of OvPrP-V136 altered the conversion potential of OvPrP-A136 from the S to

  2. MM2-thalamic Creutzfeldt-Jakob disease: neuropathological, biochemical and transmission studies identify a distinctive prion strain.

    Science.gov (United States)

    Moda, Fabio; Suardi, Silvia; Di Fede, Giuseppe; Indaco, Antonio; Limido, Lucia; Vimercati, Chiara; Ruggerone, Margherita; Campagnani, Ilaria; Langeveld, Jan; Terruzzi, Alessandro; Brambilla, Antonio; Zerbi, Pietro; Fociani, Paolo; Bishop, Matthew T; Will, Robert G; Manson, Jean C; Giaccone, Giorgio; Tagliavini, Fabrizio

    2012-09-01

    In Creutzfeldt-Jakob disease (CJD), molecular typing based on the size of the protease resistant core of the disease-associated prion protein (PrP(Sc) ) and the M/V polymorphism at codon 129 of the PRNP gene correlates with the clinico-pathologic subtypes. Approximately 95% of the sporadic 129MM CJD patients are characterized by cerebral deposition of type 1 PrP(Sc) and correspond to the classic clinical CJD phenotype. The rare 129MM CJD patients with type 2 PrP(Sc) are further subdivided in a cortical and a thalamic form also indicated as sporadic fatal insomnia. We observed two young patients with MM2-thalamic CJD. Main neuropathological features were diffuse, synaptic PrP immunoreactivity in the cerebral cortex and severe neuronal loss and gliosis in the thalamus and olivary nucleus. Western blot analysis showed the presence of type 2A PrP(Sc) . Challenge of transgenic mice expressing 129MM human PrP showed that MM2-thalamic sporadic CJD (sCJD) was able to transmit the disease, at variance with MM2-cortical sCJD. The affected mice showed deposition of type 2A PrP(Sc) , a scenario that is unprecedented in this mouse line. These data indicate that MM2-thalamic sCJD is caused by a prion strain distinct from the other sCJD subtypes including the MM2-cortical form. © 2012 The Authors; Brain Pathology © 2012 International Society of Neuropathology.

  3. Prion pathogenesis and secondary lymphoid organs (SLO): tracking the SLO spread of prions to the brain.

    Science.gov (United States)

    Mabbott, Neil A

    2012-01-01

    Prion diseases are subacute neurodegenerative diseases that affect humans and a range of domestic and free-ranging animal species. These diseases are characterized by the accumulation of PrP (Sc), an abnormally folded isoform of the cellular prion protein (PrP (C)), in affected tissues. The pathology during prion disease appears to occur almost exclusively within the central nervous system. The extensive neurodegeneration which occurs ultimately leads to the death of the host. An intriguing feature of the prion diseases, when compared with other protein-misfolding diseases, is their transmissibility. Following peripheral exposure, some prion diseases accumulate to high levels within lymphoid tissues. The replication of prions within lymphoid tissue has been shown to be important for the efficient spread of disease to the brain. This article describes recent progress in our understanding of the cellular mechanisms that influence the propagation of prions from peripheral sites of exposure (such as the lumen of the intestine) to the brain. A thorough understanding of these events will lead to the identification of important targets for therapeutic intervention, or alternatively, reveal additional processes that influence disease susceptibility to peripherally-acquired prion diseases.

  4. Prions and lymphoid organs

    Science.gov (United States)

    O’Connor, Tracy; Aguzzi, Adriano

    2013-01-01

    Prion colonization of secondary lymphoid organs (SLOs) is a critical step preceding neuroinvasion in prion pathogenesis. Follicular dendritic cells (FDCs), which depend on both tumor necrosis factor receptor 1 (TNFR1) and lymphotoxin β receptor (LTβR) signaling for maintenance, are thought to be the primary sites of prion accumulation in SLOs. However, prion titers in RML-infected TNFR1−/− lymph nodes and rates of neuroinvasion in TNFR1−/− mice remain high despite the absence of mature FDCs. Recently, we discovered that TNFR1-independent prion accumulation in lymph nodes relies on LTβR signaling. Loss of LTβR signaling in TNFR1−/− lymph nodes coincided with the de-differentiation of high endothelial venules (HEVs)—the primary sites of lymphocyte entry into lymph nodes. These findings suggest that HEVs are the sites through which prions initially invade lymph nodes from the bloodstream. Identification of HEVs as entry portals for prions clarifies a number of previous observations concerning peripheral prion pathogenesis. However, a number of questions still remain: What is the mechanism by which prions are taken up by HEVs? Which cells are responsible for delivering prions to lymph nodes? Are HEVs the main entry site for prions into lymph nodes or do alternative routes also exist? These questions and others are considered in this article. PMID:23357827

  5. Preclinical deposition of pathological prion protein in muscle of experimentally infected primates.

    Directory of Open Access Journals (Sweden)

    Susanne Krasemann

    Full Text Available Prion diseases are transmissible fatal neurodegenerative disorders affecting humans and animals. A central step in disease progression is the accumulation of a misfolded form (PrP(Sc of the host encoded prion protein (PrP(C in neuronal and non-neuronal tissues. The involvement of peripheral tissues in preclinical states increases the risk of accidental transmission. On the other hand, detection of PrP(Sc in non-neuronal easy-accessible compartments such as muscle may offer a novel diagnostic tool. Primate models have proven invaluable to investigate prion diseases. We have studied the deposition of PrP(Sc in muscle and central nervous system of rhesus monkeys challenged with sporadic Creutzfeldt-Jakob disease (sCJD, variant CJD (vCJD and bovine spongiform encephalopathy (BSE in preclinical and clinical stage using biochemical and morphological methods. Here, we show the preclinical presence of PrP(Sc in muscle and central nervous system of rhesus monkeys experimentally infected with vCJD.

  6. Prion-based memory of heat stress in yeast.

    Science.gov (United States)

    Chernova, Tatiana A; Chernoff, Yury O; Wilkinson, Keith D

    2017-05-04

    Amyloids and amyloid-based prions are self-perpetuating protein aggregates which can spread by converting a normal protein of the same sequence into a prion form. They are associated with diseases in humans and mammals, and control heritable traits in yeast and other fungi. Some amyloids are implicated in biologically beneficial processes. As prion formation generates reproducible memory of a conformational change, prions can be considered as molecular memory devices.  We have demonstrated that in yeast, stress-inducible cytoskeleton-associated protein Lsb2 forms a metastable prion in response to high temperature. This prion promotes conversion of other proteins into prions and can persist in a fraction of cells for a significant number of cell generations after stress, thus maintaining the memory of stress in a population of surviving cells. Acquisition of an amino acid substitution required for Lsb2 to form a prion coincides with acquisition of increased thermotolerance in the evolution of Saccharomyces yeast. Thus the ability to form an Lsb2 prion in response to stress coincides with yeast adaptation to growth at higher temperatures. These findings intimately connect prion formation to the cellular response to environmental stresses.

  7. Advancing prion science: guidance for the National Prion Research Program

    National Research Council Canada - National Science Library

    Erdtmann, Rick; Sivitz, Laura

    2004-01-01

    ...€™s National Prion Research Program (NPRP). Transmissible spongiform encephalopathies (TSEs), also called prion diseases, are invariably fatal neurodegenerative infectious diseases that include bovine spongiform encephalopathy...

  8. Immunology of Prion Protein and Prions.

    Science.gov (United States)

    Mabbott, Neil A

    2017-01-01

    Many natural prion diseases are acquired peripherally, such as following the oral consumption of contaminated food or pasture. After peripheral exposure many prion isolates initially accumulate to high levels within the host's secondary lymphoid tissues. The replication of prions within these tissues is essential for their efficient spread to the brain where they ultimately cause neurodegeneration. This chapter describes our current understanding of the critical tissues, cells, and molecules which the prions exploit to mediate their efficient propagation from the site of exposure (such as the intestine) to the brain. Interactions between the immune system and prions are not only restricted to the secondary lymphoid tissues. Therefore, an account of how the activation status of the microglial in the brain can also influence progression of prion disease pathogenesis is provided. Prion disease susceptibility may also be influenced by additional factors such as chronic inflammation, coinfection with other pathogens, and aging. Finally, the potential for immunotherapy to provide a means of safe and effective prophylactic or therapeutic intervention in these currently untreatable diseases is considered. © 2017 Elsevier Inc. All rights reserved.

  9. Source attribution of human salmonellosis and campylobacteriosos using a systematic review of studies of sporadic infections

    DEFF Research Database (Denmark)

    Coutinho Calado Domingues, Ana Rita; Pires, Sara Monteiro; Hald, Tine

    Salmonella spp. and Campylobacter spp. are widespread and important causes of human illness worldwide. Disease is most frequently associated with foodborne transmission, but other routes of exposure, such as direct contact with live animals and person-to-person transmission, are recognized. Ident...

  10. Protease-sensitive conformers in broad spectrum of distinct PrPSc structures in sporadic Creutzfeldt-Jakob disease are indicator of progression rate.

    Directory of Open Access Journals (Sweden)

    Chae Kim

    2011-09-01

    Full Text Available The origin, range, and structure of prions causing the most common human prion disease, sporadic Creutzfeldt-Jakob disease (sCJD, are largely unknown. To investigate the molecular mechanism responsible for the broad phenotypic variability of sCJD, we analyzed the conformational characteristics of protease-sensitive and protease-resistant fractions of the pathogenic prion protein (PrP(Sc using novel conformational methods derived from a conformation-dependent immunoassay (CDI. In 46 brains of patients homozygous for polymorphisms in the PRNP gene and exhibiting either Type 1 or Type 2 western blot pattern of the PrP(Sc, we identified an extensive array of PrP(Sc structures that differ in protease sensitivity, display of critical domains, and conformational stability. Surprisingly, in sCJD cases homozygous for methionine or valine at codon 129 of the PRNP gene, the concentration and stability of protease-sensitive conformers of PrP(Sc correlated with progression rate of the disease. These data indicate that sCJD brains exhibit a wide spectrum of PrP(Sc structural states, and accordingly argue for a broad spectrum of prion strains coding for different phenotypes. The link between disease duration, levels, and stability of protease-sensitive conformers of PrP(Sc suggests that these conformers play an important role in the pathogenesis of sCJD.

  11. Chronic wasting disease and atypical forms of bovine spongiform encephalopathy and scrapie are not transmissible to mice expressing wild-type levels of human prion protein.

    Science.gov (United States)

    Wilson, Rona; Plinston, Chris; Hunter, Nora; Casalone, Cristina; Corona, Cristiano; Tagliavini, Fabrizio; Suardi, Silvia; Ruggerone, Margherita; Moda, Fabio; Graziano, Silvia; Sbriccoli, Marco; Cardone, Franco; Pocchiari, Maurizio; Ingrosso, Loredana; Baron, Thierry; Richt, Juergen; Andreoletti, Olivier; Simmons, Marion; Lockey, Richard; Manson, Jean C; Barron, Rona M

    2012-07-01

    The association between bovine spongiform encephalopathy (BSE) and variant Creutzfeldt-Jakob disease (vCJD) has demonstrated that cattle transmissible spongiform encephalopathies (TSEs) can pose a risk to human health and raises the possibility that other ruminant TSEs may be transmissible to humans. In recent years, several novel TSEs in sheep, cattle and deer have been described and the risk posed to humans by these agents is currently unknown. In this study, we inoculated two forms of atypical BSE (BASE and H-type BSE), a chronic wasting disease (CWD) isolate and seven isolates of atypical scrapie into gene-targeted transgenic (Tg) mice expressing the human prion protein (PrP). Upon challenge with these ruminant TSEs, gene-targeted Tg mice expressing human PrP did not show any signs of disease pathology. These data strongly suggest the presence of a substantial transmission barrier between these recently identified ruminant TSEs and humans.

  12. Computational Calculation Of The Ionization Energies Of The Human Prion Protein By The Coarse-grain Method

    Science.gov (United States)

    Lyu, Justin; Andrianarijaona, V. M.

    2016-05-01

    The causes of the misfolding of prion protein -i.e. the transformation of PrPC to PrPSc - have not been clearly elucidated. Many studies have focused on identifying possible chemical conditions, such as pH, temperature and chemical denaturation, that may trigger the pathological transformation of prion proteins (Weiwei Tao, Gwonchan Yoon, Penghui Cao, `` β-sheet-like formation during the mechanical unfolding of prion protein'', The Journal of Chemical Physics, 2015, 143, 125101). Here, we attempt to calculate the ionization energies of the prion protein, which will be able to shed light onto the possible causes of the misfolding. We plan on using the coarse-grain method which allows for a more feasible calculation time by means of approximation. We believe that by being able to approximate the ionization potential, particularly that of the regions known to form stable β-strands of the PrPSc form, the possible sources of denaturation, be it chemical or mechanical, may be narrowed down.

  13. Incidence and spectrum of sporadic Creutzfeldt-Jakob disease variants with mixed phenotype and co-occurrence of PrPSc types: an updated classification

    NARCIS (Netherlands)

    Parchi, P.; Strammiello, R.; Notari, S.; Giese, A.; Langeveld, J.P.M.; Ladogana, A.; Zerr, I.; Roncaroli, F.; Cras, P.; Ghetti, B.; Pocchiari, M.; Kretzschmar, H.; Capellari, S.

    2009-01-01

    Six subtypes of sporadic Creutzfeldt-Jakob disease with distinctive clinico-pathological features have been identified largely based on two types of the abnormal prion protein, PrPSc, and the methionine (M)/valine (V) polymorphic codon 129 of the prion protein. The existence of affected subjects

  14. Insights into mechanisms of transmission and pathogenesis from transgenic mouse models of prion diseases

    Science.gov (United States)

    Moreno, Julie A.; Telling, Glenn C.

    2018-01-01

    Prions represent a new paradigm of protein-mediated information transfer. In the case of mammals, prions are the cause of fatal, transmissible neurodegenerative diseases, sometimes referred to as transmissible spongiform encephalopathies (TSE’s), which frequently occur as epidemics. An increasing body of evidence indicates that the canonical mechanism of conformational corruption of cellular prion protein (PrPC) by the pathogenic isoform (PrPSc) that is the basis of prion formation in TSE’s, is common to a spectrum of proteins associated with various additional human neurodegenerative disorders, including the more common Alzheimer’s and Parkinson’s diseases. The peerless infectious properties of TSE prions, and the unparalleled tools for their study, therefore enable elucidation of mechanisms of template-mediated conformational propagation that are generally applicable to these related disease states. Many unresolved issues remain including the exact molecular nature of the prion, the detailed cellular and molecular mechanisms of prion propagation, and the means by which prion diseases can be both genetic and infectious. In addition, we know little about the mechanism by which neurons degenerate during prion diseases. Tied to this, the physiological role of the normal form of the prion protein remains unclear and it is uncertain whether or not loss of this function contributes to prion pathogenesis. The factors governing the transmission of prions between species remain unclear, in particular the means by which prion strains and PrP primary structure interact to affect inter-species prion transmission. Despite all these unknowns, advances in our understanding of prions have occurred because of their transmissibility to experimental animals and the development of transgenic (Tg) mouse models has done much to further our understanding about various aspects of prion biology. In this review we will focus on advances in our understanding of prion biology that

  15. Ultraviolet-ozone treatment reduces levels of disease-associated prion protein and prion infectivity

    Science.gov (United States)

    Johnson, C.J.; Gilbert, P.; McKenzie, D.; Pedersen, J.A.; Aiken, Judd M.

    2009-01-01

    Background. Transmissible spongiform encephalopathies (TSEs) are a group of fatal neurodegenerative diseases caused by novel infectious agents referred to as prions. Prions appear to be composed primarily, if not exclusively, of a misfolded isoform of the cellular prion protein. TSE infectivity is remarkably stable and can resist many aggressive decontamination procedures, increasing human, livestock and wildlife exposure to TSEs. Findings. We tested the hypothesis that UV-ozone treatment reduces levels of the pathogenic prion protein and inactivates the infectious agent. We found that UV-ozone treatment decreased the carbon and prion protein content in infected brain homogenate to levels undetectable by dry-ashing carbon analysis or immunoblotting, respectively. After 8 weeks of ashing, UV-ozone treatment reduced the infectious titer of treated material by a factor of at least 105. A small amount of infectivity, however, persisted despite UV-ozone treatment. When bound to either montmorillonite clay or quartz surfaces, PrPTSE was still susceptible to degradation by UV-ozone. Conclusion. Our findings strongly suggest that UV-ozone treatment can degrade pathogenic prion protein and inactivate prions, even when the agent is associated with surfaces. Using larger UV-ozone doses or combining UV-ozone treatment with other decontaminant methods may allow the sterilization of TSE-contaminated materials. ?? 2009 Aiken et al; licensee BioMed Central Ltd.

  16. Structural characterization of POM6 Fab and mouse prion protein complex identifies key regions for prions conformational conversion.

    Science.gov (United States)

    Baral, Pravas Kumar; Swayampakula, Mridula; Aguzzi, Adriano; James, Michael N G

    2018-05-01

    Conversion of the cellular prion protein PrP C into its pathogenic isoform PrP S c is the hallmark of prion diseases, fatal neurodegenerative diseases affecting many mammalian species including humans. Anti-prion monoclonal antibodies can arrest the progression of prion diseases by stabilizing the cellular form of the prion protein. Here, we present the crystal structure of the POM6 Fab fragment, in complex with the mouse prion protein (moPrP). The prion epitope of POM6 is in close proximity to the epitope recognized by the purportedly toxic antibody fragment, POM1 Fab also complexed with moPrP. The POM6 Fab recognizes a larger binding interface indicating a likely stronger binding compared to POM1. POM6 and POM1 exhibit distinct biological responses. Structural comparisons of the bound mouse prion proteins from the POM6 Fab:moPrP and POM1 Fab:moPrP complexes reveal several key regions of the prion protein that might be involved in initiating mis-folding events. The structural data of moPrP:POM6 Fab complex are available in the PDB under the accession number www.rcsb.org/pdb/search/structidSearch.do?structureId=6AQ7. © 2018 Federation of European Biochemical Societies.

  17. The celecoxib derivatives AR-12 and AR-14 induce autophagy and clear prion-infected cells from prions.

    Science.gov (United States)

    Abdulrahman, Basant A; Abdelaziz, Dalia; Thapa, Simrika; Lu, Li; Jain, Shubha; Gilch, Sabine; Proniuk, Stefan; Zukiwski, Alexander; Schatzl, Hermann M

    2017-12-14

    Prion diseases are fatal infectious neurodegenerative disorders that affect both humans and animals. The autocatalytic conversion of the cellular prion protein (PrP C ) into the pathologic isoform PrP Sc is a key feature in prion pathogenesis. AR-12 is an IND-approved derivative of celecoxib that demonstrated preclinical activity against several microbial diseases. Recently, AR-12 has been shown to facilitate clearance of misfolded proteins. The latter proposes AR-12 to be a potential therapeutic agent for neurodegenerative disorders. In this study, we investigated the role of AR-12 and its derivatives in controlling prion infection. We tested AR-12 in prion infected neuronal and non-neuronal cell lines. Immunoblotting and confocal microscopy results showed that AR-12 and its analogue AR-14 reduced PrP Sc levels after only 72 hours of treatment. Furthermore, infected cells were cured of PrP Sc after exposure of AR-12 or AR-14 for only two weeks. We partially attribute the influence of the AR compounds on prion propagation to autophagy stimulation, in line with our previous findings that drug-induced stimulation of autophagy has anti-prion effects in vitro and in vivo. Taken together, this study demonstrates that AR-12 and the AR-14 analogue are potential new therapeutic agents for prion diseases and possibly protein misfolding disorders involving prion-like mechanisms.

  18. Functional diversification of hsp40: distinct j-protein functional requirements for two prions allow for chaperone-dependent prion selection.

    Science.gov (United States)

    Harris, Julia M; Nguyen, Phil P; Patel, Milan J; Sporn, Zachary A; Hines, Justin K

    2014-07-01

    Yeast prions are heritable amyloid aggregates of functional yeast proteins; their propagation to subsequent cell generations is dependent upon fragmentation of prion protein aggregates by molecular chaperone proteins. Mounting evidence indicates the J-protein Sis1 may act as an amyloid specificity factor, recognizing prion and other amyloid aggregates and enabling Ssa and Hsp104 to act in prion fragmentation. Chaperone interactions with prions, however, can be affected by variations in amyloid-core structure resulting in distinct prion variants or 'strains'. Our genetic analysis revealed that Sis1 domain requirements by distinct variants of [PSI+] are strongly dependent upon overall variant stability. Notably, multiple strong [PSI+] variants can be maintained by a minimal construct of Sis1 consisting of only the J-domain and glycine/phenylalanine-rich (G/F) region that was previously shown to be sufficient for cell viability and [RNQ+] prion propagation. In contrast, weak [PSI+] variants are lost under the same conditions but maintained by the expression of an Sis1 construct that lacks only the G/F region and cannot support [RNQ+] propagation, revealing mutually exclusive requirements for Sis1 function between these two prions. Prion loss is not due to [PSI+]-dependent toxicity or dependent upon a particular yeast genetic background. These observations necessitate that Sis1 must have at least two distinct functional roles that individual prions differentially require for propagation and which are localized to the glycine-rich domains of the Sis1. Based on these distinctions, Sis1 plasmid-shuffling in a [PSI+]/[RNQ+] strain permitted J-protein-dependent prion selection for either prion. We also found that, despite an initial report to the contrary, the human homolog of Sis1, Hdj1, is capable of [PSI+] prion propagation in place of Sis1. This conservation of function is also prion-variant dependent, indicating that only one of the two Sis1-prion functions may have

  19. An acoustic prion assay

    Directory of Open Access Journals (Sweden)

    Gordon Hayward

    2016-12-01

    Full Text Available An acoustic prion assay has been demonstrated for sheep brain samples. Only five false positives and no false negatives were observed in a test of 45 positive and 45 negative samples. The acoustic prion sensor was constructed using a thickness shear mode quartz resonator coated with a covalently bound recombinant prion protein. The characteristic indicator of a scrapie infected sheep brain sample was an observed shoulder in the frequency decrease in response to a sample.The response of the sensor aligns with a conformational shift in the surface protein and with the propagation mechanism of the disease. This alignment is evident in the response timing and shape, dependence on concentration, cross species behaviour and impact of blood plasma. This alignment is far from sufficient to prove the mechanism of the sensor but it does offer the possibility of a rapid and inexpensive additional tool to explore prion disease. Keywords: Prions, Thickness shear mode quartz sensor

  20. The contribution of different prion protein types and host polymorphisms to clinicopathological variations in Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Head, Mark W; Ironside, James W

    2012-07-01

    Creutzfeldt-Jakob disease is a fatal neurodegenerative disease that primarily affects the central nervous system. In this respect, it can be considered alongside the more frequently occurring neurodegenerative diseases, such as Alzheimer's disease. Creutzfeldt-Jakob disease is perhaps the paradigmatic protein misfolding disorder, so comparisons between the mechanisms involved in Creutzfeldt-Jakob disease and other neurodegenerative diseases associated with protein misfolding (such as the tauopathies and synucleinopathies) may also be informative. Like many of these diseases, Creutzfeldt-Jakob disease occurs sporadically or can, more rarely, be associated with mutations. However, Creutzfeldt-Jakob disease can also be acquired and is experimentally transmissible. These properties have had profound public health implications and made the disease of interest to virologists, in addition to those interested in protein misfolding disorders and neurodegeneration. The possible causes for the pronounced phenotypic variation among different forms of Creutzfeldt-Jakob disease are beginning to become understood, and these appear to depend in large measure on the genetics of the host (specifically the sequence of the prion protein gene, PRNP) and the epigenetic aspects of the agent (thought to be a misfolded and aggregated form of the PRNP gene product, termed a prion). This review will examine whether this model in its present form has sufficient complexity and subtlety to account for the clinicopathological variation evident in Creutzfeldt-Jakob disease and will outline the ways in which a more complete and informative molecular definition of human prions are currently being sought. Copyright © 2012 John Wiley & Sons, Ltd.

  1. Thermodynamic Stabilization of the Folded Domain of Prion Protein Inhibits Prion Infection in Vivo

    Directory of Open Access Journals (Sweden)

    Qingzhong Kong

    2013-07-01

    Full Text Available Prion diseases, or transmissible spongiform encephalopathies (TSEs, are associated with the conformational conversion of the cellular prion protein, PrPC, into a protease-resistant form, PrPSc. Here, we show that mutation-induced thermodynamic stabilization of the folded, α-helical domain of PrPC has a dramatic inhibitory effect on the conformational conversion of prion protein in vitro, as well as on the propagation of TSE disease in vivo. Transgenic mice expressing a human prion protein variant with increased thermodynamic stability were found to be much more resistant to infection with the TSE agent than those expressing wild-type human prion protein, in both the primary passage and three subsequent subpassages. These findings not only provide a line of evidence in support of the protein-only model of TSEs but also yield insight into the molecular nature of the PrPC→PrPSc conformational transition, and they suggest an approach to the treatment of prion diseases.

  2. Prions and animal transmissible spongiform encephalopathies

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    Juntes Polona

    2017-01-01

    Full Text Available Background. Transmissible spongiform encephalopathies (TSEs or prion diseases are a unique group of neurodegenerative diseases of animals and humans, which always have a fatal outcome and are transmissible among animals of the same or different species. Scope and Approach. The aim of this work is to review some recent data about animal TSEs, with the emphasis on their causative agents and zoonotic potential, and to discuss why the surveillance and control measures over animal TSEs should remain in force. Key Findings and Conclusions. We still have incomplete knowledge of prions and prion diseases. Scrapie has been present for a very long time and controlled with varied success. Bovine spongiform encephalopathy (BSE emerged unnoticed, and spread within a few years to epidemic proportions, entailing enormous economic consequences and public concerns. Currently, the classical BSE epidemic is under control, but atypical cases do, and probably will, persist in bovine populations. The Chronic Wasting Disease (CWD of the cervids has been spreading in North America and has recently been detected in Europe. Preventive measures for the control of classical BSE remain in force, including the feed ban and removal of specified risk materials. However, active BSE surveillance has considerably decreased. In the absence of such preventive and control measures, atypical BSE cases in healthy slaughtered bovines might persist in the human food chain, and BSE prions might resurface. Moreover, other prion strains might emerge and spread undetected if the appropriate preventive and surveillance measures were to cease, leaving behind inestimable consequences.

  3. The human homologue of unc-93 maps to chromosome 6q27 - characterisation and analysis in sporadic epithelial ovarian cancer

    DEFF Research Database (Denmark)

    Liu, Ying; Dodds, Phillippa; Emilion, Gracy

    2002-01-01

    In sporadic ovarian cancer, we have previously reported allele loss at D6S193 (62%) on chromosome 6q27, which suggested the presence of a putative tumour suppressor gene. Based on our data and that from another group, the minimal region of allele loss was between D6S264 and D6S149 (7.4 cM). To id...

  4. Biosafety of Prions.

    Science.gov (United States)

    Bistaffa, Edoardo; Rossi, Martina; De Luca, Chiara M G; Moda, Fabio

    2017-01-01

    Prions are the infectious agents that cause devastating and untreatable disorders known as Transmissible Spongiform Encephalopathies (TSEs). The pathologic events and the infectious nature of these transmissible agents are not completely understood yet. Due to the difficulties in inactivating prions, working with them requires specific recommendations and precautions. Moreover, with the advent of innovative technologies, such as the Protein Misfolding Cyclic Amplification (PMCA) and the Real Time Quaking-Induced Conversion (RT-QuIC), prions could be amplified in vitro and the infectious features of the amplified products need to be carefully assessed. © 2017 Elsevier Inc. All rights reserved.

  5. Amyloid cores in prion domains: Key regulators for prion conformational conversion.

    Science.gov (United States)

    Fernández, María Rosario; Batlle, Cristina; Gil-García, Marcos; Ventura, Salvador

    2017-01-02

    Despite the significant efforts devoted to decipher the particular protein features that encode for a prion or prion-like behavior, they are still poorly understood. The well-characterized yeast prions constitute an ideal model system to address this question, because, in these proteins, the prion activity can be univocally assigned to a specific region of their sequence, known as the prion forming domain (PFD). These PFDs are intrinsically disordered, relatively long and, in many cases, of low complexity, being enriched in glutamine/asparagine residues. Computational analyses have identified a significant number of proteins having similar domains in the human proteome. The compositional bias of these regions plays an important role in the transition of the prions to the amyloid state. However, it is difficult to explain how composition alone can account for the formation of specific contacts that position correctly PFDs and provide the enthalpic force to compensate for the large entropic cost of immobilizing these domains in the initial assemblies. We have hypothesized that short, sequence-specific, amyloid cores embedded in PFDs can perform these functions and, accordingly, act as preferential nucleation centers in both spontaneous and seeded aggregation. We have shown that the implementation of this concept in a prediction algorithm allows to score the prion propensities of putative PFDs with high accuracy. Recently, we have provided experimental evidence for the existence of such amyloid cores in the PFDs of Sup35, Ure2, Swi1, and Mot3 yeast prions. The fibrils formed by these short stretches may recognize and promote the aggregation of the complete proteins inside cells, being thus a promising tool for targeted protein inactivation.

  6. Gene knockout of tau expression does not contribute to the pathogenesis of prion disease.

    Science.gov (United States)

    Lawson, Victoria A; Klemm, Helen M; Welton, Jeremy M; Masters, Colin L; Crouch, Peter; Cappai, Roberto; Ciccotosto, Giuseppe D

    2011-11-01

    Prion diseases or transmissible spongiform encephalopathies are a group of fatal and transmissible disorders affecting the central nervous system of humans and animals. The principal agent of prion disease transmission and pathogenesis is proposed to be an abnormal protease-resistant isoform of the normal cellular prion protein. The microtubule-associated protein tau is elevated in patients with Creutzfeldt-Jakob disease. To determine whether tau expression contributes to prion disease pathogenesis, tau knockout and control wild-type mice were infected with the M1000 strain of mouse-adapted human prions. Immunohistochemical analysis for total tau expression in prion-infected wild-type mice indicated tau aggregation in the cytoplasm of a subpopulation of neurons in regions associated with spongiform change. Western immunoblot analysis of brain homogenates revealed a decrease in total tau immunoreactivity and epitope-specific changes in tau phosphorylation. No significant difference in incubation period or other disease features were observed between tau knockout and wild-type mice with clinical prion disease. These results demonstrate that, in this model of prion disease, tau does not contribute to the pathogenesis of prion disease and that changes in the tau protein profile observed in mice with clinical prion disease occurs as a consequence of the prion-induced pathogenesis.

  7. Inactivation of prion infectivity by ionizing rays

    Energy Technology Data Exchange (ETDEWEB)

    Gominet, M. [Ionisos, ZI les Chatinieres, F01120 Dagneux (France); Vadrot, C.; Austruy, G. [Paris V University, Central Pharmacy of Hospitals, 4 avenue de l' Observatoire, F-75006, Paris (France); Darbord, J.C. [Paris V University, Central Pharmacy of Hospitals, 4 avenue de l' Observatoire, F-75006, Paris (France)], E-mail: darbord@pharmacie.univ-paris5.fr

    2007-11-15

    Inactivation of prion deposits on medical devices or prion contamination in pharmaceutical raw materials is considered as impossible by using gamma irradiation. Early, the guideline WHO/CDS/CSR/APH/2000 has described irradiation as an ineffective process. But, in 2003, S. Miekka et al. noted radiation inactivation of prions in a particular application to purify human albumin, shown by the physical denaturation of the infectious protein (PrP). The aim of our study was to determine the inactivation of prions with a scrapie model (strain C506M3) by irradiating standardised preparations. Results: Gamma irradiation was partially effective, showing a 4-5 log reduction on exposure to 50 kGy. A characteristic effect-dose curve was not observed (25, 50 and 100 kGy), only an increase in the incubation period of the murine disease (229 days with 25 kGy to 290 days with 100 kGy) compared with 170 days without irradiation. Since the inactivation was not a total one, the observed effect is significant. It is proposed that further work be undertaken with the model to investigate the application of gamma radiation known levels of prion contamination.

  8. Inactivation of prion infectivity by ionizing rays

    International Nuclear Information System (INIS)

    Gominet, M.; Vadrot, C.; Austruy, G.; Darbord, J.C.

    2007-01-01

    Inactivation of prion deposits on medical devices or prion contamination in pharmaceutical raw materials is considered as impossible by using gamma irradiation. Early, the guideline WHO/CDS/CSR/APH/2000 has described irradiation as an ineffective process. But, in 2003, S. Miekka et al. noted radiation inactivation of prions in a particular application to purify human albumin, shown by the physical denaturation of the infectious protein (PrP). The aim of our study was to determine the inactivation of prions with a scrapie model (strain C506M3) by irradiating standardised preparations. Results: Gamma irradiation was partially effective, showing a 4-5 log reduction on exposure to 50 kGy. A characteristic effect-dose curve was not observed (25, 50 and 100 kGy), only an increase in the incubation period of the murine disease (229 days with 25 kGy to 290 days with 100 kGy) compared with 170 days without irradiation. Since the inactivation was not a total one, the observed effect is significant. It is proposed that further work be undertaken with the model to investigate the application of gamma radiation known levels of prion contamination

  9. MicroRNA (miRNA Signaling in the Human CNS in Sporadic Alzheimer’s Disease (AD-Novel and Unique Pathological Features

    Directory of Open Access Journals (Sweden)

    Yuhai Zhao

    2015-12-01

    Full Text Available Of the approximately ~2.65 × 103 mature microRNAs (miRNAs so far identified in Homo sapiens, only a surprisingly small but select subset—about 35–40—are highly abundant in the human central nervous system (CNS. This fact alone underscores the extremely high selection pressure for the human CNS to utilize only specific ribonucleotide sequences contained within these single-stranded non-coding RNAs (ncRNAs for productive miRNA–mRNA interactions and the down-regulation of gene expression. In this article we will: (i consolidate some of our still evolving ideas concerning the role of miRNAs in the CNS in normal aging and in health, and in sporadic Alzheimer’s disease (AD and related forms of chronic neurodegeneration; and (ii highlight certain aspects of the most current work in this research field, with particular emphasis on the findings from our lab of a small pathogenic family of six inducible, pro-inflammatory, NF-κB-regulated miRNAs including miRNA-7, miRNA-9, miRNA-34a, miRNA-125b, miRNA-146a and miRNA-155. This group of six CNS-abundant miRNAs significantly up-regulated in sporadic AD are emerging as what appear to be key mechanistic contributors to the sporadic AD process and can explain much of the neuropathology of this common, age-related inflammatory neurodegeneration of the human CNS.

  10. MicroRNA (miRNA) Signaling in the Human CNS in Sporadic Alzheimer’s Disease (AD)-Novel and Unique Pathological Features

    Science.gov (United States)

    Zhao, Yuhai; Pogue, Aileen I.; Lukiw, Walter J.

    2015-01-01

    Of the approximately ~2.65 × 103 mature microRNAs (miRNAs) so far identified in Homo sapiens, only a surprisingly small but select subset—about 35–40—are highly abundant in the human central nervous system (CNS). This fact alone underscores the extremely high selection pressure for the human CNS to utilize only specific ribonucleotide sequences contained within these single-stranded non-coding RNAs (ncRNAs) for productive miRNA–mRNA interactions and the down-regulation of gene expression. In this article we will: (i) consolidate some of our still evolving ideas concerning the role of miRNAs in the CNS in normal aging and in health, and in sporadic Alzheimer’s disease (AD) and related forms of chronic neurodegeneration; and (ii) highlight certain aspects of the most current work in this research field, with particular emphasis on the findings from our lab of a small pathogenic family of six inducible, pro-inflammatory, NF-κB-regulated miRNAs including miRNA-7, miRNA-9, miRNA-34a, miRNA-125b, miRNA-146a and miRNA-155. This group of six CNS-abundant miRNAs significantly up-regulated in sporadic AD are emerging as what appear to be key mechanistic contributors to the sporadic AD process and can explain much of the neuropathology of this common, age-related inflammatory neurodegeneration of the human CNS. PMID:26694372

  11. Validation of α-Synuclein as a CSF Biomarker for Sporadic Creutzfeldt-Jakob Disease.

    Science.gov (United States)

    Llorens, Franc; Kruse, Niels; Karch, André; Schmitz, Matthias; Zafar, Saima; Gotzmann, Nadine; Sun, Ting; Köchy, Silja; Knipper, Tobias; Cramm, Maria; Golanska, Ewa; Sikorska, Beata; Liberski, Pawel P; Sánchez-Valle, Raquel; Fischer, Andre; Mollenhauer, Brit; Zerr, Inga

    2018-03-01

    The analysis of cerebrospinal fluid (CSF) biomarkers gains importance in the differential diagnosis of prion diseases. However, no single diagnostic tool or combination of them can unequivocally confirm prion disease diagnosis. Electrochemiluminescence (ECL)-based immunoassays have demonstrated to achieve high diagnostic accuracy in a variety of sample types due to their high sensitivity and dynamic range. Quantification of CSF α-synuclein (a-syn) by an in-house ECL-based ELISA assay has been recently reported as an excellent approach for the diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD), the most prevalent form of human prion disease. In the present study, we validated a commercially available ECL-based a-syn ELISA platform as a diagnostic test for correct classification of sCJD cases. CSF a-syn was analysed in 203 sCJD cases with definite diagnosis and in 445 non-CJD cases. We investigated reproducibility and stability of CSF a-syn and made recommendations for its analysis in the sCJD diagnostic workup. A sensitivity of 98% and a specificity of 97% were achieved when using an optimal cut-off of 820 pg/mL a-syn. Moreover, we were able to show a negative correlation between a-syn levels and disease duration suggesting that CSF a-syn may be a good prognostic marker for sCJD patients. The present study validates the use of a-syn as a CSF biomarker of sCJD and establishes the clinical and pre-analytical parameters for its use in differential diagnosis in clinical routine. Additionally, the current test presents some advantages compared to other diagnostic approaches: it is fast, economic, requires minimal amount of CSF and a-syn levels are stable along disease progression.

  12. Pin1 and neurodegeneration: a new player for prion disorders?

    Directory of Open Access Journals (Sweden)

    Elisa Isopi

    2015-07-01

    Full Text Available Pin1 is a peptidyl-prolyl isomerase that catalyzes the cis/trans conversion of phosphorylated proteins at serine or threonine residues which precede a proline. The peptidyl-prolyl isomerization induces a conformational change of the proteins involved in cell signaling process. Pin1 dysregulation has been associated with some neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease and Huntington's disease. Proline-directed phosphorylation is a common regulator of these pathologies and a recent work showed that it is also involved in prion disorders. In fact, prion protein phosphorylation at the Ser-43-Pro motif induces prion protein conversion into a disease-associated form. Furthermore, phosphorylation at Ser-43-Pro has been observed to increase in the cerebral spinal fluid of sporadic Creutzfeldt-Jakob Disease patients. These findings provide new insights into the pathogenesis of prion disorders, suggesting Pin1 as a potential new player in the disease. In this paper, we review the mechanisms underlying Pin1 involvement in the aforementioned neurodegenerative pathologies focusing on the potential role of Pin1 in prion disorders.

  13. Ovine recombinant PrP as an inhibitor of ruminant prion propagation in vitro.

    Science.gov (United States)

    Workman, Rob G; Maddison, Ben C; Gough, Kevin C

    2017-07-04

    Prion diseases are fatal and incurable neurodegenerative diseases of humans and animals. Despite years of research, no therapeutic agents have been developed that can effectively manage or reverse disease progression. Recently it has been identified that recombinant prion proteins (rPrP) expressed in bacteria can act as inhibitors of prion replication within the in vitro prion replication system protein misfolding cyclic amplification (PMCA). Here, within PMCA reactions amplifying a range of ruminant prions including distinct Prnp genotypes/host species and distinct prion strains, recombinant ovine VRQ PrP displayed consistent inhibition of prion replication and produced IC50 values of 122 and 171 nM for ovine scrapie and bovine BSE replication, respectively. These findings illustrate the therapeutic potential of rPrPs with distinct TSE diseases.

  14. Scrapie susceptibility-linked polymorphisms modulate the in vitro conversion of sheep prion protein to protease-resistant forms

    NARCIS (Netherlands)

    Bossers, A.; Belt, P.B.G.M.; Raymond, G.J.; Caughey, B.; Vries, de R.; Smits, M.

    1997-01-01

    Prion diseases are natural transmissible neurodegenerative disorders in humans and animals. They are characterized by the accumulation of a protease-resistant scrapie-associated prion protein (PrPSc) of the host-encoded cellular prion protein (PrPC) mainly in the central nervous system.

  15. Generation of a human induced pluripotent stem cell line (CSC-42 from a patient with sporadic form of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Ekaterina Savchenko

    2018-03-01

    Full Text Available Skin fibroblasts were collected from a 44-year-old patient with sporadic case of Parkinson's disease (PD. The non-integrating Sendai virus vector encoding OCT3/4, SOX2, c-MYC and KLF4 was used to reprogram fibroblasts into induced pluripotent stem cells (iPSCs. Generated iPSCs had normal karyotypes, expressed common stem cell markers, and were capable of differentiating into all three germ layers. Generated line could be used for PD modeling to understand the mechanisms that influence the disorder.

  16. Heterozygous genotype at codon 129 correlates with prolonged disease course in Heidenhain variant sporadic CJD: case report.

    Science.gov (United States)

    Townley, Ryan A; Dawson, Elliot T; Drubach, Daniel A

    2018-02-01

    Sporadic Creutzfeldt-Jakob disease (sCJD) is a rapid and fatal neurodegenerative disease defined by misfolded prion proteins accumulating in the brain. A minority of cases initially present with posterior cortical atrophy (PCA) phenotype, also known as Heidenhain variant or visual variant CJD. This case provides further evidence of sCJD presenting as PCA. The case also provides evidence for early DWI changes and cortical atrophy over 30 months before neurologic decline and subsequent death. The prolonged disease course correlates with prion protein codon 129 heterozygosity and coexistence of multiple prion strains.

  17. Transmissible Spongiform Encephalopathies (Prion Diseases)

    Science.gov (United States)

    ... This research is aimed at determining how abnormal prion proteins lead to disease, at finding better tests ... This research is aimed at determining how abnormal prion proteins lead to disease, at finding better tests ...

  18. PrionHome: a database of prions and other sequences relevant to prion phenomena.

    Directory of Open Access Journals (Sweden)

    Djamel Harbi

    Full Text Available Prions are units of propagation of an altered state of a protein or proteins; prions can propagate from organism to organism, through cooption of other protein copies. Prions contain no necessary nucleic acids, and are important both as both pathogenic agents, and as a potential force in epigenetic phenomena. The original prions were derived from a misfolded form of the mammalian Prion Protein PrP. Infection by these prions causes neurodegenerative diseases. Other prions cause non-Mendelian inheritance in budding yeast, and sometimes act as diseases of yeast. We report the bioinformatic construction of the PrionHome, a database of >2000 prion-related sequences. The data was collated from various public and private resources and filtered for redundancy. The data was then processed according to a transparent classification system of prionogenic sequences (i.e., sequences that can make prions, prionoids (i.e., proteins that propagate like prions between individual cells, and other prion-related phenomena. There are eight PrionHome classifications for sequences. The first four classifications are derived from experimental observations: prionogenic sequences, prionoids, other prion-related phenomena, and prion interactors. The second four classifications are derived from sequence analysis: orthologs, paralogs, pseudogenes, and candidate-prionogenic sequences. Database entries list: supporting information for PrionHome classifications, prion-determinant areas (where relevant, and disordered and compositionally-biased regions. Also included are literature references for the PrionHome classifications, transcripts and genomic coordinates, and structural data (including comparative models made for the PrionHome from manually curated alignments. We provide database usage examples for both vertebrate and fungal prion contexts. Using the database data, we have performed a detailed analysis of the compositional biases in known budding-yeast prionogenic

  19. PrionHome: a database of prions and other sequences relevant to prion phenomena.

    Science.gov (United States)

    Harbi, Djamel; Parthiban, Marimuthu; Gendoo, Deena M A; Ehsani, Sepehr; Kumar, Manish; Schmitt-Ulms, Gerold; Sowdhamini, Ramanathan; Harrison, Paul M

    2012-01-01

    Prions are units of propagation of an altered state of a protein or proteins; prions can propagate from organism to organism, through cooption of other protein copies. Prions contain no necessary nucleic acids, and are important both as both pathogenic agents, and as a potential force in epigenetic phenomena. The original prions were derived from a misfolded form of the mammalian Prion Protein PrP. Infection by these prions causes neurodegenerative diseases. Other prions cause non-Mendelian inheritance in budding yeast, and sometimes act as diseases of yeast. We report the bioinformatic construction of the PrionHome, a database of >2000 prion-related sequences. The data was collated from various public and private resources and filtered for redundancy. The data was then processed according to a transparent classification system of prionogenic sequences (i.e., sequences that can make prions), prionoids (i.e., proteins that propagate like prions between individual cells), and other prion-related phenomena. There are eight PrionHome classifications for sequences. The first four classifications are derived from experimental observations: prionogenic sequences, prionoids, other prion-related phenomena, and prion interactors. The second four classifications are derived from sequence analysis: orthologs, paralogs, pseudogenes, and candidate-prionogenic sequences. Database entries list: supporting information for PrionHome classifications, prion-determinant areas (where relevant), and disordered and compositionally-biased regions. Also included are literature references for the PrionHome classifications, transcripts and genomic coordinates, and structural data (including comparative models made for the PrionHome from manually curated alignments). We provide database usage examples for both vertebrate and fungal prion contexts. Using the database data, we have performed a detailed analysis of the compositional biases in known budding-yeast prionogenic sequences, showing

  20. Persistence of pathogenic prion protein during simulated wastewater treatment processes

    Science.gov (United States)

    Hinckley, G.T.; Johnson, C.J.; Jacobson, K.H.; Bartholomay, C.; Mcmahon, K.D.; McKenzie, D.; Aiken, Judd M.; Pedersen, J.A.

    2008-01-01

    Transmissible spongiform encephalopathies (TSEs, prion diseases) are a class of fatal neurodegenerative diseases affecting a variety of mammalian species including humans. A misfolded form of the prion protein (PrP TSE) is the major, if not sole, component of the infectious agent. Prions are highly resistant to degradation and to many disinfection procedures suggesting that, if prions enter wastewater treatment systems through sewers and/or septic systems (e.g., from slaughterhouses, necropsy laboratories, rural meat processors, private game dressing) or through leachate from landfills that have received TSE-contaminated material, prions could survive conventional wastewater treatment Here, we report the results of experiments examining the partitioning and persistence of PrPTSE during simulated wastewater treatment processes including activated and mesophilic anaerobic sludge digestion. Incubation with activated sludge did not result in significant PrPTSE degradation. PrPTSE and prion infectivity partitioned strongly to activated sludge solids and are expected to enter biosolids treatment processes. A large fraction of PrPTSE survived simulated mesophilic anaerobic sludge digestion. The small reduction in recoverable PrPTSE after 20-d anaerobic sludge digestion appeared attributable to a combination of declining extractability with time and microbial degradation. Our results suggest that if prions were to enter municipal wastewater treatment systems, most would partition to activated sludge solids, survive mesophilic anaerobic digestion, and be present in treated biosolids. ?? 2008 American Chemical Society.

  1. The non-octarepeat copper binding site of the prion protein is a key regulator of prion conversion

    Science.gov (United States)

    Giachin, Gabriele; Mai, Phuong Thao; Tran, Thanh Hoa; Salzano, Giulia; Benetti, Federico; Migliorati, Valentina; Arcovito, Alessandro; Longa, Stefano Della; Mancini, Giordano; D'Angelo, Paola; Legname, Giuseppe

    2015-10-01

    The conversion of the prion protein (PrPC) into prions plays a key role in transmissible spongiform encephalopathies. Despite the importance for pathogenesis, the mechanism of prion formation has escaped detailed characterization due to the insoluble nature of prions. PrPC interacts with copper through octarepeat and non-octarepeat binding sites. Copper coordination to the non-octarepeat region has garnered interest due to the possibility that this interaction may impact prion conversion. We used X-ray absorption spectroscopy to study copper coordination at pH 5.5 and 7.0 in human PrPC constructs, either wild-type (WT) or carrying pathological mutations. We show that mutations and pH cause modifications of copper coordination in the non-octarepeat region. In the WT at pH 5.5, copper is anchored to His96 and His111, while at pH 7 it is coordinated by His111. Pathological point mutations alter the copper coordination at acidic conditions where the metal is anchored to His111. By using in vitro approaches, cell-based and computational techniques, we propose a model whereby PrPC coordinating copper with one His in the non-octarepeat region converts to prions at acidic condition. Thus, the non-octarepeat region may act as the long-sought-after prion switch, critical for disease onset and propagation.

  2. Introduction to Sporadic Groups

    Directory of Open Access Journals (Sweden)

    Luis J. Boya

    2011-01-01

    Full Text Available This is an introduction to finite simple groups, in particular sporadic groups, intended for physicists. After a short review of group theory, we enumerate the 1+1+16=18 families of finite simple groups, as an introduction to the sporadic groups. These are described next, in three levels of increasing complexity, plus the six isolated ''pariah'' groups. The (old five Mathieu groups make up the first, smallest order level. The seven groups related to the Leech lattice, including the three Conway groups, constitute the second level. The third and highest level contains the Monster group M, plus seven other related groups. Next a brief mention is made of the remaining six pariah groups, thus completing the 5+7+8+6=26 sporadic groups. The review ends up with a brief discussion of a few of physical applications of finite groups in physics, including a couple of recent examples which use sporadic groups.

  3. How do PrPSc Prions Spread between Host Species, and within Hosts?

    Directory of Open Access Journals (Sweden)

    Neil A. Mabbott

    2017-11-01

    Full Text Available Prion diseases are sub-acute neurodegenerative diseases that affect humans and some domestic and free-ranging animals. Infectious prion agents are considered to comprise solely of abnormally folded isoforms of the cellular prion protein known as PrPSc. Pathology during prion disease is restricted to the central nervous system where it causes extensive neurodegeneration and ultimately leads to the death of the host. The first half of this review provides a thorough account of our understanding of the various ways in which PrPSc prions may spread between individuals within a population, both horizontally and vertically. Many natural prion diseases are acquired peripherally, such as by oral exposure, lesions to skin or mucous membranes, and possibly also via the nasal cavity. Following peripheral exposure, some prions accumulate to high levels within the secondary lymphoid organs as they make their journey from the site of infection to the brain, a process termed neuroinvasion. The replication of PrPSc prions within secondary lymphoid organs is important for their efficient spread to the brain. The second half of this review describes the key tissues, cells and molecules which are involved in the propagation of PrPSc prions from peripheral sites of exposure (such as the lumen of the intestine to the brain. This section also considers how additional factors such as inflammation and aging might influence prion disease susceptibility.

  4. Incunabular Immunological Events in Prion Trafficking

    Science.gov (United States)

    Michel, Brady; Meyerett-Reid, Crystal; Johnson, Theodore; Ferguson, Adam; Wyckoff, Christy; Pulford, Bruce; Bender, Heather; Avery, Anne; Telling, Glenn; Dow, Steven; Zabel, Mark D.

    2012-01-01

    While prions probably interact with the innate immune system immediately following infection, little is known about this initial confrontation. Here we investigated incunabular events in lymphotropic and intranodal prion trafficking by following highly enriched, fluorescent prions from infection sites to draining lymph nodes. We detected biphasic lymphotropic transport of prions from the initial entry site upon peripheral prion inoculation. Prions arrived in draining lymph nodes cell autonomously within two hours of intraperitoneal administration. Monocytes and dendritic cells (DCs) required Complement for optimal prion delivery to lymph nodes hours later in a second wave of prion trafficking. B cells constituted the majority of prion-bearing cells in the mediastinal lymph node by six hours, indicating intranodal prion reception from resident DCs or subcapsulary sinus macrophages or directly from follicular conduits. These data reveal novel, cell autonomous prion lymphotropism, and a prominent role for B cells in intranodal prion movement. PMID:22679554

  5. Current and future molecular diagnostics for prion diseases.

    Science.gov (United States)

    Lehto, Marty T; Peery, Harry E; Cashman, Neil R

    2006-07-01

    It is now widely held that the infectious agents underlying the transmissible spongiform encephalopathies are prions, which are primarily composed of a misfolded, protease-resistant isoform of the host prion protein. Untreatable prion disorders include some human diseases, such as Creutzfeldt-Jakob disease, and diseases of economically important animals, such as bovine spongiform encephalopathy (cattle) and chronic wasting disease (deer and elk). Detection and diagnosis of prion disease (and presymptomatic incubation) is contingent upon developing novel assays, which exploit properties uniquely possessed by this misfolded protein complex, rather than targeting an agent-specific nucleic acid. This review highlights some of the conventional and disruptive technologies developed to respond to this challenge.

  6. Repetitive immunization enhances the susceptibility of mice to peripherally administered prions.

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    Juliane Bremer

    Full Text Available 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.

  7. Pontine hyperperfusion in sporadic hyperekplexia.

    Science.gov (United States)

    Vetrugno, Roberto; Mascalchi, Mario; Vella, Alessandra; Della Nave, Riccardo; Guerrini, Laura; Vattimo, Angelo; del Giudice, Emanuele Miraglia; Plazzi, Giuseppe; D'Angelo, Roberto; Greco, Giovanni; Montagna, Pasquale

    2007-09-01

    To explore with neuroimaging techniques the anatomical and functional correlates of sporadic hyperekplexia. Two elderly women with sporadic hyperekplexia underwent neurophysiological assessment, MRI of the brain and proton magnetic resonance spectroscopy (1H-MRS) of the brainstem and frontal lobes. Regional cerebral blood flow was investigated with single photon emission tomography (SPECT) during evoked startles and at rest. Both patients showed excessively large and non-habituating startle responses. In both patients, MRI showed impingement of the brainstem by the vertebrobasilar artery, lack of frontal or brainstem abnormalities on 1H-MRS and hyperperfusion in the dorsal pons and cingulate cortex, and superior frontal gyrus at SPECT during evoked startles. In our patients with hyperekplexia, the vertebrobasilar arteries were found to impinge on the brainstem. Neurophysiological findings and neurofunctional imaging of evoked startles indicated a pontine origin of the movement disorder modulated by activation in cortical, especially frontal, areas. The neurofunctional correlates of evoked startles in human sporadic hyperekplexia are similar to those observed for the startle circuit in animals.

  8. Serum uric acid and lipid profiles in sporadic Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Chen, Shuai; He, Shuang; Shang, Jun-Kui; Ma, Ming-Ming; Xu, Chang-Shui; Shi, Xiao-Hong; Zhang, Jie-Wen

    2016-02-01

    Creutzfeldt-Jakob disease (CJD) is a rare, rapidly progressive, and fatal neurodegenerative disease affecting the central nervous system. Brain lipid homeostasis and oxidative stress seem to play an important role in the disease pathogenesis. But little was known whether serum lipids and uric acid (a natural antioxidant) levels changed in patients with prion disease. Here we retrospectively reviewed and compared the serum lipids and uric acid levels of 19 probable sporadic CJD patients and 26 healthy control subjects. We found that the serum uric acid levels in sporadic CJD patients were significantly lower than that in controls (P=0.01). Serum triglycerides, cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and apolipoprotein A1 (ApoA1) were similar in sporadic CJD patients and controls. However, LDL/HDL ratio was lower in sporadic CJD patients (P=0.003). The low serum uric acid and LDL/HDL ratio levels in sporadic CJD indicate that dysfunction in the lipid homeostasis and oxidative stress is associated with sporadic prion disease. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  9. Diffusion MR imaging in sporadic Creutzfeldt-Jakob disease

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    Burcak Cakir Pekoz

    2014-08-01

    Full Text Available Creutzfeldt-Jakob disease (CJD is a rare dementing disease and is thought to caused by a prion. It is characterized by rapidly progressive dementia, ataxia, myoclonus, akinetic mutism and eventual death. Brain biopsy or autopsy is required for a definitive diagnosis of CJD. Diffusion-weighted imaging became an important tool for early diagnosis of CJD because of the high sensitivity. We present 59-year-old female patient diagnosed as sporadic CJD with typical MR imagings. [Cukurova Med J 2014; 39(4.000: 880-883

  10. Pros and cons of a prion-like pathogenesis in Parkinson's disease

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    Brotchie Jonathan M

    2011-06-01

    Full Text Available Abstract Background Parkinson's disease (PD is a slowly progressive neurodegenerative disorder which affects widespread areas of the brainstem, basal ganglia and cerebral cortex. A number of proteins are known to accumulate in parkinsonian brains including ubiquitin and α-synuclein. Prion diseases are sporadic, genetic or infectious disorders with various clinical and histopathological features caused by prion proteins as infectious proteinaceous particles transmitting a misfolded protein configuration through brain tissue. The most important form is Creutzfeldt-Jakob disease which is associated with a self-propagating pathological precursor form of the prion protein that is physiologically widely distributed in the central nervous system. Discussion It has recently been found that α-synuclein may behave similarly to the prion precursor and propagate between cells. The post-mortem proof of α-synuclein containing Lewy bodies in embryonic dopamine cells transplants in PD patient suggests that the misfolded protein might be transmitted from the diseased host to donor neurons reminiscent of prion behavior. The involvement of the basal ganglia and brainstem in the degenerative process are other congruencies between Parkinson's and Creutzfeldt-Jakob disease. However, a number of issues advise caution before categorizing Parkinson's disease as a prion disorder, because clinical appearance, brain imaging, cerebrospinal fluid and neuropathological findings exhibit fundamental differences between both disease entities. Most of all, infectiousness, a crucial hallmark of prion diseases, has never been observed in PD so far. Moreover, the cellular propagation of the prion protein has not been clearly defined and it is, therefore, difficult to assess the molecular similarities between the two disease entities. Summary At the current state of knowledge, the molecular pathways of transmissible pathogenic proteins are not yet fully understood. Their exact

  11. Prion Protein and Aging

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    Lisa eGasperini

    2014-08-01

    Full Text Available The cellular prion protein (PrPC has been widely investigated ever since its conformational isoform, the prion (or PrPSc, was identified as the etiological agent of prion disorders. The high homology shared by the PrPC-encoding gene among mammals, its high turnover rate and expression in every tissue strongly suggest that PrPC may possess key physiological functions. Therefore, defining PrPC roles, properties and fate in the physiology of mammalian cells would be fundamental to understand its pathological involvement in prion diseases. Since the incidence of these neurodegenerative disorders is enhanced in aging, understanding PrPC functions in this life phase may be of crucial importance. Indeed, a large body of evidence suggests that PrPC plays a neuroprotective and antioxidant role. Moreover, it has been suggested that PrPC is involved in Alzheimer disease, another neurodegenerative pathology that develops predominantly in the aging population. In prion diseases, PrPC function is likely lost upon protein aggregation occurring in the course of the disease. Additionally, the aging process may alter PrPC biochemical properties, thus influencing its propensity to convert into PrPSc. Both phenomena may contribute to the disease development and progression. In Alzheimer disease, PrPC has a controversial role because its presence seems to mediate β-amyloid toxicity, while its down-regulation correlates with neuronal death. The role of PrPC in aging has been investigated from different perspectives, often leading to contrasting results. The putative protein functions in aging have been studied in relation to memory, behavior and myelin maintenance. In aging mice, PrPC changes in subcellular localization and post-translational modifications have been explored in an attempt to relate them to different protein roles and propensity to convert into PrPSc. Here we provide an overview of the most relevant studies attempting to delineate PrPC functions and

  12. NMR experiments for resonance assignments of 13C, 15N doubly-labeled flexible polypeptides: Application to the human prion protein hPrP(23-230)

    International Nuclear Information System (INIS)

    Liu Aizhuo; Riek, Roland; Wider, Gerhard; Schroetter, Christine von; Zahn, Ralph; Wuethrich, Kurt

    2000-01-01

    A combination of three heteronuclear three-dimensional NMR experiments tailored for sequential resonance assignments in uniformly 15 N, 13 C-labeled flexible polypeptide chains is described. The 3D (H)N(CO-TOCSY)NH, 3D (H)CA(CO-TOCSY)NH and 3D (H)CBCA(CO-TOCSY)NH schemes make use of the favorable 15 N chemical shift dispersion in unfolded polypeptides, exploit the slow transverse 15 N relaxation rates of unfolded polypeptides in high resolution constant-time [ 1 H, 15 N]-correlation experiments, and use carbonyl carbon homonuclear isotropic mixing to transfer magnetization sequentially along the amino acid sequence. Practical applications are demonstrated with the 100-residue flexible tail of the recombinant human prion protein, making use of spectral resolution up to 0.6 Hz in the 15 N dimension, simultaneous correlation with the two adjacent amino acid residues to overcome problems associated with spectral overlap, and the potential of the presently described experiments to establish nearest-neighbor correlations across proline residues in the amino acid sequence

  13. Effects of a naturally occurring amino acid substitution in bovine PrP: a model for inherited prion disease in a natural host species

    Science.gov (United States)

    The most common hereditary prion disease is human Creutzfeldt-Jakob disease (CJD) associated with a mutation in the prion gene (PRNP) resulting in a glutamic acid to lysine substitution at position 200 (E200K) in the prion protein. Models of E200K CJD in transgenic mice have proven interesting but h...

  14. Genes contributing to prion pathogenesis

    DEFF Research Database (Denmark)

    Tamgüney, Gültekin; Giles, Kurt; Glidden, David V

    2008-01-01

    incubation times, indicating that the conversion reaction may be influenced by other gene products. To identify genes that contribute to prion pathogenesis, we analysed incubation times of prions in mice in which the gene product was inactivated, knocked out or overexpressed. We tested 20 candidate genes...... show that many genes previously implicated in prion replication have no discernible effect on the pathogenesis of prion disease. While most genes tested did not significantly affect survival times, ablation of the amyloid beta (A4) precursor protein (App) or interleukin-1 receptor, type I (Il1r1...

  15. Cholesterol Balance in Prion Diseases and Alzheimer’s Disease

    Science.gov (United States)

    Hannaoui, Samia; Shim, Su Yeon; Cheng, Yo Ching; Corda, Erica; Gilch, Sabine

    2014-01-01

    Prion diseases are transmissible and fatal neurodegenerative disorders of humans and animals. They are characterized by the accumulation of PrPSc, an aberrantly folded isoform of the cellular prion protein PrPC, in the brains of affected individuals. PrPC is a cell surface glycoprotein attached to the outer leaflet of the plasma membrane by a glycosyl-phosphatidyl-inositol (GPI) anchor. Specifically, it is associated with lipid rafts, membrane microdomains enriched in cholesterol and sphinoglipids. It has been established that inhibition of endogenous cholesterol synthesis disturbs lipid raft association of PrPC and prevents PrPSc accumulation in neuronal cells. Additionally, prion conversion is reduced upon interference with cellular cholesterol uptake, endosomal export, or complexation at the plasma membrane. Altogether, these results demonstrate on the one hand the importance of cholesterol for prion propagation. On the other hand, growing evidence suggests that prion infection modulates neuronal cholesterol metabolism. Similar results were reported in Alzheimer’s disease (AD): whereas amyloid β peptide formation is influenced by cellular cholesterol, levels of cholesterol in the brains of affected individuals increase during the clinical course of the disease. In this review, we summarize commonalities of alterations in cholesterol homeostasis and discuss consequences for neuronal function and therapy of prion diseases and AD. PMID:25419621

  16. Cholesterol Balance in Prion Diseases and Alzheimer’s Disease

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    Samia Hannaoui

    2014-11-01

    Full Text Available Prion diseases are transmissible and fatal neurodegenerative disorders of humans and animals. They are characterized by the accumulation of PrPSc, an aberrantly folded isoform of the cellular prion protein PrPC, in the brains of affected individuals. PrPC is a cell surface glycoprotein attached to the outer leaflet of the plasma membrane by a glycosyl-phosphatidyl-inositol (GPI anchor. Specifically, it is associated with lipid rafts, membrane microdomains enriched in cholesterol and sphinoglipids. It has been established that inhibition of endogenous cholesterol synthesis disturbs lipid raft association of PrPC and prevents PrPSc accumulation in neuronal cells. Additionally, prion conversion is reduced upon interference with cellular cholesterol uptake, endosomal export, or complexation at the plasma membrane. Altogether, these results demonstrate on the one hand the importance of cholesterol for prion propagation. On the other hand, growing evidence suggests that prion infection modulates neuronal cholesterol metabolism. Similar results were reported in Alzheimer’s disease (AD: whereas amyloid β peptide formation is influenced by cellular cholesterol, levels of cholesterol in the brains of affected individuals increase during the clinical course of the disease. In this review, we summarize commonalities of alterations in cholesterol homeostasis and discuss consequences for neuronal function and therapy of prion diseases and AD.

  17. Hsp40 function in yeast prion propagation: Amyloid diversity necessitates chaperone functional complexity.

    Science.gov (United States)

    Sporn, Zachary A; Hines, Justin K

    2015-01-01

    Yeast prions are heritable protein-based elements, most of which are formed of amyloid aggregates that rely on the action of molecular chaperones for transmission to progeny. Prions can form distinct amyloid structures, known as 'strains' in mammalian systems, that dictate both pathological progression and cross-species infection barriers. In yeast these same amyloid structural polymorphisms, called 'variants', dictate the intensity of prion-associated phenotypes and stability in mitosis. We recently reported that [PSI(+)] prion variants differ in the fundamental domain requirements for one chaperone, the Hsp40/J-protein Sis1, which are mutually exclusive between 2 different yeast prions, demonstrating a functional plurality for Sis1. Here we extend that analysis to incorporate additional data that collectively support the hypothesis that Sis1 has multiple functional roles that can be accomplished by distinct sets of domains. These functions are differentially required by distinct prions and prion variants. We also present new data regarding Hsp104-mediated prion elimination and show that some Sis1 functions, but not all, are conserved in the human homolog Hdj1/DNAJB1. Importantly, of the 10 amyloid-based prions indentified to date in Saccharomyces cerevisiae, the chaperone requirements of only 4 are known, leaving a great diversity of amyloid structures, and likely modes of amyloid-chaperone interaction, largely unexplored.

  18. Red-backed vole brain promotes highly efficient in vitro amplification of abnormal prion protein from macaque and human brains infected with variant Creutzfeldt-Jakob disease agent.

    Science.gov (United States)

    Nemecek, Julie; Nag, Nabanita; Carlson, Christina M.; Schneider, Jay R.; Heisey, Dennis M.; Johnson, Christopher J.; Asher, David M.; Gregori, Luisa

    2013-01-01

    Rapid antemortem tests to detect individuals with transmissible spongiform encephalopathies (TSE) would contribute to public health. We investigated a technique known as protein misfolding cyclic amplification (PMCA) to amplify abnormal prion protein (PrPTSE) from highly diluted variant Creutzfeldt-Jakob disease (vCJD)-infected human and macaque brain homogenates, seeking to improve the rapid detection of PrPTSE in tissues and blood. Macaque vCJD PrPTSE did not amplify using normal macaque brain homogenate as substrate (intraspecies PMCA). Next, we tested interspecies PMCA with normal brain homogenate of the southern red-backed vole (RBV), a close relative of the bank vole, seeded with macaque vCJD PrPTSE. The RBV has a natural polymorphism at residue 170 of the PrP-encoding gene (N/N, S/S, and S/N). We investigated the effect of this polymorphism on amplification of human and macaque vCJD PrPTSE. Meadow vole brain (170N/N PrP genotype) was also included in the panel of substrates tested. Both humans and macaques have the same 170S/S PrP genotype. Macaque PrPTSE was best amplified with RBV 170S/S brain, although 170N/N and 170S/N were also competent substrates, while meadow vole brain was a poor substrate. In contrast, human PrPTSE demonstrated a striking narrow selectivity for PMCA substrate and was successfully amplified only with RBV 170S/S brain. These observations suggest that macaque PrPTSE was more permissive than human PrPTSE in selecting the competent RBV substrate. RBV 170S/S brain was used to assess the sensitivity of PMCA with PrPTSE from brains of humans and macaques with vCJD. PrPTSE signals were reproducibly detected by Western blot in dilutions through 10-12 of vCJD-infected 10% brain homogenates. This is the first report showing PrPTSE from vCJD-infected human and macaque brains efficiently amplified with RBV brain as the substrate. Based on our estimates, PMCA showed a sensitivity that might be sufficient to detect PrPTSE in v

  19. Red-backed vole brain promotes highly efficient in vitro amplification of abnormal prion protein from macaque and human brains infected with variant Creutzfeldt-Jakob disease agent.

    Directory of Open Access Journals (Sweden)

    Julie Nemecek

    Full Text Available Rapid antemortem tests to detect individuals with transmissible spongiform encephalopathies (TSE would contribute to public health. We investigated a technique known as protein misfolding cyclic amplification (PMCA to amplify abnormal prion protein (PrP(TSE from highly diluted variant Creutzfeldt-Jakob disease (vCJD-infected human and macaque brain homogenates, seeking to improve the rapid detection of PrP(TSE in tissues and blood. Macaque vCJD PrP(TSE did not amplify using normal macaque brain homogenate as substrate (intraspecies PMCA. Next, we tested interspecies PMCA with normal brain homogenate of the southern red-backed vole (RBV, a close relative of the bank vole, seeded with macaque vCJD PrP(TSE. The RBV has a natural polymorphism at residue 170 of the PrP-encoding gene (N/N, S/S, and S/N. We investigated the effect of this polymorphism on amplification of human and macaque vCJD PrP(TSE. Meadow vole brain (170N/N PrP genotype was also included in the panel of substrates tested. Both humans and macaques have the same 170S/S PrP genotype. Macaque PrP(TSE was best amplified with RBV 170S/S brain, although 170N/N and 170S/N were also competent substrates, while meadow vole brain was a poor substrate. In contrast, human PrP(TSE demonstrated a striking narrow selectivity for PMCA substrate and was successfully amplified only with RBV 170S/S brain. These observations suggest that macaque PrP(TSE was more permissive than human PrP(TSE in selecting the competent RBV substrate. RBV 170S/S brain was used to assess the sensitivity of PMCA with PrP(TSE from brains of humans and macaques with vCJD. PrP(TSE signals were reproducibly detected by Western blot in dilutions through 10⁻¹² of vCJD-infected 10% brain homogenates. This is the first report showing PrP(TSE from vCJD-infected human and macaque brains efficiently amplified with RBV brain as the substrate. Based on our estimates, PMCA showed a sensitivity that might be sufficient to detect Pr

  20. MM2-Thalamic Creutzfeldt-Jacob Disease: Neuropathological, Biochemical and Transmission Studies Identify a Distinctive Prion Strain

    NARCIS (Netherlands)

    Moda, F.; Suardi, S.; Fede, Di G.; Indaco, A.; Limido, L.; Vimercati, C.; Ruggerone, M.; Campagnani, I.; Langeveld, J.P.M.; Terruzzi, A.; Brambilla, A.; Zerbi, P.; Fociani, P.; Bishop, T.; Will, G.W.; Manson, J.C.; Giaccone, G.; Tagliavini, F.

    2012-01-01

    In CreutzfeldtJakob disease (CJD), molecular typing based on the size of the protease resistant core of the disease-associated prion protein (PrPSc) and the M/V polymorphism at codon 129 of the PRNP gene correlates with the clinico-pathologic subtypes. Approximately 95% of the sporadic 129MM CJD

  1. High prevalence of a fungal prion

    NARCIS (Netherlands)

    Debets, A.J.M.; Dalstra, H.J.P.; Slakhorst, S.M.; Koopmanschap-Memelink, A.B.; Hoekstra, R.F.; Saupe, S.J.

    2012-01-01

    Prions are infectious proteins that cause fatal diseases in mammals. Prions have also been found in fungi, but studies on their role in nature are scarce. The proposed biological function of fungal prions is debated and varies from detrimental to benign or even beneficial. [Het-s] is a prion of the

  2. Enhancer of the rudimentary gene homologue (ERH expression pattern in sporadic human breast cancer and normal breast tissue

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    Knüchel Ruth

    2008-05-01

    Full Text Available Abstract Background The human gene ERH (Enhancer of the Rudimentary gene Homologue has previously been identified by in silico analysis of four million ESTs as a gene differentially expressed in breast cancer. The biological function of ERH protein has not been fully elucidated, however functions in cell cycle progression, pyrimidine metabolism a possible interaction with p21(Cip1/Waf1 via the Ciz1 zinc finger protein have been suggested. The aim of the present study was a systematic characterization of ERH expression in human breast cancer in order to evaluate possible clinical applications of this molecule. Methods The expression pattern of ERH was analyzed using multiple tissue northern blots (MTN on a panel of 16 normal human tissues and two sets of malignant/normal breast and ovarian tissue samples. ERH expression was further analyzed in breast cancer and normal breast tissues and in tumorigenic as well as non-tumorigenic breast cancer cell lines, using quantitative RT-PCR and non-radioisotopic in situ hybridization (ISH. Results Among normal human tissues, ERH expression was most abundant in testis, heart, ovary, prostate, and liver. In the two MTN sets of malignant/normal breast and ovarian tissue,ERH was clearly more abundantly expressed in all tumours than in normal tissue samples. Quantitative RT-PCR analyses showed that ERH expression was significantly more abundant in tumorigenic than in non-tumorigenic breast cancer cell lines (4.5-fold; p = 0.05, two-tailed Mann-Whitney U-test; the same trend was noted in a set of 25 primary invasive breast cancers and 16 normal breast tissue samples (2.5-fold; p = 0.1. These findings were further confirmed by non-radioisotopic ISH in human breast cancer and normal breast tissue. Conclusion ERH expression is clearly up-regulated in malignant as compared with benign breast cells both in primary human breast cancer and in cell models of breast cancer. Since similar results were obtained for ovarian

  3. Prion protein and scrapie susceptibility

    NARCIS (Netherlands)

    Smits, M.A.; Bossers, A.; Schreuder, B.E.C.

    1997-01-01

    This article presents briefly current views on the role of prion protein (PrP) in Transmissible Spongiform Encephalopathies or prion diseases and the effect of PrP polymoryhisms on the susceptibility to these diseases, with special emphasis on sheep scrapie. The PrP genotype of sheep apears to be a

  4. Source attribution of human campylobacteriosis using a meta-analysis of case-control studies of sporadic infections

    DEFF Research Database (Denmark)

    Coutinho Calado Domingues, Ana Rita; Pires, Sara Monteiro; Hisham Beshara Halasa, Tariq

    2012-01-01

    Campylobacter spp. is a widespread and important cause of human illness worldwide. Disease is frequently associated with foodborne transmission, but other routes of exposure, such as direct contact with live animals and person-to-person transmission, are also recognized. Identifying the most impo...

  5. The many shades of prion strain adaptation.

    Science.gov (United States)

    Baskakov, Ilia V

    2014-01-01

    In several recent studies transmissible prion disease was induced in animals by inoculation with recombinant prion protein amyloid fibrils produced in vitro. Serial transmission of amyloid fibrils gave rise to a new class of prion strains of synthetic origin. Gradual transformation of disease phenotypes and PrP(Sc) properties was observed during serial transmission of synthetic prions, a process that resembled the phenomenon of prion strain adaptation. The current article discusses the remarkable parallels between phenomena of prion strain adaptation that accompanies cross-species transmission and the evolution of synthetic prions occurring within the same host. Two alternative mechanisms underlying prion strain adaptation and synthetic strain evolution are discussed. The current article highlights the complexity of the prion transmission barrier and strain adaptation and proposes that the phenomenon of prion adaptation is more common than previously thought.

  6. The human homologue of unc-93 maps to chromosome 6q27 – characterisation and analysis in sporadic epithelial ovarian cancer

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    Charnock F Mark L

    2002-10-01

    Full Text Available Abstract Background In sporadic ovarian cancer, we have previously reported allele loss at D6S193 (62% on chromosome 6q27, which suggested the presence of a putative tumour suppressor gene. Based on our data and that from another group, the minimal region of allele loss was between D6S264 and D6S149 (7.4 cM. To identify the putative tumour suppressor gene, we established a physical map initially with YACs and subsequently with PACs/BACs from D6S264 to D6S149. To accelerate the identification of genes, we sequenced the entire contig of approximately 1.1 Mb. Seven genes were identified within the region of allele loss between D6S264 and D6S149. Results The human homologue of unc-93 (UNC93A in C. elegans was identified to be within the interval of allele loss centromeric to D6S149. This gene is 24.5 kb and comprises of 8 exons. There are two transcripts with the shorter one due to splicing out of exon 4. It is expressed in testis, small intestine, spleen, prostate, and ovary. In a panel of 8 ovarian cancer cell lines, UNC93A expression was detected by RT-PCR which identified the two transcripts in 2/8 cell lines. The entire coding sequence was examined for mutations in a panel of ovarian tumours and ovarian cancer cell lines. Mutations were identified in exons 1, 3, 4, 5, 6 and 8. Only 3 mutations were identified specifically in the tumour. These included a c.452G>A (W151X mutation in exon 3, c.676C>T (R226X in exon 5 and c.1225G>A(V409I mutation in exon 8. However, the mutations in exon 3 and 5 were also present in 6% and 2% of the normal population respectively. The UNC93A cDNA was shown to express at the cell membrane and encodes for a protein of 60 kDa. Conclusions These results suggest that no evidence for UNC93A as a tumour suppressor gene in sporadic ovarian cancer has been identified and further research is required to evaluate its normal function and role in the pathogenesis of ovarian cancer.

  7. The first report of RPSA polymorphisms, also called 37/67 kDa LRP/LR gene, in sporadic Creutzfeldt-Jakob disease (CJD

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    Jeong Byung-Hoon

    2011-08-01

    Full Text Available Abstract Background Although polymorphisms of PRNP, the gene encoding prion protein, are known as a determinant affecting prion disease susceptibility, other genes also influence prion incubation time. This finding offers the opportunity to identify other genetic or environmental factor (s modulating susceptibility to prion disease. Ribosomal protein SA (RPSA, also called 37 kDa laminin receptor precursor (LRP/67 kDa laminin receptor (LR, acts as a receptor for laminin, viruses and prion proteins. The binding/internalization of prion protein is dependent for LRP/LR. Methods To identify other susceptibility genes involved in prion disease, we performed genetic analysis of RPSA. For this case-control study, we included 180 sporadic Creutzfeldt-Jakob disease (CJD patients and 189 healthy Koreans. We investigated genotype and allele frequencies of polymorphism on RPSA by direct sequencing or restriction fragment length polymorphism (RFLP analysis. Results We observed four single nucleotide polymorphisms (SNPs, including -8T>C (rs1803893 in the 5'-untranslated region (UTR of exon 2, 134-32C>T (rs3772138 in the intron, 519G>A (rs2269350 in the intron and 793+58C>T (rs2723 in the intron on the RPSA. The 519G>A (at codon 173 is located in the direct PrP binding site. The genotypes and allele frequencies of the RPSA polymorphisms showed no significant differences between the controls and sporadic CJD patients. Conclusion These results suggest that these RPSA polymorphisms have no direct influence on the susceptibility to sporadic CJD. This was the first genetic association study of the polymorphisms of RPSA gene with sporadic CJD.

  8. Instability of buried hydration sites increases protein subdomains fluctuations in the human prion protein by the pathogenic mutation T188R

    Science.gov (United States)

    Tomobe, Katsufumi; Yamamoto, Eiji; Akimoto, Takuma; Yasui, Masato; Yasuoka, Kenji

    2016-05-01

    The conformational change from the cellular prion protein (PrPc) to scrapie prion protein (PrPsc) is a key process in prion diseases. The prion protein has buried water molecules which significantly contribute to the stability of the protein; however, there has been no report investigating the influence on the buried hydration sites by a pathogenic mutation not adjacent to the buried hydration sites. Here, we perform molecular dynamics simulations of wild type (WT) PrPc and pathogenic point mutant T188R to investigate conformational changes and the buried hydration sites. In WT-PrPc, four buried hydration sites are identified by residence time and rotational relaxation analysis. However, there are no stable buried hydration sites in one of T188R simulations, which indicates that T188R sometimes makes the buried hydration sites fragile. We also find that fluctuations of subdomains S1-H1-S2 and H1-H2 increase in T188R when the buried hydration sites become unstable. Since the side chain of arginine which is replaced from threonine in T188R is larger than of threonine, the side chain cannot be embedded in the protein, which is one of the causes of the instability of subdomains. These results show correlations between the buried hydration sites and the mutation which is far from them, and provide a possible explanation for the instability by mutation.

  9. Instability of buried hydration sites increases protein subdomains fluctuations in the human prion protein by the pathogenic mutation T188R

    Directory of Open Access Journals (Sweden)

    Katsufumi Tomobe

    2016-05-01

    Full Text Available The conformational change from the cellular prion protein (PrPc to scrapie prion protein (PrPsc is a key process in prion diseases. The prion protein has buried water molecules which significantly contribute to the stability of the protein; however, there has been no report investigating the influence on the buried hydration sites by a pathogenic mutation not adjacent to the buried hydration sites. Here, we perform molecular dynamics simulations of wild type (WT PrPc and pathogenic point mutant T188R to investigate conformational changes and the buried hydration sites. In WT-PrPc, four buried hydration sites are identified by residence time and rotational relaxation analysis. However, there are no stable buried hydration sites in one of T188R simulations, which indicates that T188R sometimes makes the buried hydration sites fragile. We also find that fluctuations of subdomains S1-H1-S2 and H1-H2 increase in T188R when the buried hydration sites become unstable. Since the side chain of arginine which is replaced from threonine in T188R is larger than of threonine, the side chain cannot be embedded in the protein, which is one of the causes of the instability of subdomains. These results show correlations between the buried hydration sites and the mutation which is far from them, and provide a possible explanation for the instability by mutation.

  10. Orthogonal typing methods identify genetic diversity among Belgian Campylobacter jejuni strains isolated over a decade from poultry and cases of sporadic human illness.

    Science.gov (United States)

    Elhadidy, Mohamed; Arguello, Hector; Álvarez-Ordóñez, Avelino; Miller, William G; Duarte, Alexandra; Martiny, Delphine; Hallin, Marie; Vandenberg, Olivier; Dierick, Katelijne; Botteldoorn, Nadine

    2018-06-20

    Campylobacter jejuni is a zoonotic pathogen commonly associated with human gastroenteritis. Retail poultry meat is a major food-related transmission source of C. jejuni to humans. The present study investigated the genetic diversity, clonal relationship, and strain risk-analysis of 403 representative C. jejuni isolates from chicken broilers (n = 204) and sporadic cases of human diarrhea (n = 199) over a decade (2006-2015) in Belgium, using multilocus sequence typing (MLST), PCR binary typing (P-BIT), and identification of lipooligosaccharide (LOS) biosynthesis locus classes. A total of 123 distinct sequence types (STs), clustered in 28 clonal complexes (CCs) were assigned, including ten novel sequence types that were not previously documented in the international database. Sequence types ST-48, ST-21, ST-50, ST-45, ST-464, ST-2274, ST-572, ST-19, ST-257 and ST-42 were the most prevalent. Clonal complex 21 was the main clonal complex in isolates from humans and chickens. Among observed STs, a total of 35 STs that represent 72.2% (291/403) of the isolates were identified in both chicken and human isolates confirming considerable epidemiological relatedness; these 35 STs also clustered together in the most prevalent CCs. A majority of the isolates harbored sialylated LOS loci associated with potential neuropathic outcomes in humans. Although the concordance between MLST and P-BIT, determined by the adjusted Rand and Wallace coefficients, showed low congruence between both typing methods. The discriminatory power of P-BIT and MLST was similar, with Simpson's diversity indexes of 0.978 and 0.975, respectively. Furthermore, P-BIT could provide additional epidemiological information that would provide further insights regarding the potential association to human health from each strain. In addition, certain clones could be linked to specific clinical symptoms. Indeed, LOS class E was associated with less severe infections. Moreover, ST-572 was significantly

  11. White matter involvement in sporadic Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Caverzasi, Eduardo; Mandelli, Maria Luisa; DeArmond, Stephen J; Hess, Christopher P; Vitali, Paolo; Papinutto, Nico; Oehler, Abby; Miller, Bruce L; Lobach, Irina V; Bastianello, Stefano; Geschwind, Michael D; Henry, Roland G

    2014-12-01

    Sporadic Creutzfeldt-Jakob disease is considered primarily a disease of grey matter, although the extent of white matter involvement has not been well described. We used diffusion tensor imaging to study the white matter in sporadic Creutzfeldt-Jakob disease compared to healthy control subjects and to correlated magnetic resonance imaging findings with histopathology. Twenty-six patients with sporadic Creutzfeldt-Jakob disease and nine age- and gender-matched healthy control subjects underwent volumetric T1-weighted and diffusion tensor imaging. Six patients had post-mortem brain analysis available for assessment of neuropathological findings associated with prion disease. Parcellation of the subcortical white matter was performed on 3D T1-weighted volumes using Freesurfer. Diffusion tensor imaging maps were calculated and transformed to the 3D-T1 space; the average value for each diffusion metric was calculated in the total white matter and in regional volumes of interest. Tract-based spatial statistics analysis was also performed to investigate the deeper white matter tracts. There was a significant reduction of mean (P=0.002), axial (P=0.0003) and radial (P=0.0134) diffusivities in the total white matter in sporadic Creutzfeldt-Jakob disease. Mean diffusivity was significantly lower in most white matter volumes of interest (PCreutzfeldt-Jakob disease. Mean diffusivity reduction reflected concomitant decrease of both axial and radial diffusivity, without appreciable changes in white matter anisotropy. Tract-based spatial statistics analysis showed significant reductions of mean diffusivity within the white matter of patients with sporadic Creutzfeldt-Jakob disease, mainly in the left hemisphere, with a strong trend (P=0.06) towards reduced mean diffusivity in most of the white matter bilaterally. In contrast, by visual assessment there was no white matter abnormality either on T2-weighted or diffusion-weighted images. Widespread reduction in white matter mean

  12. Sporadic Creutzfeldt-Jakob Disease MM1+2C and MM1 are Identical in Transmission Properties.

    Science.gov (United States)

    Kobayashi, Atsushi; Matsuura, Yuichi; Iwaki, Toru; Iwasaki, Yasushi; Yoshida, Mari; Takahashi, Hitoshi; Murayama, Shigeo; Takao, Masaki; Kato, Shinsuke; Yamada, Masahito; Mohri, Shirou; Kitamoto, Tetsuyuki

    2016-01-01

    The genotype (methionine, M or valine, V) at polymorphic codon 129 of the PRNP gene and the type (1 or 2) of abnormal prion protein in the brain are the major determinants of the clinicopathological features of sporadic Creutzfeldt-Jakob disease (CJD), thus providing molecular basis for classification of sporadic CJD, that is, MM1, MM2, MV1, MV2, VV1 or VV2. In addition to these "pure" cases, "mixed" cases presenting mixed neuropathological and biochemical features have also been recognized. The most frequently observed mixed form is the co-occurrence of MM1 and MM2, namely MM1+2. However, it has remained elusive whether MM1+2 could be a causative origin of dura mater graft-associated CJD (dCJD), one of the largest subgroups of iatrogenic CJD. To test this possibility, we performed transmission experiments of MM1+2 prions and a systematic neuropathological examination of dCJD patients in the present study. The transmission properties of the MM1+2 prions were identical to those of MM1 prions because MM2 prions lacked transmissibility. In addition, the neuropathological characteristics of MM2 were totally absent in dCJD patients examined. These results suggest that MM1+2 can be a causative origin of dCJD and causes neuropathological phenotype similar to that of MM1. © 2015 International Society of Neuropathology.

  13. Prions and neuro degenerative diseases | Nair | African Journal of ...

    African Journals Online (AJOL)

    Prion is a disease-causing agent that is neither bacterial nor fungal nor viral and contains no genetic material. A prion is a protein that occurs normally in a harmless form. By folding into an aberrant shape, the normal prion turns into a rogue agent. It then co-opts other normal prions to become rogue prions. Prions have ...

  14. Statistical Mechanics of Prion Diseases

    International Nuclear Information System (INIS)

    Slepoy, A.; Singh, R. R. P.; Pazmandi, F.; Kulkarni, R. V.; Cox, D. L.

    2001-01-01

    We present a two-dimensional, lattice based, protein-level statistical mechanical model for prion diseases (e.g., mad cow disease) with concomitant prion protein misfolding and aggregation. Our studies lead us to the hypothesis that the observed broad incubation time distribution in epidemiological data reflect fluctuation dominated growth seeded by a few nanometer scale aggregates, while much narrower incubation time distributions for innoculated lab animals arise from statistical self-averaging. We model ''species barriers'' to prion infection and assess a related treatment protocol

  15. Lack of prion transmission by sexual or parental routes in experimentally infected hamsters.

    Science.gov (United States)

    Morales, Rodrigo; Pritzkow, Sandra; Hu, Ping Ping; Duran-Aniotz, Claudia; Soto, Claudio

    2013-01-01

    Prion diseases are a group of neurodegenerative disorders affecting humans as well as captive and wild animals. The mechanisms and routes governing the natural spread of prions are not completely understood and several hypotheses have been proposed. In this study, we analyzed the effect of gender in prion incubation period, as well as the possibility of prion transmission by sexual and parental contact using 263K infected hamsters as a model. Our results show that males have significantly longer incubation periods compared with females when exposed to the same quantity of infectious material. Importantly, no evidence of sexual or parental prion transmission was found, even 500 d after sexual contact or birth, respectively. Western blotting and PMCA were unable to detect sub-clinical levels of PrP(Sc) in experimental subjects, suggesting a complete absence of prion transmission by these routes. Our results show that sexual and parental transmission of prions does not occur in this model. It remains to be studied whether this conclusion is valid also for other prion strains and species.

  16. Synthetic Prions Provide Clues for Understanding Prion Diseases.

    Science.gov (United States)

    Imberdis, Thibaut; Harris, David A

    2016-04-01

    This Commentary highlights the article by Makarava et al that discusses the formation of synthetic prions and the role of substrate levels in their evolution. Copyright © 2016 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  17. Advancing prion science: guidance for the National Prion Research Program

    National Research Council Canada - National Science Library

    Erdtmann, Rick; Sivitz, Laura

    2004-01-01

    In Advancing Prion Science , the Institute of Medicine’s Committee on Transmissible Spongiform Encephalopathies Assessment of Relevant Science recommends priorities for research and investment to the Department of Defenseâ...

  18. Assessment of the PrPc Amino-Terminal Domain in Prion Species Barriers.

    Science.gov (United States)

    Davenport, Kristen A; Henderson, Davin M; Mathiason, Candace K; Hoover, Edward A

    2016-12-01

    Chronic wasting disease (CWD) in cervids and bovine spongiform encephalopathy (BSE) in cattle are prion diseases that are caused by the same protein-misfolding mechanism, but they appear to pose different risks to humans. We are interested in understanding the differences between the species barriers of CWD and BSE. We used real-time, quaking-induced conversion (RT-QuIC) to model the central molecular event in prion disease, the templated misfolding of the normal prion protein, PrP c , to a pathogenic, amyloid isoform, scrapie prion protein, PrP Sc We examined the role of the PrP c amino-terminal domain (N-terminal domain [NTD], amino acids [aa] 23 to 90) in cross-species conversion by comparing the conversion efficiency of various prion seeds in either full-length (aa 23 to 231) or truncated (aa 90 to 231) PrP c We demonstrate that the presence of white-tailed deer and bovine NTDs hindered seeded conversion of PrP c , but human and bank vole NTDs did the opposite. Additionally, full-length human and bank vole PrP c s were more likely to be converted to amyloid by CWD prions than were their truncated forms. A chimera with replacement of the human NTD by the bovine NTD resembled human PrP c The requirement for an NTD, but not for the specific human sequence, suggests that the NTD interacts with other regions of the human PrP c to increase promiscuity. These data contribute to the evidence that, in addition to primary sequence, prion species barriers are controlled by interactions of the substrate NTD with the rest of the substrate PrP c molecule. We demonstrate that the amino-terminal domain of the normal prion protein, PrP c , hinders seeded conversion of bovine and white-tailed deer PrP c s to the prion forms, but it facilitates conversion of the human and bank vole PrP c s to the prion forms. Additionally, we demonstrate that the amino-terminal domain of human and bank vole PrP c s requires interaction with the rest of the molecule to facilitate conversion by CWD

  19. Key points concerning amyloid infectivity and prion-like neuronal invasion

    Directory of Open Access Journals (Sweden)

    Alba eEspargaró

    2016-04-01

    Full Text Available Amyloid aggregation has been related to an increasing number of human illnesses, from Alzheimer and Parkinson’s diseases to Creutzfeldt-Jakob disease. Traditionally only prions have been considered as infectious agents with a high capacity of propagation. Although recent publications have showed that many amyloid proteins, including amyloid β-peptide, α-synuclein and tau protein, also propagate in a prion-like manner, the link between propagation of pathological proteins and neurotoxicity has not been evidenced. The extremely low infectivity in natural conditions of the most of non-prion amyloids is far from the spreading capacity displayed by the prions. However, it is important to elucidate the key factors that cause non-prion amyloids become infectious agents. In recent years, important advances in the understanding of the amyloid processes of amyloid-like proteins and unrelated prions (i.e., yeast and fungal prions have yielded essential information that can be applied to shed light on the prion phenomenon in mammals and humans. As shown in this review, recent evidences suggest that there are key factors that could dramatically modulate the prion capacity of proteins in the amyloid conformation. The concentration of nuclei, the presence of oligomers, and the toxicity, resistance and localization of these aggregates could be key factors affecting their spreading. In short, those factors that favor the high concentration of extracellular nuclei or oligomers, characterized by a small size, with a low toxicity could dramatically increase prion propensity; whereas low concentrations of highly toxic intracellular amyloids, with a large size, would prevent infectivity.

  20. Phosphatidylinositol-glycan-phospholipase D is involved in neurodegeneration in prion disease.

    Directory of Open Access Journals (Sweden)

    Jae-Kwang Jin

    Full Text Available PrPSc is formed from a normal glycosylphosphatidylinositol (GPI-anchored prion protein (PrPC by a posttranslational modification. Most GPI-anchored proteins have been shown to be cleaved by GPI phospholipases. Recently, GPI-phospholipase D (GPI-PLD was shown to be a strictly specific enzyme for GPI anchors. To investigate the involvement of GPI-PLD in the processes of neurodegeneration in prion diseases, we examined the mRNA and protein expression levels of GPI-PLD in the brains of a prion animal model (scrapie, and in both the brains and cerebrospinal fluids (CSF of sporadic and familial Creutzfeldt-Jakob disease (CJD patients. We found that compared with controls, the expression of GPI-PLD was dramatically down-regulated in the brains of scrapie-infected mice, especially in the caveolin-enriched membrane fractions. Interestingly, the observed decrease in GPI-PLD expression levels began at the same time that PrPSc began to accumulate in the infected brains and this decrease was also observed in both the brain and CSF of CJD patients; however, no differences in expression were observed in either the brains or CSF specimens from Alzheimer's disease patients. Taken together, these results suggest that the down-regulation of GPI-PLD protein may be involved in prion propagation in the brains of prion diseases.

  1. Human Noroviruses and Sporadic Gastroenteritis

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dan Rutz speaks with Dr. Manish Patel, a medical officer with the Division of Viral Diseases at CDC, about an article in August 2008 issue of Emerging Infectious Diseases reporting on nororviruses. Dr. Patel reviewed 235 studies and identified 31 original studies about noroviruses. Norovirus is the leading cause of epidemic gastroenteritis.

  2. Human Noroviruses and Sporadic Gastroenteritis

    Centers for Disease Control (CDC) Podcasts

    2008-08-05

    In this podcast, Dan Rutz speaks with Dr. Manish Patel, a medical officer with the Division of Viral Diseases at CDC, about an article in August 2008 issue of Emerging Infectious Diseases reporting on nororviruses. Dr. Patel reviewed 235 studies and identified 31 original studies about noroviruses. Norovirus is the leading cause of epidemic gastroenteritis.  Created: 8/5/2008 by Emerging Infectious Diseases.   Date Released: 7/30/2008.

  3. Meat and bone meal and mineral feed additives may increase the risk of oral prion disease transmission

    Science.gov (United States)

    Johnson, Christopher J.; McKenzie, Debbie; Pedersen, Joel A.; Aiken, Judd M.

    2011-01-01

    Ingestion of prion-contaminated materials is postulated to be a primary route of prion disease transmission. Binding of prions to soil (micro)particles dramatically enhances peroral disease transmission relative to unbound prions, and it was hypothesized that micrometer-sized particles present in other consumed materials may affect prion disease transmission via the oral route of exposure. Small, insoluble particles are present in many substances, including soil, human foods, pharmaceuticals, and animal feeds. It is known that meat and bone meal (MBM), a feed additive believed responsible for the spread of bovine spongiform encephalopathy (BSE), contains particles smaller than 20 μm and that the pathogenic prion protein binds to MBM. The potentiation of disease transmission via the oral route by exposure to MBM or three micrometer-sized mineral feed additives was determined. Data showed that when the disease agent was bound to any of the tested materials, the penetrance of disease was increased compared to unbound prions. Our data suggest that in feed or other prion-contaminated substances consumed by animals or, potentially, humans, the addition of MBM or the presence of microparticles could heighten risks of prion disease acquisition.

  4. Detection and Localization of PrPSc in the Skeletal Muscle of Patients with Variant, Iatrogenic, and Sporadic Forms of Creutzfeldt-Jakob Disease

    Science.gov (United States)

    Peden, Alexander H.; Ritchie, Diane L.; Head, Mark W.; Ironside, James W.

    2006-01-01

    Variant Creutzfeldt-Jakob disease (vCJD) differs from other human prion diseases in that the pathogenic prion protein PrPSc can be detected to a greater extent at extraneuronal sites throughout the body, principally within lymphoid tissues. However, a recent study using a high-sensitivity Western blotting technique revealed low levels of PrPSc in skeletal muscle from a quarter of Swiss patients with sporadic CJD (sCJD). This posed the question of whether PrPSc in muscle could also be detected in vCJD, sCJD, and iatrogenic (iCJD) patients from other populations. Therefore, we have used the same high-sensitivity Western blotting technique, in combination with paraffin-embedded tissue blotting, to screen for PrPSc in muscle tissue specimens taken at autopsy from 49 CJD patients in the United Kingdom. These techniques identified muscle PrPSc in 8 of 17 vCJD, 7 of 26 sCJD, and 2 of 5 iCJD patients. Paraffin-embedded tissue blotting analysis showed PrPSc in skeletal muscle in localized anatomical structures that had the morphological and immunohistochemical characteristics of nerve fibers. The detection of PrPSc in muscle tissue from all forms of CJD indicates the possible presence of infectivity in these tissues, suggesting important implications for assessing the potential risk of iatrogenic spread via contaminated surgical instruments. PMID:16507908

  5. The expanded octarepeat domain selectively binds prions and disrupts homomeric prion protein interactions

    NARCIS (Netherlands)

    Leliveld, S. R.; Dame, R.T.; Wuite, G.J.L.; Stitz, L.; Korth, C.

    2006-01-01

    Insertion of additional octarepeats into the prion protein gene has been genetically linked to familial Creutzfeldt Jakob disease and hence to de novo generation of infectious prions. The pivotal event during prion formation is the conversion of the normal prion protein (PrP

  6. New variant of Creutzfeldt-Jakob (vCJD) disease and other human prion diseases under epidemiological surveillance in Brazil

    OpenAIRE

    Gattás, Vera Lúcia; Lima Neto, Antonio Silva; Dimech, George Santiago; Mancini, Denise; Cantarino, Ligia Maria; Marins, José Ricardo Pio; Luna, Expedito José Albuquerque

    2007-01-01

    Abstract To increase the timeliness of detection of human cases of the new variant of Creutzfeldt-Jakob disease (vCJD) and to reduce the risk of transmission, the Brazilian Ministry of Health has established and standardized rules and control measures. These include the definition of criteria for suspect cases, reporting, monitoring, and control measures for illness prevention and transmission. Guidelines to be used by the team of health care staff were published and distributed to health wor...

  7. Prions: Beyond a Single Protein

    Science.gov (United States)

    Das, Alvin S.

    2016-01-01

    SUMMARY Since the term protein was first coined in 1838 and protein was discovered to be the essential component of fibrin and albumin, all cellular proteins were presumed to play beneficial roles in plants and mammals. However, in 1967, Griffith proposed that proteins could be infectious pathogens and postulated their involvement in scrapie, a universally fatal transmissible spongiform encephalopathy in goats and sheep. Nevertheless, this novel hypothesis had not been evidenced until 1982, when Prusiner and coworkers purified infectious particles from scrapie-infected hamster brains and demonstrated that they consisted of a specific protein that he called a “prion.” Unprecedentedly, the infectious prion pathogen is actually derived from its endogenous cellular form in the central nervous system. Unlike other infectious agents, such as bacteria, viruses, and fungi, prions do not contain genetic materials such as DNA or RNA. The unique traits and genetic information of prions are believed to be encoded within the conformational structure and posttranslational modifications of the proteins. Remarkably, prion-like behavior has been recently observed in other cellular proteins—not only in pathogenic roles but also serving physiological functions. The significance of these fascinating developments in prion biology is far beyond the scope of a single cellular protein and its related disease. PMID:27226089

  8. An assessment of the long-term persistence of prion infectivity in aquatic environments

    International Nuclear Information System (INIS)

    Marín-Moreno, Alba; Espinosa, Juan-Carlos; Fernández-Borges, Natalia; Píquer, Juan; Girones, Rosina; Andreoletti, Olivier; Torres, Juan-María

    2016-01-01

    The environment plays a key role in horizontal transmission of prion diseases, since prions are extremely resistant to classical inactivation procedures. In prior work, we observed the high stability of bovine spongiform encephalopathy (BSE) infectivity when these prions were incubated in aqueous media such as phosphate-buffered saline (PBS) or wastewater for nearly nine months. As a continuation of this experiment, the same samples were maintained in PBS or wastewater for five additional years and residual BSE infectivity was assessed in bovine PrP C transgenic mice. Over this long time period (more than six years), BSE infectivity was reduced by three and one orders of magnitude in wastewater and PBS respectively. To rule out a possible agent specific effect, sheep scrapie prions were subjected to the same experimental protocol, using eight years as the experimental end-point. No significant reduction in scrapie infectivity was observed over the first nine months of wastewater incubation while PBS incubation for eight years only produced a two logarithmic unit reduction in infectivity. By contrast, the dynamics of PrP Res persistence was different, disappearing progressively over the first year. The long persistence of prion infectivity observed in this study for two different agents provides supporting evidence of the assumed high stability of these agents in aquatic environments and that environmental processes or conventional wastewater treatments with low retention times would have little impact on prion infectivity. These results could have great repercussions in terms of risk assessment and safety for animals and human populations. - Highlights: • Prion infectivity resists long term incubations in aquatic environments. • Infectivity persistence in wastewater is reduced when compared to PBS. • In this study PrPRes fails as a marker for prion detection. • Mice bioassay is the most powerful tool for assessing prion presence. • Wastewater conventional

  9. An assessment of the long-term persistence of prion infectivity in aquatic environments

    Energy Technology Data Exchange (ETDEWEB)

    Marín-Moreno, Alba; Espinosa, Juan-Carlos; Fernández-Borges, Natalia; Píquer, Juan [Centro de Investigación en Sanidad Animal, CISA-INIA, Carretera Algete-El Casar S/n, Valdeolmos, 28130 Madrid (Spain); Girones, Rosina [Department of Microbiology, University of Barcelona, Diagonal 643, 08028 Barcelona (Spain); Andreoletti, Olivier [UMR INRA-ENVT 1225, Interactions Hôte Agent Pathogène, Ecole Nationale Vétérinaire de Toulouse, Toulouse (France); Torres, Juan-María, E-mail: jmtorres@inia.es [Centro de Investigación en Sanidad Animal, CISA-INIA, Carretera Algete-El Casar S/n, Valdeolmos, 28130 Madrid (Spain)

    2016-11-15

    The environment plays a key role in horizontal transmission of prion diseases, since prions are extremely resistant to classical inactivation procedures. In prior work, we observed the high stability of bovine spongiform encephalopathy (BSE) infectivity when these prions were incubated in aqueous media such as phosphate-buffered saline (PBS) or wastewater for nearly nine months. As a continuation of this experiment, the same samples were maintained in PBS or wastewater for five additional years and residual BSE infectivity was assessed in bovine PrP{sup C} transgenic mice. Over this long time period (more than six years), BSE infectivity was reduced by three and one orders of magnitude in wastewater and PBS respectively. To rule out a possible agent specific effect, sheep scrapie prions were subjected to the same experimental protocol, using eight years as the experimental end-point. No significant reduction in scrapie infectivity was observed over the first nine months of wastewater incubation while PBS incubation for eight years only produced a two logarithmic unit reduction in infectivity. By contrast, the dynamics of PrP{sup Res} persistence was different, disappearing progressively over the first year. The long persistence of prion infectivity observed in this study for two different agents provides supporting evidence of the assumed high stability of these agents in aquatic environments and that environmental processes or conventional wastewater treatments with low retention times would have little impact on prion infectivity. These results could have great repercussions in terms of risk assessment and safety for animals and human populations. - Highlights: • Prion infectivity resists long term incubations in aquatic environments. • Infectivity persistence in wastewater is reduced when compared to PBS. • In this study PrPRes fails as a marker for prion detection. • Mice bioassay is the most powerful tool for assessing prion presence. • Wastewater

  10. Defining sporadic Creutzfeldt-Jakob disease strains and their transmission properties

    Science.gov (United States)

    Bishop, Matthew T.; Will, Robert G.; Manson, Jean C.

    2010-01-01

    The biological determinants of the phenotypic variation in sporadic Creutzfeldt-Jakob disease (sCJD) are unknown. To categorize sCJD cases, the prion protein (PrP) codon 129 genotype and the biochemical characteristics of the disease-associated form of PrP (PrPSc) can be combined to form six subgroups (MM1, MM2, MV1, MV2, VV1, and VV2). This classification largely correlates with the known variation in the clinical and pathological features of sCJD, with the MM1 and MV1 cases representing the “classic” phenotype of sCJD. To address how this classification relates to different strains of sCJD we have inoculated each subgroup of sCJD to a panel of mice expressing different forms of the human PRNP gene (129MM, 129VV, and 129MV). We have established that all subtypes are transmissible to at least one genotype of mouse, and both agent and host factors determine transmission efficiency and the form of PrPSc deposited in the brain. Moreover, we have identified four distinct strains of sCJD using our in vivo strain typing panel. PMID:20547859

  11. Inactivation of Prions and Amyloid Seeds with Hypochlorous Acid.

    Directory of Open Access Journals (Sweden)

    Andrew G Hughson

    2016-09-01

    Full Text Available Hypochlorous acid (HOCl is produced naturally by neutrophils and other cells to kill conventional microbes in vivo. Synthetic preparations containing HOCl can also be effective as microbial disinfectants. Here we have tested whether HOCl can also inactivate prions and other self-propagating protein amyloid seeds. Prions are deadly pathogens that are notoriously difficult to inactivate, and standard microbial disinfection protocols are often inadequate. Recommended treatments for prion decontamination include strongly basic (pH ≥~12 sodium hypochlorite bleach, ≥1 N sodium hydroxide, and/or prolonged autoclaving. These treatments are damaging and/or unsuitable for many clinical, agricultural and environmental applications. We have tested the anti-prion activity of a weakly acidic aqueous formulation of HOCl (BrioHOCl that poses no apparent hazard to either users or many surfaces. For example, BrioHOCl can be applied directly to skin and mucous membranes and has been aerosolized to treat entire rooms without apparent deleterious effects. Here, we demonstrate that immersion in BrioHOCl can inactivate not only a range of target microbes, including spores of Bacillus subtilis, but also prions in tissue suspensions and on stainless steel. Real-time quaking-induced conversion (RT-QuIC assays showed that BrioHOCl treatments eliminated all detectable prion seeding activity of human Creutzfeldt-Jakob disease, bovine spongiform encephalopathy, cervine chronic wasting disease, sheep scrapie and hamster scrapie; these findings indicated reductions of ≥103- to 106-fold. Transgenic mouse bioassays showed that all detectable hamster-adapted scrapie infectivity in brain homogenates or on steel wires was eliminated, representing reductions of ≥~105.75-fold and >104-fold, respectively. Inactivation of RT-QuIC seeding activity correlated with free chlorine concentration and higher order aggregation or destruction of proteins generally, including prion

  12. Prion Protein Self Interactions; a gateway to novel therapeutic strategies?

    NARCIS (Netherlands)

    Rigter, A.; Langeveld, J.P.M.; Zijderveld, van F.G.; Bossers, A.

    2010-01-01

    Transmissible spongiform encephalopathies (TSEs) or prion diseases are fatal neurodegenerative disorders and include among others Creutzfeldt–Jakob disease in humans, bovine spongiform encephalopathy (BSE) in cattle, and scrapie in sheep. The central event in disease development in TSEs is the

  13. The Gut-Associated Lymphoid Tissues in the Small Intestine, Not the Large Intestine, Play a Major Role in Oral Prion Disease Pathogenesis

    Science.gov (United States)

    Donaldson, David S.; Else, Kathryn J.

    2015-01-01

    ABSTRACT Prion diseases are infectious neurodegenerative disorders characterized by accumulations of abnormally folded cellular prion protein in affected tissues. Many natural prion diseases are acquired orally, and following exposure, the early replication of some prion isolates upon follicular dendritic cells (FDC) within gut-associated lymphoid tissues (GALT) is important for the efficient spread of disease to the brain (neuroinvasion). Prion detection within large intestinal GALT biopsy specimens has been used to estimate human and animal disease prevalence. However, the relative contributions of the small and large intestinal GALT to oral prion pathogenesis were unknown. To address this issue, we created mice that specifically lacked FDC-containing GALT only in the small intestine. Our data show that oral prion disease susceptibility was dramatically reduced in mice lacking small intestinal GALT. Although these mice had FDC-containing GALT throughout their large intestines, these tissues were not early sites of prion accumulation or neuroinvasion. We also determined whether pathology specifically within the large intestine might influence prion pathogenesis. Congruent infection with the nematode parasite Trichuris muris in the large intestine around the time of oral prion exposure did not affect disease pathogenesis. Together, these data demonstrate that the small intestinal GALT are the major early sites of prion accumulation and neuroinvasion after oral exposure. This has important implications for our understanding of the factors that influence the risk of infection and the preclinical diagnosis of disease. IMPORTANCE Many natural prion diseases are acquired orally. After exposure, the accumulation of some prion diseases in the gut-associated lymphoid tissues (GALT) is important for efficient spread of disease to the brain. However, the relative contributions of GALT in the small and large intestines to oral prion pathogenesis were unknown. We show that the

  14. The Gut-Associated Lymphoid Tissues in the Small Intestine, Not the Large Intestine, Play a Major Role in Oral Prion Disease Pathogenesis.

    Science.gov (United States)

    Donaldson, David S; Else, Kathryn J; Mabbott, Neil A

    2015-09-01

    Prion diseases are infectious neurodegenerative disorders characterized by accumulations of abnormally folded cellular prion protein in affected tissues. Many natural prion diseases are acquired orally, and following exposure, the early replication of some prion isolates upon follicular dendritic cells (FDC) within gut-associated lymphoid tissues (GALT) is important for the efficient spread of disease to the brain (neuroinvasion). Prion detection within large intestinal GALT biopsy specimens has been used to estimate human and animal disease prevalence. However, the relative contributions of the small and large intestinal GALT to oral prion pathogenesis were unknown. To address this issue, we created mice that specifically lacked FDC-containing GALT only in the small intestine. Our data show that oral prion disease susceptibility was dramatically reduced in mice lacking small intestinal GALT. Although these mice had FDC-containing GALT throughout their large intestines, these tissues were not early sites of prion accumulation or neuroinvasion. We also determined whether pathology specifically within the large intestine might influence prion pathogenesis. Congruent infection with the nematode parasite Trichuris muris in the large intestine around the time of oral prion exposure did not affect disease pathogenesis. Together, these data demonstrate that the small intestinal GALT are the major early sites of prion accumulation and neuroinvasion after oral exposure. This has important implications for our understanding of the factors that influence the risk of infection and the preclinical diagnosis of disease. Many natural prion diseases are acquired orally. After exposure, the accumulation of some prion diseases in the gut-associated lymphoid tissues (GALT) is important for efficient spread of disease to the brain. However, the relative contributions of GALT in the small and large intestines to oral prion pathogenesis were unknown. We show that the small intestinal

  15. Probing Early Misfolding Events in Prion Protein Mutants by NMR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Gregor Ilc

    2013-08-01

    Full Text Available The post-translational conversion of the ubiquitously expressed cellular form of the prion protein, PrPC, into its misfolded and pathogenic isoform, known as prion or PrPSc, plays a key role in prion diseases. These maladies are denoted transmissible spongiform encephalopathies (TSEs and affect both humans and animals. A prerequisite for understanding TSEs is unraveling the molecular mechanism leading to the conversion process whereby most α-helical motifs are replaced by β-sheet secondary structures. Importantly, most point mutations linked to inherited prion diseases are clustered in the C-terminal domain region of PrPC and cause spontaneous conversion to PrPSc. Structural studies with PrP variants promise new clues regarding the proposed conversion mechanism and may help identify “hot spots” in PrPC involved in the pathogenic conversion. These investigations may also shed light on the early structural rearrangements occurring in some PrPC epitopes thought to be involved in modulating prion susceptibility. Here we present a detailed overview of our solution-state NMR studies on human prion protein carrying different pathological point mutations and the implications that such findings may have for the future of prion research.

  16. Prion-Like Domains in Phagobiota

    Directory of Open Access Journals (Sweden)

    George Tetz

    2017-11-01

    Full Text Available Prions are molecules characterized by self-propagation, which can undergo a conformational switch leading to the creation of new prions. Prion proteins have originally been associated with the development of mammalian pathologies; however, recently they have been shown to contribute to the environmental adaptation in a variety of prokaryotic and eukaryotic organisms. Bacteriophages are widespread and represent the important regulators of microbiota homeostasis and have been shown to be diverse across various bacterial families. Here, we examined whether bacteriophages contain prion-like proteins and whether these prion-like protein domains are involved in the regulation of homeostasis. We used a computational algorithm, prion-like amino acid composition, to detect prion-like domains in 370,617 publicly available bacteriophage protein sequences, which resulted in the identification of 5040 putative prions. We analyzed a set of these prion-like proteins, and observed regularities in their distribution across different phage families, associated with their interactions with the bacterial host cells. We found that prion-like domains could be found across all phages of various groups of bacteria and archaea. The results obtained in this study indicate that bacteriophage prion-like proteins are predominantly involved in the interactions between bacteriophages and bacterial cell, such as those associated with the attachment and penetration of bacteriophage in the cell, and the release of the phage progeny. These data allow the identification of phage prion-like proteins as novel regulators of the interactions between bacteriophages and bacterial cells.

  17. Modulation of prion polymerization and toxicity by rationally designed peptidomimetics.

    Science.gov (United States)

    Srivastava, Ankit; Sharma, Sakshi; Sadanandan, Sandhya; Gupta, Sakshi; Singh, Jasdeep; Gupta, Sarika; Haridas, V; Kundu, Bishwajit

    2017-01-01

    Misfolding and aggregation of cellular prion protein is associated with a large array of neurological disorders commonly called the transmissible spongiform encephalopathies. Designing inhibitors against prions has remained a daunting task owing to limited information about mechanism(s) of their pathogenic self-assembly. Here, we explore the anti-prion properties of a combinatorial library of bispidine-based peptidomimetics (BPMs) that conjugate amino acids with hydrophobic and aromatic side chains. Keeping the bispidine unit unaltered, a series of structurally diverse BPMs were synthesized and tested for their prion-modulating properties. Administration of Leu- and Trp-BPMs delayed and completely inhibited the amyloidogenic conversion of human prion protein (HuPrP), respectively. We found that each BPM induced the HuPrP to form unique oligomeric nanostructures differing in their biophysical properties, cellular toxicities and response to conformation-specific antibodies. While Leu-BPMs were found to stabilize the oligomers, Trp-BPMs effected transient oligomerization, resulting in the formation of non-toxic, non-fibrillar aggregates. Yet another aromatic residue, Phe, however, accelerated the aggregation process in HuPrP. Molecular insights obtained through MD (molecular dynamics) simulations suggested that each BPM differently engages a conserved Tyr 169 residue at the α2-β2 loop of HuPrP and affects the stability of α2 and α3 helices. Our results demonstrate that this new class of molecules having chemical scaffolds conjugating hydrophobic/aromatic residues could effectively modulate prion aggregation and toxicity. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  18. Homogenous photocatalytic decontamination of prion infected stainless steel and titanium surfaces.

    Science.gov (United States)

    Berberidou, Chrysanthi; Xanthopoulos, Konstantinos; Paspaltsis, Ioannis; Lourbopoulos, Athanasios; Polyzoidou, Eleni; Sklaviadis, Theodoros; Poulios, Ioannis

    2013-01-01

    Prions are notorious for their extraordinary resistance to traditional methods of decontamination, rendering their transmission a public health risk. Iatrogenic Creutzfeldt-Jakob disease (iCJD) via contaminated surgical instruments and medical devices has been verified both experimentally and clinically. Standard methods for prion inactivation by sodium hydroxide or sodium hypochlorite have failed, in some cases, to fully remove prion infectivity, while they are often impractical for routine applications. Prion accumulation in peripheral tissues and indications of human-to-human bloodborne prion transmission, highlight the need for novel, efficient, yet user-friendly methods of prion inactivation. Here we show both in vitro and in vivo that homogenous photocatalytic oxidation, mediated by the photo-Fenton reagent, has the potential to inactivate the pathological prion isoform adsorbed on metal substrates. Photocatalytic oxidation with 224 μg mL(-1) Fe (3+), 500 μg mL(-1) h(-1) H 2O 2, UV-A for 480 min lead to 100% survival in golden Syrian hamsters after intracranial implantation of stainless steel wires infected with the 263K prion strain. Interestingly, photocatalytic treatment of 263K infected titanium wires, under the same experimental conditions, prolonged the survival interval significantly, but failed to eliminate infectivity, a result that we correlate with the increased adsorption of PrP(Sc) on titanium, in comparison to stainless steel. Our findings strongly indicate that our, user--and environmentally--friendly protocol can be safely applied to the decontamination of prion infected stainless steel surfaces.

  19. Yeast prions assembly and propagation: contributions of the prion and non-prion moieties and the nature of assemblies.

    Science.gov (United States)

    Kabani, Mehdi; Melki, Ronald

    2011-01-01

    Yeast prions are self-perpetuating protein aggregates that are at the origin of heritable and transmissible non-Mendelian phenotypic traits. Among these, [PSI+], [URE3] and [PIN+] are the most well documented prions and arise from the assembly of Sup35p, Ure2p and Rnq1p, respectively, into insoluble fibrillar assemblies. Fibril assembly depends on the presence of N- or C-terminal prion domains (PrDs) which are not homologous in sequence but share unusual amino-acid compositions, such as enrichment in polar residues (glutamines and asparagines) or the presence of oligopeptide repeats. Purified PrDs form amyloid fibrils that can convert prion-free cells to the prion state upon transformation. Nonetheless, isolated PrDs and full-length prion proteins have different aggregation, structural and infectious properties. In addition, mutations in the "non-prion" domains (non-PrDs) of Sup35p, Ure2p and Rnq1p were shown to affect their prion properties in vitro and in vivo. Despite these evidences, the implication of the functional non-PrDs in fibril assembly and prion propagation has been mostly overlooked. In this review, we discuss the contribution of non-PrDs to prion assemblies, and the structure-function relationship in prion infectivity in the light of recent findings on Sup35p and Ure2p assembly into infectious fibrils from our laboratory and others.

  20. A brief history of prions

    Science.gov (United States)

    Zabel, Mark D.; Reid, Crystal

    2015-01-01

    Proteins were described as distinct biological molecules and their significance in cellular processes was recognized as early as the 18th century. At the same time, Spanish shepherds observed a disease that compelled their Merino sheep to pathologically scrape against fences, a defining clinical sign that led to the disease being named scrapie. In the late 19th century, Robert Koch published his postulates for defining causative agents of disease. In the early 20th century, pathologists Creutzfeldt and Jakob described a neurodegenerative disease that would later be included with scrapie into a group of diseases known as transmissible spongiform encephalopathies (TSEs). Later that century, mounting evidence compelled a handful of scientists to betray the prevailing biological dogma governing pathogen replication that Watson and Crick so convincingly explained by cracking the genetic code just two decades earlier. Because TSEs seemed to defy these new rules, J.S. Griffith theorized mechanisms by which a pathogenic protein could encipher its own replication blueprint without a genetic code. Stanley Prusiner called this proteinaceous infectious pathogen a prion. Here we offer a concise account of the discovery of prions, the causative agent of TSEs, in the wider context of protein biochemistry and infectious disease. We highlight the discovery of prions in yeast and discuss the implication of prions as epigenomic carriers of biological and pathological information. We also consider expanding the prion hypothesis to include other proteins whose alternate isoforms confer new biological or pathological properties. PMID:26449713

  1. Genetics Home Reference: sporadic hemiplegic migraine

    Science.gov (United States)

    ... Home Health Conditions Sporadic hemiplegic migraine Sporadic hemiplegic migraine Printable PDF Open All Close All Enable Javascript ... view the expand/collapse boxes. Description Sporadic hemiplegic migraine is a rare form of migraine headache. Migraines ...

  2. Screening of intact yeasts and cell extracts to reduce Scrapie prions during biotransformation of food waste.

    Science.gov (United States)

    Huyben, David; Boqvist, Sofia; Passoth, Volkmar; Renström, Lena; Allard Bengtsson, Ulrika; Andréoletti, Olivier; Kiessling, Anders; Lundh, Torbjörn; Vågsholm, Ivar

    2018-02-08

    Yeasts can be used to convert organic food wastes to protein-rich animal feed in order to recapture nutrients. However, the reuse of animal-derived waste poses a risk for the transmission of infectious prions that can cause neurodegeneration and fatality in humans and animals. The aim of this study was to investigate the ability of yeasts to reduce prion activity during the biotransformation of waste substrates-thereby becoming a biosafety hurdle in such a circular food system. During pre-screening, 30 yeast isolates were spiked with Classical Scrapie prions and incubated for 72 h in casein substrate, as a waste substitute. Based on reduced Scrapie seeding activity, waste biotransformation and protease activities, intact cells and cell extracts of 10 yeasts were further tested. Prion analysis showed that five yeast species reduced Scrapie seeding activity by approximately 1 log10 or 90%. Cryptococcus laurentii showed the most potential to reduce prion activity since both intact and extracted cells reduced Scrapie by 1 log10 and achieved the highest protease activity. These results show that select forms of yeast can act as a prion hurdle during the biotransformation of waste. However, the limited ability of yeasts to reduce prion activity warrants caution as a sole barrier to transmission as higher log reductions are needed before using waste-cultured yeast in circular food systems.

  3. The tip of the iceberg: RNA-binding proteins with prion-like domains in neurodegenerative disease

    Science.gov (United States)

    King, Oliver D.; Gitler, Aaron D.; Shorter, James

    2012-01-01

    Prions are self-templating protein conformers that are naturally transmitted between individuals and promote phenotypic change. In yeast, prion-encoded phenotypes can be beneficial, neutral or deleterious depending upon genetic background and environmental conditions. A distinctive and portable ‘prion domain’ enriched in asparagine, glutamine, tyrosine and glycine residues unifies the majority of yeast prion proteins. Deletion of this domain precludes prionogenesis and appending this domain to reporter proteins can confer prionogenicity. An algorithm designed to detect prion domains has successfully identified 19 domains that can confer prion behavior. Scouring the human genome with this algorithm enriches a select group of RNA-binding proteins harboring a canonical RNA recognition motif (RRM) and a putative prion domain. Indeed, of 210 human RRM-bearing proteins, 29 have a putative prion domain, and 12 of these are in the top 60 prion candidates in the entire genome. Startlingly, these RNA-binding prion candidates are inexorably emerging, one by one, in the pathology and genetics of devastating neurodegenerative disorders, including: amyotrophic lateral sclerosis (ALS), frontotemporal lobar degeneration with ubiquitin-positive inclusions (FTLD-U), Alzheimer’s disease and Huntington’s disease. For example, FUS and TDP-43, which rank 1st and 10th among RRM-bearing prion candidates, form cytoplasmic inclusions in the degenerating motor neurons of ALS patients and mutations in TDP-43 and FUS cause familial ALS. Recently, perturbed RNA-binding proteostasis of TAF15, which is the 2nd ranked RRM-bearing prion candidate, has been connected with ALS and FTLD-U. We strongly suspect that we have now merely reached the tip of the iceberg. We predict that additional RNA-binding prion candidates identified by our algorithm will soon surface as genetic modifiers or causes of diverse neurodegenerative conditions. Indeed, simple prion-like transfer mechanisms involving the

  4. Prying into the Prion Hypothesis for Parkinson's Disease.

    Science.gov (United States)

    Brundin, Patrik; Melki, Ronald

    2017-10-11

    In Parkinson's disease, intracellular α-synuclein inclusions form in neurons. We suggest that prion-like behavior of α-synuclein is a key component in Parkinson's disease pathogenesis. Although multiple molecular changes are involved in the triggering of the disease process, we propose that neuron-to-neuron transfer is a crucial event that is essential for Lewy pathology to spread from one brain region to another. In this review, we describe key findings in human postmortem brains, cultured cells, and animal models of disease that support the idea that α-synuclein can act as a prion. We consider potential triggers of the α-synuclein misfolding and why the aggregates escape cellular degradation under disease conditions. We also discuss whether different strains of α-synuclein fibrils can underlie differences in cellular and regional distribution of aggregates in different synucleinopathies. Our conclusion is that α-synuclein probably acts as a prion in human diseases, and a deeper understanding of this step in the pathogenesis of Parkinson's disease can facilitate the development of disease-modifying therapies in the future. Dual Perspectives Companion Paper: Parkinson's Disease Is Not Simply a Prion Disorder, by D. James Surmeier, José A. Obeso, and Glenda M. Halliday. Copyright © 2017 the authors 0270-6474/17/379808-11$15.00/0.

  5. Rapid and Highly Sensitive Detection of Variant Creutzfeldt-Jakob Disease Abnormal Prion Protein on Steel Surfaces by Protein Misfolding Cyclic Amplification: Application to Prion Decontamination Studies.

    Directory of Open Access Journals (Sweden)

    Maxime Belondrade

    Full Text Available The prevalence of variant Creutzfeldt-Jakob disease (vCJD in the population remains uncertain, although it has been estimated that 1 in 2000 people in the United Kingdom are positive for abnormal prion protein (PrPTSE by a recent survey of archived appendix tissues. The prominent lymphotropism of vCJD prions raises the possibility that some surgical procedures may be at risk of iatrogenic vCJD transmission in healthcare facilities. It is therefore vital that decontamination procedures applied to medical devices before their reprocessing are thoroughly validated. A current limitation is the lack of a rapid model permissive to human prions. Here, we developed a prion detection assay based on protein misfolding cyclic amplification (PMCA technology combined with stainless-steel wire surfaces as carriers of prions (Surf-PMCA. This assay allowed the specific detection of minute quantities (10-8 brain dilution of either human vCJD or ovine scrapie PrPTSE adsorbed onto a single steel wire, within a two week timeframe. Using Surf-PMCA we evaluated the performance of several reference and commercially available prion-specific decontamination procedures. Surprisingly, we found the efficiency of several marketed reagents to remove human vCJD PrPTSE was lower than expected. Overall, our results demonstrate that Surf-PMCA can be used as a rapid and ultrasensitive assay for the detection of human vCJD PrPTSE adsorbed onto a metallic surface, therefore facilitating the development and validation of decontamination procedures against human prions.

  6. Methamphetamine increases Prion Protein and induces dopamine-dependent expression of protease resistant PrPsc.

    Science.gov (United States)

    Ferrucci, M; Ryskalin, L; Biagioni, F; Gambardella, S; Busceti, C L; Falleni, A; Lazzeri, G; Fornai, F

    2017-07-01

    The cellular prion protein (PrPc) is physiologically expressed within selective brain areas of mammals. Alterations in the secondary structure of this protein lead to scrapie-like prion protein (PrPsc), which precipitates in the cell. PrPsc has been detected in infectious, inherited or sporadic neurodegenerative disorders. Prion protein metabolism is dependent on autophagy and ubiquitin proteasome. Despite not being fully elucidated, the physiological role of prion protein relates to chaperones which rescue cells under stressful conditions.Methamphetamine (METH) is a widely abused drug which produces oxidative stress in various brain areas causing mitochondrial alterations and protein misfolding. These effects produce a compensatory increase of chaperones while clogging cell clearing pathways. In the present study, we explored whether METH administration modifies the amount of PrPc. Since high levels of PrPc when the clearing systems are clogged may lead to its misfolding into PrPsc, we further tested whether METH exposure triggers the appearance of PrPsc. We analysed the effects of METH and dopamine administration in PC12 and striatal cells by using SDS-PAGE Coomassie blue, immune- histochemistry and immune-gold electron microscopy. To analyze whether METH administration produces PrPsc aggregates we used antibodies directed against PrP following exposure to proteinase K or sarkosyl which digest folded PrPc but misfolded PrPsc. We fond that METH triggers PrPsc aggregates in DA-containing cells while METH is not effective in primary striatal neurons which do not produce DA. In the latter cells exogenous DA is needed to trigger PrPsc accumulation similarly to what happens in DA containing cells under the effects of METH. The present findings, while fostering novel molecular mechanisms involving prion proteins, indicate that, cell pathology similar to prion disorders can be mimicked via a DA-dependent mechanism by a drug of abuse.

  7. Optimization of Aryl Amides that Extend Survival in Prion-Infected Mice.

    Science.gov (United States)

    Giles, Kurt; Berry, David B; Condello, Carlo; Dugger, Brittany N; Li, Zhe; Oehler, Abby; Bhardwaj, Sumita; Elepano, Manuel; Guan, Shenheng; Silber, B Michael; Olson, Steven H; Prusiner, Stanley B

    2016-09-01

    Developing therapeutics for neurodegenerative diseases (NDs) prevalent in the aging population remains a daunting challenge. With the growing understanding that many NDs progress by conformational self-templating of specific proteins, the prototypical prion diseases offer a platform for ND drug discovery. We evaluated high-throughput screening hits with the aryl amide scaffold and explored the structure-activity relationships around three series differing in their N-aryl core: benzoxazole, benzothiazole, and cyano. Potent anti-prion compounds were advanced to pharmacokinetic studies, and the resulting brain-penetrant leads from each series, together with a related N-aryl piperazine lead, were escalated to long-term dosing and efficacy studies. Compounds from each of the four series doubled the survival of mice infected with a mouse-passaged prion strain. Treatment with aryl amides altered prion strain properties, as evidenced by the distinct patterns of neuropathological deposition of prion protein and associated astrocytic gliosis in the brain; however, none of the aryl amide compounds resulted in drug-resistant prion strains, in contrast to previous studies on compounds with the 2-aminothiazole (2-AMT) scaffold. As seen with 2-AMTs and other effective anti-prion compounds reported to date, the novel aryl amides reported here were ineffective in prolonging the survival of transgenic mice infected with human prions. Most encouraging is our discovery that aryl amides show that the development of drug resistance is not an inevitable consequence of efficacious anti-prion therapeutics. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

  8. Prion diseases of the brain

    International Nuclear Information System (INIS)

    Lutz, Kira; Urbach, Horst

    2015-01-01

    The prion diseases of the brain, especially Creutzfeldt-Jakob disease, are rare fatal neurodegenerative disorders. A definitive CJD diagnosis is currently only possible by a brain biopsy or post mortem autopsy. The diagnosis of Creutzfeldt-Jakob disease is based on clinical signs, pathognomonic EEG, on typical MRI findings and the examination of the cerebrospinal fluid. Using the MRI the diagnosis Creutzfeldt-Jakob disease can be confirmed or excluded with high certainty. The MRI examination should contain diffusion-weighted and FLAIR imaging sequences. This review article provides an overview of the prion diseases of the brain with the corresponding imaging findings.

  9. Prion Protein Devoid of the Octapeptide Repeat Region Delays Bovine Spongiform Encephalopathy Pathogenesis in Mice.

    Science.gov (United States)

    Hara, Hideyuki; Miyata, Hironori; Das, Nandita Rani; Chida, Junji; Yoshimochi, Tatenobu; Uchiyama, Keiji; Watanabe, Hitomi; Kondoh, Gen; Yokoyama, Takashi; Sakaguchi, Suehiro

    2018-01-01

    Conformational conversion of the cellular isoform of prion protein, PrP C , into the abnormally folded, amyloidogenic isoform, PrP Sc , is a key pathogenic event in prion diseases, including Creutzfeldt-Jakob disease in humans and scrapie and bovine spongiform encephalopathy (BSE) in animals. We previously reported that the octapeptide repeat (OR) region could be dispensable for converting PrP C into PrP Sc after infection with RML prions. We demonstrated that mice transgenically expressing mouse PrP with deletion of the OR region on the PrP knockout background, designated Tg(PrPΔOR)/ Prnp 0 / 0 mice, did not show reduced susceptibility to RML scrapie prions, with abundant accumulation of PrP Sc ΔOR in their brains. We show here that Tg(PrPΔOR)/ Prnp 0 / 0 mice were highly resistant to BSE prions, developing the disease with markedly elongated incubation times after infection with BSE prions. The conversion of PrPΔOR into PrP Sc ΔOR was markedly delayed in their brains. These results suggest that the OR region may have a crucial role in the conversion of PrP C into PrP Sc after infection with BSE prions. However, Tg(PrPΔOR)/ Prnp 0 / 0 mice remained susceptible to RML and 22L scrapie prions, developing the disease without elongated incubation times after infection with RML and 22L prions. PrP Sc ΔOR accumulated only slightly less in the brains of RML- or 22L-infected Tg(PrPΔOR)/ Prnp 0 / 0 mice than PrP Sc in control wild-type mice. Taken together, these results indicate that the OR region of PrP C could play a differential role in the pathogenesis of BSE prions and RML or 22L scrapie prions. IMPORTANCE Structure-function relationship studies of PrP C conformational conversion into PrP Sc are worthwhile to understand the mechanism of the conversion of PrP C into PrP Sc We show here that, by inoculating Tg(PrPΔOR)/ Prnp 0 / 0 mice with the three different strains of RML, 22L, and BSE prions, the OR region could play a differential role in the conversion of

  10. Long-term preclinical magnetic resonance imaging alterations in sporadic Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Zanusso, Gianluigi; Camporese, Giulia; Ferrari, Sergio; Santelli, Luca; Bongianni, Matilde; Fiorini, Michele; Monaco, Salvatore; Manara, Renzo; Cagnin, Annachiara

    2016-10-01

    An asymptomatic 74-year-old woman, on follow-up for a carotid body tumor, showed magnetic resonance imaging (MRI) focal restricted diffusion confined to the left temporal and occipital cortices. Thirteen months later, diffusion-weighted images revealed a bilateral cortical ribbon sign involving all lobes. After 1 month, the patient developed gait instability and cognitive decline rapidly evolving to severe dementia and death within 3 months. Prion protein gene sequence, molecular, and neuropathological studies confirmed the diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) MM1 subtype. Here we show the kinetics of MRI changes and prion spreading in preclinical sCJD MM1. Ann Neurol 2016;80:629-632. © 2016 American Neurological Association.

  11. The inhibition of prions through blocking prion conversion by permanently charged branched polyamines of low cytotoxicity.

    Science.gov (United States)

    Lim, Yong-beom; Mays, Charles E; Kim, Younghwan; Titlow, William B; Ryou, Chongsuk

    2010-03-01

    Branched polyamines are effective in inhibiting prions in a cationic surface charge density dependent manner. However, toxicity associated with branched polyamines, in general, often hampers the successful application of the compounds to treat prion diseases. Here, we report that constitutively maintained cationic properties in branched polyamines reduced the intrinsic toxicity of the compounds while retaining the anti-prion activities. In prion-infected neuroblastoma cells, quaternization of amines in polyethyleneimine (PEI) and polyamidoamine (PAMAM) dendrimers markedly increased the nontoxic concentration ranges of the compounds and still supported, albeit reduced, an appreciable level of anti-prion activity in clearing prions from the infected cells. Furthermore, quaternized PEI was able to degrade prions at acidic pH conditions and inhibit the in vitro prion propagation facilitated by conversion of the normal prion protein isoform to its misfolded counterpart, although such activities were decreased by quaternization. Quaternized PAMAM was least effective in degrading prions but efficiently inhibited prion conversion with the same efficacy as unmodified PAMAM. Our results suggest that quaternization represents an effective strategy for developing nontoxic branched polyamines with potent anti-prion activity. This study highlights the importance of polyamine structural control for developing polyamine-based anti-prion agents and understanding of an action mechanism of quaternized branched polyamines. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  12. Prions And Prion Diseases | Obi | African Journal of Clinical and ...

    African Journals Online (AJOL)

    Patients also may experience involuntary jerking movements called myoclonus, unusual sensation, insomnia, and confusion or memory problems. In the later stages of the disease, patients may have severe mental impairment (dementia) and may lose the ability to move or speak. Well known prion diseases include scrapie ...

  13. Quinacrine reactivity with prion proteins and prion-derived peptides

    Czech Academy of Sciences Publication Activity Database

    Zawada, Zbigniew; Šafařík, Martin; Dvořáková, E.; Janoušková, O.; Březinová, Anna; Stibor, Ivan; Holada, K.; Bouř, Petr; Hlaváček, Jan; Šebestík, Jaroslav

    2013-01-01

    Roč. 44, č. 5 (2013), s. 1279-1292 ISSN 0939-4451 R&D Projects: GA ČR GA203/07/1517 Institutional support: RVO:61388963 Keywords : quinacrine * prion protein and peptide model reactions * solid phase and recombinant synthesis Subject RIV: CE - Biochemistry Impact factor: 3.653, year: 2013

  14. Prion protein self-interaction in prion disease therapy approaches

    NARCIS (Netherlands)

    Rigter, A.; Priem, J.; Langeveld, J.P.M.; Bossers, A.

    2011-01-01

    Transmissible spongiform encephalopathies (TSEs) or prion diseases are unique disorders that are not caused by infectious micro-organisms (bacteria or fungi), viruses or parasites, but rather seem to be the result of an infectious protein. TSEs are comprised of fatal neurodegenerative disorders

  15. Cellular Aspects of Prion Replication In Vitro

    Science.gov (United States)

    Grassmann, Andrea; Wolf, Hanna; Hofmann, Julia; Graham, James; Vorberg, Ina

    2013-01-01

    Prion diseases or transmissible spongiform encephalopathies (TSEs) are fatal neurodegenerative disorders in mammals that are caused by unconventional agents predominantly composed of aggregated misfolded prion protein (PrP). Prions self-propagate by recruitment of host-encoded PrP into highly ordered β-sheet rich aggregates. Prion strains differ in their clinical, pathological and biochemical characteristics and are likely to be the consequence of distinct abnormal prion protein conformers that stably replicate their alternate states in the host cell. Understanding prion cell biology is fundamental for identifying potential drug targets for disease intervention. The development of permissive cell culture models has greatly enhanced our knowledge on entry, propagation and dissemination of TSE agents. However, despite extensive research, the precise mechanism of prion infection and potential strain effects remain enigmatic. This review summarizes our current knowledge of the cell biology and propagation of prions derived from cell culture experiments. We discuss recent findings on the trafficking of cellular and pathologic PrP, the potential sites of abnormal prion protein synthesis and potential co-factors involved in prion entry and propagation. PMID:23340381

  16. A closer look at prion strains

    Science.gov (United States)

    Solforosi, Laura; Milani, Michela; Mancini, Nicasio; Clementi, Massimo; Burioni, Roberto

    2013-01-01

    Prions are infectious proteins that are responsible for transmissible spongiform encephalopathies (TSEs) and consist primarily of scrapie prion protein (PrPSc), a pathogenic isoform of the host-encoded cellular prion protein (PrPC). The absence of nucleic acids as essential components of the infectious prions is the most striking feature associated to these diseases. Additionally, different prion strains have been isolated from animal diseases despite the lack of DNA or RNA molecules. Mounting evidence suggests that prion-strain-specific features segregate with different PrPSc conformational and aggregation states. Strains are of practical relevance in prion diseases as they can drastically differ in many aspects, such as incubation period, PrPSc biochemical profile (e.g., electrophoretic mobility and glycoform ratio) and distribution of brain lesions. Importantly, such different features are maintained after inoculation of a prion strain into genetically identical hosts and are relatively stable across serial passages. This review focuses on the characterization of prion strains and on the wide range of important implications that the study of prion strains involves. PMID:23357828

  17. Use of bovine recombinant prion protein and real-time quaking-induced conversion to detect cattle transmissible mink encephalopathy prions and discriminate classical and atypical L- and H-Type bovine spongiform encephalopathy.

    Science.gov (United States)

    Hwang, Soyoun; Greenlee, Justin J; Nicholson, Eric M

    2017-01-01

    Prions are amyloid-forming proteins that cause transmissible spongiform encephalopathies through a process involving conversion from the normal cellular prion protein to the pathogenic misfolded conformation (PrPSc). This conversion has been used for in vitro assays including serial protein misfolding amplification and real-time quaking induced conversion (RT-QuIC). RT-QuIC can be used for the detection of prions in a variety of biological tissues from humans and animals. Extensive work has been done to demonstrate that RT-QuIC is a rapid, specific, and highly sensitive prion detection assay. RT-QuIC uses recombinant prion protein to detect minute amounts of PrPSc. RT-QuIC has been successfully used to detect PrPSc from different prion diseases with a variety of substrates including hamster, human, sheep, bank vole, bovine and chimeric forms of prion protein. However, recombinant bovine prion protein has not been used to detect transmissible mink encephalopathy (TME) or to differentiate types of bovine spongiform encephalopathy (BSE) in samples from cattle. We evaluated whether PrPSc from TME and BSE infected cattle can be detected with RT-QuIC using recombinant bovine prion proteins, and optimized the reaction conditions to specifically detect cattle TME and to discriminate between classical and atypical BSE by conversion efficiency. We also found that substrate composed of the disease associated E211K mutant protein can be effective for the detection of TME in cattle and that wild type prion protein appears to be a practical substrate to discriminate between the different types of BSEs.

  18. Prion protein induced signaling cascades in monocytes

    International Nuclear Information System (INIS)

    Krebs, Bjarne; Dorner-Ciossek, Cornelia; Schmalzbauer, Ruediger; Vassallo, Neville; Herms, Jochen; Kretzschmar, Hans A.

    2006-01-01

    Prion proteins play a central role in transmission and pathogenesis of transmissible spongiform encephalopathies. The cellular prion protein (PrP C ), whose physiological function remains elusive, is anchored to the surface of a variety of cell types including neurons and cells of the lymphoreticular system. In this study, we investigated the response of a mouse monocyte/macrophage cell line to exposure with PrP C fusion proteins synthesized with a human Fc-tag. PrP C fusion proteins showed an attachment to the surface of monocyte/macrophages in nanomolar concentrations. This was accompanied by an increase of cellular tyrosine phosphorylation as a result of activated signaling pathways. Detailed investigations exhibited activation of downstream pathways through a stimulation with PrP fusion proteins, which include phosphorylation of ERK 1,2 and Akt kinase. Macrophages opsonize and present antigenic structures, contact lymphocytes, and deliver cytokines. The findings reported here may become the basis of understanding the molecular function of PrP C in monocytes and macrophages

  19. Alkaloidal glycosidase inhibitors (AGIs) as the cause of sporadic scrapie, and the potential treatment of both transmissible spongiform encephalopathies (TSEs) and human immunodeficiency virus (HIV) infection.

    Science.gov (United States)

    Dealler, S

    1994-02-01

    AGIs are produced by plants and microorgansims in the environment. They are absorbed from the gut, distributed throughout the body and are concentrated inside cells. AGIs alter the glycan chains of cellular glycoproteins (CGP) during their formation so that the same CGP produced by different clones of cells (and hence with different glycan chains) becomes structurally the same. Prion protein (PrP), a CGP, is rendered indestructable to cellular mechanisms (as PrPi) by the TSE infective process; it is suggested that AGIs could both cause and prevent this by altering the primary structure of PrP. HIV envelope protein, gp120, carries glycan chains that are decided by the clone of the cells by which it is produced. Each cellular clone would be expected to add a specific group of glycan chains, making the gp120 antigenically separate. As HIV infection progresses, infected clone numbers rise, the antigenic diversity of gp120 may rise as would antibody production, trying to keep pace. Antigenically stimulated CD4+ cells carrying HIV genes, increase HIV production with gp120 antigenically different from its stimulant. AGIs prevent the glycan diversity and may prevent the extension of HIV infection.

  20. The complexity and implications of yeast prion domains

    Science.gov (United States)

    2011-01-01

    Prions are infectious proteins with altered conformations converted from otherwise normal host proteins. While there is only one known mammalian prion protein, PrP, a handful of prion proteins have been identified in the yeast Saccharomyces cerevisiae. Yeast prion proteins usually have a defined region called prion domain (PrD) essential for prion properties, which are typically rich in glutamine (Q) and asparagine (N). Despite sharing several common features, individual yeast PrDs are generally intricate and divergent in their compositional characteristics, which potentially implicates their prion phenotypes, such as prion-mediated transcriptional regulations. PMID:22156731

  1. An insight into the complex prion-prion interaction network in the budding yeast Saccharomyces cerevisiae.

    Science.gov (United States)

    Du, Zhiqiang; Valtierra, Stephanie; Li, Liming

    2014-01-01

    The budding yeast Saccharomyces cerevisiae is a valuable model system for studying prion-prion interactions as it contains multiple prion proteins. A recent study from our laboratory showed that the existence of Swi1 prion ([SWI(+)]) and overproduction of Swi1 can have strong impacts on the formation of 2 other extensively studied yeast prions, [PSI(+)] and [PIN(+)] ([RNQ(+)]) (Genetics, Vol. 197, 685-700). We showed that a single yeast cell is capable of harboring at least 3 heterologous prion elements and these prions can influence each other's appearance positively and/or negatively. We also showed that during the de novo [PSI(+)] formation process upon Sup35 overproduction, the aggregation patterns of a preexisting inducer ([RNQ(+)] or [SWI(+)]) can undergo significant remodeling from stably transmitted dot-shaped aggregates to aggregates that co-localize with the newly formed Sup35 aggregates that are ring/ribbon/rod- shaped. Such co-localization disappears once the newly formed [PSI(+)] prion stabilizes. Our finding provides strong evidence supporting the "cross-seeding" model for prion-prion interactions and confirms earlier reports that the interactions among different prions and their prion proteins mostly occur at the initiation stages of prionogenesis. Our results also highlight a complex prion interaction network in yeast. We believe that elucidating the mechanism underlying the yeast prion-prion interaction network will not only provide insight into the process of prion de novo generation and propagation in yeast but also shed light on the mechanisms that govern protein misfolding, aggregation, and amyloidogenesis in higher eukaryotes.

  2. Sod1 deficiency reduces incubation time in mouse models of prion disease.

    Directory of Open Access Journals (Sweden)

    Shaheen Akhtar

    Full Text Available Prion infections, causing neurodegenerative conditions such as Creutzfeldt-Jakob disease and kuru in humans, scrapie in sheep and BSE in cattle are characterised by prolonged and variable incubation periods that are faithfully reproduced in mouse models. Incubation time is partly determined by genetic factors including polymorphisms in the prion protein gene. Quantitative trait loci studies in mice and human genome-wide association studies have confirmed that multiple genes are involved. Candidate gene approaches have also been used and identified App, Il1-r1 and Sod1 as affecting incubation times. In this study we looked for an association between App, Il1-r1 and Sod1 representative SNPs and prion disease incubation time in the Northport heterogeneous stock of mice inoculated with the Chandler/RML prion strain. No association was seen with App, however, significant associations were seen with Il1-r1 (P = 0.02 and Sod1 (P<0.0001 suggesting that polymorphisms at these loci contribute to the natural variation observed in incubation time. Furthermore, following challenge with Chandler/RML, ME7 and MRC2 prion strains, Sod1 deficient mice showed highly significant reductions in incubation time of 20, 13 and 24%, respectively. No differences were detected in Sod1 expression or activity. Our data confirm the protective role of endogenous Sod1 in prion disease.

  3. The diagnostic efficiency of biomarkers in sporadic Creutzfeldt-Jakob disease compared to Alzheimer's disease

    DEFF Research Database (Denmark)

    Bahl, Justyna Maria Czarna; Heegaard, Niels Henrik Helweg; Falkenhorst, Gerhard

    2009-01-01

    ) together with the prion protein gene genotype to discriminate patients with sCJD (n=21) from neurological controls (n=164) and Alzheimer's disease (AD) patients (n=49). Low p-tau/t-tau ratio was the best single marker for sCJD with 90% specificity against neurological controls at 86% sensitivity whilst NSE......Laboratory markers have a prominent place among the diagnostic criteria for sporadic Creutzfeldt-Jakob disease (sCJD). Here we investigate the capability of protein 14-3-3, total-tau (t-tau), threonin-181-phosphorylated tau (p-tau), and neuron-specific enolase (NSE) in cerebrospinal fluid (CSF...

  4. Prions: the danger of biochemical weapons

    Directory of Open Access Journals (Sweden)

    Eric Almeida Xavier

    2014-09-01

    Full Text Available The knowledge of biotechnology increases the risk of using biochemical weapons for mass destruction. Prions are unprecedented infectious pathogens that cause a group of fatal neurodegenerative diseases by a novel mechanism. They are transmissible particles that are devoid of nucleic acid. Due to their singular characteristics, Prions emerge as potential danger since they can be used in the development of such weapons. Prions cause fatal infectious diseases, and to date there is no therapeutic or prophylactic approach against these diseases. Furthermore, Prions are resistant to food-preparation treatments such as high heat and can find their way from the digestive system into the nervous system; recombinant Prions are infectious either bound to soil particles or in aerosols. Therefore, lethal Prions can be developed by malicious researchers who could use it to attack political enemies since such weapons cause diseases that could be above suspicion.

  5. Lichens: Unexpected anti-prion agents?

    Science.gov (United States)

    Rodriguez, Cynthia M.; Bennett, James P.; Johnson, Christopher J.

    2012-01-01

    The prion diseases sheep scrapie and cervid chronic wasting disease are transmitted, in part, via an environmental reservoir of infectivity; prions released from infected animals persist in the environment and can cause disease years later. Central to controlling disease transmission is the identification of methods capable of inactivating these agents on the landscape. We have found that certain lichens, common, ubiquitous, symbiotic organisms, possess a serine protease capable of degrading prion protein (PrP) from prion-infected animals. The protease functions against a range of prion strains from various hosts and reduces levels of abnormal PrP by at least two logs. We have now tested more than 20 lichen species from several geographical locations and from various taxa and found that approximately half of these species degrade PrP. Critical next steps include examining the effect of lichens on prion infectivity and cloning the protease responsible for PrP degradation. The impact of lichens on prions in the environment remains unknown. We speculate that lichens could have the potential to degrade prions when they are shed from infected animals onto lichens or into environments where lichens are abundant. In addition, lichens are frequently consumed by cervids and many other animals and the effect of dietary lichens on prion disease transmission should also be considered.

  6. Nanomedicine for prion disease treatment: new insights into the role of dendrimers.

    Science.gov (United States)

    McCarthy, James M; Appelhans, Dietmar; Tatzelt, Jörg; Rogers, Mark S

    2013-01-01

    Despite their devastating impact, no effective therapeutic yet exists for prion diseases at the symptomatic stage in humans or animals. Progress is hampered by the difficulty in identifying compounds that affect PrP (Sc) and the necessity of any potential therapeutic to gain access to the CNS. Synthetic polymers known as dendrimers are a particularly promising candidate in this area. Studies with cell culture models of prion disease and prion infected brain homogenate have demonstrated that numerous species of dendrimers eliminate PrP (Sc) in a dose and time dependent fashion and specific glycodendrimers are capable of crossing the CNS. However, despite their potential a number of important questions remained unanswered such as what makes an effective dendrimer and how dendrimers eliminate prions intracellularly. In a number of recent studies we have tackled these questions and revealed for the first time that a specific dendrimer can inhibit the intracellular conversion of PrP (C) to PrP (Sc) and that a high density of surface reactive groups is a necessity for dendrimers in vitro anti-prion activity. Understanding how a therapeutic works is a vital component in maximising its activity and these studies therefore represent a significant development in the race to find effective treatments for prion diseases.

  7. Distinct prion-like strains of amyloid beta implicated in phenotypic diversity of Alzheimer's disease.

    Science.gov (United States)

    Cohen, Mark; Appleby, Brian; Safar, Jiri G

    2016-01-01

    Vast evidence on human prions demonstrates that variable disease phenotypes, rates of propagation, and targeting of distinct brain structures are determined by unique conformers (strains) of pathogenic prion protein (PrP(Sc)). Recent progress in the development of advanced biophysical tools that inventory structural characteristics of amyloid beta (Aβ) in the brain cortex of phenotypically diverse Alzheimer's disease (AD) patients, revealed unique spectrum of oligomeric particles in the cortex of rapidly progressive cases, implicating these structures in variable rates of propagation in the brain, and in distict disease manifestation. Since only ∼30% of phenotypic diversity of AD can be explained by polymorphisms in risk genes, these and transgenic bioassay data argue that structurally distinct Aβ particles play a major role in the diverse pathogenesis of AD, and may behave as distinct prion-like strains encoding diverse phenotypes. From these observations and our growing understanding of prions, there is a critical need for new strain-specific diagnostic strategies for misfolded proteins causing these elusive disorders. Since targeted drug therapy can induce mutation and evolution of prions into new strains, effective treatments of AD will require drugs that enhance clearance of pathogenic conformers, reduce the precursor protein, or inhibit the conversion of precursors into prion-like states.

  8. The Structural Architecture of an Infectious Mammalian Prion Using Electron Cryomicroscopy.

    Directory of Open Access Journals (Sweden)

    Ester Vázquez-Fernández

    2016-09-01

    Full Text Available The structure of the infectious prion protein (PrPSc, which is responsible for Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy, has escaped all attempts at elucidation due to its insolubility and propensity to aggregate. PrPSc replicates by converting the non-infectious, cellular prion protein (PrPC into the misfolded, infectious conformer through an unknown mechanism. PrPSc and its N-terminally truncated variant, PrP 27-30, aggregate into amorphous aggregates, 2D crystals, and amyloid fibrils. The structure of these infectious conformers is essential to understanding prion replication and the development of structure-based therapeutic interventions. Here we used the repetitive organization inherent to GPI-anchorless PrP 27-30 amyloid fibrils to analyze their structure via electron cryomicroscopy. Fourier-transform analyses of averaged fibril segments indicate a repeating unit of 19.1 Å. 3D reconstructions of these fibrils revealed two distinct protofilaments, and, together with a molecular volume of 18,990 Å3, predicted the height of each PrP 27-30 molecule as ~17.7 Å. Together, the data indicate a four-rung β-solenoid structure as a key feature for the architecture of infectious mammalian prions. Furthermore, they allow to formulate a molecular mechanism for the replication of prions. Knowledge of the prion structure will provide important insights into the self-propagation mechanisms of protein misfolding.

  9. Racial and ethnic differences in individuals with sporadic Creutzfeldt-jakob disease in the United States of America.

    Directory of Open Access Journals (Sweden)

    Brian S Appleby

    Full Text Available BACKGROUND: Little is known about racial and ethnic differences in individuals with sporadic Creutzfeldt-Jakob disease (sCJD. The authors sought to examine potential clinical, diagnostic, genetic, and neuropathological differences in sCJD patients of different races/ethnicities. METHODOLOGY/PRINCIPAL FINDINGS: A retrospective study of 116 definite and probable sCJD cases from Johns Hopkins and the Department of Veterans Affairs Healthcare Systems was conducted that examined differences in demographic, clinical, diagnostic, genetic, and neuropathological characteristics among racial/ethnic groups. Age at disease onset differed among racial/ethnic groups. Non-Hispanic Whites had a significantly older age at disease onset compared to the other groups (65 vs. 60, p = 0.036. Non-Whites were accurately diagnosed more rapidly than Whites (p = 0.008 and non-Hispanic Whites were more likely to have normal appearing basal ganglia on brain magnetic resonance imaging (MRI compared to minorities (p = 0.02. Whites were also more likely to undergo post-mortem evaluation compared to non-Whites (p = 0.02. CONCLUSIONS/SIGNIFICANCE: Racial/ethnic groups affected by sCJD demonstrated differences in age at disease onset, time to correct diagnosis, clinical presentation, and diagnostic test results. Whites were more likely to undergo autopsy compared to non-Whites. These results have implications in regards to case ascertainment, diagnosis, and surveillance of sCJD and possibly other human prion diseases.

  10. Prion search and cellular prion protein expression in stranded dolphins.

    Science.gov (United States)

    Di Guardo, G; Cocumelli, C; Meoli, R; Barbaro, K; Terracciano, G; Di Francesco, C E; Mazzariol, S; Eleni, C

    2012-01-01

    The recent description of a prion disease (PD) case in a free-ranging bottlenose dolphin (Tursiops truncatus) prompted us to carry out an extensive search for the disease-associated isoform (PrPSc) of the cellular prion protein (PrPC) in the brain and in a range of lymphoid tissues from 23 striped dolphins (Stenella coeruleoalba), 5 bottlenose dolphins and 2 Risso s dolphins (Grampus griseus) found stranded between 2007 and 2012 along the Italian coastline. Three striped dolphins and one bottlenose dolphin showed microscopic lesions of encephalitis, with no evidence of spongiform brain lesions being detected in any of the 30 free-ranging cetaceans investigated herein. Nevertheless, we could still observe a prominent PrPC immunoreactivity in the brain as well as in lymphoid tissues from these dolphins. Although immunohistochemical and Western blot investigations yielded negative results for PrPSc deposition in all tissues from the dolphins under study, the reported occurrence of a spontaneous PD case in a wild dolphin is an intriguing issue and a matter of concern for both prion biology and intra/inter-species transmissibility, as well as for cetacean conservation medicine.

  11. Accelerated high fidelity prion amplification within and across prion species barriers.

    Directory of Open Access Journals (Sweden)

    Kristi M Green

    2008-08-01

    Full Text Available Experimental obstacles have impeded our ability to study prion transmission within and, more particularly, between species. Here, we used cervid prion protein expressed in brain extracts of transgenic mice, referred to as Tg(CerPrP, as a substrate for in vitro generation of chronic wasting disease (CWD prions by protein misfolding cyclic amplification (PMCA. Characterization of this infectivity in Tg(CerPrP mice demonstrated that serial PMCA resulted in the high fidelity amplification of CWD prions with apparently unaltered properties. Using similar methods to amplify mouse RML prions and characterize the resulting novel cervid prions, we show that serial PMCA abrogated a transmission barrier that required several hundred days of adaptation and subsequent stabilization in Tg(CerPrP mice. While both approaches produced cervid prions with characteristics distinct from CWD, the subtly different properties of the resulting individual prion isolates indicated that adaptation of mouse RML prions generated multiple strains following inter-species transmission. Our studies demonstrate that combined transgenic mouse and PMCA approaches not only expedite intra- and inter-species prion transmission, but also provide a facile means of generating and characterizing novel prion strains.

  12. Neurotoxic Antibodies against the Prion Protein Do Not Trigger Prion Replication.

    Directory of Open Access Journals (Sweden)

    Karl Frontzek

    Full Text Available Prions are the infectious agents causing transmissible spongiform encephalopathies (TSE, progressive, inexorably lethal neurological diseases. Antibodies targeting the globular domain (GD of the cellular prion protein PrPC trigger a neurotoxic syndrome morphologically and molecularly similar to prion disease. This phenomenon raises the question whether such antibodies induce infectious prions de novo. Here we exposed cerebellar organotypic cultured slices (COCS to the neurotoxic antibody, POM1. We then inoculated COCS homogenates into tga20 mice, which overexpress PrPC and are commonly utilized as sensitive indicators of prion infectivity. None of the mice inoculated with COCS-derived lysates developed any signs of disease, and all mice survived for at least 200 days post-inoculation. In contrast, all mice inoculated with bona fide prions succumbed to TSE after 55-95 days. Post-mortem analyses did not reveal any signs of prion pathology in mice inoculated with POM1-COCS lysates. Also, lysates from POM1-exposed COCS were unable to convert PrP by quaking. Hence, anti-GD antibodies do not catalyze the generation of prion infectivity. These data indicate that prion replication can be separated from prion toxicity, and suggest that anti-GD antibodies exert toxicity by acting downstream of prion replication.

  13. PrP P102L and Nearby Lysine Mutations Promote Spontaneous In Vitro Formation of Transmissible Prions.

    Science.gov (United States)

    Kraus, Allison; Raymond, Gregory J; Race, Brent; Campbell, Katrina J; Hughson, Andrew G; Anson, Kelsie J; Raymond, Lynne D; Caughey, Byron

    2017-11-01

    Accumulation of fibrillar protein aggregates is a hallmark of many diseases. While numerous proteins form fibrils by prion-like seeded polymerization in vitro , only some are transmissible and pathogenic in vivo To probe the structural features that confer transmissibility to prion protein (PrP) fibrils, we have analyzed synthetic PrP amyloids with or without the human prion disease-associated P102L mutation. The formation of infectious prions from PrP molecules in vitro has required cofactors and/or unphysiological denaturing conditions. Here, we demonstrate that, under physiologically compatible conditions without cofactors, the P102L mutation in recombinant hamster PrP promoted prion formation when seeded by minute amounts of scrapie prions in vitro Surprisingly, combination of the P102L mutation with charge-neutralizing substitutions of four nearby lysines promoted spontaneous prion formation. When inoculated into hamsters, both of these types of synthetic prions initiated substantial accumulation of prion seeding activity and protease-resistant PrP without transmissible spongiform encephalopathy (TSE) clinical signs or notable glial activation. Our evidence suggests that PrP's centrally located proline and lysine residues act as conformational switches in the in vitro formation of transmissible PrP amyloids. IMPORTANCE Many diseases involve the damaging accumulation of specific misfolded proteins in thread-like aggregates. These threads (fibrils) are capable of growing on the ends by seeding the refolding and incorporation of the normal form of the given protein. In many cases such aggregates can be infectious and propagate like prions when transmitted from one individual host to another. Some transmitted aggregates can cause fatal disease, as with human iatrogenic prion diseases, while other aggregates appear to be relatively innocuous. The factors that distinguish infectious and pathogenic protein aggregates from more innocuous ones are poorly understood

  14. Distinct pathological phenotypes of Creutzfeldt-Jakob disease in recipients of prion-contaminated growth hormone.

    Science.gov (United States)

    Cali, Ignazio; Miller, Cathleen J; Parisi, Joseph E; Geschwind, Michael D; Gambetti, Pierluigi; Schonberger, Lawrence B

    2015-06-25

    The present study compares the clinical, pathological and molecular features of a United States (US) case of growth hormone (GH)-associated Creutzfeldt-Jakob disease (GH-CJD) (index case) to those of two earlier referred US cases of GH-CJD and one case of dura mater (d)-associated CJD (dCJD). All iatrogenic CJD (iCJD) subjects were methionine (M) homozygous at codon 129 (129MM) of the prion protein (PrP) gene and had scrapie prion protein (PrP(Sc)) type 1 (iCJDMM1). The index subject presented with ataxia, weight loss and changes in the sleep pattern about 38 years after the midpoint of GH treatment. Autopsy examination revealed a neuropathological phenotype reminiscent of both sCJDMV2-K (a sporadic CJD subtype in subjects methionine/valine heterozygous at codon 129 with PrP(Sc) type 2 and the presence of kuru plaques) and variant CJD (vCJD). The two earlier cases of GH-CJDMM1 and the one of dCJDMM1 were associated with neuropathological phenotypes that differed from that of the index case mainly because they lacked PrP plaques. The phenotype of the earlier GH-CJDMM1 cases shared several, but not all, characteristics with sCJDMM1, whereas dCJDMM1 was phenotypically indistinguishable from sCJDMM1. Two distinct groups of dCJDMM1 have also been described in Japan based on clinical features, the presence or absence of PrP plaques and distinct PK-resistant PrP(Sc) (resPrP(Sc)) electrophoretic mobilities. The resPrP(Sc) electrophoretic mobility was, however, identical in our GH-CJDMM1 and dCJDMM1 cases, and matched that of sCJDMM1. Our study shows that receipt of prion-contaminated GH can lead to a prion disease with molecular features (129MM and PrP(Sc) type 2) and phenotypic characteristics that differ from those of sporadic prion disease (sCJDMM1), a difference that may reflect adaptation of "heterologous" prion strains to the 129MM background.

  15. Localization of A11-reactive oligomeric species in prion diseases

    DEFF Research Database (Denmark)

    Aidt, Frederik H; Hasholt, Lis F; Christiansen, Michael

    2013-01-01

    To investigate in prion diseases the in-situ localization of prion protein oligomers sharing a common epitope with amyloid oligomers involved in a range of neurodegenerative diseases.......To investigate in prion diseases the in-situ localization of prion protein oligomers sharing a common epitope with amyloid oligomers involved in a range of neurodegenerative diseases....

  16. Direct Detection of Soil-Bound Prions

    Science.gov (United States)

    Genovesi, Sacha; Leita, Liviana; Sequi, Paolo; Andrighetto, Igino; Sorgato, M. Catia; Bertoli, Alessandro

    2007-01-01

    Scrapie and chronic wasting disease are contagious prion diseases affecting sheep and cervids, respectively. Studies have indicated that horizontal transmission is important in sustaining these epidemics, and that environmental contamination plays an important role in this. In the perspective of detecting prions in soil samples from the field by more direct methods than animal-based bioassays, we have developed a novel immuno-based approach that visualises in situ the major component (PrPSc) of prions sorbed onto agricultural soil particles. Importantly, the protocol needs no extraction of the protein from soil. Using a cell-based assay of infectivity, we also report that samples of agricultural soil, or quartz sand, acquire prion infectivity after exposure to whole brain homogenates from prion-infected mice. Our data provide further support to the notion that prion-exposed soils retain infectivity, as recently determined in Syrian hamsters intracerebrally or orally challanged with contaminated soils. The cell approach of the potential infectivity of contaminated soil is faster and cheaper than classical animal-based bioassays. Although it suffers from limitations, e.g. it can currently test only a few mouse prion strains, the cell model can nevertheless be applied in its present form to understand how soil composition influences infectivity, and to test prion-inactivating procedures. PMID:17957252

  17. Direct detection of soil-bound prions.

    Directory of Open Access Journals (Sweden)

    Sacha Genovesi

    Full Text Available Scrapie and chronic wasting disease are contagious prion diseases affecting sheep and cervids, respectively. Studies have indicated that horizontal transmission is important in sustaining these epidemics, and that environmental contamination plays an important role in this. In the perspective of detecting prions in soil samples from the field by more direct methods than animal-based bioassays, we have developed a novel immuno-based approach that visualises in situ the major component (PrP(Sc of prions sorbed onto agricultural soil particles. Importantly, the protocol needs no extraction of the protein from soil. Using a cell-based assay of infectivity, we also report that samples of agricultural soil, or quartz sand, acquire prion infectivity after exposure to whole brain homogenates from prion-infected mice. Our data provide further support to the notion that prion-exposed soils retain infectivity, as recently determined in Syrian hamsters intracerebrally or orally challenged with contaminated soils. The cell approach of the potential infectivity of contaminated soil is faster and cheaper than classical animal-based bioassays. Although it suffers from limitations, e.g. it can currently test only a few mouse prion strains, the cell model can nevertheless be applied in its present form to understand how soil composition influences infectivity, and to test prion-inactivating procedures.

  18. Medical Procedures and Risk for Sporadic Creutzfeldt-Jakob Disease, Japan, 1999–2008

    Science.gov (United States)

    Hamaguchi, Tsuyoshi; Noguchi-Shinohara, Moeko; Nozaki, Ichiro; Nakamura, Yosikazu; Sato, Takeshi; Kitamoto, Tetsuyuki; Mizusawa, Hidehiro

    2009-01-01

    To elucidate the association between medical procedures and sporadic Creutzfeldt-Jakob disease (sCJD), we analyzed medical procedures (any surgical procedure, neurosurgery, ophthalmic surgery, and blood transfusion) for patients registered by the CJD Surveillance Committee in Japan during 1999–2008. We conducted an age-stratified case–control study with 753 sCJD patients and 210 controls and a study of patients who underwent neurosurgical or ophthalmic surgical procedures at the same hospital. Although the control group was relatively small, no evidence was found that prion disease was transmitted through the investigated medical procedures before onset of sCJD. After onset of sCJD, 4.5% of the sCJD patients underwent operations, including neurosurgical for 0.8% and ophthalmic for 1.9%; no special precautions against transmission of prion diseases were taken. Fortunately, we have not identified patients with prion disease attributed to these operations. Our findings indicate that surgical procedures or blood transfusion had little effect on the incidence of sCJD. PMID:19193271

  19. Laminar Distribution of the Pathological Changes in Sporadic and Variant Creutzfeldt-Jakob Disease

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    R. A. Armstrong

    2011-01-01

    Full Text Available The laminar distributions of the pathological changes in the cerebral cortex were compared in the prion diseases sporadic Creutzfeldt-Jakob disease (sCJD and variant CJD (vCJD. First, in some cortical regions, the vacuolation (“spongiform change” was more generally distributed across the cortex in sCJD. Second, there was greater neuronal loss in the upper cortex in vCJD and in the lower cortex in sCJD. Third, the “diffuse” and “florid” prion protein (PrPsc deposits were more frequently distributed in the upper cortex in vCJD and the “synaptic” deposits in the lower cortex in sCJD. Fourth, there was a significant gliosis mainly affecting the lower cortex of both disorders. The data suggest that the pattern of cortical degeneration is different in sCJD and vCJD which may reflect differences in aetiology and the subsequent spread of prion pathology within the brain.

  20. Neuropsychological Symptoms in Sporadic Creutzfeldt-Jakob Disease Patients in Germany.

    Science.gov (United States)

    Krasnianski, Anna; Bohling, Geeske T; Heinemann, Uta; Varges, Daniela; Meissner, Bettina; Schulz-Schaeffer, Walter J; Reif, Andreas; Zerr, Inga

    2017-01-01

    The polymorphism at codon 129 of the prion protein gene (PRNP) and the PrPSc types 1 and 2 belong to a molecular classification of sporadic Creutzfeldt-Jakob disease (sCJD) that correlates well with the clinical and neuropathological phenotype of sCJD. The aim of the study was to perform the first detailed evaluation of neuropsychological deficits in a large group of definite sCJD patients with known molecular subtype. We analyzed neuropsychological symptoms in a cohort of 248 sCJD patients with known M129 V polymorphism of PRNP and prion protein type. Neuropsychological symptoms were very frequent in our patients (96%) and occurred as early as in the first third of the disease course. Besides amnesia and impaired attention (89% each), frontal lobe syndrome (75%), aphasia (63%), and apraxia (57%) were the most common neuropsychological deficits. There was no statistically significant difference with regard to frequency of neuropsychological symptoms between the subtypes. In MV2 and VV2 patients, the onset of neuropsychological symptoms was significantly later than in all other subtypes. We provide the first detailed analysis of neuropsychological symptoms in a large group of sCJD patients with known M129 V genotype and prion protein type. We suggest that the rate of progression of neuropsychological symptoms is subtype-specific. These data may improve the diagnosis in atypical sCJD subtypes.

  1. Positive selection at codon 38 of the human KCNE1 (= minK gene and sporadic absence of 38Ser-coding mRNAs in Gly38Ser heterozygotes

    Directory of Open Access Journals (Sweden)

    Pfeufer Arne

    2009-08-01

    Full Text Available Abstract Background KCNE1 represents the regulatory beta-subunit of the slowly activating delayed rectifier potassium channel (IKs. Variants of KCNE1 have repeatedly been linked to the long-QT syndrome (LQTS, a disorder which predisposes to deafness, ventricular tachyarrhythmia, syncope, and sudden cardiac death. Results We here analyze the evolution of the common Gly38Ser variant (rs1805127, using genomic DNAs, complementary DNAs, and HEK293-expressed variants of altogether 19 mammalian species. The between species comparison reveals that the human-specific Gly38Ser polymorphism evolved under strong positive Darwinian selection, probably in adaptation to specific challenges in the fine-tuning of IKs channels. The involved amino acid exchanges (Asp > Gly, Gly > Ser are moderately radical and do not induce apparent changes in posttranslational modification. According to population genetic analyses (HapMap phase II a heterozygote advantage accounts for the maintenance of the Gly38Ser polymorphism in humans. On the other hand, the expression of the 38Ser allele seems to be disadvantageous under certain conditions, as suggested by the sporadic deficiency of 38Ser-coding mRNAs in heterozygote Central Europeans and the depletion of homozygotes 38Ser in the Yoruban sample. Conclusion We speculate that individual differences in genomic imprinting or genomic recoding might have contributed to conflicting results of recent association studies between Gly38Ser polymorphism and QT phenotype. The findings thus highlight the relevance of mRNA data in future association studies of genotypes and clinical disorders. To the best of our knowledge, they moreover provide first time evidence for a unique pattern; i.e. coincidence of positive Darwinian selection and polymorphism with a sporadically suppressed expression of one allele.

  2. Covalent surface modification of prions: a mass spectrometry-based means of detecting distinctive structural features of prion strains

    Science.gov (United States)

    Prions (PrPSc) are molecular pathogens that are able to convert the isosequential normal cellular prion protein (PrPC) into a prion. The only demonstrated differences between PrPC and PrPSc is conformational, they are isoforms. A given host can be infected by more than one kind or strain of prion. F...

  3. Neuroendocrine Differentiation in Sporadic CRC and Hereditary Nonpolyosis Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    M. H. Sun

    2004-01-01

    Full Text Available Extent neuroendocrine differentiation can be encountered in many human neoplasm derived from different organs and systems using immunohistochemistry and ultrastructural techniques. The tumor cells' behaviors resemble those of neurons and neuroendocrine cells. The presence of neuroendocrine differentiation reputedly appears to be associated with a poorer prognosis than the adenocarcinoma counterparts in sporadic human neoplasm. In this review the neuroendocrine carcinoma and the adenocarcinoma with neuroendocrine differentiation of colon and rectum both in sporadic colorectal carcinoma and the hereditary nonpolyposis colorectal cancer, the relationship of neuroendocrine differentiation and some possible molecular pathways in tumorogenesis of colorectal cancer will be discussed. Possible treatment strategy will also be addressed.

  4. Prion replication without host adaptation during interspecies transmissions.

    Science.gov (United States)

    Bian, Jifeng; Khaychuk, Vadim; Angers, Rachel C; Fernández-Borges, Natalia; Vidal, Enric; Meyerett-Reid, Crystal; Kim, Sehun; Calvi, Carla L; Bartz, Jason C; Hoover, Edward A; Agrimi, Umberto; Richt, Jürgen A; Castilla, Joaquín; Telling, Glenn C

    2017-01-31

    Adaptation of prions to new species is thought to reflect the capacity of the host-encoded cellular form of the prion protein (PrP C ) to selectively propagate optimized prion conformations from larger ensembles generated in the species of origin. Here we describe an alternate replicative process, termed nonadaptive prion amplification (NAPA), in which dominant conformers bypass this requirement during particular interspecies transmissions. To model susceptibility of horses to prions, we produced transgenic (Tg) mice expressing cognate PrP C Although disease transmission to only a subset of infected TgEq indicated a significant barrier to EqPrP C conversion, the resulting horse prions unexpectedly failed to cause disease upon further passage to TgEq. TgD expressing deer PrP C was similarly refractory to deer prions from diseased TgD infected with mink prions. In both cases, the resulting prions transmitted to mice expressing PrP C from the species of prion origin, demonstrating that transmission barrier eradication of the originating prions was ephemeral and adaptation superficial in TgEq and TgD. Horse prions produced in vitro by protein misfolding cyclic amplification of mouse prions using horse PrP C also failed to infect TgEq but retained tropism for wild-type mice. Concordant patterns of neuropathology and prion deposition in susceptible mice infected with NAPA prions and the corresponding prion of origin confirmed preservation of strain properties. The comparable responses of both prion types to guanidine hydrochloride denaturation indicated this occurs because NAPA precludes selection of novel prion conformations. Our findings provide insights into mechanisms regulating interspecies prion transmission and a framework to reconcile puzzling epidemiological features of certain prion disorders.

  5. Interaction of human laminin receptor with Sup35, the [PSI⁺] prion-forming protein from S. cerevisiae: a yeast model for studies of LamR interactions with amyloidogenic proteins.

    Directory of Open Access Journals (Sweden)

    Christine Pampeno

    Full Text Available The laminin receptor (LamR is a cell surface receptor for extracellular matrix laminin, whereas the same protein within the cell interacts with ribosomes, nuclear proteins and cytoskeletal fibers. LamR has been shown to be a receptor for several bacteria and viruses. Furthermore, LamR interacts with both cellular and infectious forms of the prion protein, PrP(C and PrP(Sc. Indeed, LamR is a receptor for PrP(C. Whether LamR interacts with PrP(Sc exclusively in a capacity of the PrP receptor, or LamR specifically recognizes prion determinants of PrP(Sc, is unclear. In order to explore whether LamR has a propensity to interact with prions and amyloids, we examined LamR interaction with the yeast prion-forming protein, Sup35. Sup35 is a translation termination factor with no homology or functional relationship to PrP. Plasmids expressing LamR or LamR fused with the green fluorescent protein (GFP were transformed into yeast strain variants differing by the presence or absence of the prion conformation of Sup35, respectively [PSI⁺] and [psi⁻]. Analyses by immunoprecipitation, centrifugal fractionation and fluorescent microscopy reveal interaction between LamR and Sup35 in [PSI⁺] strains. The presence of [PSI⁺] promotes LamR co-precipitation with Sup35 as well as LamR aggregation. In [PSI⁺] cells, LamR tagged with GFP or mCherry forms bright fluorescent aggregates that co-localize with visible [PSI⁺] foci. The yeast prion model will facilitate studying the interaction of LamR with amyloidogenic prions in a safe and easily manipulated system that may lead to a better understanding and treatment of amyloid diseases.

  6. Prion protein immunocytochemistry helps to establish the true incidence of prion diseases.

    Science.gov (United States)

    Lantos, P L; McGill, I S; Janota, I; Doey, L J; Collinge, J; Bruce, M T; Whatley, S A; Anderton, B H; Clinton, J; Roberts, G W

    1992-11-23

    Creutzfeldt-Jakob disease (CJD) and Gerstmann-Strüssler-Scheinker disease (GSSD) are transmissible spongiform encephalopathies or prion diseases affecting man. It has been reported that prion diseases may occur without the histological hallmarks of spongiform encephalopathies: vacuolation of the cerebral grey matter, neuronal loss and astrocytosis. These cases without characteristic neuropathology may go undiagnosed and consequently the true incidence of transmissible dementias is likely to have been under-estimated. Immunocytochemistry using antibodies to prion protein gives positive staining of these cases, albeit the pattern of immunostaining differs from that seen in typical forms. Accumulation of prion protein is a molecular hallmark of prion diseases, and thus a reproducible, speedy and cost-efficient immunocytochemical screening of unusual dementias may help to establish the true incidence of prion diseases.

  7. In vivo detection of prion amyloid plaques using [{sup 11}C]BF-227 PET

    Energy Technology Data Exchange (ETDEWEB)

    Okamura, Nobuyuki; Yanai, Kazuhiko [Tohoku University School of Medicine, Department of Pharmacology, Sendai (Japan); Shiga, Yusei; Itoyama, Yasuhito [Tohoku University School of Medicine, Department of Neurology, Sendai (Japan); Furumoto, Shozo [Tohoku University School of Medicine, Department of Pharmacology, Sendai (Japan); Tohoku University, Division of Radiopharmaceutical Chemistry, Cyclotron and Radioisotope Center, Sendai (Japan); Tashiro, Manabu [Tohoku University, Division of Cyclotron Nuclear Medicine, Cyclotron and Radioisotope Center, Sendai (Japan); Tsuboi, Yoshio [Fukuoka University School of Medicine, Department of Neurology, Fukuoka (Japan); Furukawa, Katsutoshi; Arai, Hiroyuki [Institute of Development, Aging, and Cancer, Tohoku University, Department of Geriatrics and Gerontology, Division of Brain Sciences, Sendai (Japan); Iwata, Ren [Tohoku University, Division of Radiopharmaceutical Chemistry, Cyclotron and Radioisotope Center, Sendai (Japan); Kudo, Yukitsuka [Tohoku University, Innovation of New Biomedical Engineering Center, Sendai (Japan); Doh-ura, Katsumi [Tohoku University School of Medicine, Department of Prion Research, 2-1 Seiryo-machi, Aoba-ku, Sendai (Japan)

    2010-05-15

    In vivo detection of pathological prion protein (PrP) in the brain is potentially useful for the diagnosis of transmissible spongiform encephalopathies (TSEs). However, there are no non-invasive ante-mortem means for detection of pathological PrP deposition in the brain. The purpose of this study is to evaluate the amyloid imaging tracer BF-227 with positron emission tomography (PET) for the non-invasive detection of PrP amyloid in the brain. The binding ability of BF-227 to PrP amyloid was investigated using autoradiography and fluorescence microscopy. Five patients with TSEs, including three patients with Gerstmann-Straeussler-Scheinker disease (GSS) and two patients with sporadic Creutzfeldt-Jakob disease (CJD), underwent [{sup 11}C]BF-227 PET scans. Results were compared with data from 10 normal controls and 17 patients with Alzheimer's disease (AD). The regional to pons standardized uptake value ratio was calculated as an index of BF-227 retention. Binding of BF-227 to PrP plaques was confirmed using brain samples from autopsy-confirmed GSS cases. In clinical PET study, significantly higher retention of BF-227 was detected in the cerebellum, thalamus and lateral temporal cortex of GSS patients compared to that in the corresponding tissues of normal controls. GSS patients also showed higher retention of BF-227 in the cerebellum, thalamus and medial temporal cortex compared to AD patients. In contrast, the two CJD patients showed no obvious retention of BF-227 in the brain. Although [{sup 11}C]BF-227 is a non-specific imaging marker of cerebral amyloidosis, it is useful for in vivo detection of PrP plaques in the human brain in GSS, based on the regional distribution of the tracer. PET amyloid imaging might provide a means for both early diagnosis and non-invasive disease monitoring of certain forms of TSEs. (orig.)

  8. In vivo detection of prion amyloid plaques using [11C]BF-227 PET

    International Nuclear Information System (INIS)

    Okamura, Nobuyuki; Yanai, Kazuhiko; Shiga, Yusei; Itoyama, Yasuhito; Furumoto, Shozo; Tashiro, Manabu; Tsuboi, Yoshio; Furukawa, Katsutoshi; Arai, Hiroyuki; Iwata, Ren; Kudo, Yukitsuka; Doh-ura, Katsumi

    2010-01-01

    In vivo detection of pathological prion protein (PrP) in the brain is potentially useful for the diagnosis of transmissible spongiform encephalopathies (TSEs). However, there are no non-invasive ante-mortem means for detection of pathological PrP deposition in the brain. The purpose of this study is to evaluate the amyloid imaging tracer BF-227 with positron emission tomography (PET) for the non-invasive detection of PrP amyloid in the brain. The binding ability of BF-227 to PrP amyloid was investigated using autoradiography and fluorescence microscopy. Five patients with TSEs, including three patients with Gerstmann-Straeussler-Scheinker disease (GSS) and two patients with sporadic Creutzfeldt-Jakob disease (CJD), underwent [ 11 C]BF-227 PET scans. Results were compared with data from 10 normal controls and 17 patients with Alzheimer's disease (AD). The regional to pons standardized uptake value ratio was calculated as an index of BF-227 retention. Binding of BF-227 to PrP plaques was confirmed using brain samples from autopsy-confirmed GSS cases. In clinical PET study, significantly higher retention of BF-227 was detected in the cerebellum, thalamus and lateral temporal cortex of GSS patients compared to that in the corresponding tissues of normal controls. GSS patients also showed higher retention of BF-227 in the cerebellum, thalamus and medial temporal cortex compared to AD patients. In contrast, the two CJD patients showed no obvious retention of BF-227 in the brain. Although [ 11 C]BF-227 is a non-specific imaging marker of cerebral amyloidosis, it is useful for in vivo detection of PrP plaques in the human brain in GSS, based on the regional distribution of the tracer. PET amyloid imaging might provide a means for both early diagnosis and non-invasive disease monitoring of certain forms of TSEs. (orig.)

  9. De novo generation of infectious prions with bacterially expressed recombinant prion protein.

    Science.gov (United States)

    Zhang, Zhihong; Zhang, Yi; Wang, Fei; Wang, Xinhe; Xu, Yuanyuan; Yang, Huaiyi; Yu, Guohua; Yuan, Chonggang; Ma, Jiyan

    2013-12-01

    The prion hypothesis is strongly supported by the fact that prion infectivity and the pathogenic conformer of prion protein (PrP) are simultaneously propagated in vitro by the serial protein misfolding cyclic amplification (sPMCA). However, due to sPMCA's enormous amplification power, whether an infectious prion can be formed de novo with bacterially expressed recombinant PrP (rPrP) remains to be satisfactorily resolved. To address this question, we performed unseeded sPMCA with rPrP in a laboratory that has never been exposed to any native prions. Two types of proteinase K (PK)-resistant and self-perpetuating recombinant PrP conformers (rPrP-res) with PK-resistant cores of 17 or 14 kDa were generated. A bioassay revealed that rPrP-res(17kDa) was highly infectious, causing prion disease in wild-type mice with an average survival time of about 172 d. In contrast, rPrP-res(14kDa) completely failed to induce any disease. Our findings reveal that sPMCA is sufficient to initiate various self-perpetuating PK-resistant rPrP conformers, but not all of them possess in vivo infectivity. Moreover, generating an infectious prion in a prion-free environment establishes that an infectious prion can be formed de novo with bacterially expressed rPrP.

  10. Ex vivo mammalian prions are formed of paired double helical prion protein fibrils.

    Science.gov (United States)

    Terry, Cassandra; Wenborn, Adam; Gros, Nathalie; Sells, Jessica; Joiner, Susan; Hosszu, Laszlo L P; Tattum, M Howard; Panico, Silvia; Clare, Daniel K; Collinge, John; Saibil, Helen R; Wadsworth, Jonathan D F

    2016-05-01

    Mammalian prions are hypothesized to be fibrillar or amyloid forms of prion protein (PrP), but structures observed to date have not been definitively correlated with infectivity and the three-dimensional structure of infectious prions has remained obscure. Recently, we developed novel methods to obtain exceptionally pure preparations of prions from mouse brain and showed that pathogenic PrP in these high-titre preparations is assembled into rod-like assemblies. Here, we have used precise cell culture-based prion infectivity assays to define the physical relationship between the PrP rods and prion infectivity and have used electron tomography to define their architecture. We show that infectious PrP rods isolated from multiple prion strains have a common hierarchical assembly comprising twisted pairs of short fibres with repeating substructure. The architecture of the PrP rods provides a new structural basis for understanding prion infectivity and can explain the inability to systematically generate high-titre synthetic prions from recombinant PrP. © 2016 The Authors.

  11. Orthogonal typing methods identify genetic diversity among Belgian Campylobacter jejuni strains isolated over a decade from poultry and cases of sporadic human illness

    Science.gov (United States)

    Campylobacter jejuni is a zoonotic pathogen commonly associated with human gastroenteritis. Retail poultry meat is a major food-related transmission source of C. jejuni to humans. The present study investigated the genetic diversity, clonal relationship, and strain risk-ranking of 403 representativ...

  12. Prion Protein Regulates Iron Transport by Functioning as a Ferrireductase

    Science.gov (United States)

    Singh, Ajay; Haldar, Swati; Horback, Katharine; Tom, Cynthia; Zhou, Lan; Meyerson, Howard; Singh, Neena

    2017-01-01

    Prion protein (PrPC) is implicated in the pathogenesis of prion disorders, but its normal function is unclear. We demonstrate that PrPC is a ferrireductase (FR), and its absence causes systemic iron deficiency in PrP knock-out mice (PrP−/−). When exposed to non-transferrin-bound (NTB) radioactive-iron (59FeCl3) by gastric-gavage, PrP−/− mice absorb significantly more 59Fe from the intestinal lumen relative to controls, indicating appropriate systemic response to the iron deficiency. Chronic exposure to excess dietary iron corrects this deficiency, but unlike wild-type (PrP+/+) controls that remain iron over-loaded, PrP−/− mice revert back to the iron deficient phenotype after 5 months of chase on normal diet. Bone marrow (BM) preparations of PrP−/− mice on normal diet show relatively less stainable iron, and this phenotype is only partially corrected by intraperitoneal administration of excess iron-dextran. Cultured PrP−/− BM-macrophages incorporate significantly less NTB-59Fe in the absence or presence of excess extracellular iron, indicating reduced uptake and/or storage of available iron in the absence of PrPC. When expressed in neuroblastoma cells, PrPC exhibits NAD(P)H-dependent cell-surface and intracellular FR activity that requires the copper-binding octa-peptide-repeat region and linkage to the plasma membrane for optimal function. Incorporation of NTB-59Fe by neuroblastoma cells correlates with FR activity of PrPC, implicating PrPC in cellular iron uptake and metabolism. These observations explain the correlation between PrPC expression and cellular iron levels, and the cause of iron imbalance in sporadic-Creutzfeldt-Jakob-disease brains where PrPC accumulates as insoluble aggregates. PMID:23478311

  13. Agraphia of Kanji (Chinese characters): an early symptom of sporadic Creutzfeldt-Jakob disease in a Japanese patient: a case report.

    Science.gov (United States)

    Nakamura, Keiko; Sakai, Kenji; Samuraki, Miharu; Nozaki, Ichiro; Notoya, Masako; Yamada, Masahito

    2014-08-06

    Slowly progressive cognitive decline is the most frequent initial manifestation in MM2-cortical-type sporadic Creutzfeldt-Jakob disease. Agraphia has never been noted in patients with this type of sporadic Creutzfeldt-Jakob disease, however, we report the case of a Japanese patient with sporadic Creutzfeldt-Jakob disease in whom agraphia of Kanji was an initial cardinal symptom. A 59-year-old right-handed Japanese woman complained of agraphia of Kanji (Chinese characters) as an initial symptom. A neurological examination revealed mild word-finding difficulty, constructive disturbance, hyperreflexia in her jaw and lower limbs, and bilateral extensor plantar reflexes. An examination of her cerebrospinal fluid revealed increased levels of 14-3-3 and total tau proteins, and abnormal conformation of the proteinase K-resistant prion protein. Diffusion-weighted magnetic resonance imaging showed diffuse hyperintensity in bilateral cerebral cortices. Single-photon emission computed tomography scans revealed hypoperfusion in the left temporal lobe, bilateral parietal and occipital lobes. An analysis of the prion protein gene demonstrated no mutation with homozygous for methionine at the codon 129. We diagnosed our patient with sporadic Creutzfeldt-Jakob disease. Although a histological examination was not performed, it was assumed that our patient could be the MM2-cortical type according to the clinical findings and the elevated levels of 14-3-3 protein in her cerebrospinal fluid. The left posterior inferior temporal area, which was affected in our patient as a hypoperfusion area, is associated with selecting and recalling Kanji characters. Focal signs as an early symptom and hypoperfusion areas in sporadic Creutzfeldt-Jakob disease are critical to recognize initial brain lesions damaged by the proteinase K-resistant prion protein accumulation.

  14. Small stress molecules inhibit aggregation and neurotoxicity of prion peptide 106-126

    International Nuclear Information System (INIS)

    Kanapathipillai, Mathumai; Ku, Sook Hee; Girigoswami, Koyeli; Park, Chan Beum

    2008-01-01

    In prion diseases, the posttranslational modification of host-encoded prion protein PrP c yields a high β-sheet content modified protein PrP sc , which further polymerizes into amyloid fibrils. PrP106-126 initiates the conformational changes leading to the conversion of PrP c to PrP sc . Molecules that can defunctionalize such peptides can serve as a potential tool in combating prion diseases. In microorganisms during stressed conditions, small stress molecules (SSMs) are formed to prevent protein denaturation and maintain protein stability and function. The effect of such SSMs on PrP106-126 amyloid formation is explored in the present study using turbidity, atomic force microscopy (AFM), and cellular toxicity assay. Turbidity and AFM studies clearly depict that the SSMs-ectoine and mannosylglyceramide (MGA) inhibit the PrP106-126 aggregation. Our study also connotes that ectoine and MGA offer strong resistance to prion peptide-induced toxicity in human neuroblastoma cells, concluding that such molecules can be potential inhibitors of prion aggregation and toxicity

  15. Toward unfolding the prion misfolding mystery: protein free radical chemistry in transmissible spongiform encephalopathies

    International Nuclear Information System (INIS)

    Yang Chiming

    2003-01-01

    Owing to the high oxygen-respiration in the brain of mammals, oxidative damage to prion protein has been suggested to be an additional factor. A large body of intriguing features of scrapie and prion diseases have provided multiple lines of indirect chemistry evidence, suggesting that the infectious agents may be putative forms of sequence-specific prion radicals (SSPR) and/or their immediate precursors in the transmissible spongiform encephalopathies (TSE). Here a molecular mechanism corresponding to the self-replication of scrapie protein mediated by prion free-radical processes, consonant with 'protein-only' hypotheses is proposed. This new theory may not only aid our understanding of the occurrence of prions, but also provides new insight into the possible chemistry principles underlying the neutrodegenerative disorders. It is anticipated that future studies based on this suggestion and chemistry principles of genetic diseases may allow us to determine an effective approach to stop mad cow disease and its human version, new variant of Creutzfeldt-Jakob disease (v CJD)

  16. Biochemical features of genetic Creutzfeldt-Jakob disease with valine-to-isoleucine substitution at codon 180 on the prion protein gene.

    Science.gov (United States)

    Ito, Yoko; Sanjo, Nobuo; Hizume, Masaki; Kobayashi, Atsushi; Ohgami, Tetsuya; Satoh, Katsuya; Hamaguchi, Tsuyoshi; Yamada, Masahito; Kitamoto, Tetsuyuki; Mizusawa, Hidehiro; Yokota, Takanori

    2018-02-19

    Valine-to-isoleucine substitution at codon 180 of the prion protein gene is only observed in patients with Creutzfeldt-Jakob disease and accounts for approximately half of all cases of genetic prion disease in Japan. In the present study, we investigated the biochemical characteristics of valine-to-isoleucine substitution at codon 180 in the prion protein gene, using samples obtained from the autopsied brains of seven patients with genetic Creutzfeldt-Jakob disease exhibiting this mutation (diagnoses confirmed via neuropathological examination). Among these patients, we observed an absence of diglycosylated and monoglycosylated forms of PrP res at codon 181. Our findings further indicated that the abnormal prion proteins were composed of at least three components, although smaller carboxyl-terminal fragments were predominant. Western blot analyses revealed large amounts of PrP res in the cerebral neocortices, where neuropathological examination revealed marked spongiosis. Relatively smaller amounts of PrP res were detected in the hippocampus, where milder spongiosis was observed, than in the cerebral neocortex. These findings indicate that abnormal prion proteins in the neocortex are associated with severe toxicity, resulting in severe spongiosis. Our findings further indicate that the valine-to-isoleucine substitution is not a polymorphism, but rather an authentic pathogenic mutation associated with specific biochemical characteristics that differ from those observed in sporadic Creutzfeldt-Jakob disease. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Propagation of Mammalian Prions in Yeast

    National Research Council Canada - National Science Library

    Harris, David A

    2006-01-01

    ...: the budding yeast Saccharomyces cerevisiae. This unicellular organism offers a number of potential advantages for the study of prion biology, including rapid generation time, ease of culturing, and facile genetics...

  18. Protein Misfolding Cyclic Amplification of Infectious Prions.

    Science.gov (United States)

    Moda, Fabio

    2017-01-01

    Transmissible spongiform encephalopathies, or prion diseases, are a group of incurable disorders caused by the accumulation of an abnormally folded prion protein (PrP Sc ) in the brain. According to the "protein-only" hypothesis, PrP Sc is the infectious agent able to propagate the disease by acting as a template for the conversion of the correctly folded prion protein (PrP C ) into the pathological isoform. Recently, the mechanism of PrP C conversion has been mimicked in vitro using an innovative technique named protein misfolding cyclic amplification (PMCA). This technology represents a great tool for studying diverse aspects of prion biology in the field of basic research and diagnosis. Moreover, PMCA can be expanded for the study of the misfolding process associated to other neurodegenerative diseases, including Alzheimer's disease, Parkinson's disease, and frontotemporal lobar degeneration. © 2017 Elsevier Inc. All rights reserved.

  19. Dissociation of recombinant prion autocatalysis from infectivity.

    Science.gov (United States)

    Noble, Geoffrey P; Supattapone, Surachai

    2015-01-01

    Within the mammalian prion field, the existence of recombinant prion protein (PrP) conformers with self-replicating (ie. autocatalytic) activity in vitro but little to no infectious activity in vivo challenges a key prediction of the protein-only hypothesis of prion replication--that autocatalytic PrP conformers should be infectious. To understand this dissociation of autocatalysis from infectivity, we recently performed a structural and functional comparison between a highly infectious and non-infectious pair of autocatalytic recombinant PrP conformers derived from the same initial prion strain. (1) We identified restricted, C-terminal structural differences between these 2 conformers and provided evidence that these relatively subtle differences prevent the non-infectious conformer from templating the conversion of native PrP(C) substrates containing a glycosylphosphatidylinositol (GPI) anchor. (1) In this article we discuss a model, consistent with these findings, in which recombinant PrP, lacking post-translational modifications and associated folding constraints, is capable of adopting a wide variety of autocatalytic conformations. Only a subset of these recombinant conformers can be adopted by post-translationally modified native PrP(C), and this subset represents the recombinant conformers with high specific infectivity. We examine this model's implications for the generation of highly infectious recombinant prions and the protein-only hypothesis of prion replication.

  20. Soil clay content underlies prion infection odds

    Science.gov (United States)

    David, Walter W.; Walsh, D.P.; Farnsworth, Matthew L.; Winkelman, D.L.; Miller, M.W.

    2011-01-01

    Environmental factors-especially soil properties-have been suggested as potentially important in the transmission of infectious prion diseases. Because binding to montmorillonite (an aluminosilicate clay mineral) or clay-enriched soils had been shown to enhance experimental prion transmissibility, we hypothesized that prion transmission among mule deer might also be enhanced in ranges with relatively high soil clay content. In this study, we report apparent influences of soil clay content on the odds of prion infection in free-ranging deer. Analysis of data from prion-infected deer herds in northern Colorado, USA, revealed that a 1% increase in the clay-sized particle content in soils within the approximate home range of an individual deer increased its odds of infection by up to 8.9%. Our findings suggest that soil clay content and related environmental properties deserve greater attention in assessing risks of prion disease outbreaks and prospects for their control in both natural and production settings. ?? 2011 Macmillan Publishers Limited. All rights reserved.

  1. Fatal Prion Disease in a Mouse Model of Genetic E200K Creutzfeldt-Jakob Disease

    Science.gov (United States)

    Friedman-Levi, Yael; Meiner, Zeev; Canello, Tamar; Frid, Kati; Kovacs, Gabor G.; Budka, Herbert; Avrahami, Dana; Gabizon, Ruth

    2011-01-01

    Genetic prion diseases are late onset fatal neurodegenerative disorders linked to pathogenic mutations in the prion protein-encoding gene, PRNP. The most prevalent of these is the substitution of Glutamate for Lysine at codon 200 (E200K), causing genetic Creutzfeldt-Jakob disease (gCJD) in several clusters, including Jews of Libyan origin. Investigating the pathogenesis of genetic CJD, as well as developing prophylactic treatments for young asymptomatic carriers of this and other PrP mutations, may well depend upon the availability of appropriate animal models in which long term treatments can be evaluated for efficacy and toxicity. Here we present the first effective mouse model for E200KCJD, which expresses chimeric mouse/human (TgMHu2M) E199KPrP on both a null and a wt PrP background, as is the case for heterozygous patients and carriers. Mice from both lines suffered from distinct neurological symptoms as early as 5–6 month of age and deteriorated to death several months thereafter. Histopathological examination of the brain and spinal cord revealed early gliosis and age-related intraneuronal deposition of disease-associated PrP similarly to human E200K gCJD. Concomitantly we detected aggregated, proteinase K resistant, truncated and oxidized PrP forms on immunoblots. Inoculation of brain extracts from TgMHu2ME199K mice readily induced, the first time for any mutant prion transgenic model, a distinct fatal prion disease in wt mice. We believe that these mice may serve as an ideal platform for the investigation of the pathogenesis of genetic prion disease and thus for the monitoring of anti-prion treatments. PMID:22072968

  2. Fatal prion disease in a mouse model of genetic E200K Creutzfeldt-Jakob disease.

    Directory of Open Access Journals (Sweden)

    Yael Friedman-Levi

    2011-11-01

    Full Text Available Genetic prion diseases are late onset fatal neurodegenerative disorders linked to pathogenic mutations in the prion protein-encoding gene, PRNP. The most prevalent of these is the substitution of Glutamate for Lysine at codon 200 (E200K, causing genetic Creutzfeldt-Jakob disease (gCJD in several clusters, including Jews of Libyan origin. Investigating the pathogenesis of genetic CJD, as well as developing prophylactic treatments for young asymptomatic carriers of this and other PrP mutations, may well depend upon the availability of appropriate animal models in which long term treatments can be evaluated for efficacy and toxicity. Here we present the first effective mouse model for E200KCJD, which expresses chimeric mouse/human (TgMHu2M E199KPrP on both a null and a wt PrP background, as is the case for heterozygous patients and carriers. Mice from both lines suffered from distinct neurological symptoms as early as 5-6 month of age and deteriorated to death several months thereafter. Histopathological examination of the brain and spinal cord revealed early gliosis and age-related intraneuronal deposition of disease-associated PrP similarly to human E200K gCJD. Concomitantly we detected aggregated, proteinase K resistant, truncated and oxidized PrP forms on immunoblots. Inoculation of brain extracts from TgMHu2ME199K mice readily induced, the first time for any mutant prion transgenic model, a distinct fatal prion disease in wt mice. We believe that these mice may serve as an ideal platform for the investigation of the pathogenesis of genetic prion disease and thus for the monitoring of anti-prion treatments.

  3. Adult onset sporadic ataxias: a diagnostic challenge

    Directory of Open Access Journals (Sweden)

    Orlando Graziani Povoas Barsottini

    2014-03-01

    Full Text Available Patients with adult onset non-familial progressive ataxia are classified in sporadic ataxia group. There are several disease categories that may manifest with sporadic ataxia: toxic causes, immune-mediated ataxias, vitamin deficiency, infectious diseases, degenerative disorders and even genetic conditions. Considering heterogeneity in the clinical spectrum of sporadic ataxias, the correct diagnosis remains a clinical challenge. In this review, the different disease categories that lead to sporadic ataxia with adult onset are discussed with special emphasis on their clinical and neuroimaging features, and diagnostic criteria.

  4. Prion propagation and toxicity occur in vitro with two-phase kinetics specific to strain and neuronal type.

    Science.gov (United States)

    Hannaoui, Samia; Maatouk, Layal; Privat, Nicolas; Levavasseur, Etienne; Faucheux, Baptiste A; Haïk, Stéphane

    2013-03-01

    Prion diseases, or transmissible spongiform encephalopathies (TSEs), are fatal neurodegenerative disorders that occur in humans and animals. The neuropathological hallmarks of TSEs are spongiosis, glial proliferation, and neuronal loss. The only known specific molecular marker of TSEs is the abnormal isoform (PrP(Sc)) of the host-encoded prion protein (PrP(C)), which accumulates in the brain of infected subjects and forms infectious prion particles. Although this transmissible agent lacks a specific nucleic acid component, several prion strains have been isolated. Prion strains are characterized by differences in disease outcome, PrP(Sc) distribution patterns, and brain lesion profiles at the terminal stage of the disease. The molecular factors and cellular mechanisms involved in strain-specific neuronal tropism and toxicity remain largely unknown. Currently, no cellular model exists to facilitate in vitro studies of these processes. A few cultured cell lines that maintain persistent scrapie infections have been developed, but only two of them have shown the cytotoxic effects associated with prion propagation. In this study, we have developed primary neuronal cultures to assess in vitro neuronal tropism and toxicity of different prion strains (scrapie strains 139A, ME7, and 22L). We have tested primary neuronal cultures enriched in cerebellar granular, striatal, or cortical neurons. Our results showed that (i) a strain-specific neuronal tropism operated in vitro; (ii) the cytotoxic effect varied among strains and neuronal cell types; (iii) prion propagation and toxicity occurred in two kinetic phases, a replicative phase followed by a toxic phase; and (iv) neurotoxicity peaked when abnormal PrP accumulation reached a plateau.

  5. Direct evidence for a chronic CD8+-T-cell-mediated immune reaction to tax within the muscle of a human T-cell leukemia/lymphoma virus type 1-infected patient with sporadic inclusion body myositis.

    Science.gov (United States)

    Ozden, Simona; Cochet, Madeleine; Mikol, Jacqueline; Teixeira, Antonio; Gessain, Antoine; Pique, Claudine

    2004-10-01

    Human T-cell leukemia/lymphoma virus type 1 (HTLV-1) infection can lead to the development of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), concomitantly with or without other inflammatory disorders such as myositis. These pathologies are considered immune-mediated diseases, and it is assumed that migration within tissues of both HTLV-1-infected CD4(+) T cells and anti-HTLV-1 cytotoxic T cells represents a pivotal event. However, although HTLV-1-infected T cells were found in inflamed lesions, the antigenic specificity of coinfiltrated CD8(+) T cells remains to be determined. In this study, we performed both ex vivo and in situ analyses using muscle biopsies obtained from an HTLV-1-infected patient with HAM/TSP and sporadic inclusion body myositis. We found that both HTLV-1-infected CD4(+) T cells and CD8(+) T cells directed to the dominant Tax antigen can be amplified from muscle cell cultures. Moreover, we were able to detect in two successive muscle biopsies both tax mRNA-positive mononuclear cells and T cells recognized by the Tax11-19/HLA-A*02 tetramer and positive for perforin. These findings provide the first direct demonstration that anti-Tax cytotoxic T cells are chronically recruited within inflamed tissues of an HTLV-1 infected patient, which validates the cytotoxic immune reaction model for the pathogenesis of HTLV-1-associated inflammatory disease.

  6. Accumulation of pathological prion protein PrPSc in the skin of animals with experimental and natural scrapie.

    Directory of Open Access Journals (Sweden)

    Achim Thomzig

    2007-05-01

    Full Text Available Prion infectivity and its molecular marker, the pathological prion protein PrP(Sc, accumulate in the central nervous system and often also in lymphoid tissue of animals or humans affected by transmissible spongiform encephalopathies. Recently, PrP(Sc was found in tissues previously considered not to be invaded by prions (e.g., skeletal muscles. Here, we address the question of whether prions target the skin and show widespread PrP(Sc deposition in this organ in hamsters perorally or parenterally challenged with scrapie. In hamsters fed with scrapie, PrP(Sc was detected before the onset of symptoms, but the bulk of skin-associated PrP(Sc accumulated in the clinical phase. PrP(Sc was localized in nerve fibres within the skin but not in keratinocytes, and the deposition of PrP(Sc in skin showed no dependence from the route of infection and lymphotropic dissemination. The data indicated a neurally mediated centrifugal spread of prions to the skin. Furthermore, in a follow-up study, we examined sheep naturally infected with scrapie and detected PrP(Sc by Western blotting in skin samples from two out of five animals. Our findings point to the skin as a potential reservoir of prions, which should be further investigated in relation to disease transmission.

  7. Ultra-sensitive detection of prion protein fibrils by flow cytometry in blood from cattle affected with bovine spongiform encephalopathy

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    Maas Elke

    2005-10-01

    Full Text Available Abstract Background The definite diagnosis of prion diseases such as Creutzfeldt-Jakob disease (CJD in humans or bovine spongiform encephalopathy (BSE in cattle currently relies on the post mortem detection of the pathological form of the prion protein (PrPSc in brain tissue. Infectivity studies indicate that PrPSc may also be present in body fluids, even at presymptomatic stages of the disease, albeit at concentrations well below the detection limits of currently available analytical methods. Results We developed a highly sensitive method for detecting prion protein aggregates that takes advantage of kinetic differences between seeded and unseeded polymerization of prion protein monomers. Detection of the aggregates was carried out by flow cytometry. In the presence of prion seeds, the association of labelled recombinant PrP monomers in plasma and serum proceeds much more efficiently than in the absence of seeds. In a diagnostic model system, synthetic PrP aggregates were detected down to a concentration of approximately 10-8 nM [0.24 fg/ml]. A specific signal was detected in six out of six available serum samples from BSE-positive cattle. Conclusion We have developed a method based on seed-dependent PrP fibril formation that shows promising results in differentiating a small number of BSE-positive serum samples from healthy controls. This method may provide the basis for an ante mortem diagnostic test for prion diseases.

  8. A systematic investigation of production of synthetic prions from recombinant prion protein.

    Science.gov (United States)

    Schmidt, Christian; Fizet, Jeremie; Properzi, Francesca; Batchelor, Mark; Sandberg, Malin K; Edgeworth, Julie A; Afran, Louise; Ho, Sammy; Badhan, Anjna; Klier, Steffi; Linehan, Jacqueline M; Brandner, Sebastian; Hosszu, Laszlo L P; Tattum, M Howard; Jat, Parmjit; Clarke, Anthony R; Klöhn, Peter C; Wadsworth, Jonathan D F; Jackson, Graham S; Collinge, John

    2015-12-01

    According to the protein-only hypothesis, infectious mammalian prions, which exist as distinct strains with discrete biological properties, consist of multichain assemblies of misfolded cellular prion protein (PrP). A critical test would be to produce prion strains synthetically from defined components. Crucially, high-titre 'synthetic' prions could then be used to determine the structural basis of infectivity and strain diversity at the atomic level. While there have been multiple reports of production of prions from bacterially expressed recombinant PrP using various methods, systematic production of high-titre material in a form suitable for structural analysis remains a key goal. Here, we report a novel high-throughput strategy for exploring a matrix of conditions, additives and potential cofactors that might generate high-titre prions from recombinant mouse PrP, with screening for infectivity using a sensitive automated cell-based bioassay. Overall, approximately 20,000 unique conditions were examined. While some resulted in apparently infected cell cultures, this was transient and not reproducible. We also adapted published methods that reported production of synthetic prions from recombinant hamster PrP, but again did not find evidence of significant infectious titre when using recombinant mouse PrP as substrate. Collectively, our findings are consistent with the formation of prion infectivity from recombinant mouse PrP being a rare stochastic event and we conclude that systematic generation of prions from recombinant PrP may only become possible once the detailed structure of authentic ex vivo prions is solved. © 2015 The Authors.

  9. Defining the Conformational Features of Anchorless, Poorly Neuroinvasive Prions

    NARCIS (Netherlands)

    Bett, C.; Kurt, T.D.; Lucero, M.; Trejo, M.; Rozemuller, A.J.M.; Kong, Q.Z.; Nilsson, K.P.R.; Masliah, E.; Oldstone, M.B.; Sigurdson, C.J.

    2013-01-01

    Infectious prions cause diverse clinical signs and form an extraordinary range of structures, from amorphous aggregates to fibrils. How the conformation of a prion dictates the disease phenotype remains unclear. Mice expressing GPI-anchorless or GPI-anchored prion protein exposed to the same

  10. Prion disease tempo determined by host-dependent substrate reduction

    NARCIS (Netherlands)

    Mays, C.E.; Kim, C.; Haldiman, T.; Merwe, v.d. J.; Lau, A.; Yang, J.; Grams, J.; Bari, Di M.A.; Nonno, R.; Telling, G.C.; Kong, Q.; Langeveld, J.P.M.; McKenzie, D.; Westaway, D.; Safar, J.G.

    2014-01-01

    The symptoms of prion infection can take years or decades to manifest following the initial exposure. Molecular markers of prion disease include accumulation of the misfolded prion protein (PrPSc), which is derived from its cellular precursor (PrPC), as well as downregulation of the PrP-like Shadoo

  11. Prions in milk from ewes incubating natural scrapie.

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    Caroline Lacroux

    2008-12-01

    Full Text Available Since prion infectivity had never been reported in milk, dairy products originating from transmissible spongiform encephalopathy (TSE-affected ruminant flocks currently enter unrestricted into the animal and human food chain. However, a recently published study brought the first evidence of the presence of prions in mammary secretions from scrapie-affected ewes. Here we report the detection of consistent levels of infectivity in colostrum and milk from sheep incubating natural scrapie, several months prior to clinical onset. Additionally, abnormal PrP was detected, by immunohistochemistry and PET blot, in lacteal ducts and mammary acini. This PrP(Sc accumulation was detected only in ewes harbouring mammary ectopic lymphoid follicles that developed consequent to Maedi lentivirus infection. However, bioassay revealed that prion infectivity was present in milk and colostrum, not only from ewes with such lympho-proliferative chronic mastitis, but also from those displaying lesion-free mammary glands. In milk and colostrum, infectivity could be recovered in the cellular, cream, and casein-whey fractions. In our samples, using a Tg 338 mouse model, the highest per ml infectious titre measured was found to be equivalent to that contained in 6 microg of a posterior brain stem from a terminally scrapie-affected ewe. These findings indicate that both colostrum and milk from small ruminants incubating TSE could contribute to the animal TSE transmission process, either directly or through the presence of milk-derived material in animal feedstuffs. It also raises some concern with regard to the risk to humans of TSE exposure associated with milk products from ovine and other TSE-susceptible dairy species.

  12. 76 FR 71294 - Prions; Proposed Amendment To Clarify Product Performance Data for Products With Prion-Related...

    Science.gov (United States)

    2011-11-17

    ... (FIFRA), and to amend its regulations to expressly include prion within the regulatory definition of pest... observed by the user including, but not limited to, microorganisms infectious to man in any area of the... prion within the regulatory definition of pest. EPA currently considers a prion to be a pest under FIFRA...

  13. Quantifying the relative amounts of PrP polymorphisms present in prions isolated from heterozygous prion-infected animals

    Science.gov (United States)

    Prions cause protein misfolding diseases, such as transmissible spongiform encephalopathy. They propagate infections by converting a normal cellular prion protein into a prion (PrPSc). PrPC and PrPSc are isosequential and differ only in their respective conformations. PrPC is monomeric and sensit...

  14. High resolution human leukocyte antigen (HLA) class I and class II allele typing in Mexican mestizo women with sporadic breast cancer: case-control study

    International Nuclear Information System (INIS)

    Cantú de León, David; Yu, Neng; Yunis, Edmond J; Granados, Julio; Pérez-Montiel, Delia; Villavicencio, Verónica; Carranca, Alejandro García; Betancourt, Alejandro Mohar; Acuña-Alonzo, Victor; López-Tello, Alberto; Vargas-Alarcón, Gilberto; Barquera, Rodrigo

    2009-01-01

    The development of breast cancer is multifactorial. Hormonal, environmental factors and genetic predisposition, among others, could interact in the presentation of breast carcinoma. Human leukocyte antigen (HLA) alleles play an important role in immunity (cellular immunity) and may be important genetic traits. HLAAllele-specific interaction has not been well established. Recently, several studies had been conducted in order to do so, but the results are controversial and in some instances contradictory. We designed a case-control study to quantify the association of HLA class I and II genes and breast cancer. HLA typing was performed by high resolution sequence-specific oligotyping after DNA amplification (PCR-SSOP) of 100 breast cancer Mexican mestizo patients and 99 matched healthy controls. HLA-A frequencies that we were able to observe that there was no difference between both groups from the statistical viewpoint. HLA-B*1501 was found three times more common in the case group (OR, 3.714; p = 0.031). HLA-Cw is not a marker neither for risk, nor protection for the disease, because we did not find significant statistical differences between the two groups. DRB1*1301, which is expressed in seven cases and in only one control, observing an risk increase of up to seven times and DRB1*1602, which behaves similarly in being present solely in the cases (OR, 16.701; 95% CI, 0.947 – 294.670). DQ*0301-allele expression, which is much more common in the control group and could be protective for the presentation of the disease (OR, 0.078; 95% CI, 0.027–0.223, p = 0.00001). Our results reveal the role of the MHC genes in the pathophysiology of breast cancer, suggesting that in the development of breast cancer exists a disorder of immune regulation. The triggering factor seems to be restricted to certain ethnic groups and certain geographical regions since the relevant MHC alleles are highly diverse. This is the first study in Mexican population where high resolutions HLA

  15. Validation of 14-3-3 Protein as a Marker in Sporadic Creutzfeldt-Jakob Disease Diagnostic.

    Science.gov (United States)

    Schmitz, Matthias; Ebert, Elisabeth; Stoeck, Katharina; Karch, André; Collins, Steven; Calero, Miguel; Sklaviadis, Theodor; Laplanche, Jean-Louis; Golanska, Ewa; Baldeiras, Ines; Satoh, Katsuya; Sanchez-Valle, Raquel; Ladogana, Anna; Skinningsrud, Anders; Hammarin, Anna-Lena; Mitrova, Eva; Llorens, Franc; Kim, Yong Sun; Green, Alison; Zerr, Inga

    2016-05-01

    At present, the testing of 14-3-3 protein in cerebrospinal fluid (CSF) is a standard biomarker test in suspected sporadic Creutzfeldt-Jakob disease (sCJD) diagnosis. Increasing 14-3-3 test referrals in CJD reference laboratories in the last years have led to an urgent need to improve established 14-3-3 test methods. The main result of our study was the validation of a commercially available 14-3-3 ELISA next to the commonly used Western blot method as a high-throughput screening test. Hereby, 14-3-3 protein expression was quantitatively analyzed in CSF of 231 sCJD and 2035 control patients. We obtained excellent sensitivity/specificity values of 88 and 96% that are comparable to the established Western blot method. Since standard protocols and preanalytical sample handling have become more important in routine diagnostic, we investigated in a further step the reproducibility and stability of 14-3-3 as a biomarker for human prion diseases. Ring trial data from 2009 to 2013 revealed an increase of Fleiss' kappa from 0.51 to 0.68 indicating an improving reliability of 14-3-3 protein detection. The stability of 14-3-3 protein under short-term and long-term storage conditions at various temperatures and after repeated freezing/thawing cycles was confirmed. Contamination of CSF samples with blood appears likely to be an important factor at a concentration of more than 2500 erythrocytes/μL. Hemolysis of erythrocytes with significant release of 14-3-3 protein started after 2 days at room temperature. We first define clear standards for the sample handling, short- and long-term storage of CSF samples as well as the handling of blood- contaminated samples which may result in artificially elevated CSF levels of 14-3-3.

  16. Lions and prions and deer demise.

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    Michael W Miller

    Full Text Available BACKGROUND: Contagious prion diseases--scrapie of sheep and chronic wasting disease of several species in the deer family--give rise to epidemics that seem capable of compromising host population viability. Despite this prospect, the ecological consequences of prion disease epidemics in natural populations have received little consideration. METHODOLOGY/PRINCIPAL FINDINGS: Using a cohort study design, we found that prion infection dramatically lowered survival of free-ranging adult (>2-year-old mule deer (Odocoileus hemionus: estimated average life expectancy was 5.2 additional years for uninfected deer but only 1.6 additional years for infected deer. Prion infection also increased nearly fourfold the rate of mountain lions (Puma concolor preying on deer, suggesting that epidemics may alter predator-prey dynamics by facilitating hunting success. Despite selective predation, about one fourth of the adult deer we sampled were infected. High prevalence and low survival of infected deer provided a plausible explanation for the marked decline in this deer population since the 1980s. CONCLUSION: Remarkably high infection rates sustained in the face of intense predation show that even seemingly complete ecosystems may offer little resistance to the spread and persistence of contagious prion diseases. Moreover, the depression of infected populations may lead to local imbalances in food webs and nutrient cycling in ecosystems in which deer are important herbivores.

  17. Accuracy of diagnosis criteria in patients with suspected diagnosis of sporadic Creutzfeldt-Jakob disease and detection of 14-3-3 protein, France, 1992 to 2009.

    Science.gov (United States)

    Peckeu, Laurene; Delasnerie-Lauprètre, Nicole; Brandel, Jean-Philippe; Salomon, Dominique; Sazdovitch, Véronique; Laplanche, Jean-Louis; Duyckaerts, Charles; Seilhean, Danielle; Haïk, Stéphane; Hauw, Jean-Jacques

    2017-10-01

    Diagnostic criteria of Creutzfeldt-Jakob disease (CJD), a rare and fatal transmissible nervous system disease with public health implications, are determined by clinical data, electroencephalogram (EEG), detection of 14-3-3 protein in cerebrospinal fluid (CSF), brain magnetic resonance imaging and prion protein gene examination. The specificity of protein 14-3-3 has been questioned. We reviewed data from 1,572 autopsied patients collected over an 18-year period (1992-2009) and assessed whether and how 14-3-3 detection impacted the diagnosis of sporadic CJD in France, and whether this led to the misdiagnosis of treatable disorders. 14-3-3 detection was introduced into diagnostic criteria for CJD in 1998. Diagnostic accuracy decreased from 92% for the 1992-1997 period to 85% for the 1998-2009 period. This was associated with positive detections of 14-3-3 in cases with negative EEG and alternative diagnosis at autopsy. Potentially treatable diseases were found in 163 patients (10.5%). This study confirms the usefulness of the recent modification of diagnosis criteria by the addition of the results of CSF real-time quaking-induced conversion, a method based on prion seed-induced misfolding and aggregation of recombinant prion protein substrate that has proven to be a highly specific test for diagnosis of sporadic CJD.

  18. Secretin receptor involvement in prion-infected cells and animals.

    Science.gov (United States)

    Kimura, Tomohiro; Nishizawa, Keiko; Oguma, Ayumi; Nishimura, Yuki; Sakasegawa, Yuji; Teruya, Kenta; Nishijima, Ichiko; Doh-ura, Katsumi

    2015-07-08

    The cellular mechanisms behind prion biosynthesis and metabolism remain unclear. Here we show that secretin signaling via the secretin receptor regulates abnormal prion protein formation in prion-infected cells. Animal studies demonstrate that secretin receptor deficiency slightly, but significantly, prolongs incubation time in female but not male mice. This gender-specificity is consistent with our finding that prion-infected cells are derived from females. Therefore, our results provide initial insights into the reasons why age of disease onset in certain prion diseases is reported to occur slightly earlier in females than males. Copyright © 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  19. [Doctor Francoise Cathala and history of prions diseases].

    Science.gov (United States)

    Court, L; Hauw, J-J

    2015-12-01

    Doctor Françoise Cathala Pagesy, MD, MS, born on July 7, 1921 in Paris, passed away peacefully at home on November 5, 2012. Unconventional, passionate and enthusiastic neurologist and virologist, she devoted her life to research on latent and slow viral infections, specializing mainly on unconventional transmissible agents or prions. As a research member of Inserm (French Institute for Medical Research), she soon joined the team of Carlton Gajdusek (the NINCDS - National Institute of Nervous Central System and Stroke - of NIH), who first demonstrated the transmissibility of kuru and Creutzfeldt-Jakob disease to monkeys. When she came back to Paris, where she was followed by one of NIH members, Paul Brown, she joined the Centre de Recherches du Service de Santé des Armées (Army Health Research Center), in Percy-Clamart, where she found the experimental design and the attentive help needed for her research, which appeared heretical to many French virologists, including some authorities. A large number of research programs were set up with numerous collaborations involving CEA (Center for Atomic Energy) and other institutions in Paris and Marseilles on epidemiology, results of tissue inoculation, electrophysiology and neuropathology of human and animal prions diseases, and resistance of the infectious agent. International symposia were set up, where met, in the Val-de-Grâce hospital in Paris, the research community on "slow viral diseases". Stanley Prusiner introduced the concept - then badly accepted and still in evolution - of prion, a protein only infectious agent. Before retiring from Inserm, Françoise Cathala predicted and was involved in some of the huge sanitary crises in France. These were, first, Creutzfeldt-Jakob disease from contaminated growth hormone extracted from cadavers, which led parents to instigate legal procedure - a quite unusual practice in France. The second was Mad cow disease in the United Kingdom then in France, followed by new variant

  20. Cerebrospinal fluid tau levels are a marker for molecular subtype in sporadic Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Karch, André; Hermann, Peter; Ponto, Claudia; Schmitz, Matthias; Arora, Amandeep; Zafar, Saima; Llorens, Franc; Müller-Heine, Annika; Zerr, Inga

    2015-05-01

    The molecular subtype of sporadic Creutzfeldt-Jakob disease (sCJD) is an important prognostic marker for patient survival. However, subtype determination is not possible during lifetime. Because the rate of disease progression is associated with the molecular subtype, this study aimed at investigating if total tau, a marker of neuronal death, allows premortem diagnosis of molecular subtype when codon 129 genotype is known. Two hundred ninety-six sCJD patients were tested for their cerebrospinal fluid total tau level at the time of diagnosis and were investigated for their sCJD subtype postmortem. There was a significant association between tau levels and the prion protein type in patients with codon 129 MM (p disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Grass Plants Bind, Retain, Uptake, and Transport Infectious Prions

    Directory of Open Access Journals (Sweden)

    Sandra Pritzkow

    2015-05-01

    Full Text Available Prions are the protein-based infectious agents responsible for prion diseases. Environmental prion contamination has been implicated in disease transmission. Here, we analyzed the binding and retention of infectious prion protein (PrPSc to plants. Small quantities of PrPSc contained in diluted brain homogenate or in excretory materials (urine and feces can bind to wheat grass roots and leaves. Wild-type hamsters were efficiently infected by ingestion of prion-contaminated plants. The prion-plant interaction occurs with prions from diverse origins, including chronic wasting disease. Furthermore, leaves contaminated by spraying with a prion-containing preparation retained PrPSc for several weeks in the living plant. Finally, plants can uptake prions from contaminated soil and transport them to aerial parts of the plant (stem and leaves. These findings demonstrate that plants can efficiently bind infectious prions and act as carriers of infectivity, suggesting a possible role of environmental prion contamination in the horizontal transmission of the disease.

  2. Grass plants bind, retain, uptake, and transport infectious prions.

    Science.gov (United States)

    Pritzkow, Sandra; Morales, Rodrigo; Moda, Fabio; Khan, Uffaf; Telling, Glenn C; Hoover, Edward; Soto, Claudio

    2015-05-26

    Prions are the protein-based infectious agents responsible for prion diseases. Environmental prion contamination has been implicated in disease transmission. Here, we analyzed the binding and retention of infectious prion protein (PrP(Sc)) to plants. Small quantities of PrP(Sc) contained in diluted brain homogenate or in excretory materials (urine and feces) can bind to wheat grass roots and leaves. Wild-type hamsters were efficiently infected by ingestion of prion-contaminated plants. The prion-plant interaction occurs with prions from diverse origins, including chronic wasting disease. Furthermore, leaves contaminated by spraying with a prion-containing preparation retained PrP(Sc) for several weeks in the living plant. Finally, plants can uptake prions from contaminated soil and transport them to aerial parts of the plant (stem and leaves). These findings demonstrate that plants can efficiently bind infectious prions and act as carriers of infectivity, suggesting a possible role of environmental prion contamination in the horizontal transmission of the disease. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Quantitative Expression Analysis of APP Pathway and Tau Phosphorylation-Related Genes in the ICV STZ-Induced Non-Human Primate Model of Sporadic Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Sang-Je Park

    2015-01-01

    Full Text Available The accumulation and aggregation of misfolded proteins in the brain, such as amyloid-β (Aβ and hyperphosphorylated tau, is a neuropathological hallmark of Alzheimer’s disease (AD. Previously, we developed and validated a novel non-human primate model for sporadic AD (sAD research using intracerebroventricular administration of streptozotocin (icv STZ. To date, no characterization of AD-related genes in different brain regions has been performed. Therefore, in the current study, the expression of seven amyloid precursor protein (APP pathway-related and five tau phosphorylation-related genes was investigated by quantitative real-time PCR experiments, using two matched-pair brain samples from control and icv STZ-treated cynomolgus monkeys. The genes showed similar expression patterns within the control and icv STZ-treated groups; however, marked differences in gene expression patterns were observed between the control and icv STZ-treated groups. Remarkably, other than β-secretase (BACE1 and cyclin-dependent kinase 5 (CDK5, all the genes tested showed similar expression patterns in AD models compared to controls, with increased levels in the precuneus and occipital cortex. However, significant changes in gene expression patterns were not detected in the frontal cortex, hippocampus, or posterior cingulate. Based on these results, we conclude that APP may be cleaved via the general metabolic mechanisms of increased α- and γ-secretase levels, and that hyperphosphorylation of tau could be mediated by elevated levels of tau protein kinase, specifically in the precuneus and occipital cortex.

  4. Sporadic Creutzfeldt-Jakob disease in a native Puerto Rican patient.

    Science.gov (United States)

    Del Pilar-Morales, Esteban A; Cali, Ignazio; Chapas, Javier; Bertrán-Pasarell, Jorge; Puoti, Gianfranco; Gambetti, Pierluigi; Nobo, Ulises

    2015-03-01

    The diagnosis of Creutzfeldt-Jakob disease (CJD) is often a challenge for most physicians given its extremely low incidence and different clinico-pathological presentations. We report the case of a 56-year old patient native to Puerto Rico suspected of sporadic Creutzfeldt-Jakob disease (sCD). The symptoms at onset were notorious for bilateral cortical blindness followed by rapidly progressive cognitive decline, visual deficit, increased levels of CSF 14-3-3 and tau along with positive brain MRI and EEG, are highly indicative of CJD. The definite diagnosis was confirmed by the National Prion Disease Pathology Surveillance Center (NPDPSC), in Cleveland, Ohio, USA. Lack of genetic mutations in the prion protein (PrP) gene, widespread histopathological changes and the accumulation of scrapie PrP (PrPSc) in the brain confirmed the diagnosis of sCJD. The patient, admitted to our institution in 2011, represents the first detailed report of sCJD in a native Puerto Rican patient living in Puerto Rico.

  5. Insights into the physiological function of cellular prion protein

    Directory of Open Access Journals (Sweden)

    Martins V.R.

    2001-01-01

    Full Text Available Prions have been extensively studied since they represent a new class of infectious agents in which a protein, PrPsc (prion scrapie, appears to be the sole component of the infectious particle. They are responsible for transmissible spongiform encephalopathies, which affect both humans and animals. The mechanism of disease propagation is well understood and involves the interaction of PrPsc with its cellular isoform (PrPc and subsequently abnormal structural conversion of the latter. PrPc is a glycoprotein anchored on the cell surface by a glycosylphosphatidylinositol moiety and expressed in most cell types but mainly in neurons. Prion diseases have been associated with the accumulation of the abnormally folded protein and its neurotoxic effects; however, it is not known if PrPc loss of function is an important component. New efforts are addressing this question and trying to characterize the physiological function of PrPc. At least four different mouse strains in which the PrP gene was ablated were generated and the results regarding their phenotype are controversial. Localization of PrPc on the cell membrane makes it a potential candidate for a ligand uptake, cell adhesion and recognition molecule or a membrane signaling molecule. Recent data have shown a potential role for PrPc in the metabolism of copper and moreover that this metal stimulates PrPc endocytosis. Our group has recently demonstrated that PrPc is a high affinity laminin ligand and that this interaction mediates neuronal cell adhesion and neurite extension and maintenance. Moreover, PrPc-caveolin-1 dependent coupling seems to trigger the tyrosine kinase Fyn activation. These data provide the first evidence for PrPc involvement in signal transduction.

  6. Prions in the Urine of Patients with Variant Creutzfeldt–Jakob Disease

    Science.gov (United States)

    Moda, Fabio; Gambetti, Pierluigi; Notari, Silvio; Concha-Marambio, Luis; Catania, Marcella; Park, Kyung-Won; Maderna, Emanuela; Suardi, Silvia; Haïk, Stéphane; Brandel, Jean-Philippe; Ironside, James; Knight, Richard; Tagliavini, Fabrizio; Soto, Claudio

    2014-01-01

    BACKGROUND Prions, the infectious agents responsible for transmissible spongiform encephalopathies, consist mainly of the misfolded prion protein (PrPSc). The unique mechanism of transmission and the appearance of a variant form of Creutzfeldt–Jakob disease, which has been linked to consumption of prion-contaminated cattle meat, have raised concerns about public health. Evidence suggests that variant Creutzfeldt–Jakob disease prions circulate in body fluids from people in whom the disease is silently incubating. METHODS To investigate whether PrPSc can be detected in the urine of patients with variant Creutzfeldt–Jakob disease, we used the protein misfolding cyclic amplification (PMCA) technique to amplify minute quantities of PrPSc, enabling highly sensitive detection of the protein. We analyzed urine samples from several patients with various transmissible spongiform encephalopathies (variant and sporadic Creutzfeldt–Jakob disease and genetic forms of prion disease), patients with other degenerative or nondegenerative neurologic disorders, and healthy persons. RESULTS PrPSc was detectable only in the urine of patients with variant Creutzfeldt–Jakob disease and had the typical electrophoretic profile associated with this disease. PrPSc was detected in 13 of 14 urine samples obtained from patients with variant Creutzfeldt–Jakob disease and in none of the 224 urine samples obtained from patients with other neurologic diseases and from healthy controls, resulting in an estimated sensitivity of 92.9% (95% confidence interval [CI], 66.1 to 99.8) and a specificity of 100.0% (95% CI, 98.4 to 100.0). The PrPSc concentration in urine calculated by means of quantitative PMCA was estimated at 1×10−16 g per milliliter, or 3×10−21 mol per milliliter, which extrapolates to approximately 40 to 100 oligomeric particles of PrPSc per milliliter of urine. CONCLUSIONS Urine samples obtained from patients with variant Creutzfeldt–Jakob disease contained minute

  7. Prions in the urine of patients with variant Creutzfeldt-Jakob disease.

    Science.gov (United States)

    Moda, Fabio; Gambetti, Pierluigi; Notari, Silvio; Concha-Marambio, Luis; Catania, Marcella; Park, Kyung-Won; Maderna, Emanuela; Suardi, Silvia; Haïk, Stéphane; Brandel, Jean-Philippe; Ironside, James; Knight, Richard; Tagliavini, Fabrizio; Soto, Claudio

    2014-08-07

    Prions, the infectious agents responsible for transmissible spongiform encephalopathies, consist mainly of the misfolded prion protein (PrP(Sc)). The unique mechanism of transmission and the appearance of a variant form of Creutzfeldt-Jakob disease, which has been linked to consumption of prion-contaminated cattle meat, have raised concerns about public health. Evidence suggests that variant Creutzfeldt-Jakob disease prions circulate in body fluids from people in whom the disease is silently incubating. To investigate whether PrP(Sc) can be detected in the urine of patients with variant Creutzfeldt-Jakob disease, we used the protein misfolding cyclic amplification (PMCA) technique to amplify minute quantities of PrP(Sc), enabling highly sensitive detection of the protein. We analyzed urine samples from several patients with various transmissible spongiform encephalopathies (variant and sporadic Creutzfeldt-Jakob disease and genetic forms of prion disease), patients with other degenerative or nondegenerative neurologic disorders, and healthy persons. PrP(Sc) was detectable only in the urine of patients with variant Creutzfeldt-Jakob disease and had the typical electrophoretic profile associated with this disease. PrP(Sc) was detected in 13 of 14 urine samples obtained from patients with variant Creutzfeldt-Jakob disease and in none of the 224 urine samples obtained from patients with other neurologic diseases and from healthy controls, resulting in an estimated sensitivity of 92.9% (95% confidence interval [CI], 66.1 to 99.8) and a specificity of 100.0% (95% CI, 98.4 to 100.0). The PrP(Sc) concentration in urine calculated by means of quantitative PMCA was estimated at 1×10(-16) g per milliliter, or 3×10(-21) mol per milliliter, which extrapolates to approximately 40 to 100 oligomeric particles of PrP(Sc) per milliliter of urine. Urine samples obtained from patients with variant Creutzfeldt-Jakob disease contained minute quantities of PrP(Sc). (Funded by the

  8. Mutation directional selection sheds light on prion pathogenesis

    International Nuclear Information System (INIS)

    Shen, Liang; Ji, Hong-Fang

    2011-01-01

    Highlights: → Most pathogenic mutations possess strong directional selection, i.e., enhancing hydrophobicity or decreasing negative and increasing positive charge. → Mutation-induced changes may strengthen the interactions between PrP and facilitating factors. → The findings also have significant implications for exploring potential regions involved in the conformational transition from PrP C to PrP Sc . -- Abstract: As mutations in the PRNP gene account for human hereditary prion diseases (PrDs), it is crucial to elucidating how these mutations affect the central pathogenic conformational transition of normal cellular prion protein (PrP C ) to abnormal scrapie isoform (PrP Sc ). Many studies proposed that these pathogenic mutations may make PrP more susceptible to conformational change through altering its structure stability. By evaluating the most recent observations regarding pathogenic mutations, it was found that the pathogenic mutations do not exert a uniform effect on the thermodynamic stability of the human PrP's structure. Through analyzing the reported PrDs-related mutations, we found that 25 out of 27 mutations possess strong directional selection, i.e., enhancing hydrophobicity or decreasing negative and increasing positive charge. Based on the triggering role reported by previous studies of facilitating factors in PrP C conversion, e.g., lipid and polyanion, we proposed that the mutation-induced changes may strengthen the interaction between PrP and facilitating factors, which will accelerate PrP conversion and cause PrDs.

  9. Lesion of the olfactory epithelium accelerates prion neuroinvasion and disease onset when prion replication is restricted to neurons.

    Directory of Open Access Journals (Sweden)

    Jenna Crowell

    Full Text Available Natural prion diseases of ruminants are moderately contagious and while the gastrointestinal tract is the primary site of prion agent entry, other mucosae may be entry sites in a subset of infections. In the current study we examined prion neuroinvasion and disease induction following disruption of the olfactory epithelium in the nasal mucosa since this site contains environmentally exposed olfactory sensory neurons that project directly into the central nervous system. Here we provide evidence for accelerated prion neuroinvasion and clinical onset from the olfactory mucosa after disruption and regeneration of the olfactory epithelium and when prion replication is restricted to neurons. In transgenic mice with neuron restricted replication of prions, there was a reduction in survival when the olfactory epithelium was disrupted prior to intranasal inoculation and there was >25% decrease in the prion incubation period. In a second model, the neurotropic DY strain of transmissible mink encephalopathy was not pathogenic in hamsters by the nasal route, but 50% of animals exhibited brain infection and/or disease when the olfactory epithelium was disrupted prior to intranasal inoculation. A time course analysis of prion deposition in the brain following loss of the olfactory epithelium in models of neuron-restricted prion replication suggests that neuroinvasion from the olfactory mucosa is via the olfactory nerve or brain stem associated cranial nerves. We propose that induction of neurogenesis after damage to the olfactory epithelium can lead to prion infection of immature olfactory sensory neurons and accelerate prion spread to the brain.

  10. Effects of solution chemistry and aging time on prion protein adsorption and replication of soil-bound prions.

    Directory of Open Access Journals (Sweden)

    Samuel E Saunders

    2011-04-01

    Full Text Available Prion interactions with soil may play an important role in the transmission of chronic wasting disease (CWD and scrapie. Prions are known to bind to a wide range of soil surfaces, but the effects of adsorption solution chemistry and long-term soil binding on prion fate and transmission risk are unknown. We investigated HY TME prion protein (PrP(Sc adsorption to soil minerals in aqueous solutions of phosphate buffered saline (PBS, sodium chloride, calcium chloride, and deionized water using western blotting. The replication efficiency of bound prions following adsorption in these solutions was also evaluated by protein misfolding cyclic amplification (PMCA. Aging studies investigated PrP(Sc desorption and replication efficiency up to one year following adsorption in PBS or DI water. Results indicate that adsorption solution chemistry can affect subsequent prion replication or desorption ability, especially after incubation periods of 30 d or longer. Observed effects were minor over the short-term (7 d or less. Results of long-term aging experiments demonstrate that unbound prions or prions bound to a diverse range of soil surfaces can readily replicate after one year. Our results suggest that while prion-soil interactions can vary with solution chemistry, prions bound to soil could remain a risk for transmitting prion diseases after months in the environment.

  11. Lesion of the Olfactory Epithelium Accelerates Prion Neuroinvasion and Disease Onset when Prion Replication Is Restricted to Neurons

    Science.gov (United States)

    Crowell, Jenna; Wiley, James A.; Bessen, Richard A.

    2015-01-01

    Natural prion diseases of ruminants are moderately contagious and while the gastrointestinal tract is the primary site of prion agent entry, other mucosae may be entry sites in a subset of infections. In the current study we examined prion neuroinvasion and disease induction following disruption of the olfactory epithelium in the nasal mucosa since this site contains environmentally exposed olfactory sensory neurons that project directly into the central nervous system. Here we provide evidence for accelerated prion neuroinvasion and clinical onset from the olfactory mucosa after disruption and regeneration of the olfactory epithelium and when prion replication is restricted to neurons. In transgenic mice with neuron restricted replication of prions, there was a reduction in survival when the olfactory epithelium was disrupted prior to intranasal inoculation and there was >25% decrease in the prion incubation period. In a second model, the neurotropic DY strain of transmissible mink encephalopathy was not pathogenic in hamsters by the nasal route, but 50% of animals exhibited brain infection and/or disease when the olfactory epithelium was disrupted prior to intranasal inoculation. A time course analysis of prion deposition in the brain following loss of the olfactory epithelium in models of neuron-restricted prion replication suggests that neuroinvasion from the olfactory mucosa is via the olfactory nerve or brain stem associated cranial nerves. We propose that induction of neurogenesis after damage to the olfactory epithelium can lead to prion infection of immature olfactory sensory neurons and accelerate prion spread to the brain. PMID:25822718

  12. Treatment with a non-toxic, self-replicating anti-prion delays or prevents prion disease in vivo.

    Science.gov (United States)

    Diaz-Espinoza, R; Morales, R; Concha-Marambio, L; Moreno-Gonzalez, I; Moda, F; Soto, C

    2018-03-01

    Transmissible spongiform encephalopathies (TSEs) are fatal neurological disorders caused by prions, which are composed of a misfolded protein (PrP Sc ) that self-propagates in the brain of infected individuals by converting the normal prion protein (PrP C ) into the pathological isoform. Here, we report a novel experimental strategy for preventing prion disease based on producing a self-replicating, but innocuous PrP Sc -like form, termed anti-prion, which can compete with the replication of pathogenic prions. Our results show that a prophylactic inoculation of prion-infected animals with an anti-prion delays the onset of the disease and in some animals completely prevents the development of clinical symptoms and brain damage. The data indicate that a single injection of the anti-prion eliminated ~99% of the infectivity associated to pathogenic prions. Furthermore, this treatment caused significant changes in the profile of regional PrP Sc deposition in the brains of animals that were treated, but still succumbed to the disease. Our findings provide new insights for a mechanistic understanding of prion replication and support the concept that prion replication can be separated from toxicity, providing a novel target for therapeutic intervention.

  13. Prion Protein on Astrocytes or in Extracellular Fluid Impedes Neurodegeneration Induced by Truncated Prion Protein

    OpenAIRE

    Race, Brent; Meade-White, Kimberly; Race, Richard; Baumann, Frank; Aguzzi, Adriano; Chesebro, Bruce

    2009-01-01

    Prion protein (PrP) is a host-encoded membrane-anchored glycoprotein which is required for susceptibility to prion disease. PrP may also be important for normal brain functions such as hippocampal spatial memory. Previously transgenic mice expressing amino terminally truncated mouse PrP (Δ32–134) spontaneously developed a fatal disease associated with degeneration of cerebellar granular neurons as well as vacuolar degeneration of deep cerebellar and brain stem white matter. This disease could...

  14. Interaction of the 106-126 prion peptide with lipid membranes and potential implication for neurotoxicity

    International Nuclear Information System (INIS)

    Dupiereux, Ingrid; Zorzi, Willy; Lins, Laurence; Brasseur, Robert; Colson, Pierre; Heinen, Ernst; Elmoualij, Benaissa

    2005-01-01

    Prion diseases are fatal neurodegenerative disorders characterized by the accumulation in the brain of an abnormally misfolded, protease-resistant, and β-sheet rich pathogenic isoform (PrP sc ) of the cellular prion protein (PrP c ). In the present work, we were interested to study the mode of prion protein interaction with the membrane using the 106-126 peptide and small unilamellar lipid vesicles as model. As previously demonstrated, we showed by MTS assay that PrP 106-126 induces alterations in the human neuroblastoma SH-SY5Y cell line. We demonstrated for the first time by lipid-mixing assay and by the liposome vesicle leakage test that PrP 106-126, a non-tilted peptide, induces liposome fusion thus a potential cell membrane destabilization, as supported by membrane integrity assay (LDH). By circular dichroism (CD) analysis we showed that the fusogenic property of PrP 106-126 in the presence of liposome is associated with a predominantly β-sheet structure. These data suggest that the fusogenic property associated with a predominant β-sheet structure exhibited by the prion peptides contributes to the neurotoxicity of these peptides by destabilizing cellular membranes. The latter might be attached at the membrane surface in a parallel orientation as shown by molecular modeling

  15. LRP1 controls biosynthetic and endocytic trafficking of neuronal prion protein

    DEFF Research Database (Denmark)

    Parkyn, Celia J; Vermeulen, Esmeralda G M; Mootoosamy, Roy C

    2008-01-01

    The trafficking of normal cellular prion protein (PrP(C)) is believed to control its conversion to the altered conformation (designated PrP(Sc)) associated with prion disease. Although anchored to the membrane by means of glycosylphosphatidylinositol (GPI), PrP(C) on neurons is rapidly and consti......The trafficking of normal cellular prion protein (PrP(C)) is believed to control its conversion to the altered conformation (designated PrP(Sc)) associated with prion disease. Although anchored to the membrane by means of glycosylphosphatidylinositol (GPI), PrP(C) on neurons is rapidly...... required for this process. Moreover, sustained inhibition of LRP1 levels by siRNA leads to the accumulation of PrP(C) in biosynthetic compartments, with a concomitant lowering of surface PrP(C), suggesting that LRP1 expedites the trafficking of PrP(C) to the neuronal surface. PrP(C) and LRP1 can be co......-immunoprecipitated from the endoplasmic reticulum in normal neurons. The N-terminal domain of PrP(C) binds to purified human LRP1 with nanomolar affinity, even in the presence of 1 microM of the LRP-specific chaperone, receptor-associated protein (RAP). Taken together, these data argue that LRP1 controls both the surface...

  16. The Role of the Mammalian Prion Protein in the Control of Sleep

    Directory of Open Access Journals (Sweden)

    Amber Roguski

    2017-11-01

    Full Text Available Sleep disruption is a prevalent clinical feature in many neurodegenerative disorders, including human prion diseases where it can be the defining dysfunction, as in the case of the “eponymous” fatal familial insomnia, or an early-stage symptom as in certain types of Creutzfeldt-Jakob disease. It is important to establish the role of the cellular prion protein (PrPC, the key molecule involved in prion pathogenesis, within the sleep-wake system in order to understand fully the mechanisms underlying its contribution to both healthy circadian rhythmicity and sleep dysfunction during disease. Although severe disruption to the circadian rhythm and melatonin release is evident during the pathogenic phases of some prion diseases, untangling whether PrPC plays a role in circadian rhythmicity, as suggested in mice deficient for PrPC expression, is challenging given the lack of basic experimental research. We provide a short review of the small amount of direct literature focused on the role of PrPC in melatonin and circadian rhythm regulation, as well as suggesting mechanisms by which PrPC might exert influence upon noradrenergic and dopaminergic signaling and melatonin synthesis. Future research in this area should focus upon isolating the points of dysfunction within the retino-pineal pathway and further investigate PrPC mediation of pinealocyte GPCR activity.

  17. Role of Prion Replication in the Strain-dependent Brain Regional Distribution of Prions.

    Science.gov (United States)

    Hu, Ping Ping; Morales, Rodrigo; Duran-Aniotz, Claudia; Moreno-Gonzalez, Ines; Khan, Uffaf; Soto, Claudio

    2016-06-10

    One intriguing feature of prion diseases is their strain variation. Prion strains are differentiated by the clinical consequences they generate in the host, their biochemical properties, and their potential to infect other animal species. The selective targeting of these agents to specific brain structures have been extensively used to characterize prion strains. However, the molecular basis dictating strain-specific neurotropism are still elusive. In this study, isolated brain structures from animals infected with four hamster prion strains (HY, DY, 139H, and SSLOW) were analyzed for their content of protease-resistant PrP(Sc) Our data show that these strains have different profiles of PrP deposition along the brain. These patterns of accumulation, which were independent of regional PrP(C) production, were not reproduced by in vitro replication when different brain regions were used as substrate for the misfolding-amplification reaction. On the contrary, our results show that in vitro replication efficiency depended exclusively on the amount of PrP(C) present in each part of the brain. Our results suggest that the variable regional distribution of PrP(Sc) in distinct strains is not determined by differences on prion formation, but on other factors or cellular pathways. Our findings may contribute to understand the molecular mechanisms of prion pathogenesis and strain diversity. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  18. Prion diseases and adult neurogenesis: how do prions counteract the brain's endogenous repair machinery?

    Science.gov (United States)

    Relaño-Ginés, Aroa; Lehmann, Sylvain; Crozet, Carole

    2014-01-01

    Scientific advances in stem cell biology and adult neurogenesis have raised the hope that neurodegenerative disorders could benefit from stem cell-based therapy. Adult neurogenesis might be part of the physiological regenerative process, however it might become impaired by the disease's mechanism and therefore contribute to neurodegeneration. In prion disorders this endogenous repair system has rarely been studied. Whether adult neurogenesis plays a role or not in brain repair or in the propagation of prion pathology remains unclear. We have recently investigated the status of adult neural stem cells isolated from prion-infected mice. We were able to show that neural stem cells accumulate and replicate prions thus resulting in an alteration of their neuronal destiny. We also reproduced these results in adult neural stem cells, which were infected in vitro. The fact that endogenous adult neurogenesis could be altered by the accumulation of misfolded prion protein represents another great challenge. Inhibiting prion propagation in these cells would thus help the endogenous neurogenesis to compensate for the injured neuronal system. Moreover, understanding the endogenous modulation of the neurogenesis system would help develop effective neural stem cell-based therapies.

  19. The Structural Stability of Wild-type Horse Prion Protein - Molecular Dynamics Studies

    OpenAIRE

    Zhang, Jiapu

    2011-01-01

    Prion diseases {\\it (e.g. Creutzfeldt-Jakob disease (CJD), variant CJD (vCJD), Gerstmann-Str$\\ddot{\\text{a}}$ussler-Scheinker syndrome (GSS), Fatal Familial Insomnia (FFI) and Kuru in humans, scrapie in sheep, bovine spongiform encephalopathy (BSE or `mad-cow' disease) and chronic wasting disease (CWD) in cattles)} are invariably fatal and highly infectious neurodegenerative diseases affecting humans and animals. However, by now there have not been some effective therapeutic approaches or med...

  20. Exploring physical and chemical factors influencing the properties of recombinant prion protein and the real-time quaking-induced conversion (RT-QuIC) assay.

    Science.gov (United States)

    Cheng, Keding; Sloan, Angela; Avery, Kristen M; Coulthart, Michael; Carpenter, Michael; Knox, J David

    2014-01-01

    Real-time quaking-induced conversion (RT-QuIC), a highly specific and sensitive assay able to detect low levels of the disease-inducing isoform of the prion protein (PrP(d)) in brain tissue biopsies and cerebral spinal fluid, has great potential to become a method for diagnosing prion disease ante mortem. In order to standardize the assay method for routine analysis, an understanding of how physical and chemical factors affect the stability of the recombinant prion protein (rPrP) substrate and the RT-QuIC assay's sensitivity, specificity, and reproducibility is required. In this study, using sporadic Creutzfeldt-Jakob Disease brain homogenate to seed the reactions and an in vitro-expressed recombinant prion protein, hamster rPrP, as the substrate, the following factors affecting the RT-QuIC assay were examined: salt and substrate concentrations, substrate storage, and pH. Results demonstrated that both the generation of the quality and quantities of rPrP substrate critical to the reaction, as well as the RT-QuIC reaction itself required strict adherence to specific physical and chemical conditions. Once optimized, the RT-QuIC assay was confirmed to be a very specific and sensitive assay method for sCJD detection. Findings in this study indicate that further optimization and standardization of RT-QuIC assay is required before it can be adopted as a routine diagnostic test.

  1. A closer look at prion strains: characterization and important implications.

    Science.gov (United States)

    Solforosi, Laura; Milani, Michela; Mancini, Nicasio; Clementi, Massimo; Burioni, Roberto

    2013-01-01

    Prions are infectious proteins that are responsible for transmissible spongiform encephalopathies (TSEs) and consist primarily of scrapie prion protein (PrP (Sc) ), a pathogenic isoform of the host-encoded cellular prion protein (PrP (C) ). The absence of nucleic acids as essential components of the infectious prions is the most striking feature associated to these diseases. Additionally, different prion strains have been isolated from animal diseases despite the lack of DNA or RNA molecules. Mounting evidence suggests that prion-strain-specific features segregate with different PrP (Sc) conformational and aggregation states. Strains are of practical relevance in prion diseases as they can drastically differ in many aspects, such as incubation period, PrP (Sc) biochemical profile (e.g., electrophoretic mobility and glycoform ratio) and distribution of brain lesions. Importantly, such different features are maintained after inoculation of a prion strain into genetically identical hosts and are relatively stable across serial passages. This review focuses on the characterization of prion strains and on the wide range of important implications that the study of prion strains involves.

  2. Association between rs6812193 polymorphism and sporadic Parkinson's disease susceptibility.

    Science.gov (United States)

    Huo, Qiang; Li, Tao; Zhao, Peiqing; Wang, Lianqing

    2015-08-01

    Recently, the association of a single nucleotide polymorphism rs6812193 C/T with sporadic Parkinson's disease (PD) susceptibility has been widely evaluated, but the results remained inconsistent. This association should be clarified because of the importance of it on human health and quality of life. We performed a comprehensive meta-analysis to evaluate the association between the rs6812193 polymorphism and sporadic PD. PubMed was used to retrieve articles published up to June 2014 for all studies evaluating the rs6812193 polymorphism and PD in humans. Ethnicity-specific subgroup analysis was also performed based on ethnicity susceptibility. A total of 17 independent study samples (15 Caucasians and 2 Asians) including 17,956 cases and 52,751 controls were used in the presented study. The MAFT (minor allele T frequency) in PD patients of European descent is obviously higher than Asian cases (p susceptibility among overall samples (OR 0.882, 95 % CI 0.856-0.908) and Caucasian population (OR 0.881, 95 % CI 0.856-0.907), but not in Asian samples (OR 0.918, 95 % CI 0.721-1.168). No evidence of publication bias was observed. Throughout our analysis, the rs6812193 polymorphism is significantly associated with sporadic PD susceptibility in Caucasian samples, and ethnicity might be the key point of inconsistency in rs6812193 studies. Further studies are warranted to re-examine the observed associations, especially in different ethnicities.

  3. Efficient prion disease transmission through common environmental materials.

    Science.gov (United States)

    Pritzkow, Sandra; Morales, Rodrigo; Lyon, Adam; Concha-Marambio, Luis; Urayama, Akihiko; Soto, Claudio

    2018-03-02

    Prion diseases are a group of fatal neurodegenerative diseases associated with a protein-based infectious agent, termed prion. Compelling evidence suggests that natural transmission of prion diseases is mediated by environmental contamination with infectious prions. We hypothesized that several natural and man-made materials, commonly found in the environments of wild and captive animals, can bind prions and may act as vectors for disease transmission. To test our hypothesis, we exposed surfaces composed of various common environmental materials ( i.e. wood, rocks, plastic, glass, cement, stainless steel, aluminum, and brass) to hamster-adapted 263K scrapie prions and studied their attachment and retention of infectivity in vitro and in vivo Our results indicated that these surfaces, with the sole exception of brass, efficiently bind, retain, and release prions. Prion replication was studied in vitro using the protein misfolding cyclic amplification technology, and infectivity of surface-bound prions was analyzed by intracerebrally challenging hamsters with contaminated implants. Our results revealed that virtually all prion-contaminated materials transmitted the disease at high rates. To investigate a more natural form of exposure to environmental contamination, we simply housed animals with large contaminated spheres made of the different materials under study. Strikingly, most of the hamsters developed classical clinical signs of prion disease and typical disease-associated brain changes. Our findings suggest that prion contamination of surfaces commonly present in the environment can be a source of disease transmission, thus expanding our understanding of the mechanisms for prion spreading in nature. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. MAJOR MOLECULAR GENETIC DRIVERS IN SPORADIC PRIMARY HYPERPARATHYROIDISM.

    Science.gov (United States)

    Arnold, Andrew

    2016-01-01

    Primary hyperparathyroidism is primarily due to a solitary parathyroid adenoma but multi-gland disease, parathyroid carcinoma, and ectopic parathyroid hormone production can occur. Although primary hyperparathyroidism mostly presents sporadically, strong familial predispositions also exist. Much is known about heritable genetic mutations responsible for these syndromes, including multiple endocrine neoplasia types 1 and 2A, hyperparathyroidism-jaw tumor syndrome, and familial hypocalciuric hypercalcemia. Acquired mutations in common sporadic hyperparathyroidism have also been discovered. Here we focus on the most common and well-established genetic drivers: 1) involvement of the oncogene cyclin D1 in human neoplasia was first established in parathyroid adenomas, followed by recognition of its importance in other tumor types including breast cancer and B-lymphoid malignancy; and 2) somatic mutation of the MEN1 gene, first identified as the source of pathogenic germline mutations in patients with familial endocrinopathies, is found in a substantial fraction of non-familial parathyroid adenomas.

  5. The prion protein and New World primate phylogeny

    Directory of Open Access Journals (Sweden)

    Igor Schneider

    2004-01-01

    Full Text Available The PrP C prion protein contains 250 amino acids with some variation among species and is expressed in several cell types. PrP C is converted to PrP Sc by a post-translational process in which it acquires amino acid sequences of three-dimensional conformation of beta-sheets. Variations in the prion protein gene were observed among 16 genera of New World primates (Platyrrhini, and resulted in amino acid substitutions when compared with the human sequence. Seven substitutions not yet described in the literature were found: W -> R at position 31 in Cebuella, T -> A at position 95 in Cacajao and Chiropotes, N-> S at position 100 in Brachyteles, L -> Q at position 130 in Leontopithecus (in the sequence responsible for generating the beta-sheet 1, D -> E at position 144 in Lagothrix (in the sequence responsible for the alpha-helix 1, D-> G at position 147 in Saguinus (also located in the alpha-helix 1 region, and M -> I at position 232 in Alouatta. The phylogenetic trees generated by parsimony, neighbor-joining and Bayesian analyses strongly support the monophyletic status of the platyrrhines, but did not resolve relationships among families. However, the results do corroborate previous findings, which indicate that the three platyrrhine families radiated rapidly from an ancient split.

  6. Prion protein β2-α2 loop conformational landscape.

    Science.gov (United States)

    Caldarulo, Enrico; Barducci, Alessandro; Wüthrich, Kurt; Parrinello, Michele

    2017-09-05

    In transmissible spongiform encephalopathies (TSEs), which are lethal neurodegenerative diseases that affect humans and a wide range of other mammalian species, the normal "cellular" prion protein ([Formula: see text]) is transformed into amyloid aggregates representing the "scrapie form" of the protein ([Formula: see text]). Continued research on this system is of keen interest, since new information on the physiological function of [Formula: see text] in healthy organisms is emerging, as well as new data on the mechanism of the transformation of [Formula: see text] to [Formula: see text] In this paper we used two different approaches: a combination of the well-tempered ensemble (WTE) and parallel tempering (PT) schemes and metadynamics (MetaD) to characterize the conformational free-energy surface of [Formula: see text] The focus of the data analysis was on an 11-residue polypeptide segment in mouse [Formula: see text](121-231) that includes the [Formula: see text]2-[Formula: see text]2 loop of residues 167-170, for which a correlation between structure and susceptibility to prion disease has previously been described. This study includes wild-type mouse [Formula: see text] and a variant with the single-residue replacement Y169A. The resulting detailed conformational landscapes complement in an integrative manner the available experimental data on [Formula: see text], providing quantitative insights into the nature of the structural transition-related function of the [Formula: see text]2-[Formula: see text]2 loop.

  7. Prion protein misfolding affects calcium homeostasis and sensitizes cells to endoplasmic reticulum stress.

    Directory of Open Access Journals (Sweden)

    Mauricio Torres

    2010-12-01

    Full Text Available Prion-related disorders (PrDs are fatal neurodegenerative disorders characterized by progressive neuronal impairment as well as the accumulation of an abnormally folded and protease resistant form of the cellular prion protein, termed PrP(RES. Altered endoplasmic reticulum (ER homeostasis is associated with the occurrence of neurodegeneration in sporadic, infectious and familial forms of PrDs. The ER operates as a major intracellular calcium store, playing a crucial role in pathological events related to neuronal dysfunction and death. Here we investigated the possible impact of PrP misfolding on ER calcium homeostasis in infectious and familial models of PrDs. Neuro2A cells chronically infected with scrapie prions showed decreased ER-calcium content that correlated with a stronger upregulation of UPR-inducible chaperones, and a higher sensitivity to ER stress-induced cell death. Overexpression of the calcium pump SERCA stimulated calcium release and increased the neurotoxicity observed after exposure of cells to brain-derived infectious PrP(RES. Furthermore, expression of PrP mutants that cause hereditary Creutzfeldt-Jakob disease or fatal familial insomnia led to accumulation of PrP(RES and their partial retention at the ER, associated with a drastic decrease of ER calcium content and higher susceptibility to ER stress. Finally, similar results were observed when a transmembrane form of PrP was expressed, which is proposed as a neurotoxic intermediate. Our results suggest that alterations in calcium homeostasis and increased susceptibility to ER stress are common pathological features of both infectious and familial PrD models.

  8. Distinct transmissibility features of TSE sources derived from ruminant prion diseases by the oral route in a transgenic mouse model (TgOvPrP4 overexpressing the ovine prion protein.

    Directory of Open Access Journals (Sweden)

    Jean-Noël Arsac

    Full Text Available Transmissible spongiform encephalopathies (TSEs are a group of fatal neurodegenerative diseases associated with a misfolded form of host-encoded prion protein (PrP. Some of them, such as classical bovine spongiform encephalopathy in cattle (BSE, transmissible mink encephalopathy (TME, kuru and variant Creutzfeldt-Jakob disease in humans, are acquired by the oral route exposure to infected tissues. We investigated the possible transmission by the oral route of a panel of strains derived from ruminant prion diseases in a transgenic mouse model (TgOvPrP4 overexpressing the ovine prion protein (A136R154Q171 under the control of the neuron-specific enolase promoter. Sources derived from Nor98, CH1641 or 87V scrapie sources, as well as sources derived from L-type BSE or cattle-passaged TME, failed to transmit by the oral route, whereas those derived from classical BSE and classical scrapie were successfully transmitted. Apart from a possible effect of passage history of the TSE agent in the inocula, this implied the occurrence of subtle molecular changes in the protease-resistant prion protein (PrPres following oral transmission that can raises concerns about our ability to correctly identify sheep that might be orally infected by the BSE agent in the field. Our results provide proof of principle that transgenic mouse models can be used to examine the transmissibility of TSE agents by the oral route, providing novel insights regarding the pathogenesis of prion diseases.

  9. Role of Prion Protein Aggregation in Neurotoxicity

    Directory of Open Access Journals (Sweden)

    Tullio Florio

    2012-07-01

    Full Text Available In several neurodegenerative diseases, such as Parkinson, Alzheimer’s, Huntington, and prion diseases, the deposition of aggregated misfolded proteins is believed to be responsible for the neurotoxicity that characterizes these diseases. Prion protein (PrP, the protein responsible of prion diseases, has been deeply studied for the peculiar feature of its misfolded oligomers that are able to propagate within affected brains, inducing the conversion of the natively folded PrP into the pathological conformation. In this review, we summarize the available experimental evidence concerning the relationship between aggregation status of misfolded PrP and neuronal death in the course of prion diseases. In particular, we describe the main findings resulting from the use of different synthetic (mainly PrP106-126 and recombinant PrP-derived peptides, as far as mechanisms of aggregation and amyloid formation, and how these different spatial conformations can affect neuronal death. In particular, most data support the involvement of non-fibrillar oligomers rather than actual amyloid fibers as the determinant of neuronal death.

  10. The structural core of prion disease

    NARCIS (Netherlands)

    Boshuizen, R.S.

    2010-01-01

    Transmissible spongiform encephalopathies (TSEs) or prion diseases are serious neurological ailments, in which the brain tissue deteriorates by progressive loss of brain cells which results in the loss of a wide variety of brain functions, including memory, speech and locomotion. Similar conditions

  11. Neuroinflammation in Alzheimer's disease and prion disease

    NARCIS (Netherlands)

    Eikelenboom, P.; Bate, C.; van Gool, W. A.; Hoozemans, J. J. M.; Rozemuller, J. M.; Veerhuis, R.; Williams, A.

    2002-01-01

    Alzheimer's disease (AD) and prion disease are characterized neuropathologically by extracellular deposits of Abeta and PrP amyloid fibrils, respectively. In both disorders, these cerebral amyloid deposits are co-localized with a broad variety of inflammation-related proteins (complement factors,

  12. Chronic wasting disease: Bambi vs. the prion

    Science.gov (United States)

    Chronic wasting disease (CWD) was first described in Colorado in 1967 and subsequently recognized as a prion disease in 1980. CWD has a long and asymptomatic incubation period (> 1 year) followed by a short disease course that ends in the death of the animal. There is no known treatment or cure for ...

  13. Prions: Protein Rebels with a Cause!

    Science.gov (United States)

    Marshall, Karen E.; Serpell, Louise C.

    2017-01-01

    Traditionally we consider infection to arise from viruses, bacteria and parasites. Prions are infectious proteins without any nucleic acids, and therefore do not represent living things. Despite this, they have the ability to replicate themselves and cause diseases such as mad cow disease (bovine spongiform encepthalopathy) and human…

  14. Prion Disease: Learn the Facts. Avoid Exposure.

    Centers for Disease Control (CDC) Podcasts

    2011-05-23

    This podcast discusses prion diseases and the risk of exposure associated with some common activities.  Created: 5/23/2011 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 5/23/2011.

  15. Live-cell FRET imaging reveals clustering of the prion protein at the cell surface induced by infectious prions.

    Science.gov (United States)

    Tavares, Evandro; Macedo, Joana A; Paulo, Pedro M R; Tavares, Catarina; Lopes, Carlos; Melo, Eduardo P

    2014-07-01

    Prion diseases are associated to the conversion of the prion protein into a misfolded pathological isoform. The mechanism of propagation of protein misfolding by protein templating remains largely unknown. Neuroblastoma cells were transfected with constructs of the prion protein fused to both CFP-GPI-anchored and to YFP-GPI-anchored and directed to its cell membrane location. Live-cell FRET imaging between the prion protein fused to CFP or YFP was measured giving consistent values of 10±2%. This result was confirmed by fluorescence lifetime imaging microscopy and indicates intermolecular interactions between neighbor prion proteins. In particular, considering that a maximum FRET efficiency of 17±2% was determined from a positive control consisting of a fusion CFP-YFP-GPI-anchored. A stable cell clone expressing the two fusions containing the prion protein was also selected to minimize cell-to-cell variability. In both, stable and transiently transfected cells, the FRET efficiency consistently increased in the presence of infectious prions - from 4±1% to 7±1% in the stable clone and from 10±2% to 16±1% in transiently transfected cells. These results clearly reflect an increased clustering of the prion protein on the membrane in the presence of infectious prions, which was not observed in negative control using constructs without the prion protein and upon addition of non-infected brain. Our data corroborates the recent view that the primary site for prion conversion is the cell membrane. Since our fluorescent cell clone is not susceptible to propagate infectivity, we hypothesize that the initial event of prion infectivity might be the clustering of the GPI-anchored prion protein. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Development of techniques in magnetic resonance and structural studies of the prion protein

    Energy Technology Data Exchange (ETDEWEB)

    Bitter, Hans-Marcus L. [Univ. of California, Berkeley, CA (United States)

    2000-07-01

    Magnetic resonance is the most powerful analytical tool used by chemists today. Its applications range from determining structures of large biomolecules to imaging of human brains. Nevertheless, magnetic resonance remains a relatively young field, in which many techniques are currently being developed that have broad applications. In this dissertation, two new techniques are presented, one that enables the determination of torsion angles in solid-state peptides and proteins, and another that involves imaging of heterogenous materials at ultra-low magnetic fields. In addition, structural studies of the prion protein via solid-state NMR are described. More specifically, work is presented in which the dependence of chemical shifts on local molecular structure is used to predict chemical shift tensors in solid-state peptides with theoretical ab initio surfaces. These predictions are then used to determine the backbone dihedral angles in peptides. This method utilizes the theoretical chemicalshift tensors and experimentally determined chemical-shift anisotropies (CSAs) to predict the backbone and side chain torsion angles in alanine, leucine, and valine residues. Additionally, structural studies of prion protein fragments are described in which conformationally-dependent chemical-shift measurements were made to gain insight into the structural differences between the various conformational states of the prion protein. These studies are of biological and pathological interest since conformational changes in the prion protein are believed to cause prion diseases. Finally, an ultra-low field magnetic resonance imaging technique is described that enables imaging and characterization of heterogeneous and porous media. The notion of imaging gases at ultra-low fields would appear to be very difficult due to the prohibitively low polarization and spin densities as well as the low sensitivities of conventional Faraday coil detectors. However, Chapter 5 describes how gas imaging

  17. Saccharomyces cerevisiae: a sexy yeast with a prion problem.

    Science.gov (United States)

    Kelly, Amy C; Wickner, Reed B

    2013-01-01

    Yeast prions are infectious proteins that spread exclusively by mating. The frequency of prions in the wild therefore largely reflects the rate of spread by mating counterbalanced by prion growth slowing effects in the host. We recently showed that the frequency of outcross mating is about 1% of mitotic doublings with 23-46% of total matings being outcrosses. These findings imply that even the mildest forms of the [PSI+], [URE3] and [PIN+] prions impart > 1% growth/survival detriment on their hosts. Our estimate of outcrossing suggests that Saccharomyces cerevisiae is far more sexual than previously thought and would therefore be more responsive to the adaptive effects of natural selection compared with a strictly asexual yeast. Further, given its large effective population size, a growth/survival detriment of > 1% for yeast prions should strongly select against prion-infected strains in wild populations of Saccharomyces cerevisiae.

  18. Reduced response of splenocytes after mitogen-stimulation in the prion protein (PrP) gene-deficient mouse: PrPLP/Doppel production and cerebral degeneration

    International Nuclear Information System (INIS)

    Kim, Chi-Kyeong; Hirose, Yuko; Sakudo, Akikazu; Takeyama, Natsumi; Kang, Chung-Boo; Taniuchi, Yojiro; Matsumoto, Yoshitsugu; Itohara, Shigeyoshi; Sakaguchi, Suehiro; Onodera, Takashi

    2007-01-01

    Splenocytes of wild-type (Prnp +/+ ) and prion protein gene-deficient (Prnp -/- ) mice were treated with various activation stimuli such as T cell mitogen concanavalin A (ConA), phorbol 12-myristate 13-acetate (PMA) + ionomycin (Io), or B cell mitogen lipopolysaccharide (LPS). Cellular prion protein (PrP C ) expression was enhanced following ConA stimulation, but not PMA + Io or LPS in Prnp +/+ splenocytes. Rikn Prnp -/- splenocytes elicited lower cell proliferations than Prnp +/+ or Zrch I Prnp -/- splenocytes after LPS stimulation and showed sporadic nerve cells in the cerebral cortex and deeper structure. Around the degenerated nerve cells, mild vacuolation in the neuropil was observed. This neural alteration correlated well to the suppressed response of B cells in the spleen. The finding that discrete lesions within the central nervous systems induced marked modulation of immune function probably indicates the existence of a delicately balanced neural-endocrine network by PrP C and PrPLP/Doppel

  19. Anti-prion activity of Brilliant Blue G.

    Directory of Open Access Journals (Sweden)

    Yoshifumi Iwamaru

    Full Text Available BACKGROUND: Prion diseases are fatal neurodegenerative disorders with no effective therapy currently available. Accumulating evidence has implicated over-activation of P2X7 ionotropic purinergic receptor (P2X7R in the progression of neuronal loss in several neurodegenerative diseases. This has led to the speculation that simultaneous blockade of this receptor and prion replication can be an effective therapeutic strategy for prion diseases. We have focused on Brilliant Blue G (BBG, a well-known P2X7R antagonist, possessing a chemical structure expected to confer anti-prion activity and examined its inhibitory effect on the accumulation of pathogenic isoforms of prion protein (PrPres in a cellular and a mouse model of prion disease in order to determine its therapeutic potential. PRINCIPAL FINDINGS: BBG prevented PrPres accumulation in infected MG20 microglial and N2a neural cells at 50% inhibitory concentrations of 14.6 and 3.2 µM, respectively. Administration of BBG in vivo also reduced PrPres accumulation in the brains of mice with prion disease. However, it did not appear to alleviate the disease progression compared to the vehicle-treated controls, implying a complex role of P2X7R on the neuronal degeneration in prion diseases. SIGNIFICANCE: These results provide novel insights into the pathophysiology of prion diseases and have important implications for the treatment.

  20. Soluble polymorphic bank vole prion proteins induced by co-expression of quiescin sulfhydryl oxidase in E. coli and their aggregation behaviors.

    Science.gov (United States)

    Abskharon, Romany; Dang, Johnny; Elfarash, Ameer; Wang, Zerui; Shen, Pingping; Zou, Lewis S; Hassan, Sedky; Wang, Fei; Fujioka, Hisashi; Steyaert, Jan; Mulaj, Mentor; Surewicz, Witold K; Castilla, Joaquín; Wohlkonig, Alexandre; Zou, Wen-Quan

    2017-10-04

    The infectious prion protein (PrP Sc or prion) is derived from its cellular form (PrP C ) through a conformational transition in animal and human prion diseases. Studies have shown that the interspecies conversion of PrP C to PrP Sc is largely swayed by species barriers, which is mainly deciphered by the sequence and conformation of the proteins among species. However, the bank vole PrP C (BVPrP) is highly susceptible to PrP Sc from different species. Transgenic mice expressing BVPrP with the polymorphic isoleucine (109I) but methionine (109M) at residue 109 spontaneously develop prion disease. To explore the mechanism underlying the unique susceptibility and convertibility, we generated soluble BVPrP by co-expression of BVPrP with Quiescin sulfhydryl oxidase (QSOX) in Escherichia coli. Interestingly, rBVPrP-109M and rBVPrP-109I exhibited distinct seeded aggregation pathways and aggregate morphologies upon seeding of mouse recombinant PrP fibrils, as monitored by thioflavin T fluorescence and electron microscopy. Moreover, they displayed different aggregation behaviors induced by seeding of hamster and mouse prion strains under real-time quaking-induced conversion. Our results suggest that QSOX facilitates the formation of soluble prion protein and provide further evidence that the polymorphism at residue 109 of QSOX-induced BVPrP may be a determinant in mediating its distinct convertibility and susceptibility.

  1. The effects of glutamine/asparagine content on aggregation and heterologous prion induction by yeast prion-like domains.

    Science.gov (United States)

    Shattuck, Jenifer E; Waechter, Aubrey C; Ross, Eric D

    2017-07-04

    Prion-like domains are low complexity, intrinsically disordered domains that compositionally resemble yeast prion domains. Many prion-like domains are involved in the formation of either functional or pathogenic protein aggregates. These aggregates range from highly dynamic liquid droplets to highly ordered detergent-insoluble amyloid-like aggregates. To better understand the amino acid sequence features that promote conversion to stable, detergent-insoluble aggregates, we used the prediction algorithm PAPA to identify predicted aggregation-prone prion-like domains with a range of compositions. While almost all of the predicted aggregation-prone domains formed foci when expressed in cells, the ability to form the detergent-insoluble aggregates was highly correlated with glutamine/asparagine (Q/N) content, suggesting that high Q/N content may specifically promote conversion to the amyloid state in vivo. We then used this data set to examine cross-seeding between prion-like proteins. The prion protein Sup35 requires the presence of a second prion, [PIN + ], to efficiently form prions, but this requirement can be circumvented by the expression of various Q/N-rich protein fragments. Interestingly, almost all of the Q/N-rich domains that formed SDS-insoluble aggregates were able to promote prion formation by Sup35, highlighting the highly promiscuous nature of these interactions.

  2. Prion-Specific Antibodies Produced in Wild-Type Mice

    DEFF Research Database (Denmark)

    Heegaard, Peter M. H.; Bergström, Ann-Louise; Andersen, Heidi Gertz

    2015-01-01

    Peptide-specific antibodies produced against synthetic peptides are of high value in probing protein structure and function, especially when working with challenging proteins, including not readily available, non-immunogenic, toxic, and/or pathogenic proteins. Here, we present a straightforward...... method for production of mouse monoclonal antibodies (MAbs) against peptides representing two sites of interest in the bovine prion protein (boPrP), the causative agent of bovine spongiform encephalopathy ("mad cow disease") and new variant Creutzfeldt-Jakob's disease (CJD) in humans, as well......-peptide antibodies, even against peptides very homologous to murine protein sequences. In general, using the strategies described here for selecting, synthesizing, and conjugating peptides and immunizing 4-5 mice with 2-3 different peptides, high-titered antibodies reacting with the target protein are routinely...

  3. Involvement of Endogenous Retroviruses in Prion Diseases

    Directory of Open Access Journals (Sweden)

    Yong-Sun Kim

    2013-08-01

    Full Text Available For millions of years, vertebrates have been continuously exposed to infection by retroviruses. Ancient retroviral infection of germline cells resulted in the formation and accumulation of inherited retrovirus sequences in host genomes. These inherited retroviruses are referred to as endogenous retroviruses (ERVs, and recent estimates have revealed that a significant portion of animal genomes is made up of ERVs. Although various host factors have suppressed ERV activation, both positive and negative functions have been reported for some ERVs in normal and abnormal physiological conditions, such as in disease states. Similar to other complex diseases, ERV activation has been observed in prion diseases, and this review will discuss the potential involvement of ERVs in prion diseases.

  4. Methods and Protocols for Developing Prion Vaccines.

    Science.gov (United States)

    Marciniuk, Kristen; Taschuk, Ryan; Napper, Scott

    2016-01-01

    Prion diseases denote a distinct form of infectivity that is based in the misfolding of a self-protein (PrP(C)) into a pathological, infectious conformation (PrP(Sc)). Efforts to develop vaccines for prion diseases have been complicated by the potential dangers that are associated with induction of immune responses against a self-protein. As a consequence, there is considerable appeal for vaccines that specifically target the misfolded prion conformation. Such conformation-specific immunotherapy is made possible through the identification of vaccine targets (epitopes) that are exclusively presented as a consequence of misfolding. An immune response directed against these targets, termed disease-specific epitopes (DSEs), has the potential to spare the function of the native form of the protein while clearing, or neutralizing, the infectious isomer. Although identification of DSEs represents a critical first step in the induction of conformation-specific immune responses, substantial efforts are required to translate these targets into functional vaccines. Due to the poor immunogenicity that is inherent to self-proteins, and that is often associated with short peptides, substantial efforts are required to overcome tolerance-to-self and maximize the resultant immune response following DSE-based immunization. This often includes optimization of target sequences in terms of immunogenicity and development of effective formulation and delivery strategies for the associated peptides. Further, these vaccines must satisfy additional criteria from perspectives of specificity (PrP(C) vs. PrP(Sc)) and safety (antibody-induced template-driven misfolding of PrP(C)). The emphasis of this report is on the steps required to translate DSEs into prion vaccines and subsequent evaluation of the resulting immune responses.

  5. Mutation directional selection sheds light on prion pathogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Liang [Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Shandong University of Technology, Zibo 255049 (China); Ji, Hong-Fang, E-mail: jhf@sdut.edu.cn [Shandong Provincial Research Center for Bioinformatic Engineering and Technique, Shandong University of Technology, Zibo 255049 (China)

    2011-07-01

    Highlights: {yields} Most pathogenic mutations possess strong directional selection, i.e., enhancing hydrophobicity or decreasing negative and increasing positive charge. {yields} Mutation-induced changes may strengthen the interactions between PrP and facilitating factors. {yields} The findings also have significant implications for exploring potential regions involved in the conformational transition from PrP{sup C} to PrP{sup Sc}. -- Abstract: As mutations in the PRNP gene account for human hereditary prion diseases (PrDs), it is crucial to elucidating how these mutations affect the central pathogenic conformational transition of normal cellular prion protein (PrP{sup C}) to abnormal scrapie isoform (PrP{sup Sc}). Many studies proposed that these pathogenic mutations may make PrP more susceptible to conformational change through altering its structure stability. By evaluating the most recent observations regarding pathogenic mutations, it was found that the pathogenic mutations do not exert a uniform effect on the thermodynamic stability of the human PrP's structure. Through analyzing the reported PrDs-related mutations, we found that 25 out of 27 mutations possess strong directional selection, i.e., enhancing hydrophobicity or decreasing negative and increasing positive charge. Based on the triggering role reported by previous studies of facilitating factors in PrP{sup C} conversion, e.g., lipid and polyanion, we proposed that the mutation-induced changes may strengthen the interaction between PrP and facilitating factors, which will accelerate PrP conversion and cause PrDs.

  6. Intraperitoneal Infection of Wild-Type Mice with Synthetically Generated Mammalian Prion.

    Directory of Open Access Journals (Sweden)

    Xinhe Wang

    2015-07-01

    Full Text Available The prion hypothesis postulates that the infectious agent in transmissible spongiform encephalopathies (TSEs is an unorthodox protein conformation based agent. Recent successes in generating mammalian prions in vitro with bacterially expressed recombinant prion protein provide strong support for the hypothesis. However, whether the pathogenic properties of synthetically generated prion (rec-Prion recapitulate those of naturally occurring prions remains unresolved. Using end-point titration assay, we showed that the in vitro prepared rec-Prions have infectious titers of around 104 LD50/μg. In addition, intraperitoneal (i.p. inoculation of wild-type mice with rec-Prion caused prion disease with an average survival time of 210-220 days post inoculation. Detailed pathological analyses revealed that the nature of rec-Prion induced lesions, including spongiform change, disease specific prion protein accumulation (PrP-d and the PrP-d dissemination amongst lymphoid and peripheral nervous system tissues, the route and mechanisms of neuroinvasion were all typical of classical rodent prions. Our results revealed that, similar to naturally occurring prions, the rec-Prion has a titratable infectivity and is capable of causing prion disease via routes other than direct intra-cerebral challenge. More importantly, our results established that the rec-Prion caused disease is pathogenically and pathologically identical to naturally occurring contagious TSEs, supporting the concept that a conformationally altered protein agent is responsible for the infectivity in TSEs.

  7. Sporadic simple groups and quotient singularities

    International Nuclear Information System (INIS)

    Cheltsov, I A; Shramov, C A

    2013-01-01

    We show that if a faithful irreducible representation of a central extension of a sporadic simple group with centre contained in the commutator subgroup gives rise to an exceptional (resp. weakly exceptional but not exceptional) quotient singularity, then that simple group is the Hall-Janko group (resp. the Suzuki group)

  8. Resistance of soil-bound prions to rumen digestion.

    Directory of Open Access Journals (Sweden)

    Samuel E Saunders

    Full Text Available Before prion uptake and infection can occur in the lower gastrointestinal system, ingested prions are subjected to anaerobic digestion in the rumen of cervids and bovids. The susceptibility of soil-bound prions to rumen digestion has not been evaluated previously. In this study, prions from infectious brain homogenates as well as prions bound to a range of soils and soil minerals were subjected to in vitro rumen digestion, and changes in PrP levels were measured via western blot. Binding to clay appeared to protect noninfectious hamster PrP(c from complete digestion, while both unbound and soil-bound infectious PrP(Sc proved highly resistant to rumen digestion. In addition, no change in intracerebral incubation period was observed following active rumen digestion of unbound hamster HY TME prions and HY TME prions bound to a silty clay loam soil. These results demonstrate that both unbound and soil-bound prions readily survive rumen digestion without a reduction in infectivity, further supporting the potential for soil-mediated transmission of chronic wasting disease (CWD and scrapie in the environment.

  9. Disturbed vesicular trafficking of membrane proteins in prion disease.

    Science.gov (United States)

    Uchiyama, Keiji; Miyata, Hironori; Sakaguchi, Suehiro

    2013-01-01

    The pathogenic mechanism of prion diseases remains unknown. We recently reported that prion infection disturbs post-Golgi trafficking of certain types of membrane proteins to the cell surface, resulting in reduced surface expression of membrane proteins and abrogating the signal from the proteins. The surface expression of the membrane proteins was reduced in the brains of mice inoculated with prions, well before abnormal symptoms became evident. Prions or pathogenic prion proteins were mainly detected in endosomal compartments, being particularly abundant in recycling endosomes. Some newly synthesized membrane proteins are delivered to the surface from the Golgi apparatus through recycling endosomes, and some endocytosed membrane proteins are delivered back to the surface through recycling endosomes. These results suggest that prions might cause neuronal dysfunctions and cell loss by disturbing post-Golgi trafficking of membrane proteins via accumulation in recycling endosomes. Interestingly, it was recently shown that delivery of a calcium channel protein to the cell surface was impaired and its function was abrogated in a mouse model of hereditary prion disease. Taken together, these results suggest that impaired delivery of membrane proteins to the cell surface is a common pathogenic event in acquired and hereditary prion diseases.

  10. Selfish prion of Rnq1 mutant in yeast.

    Science.gov (United States)

    Kurahashi, Hiroshi; Shibata, Shoichiro; Ishiwata, Masao; Nakamura, Yoshikazu

    2009-05-01

    [PIN(+)] is a prion form of Rnq1 in Saccharomyces cerevisiae and is necessary for the de novo induction of a second prion, [PSI(+)]. We previously isolated a truncated form of Rnq1, named Rnq1Delta100, as a [PSI(+)]-eliminating factor in S. cerevisiae. Rnq1Delta100 deletes the N-terminal non-prion domain of Rnq1, and eliminates [PSI(+)] in [PIN(+)] yeast. Here we found that [PIN(+)] is transmissible to Rnq1Delta100 in the absence of full-length Rnq1, forming a novel prion variant [RNQ1Delta100(+)]. [RNQ1Delta100(+)] has similar [PIN(+)] properties as it stimulates the de novo induction of [PSI(+)] and is eliminated by the null hsp104Delta mutation, but not by Hsp104 overproduction. In contrast, [RNQ1Delta100(+)] inherits the inhibitory activity and hampers the maintenance of [PSI(+)] though less efficiently than [PIN(+)] made of Rnq1-Rnq1Delta100 co-aggregates. Interestingly, [RNQ1Delta100(+)] prion was eliminated by de novo [PSI(+)] induction. Thus, the [RNQ1Delta100(+)] prion demonstrates selfish activity to eliminate a heterologous prion in S. cerevisiae, showing the first instance of a selfish prion variant in living organisms.

  11. Resistance of Soil-Bound Prions to Rumen Digestion

    Science.gov (United States)

    Saunders, Samuel E.; Bartelt-Hunt, Shannon L.; Bartz, Jason C.

    2012-01-01

    Before prion uptake and infection can occur in the lower gastrointestinal system, ingested prions are subjected to anaerobic digestion in the rumen of cervids and bovids. The susceptibility of soil-bound prions to rumen digestion has not been evaluated previously. In this study, prions from infectious brain homogenates as well as prions bound to a range of soils and soil minerals were subjected to in vitro rumen digestion, and changes in PrP levels were measured via western blot. Binding to clay appeared to protect noninfectious hamster PrPc from complete digestion, while both unbound and soil-bound infectious PrPSc proved highly resistant to rumen digestion. In addition, no change in intracerebral incubation period was observed following active rumen digestion of unbound hamster HY TME prions and HY TME prions bound to a silty clay loam soil. These results demonstrate that both unbound and soil-bound prions readily survive rumen digestion without a reduction in infectivity, further supporting the potential for soil-mediated transmission of chronic wasting disease (CWD) and scrapie in the environment. PMID:22937149

  12. Do prion protein gene polymorphisms induce apoptosis in non ...

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... Genetic variations such as single nucleotide polymorphisms (SNPs) in prion protein coding gene, Prnp, greatly affect susceptibility to prion diseases in mammals. Here, the coding region of Prnp was screened for polymorphisms in redeared turtle, Trachemys scripta. Four polymorphisms, L203V, N205I, ...

  13. Chronic wasting disease prion infection of differentiated neurospheres.

    Science.gov (United States)

    Iwamaru, Yoshifumi; Mathiason, Candace K; Telling, Glenn C; Hoover, Edward A

    2017-07-04

    A possible strategy to develop more diverse cell culture systems permissive to infection with naturally occurring prions is to exploit culture of neurospheres from transgenic mice expressing the normal prion protein (PrP) of the native host species. Accordingly, we developed differentiated neurosphere cultures from the cervid PrP-expressing mice to investigate whether this in vitro system would support replication of non-adapted cervid-origin chronic wasting disease (CWD) prions. Here we report the successful amplification of disease-associated PrP in differentiated neurosphere cultures within 3 weeks after exposure to CWD prions from both white-tailed deer or elk. This neurosphere culture system provides a new in vitro tool that can be used to assess non-adapted CWD prion propagation and transmission.

  14. Aβ seeds and prions: How close the fit?

    Science.gov (United States)

    Rasmussen, Jay; Jucker, Mathias; Walker, Lary C

    2017-07-04

    The prion paradigm is increasingly invoked to explain the molecular pathogenesis of neurodegenerative diseases involving the misfolding and aggregation of proteins other than the prion protein (PrP). Extensive evidence from in vitro and in vivo studies indicates that misfolded and aggregated Aβ peptide, which is the probable molecular trigger for Alzheimer's disease, manifests all of the key characteristics of canonical mammalian prions. These features include a β-sheet rich architecture, tendency to polymerize into amyloid, templated corruption of like protein molecules, ability to form structurally and functionally variant strains, systematic spread by neuronal transport, and resistance to inactivation by heat and formaldehyde. In addition to Aβ, a growing body of research supports the view that the prion-like molecular transformation of specific proteins drives the onset and course of a remarkable variety of clinicopathologically diverse diseases. As such, the expanded prion paradigm could conceptually unify fundamental and translational investigations of these disorders.

  15. Truncated forms of the prion protein PrP demonstrate the need for complexity in prion structure

    Energy Technology Data Exchange (ETDEWEB)

    Wan, William; Stöhr, Jan; Kendall, Amy; Stubbs, Gerald

    2015-09-01

    Self-propagation of aberrant protein folds is the defining characteristic of prions. Knowing the structural basis of self-propagation is essential to understanding prions and their related diseases. Prion rods are amyloid fibrils, but not all amyloids are prions. Prions have been remarkably intractable to structural studies, so many investigators have preferred to work with peptide fragments, particularly in the case of the mammalian prion protein PrP. We compared the structures of a number of fragments of PrP by X-ray fiber diffraction, and found that although all of the peptides adopted amyloid conformations, only the larger fragments adopted conformations that modeled the complexity of self-propagating prions, and even these fragments did not always adopt the PrP structure. It appears that the relatively complex structure of the prion form of PrP is not accessible to short model peptides, and that self-propagation may be tied to a level of structural complexity unobtainable in simple model systems. The larger fragments of PrP, however, are useful to illustrate the phenomenon of deformed templating (heterogeneous seeding), which has important biological consequences.

  16. Biological and biochemical characterization of mice expressing prion protein devoid of the octapeptide repeat region after infection with prions.

    Science.gov (United States)

    Yamaguchi, Yoshitaka; Miyata, Hironori; Uchiyama, Keiji; Ootsuyama, Akira; Inubushi, Sachiko; Mori, Tsuyoshi; Muramatsu, Naomi; Katamine, Shigeru; Sakaguchi, Suehiro

    2012-01-01

    Accumulating lines of evidence indicate that the N-terminal domain of prion protein (PrP) is involved in prion susceptibility in mice. In this study, to investigate the role of the octapeptide repeat (OR) region alone in the N-terminal domain for the susceptibility and pathogenesis of prion disease, we intracerebrally inoculated RML scrapie prions into tg(PrPΔOR)/Prnp(0/0) mice, which express mouse PrP missing only the OR region on the PrP-null background. Incubation times of these mice were not extended. Protease-resistant PrPΔOR, or PrP(Sc)ΔOR, was easily detectable but lower in the brains of these mice, compared to that in control wild-type mice. Consistently, prion titers were slightly lower and astrogliosis was milder in their brains. However, in their spinal cords, PrP(Sc)ΔOR and prion titers were abundant and astrogliosis was as strong as in control wild-type mice. These results indicate that the role of the OR region in prion susceptibility and pathogenesis of the disease is limited. We also found that the PrP(Sc)ΔOR, including the pre-OR residues 23-50, was unusually protease-resistant, indicating that deletion of the OR region could cause structural changes to the pre-OR region upon prion infection, leading to formation of a protease-resistant structure for the pre-OR region.

  17. Truncated forms of the prion protein PrP demonstrate the need for complexity in prion structure.

    Science.gov (United States)

    Wan, William; Stöhr, Jan; Kendall, Amy; Stubbs, Gerald

    2015-01-01

    Self-propagation of aberrant protein folds is the defining characteristic of prions. Knowing the structural basis of self-propagation is essential to understanding prions and their related diseases. Prion rods are amyloid fibrils, but not all amyloids are prions. Prions have been remarkably intractable to structural studies, so many investigators have preferred to work with peptide fragments, particularly in the case of the mammalian prion protein PrP. We compared the structures of a number of fragments of PrP by X-ray fiber diffraction, and found that although all of the peptides adopted amyloid conformations, only the larger fragments adopted conformations that modeled the complexity of self-propagating prions, and even these fragments did not always adopt the PrP structure. It appears that the relatively complex structure of the prion form of PrP is not accessible to short model peptides, and that self-propagation may be tied to a level of structural complexity unobtainable in simple model systems. The larger fragments of PrP, however, are useful to illustrate the phenomenon of deformed templating (heterogeneous seeding), which has important biological consequences.

  18. Prion Replication Elicits Cytopathic Changes in Differentiated Neurosphere Cultures

    Science.gov (United States)

    Iwamaru, Yoshifumi; Takenouchi, Takato; Imamura, Morikazu; Shimizu, Yoshihisa; Miyazawa, Kohtaro; Mohri, Shirou; Yokoyama, Takashi

    2013-01-01

    The molecular mechanisms of prion-induced cytotoxicity remain largely obscure. Currently, only a few cell culture models have exhibited the cytopathic changes associated with prion infection. In this study, we introduced a cell culture model based on differentiated neurosphere cultures isolated from the brains of neonatal prion protein (PrP)-null mice and transgenic mice expressing murine PrP (dNP0 and dNP20 cultures). Upon exposure to mouse Chandler prions, dNP20 cultures supported the de novo formation of abnormal PrP and the resulting infectivity, as assessed by bioassays. Furthermore, this culture was susceptible to various prion strains, including mouse-adapted scrapie, bovine spongiform encephalopathy, and Gerstmann-Sträussler-Scheinker syndrome prions. Importantly, a subset of the cells in the infected culture that was mainly composed of astrocyte lineage cells consistently displayed late-occurring, progressive signs of cytotoxicity as evidenced by morphological alterations, decreased cell viability, and increased lactate dehydrogenase release. These signs of cytotoxicity were not observed in infected dNP0 cultures, suggesting the requirement of endogenous PrP expression for prion-induced cytotoxicity. Degenerated cells positive for glial fibrillary acidic protein accumulated abnormal PrP and exhibited features of apoptotic death as assessed by active caspase-3 and terminal deoxynucleotidyltransferase nick-end staining. Furthermore, caspase inhibition provided partial protection from prion-mediated cell death. These results suggest that differentiated neurosphere cultures can provide an in vitro bioassay for mouse prions and permit the study of the molecular basis for prion-induced cytotoxicity at the cellular level. PMID:23740992

  19. Rapid antemortem detection of CWD prions in deer saliva.

    Directory of Open Access Journals (Sweden)

    Davin M Henderson

    Full Text Available Chronic wasting disease (CWD is an efficiently transmitted prion disease of cervids, now identified in 22 United States, 2 Canadian provinces and Korea. One hallmark of CWD is the shedding of infectious prions in saliva, as demonstrated by bioassay in deer. It is also clear that the concentration of prions in saliva, blood, urine and feces is much lower than in the nervous system or lymphoid tissues. Rapid in vitro detection of CWD (and other prions in body fluids and excreta has been problematic due to the sensitivity limits of direct assays (western blotting, ELISA and the presence of inhibitors in these complex biological materials that hamper detection. Here we use real-time quaking induced conversion (RT-QuIC to demonstrate CWD prions in both diluted and prion-enriched saliva samples from asymptomatic and symptomatic white-tailed deer. CWD prions were detected in 14 of 24 (58.3% diluted saliva samples from CWD-exposed white-tailed deer, including 9 of 14 asymptomatic animals (64.2%. In addition, a phosphotungstic acid enrichment enhanced the RT-QuIC assay sensitivity, enabling detection in 19 of 24 (79.1% of the above saliva samples. Bioassay in Tg[CerPrP] mice confirmed the presence of infectious prions in 2 of 2 RT-QuIC-positive saliva samples so examined. The modified RT-QuIC analysis described represents a non-invasive, rapid ante-mortem detection of prions in complex biologic fluids, excreta, or environmental samples as well as a tool for exploring prion trafficking, peripheralization, and dissemination.

  20. Prion Amplification and Hierarchical Bayesian Modeling Refine Detection of Prion Infection

    Science.gov (United States)

    Wyckoff, A. Christy; Galloway, Nathan; Meyerett-Reid, Crystal; Powers, Jenny; Spraker, Terry; Monello, Ryan J.; Pulford, Bruce; Wild, Margaret; Antolin, Michael; Vercauteren, Kurt; Zabel, Mark

    2015-02-01

    Prions are unique infectious agents that replicate without a genome and cause neurodegenerative diseases that include chronic wasting disease (CWD) of cervids. Immunohistochemistry (IHC) is currently considered the gold standard for diagnosis of a prion infection but may be insensitive to early or sub-clinical CWD that are important to understanding CWD transmission and ecology. We assessed the potential of serial protein misfolding cyclic amplification (sPMCA) to improve detection of CWD prior to the onset of clinical signs. We analyzed tissue samples from free-ranging Rocky Mountain elk (Cervus elaphus nelsoni) and used hierarchical Bayesian analysis to estimate the specificity and sensitivity of IHC and sPMCA conditional on simultaneously estimated disease states. Sensitivity estimates were higher for sPMCA (99.51%, credible interval (CI) 97.15-100%) than IHC of obex (brain stem, 76.56%, CI 57.00-91.46%) or retropharyngeal lymph node (90.06%, CI 74.13-98.70%) tissues, or both (98.99%, CI 90.01-100%). Our hierarchical Bayesian model predicts the prevalence of prion infection in this elk population to be 18.90% (CI 15.50-32.72%), compared to previous estimates of 12.90%. Our data reveal a previously unidentified sub-clinical prion-positive portion of the elk population that could represent silent carriers capable of significantly impacting CWD ecology.

  1. Prion amplification and hierarchical Bayesian modeling refine detection of prion infection.

    Science.gov (United States)

    Wyckoff, A Christy; Galloway, Nathan; Meyerett-Reid, Crystal; Powers, Jenny; Spraker, Terry; Monello, Ryan J; Pulford, Bruce; Wild, Margaret; Antolin, Michael; VerCauteren, Kurt; Zabel, Mark

    2015-02-10

    Prions are unique infectious agents that replicate without a genome and cause neurodegenerative diseases that include chronic wasting disease (CWD) of cervids. Immunohistochemistry (IHC) is currently considered the gold standard for diagnosis of a prion infection but may be insensitive to early or sub-clinical CWD that are important to understanding CWD transmission and ecology. We assessed the potential of serial protein misfolding cyclic amplification (sPMCA) to improve detection of CWD prior to the onset of clinical signs. We analyzed tissue samples from free-ranging Rocky Mountain elk (Cervus elaphus nelsoni) and used hierarchical Bayesian analysis to estimate the specificity and sensitivity of IHC and sPMCA conditional on simultaneously estimated disease states. Sensitivity estimates were higher for sPMCA (99.51%, credible interval (CI) 97.15-100%) than IHC of obex (brain stem, 76.56%, CI 57.00-91.46%) or retropharyngeal lymph node (90.06%, CI 74.13-98.70%) tissues, or both (98.99%, CI 90.01-100%). Our hierarchical Bayesian model predicts the prevalence of prion infection in this elk population to be 18.90% (CI 15.50-32.72%), compared to previous estimates of 12.90%. Our data reveal a previously unidentified sub-clinical prion-positive portion of the elk population that could represent silent carriers capable of significantly impacting CWD ecology.

  2. Sporadic Creutzfeldt-Jakob Disease (sCJD)

    Centers for Disease Control (CDC) Podcasts

    In this podcast, Dr. Lynne Sehulster discusses Creutzfeldt-Jakob disease, a rare neurodegenerative disease. This disease is caused by a pathological accumulation in the brain of an abnormal protein known as prions.

  3. [Perioperative considerations for performing a brain biopsy on a patient with subtype VV2 sporadic Creutzfeldt-Jakob disease].

    Science.gov (United States)

    Guerrero-Domínguez, R; Rubio-Romero, R; González-González, G; Jiménez, I

    2015-04-01

    Creutzfeldt-Jakob disease (CJD) is the most common transmissible spongiform encephalopathy. It is an infectious, progressive, degenerative neurological disorder, with a presumably long incubation period, but a rapid fatal course. CJD is transmitted by a proteinaceous infectious agent, or «prion». Because the prions are difficult to eradicate and are resistant to the currently used sterilization methods, special precautions must be taken with all surgical instruments. It is recommended the single-use equipment, destruction of contaminated equipment, decontamination of reusable instruments, use of protective clothing, and storing and quarantining surgical instruments. The single-use equipment and some tissues and body fluids from the patient with CJD are highly infectious and must be incinerated. We report a case of a patient who had undergone brain biopsy for suspected of CJD, being confirmed to have sporadic CJD. Specific preventive measures were taken to reduce the risk of transmission to healthcare workers. Copyright © 2014 Sociedad Española de Anestesiología, Reanimación y Terapéutica del Dolor. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Prions, From Structure to Epigenetics and Neuronal Functions

    Science.gov (United States)

    Lindquist, Susan

    2012-02-01

    Prions are a unique type of protein that can misfold and convert other proteins to the same shape. The well-characterized yeast prion [PSI+] is formed from an inactive amyloid fiber conformation of the translation-termination factor, Sup35. This altered conformation is passed from mother cells to daughters, acting as a template to perpetuate the prion state and providing a mechanism of protein-based inheritance. We employed a variety of methods to determine the structure of Sup35 amyloid fibrils. First, using fluorescent tags and cross-linking we identified specific segments of the protein monomer that form intermolecular contacts in a ``Head-to-Head,'' ``Tail-to-Tail'' fashion while a central region forms intramolecular contacts. Then, using peptide arrays we mapped the region responsible for the prion transmission barrier between two different yeast species. We have also used optical tweezers to reveal that the non-covalent intermolecular contacts between monomers are unusually strong, and maintain fibril integrity even under forces that partially unfold individual monomers and extend fibril length. Based on the handful of known yeast prion proteins we predicted sequences that could be responsible for prion-like amyloid folding. Our screen identified 19 new candidate prions, whose protein-folding properties and diverse cellular functions we have characterized using a combination of genetic and biochemical techniques. Prion-driven phenotypic diversity increases under stress, and can be amplified by the dynamic maturation of prion-initiating states. These qualities allow prions to act as ``bet-hedging'' devices that facilitate the adaptation of yeast to stressful environments, and might speed the evolution of new traits. Together with Kandel and Si, we have also found that a regulatory protein that plays an important role in synaptic plasticity behaves as a prion in yeast. Cytoplasmic polyAdenylation element binding protein, CPEB, maintains synapses by promoting

  5. Association of radiowave absorption with E(sporadic)-activity

    International Nuclear Information System (INIS)

    Ganguly, S.

    1975-01-01

    Noontime radiowave absorption data for frequencies which are reflected below the height of sporadic-E layers show a strong positive correlation with the sporadic-E layer activity. The possibilities of atmospheric waves affecting both the sporadic-E activity as well as mesospheric ionization are suggested to explain this association

  6. Genesis of mammalian prions: from non-infectious amyloid fibrils to a transmissible prion disease.

    Directory of Open Access Journals (Sweden)

    Natallia Makarava

    2011-12-01

    Full Text Available The transmissible agent of prion disease consists of a prion protein in its abnormal, β-sheet rich state (PrP(Sc, which is capable of replicating itself according to the template-assisted mechanism. This mechanism postulates that the folding pattern of a newly recruited polypeptide chain accurately reproduces that of a PrP(Sc template. Here we report that authentic PrP(Sc and transmissible prion disease can be generated de novo in wild type animals by recombinant PrP (rPrP amyloid fibrils, which are structurally different from PrP(Sc and lack any detectable PrP(Sc particles. When induced by rPrP fibrils, a long silent stage that involved two serial passages preceded development of the clinical disease. Once emerged, the prion disease was characterized by unique clinical, neuropathological, and biochemical features. The long silent stage to the disease was accompanied by significant transformation in neuropathological properties and biochemical features of the proteinase K-resistant PrP material (PrPres before authentic PrP(Sc evolved. The current work illustrates that transmissible prion diseases can be induced by PrP structures different from that of authentic PrP(Sc and suggests that a new mechanism different from the classical templating exists. This new mechanism designated as "deformed templating" postulates that a change in the PrP folding pattern from the one present in rPrP fibrils to an alternative specific for PrP(Sc can occur. The current work provides important new insight into the mechanisms underlying genesis of the transmissible protein states and has numerous implications for understanding the etiology of neurodegenerative diseases.

  7. SCREENING FOR GENETIC CHANGES AND CODON 129 POLYMORPHISM IN PRNP GENE IN HEALTHY SLOVENIAN POPULATION AND SPORADIC CASES OF CREUTZFELDT-JAKOB DISEASE

    Directory of Open Access Journals (Sweden)

    Sava Smerkolj

    2004-11-01

    Full Text Available Background. Prion protein has an important role in development of prion diseases, fatal neurodegenerative disorders. As the codon 129 genotype of the prion protein gene (PRNP is a known susceptibility factor for the diseases, we wanted to determine its distribution in healthy Slovenian population and also in cases of sporadic Creutzfeldt-Jakob disease (sCJD. Furthermore, we wanted to screen the whole gene in order to establish the presence of genetic changes.Methods. We screened 350 DNA samples of healthy blood donors and 12 DNA samples of patients deceased of sCJD. After the amplification and conformation analysis had been done, the gene was sequenced using an automatic sequencer.Results. Methionine homozygotes comprised 46.8% of healthy population, valine homozygotes 12.1% and heterozygotes 41.1%; out of 12 sCJD patients 10 were methionine homozygotes (83.3%, 1 was valine homozygote (8.3% and 1 was heterozygote (8.3%.Found SNPs were combination of codon 76 change (228C > T and codon 84 change (252T > C in a single sample of healthy population, combination of codon 68 change (204T > C and codon 76 change (228C > T in two samples of healthy population and codon 117 change (351A > G in a healthy population sample and in a valine homozygote patient.Conclusions. In comparison to the pooled Caucasian population is genotype M/M frequency slightly increased on account of decreased genotype M/V frequency in healthy Slovenian population, suggesting a little higher risk for acquiring a new variant of CJD (vCJD, because up to date all confirmed vCJD cases except one heterozygote were methionine homozygotes. Codon 129 genotype distribution in sCJD can be described as disease-specific. The absence of pathogenic mutations in sCJD patients confirms the non-familial, sporadic disease form.

  8. Sporadic colorectal polyps and mismatch repair proteins

    Directory of Open Access Journals (Sweden)

    Mahsa Molaei

    2011-01-01

    Full Text Available Background: Colorectal cancers often arise from benign polyps. Adenomatous polyps and serrated polyps progress step by step to adenocarcinoma and change into malignant cancers. Genetic and epigenetic changes have correlation with specific stages of polyp-adenocarcinoma progression and colorectal cancer histopathological changes. Aims: In this study we used immunohistochemistry (IHC staining in sporadic colorectal polyps to assay functional status of MLH1, MSH2, MSH6, and PMS2 proteins, to track genetic/epigenetic roles of this issue in our patients. Materials and Methods: In this cross-sectional study we assessed all patients who were admitted with sporadic colorectal polyps and underwent polypectomy in endoscopy department during 2004-2008. Result: IHC results were abnormal in 6.8% cases for MLH1, in 4.5% cases for MSH2, in 3% for MSH6, and in 4.8% for PMS2. In all cases with abnormal PMS2, MLH1 was also reported as abnormal. Same results were reported for abnormal MSH2, which is accompanied with abnormal MSH6 in all cases (P values < 0.001. There is no significant difference between IHC staining results, gender, dysplasia grade, adenomatous type, and invasion. On the other hand, there was significant difference between IHC staining results, polyp location, and mean age of patients. The same significant difference was between adenomatous polyps and serrated adenoma polyps by MLH1 and PMS2 (P values < 0.05. Conclusion: According to our findings, maybe MMR dysfunction is the cause of sporadic colorectal polyps in younger age and its increasing risk of dysplasia progression and malignancy progression is only in serrated adenoma. Sporadic polyps in left colon had a higher risk to progress to malignancies, and abnormal IHC staining for MLH1 and PMS2 in serrated polyps is much more than in other adenomatous polyps.

  9. Intraepithelial and interstitial deposition of pathological prion protein in kidneys of scrapie-affected sheep.

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    Ciriaco Ligios

    Full Text Available Prions have been documented in extra-neuronal and extra-lymphatic tissues of humans and various ruminants affected by Transmissible Spongiform Encephalopathy (TSE. The presence of prion infectivity detected in cervid and ovine blood tempted us to reason that kidney, the organ filtrating blood derived proteins, may accumulate disease associated PrP(Sc. We collected and screened kidneys of experimentally, naturally scrapie-affected and control sheep for renal deposition of PrP(Sc from distinct, geographically separated flocks. By performing Western blot, PET blot analysis and immunohistochemistry we found intraepithelial (cortex, medulla and papilla and occasional interstitial (papilla deposition of PrP(Sc in kidneys of scrapie-affected sheep. Interestingly, glomerula lacked detectable signals indicative of PrP(Sc. PrP(Sc was also detected in kidneys of subclinical sheep, but to significantly lower degree. Depending on the stage of the disease the incidence of PrP(Sc in kidney varied from approximately 27% (subclinical to 73.6% (clinical in naturally scrapie-affected sheep. Kidneys from flocks without scrapie outbreak were devoid of PrP(Sc. Here we demonstrate unexpectedly frequent deposition of high levels of PrP(Sc in ovine kidneys of various flocks. Renal deposition of PrP(Sc is likely to be a pre-requisite enabling prionuria, a possible co-factor of horizontal prion-transmission in sheep.

  10. Loss of Octarepeats in Two Processed Prion Pseudogenes in the Red Squirrel, Sciurus vulgaris

    Science.gov (United States)

    Kortum, Timothy T.; Hupkes, Marlinda; Kohlen, Wouter; van Rheede, Teun; de Jong, Wilfried W.

    2010-01-01

    The N-terminal region of the mammalian prion protein (PrP) contains an ‘octapeptide’ repeat which is involved in copper binding. This eight- or nine-residue peptide is repeated four to seven times, depending on the species, and polymorphisms in repeat number do occur. Alleles with three repeats are very rare in humans and goats, and deduced PrP sequences with two repeats have only been reported in two lemur species and in the red squirrel, Sciurus vulgaris. We here describe that the red squirrel two-repeat PrP sequence actually represents a retroposed pseudogene, and that an additional and older processed pseudogene with three repeats also occurs in this species as well as in ground squirrels. We argue that repeat numbers may tend to contract rather than expand in prion retropseudogenes, and that functional prion genes with two repeats may not be viable. Electronic supplementary material The online version of this article (doi:10.1007/s00239-010-9390-7) contains supplementary material, which is available to authorized users. PMID:20878152

  11. The ribosome-associated complex antagonizes prion formation in yeast.

    Science.gov (United States)

    Amor, Alvaro J; Castanzo, Dominic T; Delany, Sean P; Selechnik, Daniel M; van Ooy, Alex; Cameron, Dale M

    2015-01-01

    The number of known fungal proteins capable of switching between alternative stable conformations is steadily increasing, suggesting that a prion-like mechanism may be broadly utilized as a means to propagate altered cellular states. To gain insight into the mechanisms by which cells regulate prion formation and toxicity we examined the role of the yeast ribosome-associated complex (RAC) in modulating both the formation of the [PSI(+)] prion - an alternative conformer of Sup35 protein - and the toxicity of aggregation-prone polypeptides. The Hsp40 RAC chaperone Zuo1 anchors the RAC to ribosomes and stimulates the ATPase activity of the Hsp70 chaperone Ssb. We found that cells lacking Zuo1 are sensitive to over-expression of some aggregation-prone proteins, including the Sup35 prion domain, suggesting that co-translational protein misfolding increases in Δzuo1 strains. Consistent with this finding, Δzuo1 cells exhibit higher frequencies of spontaneous and induced prion formation. Cells expressing mutant forms of Zuo1 lacking either a C-terminal charged region required for ribosome association, or the J-domain responsible for Ssb ATPase stimulation, exhibit similarly high frequencies of prion formation. Our findings are consistent with a role for the RAC in chaperoning nascent Sup35 to regulate folding of the N-terminal prion domain as it emerges from the ribosome.

  12. Physical, chemical and kinetic factors affecting prion infectivity.

    Science.gov (United States)

    Properzi, Francesca; Badhan, Anjna; Klier, Steffi; Schmidt, Christian; Klöhn, Peter C; Wadsworth, Jonathan D F; Clarke, Anthony R; Jackson, Graham S; Collinge, John

    2016-05-03

    The mouse-adapted scrapie prion strain RML is one of the most widely used in prion research. The introduction of a cell culture-based assay of RML prions, the scrapie cell assay (SCA) allows more rapid and precise prion titration. A semi-automated version of this assay (ASCA) was applied to explore a range of conditions that might influence the infectivity and properties of RML prions. These include resistance to freeze-thaw procedures; stability to endogenous proteases in brain homogenate despite prolonged exposure to varying temperatures; distribution of infective material between pellet and supernatant after centrifugation, the effect of reducing agents and the influence of detergent additives on the efficiency of infection. Apparent infectivity is increased significantly by interaction with cationic detergents. Importantly, we have also elucidated the relationship between the duration of exposure of cells to RML prions and the transmission of infection. We established that the infection process following contact of cells with RML prions is rapid and followed an exponential time course, implying a single rate-limiting process.

  13. Mammalian prions: tolerance to sequence changes-how far?

    Science.gov (United States)

    Salamat, Muhammad Khalid; Munoz-Montesino, Carola; Moudjou, Mohammed; Rezaei, Human; Laude, Hubert; Béringue, Vincent; Dron, Michel

    2013-01-01

    Upon prion infection, abnormal prion protein (PrP (Sc) ) self-perpetuate by conformational conversion of α-helix-rich PrP (C) into β sheet enriched form, leading to formation and deposition of PrP (Sc) aggregates in affected brains. However the process remains poorly understood at the molecular level and the regions of PrP critical for conversion are still debated. Minimal amino acid substitutions can impair prion replication at many places in PrP. Conversely, we recently showed that bona fide prions could be generated after introduction of eight and up to 16 additional amino acids in the H2-H3 inter-helix loop of PrP. Prion replication also accommodated the insertions of an octapeptide at different places in the last turns of H2. This reverse genetic approach reveals an unexpected tolerance of prions to substantial sequence changes in the protease-resistant part which is associated with infectivity. It also demonstrates that conversion does not require the presence of a specific sequence in the middle of the H2-H3 area. We discuss the implications of our findings according to different structural models proposed for PrP (Sc) and questioned the postulated existence of an N- or C-terminal prion domain in the protease-resistant region.

  14. Cleaning, disinfection and sterilization of surface prion contamination.

    Science.gov (United States)

    McDonnell, G; Dehen, C; Perrin, A; Thomas, V; Igel-Egalon, A; Burke, P A; Deslys, J P; Comoy, E

    2013-12-01

    Prion contamination is a risk during device reprocessing, being difficult to remove and inactivate. Little is known of the combined effects of cleaning, disinfection and sterilization during a typical reprocessing cycle in clinical practice. To investigate the combination of cleaning, disinfection and/or sterilization on reducing the risk of surface prion contamination. In vivo test methods were used to study the impact of cleaning alone and cleaning combined with thermal disinfection and high- or low-temperature sterilization processes. A standardized test method, based on contamination of stainless steel wires with high titres of scrapie-infected brain homogenates, was used to determine infectivity reduction. Traditional chemical methods of surface decontamination against prions were confirmed to be effective, but extended steam sterilization was more variable. Steam sterilization alone reduced the risk of prion contamination under normal or extended exposure conditions, but did show significant variation. Thermal disinfection had no impact in these studies. Cleaning with certain defined formulations in combination with steam sterilization can be an effective prion decontamination process, in particular with alkaline formulations. Low-temperature, gaseous hydrogen peroxide sterilization was also confirmed to reduce infectivity in the presence and absence of cleaning. Prion decontamination is affected by the full reprocessing cycle used on contaminated surfaces. The correct use of defined cleaning, disinfection and sterilization methods as tested in this report in the scrapie infectivity assay can provide a standard precaution against prion contamination. Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  15. Aerosols transmit prions to immunocompetent and immunodeficient mice.

    Directory of Open Access Journals (Sweden)

    Johannes Haybaeck

    Full Text Available Prions, the agents causing transmissible spongiform encephalopathies, colonize the brain of hosts after oral, parenteral, intralingual, or even transdermal uptake. However, prions are not generally considered to be airborne. Here we report that inbred and crossbred wild-type mice, as well as tga20 transgenic mice overexpressing PrP(C, efficiently develop scrapie upon exposure to aerosolized prions. NSE-PrP transgenic mice, which express PrP(C selectively in neurons, were also susceptible to airborne prions. Aerogenic infection occurred also in mice lacking B- and T-lymphocytes, NK-cells, follicular dendritic cells or complement components. Brains of diseased mice contained PrP(Sc and transmitted scrapie when inoculated into further mice. We conclude that aerogenic exposure to prions is very efficacious and can lead to direct invasion of neural pathways without an obligatory replicative phase in lymphoid organs. This previously unappreciated risk for airborne prion transmission may warrant re-thinking on prion biosafety guidelines in research and diagnostic laboratories.

  16. Inheritable and sporadic non-autoimmune hyperthyroidism.

    Science.gov (United States)

    Ferraz, Carolina; Paschke, Ralf

    2017-03-01

    Hyperthyroidism is a clinical state that results from high thyroid hormone levels which has multiple etiologies, manifestations, and potential therapies. Excluding the autoimmune Graves disease, autonomic adenomas account for the most import cause of non-autoimmune hyperthyroidism. Activating germline mutations of the TSH receptor are rare etiologies for hyperthyroidism. They can be inherited in an autosomal dominant manner (familial or hereditary, FNAH), or may occur sporadically as a de novo condition, also called: persistent sporadic congenital non-autoimmune hyperthyroidism (PSNAH). These three conditions: autonomic adenoma, FNAH and PSNAH constitute the inheritable and sporadic non-autoimmune hyperthyroidism. Particularities in epidemiology, etiology, molecular and clinical aspects of these three entities will be discussed in this review in order to guide to an accurate diagnosis allowing among others genetic counseling and presymptomatic diagnosis for the affected families. The optimal treatment based on the right diagnosis will avoid consequences of a persistent or relapsing hyperthyroidism. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  17. Relationship between magnetism and prion protein

    Directory of Open Access Journals (Sweden)

    F. Balzano

    2010-01-01

    Full Text Available The mechanism of conversion of the normal prion protein (PrPC into aggregates of its pathological conformer (PrPSc reamins unclear. The aim of this study was to evaluate the effects induced by exposure of biological samples containing PrPSC to a magnetic field induced prominent molecular changes of samples indicated by the IR spectra located in the region that contains contribution primarily from absorption of amides. This finding suggests the existence of a strong correlation between magnetism and PrPsc and supports a new hypothesis that explains the conversion of normal PrPc to abnormal isoform PrPsc.

  18. [Human transmissible subacute spongiform encephalopathy].

    Science.gov (United States)

    Dormont, D

    1994-05-01

    Human transmissible spongiform encephalopathies (TSE) are rare chronic subacute degenerative diseases of the central nervous system (CNS) which include Creutzfeldt-Jakob disease (CJD), Kuru, Gerstmann-Sträussler-Scheinker syndrome (GSS), and Fatal Familial Insomnia (FFI). CJD can be either inherited or sporadic. All these diseases are always fatal. Neuropathological features are mainly constituted of neuronal vacuolisation, neuronal death, gliosis with hyperastrocytosis; plaques might be evidenced in kuru and GSS. Neither inflammatory syndrome nor demyelination is detectable. No virus like structure could be identified reproducibly. Human TSE are transmissible to non human primates and rodents. Iatrogenic CJD have been described after tissue grafting (cornea, dura mater), neurosurgery, electrophysiology investigation, and treatment with pituitary derived gonadotrophins and growth hormone. Molecular biochemistry of the CNS investigation revealed that a host encoded protein, the prion protein (PrP), accumulates proportionally to the infectious titer: this abnormality is the only detectable hallmark in TSE. Infectious fractions contain no detectable specific nucleic acid, and are mainly constituted of PrP under an isoform which resists to proteinase K digestion (PrP-res). The PrP gene (PRNP) is located on chromosome 20 in humans. Several mutations of this gene have been described in all inherited TSE (CJD, GSS, and IFF). No treatment is available today. Agents inducing TSE (TSA) are not known: several authors claim that TSA are only constituted of PrP-res; others support the hypothesis of a conventional agent with a specific genetic information.

  19. Protease-resistant prions selectively decrease Shadoo protein.

    Directory of Open Access Journals (Sweden)

    Joel C Watts

    2011-11-01

    Full Text Available The central event in prion diseases is the conformational conversion of the cellular prion protein (PrP(C into PrP(Sc, a partially protease-resistant and infectious conformer. However, the mechanism by which PrP(Sc causes neuronal dysfunction remains poorly understood. Levels of Shadoo (Sho, a protein that resembles the flexibly disordered N-terminal domain of PrP(C, were found to be reduced in the brains of mice infected with the RML strain of prions [1], implying that Sho levels may reflect the presence of PrP(Sc in the brain. To test this hypothesis, we examined levels of Sho during prion infection using a variety of experimental systems. Sho protein levels were decreased in the brains of mice, hamsters, voles, and sheep infected with different natural and experimental prion strains. Furthermore, Sho levels were decreased in the brains of prion-infected, transgenic mice overexpressing Sho and in infected neuroblastoma cells. Time-course experiments revealed that Sho levels were inversely proportional to levels of protease-resistant PrP(Sc. Membrane anchoring and the N-terminal domain of PrP both influenced the inverse relationship between Sho and PrP(Sc. Although increased Sho levels had no discernible effect on prion replication in mice, we conclude that Sho is the first non-PrP marker specific for prion disease. Additional studies using this paradigm may provide insight into the cellular pathways and systems subverted by PrP(Sc during prion disease.

  20. Comparison Between Sporadic and Misdiagnosed Sporadic Creutzfeldt-Jakob Disease: A Report of Two Cases.

    Science.gov (United States)

    Zhao, Xiongfei; Yu, Yingxin; Zhao, Zhiru; Xu, Jiaping

    2015-06-01

    Definite accurate diagnosis for Creutzfeldt-Jakob disease (CJD) depends on neuropathologic examination of brain biopsy or autopsy. However, transmissible nature makes the invasive examination dangerous. This study was set to determine that the clinical features are for the diagnosis of CJD through a comparison study. We compared clinical features of two cases with initial diagnosis of sporadic CJD. One case was finally diagnosed as definite sporadic CJD. According to World Health Organization diagnosis criteria, the other one, which had been diagnosed as probable sporadic CJD, was confirmed as limbic encephalitis after long-term follow-up. Compared with the case of definite sporadic CJD, the misdiagnosed case did not present typical electroencephalogram (EEG) and diffusion-weighted in magnetic resonance images (DWI) of CJD. However, cerebrospinal fluid in the misdiagnosed patient showed 14-3-3 protein positivity. The patient conditions improved after treatment. Through this case comparison, we conclude that EEG and DWI are necessary for accurate diagnosis of sporadic CJD. Further, long-term follow-up is crucial to diagnosis and treatment of CJD.

  1. Panencephalopathic Creutzfeldt-Jakob disease with distinct pattern of prion protein deposition in a patient with D178N mutation and homozygosity for valine at codon 129 of the prion protein Gene.

    Science.gov (United States)

    Marcon, Gabriella; Indaco, Antonio; Di Fede, Giuseppe; Suardi, Silvia; Finato, Nicoletta; Moretti, Valentino; Micoli, Sandro; Fociani, Paolo; Zerbi, Pietro; Pincherle, Alessandro; Redaelli, Veronica; Tagliavini, Fabrizio; Giaccone, Giorgio

    2014-03-01

    Prion diseases include sporadic, acquired and genetic forms linked to mutations of the prion protein (PrP) gene (PRNP). In subjects carrying the D178N PRNP mutation, distinct phenotypes can be observed, depending on the methionine/valine codon 129 polymorphism. We present here a 53-year-old woman with D178N mutation in the PRNP gene and homozygosity for valine at codon 129. The disease started at age 47 with memory deficits, progressive cognitive impairment and ataxia. The clinical picture slowly worsened to a state of akinetic mutism in about 2 years and the disease course was 6 years. The neuropathologic examination demonstrated severe diffuse cerebral atrophy with neuronal loss, spongiosis and marked myelin loss and tissue rarefaction in the hemispheric white matter, configuring panencephalopathic Creutzfeldt-Jakob disease. PrP deposition was present in the cerebral cortex, basal ganglia and cerebellum with diffuse synaptic-type pattern of immunoreactivity and clusters of countless, small PrP deposits, particularly evident in the lower cortical layers, in the striatum and in the molecular layer of the cerebellum. Western blot analysis showed the presence of type 1 PrP(Sc) (Parchi classification). These findings underline the clear-cut distinction between the neuropathological features of Creutzfeldt-Jakob disease associated with D178N PRNP mutation and those of fatal familial insomnia. © 2013 International Society of Neuropathology.

  2. Generating Bona Fide Mammalian Prions with Internal Deletions.

    Science.gov (United States)

    Munoz-Montesino, Carola; Sizun, Christina; Moudjou, Mohammed; Herzog, Laetitia; Reine, Fabienne; Chapuis, Jérôme; Ciric, Danica; Igel-Egalon, Angelique; Laude, Hubert; Béringue, Vincent; Rezaei, Human; Dron, Michel

    2016-08-01

    Mammalian prions are PrP proteins with altered structures causing transmissible fatal neurodegenerative diseases. They are self-perpetuating through formation of beta-sheet-rich assemblies that seed conformational change of cellular PrP. Pathological PrP usually forms an insoluble protease-resistant core exhibiting beta-sheet structures but no more alpha-helical content, loosing the three alpha-helices contained in the correctly folded PrP. The lack of a high-resolution prion structure makes it difficult to understand the dynamics of conversion and to identify elements of the protein involved in this process. To determine whether completeness of residues within the protease-resistant domain is required for prions, we performed serial deletions in the helix H2 C terminus of ovine PrP, since this region has previously shown some tolerance to sequence changes without preventing prion replication. Deletions of either four or five residues essentially preserved the overall PrP structure and mutant PrP expressed in RK13 cells were efficiently converted into bona fide prions upon challenge by three different prion strains. Remarkably, deletions in PrP facilitated the replication of two strains that otherwise do not replicate in this cellular context. Prions with internal deletion were self-propagating and de novo infectious for naive homologous and wild-type PrP-expressing cells. Moreover, they caused transmissible spongiform encephalopathies in mice, with similar biochemical signatures and neuropathologies other than the original strains. Prion convertibility and transfer of strain-specific information are thus preserved despite shortening of an alpha-helix in PrP and removal of residues within prions. These findings provide new insights into sequence/structure/infectivity relationship for prions. Prions are misfolded PrP proteins that convert the normal protein into a replicate of their own abnormal form. They are responsible for invariably fatal neurodegenerative

  3. Seizures in E200K familial and sporadic Creutzfeldt-Jakob disease.

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    Appel, S; Chapman, J; Cohen, O S; Rosenmann, H; Nitsan, Z; Blatt, I

    2015-03-01

    Although seizures (other than myoclonus) are frequently reported in Creutzfeldt-Jakob disease (CJD), their frequency, clinical manifestations, and effect on the disease course is unknown. To characterize the frequency of seizures in E200K familial and sporadic CJD, to describe its semiology, EEG and MRI findings. In this retrospective study, we reviewed all patients with CJD who were seen in the Sheba Medical Center between the years 2003-2012 and underwent clinical evaluation, genetic testing, EEG and MRI studies. The diagnosis of seizures was carried out based on documentation of episodes consistent with seizures or episode of unresponsiveness correlated with ictal activity in EEG. Sixty-four probable patients with CJD were included in the study, 57 (89%) with E200K familial (fCJD) and 7 (11%) with sporadic (sCJD). Seizures occurred in 8 patients: 3 of 7 (43%) in patients with sCJD compared to 5/57 (9%) in patients with E200K fCJD (P = 0.04, chi-square test). Two of E200K fCJD patients with seizures had other non-prion etiologies for seizures (brain metastasis, known history of temporal lobe epilepsy which started 44 years before the diagnosis of CJD). Seizures occurred late in the course of the disease with an average of 12 days between the onset of seizures and death. Seizures in E200K fCJD were infrequent and occurred late in the disease course. This difference suggests that E200K fCJD represents a separate subtype of the disease with distinct clinical characteristics. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. The genetics of radiation-induced and sporadic osteosarcoma: a unifying theory?

    International Nuclear Information System (INIS)

    Rosemann, Michael; Kuosaite, Virginija; Nathrath, Michaela; Atkinson, Michael J.

    2002-01-01

    Cancer is a disease of the genome, with the neoplastic phenotype being passed from one cell generation to the other. Radiation-induced cancer has often been considered to represent a unique entity amongst neoplasia, with the energy deposition being held responsible for both direct (gene mutations) and indirect (bystander effects, induced instability etc) alterations to the cellular genome. However, radiogenic tumours in man and experimental animals appear to be physiologically and genetically indistinguishable from their sporadic counterparts, suggesting that the aetiologies of these two tumour types are in fact closely related. We have conducted a general screen of the genetic alterations in radiation-induced mouse osteosarcoma, a tumour that is histopathologically indistinguishable from human sporadic osteosarcoma. Comparison of the two tumour types indicates the existence of a common set of genetic changes, providing additional evidence to support the concept that the molecular pathology of radiation-induced malignancy is no different to that of sporadic cancers. (author)

  5. Investigation on the relationship among sporadic Na, sporadic E, Field aligned irregularities and neutral winds

    Science.gov (United States)

    Sundararajan, Sridharan; Patra, Amit Kumar; Pant, Tarun; Gurubaran, Subramanian; Raghunath, Karnam

    In the Mesosphere and Lower Thermosphere region (80-100 km), metallic atoms, namely, sodium, potassium, lithium, Iron etc are formed due to ablation of meteors. The lidars based on resonance fluorescence principle has been used to study the vertical distribution of sodium atoms, because of their large abundance than other metals. The profiles of sodium density sometimes show enhancement by a factor of 2 than the normal layer in a narrow altitude region of 2 km and on these occasions, they are called sporadic sodium layer, or briefly Ns. On the other hand, there are observations on sporadic E and radar observations of Field Aligned Irregularities (FAI) associated with these sporadic E. Some investigations have been made to understand the relationship between sporadic E and FAI. Considering that sporadic E is composed of metallic ions and the time of metallic ions are larger compared to other ions, the sodium observations in the same height region would be of significant importance to understand the process involved. Despite a few past observations, no clear picture has emerged due to lack of simultaneous measurements of these parameters. The simultaneous observations of FAI echoes by the Indian MST radar and sodium concentration by the sodium lidar at Gadanki (13.5o N, 79.2o E) are being used to investigate the above mentioned relationship. The Sporadic E and neutral wind information are obtained from the ionosonde, meteor/MF radar observations from Trivandrum (8.5o N, 77E) and Tirunelveli (8.7o N, 77.8o E). The results obtained will be presented during the meeting.

  6. Expansion of the octarepeat domain alters the misfolding pathway but not the folding pathway of the prion protein.

    Science.gov (United States)

    Leliveld, S Rutger; Stitz, Lothar; Korth, Carsten

    2008-06-10

    A misfolded conformation of the prion protein (PrP), PrP (Sc), is the essential component of prions, the infectious agents that cause transmissible neurodegenerative diseases. Insertional mutations that lead to an increase in the number of octarepeats (ORs) in PrP are linked to familial human prion disease. In this study, we investigated how expansion of the OR domain causes PrP to favor a prion-like conformation. Therefore, we compared the conformational and aggregation modulating properties of wild-type versus expanded OR domains, either as a fusion construct with the protein G B1 domain (GB1-OR) or as an integral part of full-length mouse PrP (MoPrP). Using circular dichroism spectroscopy, we first demonstrated that ORs are not unfolded but exist as an ensemble of three distinct conformers: polyproline helix-like, beta-turn, and "Trp-related". Domain expansion had little effect on the conformation of GB1-OR fusion proteins. When part of MoPrP however, OR domain expansion changed PrP's folding landscape, not by hampering the production of native alpha-helical monomers but by greatly reducing the propensity to form amyloid and by altering the assembly of misfolded, beta-rich aggregates. These features may relate to subtle pH-dependent conformational differences between wild-type and mutant monomers. In conclusion, we propose that PrP insertional mutations are pathogenic because they enhance specific misfolding pathways of PrP rather than by undermining native folding. This idea was supported by a trial bioassay in transgenic mice overexpressing wild-type MoPrP, where intracerebral injection of recombinant MoPrP with an expanded OR domain but not wild-type MoPrP caused prion disease.

  7. Diagnostic approaches for viruses and prions in stem cell banks

    International Nuclear Information System (INIS)

    Cobo, Fernando; Talavera, Paloma; Concha, Angel

    2006-01-01

    Some stem cell lines may contain an endogenous virus or can be contaminated with exogenous viruses (even of animal origin) and may secrete viral particles or express viral antigens on their surface. Moreover, certain biotechnological products (e.g. bovine fetal serum, murine feeder cells) may contain prion particles. Viral and prion contamination of cell cultures and 'feeder' cells, which is a common risk in all biotechnological products derived from the cell lines, is the most challenging and potentially serious outcome to address, due to the difficulty involved in virus and prion detection and the potential to cause serious disease in recipients of these cell products. Stem cell banks should introduce adequate quality assurance programs like the microbiological control program and can provide researchers with valuable support in the standardization and safety of procedures and protocols used for the viral and prion testing and in validation programs to assure the quality and safety of the cells

  8. Putting prions into focus: application of single molecule detection to the diagnosis of prion diseases.

    Science.gov (United States)

    Giese, A; Bieschke, J; Eigen, M; Kretzschmar, H A

    2000-01-01

    Prion diseases are characterized by the cerebral deposition of an aggregated pathological isoform of the prion protein (PrP(Sc)) which constitutes the principal component of the transmissible agent termed prion. In order to develop a highly sensitive method for the detection of PrP(Sc) aggregates in biological samples such as cerebrospinal fluid (CSF), we used a method based on Fluorescence Correlation Spectroscopy (FCS), a technique which allows detection of single fluorescently labeled molecules in solution. Within the FCS setup, fluorescent photons emitted by molecules passing an open volume element defined by the beam of an excitation laser focussed into a diffraction-limited spot are imaged confocally onto a single photon counting detector. Aggregates of PrP(Sc) could be labeled by co-aggregation of probe molecules such as monomeric recombinant PrP or PrP-specific antibodies tagged with a fluorescent dye. In addition to slow diffusion, labeled aggregates are characterized by high fluorescence intensity, which allows detection and quantification by analysis of fluorescence intensity distribution. To improve detection of rare target particles, the accessible volume element was increased by scanning for intensely fluorescent targets (SIFT). To further improve sensitivity and specificity, two different probes were used simultaneously in a two-color setup. In a diagnostic model system of CSF spiked with purified prion rods, dual-color SIFT was more sensitive than Western blot analysis. In addition, a PrP(Sc)-specific signal was also detected in a number of CSF samples derived from CJD patients but not in controls.

  9. Sporadic Creutzfeldt–Jakob disease with cerebellar ataxia at onset in the UK

    Science.gov (United States)

    Cooper, S A; Murray, K L; Heath, C A; Will, R G; Knight, R S G

    2006-01-01

    Objective To determine the frequency, in the UK, of sporadic Creutzfeldt–Jakob Disease (sCJD) with a cerebellar ataxic onset, and to describe the clinical features of the syndrome. Methods A retrospective review of autopsy‐proved cases of sCJD cases in the UK, 1990–2005, identifying those presenting with cerebellar features without early cognitive decline. Results 29 of 618 (5%) patients with sCJD had an isolated cerebellar onset. Mean illness duration was 9 months. Subsequently, 21 (72%) developed myoclonus and 23 (79%) developed pyramidal features. Magnetic resonance imaging showed high signal in the basal ganglia in 11 of 14 (79%) patients. 7 of 15 (47%) patients were valine homozygotic at prion protein gene (PRNP)‐129. Only 8 (28%) cases were referred to the surveillance unit after death. Conclusion A better definition of sCJD presenting with an isolated cerebellar syndrome might improve future case recognition and contribute to the determination of its cause. PMID:16835290

  10. Case series of probable sporadic Creutzfeldt-Jakob disease from Eastern India

    Directory of Open Access Journals (Sweden)

    Atanu Biswas

    2013-01-01

    Full Text Available Background: Creutzfeldt-Jakob disease is a rapidly progressive, fatal, transmissible neurodegenerative disorder caused by prion protein. It is still considered rare in countries like India. This is probably due to nonavailability of autopsy studies in majority of the center. The recent European diagnostic criterion for sporadic CJD (sCJD is useful for making an early diagnosis. Objective: To report a series of patients of probable sCJD from a neurology institute of eastern India. Materials and Methods: Patients of rapidly developing dementia fulfilling the diagnostic criteria for sCJD were included. All were investigated in detail to find out any possible treatable cause including electroencephalography (EEG, magnetic resonance imaging (MRI of brain, and cerebrospinal fluid analysis. Results: A total 10 patients of probable sCJD diagnosed using the European diagnostic criterion between December 2011 and January 2013. The clinical features are consistent with other reported series. While 60% of patients had the classical EEG findings, 100% had typical MRI features. Eight patients died within a mean duration of 4.56 months from the disease onset. Conclusions: The clinical features are similar to other reported series. Our observation raises question about the prevalence of this disease in India which needs more elaborate studies.

  11. LGI1 antibody encephalopathy overlapping with sporadic Creutzfeldt-Jakob disease

    Science.gov (United States)

    Kim, Boaz; Yoo, Patrick; Sutherland, Tom; Boyd, Alison; Stehmann, Christiane; McLean, Catriona

    2016-01-01

    Objective: To report a rare case of leucine-rich, glioma inactivated 1 (LGI1) antibody–mediated autoimmune encephalopathy clinically overlapping with pathologically confirmed sporadic Creutzfeldt-Jakob disease (CJD). Methods: The patient was investigated with repeated brain MRI, EEG, CSF examination, whole-body fluorodeoxy-glucose positron emission tomography, genetic analysis of the prion protein gene (PRNP), and extensive serologic screening for paraneoplastic and autoimmune encephalopathy markers. Written informed consent was obtained from the patient's next of kin for access to clinical files for research purposes and for publication. Results: The patient was a 77-year-old man who presented with faciobrachial dystonic seizures (FBDS) secondary to LGI1 antibody–mediated autoimmune encephalopathy, with suggestive MRI findings and a complete response to treatment with combinatorial immunosuppression. Stereotactic biopsy of a nonenhancing T1 hyperintense basal ganglia lesion during the initial FBDS phase, albeit following immunosuppression, did not disclose evidence of lymphocytic inflammation. Following full remission of the FBDS, the patient manifested a rapidly progressive dementia associated with gross motor decline confirmed to be CJD at autopsy (molecular subtype VV3), with no evidence of a pathogenic PRNP mutation. Conclusions: Our patient highlights that these rare diseases are not invariably mutually exclusive and underscores the benefits of comprehensive neuropathologic examination of the brain to achieve an accurate diagnosis, especially in complex cases when the clinical trajectory dramatically deviates and a concomitant disease may need to be conscientiously considered to best explain the new clinical course. PMID:27354985

  12. Prions amplify through degradation of the VPS10P sorting receptor sortilin.

    Science.gov (United States)

    Uchiyama, Keiji; Tomita, Mitsuru; Yano, Masashi; Chida, Junji; Hara, Hideyuki; Das, Nandita Rani; Nykjaer, Anders; Sakaguchi, Suehiro

    2017-06-01

    Prion diseases are a group of fatal neurodegenerative disorders caused by prions, which consist mainly of the abnormally folded isoform of prion protein, PrPSc. A pivotal pathogenic event in prion disease is progressive accumulation of prions, or PrPSc, in brains through constitutive conformational conversion of the cellular prion protein, PrPC, into PrPSc. However, the cellular mechanism by which PrPSc is progressively accumulated in prion-infected neurons remains unknown. Here, we show that PrPSc is progressively accumulated in prion-infected cells through degradation of the VPS10P sorting receptor sortilin. We first show that sortilin interacts with PrPC and PrPSc and sorts them to lysosomes for degradation. Consistently, sortilin-knockdown increased PrPSc accumulation in prion-infected cells. In contrast, overexpression of sortilin reduced PrPSc accumulation in prion-infected cells. These results indicate that sortilin negatively regulates PrPSc accumulation in prion-infected cells. The negative role of sortilin in PrPSc accumulation was further confirmed in sortilin-knockout mice infected with prions. The infected mice had accelerated prion disease with early accumulation of PrPSc in their brains. Interestingly, sortilin was reduced in prion-infected cells and mouse brains. Treatment of prion-infected cells with lysosomal inhibitors, but not proteasomal inhibitors, increased the levels of sortilin. Moreover, sortilin was reduced following PrPSc becoming detectable in cells after infection with prions. These results indicate that PrPSc accumulation stimulates sortilin degradation in lysosomes. Taken together, these results show that PrPSc accumulation of itself could impair the sortilin-mediated sorting of PrPC and PrPSc to lysosomes for degradation by stimulating lysosomal degradation of sortilin, eventually leading to progressive accumulation of PrPSc in prion-infected cells.

  13. A Neuronal Culture System to Detect Prion Synaptotoxicity.

    Directory of Open Access Journals (Sweden)

    Cheng Fang

    2016-05-01

    Full Text Available Synaptic pathology is an early feature of prion as well as other neurodegenerative diseases. Although the self-templating process by which prions propagate is well established, the mechanisms by which prions cause synaptotoxicity are poorly understood, due largely to the absence of experimentally tractable cell culture models. Here, we report that exposure of cultured hippocampal neurons to PrPSc, the infectious isoform of the prion protein, results in rapid retraction of dendritic spines. This effect is entirely dependent on expression of the cellular prion protein, PrPC, by target neurons, and on the presence of a nine-amino acid, polybasic region at the N-terminus of the PrPC molecule. Both protease-resistant and protease-sensitive forms of PrPSc cause dendritic loss. This system provides new insights into the mechanisms responsible for prion neurotoxicity, and it provides a platform for characterizing different pathogenic forms of PrPSc and testing potential therapeutic agents.

  14. Yeast prions form infectious amyloid inclusion bodies in bacteria

    Directory of Open Access Journals (Sweden)

    Espargaró Alba

    2012-06-01

    Full Text Available Abstract Background Prions were first identified as infectious proteins associated with fatal brain diseases in mammals. However, fungal prions behave as epigenetic regulators that can alter a range of cellular processes. These proteins propagate as self-perpetuating amyloid aggregates being an example of structural inheritance. The best-characterized examples are the Sup35 and Ure2 yeast proteins, corresponding to [PSI+] and [URE3] phenotypes, respectively. Results Here we show that both the prion domain of Sup35 (Sup35-NM and the Ure2 protein (Ure2p form inclusion bodies (IBs displaying amyloid-like properties when expressed in bacteria. These intracellular aggregates template the conformational change and promote the aggregation of homologous, but not heterologous, soluble prionogenic molecules. Moreover, in the case of Sup35-NM, purified IBs are able to induce different [PSI+] phenotypes in yeast, indicating that at least a fraction of the protein embedded in these deposits adopts an infectious prion fold. Conclusions An important feature of prion inheritance is the existence of strains, which are phenotypic variants encoded by different conformations of the same polypeptide. We show here that the proportion of infected yeast cells displaying strong and weak [PSI+] phenotypes depends on the conditions under which the prionogenic aggregates are formed in E. coli, suggesting that bacterial systems might become useful tools to generate prion strain diversity.

  15. Enzymatic Digestion of Chronic Wasting Disease Prions Bound to Soil

    Science.gov (United States)

    SAUNDERS, SAMUEL E.; BARTZ, JASON C.; VERCAUTEREN, KURT C.; BARTELT-HUNT, SHANNON L.

    2010-01-01

    Chronic wasting disease (CWD) and sheep scrapie can be transmitted via indirect environmental routes, and it is known that soil can serve as a reservoir of prion infectivity. Given the strong interaction between the prion protein (PrP) and soil, we hypothesized that binding to soil enhances prion resistance to enzymatic digestion, thereby facilitating prion longevity in the environment and providing protection from host degradation. We characterized the performance of a commercially available subtilisin enzyme, the Prionzyme, to degrade soil-bound and unbound CWD and HY TME PrP as a function of pH, temperature, and treatment time. The subtilisin enzyme effectively degraded PrP adsorbed to a wide range of soils and soil minerals below the limits of detection. Signal loss occurred rapidly at high pH (12.5) and within 7 d under conditions representative of the natural environment (pH 7.4, 22°C). We observed no apparent difference in enzyme effectiveness between bound and unbound CWD PrP. Our results show that although adsorbed prions do retain relative resistance to enzymatic digestion compared with other brain homogenate proteins, they can be effectively degraded when bound to soil. Our results also suggest a topical application of a subtilisin enzyme solution may be an effective decontamination method to limit disease transmission via environmental ‘hot spots’ of prion infectivity. PMID:20450190

  16. Low copper and high manganese levels in prion protein plaques

    Science.gov (United States)

    Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

    2013-01-01

    Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

  17. Reduction of prion infectivity in packed red blood cells

    International Nuclear Information System (INIS)

    Morales, Rodrigo; Buytaert-Hoefen, Kimberley A.; Gonzalez-Romero, Dennisse; Castilla, Joaquin; Hansen, Eric T.; Hlavinka, Dennis; Goodrich, Raymond P.; Soto, Claudio

    2008-01-01

    The link between a new variant form of Creutzfeldt-Jakob disease (vCJD) and the consumption of prion contaminated cattle meat as well as recent findings showing that vCJD can be transmitted by blood transfusion have raised public health concerns. Currently, a reliable test to identify prions in blood samples is not available. The purpose of this study was to evaluate the possibility to remove scrapie prion protein (PrP Sc ) and infectivity from red blood cell (RBC) suspensions by a simple washing procedure using a cell separation and washing device. The extent of prion removal was assessed by Western blot, PMCA and infectivity bioassays. Our results revealed a substantial removal of infectious prions (≥3 logs of infectivity) by all techniques used. These data suggest that a significant amount of infectivity present in RBC preparations can be removed by a simple washing procedure. This technology may lead to increased safety of blood products and reduce the risk of further propagation of prion diseases.

  18. Strain-dependent profile of misfolded prion protein aggregates.

    Science.gov (United States)

    Morales, Rodrigo; Hu, Ping Ping; Duran-Aniotz, Claudia; Moda, Fabio; Diaz-Espinoza, Rodrigo; Chen, Baian; Bravo-Alegria, Javiera; Makarava, Natallia; Baskakov, Ilia V; Soto, Claudio

    2016-02-15

    Prions are composed of the misfolded prion protein (PrP(Sc)) organized in a variety of aggregates. An important question in the prion field has been to determine the identity of functional PrP(Sc) aggregates. In this study, we used equilibrium sedimentation in sucrose density gradients to separate PrP(Sc) aggregates from three hamster prion strains (Hyper, Drowsy, SSLOW) subjected to minimal manipulations. We show that PrP(Sc) aggregates distribute in a wide range of arrangements and the relative proportion of each species depends on the prion strain. We observed a direct correlation between the density of the predominant PrP(Sc) aggregates and the incubation periods for the strains studied. The relative presence of PrP(Sc) in fractions of different sucrose densities was indicative of the protein deposits present in the brain as analyzed by histology. Interestingly, no association was found between sensitivity to proteolytic degradation and aggregation profiles. Therefore, the organization of PrP molecules in terms of the density of aggregates generated may determine some of the particular strain properties, whereas others are independent from it. Our findings may contribute to understand the mechanisms of strain variation and the role of PrP(Sc) aggregates in prion-induced neurodegeneration.

  19. Synthetic prions with novel strain-specified properties.

    Science.gov (United States)

    Moda, Fabio; Le, Thanh-Nhat T; Aulić, Suzana; Bistaffa, Edoardo; Campagnani, Ilaria; Virgilio, Tommaso; Indaco, Antonio; Palamara, Luisa; Andréoletti, Olivier; Tagliavini, Fabrizio; Legname, Giuseppe

    2015-12-01

    Prions are infectious proteins that possess multiple self-propagating structures. The information for strains and structural specific barriers appears to be contained exclusively in the folding of the pathological isoform, PrP(Sc). Many recent studies determined that de novo prion strains could be generated in vitro from the structural conversion of recombinant (rec) prion protein (PrP) into amyloidal structures. Our aim was to elucidate the conformational diversity of pathological recPrP amyloids and their biological activities, as well as to gain novel insights in characterizing molecular events involved in mammalian prion conversion and propagation. To this end we generated infectious materials that possess different conformational structures. Our methodology for the prion conversion of recPrP required only purified rec full-length mouse (Mo) PrP and common chemicals. Neither infected brain extracts nor amplified PrP(Sc) were used. Following two different in vitro protocols recMoPrP converted to amyloid fibrils without any seeding factor. Mouse hypothalamic GT1 and neuroblastoma N2a cell lines were infected with these amyloid preparations as fast screening methodology to characterize the infectious materials. Remarkably, a large number of amyloid preparations were able to induce the conformational change of endogenous PrPC to harbor several distinctive proteinase-resistant PrP forms. One such preparation was characterized in vivo habouring a synthetic prion with novel strain specified neuropathological and biochemical properties.

  20. Disparate modes of evolution shaped modern prion (PRNP) and prion-related doppel (PRND) variation in domestic cattle

    Science.gov (United States)

    Previous investigations aimed at determining whether the mammalian prion protein actually facilitates tangible molecular aspects of either a discrete or pleiotropic functional niche have been debated, especially given the apparent absence of overt behavioral or physiological phenotypes associated wi...

  1. Early Detection of Sporadic Pancreatic Cancer

    Science.gov (United States)

    Kenner, Barbara J.; Chari, Suresh T.; Cleeter, Deborah F.; Go, Vay Liang W.

    2015-01-01

    Abstract Innovation leading to significant advances in research and subsequent translation to clinical practice is urgently necessary in early detection of sporadic pancreatic cancer. Addressing this need, the Early Detection of Sporadic Pancreatic Cancer Summit Conference was conducted by Kenner Family Research Fund in conjunction with the 2014 American Pancreatic Association and Japan Pancreas Society Meeting. International interdisciplinary scientific representatives engaged in strategic facilitated conversations based on distinct areas of inquiry: Case for Early Detection: Definitions, Detection, Survival, and Challenges; Biomarkers for Early Detection; Imaging; and Collaborative Studies. Ideas generated from the summit have led to the development of a Strategic Map for Innovation built upon 3 components: formation of an international collaborative effort, design of an actionable strategic plan, and implementation of operational standards, research priorities, and first-phase initiatives. Through invested and committed efforts of leading researchers and institutions, philanthropic partners, government agencies, and supportive business entities, this endeavor will change the future of the field and consequently the survival rate of those diagnosed with pancreatic cancer. PMID:25938853

  2. Early Detection of Sporadic Pancreatic Cancer

    Science.gov (United States)

    Chari, Suresh T.; Kelly, Kimberly; Hollingsworth, Michael A.; Thayer, Sarah P.; Ahlquist, David A.; Andersen, Dana K.; Batra, Surinder K.; Brentnall, Teresa A.; Canto, Marcia; Cleeter, Deborah F.; Firpo, Matthew A.; Gambhir, Sanjiv Sam; Go, Vay Liang W.; Hines, O. Joe; Kenner, Barbara J.; Klimstra, David S.; Lerch, Markus M.; Levy, Michael J.; Maitra, Anirban; Mulvihill, Sean J.; Petersen, Gloria M.; Rhim, Andrew D.; Simeone, Diane M.; Srivastava, Sudhir; Tanaka, Masao; Vinik, Aaron I.; Wong, David

    2015-01-01

    Abstract Pancreatic cancer (PC) is estimated to become the second leading cause of cancer death in the United States by 2020. Early detection is the key to improving survival in PC. Addressing this urgent need, the Kenner Family Research Fund conducted the inaugural Early Detection of Sporadic Pancreatic Cancer Summit Conference in 2014 in conjunction with the 45th Anniversary Meeting of the American Pancreatic Association and Japan Pancreas Society. This seminal convening of international representatives from science, practice, and clinical research was designed to facilitate challenging interdisciplinary conversations to generate innovative ideas leading to the creation of a defined collaborative strategic pathway for the future of the field. An in-depth summary of current efforts in the field, analysis of gaps in specific areas of expertise, and challenges that exist in early detection is presented within distinct areas of inquiry: Case for Early Detection: Definitions, Detection, Survival, and Challenges; Biomarkers for Early Detection; Imaging; and Collaborative Studies. In addition, an overview of efforts in familial PC is presented in an addendum to this article. It is clear from the summit deliberations that only strategically designed collaboration among investigators, institutions, and funders will lead to significant progress in early detection of sporadic PC. PMID:25931254

  3. Disease Transmission by Misfolded Prion-Protein Isoforms, Prion-Like Amyloids, Functional Amyloids and the Central Dogma.

    Science.gov (United States)

    Daus, Martin L

    2016-01-04

    In 1982, the term "prions" (proteinaceous infectious particles) was coined to specify a new principle of infection. A misfolded isoform of a cellular protein has been described as the causative agent of a fatal neurodegenerative disease. At the beginning of prion research scientists assumed that the infectious agent causing transmissible spongiform encephalopathy (TSE) was a virus, but some unconventional properties of these pathogens were difficult to bring in line with the prevailing viral model. The discovery that prions (obviously devoid of any coding nucleic acid) can store and transmit information similarly to DNA was initially even denoted as being "heretical" but is nowadays mainly accepted by the scientific community. This review describes, from a historical point of view, how the "protein-only hypothesis" expands the Central Dogma. Definition of both, the prion principle and the Central Dogma, have been essential steps to understand information storage and transfer within and among cells and organisms. Furthermore, the current understanding of the infectivity of prion-proteins after misfolding is summarized succinctly. Finally, prion-like amyloids and functional amyloids, as found in yeast and bacteria, will be discussed.

  4. Increased expression of p62/SQSTM1 in prion diseases and its association with pathogenic prion protein.

    Science.gov (United States)

    Homma, Takujiro; Ishibashi, Daisuke; Nakagaki, Takehiro; Satoh, Katsuya; Sano, Kazunori; Atarashi, Ryuichiro; Nishida, Noriyuki

    2014-03-28

    Prion diseases are neurodegenerative disorders characterized by the aggregation of abnormally folded prion protein (PrP(Sc)). In this study, we focused on the mechanism of clearance of PrP(Sc), which remains unclear. p62 is a cytosolic protein known to mediate both the formation and degradation of aggregates of abnormal proteins. The levels of p62 protein increased in prion-infected brains and persistently infected cell cultures. Upon proteasome inhibition, p62 co-localized with PrP(Sc), forming a large aggregate in the perinuclear region, hereafter referred to as PrP(Sc)-aggresome. These aggregates were surrounded with autophagosome marker LC3 and lysosomes in prion-infected cells. Moreover, transient expression of the phosphomimic form of p62, which has enhanced ubiquitin-binding activity, reduced the amount of PrP(Sc) in prion-infected cells, indicating that the activation of p62 could accelerate the clearance of PrP(Sc). Our findings would thus suggest that p62 could be a target for the therapeutic control of prion diseases.

  5. An emerging role for misfolded wild-type SOD1 in sporadic ALS pathogenesis

    Directory of Open Access Journals (Sweden)

    Melissa S Rotunno

    2013-12-01

    Full Text Available Amyotrophic lateral sclerosis (ALS is a fatal neurodegenerative disorder that targets motor neurons, leading to paralysis and death within a few years of disease onset. While several genes have been linked to the inheritable, or familial, form of ALS, much less is known about the cause(s of sporadic ALS, which accounts for approximately 90% of ALS cases. Due to the clinical similarities between familial and sporadic ALS, it is plausible that both forms of the disease converge on a common pathway and, therefore, involve common factors. Recent evidence suggests the Cu,Zn-superoxide dismutase (SOD1 protein to be one such factor that is common to both sporadic and familial ALS. In 1993, mutations were uncovered in SOD1 that represent the first known genetic cause of familial ALS. While the exact mechanism of mutant-SOD1 toxicity is still not known today, most evidence points to a gain of toxic function that stems, at least in part, from the propensity of this protein to misfold. In the wild-type SOD1 protein, non-genetic perturbations such as metal depletion, disruption of the quaternary structure, and oxidation, can also induce SOD1 to misfold. In fact, these aforementioned post-translational modifications cause wild-type SOD1 to adopt a toxic conformation that is similar to familial ALS-linked SOD1 variants. These observations, together with the detection of misfolded wild-type SOD1 within human post-mortem sporadic ALS samples, have been used to support the controversial hypothesis that misfolded forms of wild-type SOD1 contribute to sporadic ALS pathogenesis. In this review, we present data from the literature that both support and contradict this hypothesis. We also discuss SOD1 as a potential therapeutic target for both familial and sporadic ALS.

  6. Encefalopatía por priones

    Directory of Open Access Journals (Sweden)

    Carlos Colegial

    1999-01-01

    Full Text Available Las encefalopatías espongiformes por priones son enfermedades neurodegenerativas que pueden ser esporádicas o transmisibles, ya sea por mecanismos infecciosos o hereditarios. Su investigación ha planteado enormes retos y en el recorrido histórico en busca de su causa dos médicos han recibido el premio Nobel de Medicina: Carleton Gajdusek, por sus trabajos en Nueva Guinea donde describió la transmisión infecciosa por ritos canibalísticos, que llevó a estudios de transmisión experimental en chimpancés y a su teoría de los "virus lentos" (por el largo período de incubación de la enfermedad.

  7. Elucidation of Prion Protein Conformational Changes Associated with Infectivity by Fluorescence Spectroscopy

    Science.gov (United States)

    2007-06-01

    is not known. Obtaining structural information on the misfolded isoform of prion may lead to preventative therapies and treatments of prion diseases...the misfolded prion isoform may allow for the development of drug therapies or early detection systems for prion diseases, or illuminate mechanistic...showing fluorescence intensity as a function of time and energy for 2,6-p-toluidinonapththalene adsorbed to egg L-α- lecithin vesicles. The steady

  8. Ubiquitin Ligase gp78 Targets Unglycosylated Prion Protein PrP for Ubiquitylation and Degradation

    OpenAIRE

    Shao, Jia; Choe, Vitnary; Cheng, Haili; Tsai, Yien Che; Weissman, Allan M.; Luo, Shiwen; Rao, Hai

    2014-01-01

    Prion protein PrP is a central player in several devastating neurodegenerative disorders, including mad cow disease and Creutzfeltd-Jacob disease. Conformational alteration of PrP into an aggregation-prone infectious form PrPSc can trigger pathogenic events. How levels of PrP are regulated is poorly understood. Human PrP is known to be degraded by the proteasome, but the specific proteolytic pathway responsible for PrP destruction remains elusive. Here, we demonstrate that the ubiquitin ligas...

  9. Sporadic wind wave horse-shoe patterns

    Directory of Open Access Journals (Sweden)

    S. Yu. Annenkov

    1999-01-01

    Full Text Available The work considers three-dimensional crescent-shaped patterns often seen on water surface in natural basins and observed in wave tank experiments. The most common of these 'horse-shoe-like' patterns appear to be sporadic, i.e., emerging and disappearing spontaneously even under steady wind conditions. The paper suggests a qualitative model of these structures aimed at explaining their sporadic nature, physical mechanisms of their selection and their specific asymmetric form. First, the phenomenon of sporadic horse-shoe patterns is studied numerically using the novel algorithm of water waves simulation recently developed by the authors (Annenkov and Shrira, 1999. The simulations show that a steep gravity wave embedded into widespectrum primordial noise and subjected to small nonconservative effects typically follows the simple evolution scenario: most of the time the system can be considered as consisting of a basic wave and a single pair of oblique satellites, although the choice of this pair tends to be different at different instants. Despite the effective low-dimensionality of the multimodal system dynamics at relatively sho ' rt time spans, the role of small satellites is important: in particular, they enlarge the maxima of the developed satellites. The presence of Benjamin-Feir satellites appears to be of no qualitative importance at the timescales under consideration. The selection mechanism has been linked to the quartic resonant interactions among the oblique satellites lying in the domain of five-wave (McLean's class II instability of the basic wave: the satellites tend to push each other out of the resonance zone due to the frequency shifts caused by the quartic interactions. Since the instability domain is narrow (of order of cube of the basic wave steepness, eventually in a generic situation only a single pair survives and attains considerable amplitude. The specific front asymmetry is found to result from the interplay of quartic

  10. Mapping of possible prion protein self interaction domains using peptide arrays

    NARCIS (Netherlands)

    Rigter, A.; Langeveld, J.P.M.; Timmers-Parohi, D.; Jacobs, J.G.; Moonen, P.L.J.M.; Bossers, A.

    2007-01-01

    Background The common event in transmissible spongiform encephalopathies (TSEs) or prion diseases is the conversion of host-encoded protease sensitive cellular prion protein (PrPC) into strain dependent isoforms of scrapie associated protease resistant isoform (PrPSc) of prion protein (PrP). These

  11. Prion protein amyloidosis with divergent phenotype associated with two novel nonsense mutations in PRNP

    NARCIS (Netherlands)

    Jansen, Casper; Parchi, Piero; Capellari, Sabina; Vermeij, Ad J.; Corrado, Patrizia; Baas, Frank; Strammiello, Rosaria; van Gool, Willem A.; van Swieten, John C.; Rozemuller, Annemieke J. M.

    2010-01-01

    Stop codon mutations in the gene encoding the prion protein (PRNP) are very rare and have thus far only been described in two patients with prion protein cerebral amyloid angiopathy (PrP-CAA). In this report, we describe the clinical, histopathological and pathological prion protein (PrPSc)

  12. Using small molecule reagents to help distinguish among prion structural models

    Science.gov (United States)

    The only demonstrated difference between infectious prions (PrPSc) and the isosequential normal cellular prion protein (PrPC) is conformation. The structure of PrPC has been determined by a variety of instrumental techniques. The structure of prions remains uncertain. Recent instrumental analysis h...

  13. Correlation of cellular factors and differential scrapie prion permissiveness in ovine microglia

    Science.gov (United States)

    Prion diseases are fatal neurodegenerative disorders by which the native cellular prion protein (PrP-C) is misfolded into an accumulating, disease-associated isoform (PrP-D). To improve the understanding of prion pathogenesis and develop effective treatments, it is essential to elucidate factors con...

  14. Combined copper/zinc attachment to prion protein

    Science.gov (United States)

    Hodak, Miroslav; Bernholc, Jerry

    2013-03-01

    Misfolding of prion protein (PrP) is responsible for diseases such as ``mad-cow disease'' in cattle and Creutzfeldt-Jacob in humans. Extensive experimental investigation has established that this protein strongly interacts with copper ions, and this ability has been linked to its still unknown function. Attachment of other metal ions (zinc, iron, manganese) have been demonstrated as well, but none of them could outcompete copper. Recent finding, however, indicates that at intermediate concentrations both copper and zinc ions can attach to the PrP at the octarepeat region, which contains high affinity metal binding sites. Based on this evidence, we have performed density functional theory simulations to investigate the combined Cu/Zn attachment. We consider all previously reported binding modes of copper at the octarepeat region and examine a possibility simultaneous Cu/Zn attachment. We find that this can indeed occur for only one of the known binding sites, when copper changes its coordination mode to allow for attachment of zinc ion. The implications of the simultaneous attachment on neural function remain to be explored.

  15. Instability of familial spongiform encephalopathy-related prion mutants

    International Nuclear Information System (INIS)

    Watanabe, Yasuko; Hiraoka, Wakako; Shimoyama, Yuhei; Horiuchi, Motohiro; Kuwabara, Mikinori; Inanami, Osamu

    2008-01-01

    We examined the influence of D177N (D178N in humans) mutation on the conformational stability of the S2 region of moPrP C with varying pHs by using the SDSL-ESR technique. The ESR spectrum of D177N at pH 7.5 was narrower than that of Y161R1, referred to as WT * . The ESR spectrum of D177N did not change when pH in the solution decreased to pH 4.0. Our results suggested that the disappearance of a salt bridge (D177-R163) induced the increase in the instability of S2 region. Moreover, the line shape of the ESR spectrum obtained from H176S neighboring the salt bridge linked to the S2 region was similar to D177N. These results indicate that the protonation of H176 is strongly associated with the stability of S2 region. These findings are important for understanding the mechanism by which the disruption of the salt bridge in the S2 region forms the pathogenic PrP Sc structure in hereditary prion disease

  16. Prion protein modulates glucose homeostasis by altering intracellular iron.

    Science.gov (United States)

    Ashok, Ajay; Singh, Neena

    2018-04-26

    The prion protein (PrP C ), a mainly neuronal protein, is known to modulate glucose homeostasis in mouse models. We explored the underlying mechanism in mouse models and the human pancreatic β-cell line 1.1B4. We report expression of PrP C on mouse pancreatic β-cells, where it promoted uptake of iron through divalent-metal-transporters. Accordingly, pancreatic iron stores in PrP knockout mice (PrP -/- ) were significantly lower than wild type (PrP +/+ ) controls. Silencing of PrP C in 1.1B4 cells resulted in significant depletion of intracellular (IC) iron, and remarkably, upregulation of glucose transporter GLUT2 and insulin. Iron overloading, on the other hand, resulted in downregulation of GLUT2 and insulin in a PrP C -dependent manner. Similar observations were noted in the brain, liver, and neuroretina of iron overloaded PrP +/+ but not PrP -/- mice, indicating PrP C -mediated modulation of insulin and glucose homeostasis through iron. Peripheral challenge with glucose and insulin revealed blunting of the response in iron-overloaded PrP +/+ relative to PrP -/- mice, suggesting that PrP C -mediated modulation of IC iron influences both secretion and sensitivity of peripheral organs to insulin. These observations have implications for Alzheimer's disease and diabetic retinopathy, known complications of type-2-diabetes associated with brain and ocular iron-dyshomeostasis.

  17. Selective propagation of mouse-passaged scrapie prions with long incubation period from a mixed prion population using GT1-7 cells.

    Directory of Open Access Journals (Sweden)

    Kohtaro Miyazawa

    Full Text Available In our previous study, we demonstrated the propagation of mouse-passaged scrapie isolates with long incubation periods (L-type derived from natural Japanese sheep scrapie cases in murine hypothalamic GT1-7 cells, along with disease-associated prion protein (PrPSc accumulation. We here analyzed the susceptibility of GT1-7 cells to scrapie prions by exposure to infected mouse brains at different passages, following interspecies transmission. Wild-type mice challenged with a natural sheep scrapie case (Kanagawa exhibited heterogeneity of transmitted scrapie prions in early passages, and this mixed population converged upon one with a short incubation period (S-type following subsequent passages. However, when GT1-7 cells were challenged with these heterologous samples, L-type prions became dominant. This study demonstrated that the susceptibility of GT1-7 cells to L-type prions was at least 105 times higher than that to S-type prions and that L-type prion-specific biological characteristics remained unchanged after serial passages in GT1-7 cells. This suggests that a GT1-7 cell culture model would be more useful for the economical and stable amplification of L-type prions at the laboratory level. Furthermore, this cell culture model might be used to selectively propagate L-type scrapie prions from a mixed prion population.

  18. 75 FR 38958 - Declaration of Prion as a Pest under FIFRA and Amendment of EPA's Regulatory Definition of Pests...

    Science.gov (United States)

    2010-07-07

    ... Prion as a Pest under FIFRA and Amendment of EPA's Regulatory Definition of Pests to Include Prion....e., proteinaceous infectious particle) a ``pest'' under the Federal Insecticide, Fungicide, and... is adding prion to the list of pests in EPA's regulations. This amendment, together with the formal...

  19. Resistance to chronic wasting disease in transgenic mice expressing a naturally occurring allelic variant of deer prion protein

    NARCIS (Netherlands)

    Meade-White, K.; Race, B.; Trifilo, M.; Bossers, A.; Favara, C.; Lacasse, R.; Miller, M.; Williams, E.; Oldstone, M.; Race, R.; Chesebro, B.

    2007-01-01

    Prion protein (PrP) is a required factor for susceptibility to transmissible spongiform encephalopathy or prion diseases. In transgenic mice, expression of prion protein (PrP) from another species often confers susceptibility to prion disease from that donor species. For example, expression of deer

  20. MRI of sporadic Creutzfeldt-Jakob disease

    International Nuclear Information System (INIS)

    Kong, A.; Vliet, A. Van der.

    2008-01-01

    Full text: The key MRI findings in five cases of sporadic Creutzfeldt-Jakob disease (CJD) are illustrated with four 'definite' and one 'probable' according to World Health Organization criteria. Close attention to fluid-attenuation inversion recovery and diffusion-weighted imaging sequences are important for diagnosis, noting especially restricted diffusion in cortical and deep grey matter. Our study and those of others show predominant cortical, caudate and thalamic involvement. This pattern is highly sensitive and specific for the diagnosis. Fluid-attenuation inversion recovery and diffusion-weighted imaging signal abnormality becomes progressively more extensive and bilateral as disease progresses, but may become less pronounced in end-stage disease because of atrophy.

  1. The prion-ZIP connection: From cousins to partners in iron uptake

    Science.gov (United States)

    Singh, Neena; Asthana, Abhishek; Baksi, Shounak; Desai, Vilok; Haldar, Swati; Hari, Sahi; Tripathi, Ajai K

    2015-01-01

    ABSTRACT Converging observations from disparate lines of inquiry are beginning to clarify the cause of brain iron dyshomeostasis in sporadic Creutzfeldt-Jakob disease (sCJD), a neurodegenerative condition associated with the conversion of prion protein (PrPC), a plasma membrane glycoprotein, from α-helical to a β-sheet rich PrP-scrapie (PrPSc) isoform. Biochemical evidence indicates that PrPC facilitates cellular iron uptake by functioning as a membrane-bound ferrireductase (FR), an activity necessary for the transport of iron across biological membranes through metal transporters. An entirely different experimental approach reveals an evolutionary link between PrPC and the Zrt, Irt-like protein (ZIP) family, a group of proteins involved in the transport of zinc, iron, and manganese across the plasma membrane. Close physical proximity of PrPC with certain members of the ZIP family on the plasma membrane and increased uptake of extracellular iron by cells that co-express PrPC and ZIP14 suggest that PrPC functions as a FR partner for certain members of this family. The connection between PrPC and ZIP proteins therefore extends beyond common ancestry to that of functional cooperation. Here, we summarize evidence supporting the facilitative role of PrPC in cellular iron uptake, and implications of this activity on iron metabolism in sCJD brains. PMID:26689487

  2. Functional interactions of nucleocapsid protein of feline immunodeficiency virus and cellular prion protein with the viral RNA.

    Science.gov (United States)

    Moscardini, Mila; Pistello, Mauro; Bendinelli, M; Ficheux, Damien; Miller, Jennifer T; Gabus, Caroline; Le Grice, Stuart F J; Surewicz, Witold K; Darlix, Jean-Luc

    2002-04-19

    All lentiviruses and oncoretroviruses examined so far encode a major nucleic-acid binding protein (nucleocapsid or NC* protein), approximately 2500 molecules of which coat the dimeric RNA genome. Studies on HIV-1 and MoMuLV using in vitro model systems and in vivo have shown that NC protein is required to chaperone viral RNA dimerization and packaging during virus assembly, and proviral DNA synthesis by reverse transcriptase (RT) during infection. The human cellular prion protein (PrP), thought to be the major component of the agent causing transmissible spongiform encephalopathies (TSE), was recently found to possess a strong affinity for nucleic acids and to exhibit chaperone properties very similar to HIV-1 NC protein in the HIV-1 context in vitro. Tight binding of PrP to nucleic acids is proposed to participate directly in the prion disease process. To extend our understanding of lentiviruses and of the unexpected nucleic acid chaperone properties of the human prion protein, we set up an in vitro system to investigate replication of the feline immunodeficiency virus (FIV), which is functionally and phylogenetically distant from HIV-1. The results show that in the FIV model system, NC protein chaperones viral RNA dimerization, primer tRNA(Lys,3) annealing to the genomic primer-binding site (PBS) and minus strand DNA synthesis by the homologous FIV RT. FIV NC protein is able to trigger specific viral DNA synthesis by inhibiting self-priming of reverse transcription. The human prion protein was found to mimic the properties of FIV NC with respect to primer tRNA annealing to the viral RNA and chaperoning minus strand DNA synthesis. Copyright 2002 Elsevier Science Ltd.

  3. The lunar tide in sporadic E

    Directory of Open Access Journals (Sweden)

    R. J. Stening

    1999-10-01

    Full Text Available It seems that the wind shear theory is accepted for the explanation of sporadic E at mid and low latitudes. Some examples from Arecibo are displayed to show this. The effect of lunar tides should then modify the wind-shear theory in a manner that yields the observed features of the lunar tide in the critical frequency foEs and the height h'Es of the sporadic E. This is shown to imply that the phase of the lunar tide in h'Es should be the same as the phase of the lunar tide in the eastward wind and that the phase of the lunar tide in foEs is three hours later. Hourly values of foEs, f bEs (the blanketing critical frequency and h'Es from several observatories are analysed for the lunar semidiurnal tide. It is found that the phase of the tide in foEs is often about 3 hours later than for h'Es in agreement with the theory. Seasonal variations in the tide are also examined with the statistically most significant results (largest amplitudes usually occurring in summer. After reviewing the many difficulties associated with determining the lunar tide in Es, both experimentally and theoretically, the analysed phase results are compared with what might be expected from Hagan's global scale wave model. Agreement is only fair (a success rate of 69% among the cases examined but probably as good as might be expected.Key words. Ionosphere (ionosphere – atmosphere interactions – ionospheric irregularities, Meteorology and atmosphere dynamics (waves and tides

  4. Genetic Predictions of Prion Disease Susceptibility in Carnivore Species Based on Variability of the Prion Gene Coding Region

    Science.gov (United States)

    Stewart, Paula; Campbell, Lauren; Skogtvedt, Susan; Griffin, Karen A.; Arnemo, Jon M.; Tryland, Morten; Girling, Simon; Miller, Michael W.; Tranulis, Michael A.; Goldmann, Wilfred

    2012-01-01

    Mammalian species vary widely in their apparent susceptibility to prion diseases. For example, several felid species developed prion disease (feline spongiform encephalopathy or FSE) during the bovine spongiform encephalopathy (BSE) epidemic in the United Kingdom, whereas no canine BSE cases were detected. Whether either of these or other groups of carnivore species can contract other prion diseases (e.g. chronic wasting disease or CWD) remains an open question. Variation in the host-encoded prion protein (PrPC) largely explains observed disease susceptibility patterns within ruminant species, and may explain interspecies differences in susceptibility as well. We sequenced and compared the open reading frame of the PRNP gene encoding PrPC protein from 609 animal samples comprising 29 species from 22 genera of the Order Carnivora; amongst these samples were 15 FSE cases. Our analysis revealed that FSE cases did not encode an identifiable disease-associated PrP polymorphism. However, all canid PrPs contained aspartic acid or glutamic acid at codon 163 which we propose provides a genetic basis for observed susceptibility differences between canids and felids. Among other carnivores studied, wolverine (Gulo gulo) and pine marten (Martes martes) were the only non-canid species to also express PrP-Asp163, which may impact on their prion diseases susceptibility. Populations of black bear (Ursus americanus) and mountain lion (Puma concolor) from Colorado showed little genetic variation in the PrP protein and no variants likely to be highly resistant to prions in general, suggesting that strain differences between BSE and CWD prions also may contribute to the limited apparent host range of the latter. PMID:23236380

  5. Genetic predictions of prion disease susceptibility in carnivore species based on variability of the prion gene coding region.

    Directory of Open Access Journals (Sweden)

    Paula Stewart

    Full Text Available Mammalian species vary widely in their apparent susceptibility to prion diseases. For example, several felid species developed prion disease (feline spongiform encephalopathy or FSE during the bovine spongiform encephalopathy (BSE epidemic in the United Kingdom, whereas no canine BSE cases were detected. Whether either of these or other groups of carnivore species can contract other prion diseases (e.g. chronic wasting disease or CWD remains an open question. Variation in the host-encoded prion protein (PrP(C largely explains observed disease susceptibility patterns within ruminant species, and may explain interspecies differences in susceptibility as well. We sequenced and compared the open reading frame of the PRNP gene encoding PrP(C protein from 609 animal samples comprising 29 species from 22 genera of the Order Carnivora; amongst these samples were 15 FSE cases. Our analysis revealed that FSE cases did not encode an identifiable disease-associated PrP polymorphism. However, all canid PrPs contained aspartic acid or glutamic acid at codon 163 which we propose provides a genetic basis for observed susceptibility differences between canids and felids. Among other carnivores studied, wolverine (Gulo gulo and pine marten (Martes martes were the only non-canid species to also express PrP-Asp163, which may impact on their prion diseases susceptibility. Populations of black bear (Ursus americanus and mountain lion (Puma concolor from Colorado showed little genetic variation in the PrP protein and no variants likely to be highly resistant to prions in general, suggesting that strain differences between BSE and CWD prions also may contribute to the limited apparent host range of the latter.

  6. Defined α-synuclein prion-like molecular assemblies spreading in cell culture.

    Science.gov (United States)

    Aulić, Suzana; Le, Tran Thanh Nhat; Moda, Fabio; Abounit, Saïda; Corvaglia, Stefania; Casalis, Loredana; Gustincich, Stefano; Zurzolo, Chiara; Tagliavini, Fabrizio; Legname, Giuseppe

    2014-06-04

    α-Synuclein (α-syn) plays a central role in the pathogenesis of synucleinopathies, a group of neurodegenerative disorders that includes Parkinson disease, dementia with Lewy bodies and multiple system atrophy. Several findings from cell culture and mouse experiments suggest intercellular α-syn transfer. Through a methodology used to obtain synthetic mammalian prions, we tested whether recombinant human α-syn amyloids can promote prion-like accumulation in neuronal cell lines in vitro. A single exposure to amyloid fibrils of human α-syn was sufficient to induce aggregation of endogenous α-syn in human neuroblastoma SH-SY5Y cells. Remarkably, endogenous wild-type α-syn was sufficient for the formation of these aggregates, and overexpression of the protein was not required. Our results provide compelling evidence that endogenous α-syn can accumulate in cell culture after a single exposure to exogenous α-syn short amyloid fibrils. Importantly, using α-syn short amyloid fibrils as seed, endogenous α-syn aggregates and accumulates over several passages in cell culture, providing an excellent tool for potential therapeutic screening of pathogenic α-syn aggregates.

  7. A Genome Wide Association Study Links Glutamate Receptor Pathway to Sporadic Creutzfeldt-Jakob Disease Risk

    Science.gov (United States)

    Sanchez-Juan, Pascual; Bishop, Matthew T.; Kovacs, Gabor G.; Calero, Miguel; Aulchenko, Yurii S.; Ladogana, Anna; Boyd, Alison; Lewis, Victoria; Ponto, Claudia; Calero, Olga; Poleggi, Anna; Carracedo, Ángel; van der Lee, Sven J.; Ströbel, Thomas; Rivadeneira, Fernando; Hofman, Albert; Haïk, Stéphane; Combarros, Onofre; Berciano, José; Uitterlinden, Andre G.; Collins, Steven J.; Budka, Herbert; Brandel, Jean-Philippe; Laplanche, Jean Louis; Pocchiari, Maurizio; Zerr, Inga; Knight, Richard S. G.; Will, Robert G.; van Duijn, Cornelia M.

    2015-01-01

    We performed a genome-wide association (GWA) study in 434 sporadic Creutzfeldt-Jakob disease (sCJD) patients and 1939 controls from the United Kingdom, Germany and The Netherlands. The findings were replicated in an independent sample of 1109 sCJD and 2264 controls provided by a multinational consortium. From the initial GWA analysis we selected 23 SNPs for further genotyping in 1109 sCJD cases from seven different countries. Five SNPs were significantly associated with sCJD after correction for multiple testing. Subsequently these five SNPs were genotyped in 2264 controls. The pooled analysis, including 1543 sCJD cases and 4203 controls, yielded two genome wide significant results: rs6107516 (p-value=7.62x10-9) a variant tagging the prion protein gene (PRNP); and rs6951643 (p-value=1.66x10-8) tagging the Glutamate Receptor Metabotropic 8 gene (GRM8). Next we analysed the data stratifying by country of origin combining samples from the pooled analysis with genotypes from the 1000 Genomes Project and imputed genotypes from the Rotterdam Study (Total n=12967). The meta-analysis of the results showed that rs6107516 (p-value=3.00x10-8) and rs6951643 (p-value=3.91x10-5) remained as the two most significantly associated SNPs. Rs6951643 is located in an intronic region of GRM8, a gene that was additionally tagged by a cluster of 12 SNPs within our top100 ranked results. GRM8 encodes for mGluR8, a protein which belongs to the metabotropic glutamate receptor family, recently shown to be involved in the transduction of cellular signals triggered by the prion protein. Pathway enrichment analyses performed with both Ingenuity Pathway Analysis and ALIGATOR postulates glutamate receptor signalling as one of the main pathways associated with sCJD. In summary, we have detected GRM8 as a novel, non-PRNP, genome-wide significant marker associated with heightened disease risk, providing additional evidence supporting a role of glutamate receptors in sCJD pathogenesis. PMID:25918841

  8. Dietary factors and microsatellite instability in sporadic colon carcinomas

    NARCIS (Netherlands)

    Diergaarde, B.; Braam, H.; Muijen, van G.N.P.; Ligtenberg, M.J.L.; Kok, F.J.; Kampman, E.

    2003-01-01

    Microsatellite instability (MSI) occurs in 10-20% of the sporadic colon carcinomas and appears to be primarily due to alterations in hMLH1 and hMSH2. Little is known about the role of diet in MSI-related colon carcinogenesis. We used data from a Dutch population-based case-control study on sporadic

  9. Dietary factors and microsatellite instability in sporadic colon carcinomas.

    NARCIS (Netherlands)

    Diergaarde, B.; Braam, H.; Muijen, G.N.P. van; Ligtenberg, M.J.L.; Kok, F.J.; Kampman, E.

    2003-01-01

    Microsatellite instability (MSI) occurs in 10-20% of the sporadic colon carcinomas and appears to be primarily due to alterations in hMLH1 and hMSH2. Little is known about the role of diet in MSI-related colon carcinogenesis. We used data from a Dutch population-based case-control study on sporadic

  10. Sporadic Creutzfeldt-Jakob Disease (sCJD)

    Centers for Disease Control (CDC) Podcasts

    2009-02-03

    In this podcast, Dr. Lynne Sehulster discusses Creutzfeldt-Jakob disease, a rare neurodegenerative disease. This disease is caused by a pathological accumulation in the brain of an abnormal protein known as prions.  Created: 2/3/2009 by Emerging Infectious Diseases.   Date Released: 2/3/2009.

  11. Role of galectin-3 in prion infections of the CNS

    International Nuclear Information System (INIS)

    Mok, Simon W.F.; Riemer, Constanze; Madela, Kazimierz; Hsu, Daniel K.; Liu, Fu-Tong; Gueltner, Sandra; Heise, Ines; Baier, Michael

    2007-01-01

    Galectin-3 is a multi-functional protein and participates in mediating inflammatory reactions. The pronounced overexpression of galectin-3 in prion-infected brain tissue prompted us to study the role of this protein in a murine prion model. Immunofluorescence double-labelling identified microglia as the major cell type expressing galectin-3. Ablation of galectin-3 did not affect PrP Sc -deposition and development of gliosis. However, galectin-3 -/- -mice showed prolonged survival times upon intracerebral and peripheral scrapie infections. Moreover, protein levels of the lysosomal activation marker LAMP-2 were markedly reduced in prion-infected galectin-3 -/- -mice suggesting a role of galectin-3 in regulation of lysosomal functions. Lower mRNA levels of Beclin-1 and Atg5 in prion-infected wild-type and galectin-3 -/- -mice indicated an impairment of autophagy although autophagosome formation was unchanged. The results point towards a detrimental role of galectin-3 in prion infections of the CNS and suggest that endo-/lysosomal dysfunction in combination with reduced autophagy may contribute to disease development

  12. Structure-based view on [PSI(+)] prion properties.

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    Bondarev, Stanislav A; Zhouravleva, Galina A; Belousov, Mikhail V; Kajava, Andrey V

    2015-01-01

    Yeast [PSI(+)] prion is one of the most suitable and well characterized system for the investigation of the prion phenomenon. However, until recently, the lack of data on the 3D arrangement of Sup35p prion fibrils hindered progress in this area. The recent arrival in this field of new experimental techniques led to the parallel and in-register superpleated β-structure as a consensus model for Sup35p fibrils. Here, we analyzed the effect of amino acid substitutions of the Sup35 protein through the prism of this structural model. Application of a newly developed computational approach, called ArchCandy, gives us a better understanding of the effect caused by mutations on the fibril forming potential of Sup35 protein. This bioinformatics tool can be used for the design of new mutations with desired modification of prion properties. Thus, we provide examples of how today, having progress toward elucidation of the structural arrangement of Sup35p fibrils, researchers can advance more efficiently to a better understanding of prion [PSI(+)] stability and propagation.

  13. Yeast prion architecture explains how proteins can be genes

    Science.gov (United States)

    Wickner, Reed

    2013-03-01

    Prions (infectious proteins) transmit information without an accompanying DNA or RNA. Most yeast prions are self-propagating amyloids that inactivate a normally functional protein. A single protein can become any of several prion variants, with different manifestations due to different amyloid structures. We showed that the yeast prion amyloids of Ure2p, Sup35p and Rnq1p are folded in-register parallel beta sheets using solid state NMR dipolar recoupling experiments, mass-per-filament-length measurements, and filament diameter measurements. The extent of beta sheet structure, measured by chemical shifts in solid-state NMR and acquired protease-resistance on amyloid formation, combined with the measured filament diameters, imply that the beta sheets must be folded along the long axis of the filament. We speculate that prion variants of a single protein sequence differ in the location of these folds. Favorable interactions between identical side chains must hold these structures in-register. The same interactions must guide an unstructured monomer joining the end of a filament to assume the same conformation as molecules already in the filament, with the turns at the same locations. In this way, a protein can template its own conformation, in analogy to the ability of a DNA molecule to template its sequence by specific base-pairing. Bldg. 8, Room 225, NIH, 8 Center Drive MSC 0830, Bethesda, MD 20892-0830, wickner@helix.nih.gov, 301-496-3452

  14. Prion Fragment Peptides Are Digested with Membrane Type Matrix Metalloproteinases and Acquire Enzyme Resistance through Cu2+-Binding

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    Aya Kojima

    2014-05-01

    Full Text Available Prions are the cause of neurodegenerative disease in humans and other mammals. The structural conversion of the prion protein (PrP from a normal cellular protein (PrPC to a protease-resistant isoform (PrPSc is thought to relate to Cu2+ binding to histidine residues. In this study, we focused on the membrane-type matrix metalloproteinases (MT-MMPs such as MT1-MMP and MT3-MMP, which are expressed in the brain as PrPC-degrading proteases. We synthesized 21 prion fragment peptides. Each purified peptide was individually incubated with recombinant MT1-MMP or MT3-MMP in the presence or absence of Cu2+ and the cleavage sites determined by LC-ESI-MS analysis. Recombinant MMP-7 and human serum (HS were also tested as control. hPrP61-90, from the octapeptide-repeat region, was cleaved by HS but not by the MMPs tested here. On the other hand, hPrP92-168 from the central region was cleaved by MT1-MMP and MT3-MMP at various sites. These cleavages were inhibited by treatment with Cu2+. The C-terminal peptides had higher resistance than the central region. The data obtained from this study suggest that MT-MMPs expressed in the brain might possess PrPC-degrading activity.

  15. Semi-purification procedures of prions from a prion-infected brain using sucrose has no influence on the nonenzymatic glycation of the disease-associated prion isoform.

    Science.gov (United States)

    Choi, Yeong-Gon; Kim, Jae-Il; Choi, Eun-Kyoung; Carp, Richard I; Kim, Yong-Sun

    2016-01-01

    Previous studies have shown that the Nε-carboxymethyl group is linked to not only one or more N-terminal Lys residues but also to one or more Lys residues of the protease-resistant core region of the pathogenic prion isoform (PrPSc) in prion-infected brains. Using an anti-advanced glycation end product (AGE) antibody, we detected nonenzymatically glycated PrPSc (AGE-PrPSc) in prion-infected brains following concentration by a series of ultracentrifugation steps with a sucrose cushion. In the present study, the levels of in vitro nonenzymatic glycation of PrPSc using sucrose were investigated to determine whether sucrose cushion can artificially and nonenzymatically induce in vitro glycation during ultracentrifugation. The first insoluble pellet fraction following the first ultracentrifugation (PU1st) collected from 263K scrapie-infected brains was incubated with sucrose, glucose or colloidal silica coated with polyvinylpyrrolidone (percoll). None of the compounds in vitro resulted in AGE-PrPSc. Nonetheless, glucose and percoll produced AGEs in vitro from other proteins within PU1st of the infected brains. This reaction could lead to the AGE-modified polymer(s) of nonenzymatic glycation-prone protein(s). This study showed that PrPSc is not nonenzymatically glycated in vitro with sucrose, glucose or percoll and that AGE-modified PrPSc can be isolated and enriched from prion-infected brains.

  16. Protein misfolding cyclic amplification induces the conversion of recombinant prion protein to PrP oligomers causing neuronal apoptosis.

    Science.gov (United States)

    Yuan, Zhen; Yang, Lifeng; Chen, Baian; Zhu, Ting; Hassan, Mohammad Farooque; Yin, Xiaomin; Zhou, Xiangmei; Zhao, Deming

    2015-06-01

    The formation of neurotoxic prion protein (PrP) oligomers is thought to be a key step in the development of prion diseases. Recently, it was determined that the sonication and shaking of recombinant PrP can convert PrP monomers into β-state oligomers. Herein, we demonstrate that β-state oligomeric PrP can be generated through protein misfolding cyclic amplification from recombinant full-length hamster, human, rabbit, and mutated rabbit PrP, and that these oligomers can be used for subsequent research into the mechanisms of PrP-induced neurotoxicity. We have characterized protein misfolding cyclic amplification-induced monomer-to-oligomer conversion of PrP from three species using western blotting, circular dichroism, size-exclusion chromatography, and resistance to proteinase K (PK) digestion. We have further shown that all of the resulting β-oligomers are toxic to primary mouse cortical neurons independent of the presence of PrP(C) in the neurons, whereas the corresponding monomeric PrP were not toxic. In addition, we found that this toxicity is the result of oligomer-induced apoptosis via regulation of Bcl-2, Bax, and caspase-3 in both wild-type and PrP(-/-) cortical neurons. It is our hope that these results may contribute to our understanding of prion transformation within the brain. We found that β-state oligomeric PrPs can be generated through protein misfolding cyclic amplification (PMCA) from recombinant full-length hamster, human, rabbit, and mutated rabbit PrP. β-oligomers are toxic to primary mouse cortical neurons independent of the presence of PrP(C) in the neurons, while the corresponding monomeric PrPs were not toxic. This toxicity is the result of oligomers-induced apoptosis via regulation of Bcl-2, Bax, and caspase-3. These results may contribute to our understanding of prion transformation within the brain. © 2015 International Society for Neurochemistry.

  17. A simple, versatile and sensitive cell-based assay for prions from various species.

    Directory of Open Access Journals (Sweden)

    Zaira E Arellano-Anaya

    Full Text Available Detection and quantification of prion infectivity is a crucial step for various fundamental and applied aspects of prion research. Identification of cell lines highly sensitive to prion infection led to the development of cell-based titration procedures aiming at replacing animal bioassays, usually performed in mice or hamsters. However, most of these cell lines are only permissive to mouse-adapted prions strains and do not allow titration of prions from other species. In this study, we show that epithelial RK13, a cell line permissive to mouse and bank vole prion strains and to natural prion agents from sheep and cervids, enables a robust and sensitive detection of mouse and ovine-derived prions. Importantly, the cell culture work is strongly reduced as the RK13 cell assay procedure designed here does not require subcultivation of the inoculated cultures. We also show that prions effectively bind to culture plastic vessel and are quantitatively detected by the cell assay. The possibility to easily quantify a wider range of prions, including rodent experimental strains but also natural agents from sheep and cervids, should prompt the spread of cell assays for routine prion titration and lead to valuable information in fundamental and applied studies.

  18. Patterns of [PSI+] aggregation allow insights into cellular organization of yeast prion aggregates

    Science.gov (United States)

    Tyedmers, Jens

    2012-01-01

    The yeast prion phenomenon is very widespread and mounting evidence suggests that it has an impact on cellular regulatory mechanisms related to phenotypic responses to changing environments. Studying the aggregation patterns of prion amyloids during different stages of the prion life cycle is a first key step to understand major principles of how and where cells generate, organize and turn-over prion aggregates. The induction of the [PSI+] state involves the actin cytoskeleton and quality control compartments such as the Insoluble Protein Deposit (IPOD). An initially unstable transitional induction state can be visualized by overexpression of the prion determinant and displays characteristic large ring- and ribbon-shaped aggregates consisting of poorly fragmented bundles of very long prion fibrils. In the mature prion state, the aggregation pattern is characterized by highly fragmented, shorter prion fibrils that form aggregates, which can be visualized through tagging with fluorescent proteins. The number of aggregates formed varies, ranging from a single large aggregate at the IPOD to multiple smaller ones, depending on several parameters discussed. Aggregate units below the resolution of light microscopy that are detectable by fluorescence correlation spectroscopy are in equilibrium with larger aggregates in this stage and can mediate faithful inheritance of the prion state. Loss of the prion state is often characterized by reduced fragmentation of prion fibrils and fewer, larger aggregates. PMID:22449721

  19. Ascertainment bias causes false signal of anticipation in genetic prion disease.

    Science.gov (United States)

    Minikel, Eric Vallabh; Zerr, Inga; Collins, Steven J; Ponto, Claudia; Boyd, Alison; Klug, Genevieve; Karch, André; Kenny, Joanna; Collinge, John; Takada, Leonel T; Forner, Sven; Fong, Jamie C; Mead, Simon; Geschwind, Michael D

    2014-10-02

    Anticipation is the phenomenon whereby age of onset in genetic disease decreases in successive generations. Three independent reports have claimed anticipation in Creutzfeldt-Jakob disease (CJD) caused by the c.598G > A mutation in PRNP encoding a p.Glu200Lys (E200K) substitution in the prion protein. If confirmed, this finding would carry clear implications for genetic counseling. We analyzed pedigrees with this mutation from four prion centers worldwide (n = 217 individuals with the mutation) to analyze age of onset and death in affected and censored individuals. We show through simulation that selective ascertainment of individuals whose onset falls within the historical window since the mutation's 1989 discovery is sufficient to create robust false signals both of anticipation and of heritability of age of onset. In our data set, the number of years of anticipation observed depends upon how strictly the data are limited by the ascertainment window. Among individuals whose disease was directly observed at a study center, a 28-year difference between parent and child age of onset is observed (p = 0.002), but including individuals ascertained retrospectively through family history reduces this figure to 7 years (p = 0.005). Applying survival analysis to the most thoroughly ascertained subset of data eliminates the signal of anticipation. Moreover, even non-CJD deaths exhibit 16 years anticipation (p = 0.002), indicating that ascertainment bias can entirely explain observed anticipation. We suggest that reports of anticipation in genetic prion disease are driven entirely by ascertainment bias. Guidelines for future studies claiming statistical evidence for anticipation are suggested. Copyright © 2014 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  20. Disease Transmission by Misfolded Prion-Protein Isoforms, Prion-Like Amyloids, Functional Amyloids and the Central Dogma

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    Martin L. Daus

    2016-01-01

    Full Text Available In 1982, the term “prions” (proteinaceous infectious particles was coined to specify a new principle of infection. A misfolded isoform of a cellular protein has been described as the causative agent of a fatal neurodegenerative disease. At the beginning of prion research scientists assumed that the infectious agent causing transmissible spongiform encephalopathy (TSE was a virus, but some unconventional properties of these pathogens were difficult to bring in line with the prevailing viral model. The discovery that prions (obviously devoid of any coding nucleic acid can store and transmit information similarly to DNA was initially even denoted as being “heretical” but is nowadays mainly accepted by the scientific community. This review describes, from a historical point of view, how the “protein-only hypothesis” expands the Central Dogma. Definition of both, the prion principle and the Central Dogma, have been essential steps to understand information storage and transfer within and among cells and organisms. Furthermore, the current understanding of the infectivity of prion-proteins after misfolding is summarized succinctly. Finally, prion-like amyloids and functional amyloids, as found in yeast and bacteria, will be discussed.

  1. Fungal prion HET-s as a model for structural complexity and self-propagation in prions.

    Science.gov (United States)

    Wan, William; Stubbs, Gerald

    2014-04-08

    The highly ordered and reproducible structure of the fungal prion HET-s makes it an excellent model system for studying the inherent properties of prions, self-propagating infectious proteins that have been implicated in a number of fatal diseases. In particular, the HET-s prion-forming domain readily folds into a relatively complex two-rung β-solenoid amyloid. The faithful self-propagation of this fold involves a diverse array of inter- and intramolecular structural features. These features include a long flexible loop connecting the two rungs, buried polar residues, salt bridges, and asparagine ladders. We have used site-directed mutagenesis and X-ray fiber diffraction to probe the relative importance of these features for the formation of β-solenoid structure, as well as the cumulative effects of multiple mutations. Using fibrillization kinetics and chemical stability assays, we have determined the biophysical effects of our mutations on the assembly and stability of the prion-forming domain. We have found that a diversity of structural features provides a level of redundancy that allows robust folding and stability even in the face of significant sequence alterations and suboptimal environmental conditions. Our findings provide fundamental insights into the structural interactions necessary for self-propagation. Propagation of prion structure seems to require an obligatory level of complexity that may not be reproducible in short peptide models.

  2. Comparative analysis of the prion protein gene sequences in African lion.

    Science.gov (United States)

    Wu, Chang-De; Pang, Wan-Yong; Zhao, De-Ming

    2006-10-01

    The prion protein gene of African lion (Panthera Leo) was first cloned and polymorphisms screened. The results suggest that the prion protein gene of eight African lions is highly homogenous. The amino acid sequences of the prion protein (PrP) of all samples tested were identical. Four single nucleotide polymorphisms (C42T, C81A, C420T, T600C) in the prion protein gene (Prnp) of African lion were found, but no amino acid substitutions. Sequence analysis showed that the higher homology is observed to felis catus AF003087 (96.7%) and to sheep number M31313.1 (96.2%) Genbank accessed. With respect to all the mammalian prion protein sequences compared, the African lion prion protein sequence has three amino acid substitutions. The homology might in turn affect the potential intermolecular interactions critical for cross species transmission of prion disease.

  3. Follicular dendritic cell-specific prion protein (PrP expression alone is sufficient to sustain prion infection in the spleen.

    Directory of Open Access Journals (Sweden)

    Laura McCulloch

    2011-12-01

    Full Text Available Prion diseases are characterised by the accumulation of PrP(Sc, an abnormally folded isoform of the cellular prion protein (PrP(C, in affected tissues. Following peripheral exposure high levels of prion-specific PrP(Sc accumulate first upon follicular dendritic cells (FDC in lymphoid tissues before spreading to the CNS. Expression of PrP(C is mandatory for cells to sustain prion infection and FDC appear to express high levels. However, whether FDC actively replicate prions or simply acquire them from other infected cells is uncertain. In the attempts to-date to establish the role of FDC in prion pathogenesis it was not possible to dissociate the Prnp expression of FDC from that of the nervous system and all other non-haematopoietic lineages. This is important as FDC may simply acquire prions after synthesis by other infected cells. To establish the role of FDC in prion pathogenesis transgenic mice were created in which PrP(C expression was specifically "switched on" or "off" only on FDC. We show that PrP(C-expression only on FDC is sufficient to sustain prion replication in the spleen. Furthermore, prion replication is blocked in the spleen when PrP(C-expression is specifically ablated only on FDC. These data definitively demonstrate that FDC are the essential sites of prion replication in lymphoid tissues. The demonstration that Prnp-ablation only on FDC blocked splenic prion accumulation without apparent consequences for FDC status represents a novel opportunity to prevent neuroinvasion by modulation of PrP(C expression on FDC.

  4. Humic substances interfere with detection of pathogenic prion protein

    Science.gov (United States)

    Smith, Christen B.; Booth, Clarissa J.; Wadzinski, Tyler J.; Legname, Giuseppe; Chappell, Rick; Johnson, Christopher J.; Pedersen, Joel A.

    2014-01-01

    Studies examining the persistence of prions (the etiological agent of transmissible spongiform encephalopathies) in soil require accurate quantification of pathogenic prion protein (PrPTSE) extracted from or in the presence of soil particles. Here, we demonstrate that natural organic matter (NOM) in soil impacts PrPTSE detection by immunoblotting. Methods commonly used to extract PrPTSE from soils release substantial amounts of NOM, and NOM inhibited PrPTSE immunoblot signal. The degree of immunoblot interference increased with increasing NOM concentration and decreasing NOM polarity. Humic substances affected immunoblot detection of prion protein from both deer and hamsters. We also establish that after interaction with humic acid, PrPTSE remains infectious to hamsters inoculated intracerebrally, and humic acid appeared to slow disease progression. These results provide evidence for interactions between PrPTSE and humic substances that influence both accurate measurement of PrPTSE in soil and disease transmission.

  5. Analysis of nucleic acid chaperoning by the prion protein and its inhibition by oligonucleotides.

    Science.gov (United States)

    Guichard, Cécile; Ivanyi-Nagy, Roland; Sharma, Kamal Kant; Gabus, Caroline; Marc, Daniel; Mély, Yves; Darlix, Jean-Luc

    2011-10-01

    Prion diseases are unique neurodegenerative illnesses associated with the conversion of the cellular prion protein (PrP(C)) into the aggregated misfolded scrapie isoform, named PrP(Sc). Recent studies on the physiological role of PrP(C) revealed that this protein has probably multiple functions, notably in cell-cell adhesion and signal transduction, and in assisting nucleic acid folding. In fact, in vitro findings indicated that the human PrP (huPrP) possesses nucleic acid binding and annealing activities, similarly to nucleic acid chaperone proteins that play essential roles in cellular DNA and RNA metabolism. Here, we show that a peptide, representing the N-terminal domain of huPrP, facilitates nucleic acid annealing by two parallel pathways nucleated through the stem termini. We also show that PrP of human or ovine origin facilitates DNA strand exchange, ribozyme-directed cleavage of an RNA template and RNA trans-splicing in a manner similar to the nucleocapsid protein of HIV-1. In an attempt to characterize inhibitors of PrP-chaperoning in vitro we discovered that the thioaptamer 5'-GACACAAGCCGA-3' was extensively inhibiting the PrP chaperoning activities. At the same time a recently characterized methylated oligoribonucleotide inhibiting the chaperoning activity of the HIV-1 nucleocapsid protein was poorly impairing the PrP chaperoning activities.

  6. Disrupting the cortical actin cytoskeleton points to two distinct mechanisms of yeast [PSI+] prion formation

    Science.gov (United States)

    Speldewinde, Shaun H.; Tuite, Mick F.

    2017-01-01

    Mammalian and fungal prions arise de novo; however, the mechanism is poorly understood in molecular terms. One strong possibility is that oxidative damage to the non-prion form of a protein may be an important trigger influencing the formation of its heritable prion conformation. We have examined the oxidative stress-induced formation of the yeast [PSI+] prion, which is the altered conformation of the Sup35 translation termination factor. We used tandem affinity purification (TAP) and mass spectrometry to identify the proteins which associate with Sup35 in a tsa1 tsa2 antioxidant mutant to address the mechanism by which Sup35 forms the [PSI+] prion during oxidative stress conditions. This analysis identified several components of the cortical actin cytoskeleton including the Abp1 actin nucleation promoting factor, and we show that deletion of the ABP1 gene abrogates oxidant-induced [PSI+] prion formation. The frequency of spontaneous [PSI+] prion formation can be increased by overexpression of Sup35 since the excess Sup35 increases the probability of forming prion seeds. In contrast to oxidant-induced [PSI+] prion formation, overexpression-induced [PSI+] prion formation was only modestly affected in an abp1 mutant. Furthermore, treating yeast cells with latrunculin A to disrupt the formation of actin cables and patches abrogated oxidant-induced, but not overexpression-induced [PSI+] prion formation, suggesting a mechanistic difference in prion formation. [PIN+], the prion form of Rnq1, localizes to the IPOD (insoluble protein deposit) and is thought to influence the aggregation of other proteins. We show Sup35 becomes oxidized and aggregates during oxidative stress conditions, but does not co-localize with Rnq1 in an abp1 mutant which may account for the reduced frequency of [PSI+] prion formation. PMID:28369054

  7. Differentially expressed genes in iron-induced prion protein conversion

    International Nuclear Information System (INIS)

    Kim, Minsun; Kim, Eun-hee; Choi, Bo-Ran; Woo, Hee-Jong

    2016-01-01

    The conversion of the cellular prion protein (PrP C ) to the protease-resistant isoform is the key event in chronic neurodegenerative diseases, including transmissible spongiform encephalopathies (TSEs). Increased iron in prion-related disease has been observed due to the prion protein-ferritin complex. Additionally, the accumulation and conversion of recombinant PrP (rPrP) is specifically derived from Fe(III) but not Fe(II). Fe(III)-mediated PK-resistant PrP (PrP res ) conversion occurs within a complex cellular environment rather than via direct contact between rPrP and Fe(III). In this study, differentially expressed genes correlated with prion degeneration by Fe(III) were identified using Affymetrix microarrays. Following Fe(III) treatment, 97 genes were differentially expressed, including 85 upregulated genes and 12 downregulated genes (≥1.5-fold change in expression). However, Fe(II) treatment produced moderate alterations in gene expression without inducing dramatic alterations in gene expression profiles. Moreover, functional grouping of identified genes indicated that the differentially regulated genes were highly associated with cell growth, cell maintenance, and intra- and extracellular transport. These findings showed that Fe(III) may influence the expression of genes involved in PrP folding by redox mechanisms. The identification of genes with altered expression patterns in neural cells may provide insights into PrP conversion mechanisms during the development and progression of prion-related diseases. - Highlights: • Differential genes correlated with prion degeneration by Fe(III) were identified. • Genes were identified in cell proliferation and intra- and extracellular transport. • In PrP degeneration, redox related genes were suggested. • Cbr2, Rsad2, Slc40a1, Amph and Mvd were expressed significantly.

  8. Prion propagation in cells expressing PrP glycosylation mutants.

    Science.gov (United States)

    Salamat, Muhammad K; Dron, Michel; Chapuis, Jérôme; Langevin, Christelle; Laude, Hubert

    2011-04-01

    Infection by prions involves conversion of a host-encoded cell surface protein (PrP(C)) to a disease-related isoform (PrP(Sc)). PrP(C) carries two glycosylation sites variably occupied by complex N-glycans, which have been suggested by previous studies to