1
|
Sola D, Betancor M, Marco Lorente PA, Pérez Lázaro S, Barrio T, Sevilla E, Marín B, Moreno B, Monzón M, Acín C, Bolea R, Badiola JJ, Otero A. Diagnosis in Scrapie: Conventional Methods and New Biomarkers. Pathogens 2023; 12:1399. [PMID: 38133284 PMCID: PMC10746075 DOI: 10.3390/pathogens12121399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/24/2023] [Accepted: 11/24/2023] [Indexed: 12/23/2023] Open
Abstract
Scrapie, a naturally occurring prion disease affecting goats and sheep, comprises classical and atypical forms, with classical scrapie being the archetype of transmissible spongiform encephalopathies. This review explores the challenges of scrapie diagnosis and the utility of various biomarkers and their potential implications for human prion diseases. Understanding these biomarkers in the context of scrapie may enable earlier prion disease diagnosis in humans, which is crucial for effective intervention. Research on scrapie biomarkers bridges the gap between veterinary and human medicine, offering hope for the early detection and improved management of prion diseases.
Collapse
Affiliation(s)
- Diego Sola
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Marina Betancor
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Paula A. Marco Lorente
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Sonia Pérez Lázaro
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Tomás Barrio
- Unité Mixte de Recherche de l’Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement1225 Interactions Hôtes-Agents Pathogènes, École Nationale Vétérinaire de Toulouse, 31076 Toulouse, France
| | - Eloisa Sevilla
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Belén Marín
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Bernardino Moreno
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Marta Monzón
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Cristina Acín
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Rosa Bolea
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Juan J. Badiola
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| | - Alicia Otero
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, IA2, Universidad de Zaragoza, 50013 Zaragoza, Spain; (D.S.)
| |
Collapse
|
2
|
Carroll JA, Striebel JF, Baune C, Chesebro B, Race B. CD11c is not required by microglia to convey neuroprotection after prion infection. PLoS One 2023; 18:e0293301. [PMID: 37910561 PMCID: PMC10619787 DOI: 10.1371/journal.pone.0293301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 10/10/2023] [Indexed: 11/03/2023] Open
Abstract
Prion diseases are caused by the misfolding of a normal host protein that leads to gliosis, neuroinflammation, neurodegeneration, and death. Microglia have been shown to be critical for neuroprotection during prion infection of the central nervous system (CNS), and their presence extends survival in mice. How microglia impart these benefits to the infected host are unknown. Previous transcriptomics and bioinformatics studies suggested that signaling through the heterodimeric integrin receptor CD11c/CD18, expressed by microglia in the brain, might be important to microglial function during prion disease. Herein, we intracerebrally challenged CD11c-/- mice with prion strain RML and compared them to similarly infected C57BL/6 mice as controls. We initially assessed changes in the brain that are associated with disease such as astrogliosis, microgliosis, prion accumulation, and survival. Targeted qRT-PCR arrays were used to determine alterations in transcription in mice in response to prion infection. We demonstrate that expression of Itgax (CD11c) and Itgb2 (CD18) increases in the CNS in correlation with advancing prion infection. Gliosis, neuropathology, prion deposition, and disease progression in prion infected CD11c deficient mice were comparable to infected C57BL/6 mice. Additionally, both CD11c deficient and C57BL/6 prion-infected mouse cohorts had a similar consortium of inflammatory- and phagocytosis-associated genes that increased as disease progressed to clinical stages. Ingenuity Pathway Analysis of upregulated genes in infected C57BL/6 mice suggested numerous cell-surface transmembrane receptors signal through Spleen Tyrosine Kinase, a potential key regulator of phagocytosis and innate immune activation in the prion infected brain. Ultimately, the deletion of CD11c did not influence prion pathogenesis in mice and CD11c signaling is not involved in the neuroprotection provided by microglia, but our analysis identified a conspicuous phagocytosis pathway in the CNS of infected mice that appeared to be activated during prion pathogenesis.
Collapse
Affiliation(s)
- James A. Carroll
- Laboratory of Neurological Infections and Immunity, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - James F. Striebel
- Laboratory of Neurological Infections and Immunity, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Chase Baune
- Laboratory of Neurological Infections and Immunity, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Bruce Chesebro
- Laboratory of Neurological Infections and Immunity, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Brent Race
- Laboratory of Neurological Infections and Immunity, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| |
Collapse
|
3
|
Race B, Williams K, Baune C, Striebel JF, Long D, Thomas T, Lubke L, Chesebro B, Carroll JA. Microglia have limited influence on early prion pathogenesis, clearance, or replication. PLoS One 2022; 17:e0276850. [PMID: 36301895 PMCID: PMC9612458 DOI: 10.1371/journal.pone.0276850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 10/14/2022] [Indexed: 11/07/2022] Open
Abstract
Microglia (MG) are critical to host defense during prion infection, but the mechanism(s) of this neuroprotection are poorly understood. To better examine the influence of MG during prion infection, we reduced MG in the brains of C57BL/10 mice using PLX5622 and assessed prion clearance and replication using multiple approaches that included bioassay, immunohistochemistry, and Real-Time Quaking Inducted Conversion (RT-QuIC). We also utilized a strategy of intermittent PLX5622 treatments to reduce MG and allow MG repopulation to test whether new MG could alter prion disease progress. Lastly, we investigated the influence of MG using tga20 mice, a rapid prion model that accumulates fewer pathological features and less PrPres in the infected brain. In C57BL/10 mice we found that MG were excluded from the inoculation site early after infection, but Iba1 positive infiltrating monocytes/macrophage were present. Reducing MG in the brain prior to prion inoculation did not increase susceptibility to prion infection. Short intermittent treatments with PLX5622 in prion infected C57BL/10 mice after 80 dpi were unsuccessful at altering the MG population, gliosis, or survival. Additionally, MG depletion using PLX5622 in tga20 mice had only a minor impact on prion pathogenesis, indicating that the presence of MG might be less important in this fast model with less prion accumulation. In contrast to the benefits of MG against prion disease in late stages of disease, our current experiments suggest MG do not play a role in early prion pathogenesis, clearance, or replication.
Collapse
Affiliation(s)
- Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail: (BR); (JAC)
| | - Katie Williams
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Chase Baune
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - James F. Striebel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Dan Long
- Rocky Mountain Veterinary Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Tina Thomas
- Rocky Mountain Veterinary Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Lori Lubke
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - James A. Carroll
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail: (BR); (JAC)
| |
Collapse
|
4
|
Mercer RCC, Harris DA. Mechanisms of prion-induced toxicity. Cell Tissue Res 2022; 392:81-96. [PMID: 36070155 DOI: 10.1007/s00441-022-03683-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/30/2022] [Indexed: 11/02/2022]
Abstract
Prion diseases are devastating neurodegenerative diseases caused by the structural conversion of the normally benign prion protein (PrPC) to an infectious, disease-associated, conformer, PrPSc. After decades of intense research, much is known about the self-templated prion conversion process, a phenomenon which is now understood to be operative in other more common neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. In this review, we provide the current state of knowledge concerning a relatively poorly understood aspect of prion diseases: mechanisms of neurotoxicity. We provide an overview of proposed functions of PrPC and its interactions with other extracellular proteins in the central nervous system, in vivo and in vitro models used to delineate signaling events downstream of prion propagation, the application of omics technologies, and the emerging appreciation of the role played by non-neuronal cell types in pathogenesis.
Collapse
Affiliation(s)
- Robert C C Mercer
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, USA
| | - David A Harris
- Department of Biochemistry, Boston University School of Medicine, Boston, MA, USA.
| |
Collapse
|
5
|
Mice Treated Subcutaneously with Mouse LPS-Converted PrP res or LPS Alone Showed Brain Gene Expression Profiles Characteristic of Prion Disease. Vet Sci 2021; 8:vetsci8090200. [PMID: 34564594 PMCID: PMC8473295 DOI: 10.3390/vetsci8090200] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/17/2021] [Accepted: 09/18/2021] [Indexed: 11/16/2022] Open
Abstract
Previously, we showed that bacterial lipopolysaccharide (LPS) converts mouse PrPC protein to a beta-rich isoform (moPrPres) resistant to proteinase K. In this study, we aimed to test if the LPS-converted PrPres is infectious and alters the expression of genes related to prion pathology in brains of terminally sick mice. Ninety female FVB/N mice at 5 weeks of age were randomly assigned to 6 groups treated subcutaneously (sc) for 6 weeks either with: (1) Saline (CTR); (2) LPS from Escherichia coli 0111:B4 (LPS), (3) one-time sc administration of de novo generated mouse recombinant prion protein (moPrP; 29-232) rich in beta-sheet by incubation with LPS (moPrPres), (4) LPS plus one-time sc injection of moPrPres, (5) one-time sc injection of brain homogenate from Rocky Mountain Lab (RLM) scrapie strain, and (6) LPS plus one-time sc injection of RML. Results showed that all treatments altered the expression of various genes related to prion disease and neuroinflammation starting at 11 weeks post-infection and more profoundly at the terminal stage. In conclusion, sc administration of de novo generated moPrPres, LPS, and a combination of moPrPres with LPS were able to alter the expression of multiple genes typical of prion pathology and inflammation.
Collapse
|
6
|
Regional Differences in Neuroinflammation-Associated Gene Expression in the Brain of Sporadic Creutzfeldt-Jakob Disease Patients. Int J Mol Sci 2020; 22:ijms22010140. [PMID: 33375642 PMCID: PMC7795938 DOI: 10.3390/ijms22010140] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 01/15/2023] Open
Abstract
Neuroinflammation is an essential part of neurodegeneration. Yet, the current understanding of neuroinflammation-associated molecular events in distinct brain regions of prion disease patients is insufficient to lay the ground for effective treatment strategies targeting this complex neuropathological process. To address this problem, we analyzed the expression of 800 neuroinflammation-associated genes to create a profile of biological processes taking place in the frontal cortex and cerebellum of patients who suffered from sporadic Creutzfeldt-Jakob disease. The analysis was performed using NanoString nCounter technology with human neuroinflammation panel+. The observed gene expression patterns were regionally and sub-regionally distinct, suggesting a variable neuroinflammatory response. Interestingly, the observed differences could not be explained by the molecular subtypes of sporadic Creutzfeldt-Jakob disease. Furthermore, analyses of canonical pathways and upstream regulators based on differentially expressed genes indicated an overlap between biological processes taking place in different brain regions. This suggests that even smaller-scale spatial data reflecting subtle changes in brain cells' functional heterogeneity and their immediate pathologic microenvironments are needed to explain the observed differential gene expression in a greater detail.
Collapse
|
7
|
Carroll JA, Race B, Williams K, Striebel J, Chesebro B. RNA-seq and network analysis reveal unique glial gene expression signatures during prion infection. Mol Brain 2020; 13:71. [PMID: 32381108 PMCID: PMC7206698 DOI: 10.1186/s13041-020-00610-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 04/24/2020] [Indexed: 02/01/2023] Open
Abstract
Background Prion diseases and prion-like disorders, including Alzheimer’s disease and Parkinson’s disease, are characterized by gliosis and accumulation of misfolded aggregated host proteins. Ablating microglia in prion-infected brain by treatment with the colony-stimulating factor-1 receptor (CSF-1R) inhibitor, PLX5622, increased accumulation of misfolded prion protein and decreased survival time. Methods To better understand the role of glia during neurodegeneration, we used RNA-seq technology, network analysis, and hierarchical cluster analysis to compare gene expression in brains of prion-infected versus mock-inoculated mice. Comparisons were also made between PLX5622-treated prion-infected mice and untreated prion-infected mice to assess mechanisms involved in disease acceleration in the absence of microglia. Results RNA-seq and network analysis suggested that microglia responded to prion infection through activation of integrin CD11c/18 and did not adopt the expression signature associated with other neurodegenerative disease models. Instead, microglia acquired an alternative molecular signature late in the disease process. Furthermore, astrocytes expressed a signature pattern of genes which appeared to be specific for prion diseases. Comparisons were also made with prion-infected mice treated with PLX5622 to assess the impact of microglia ablation on astrocyte gene expression during prion infection. In the presence of microglia, a unique mix of transcripts associated with A1- and A2-reactive astrocytes was increased in brains of prion-infected mice. After ablation of microglia, this reactive astrocyte expression pattern was enhanced. Thus, after prion infection, microglia appeared to decrease the overall A1/A2-astrocyte responses which might contribute to increased survival after infection. Conclusions RNA-seq analysis indicated dysregulation of over 300 biological processes within the CNS during prion disease. Distinctive microglia- and astrocyte-associated expression signatures were identified during prion infection. Furthermore, astrogliosis and the unique astrocyte-associated expression signature were independent of microglial influences. Astrogliosis and the unique astrocyte-associated gene expression pattern were increased when microglia were ablated. Our findings emphasize the potential existence of alternative pathways for activating the A1/A2 paradigm in astrocytes during neurodegenerative disease.
Collapse
Affiliation(s)
- James A Carroll
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South Fourth Street, Hamilton, MT, 59840, USA.
| | - Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South Fourth Street, Hamilton, MT, 59840, USA
| | - Katie Williams
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South Fourth Street, Hamilton, MT, 59840, USA
| | - James Striebel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South Fourth Street, Hamilton, MT, 59840, USA
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South Fourth Street, Hamilton, MT, 59840, USA
| |
Collapse
|
8
|
Majer A, Medina SJ, Sorensen D, Martin MJ, Frost KL, Phillipson C, Manguiat K, Booth SA. The cell type resolved mouse transcriptome in neuron-enriched brain tissues from the hippocampus and cerebellum during prion disease. Sci Rep 2019; 9:1099. [PMID: 30705335 PMCID: PMC6355796 DOI: 10.1038/s41598-018-37715-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 12/12/2018] [Indexed: 01/10/2023] Open
Abstract
Multiple cell types and complex connection networks are an intrinsic feature of brain tissue. In this study we used expression profiling of specific microscopic regions of heterogeneous tissue sections isolated by laser capture microdissection (LCM) to determine insights into the molecular basis of brain pathology in prion disease. Temporal profiles in two mouse models of prion disease, bovine spongiform encephalopathy (BSE) and a mouse-adapted strain of scrapie (RML) were performed in microdissected regions of the CA1 hippocampus and granular layer of the cerebellum which are both enriched in neuronal cell bodies. We noted that during clinical disease the number of activated microglia and astrocytes that occur in these areas are increased, thereby likely diluting the neuronal gene expression signature. We performed a comparative analysis with gene expression profiles determined from isolated populations of neurons, microglia and astrocytes to identify transcripts that are enriched in each of these cell types. Although the incubation periods of these two models are quite different, over 300 days for BSE and ~160 days for RML scrapie, these regional microdissections revealed broadly similar profiles. Microglial and astrocyte-enriched genes contributed a profound inflammatory profile consisting of inflammatory cytokines, genes related to phagocytosis, proteolysis and genes coding for extracellular matrix proteins. CA1 pyramidal neurons displayed a net upregulation of transcription factors and stress induced genes at pre-clinical stages of disease while all tissues showed profound decrease of overlapping genes related to neuronal function, in particular transcripts related to neuronal communication including glutamate receptors, phosphatase subunits and numerous synapse-related markers. Of note, we found a small number of genes expressed in neurons that were upregulated during clinical disease including, COX6A2, FZD9, RXRG and SOX11, that may be biomarkers of neurodegeneration.
Collapse
Affiliation(s)
- Anna Majer
- Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.,Viral Diseases, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Sarah J Medina
- Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Debra Sorensen
- Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Matthew J Martin
- Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.,Department of Medical Microbiology and Infectious Diseases, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Kathy L Frost
- Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Clark Phillipson
- Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Kathy Manguiat
- Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | - Stephanie A Booth
- Zoonotic Diseases and Special Pathogens, National Microbiology Laboratory, Canadian Science Centre for Human and Animal Health, Public Health Agency of Canada, Winnipeg, Manitoba, Canada. .,Department of Medical Microbiology and Infectious Diseases, College of Medicine, Faculty of Health Sciences, University of Manitoba, Winnipeg, Manitoba, Canada.
| |
Collapse
|
9
|
Neuroinflammation, Microglia, and Cell-Association during Prion Disease. Viruses 2019; 11:v11010065. [PMID: 30650564 PMCID: PMC6356204 DOI: 10.3390/v11010065] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 01/09/2019] [Accepted: 01/10/2019] [Indexed: 02/06/2023] Open
Abstract
Prion disorders are transmissible diseases caused by a proteinaceous infectious agent that can infect the lymphatic and nervous systems. The clinical features of prion diseases can vary, but common hallmarks in the central nervous system (CNS) are deposition of abnormally folded protease-resistant prion protein (PrPres or PrPSc), astrogliosis, microgliosis, and neurodegeneration. Numerous proinflammatory effectors expressed by astrocytes and microglia are increased in the brain during prion infection, with many of them potentially damaging to neurons when chronically upregulated. Microglia are important first responders to foreign agents and damaged cells in the CNS, but these immune-like cells also serve many essential functions in the healthy CNS. Our current understanding is that microglia are beneficial during prion infection and critical to host defense against prion disease. Studies indicate that reduction of the microglial population accelerates disease and increases PrPSc burden in the CNS. Thus, microglia are unlikely to be a foci of prion propagation in the brain. In contrast, neurons and astrocytes are known to be involved in prion replication and spread. Moreover, certain astrocytes, such as A1 reactive astrocytes, have proven neurotoxic in other neurodegenerative diseases, and thus might also influence the progression of prion-associated neurodegeneration.
Collapse
|
10
|
Carroll JA, Race B, Williams K, Chesebro B. Toll-like receptor 2 confers partial neuroprotection during prion disease. PLoS One 2018; 13:e0208559. [PMID: 30596651 PMCID: PMC6312208 DOI: 10.1371/journal.pone.0208559] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 11/19/2018] [Indexed: 02/07/2023] Open
Abstract
Neuroinflammation and neurodegeneration are common during prion infection, but the mechanisms that underlie these pathological features are not well understood. Several components of innate immunity, such as Toll-like receptor (TLR) 4 and Complement C1q, have been shown to influence prion disease. To identify additional components of innate immunity that might impact prion disease within the central nervous system (CNS), we screened RNA from brains of pre-clinical and clinical 22L-infected mice for alterations in genes associated with innate immunity. Transcription of several genes encoding damage-associated molecular pattern (DAMP) proteins and receptors were increased in the brains of prion-infected mice. To investigate the role of some of these proteins in prion disease of the CNS, we infected mice deficient in DAMP receptor genes Tlr2, C3ar1, and C5ar1 with 22L scrapie. Elimination of TLR2 accelerated disease by a median of 10 days, while lack of C3aR1 or C5aR1 had no effect on disease tempo. Histopathologically, all knockout mouse strains tested were similar to infected control mice in gliosis, vacuolation, and PrPSc deposition. Analysis of proinflammatory markers in the brains of infected knockout mice indicated only a few alterations in gene expression suggesting that C5aR1 and TLR2 signaling did not act synergistically in the brains of prion-infected mice. These results indicate that signaling through TLR2 confers partial neuroprotection during prion infection.
Collapse
Affiliation(s)
- James A. Carroll
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, United States of America
| | - Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, United States of America
| | - Katie Williams
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, United States of America
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, United States of America
| |
Collapse
|
11
|
Bartoletti-Stella A, Corrado P, Mometto N, Baiardi S, Durrenberger PF, Arzberger T, Reynolds R, Kretzschmar H, Capellari S, Parchi P. Analysis of RNA Expression Profiles Identifies Dysregulated Vesicle Trafficking Pathways in Creutzfeldt-Jakob Disease. Mol Neurobiol 2018; 56:5009-5024. [PMID: 30446946 DOI: 10.1007/s12035-018-1421-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 11/01/2018] [Indexed: 12/21/2022]
Abstract
Functional genomics applied to the study of RNA expression profiles identified several abnormal molecular processes in experimental prion disease. However, only a few similar studies have been carried out to date in a naturally occurring human prion disease. To better characterize the transcriptional cascades associated with sporadic Creutzfeldt-Jakob disease (sCJD), the most common human prion disease, we investigated the global gene expression profile in samples from the frontal cortex of 10 patients with sCJD and 10 non-neurological controls by microarray analysis. The comparison identified 333 highly differentially expressed genes (hDEGs) in sCJD. Functional enrichment Gene Ontology analysis revealed that hDEGs were mainly associated with synaptic transmission, including GABA (q value = 0.049) and glutamate (q value = 0.005) signaling, and the immune/inflammatory response. Furthermore, the analysis of cellular components performed on hDEGs showed a compromised regulation of vesicle-mediated transport with mainly up-regulated genes related to the endosome (q value = 0.01), lysosome (q value = 0.04), and extracellular exosome (q value < 0.01). A targeted analysis of the retromer core component VPS35 (vacuolar protein sorting-associated protein 35) showed a down-regulation of gene expression (p value= 0.006) and reduced brain protein levels (p value= 0.002). Taken together, these results confirm and expand previous microarray expression profile data in sCJD. Most significantly, they also demonstrate the involvement of the endosomal-lysosomal system. Since the latter is a common pathogenic pathway linking together diseases, such as Alzheimer's and Parkinson's, it might be the focus of future studies aimed to identify new therapeutic targets in neurodegenerative diseases.
Collapse
Affiliation(s)
- Anna Bartoletti-Stella
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, 40139, Bologna, Italy
| | - Patrizia Corrado
- Department of Biomedical and NeuroMotor Sciences, DIBINEM, University of Bologna, 40123, Bologna, Italy
| | - Nicola Mometto
- Department of Biomedical and NeuroMotor Sciences, DIBINEM, University of Bologna, 40123, Bologna, Italy
| | - Simone Baiardi
- Department of Biomedical and NeuroMotor Sciences, DIBINEM, University of Bologna, 40123, Bologna, Italy
| | - Pascal F Durrenberger
- Centre for Inflammation and Tissue Repair, UCL Respiratory, University College London, Rayne Building, London, UK
| | - Thomas Arzberger
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians-University Munich, Munich, Germany.,Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich, Germany
| | | | - Hans Kretzschmar
- Center for Neuropathology and Prion Research, Ludwig-Maximilians-University Munich, Munich, Germany
| | - Sabina Capellari
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, 40139, Bologna, Italy. .,Department of Biomedical and NeuroMotor Sciences, DIBINEM, University of Bologna, 40123, Bologna, Italy.
| | - Piero Parchi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Ospedale Bellaria, 40139, Bologna, Italy. .,Department of Experimental, Diagnostic and Specialty Medicine, DIMES, University of Bologna, 40138, Bologna, Italy.
| |
Collapse
|
12
|
Microglia Are Critical in Host Defense against Prion Disease. J Virol 2018; 92:JVI.00549-18. [PMID: 29769333 DOI: 10.1128/jvi.00549-18] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 05/07/2018] [Indexed: 12/21/2022] Open
Abstract
Microglial cells in the central nervous system play important roles in neurodevelopment and resistance to infection, yet microglia can become neurotoxic under some conditions. An early event during prion infection is the activation of microglia and astrocytes in the brain prior to damage or death of neurons. Previous prion disease studies using two different strategies to manipulate signaling through the microglial receptor CSF-1R reported contrary effects on survival from prion disease. However, in these studies, reductions of microglial numbers and function were variable, thus confounding interpretation of the results. In the present work, we used oral treatment with a potent inhibitor of CSF-1R, PLX5622, to eliminate 78 to 90% of microglia from cortex early during the course of prion infection. Oral drug treatment early after infection with the RML scrapie strain significantly accelerated vacuolation, astrogliosis, and deposition of disease-associated prion protein. Furthermore, drug-treated mice had advanced clinical disease requiring euthanasia 31 days earlier than untreated control mice. Similarly, PLX5622 treatment during the preclinical phase at 80 days postinfection with RML scrapie also accelerated disease and resulted in euthanasia of mice 33 days earlier than infected controls. PLX5622 also accelerated clinical disease after infection with scrapie strains ME7 and 22L. Thus, microglia are critical in host defense during prion disease. The early accumulation of PrPSc in the absence of microglia suggested that microglia may function by clearing PrPSc, resulting in longer survival.IMPORTANCE Microglia contribute to many aspects of health and disease. When activated, microglia can be beneficial by repairing damage in the central nervous system (CNS) or they can turn harmful by becoming neurotoxic. In prion and prionlike diseases, the involvement of microglia in disease is unclear. Previous studies suggest that microglia can either speed up or slow down disease. In this study, we infected mice with prions and depleted microglia from the brains of mice using PLX5622, an effective CSF-1R tyrosine kinase inhibitor. Microglia were markedly reduced in brains, and prion disease was accelerated, so that mice needed to be euthanized 20 to 33 days earlier than infected control mice due to advanced clinical disease. Similar results occurred when mice were treated with PLX5622 at 80 days after infection, which was just prior to the start of clinical signs. Thus, microglia are important for removing prions, and the disease is faster when microglia are depleted.
Collapse
|
13
|
Vanni S, Zattoni M, Moda F, Giaccone G, Tagliavini F, Haïk S, Deslys JP, Zanusso G, Ironside JW, Carmona M, Ferrer I, Kovacs GG, Legname G. Hemoglobin mRNA Changes in the Frontal Cortex of Patients with Neurodegenerative Diseases. Front Neurosci 2018; 12:8. [PMID: 29403351 PMCID: PMC5786544 DOI: 10.3389/fnins.2018.00008] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 01/05/2018] [Indexed: 01/06/2023] Open
Abstract
Background: Hemoglobin is the major protein found in erythrocytes, where it acts as an oxygen carrier molecule. In recent years, its expression has been reported also in neurons and glial cells, although its role in brain tissue remains still unknown. Altered hemoglobin expression has been associated with various neurodegenerative disorders. Here, we investigated hemoglobin mRNA levels in brains of patients affected by variant, iatrogenic, and sporadic forms of Creutzfeldt-Jakob disease (vCJD, iCJD, sCJD, respectively) and in different genetic forms of prion diseases (gPrD) in comparison to Alzheimer's disease (AD) subjects and age-matched controls. Methods: Total RNA was obtained from the frontal cortex of vCJD (n = 20), iCJD (n = 11), sCJD (n = 23), gPrD (n = 30), and AD (n = 14) patients and age-matched controls (n = 30). RT-qPCR was performed for hemoglobin transcripts HBB and HBA1/2 using four reference genes for normalization. In addition, expression analysis of the specific erythrocyte marker ALAS2 was performed in order to account for blood contamination of the tissue samples. Hba1/2 and Hbb protein expression was then investigated with immunofluorescence and confocal microscope analysis. Results: We observed a significant up-regulation of HBA1/2 in vCJD brains together with a significant down-regulation of HBB in iCJD. In addition, while in sporadic and genetic forms of prion disease hemoglobin transcripts did not shown any alterations, both chains display a strong down-regulation in AD brains. These results were confirmed also at a protein level. Conclusions: These data indicate distinct hemoglobin transcriptional responses depending on the specific alterations occurring in different neurodegenerative diseases. In particular, the initial site of misfolding event (central nervous system vs. peripheral tissue)-together with specific molecular and conformational features of the pathological agent of the disease-seem to dictate the peculiar hemoglobin dysregulation found in prion and non-prion neurodegenerative disorders. In addition, these results suggest that gene expression of HBB and HBA1/2 in brain tissue is differentially affected by distinct prion and prion-like aggregating protein strains. Validation of these results in more accessible tissues could prompt the development of novel diagnostic tests for neurodegenerative disorders.
Collapse
Affiliation(s)
- Silvia Vanni
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati, Trieste, Italy
| | - Marco Zattoni
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati, Trieste, Italy
| | - Fabio Moda
- Neurology and Neuropathology Unit, Istituto di Ricovero e Cura a Carattere Scientifico Foundation Carlo Besta Neurological Institute, Milan, Italy
| | - Giorgio Giaccone
- Neurology and Neuropathology Unit, Istituto di Ricovero e Cura a Carattere Scientifico Foundation Carlo Besta Neurological Institute, Milan, Italy
| | - Fabrizio Tagliavini
- Neurology and Neuropathology Unit, Istituto di Ricovero e Cura a Carattere Scientifico Foundation Carlo Besta Neurological Institute, Milan, Italy
| | - Stéphane Haïk
- UPMC Univ Paris 06 UMR S 1127 and Centre National de la Recherche Scientifique UMR 7225, ICM, Sorbonne Universités, Paris, France
| | | | - Gianluigi Zanusso
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - James W Ironside
- National CJD Research and Surveillance Unit, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Margarita Carmona
- Department of Pathology and Experimental Therapeutics, University of Barcelona, Barcelona, Spain
| | - Isidre Ferrer
- Institut d'Investigació Biomédica de Bellvitge (IDIBELL), Bellvitge University Hospital (CIBERNED), Hospitalet de LLobregat, Spain
| | - Gabor G Kovacs
- Institute of Neurology, Medical University of Vienna, Vienna, Austria
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati, Trieste, Italy
| |
Collapse
|
14
|
Abstract
Prion diseases are unique neurodegenerative pathologies that can occur with sporadic, genetic, and acquired etiologies. Human and animal prion diseases can be recapitulated in laboratory animals with good reproducibility providing highly controlled models for studying molecular mechanisms of neurodegeneration. In this chapter the overall area of omics research in prion diseases is described. The term omics includes all fields of studies that employ a comprehensive, unbiased, and high-throughput approach to areas of research such as functional genomics, transcriptomics, and proteomics. These kind of approaches can be extremely helpful in identifying disease susceptibility factors and pathways that are dysregulated upon the onset and the progression of the disease. Herein, the most important research about the various forms of prion pathologies in human and in models of prion diseases in animals is presented and discussed.
Collapse
|
15
|
Xerxa E, Barbisin M, Chieppa MN, Krmac H, Vallino Costassa E, Vatta P, Simmons M, Caramelli M, Casalone C, Corona C, Legname G. Whole Blood Gene Expression Profiling in Preclinical and Clinical Cattle Infected with Atypical Bovine Spongiform Encephalopathy. PLoS One 2016; 11:e0153425. [PMID: 27073865 PMCID: PMC4830546 DOI: 10.1371/journal.pone.0153425] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 03/29/2016] [Indexed: 12/12/2022] Open
Abstract
Prion diseases, such as bovine spongiform encephalopathies (BSE), are transmissible neurodegenerative disorders affecting humans and a wide variety of mammals. Variant Creutzfeldt-Jakob disease (vCJD), a prion disease in humans, has been linked to exposure to BSE prions. This classical BSE (cBSE) is now rapidly disappearing as a result of appropriate measures to control animal feeding. Besides cBSE, two atypical forms (named H- and L-type BSE) have recently been described in Europe, Japan, and North America. Here we describe the first wide-spectrum microarray analysis in whole blood of atypical BSE-infected cattle. Transcriptome changes in infected animals were analyzed prior to and after the onset of clinical signs. The microarray analysis revealed gene expression changes in blood prior to the appearance of the clinical signs and during the progression of the disease. A set of 32 differentially expressed genes was found to be in common between clinical and preclinical stages and showed a very similar expression pattern in the two phases. A 22-gene signature showed an oscillating pattern of expression, being differentially expressed in the preclinical stage and then going back to control levels in the symptomatic phase. One gene, SEL1L3, was downregulated during the progression of the disease. Most of the studies performed up to date utilized various tissues, which are not suitable for a rapid analysis of infected animals and patients. Our findings suggest the intriguing possibility to take advantage of whole blood RNA transcriptional profiling for the preclinical identification of prion infection. Further, this study highlighted several pathways, such as immune response and metabolism that may play an important role in peripheral prion pathogenesis. Finally, the gene expression changes identified in the present study may be further investigated as a fingerprint for monitoring the progression of disease and for developing targeted therapeutic interventions.
Collapse
Affiliation(s)
- Elena Xerxa
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Functional and Structural Genomics sector, Trieste, Italy
| | - Maura Barbisin
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Functional and Structural Genomics sector, Trieste, Italy
| | - Maria Novella Chieppa
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Torino, Italy
| | - Helena Krmac
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Functional and Structural Genomics sector, Trieste, Italy
| | - Elena Vallino Costassa
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Torino, Italy
| | - Paolo Vatta
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Functional and Structural Genomics sector, Trieste, Italy
| | - Marion Simmons
- Pathology Department, Animal and Plant Health Agency (Weybridge), New Haw, Addlestone, United Kingdom
| | - Maria Caramelli
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Torino, Italy
| | - Cristina Casalone
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Torino, Italy
| | - Cristiano Corona
- Istituto Zooprofilattico Sperimentale del Piemonte Liguria e Valle d'Aosta, Torino, Italy
| | - Giuseppe Legname
- Scuola Internazionale Superiore di Studi Avanzati (SISSA), Functional and Structural Genomics sector, Trieste, Italy
- * E-mail:
| |
Collapse
|
16
|
Carroll JA, Striebel JF, Rangel A, Woods T, Phillips K, Peterson KE, Race B, Chesebro B. Prion Strain Differences in Accumulation of PrPSc on Neurons and Glia Are Associated with Similar Expression Profiles of Neuroinflammatory Genes: Comparison of Three Prion Strains. PLoS Pathog 2016; 12:e1005551. [PMID: 27046083 PMCID: PMC4821575 DOI: 10.1371/journal.ppat.1005551] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/14/2016] [Indexed: 12/31/2022] Open
Abstract
Misfolding and aggregation of host proteins are important features of the pathogenesis of neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease, frontotemporal dementia and prion diseases. In all these diseases, the misfolded protein increases in amount by a mechanism involving seeded polymerization. In prion diseases, host prion protein is misfolded to form a pathogenic protease-resistant form, PrPSc, which accumulates in neurons, astroglia and microglia in the CNS. Here using dual-staining immunohistochemistry, we compared the cell specificity of PrPSc accumulation at early preclinical times post-infection using three mouse scrapie strains that differ in brain regional pathology. PrPSc from each strain had a different pattern of cell specificity. Strain 22L was mainly associated with astroglia, whereas strain ME7 was mainly associated with neurons and neuropil. In thalamus and cortex, strain RML was similar to 22L, but in substantia nigra, RML was similar to ME7. Expression of 90 genes involved in neuroinflammation was studied quantitatively using mRNA from thalamus at preclinical times. Surprisingly, despite the cellular differences in PrPSc accumulation, the pattern of upregulated genes was similar for all three strains, and the small differences observed correlated with variations in the early disease tempo. Gene upregulation correlated with activation of both astroglia and microglia detected in early disease prior to vacuolar pathology or clinical signs. Interestingly, the profile of upregulated genes in scrapie differed markedly from that seen in two acute viral CNS diseases (LaCrosse virus and BE polytropic Friend retrovirus) that had reactive gliosis at levels similar to our prion-infected mice. Accumulation of aggregates of misfolded protein in brain is a common feature of the damage seen in several neurodegenerative diseases including prion disease, Alzheimer’s disease and Parkinson’s disease. In the present work three strains of prion disease differed in accumulation of the disease-associated prion protein (PrPSc) on neurons and astroglial cells. These patterns were first detectable in the thalamus at 40–60 days after inoculation. This coincided with initial detection of gliosis and PrPSc deposition, but was far in advance of clinical signs or spongiform pathology. In spite of the different patterns of cellular PrPSc deposition, these three strains had similar patterns of expression of a large number of genes known to be active during neuroinflammatory responses and gliosis. However, the gene upregulation in scrapie differed markedly from that seen in two neurovirulent viral diseases, which also had abundant glial responses similar to those observed with prion infection.
Collapse
Affiliation(s)
- James A. Carroll
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - James F. Striebel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Alejandra Rangel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Tyson Woods
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Katie Phillips
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Karin E. Peterson
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail:
| |
Collapse
|
17
|
Newaz K, Sriram K, Bera D. Identification of Major Signaling Pathways in Prion Disease Progression Using Network Analysis. PLoS One 2015; 10:e0144389. [PMID: 26646948 PMCID: PMC4672924 DOI: 10.1371/journal.pone.0144389] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 11/17/2015] [Indexed: 12/27/2022] Open
Abstract
Prion diseases are transmissible neurodegenerative diseases that arise due to conformational change of normal, cellular prion protein (PrPC) to protease-resistant isofrom (rPrPSc). Deposition of misfolded PrpSc proteins leads to an alteration of many signaling pathways that includes immunological and apoptotic pathways. As a result, this culminates in the dysfunction and death of neuronal cells. Earlier works on transcriptomic studies have revealed some affected pathways, but it is not clear which is (are) the prime network pathway(s) that change during the disease progression and how these pathways are involved in crosstalks with each other from the time of incubation to clinical death. We perform network analysis on large-scale transcriptomic data of differentially expressed genes obtained from whole brain in six different mouse strain-prion strain combination models to determine the pathways involved in prion diseases, and to understand the role of crosstalks in disease propagation. We employ a notion of differential network centrality measures on protein interaction networks to identify the potential biological pathways involved. We also propose a crosstalk ranking method based on dynamic protein interaction networks to identify the core network elements involved in crosstalk with different pathways. We identify 148 DEGs (differentially expressed genes) potentially related to the prion disease progression. Functional association of the identified genes implicates a strong involvement of immunological pathways. We extract a bow-tie structure that is potentially dysregulated in prion disease. We also propose an ODE model for the bow-tie network. Predictions related to diseased condition suggests the downregulation of the core signaling elements (PI3Ks and AKTs) of the bow-tie network. In this work, we show using transcriptomic data that the neuronal dysfunction in prion disease is strongly related to the immunological pathways. We conclude that these immunological pathways occupy influential positions in the PFNs (protein functional networks) that are related to prion disease. Importantly, this functional network involvement is prevalent in all the five different mouse strain-prion strain combinations that we studied. We also conclude that the dysregulation of the core elements of the bow-tie structure, which belongs to PI3K-Akt signaling pathway, leads to dysregulation of the downstream components corresponding to other biological pathways.
Collapse
Affiliation(s)
- Khalique Newaz
- Department of Computer Science, IIIT Delhi, New Delhi, India
| | - K. Sriram
- Center for Computational Biology, IIIT Delhi, New Delhi, India
| | - Debajyoti Bera
- Department of Computer Science, IIIT Delhi, New Delhi, India
| |
Collapse
|
18
|
Abstract
Background Prions diseases are fatal neurodegenerative diseases of mammals. While the molecular responses to prion infection have been extensively characterized in the laboratory mouse, little is known in other rodents. To explore these responses and make comparisons, we generated a prion disease in the laboratory rat by successive passage beginning with mouse RML prions. Results We describe the accumulation of rat prions, associated pathology and the transcriptional impact throughout the disease course. Comparative transcriptional profiling between laboratory mice and rats suggests that similar molecular and cellular processes are unfolding in response to prion infection. At the level of individual transcripts, however, variability exists between mice and rats and many genes deregulated by prion infection in mice are not affected in rats. Conclusion Our findings detail the molecular responses to prion disease in the rat and highlight the usefulness of comparative approaches to understanding neurodegeneration and prion diseases in particular. Electronic supplementary material The online version of this article (doi:10.1186/s12864-015-1884-7) contains supplementary material, which is available to authorized users.
Collapse
|
19
|
Majer A, Booth SA. Microdissection and transcriptional profiling: a window into the pathobiology of preclinical prion disease. Prion 2015; 8:67-74. [PMID: 24406429 DOI: 10.4161/pri.27729] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Prion diseases share common features on a sub-cellular level with many neurodegenerative diseases including Alzheimer disease; the most prevalent neurodegenerative disease world-wide. The most obvious similarity is the accumulation of misfolded forms of the host proteins which forms aggregates in the brains of patients. Remarkably, one of the earliest pathological changes detected in degenerating brain tissue, well before clinical symptoms are observed, is synaptic dysfunction and loss. This pathology was recently shown to be reversible in early stages of mouse prion disease suggesting that synaptic regeneration and reestablishment of neuronal function is possible. Determination of the molecular events that underlie synapse degeneration and how this eventually results in neuronal loss is therefore a research priority that may contribute to the search for new therapeutic interventions for neurodegenerative disorders. Functional genomic studies using unbiased whole genome expression analyses represent one method that can provide insights into these perplexing processes. However, transcriptional profiles from brain tissues are representative of a heterogeneous mixture of cell types that effectively mask the expression of low abundance transcripts, or molecular changes that occur only in a small population of affected neurons. One method that was recently applied to address these challenges was laser capture microdissection which was used to effectively isolate the CA1 neuronal rich region of the hippocampus prior to RNA extraction. Profiling of both mRNAs and microRNAs revealed previously unidentified neuronal-specific genes and expression signatures that are relevant to understanding the pathophysiological processes involved in preclinical stages of prion disease. In this review we will highlight these molecular signatures and discuss their implications with respect to prion-induced neurodegeneration.
Collapse
|
20
|
Prion infection of mouse brain reveals multiple new upregulated genes involved in neuroinflammation or signal transduction. J Virol 2014; 89:2388-404. [PMID: 25505076 DOI: 10.1128/jvi.02952-14] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
UNLABELLED Gliosis is often a preclinical pathological finding in neurodegenerative diseases, including prion diseases, but the mechanisms facilitating gliosis and neuronal damage in these diseases are not understood. To expand our knowledge of the neuroinflammatory response in prion diseases, we assessed the expression of key genes and proteins involved in the inflammatory response and signal transduction in mouse brain at various times after scrapie infection. In brains of scrapie-infected mice at pre- and postclinical stages, we identified 15 previously unreported differentially expressed genes related to inflammation or activation of the STAT signal transduction pathway. Levels for the majority of differentially expressed genes increased with time postinfection. In quantitative immunoblotting experiments of STAT proteins, STAT1α, phosphorylated-STAT1α (pSTAT1α), and pSTAT3 were increased between 94 and 131 days postinfection (p.i.) in brains of mice infected with strain 22L. Furthermore, a select group of STAT-associated genes was increased preclinically during scrapie infection, suggesting early activation of the STAT signal transduction pathway. Comparison of inflammatory markers between mice infected with scrapie strains 22L and RML indicated that the inflammatory responses and gene expression profiles in the brains were strikingly similar, even though these scrapie strains infect different brain regions. The endogenous interleukin-1 receptor antagonist (IL-1Ra), an inflammatory marker, was newly identified as increasing preclinically in our model and therefore might influence scrapie pathogenesis in vivo. However, in IL-1Ra-deficient or overexpressor transgenic mice inoculated with scrapie, neither loss nor overexpression of IL-1Ra demonstrated any observable effect on gliosis, protease-resistant prion protein (PrPres) formation, disease tempo, pathology, or expression of the inflammatory genes analyzed. IMPORTANCE Prion infection leads to PrPres deposition, gliosis, and neuroinflammation in the central nervous system before signs of clinical illness. Using a scrapie mouse model of prion disease to assess various time points postinoculation, we identified 15 unreported genes that were increased in the brains of scrapie-infected mice and were associated with inflammation and/or JAK-STAT activation. Comparison of mice infected with two scrapie strains (22L and RML), which have dissimilar neuropathologies, indicated that the inflammatory responses and gene expression profiles in the brains were similar. Genes that increased prior to clinical signs might be involved in controlling scrapie infection or in facilitating damage to host tissues. We tested the possible role of the endogenous IL-1Ra, which was increased at 70 days p.i. In scrapie-infected mice deficient in or overexpressing IL-1Ra, there was no observable effect on gliosis, PrPres formation, disease tempo, pathology, or expression of inflammatory genes analyzed.
Collapse
|
21
|
Shott RH, Appanah C, Grenier C, Tremblay G, Roucou X, Schang LM. Development of kinomic analyses to identify dysregulated signaling pathways in cells expressing cytoplasmic PrP. Virol J 2014; 11:175. [PMID: 25280966 PMCID: PMC4283144 DOI: 10.1186/1743-422x-11-175] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 09/26/2014] [Indexed: 12/20/2022] Open
Abstract
Background Dysregulated protein kinase signaling is involved in the pathogenesis of many chronic diseases. However, the dysregulated signaling pathways critical to prion pathogenesis remain incompletely characterized. Global analyses of signaling pathways may be useful to better characterize these pathways. We therefore set out to develop such global assays. To this end, we used as a model cytoplasmic mutants of the cellular prion protein (PrPC), which are toxic to N2a neuroblastoma cells. We tested the global assays for their sensitivity to detect changes in signaling pathways in cells expressing cytoplasmic PrP mutants. Methods We developed a targeted proteomics (kinomics) approach using multiplex Western blots to identify signaling pathways dysregulated in chronic neurological pathologies. We tested the approach for its potential ability to detect signaling changes in N2a cells expressing cytoplasmic PrP mutants. Results Multiplex Western blots were designed to quantitate the expression levels of 137 protein kinases in a single membrane and using only 1.2 mg of sample. The response of the blots was sensitive and linear to changes of 6% in protein levels. Hierarchical and functional clustering of the relative expression levels identified an mTOR signaling pathway as potentially dysregulated in N2a cells expressing cytoplasmic PrP. The mTOR signaling pathway regulates global protein synthesis, which is inhibited in cells expressing cytoplasmic PrP. The levels of proteins involved in the Akt1/p70S6K branch of mTOR signaling changed in synchrony with time of cytoplasmic PrP expression. Three kinases in this pathway, Akt, p70S6K, and eIF4B were in their inactive states, as evaluated by phosphorylation of their regulatory sites. Conclusion The results presented are consistent with the previously reported inhibition of Akt/p70S6K/eIF4B signaling as mediating pathogenesis of cytoplasmic PrP. We conclude that the kinomic analyses are sensitive and specific to detect signaling pathways dysregulated in a simple in vitro model of PrP pathogenesis. Electronic supplementary material The online version of this article (doi:10.1186/1743-422X-11-175) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | | | | | | | | | - Luis M Schang
- Department of Biochemistry and Centre for Prions and Protein Folding Diseases (CPPFD), University of Alberta, Edmonton, AB T6G 2E1, Canada.
| |
Collapse
|
22
|
Shott RH, Majer A, Frost KL, Booth SA, Schang LM. Activation of pro-survival CaMK4β/CREB and pro-death MST1 signaling at early and late times during a mouse model of prion disease. Virol J 2014; 11:160. [PMID: 25183307 PMCID: PMC4168054 DOI: 10.1186/1743-422x-11-160] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 08/29/2014] [Indexed: 12/17/2022] Open
Abstract
Background The signaling pathways most critical to prion disease pathogenesis are as yet incompletely characterized. We have developed a kinomics approach to identify signaling pathways that are dysregulated during prion pathogenesis. The approach is sensitive and specific enough to detect signaling pathways dysregulated in a simple in vitro model of prion pathogenesis. Here, we used this approach to identify signaling pathways dysregulated during prion pathogenesis in vivo. Methods Mice intraperitoneally infected with scrapie (strain RML) were euthanized at 70, 90, 110, 130 days post-infection (dpi) or at terminal stages of disease (155–190 dpi). The levels of 139 protein kinases in brainstem-cerebellum homogenates were analyzed by multiplex Western blots, followed by hierarchical clustering and analyses of activation states. Results Hierarchical and functional clustering identified CaMK4β and MST1 signaling pathways as potentially dysregulated. Targeted analyses revealed that CaMK4β and its downstream substrate CREB, which promotes neuronal survival, were activated at 70 and 90 dpi in cortical, subcortical and brainstem-cerebellum homogenates from scrapie-infected mice. The activation levels of CaMK4β/CREB signaling returned to those in mock-infected mice at 110 dpi, whereas MST1, which promotes neuronal death, became activated at 130 dpi. Conclusion Pro-survival CaMK4β/CREB signaling is activated in mouse scrapie at earlier times and later inhibited, whereas pro-death MST1 signaling is activated at these later times. Electronic supplementary material The online version of this article (doi:10.1186/1743-422X-11-160) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
| | | | | | | | - Luis M Schang
- Department of Biochemistry and Centre for Prions and Protein Folding Diseases (CPPFD), University of Alberta, Edmonton, AB, Canada.
| |
Collapse
|
23
|
Moore RA, Sturdevant DE, Chesebro B, Priola SA. Proteomics analysis of amyloid and nonamyloid prion disease phenotypes reveals both common and divergent mechanisms of neuropathogenesis. J Proteome Res 2014; 13:4620-34. [PMID: 25140793 PMCID: PMC4227561 DOI: 10.1021/pr500329w] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
![]()
Prion
diseases are a heterogeneous group of neurodegenerative disorders
affecting various mammals including humans. Prion diseases are characterized
by a misfolding of the host-encoded prion protein (PrPC) into a pathological isoform termed PrPSc. In wild-type
mice, PrPC is attached to the plasma membrane by a glycosylphosphatidylinositol
(GPI) anchor and PrPSc typically accumulates in diffuse
nonamyloid deposits with gray matter spongiosis. By contrast, when
mice lacking the GPI anchor are infected with the same prion inoculum,
PrPSc accumulates in dense perivascular amyloid plaques
with little or no gray matter spongiosis. In order to evaluate whether
different host biochemical pathways were implicated in these two phenotypically
distinct prion disease models, we utilized a proteomics approach.
In both models, infected mice displayed evidence of a neuroinflammatory
response and complement activation. Proteins involved in cell death
and calcium homeostasis were also identified in both phenotypes. However,
mitochondrial pathways of apoptosis were implicated only in the nonamyloid
form, whereas metal binding and synaptic vesicle transport were more
disrupted in the amyloid phenotype. Thus, following infection with
a single prion strain, PrPC anchoring to the plasma membrane
correlated not only with the type of PrPSc deposition but
also with unique biochemical pathways associated with pathogenesis.
Collapse
Affiliation(s)
- Roger A Moore
- Laboratory of Persistent Viral Diseases and ‡Research Technologies Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases , Hamilton, Montana 59840, United States
| | | | | | | |
Collapse
|
24
|
Barbisin M, Vanni S, Schmädicke AC, Montag J, Motzkus D, Opitz L, Salinas-Riester G, Legname G. Gene expression profiling of brains from bovine spongiform encephalopathy (BSE)-infected cynomolgus macaques. BMC Genomics 2014; 15:434. [PMID: 24898206 PMCID: PMC4061447 DOI: 10.1186/1471-2164-15-434] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 05/07/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Prion diseases are fatal neurodegenerative disorders whose pathogenesis mechanisms are not fully understood. In this context, the analysis of gene expression alterations occurring in prion-infected animals represents a powerful tool that may contribute to unravel the molecular basis of prion diseases and therefore discover novel potential targets for diagnosis and therapeutics. Here we present the first large-scale transcriptional profiling of brains from BSE-infected cynomolgus macaques, which are an excellent model for human prion disorders. RESULTS The study was conducted using the GeneChip® Rhesus Macaque Genome Array and revealed 300 transcripts with expression changes greater than twofold. Among these, the bioinformatics analysis identified 86 genes with known functions, most of which are involved in cellular development, cell death and survival, lipid homeostasis, and acute phase response signaling. RT-qPCR was performed on selected gene transcripts in order to validate the differential expression in infected animals versus controls. The results obtained with the microarray technology were confirmed and a gene signature was identified. In brief, HBB and HBA2 were down-regulated in infected macaques, whereas TTR, APOC1 and SERPINA3 were up-regulated. CONCLUSIONS Some genes involved in oxygen or lipid transport and in innate immunity were found to be dysregulated in prion infected macaques. These genes are known to be involved in other neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. Our results may facilitate the identification of potential disease biomarkers for many neurodegenerative diseases.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Giuseppe Legname
- Department of Neuroscience, Scuola Internazionale Superiore di Studi Avanzati (SISSA), Via Bonomea 265, 34136 Trieste, Italy.
| |
Collapse
|
25
|
Filali H, Martín-Burriel I, Harders F, Varona L, Hedman C, Mediano DR, Monzón M, Bossers A, Badiola JJ, Bolea R. Gene expression profiling of mesenteric lymph nodes from sheep with natural scrapie. BMC Genomics 2014; 15:59. [PMID: 24450868 PMCID: PMC3906094 DOI: 10.1186/1471-2164-15-59] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2013] [Accepted: 01/17/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Prion diseases are characterized by the accumulation of the pathogenic PrPSc protein, mainly in the brain and the lymphoreticular system. Although prions multiply/accumulate in the lymph nodes without any detectable pathology, transcriptional changes in this tissue may reflect biological processes that contribute to the molecular pathogenesis of prion diseases. Little is known about the molecular processes that occur in the lymphoreticular system in early and late stages of prion disease. We performed a microarray-based study to identify genes that are differentially expressed at different disease stages in the mesenteric lymph node of sheep naturally infected with scrapie. Oligo DNA microarrays were used to identify gene-expression profiles in the early/middle (preclinical) and late (clinical) stages of the disease. RESULTS In the clinical stage of the disease, we detected 105 genes that were differentially expressed (≥2-fold change in expression). Of these, 43 were upregulated and 62 downregulated as compared with age-matched negative controls. Fewer genes (50) were differentially expressed in the preclinical stage of the disease. Gene Ontology enrichment analysis revealed that the differentially expressed genes were largely associated with the following terms: glycoprotein, extracellular region, disulfide bond, cell cycle and extracellular matrix. Moreover, some of the annotated genes could be grouped into 3 specific signaling pathways: focal adhesion, PPAR signaling and ECM-receptor interaction. We discuss the relationship between the observed gene expression profiles and PrPSc deposition and the potential involvement in the pathogenesis of scrapie of 7 specific differentially expressed genes whose expression levels were confirmed by real time-PCR. CONCLUSIONS The present findings identify new genes that may be involved in the pathogenesis of natural scrapie infection in the lymphoreticular system, and confirm previous reports describing scrapie-induced alterations in the expression of genes involved in protein misfolding, angiogenesis and the oxidative stress response. Further studies will be necessary to determine the role of these genes in prion replication, dissemination and in the response of the organism to this disease.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | | | - Rosa Bolea
- Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain.
| |
Collapse
|
26
|
Cho IS, Spinner DS, Kascsak RJ, Meeker HC, Kim BS, Park SY, Schuller-Levis G, Park E. Altered lymphocyte proliferation and innate immune function in scrapie 139A- and ME7-infected mice. Viral Immunol 2013; 26:192-200. [PMID: 23656168 DOI: 10.1089/vim.2012.0091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Lymphoid organs play an important role in prion disease development and progression. While the role of lymphoid organs and changes in immune-related genes have been extensively investigated in scrapie-infected animals, innate immunity has not. Previous studies examined lymphocyte function in scrapie-infected C3H/HeJ mice, which exhibit defects in lipopolysaccharide (LPS) response now known to result from a mutation in Toll-like receptor (TLR) 4. We examined immune function in scrapie-infected CD1 mice, which are LPS responders. Lymphocyte proliferation from CD1 mice infected with either 139A or ME7 scrapie was measured in response to concanavalin (Con) A or LPS at 1 and 3 months after infection. Following LPS exposure, mice infected 3 months with ME7, but not 139A, demonstrated significantly decreased lymphocyte proliferation compared to controls. After Con A exposure, lymphocyte proliferation in scrapie-infected mice did not differ from controls. Gender-specific comparison of lymphocyte proliferation showed significant decreases in mitogenic responses in females infected 3 months with either 139A or ME7, compared to controls. Males infected for 3 months with ME7, but not 139A, showed significantly decreased proliferation after lymphocyte exposure to LPS, but not Con A. Neither gender showed changes in lymphocyte proliferation after 1 month of scrapie infection. Innate immune activation of peritoneal macrophages was determined via production of nitric oxide (NO), IL-6, and TNF-α after exposure to TLR ligands. TNF-α and IL-6 production were reduced in macrophages from females infected with either scrapie strain for 3 months, while NO production after TLR agonist plus IFN-γ exposure was decreased in both females and males infected for 3 months with 139A, compared to ME7. These data demonstrated altered innate immunity, suggesting hormonal and/or other gender-specific regulation may contribute to gender differences in some immune functions. Our data demonstrate lymphocyte proliferation and innate immune functioning in scrapie-infected mice deteriorate with disease progression.
Collapse
Affiliation(s)
- In Soo Cho
- Animal, Plant and Fisheries Quarantine and Inspection Agency, Anyang, Gyunggi-do, Republic of Korea
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Komolka K, Ponsuksili S, Schwerin M. Healthy sheep that differ in scrapie associated PRNP genotypes exhibit significant differences of expression pattern associated with immune response and cell-to-cell signalling in retropharyngeal lymph nodes. Vet Immunol Immunopathol 2013; 152:370-80. [PMID: 23428361 DOI: 10.1016/j.vetimm.2013.01.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 01/14/2013] [Accepted: 01/21/2013] [Indexed: 11/28/2022]
Abstract
The present study was conducted to test the hypothesis whether prion protein gene (PRNP) associated scrapie susceptibility is connected with physiological changes in tissue involved in pathogen uptake, migration and propagation. Jejunum, ileal Peyer's patches, retropharyngeal lymph nodes, brain stem and liver of healthy and non scrapie-infected sheep with PRNP genotypes representing the scrapie risk class R1 (scrapie-resistant) and R5 (scrapie-susceptible), respectively, were comparatively analysed by microarray technology and quantitative reverse transcriptase polymerase chain reaction (RT qPCR). Significantly higher expression levels of genes involved in immune response and cell communication pathways in retropharyngeal lymph nodes of R1 sheep in comparison with R5 animals strongly suggest PRNP associated physiological processes with impact as an early barrier in pathogen defence. Equal expression patterns in brain stem suggest no physiological differences in brain of healthy R1 and R5 animals. In addition, similar expression pattern in liver indicates that there are no transcriptional differences in genes of the hepatic energy metabolism between animals of scrapie classes R1 and R5.
Collapse
Affiliation(s)
- Katrin Komolka
- Research Group Functional Genomics, Leibniz Institute for Farm Animal Biology, Dummerstorf, Germany
| | | | | |
Collapse
|
28
|
Filali H, Vidal E, Bolea R, Márquez M, Marco P, Vargas A, Pumarola M, Martin-Burriel I, Badiola JJ. Gene and protein patterns of potential prion-related markers in the central nervous system of clinical and preclinical infected sheep. Vet Res 2013; 44:14. [PMID: 23497022 PMCID: PMC3608070 DOI: 10.1186/1297-9716-44-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 02/05/2013] [Indexed: 12/15/2022] Open
Abstract
The molecular pathogenic mechanisms of prion diseases are far from clear. Genomic analyses have revealed genetic biomarkers potentially involved in prion neuropathology in naturally scrapie-infected sheep, a good animal model of infectious prionopathies. However, these biomarkers must be validated in independent studies at different stages of the disease. The gene and protein expression profiles and protein distribution of six potential genetic biomarkers (i.e., CAPN6, COL1A2, COL3A1, GALA1, MT2A and MTNR1B) are presented here for both the early and terminal stages of scrapie in five different brain regions. Gene transcription changes were confirmed in the medulla oblongata, and the expression profiles were generally similar in other central nervous system regions. The changes were more substantial in clinical animals compared to preclinical animals. The expression of the CAPN6 protein increased in the spinal cord and cerebellum of the clinical and preclinical brains. The distribution of the GALA1 was identified in glial cells from the cerebellum of scrapie-infected animals, GALA1 protein expression was increased in clinical animals in the majority of regions, and the increase of MT2A was in agreement with previous reports. The downregulation of MTNR1B was especially marked in the Purkinje cells. Finally, although collagen genes were downregulated the protein immunostaining did not reveal significant changes between the scrapie-infected and control animals. In conclusion, this study of gene transcription and protein expression and distribution confirm CAPN6, GALA1, MTNR1B and MT2A as potential targets for further prion disease research.
Collapse
Affiliation(s)
- Hicham Filali
- Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain.
| | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Basu U, Guan LL, Moore SS. Functional genomics approach for identification of molecular processes underlying neurodegenerative disorders in prion diseases. Curr Genomics 2013; 13:369-78. [PMID: 23372423 PMCID: PMC3401894 DOI: 10.2174/138920212801619223] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Revised: 05/30/2012] [Accepted: 05/30/2012] [Indexed: 12/11/2022] Open
Abstract
Prion diseases or transmissible spongiform encephalopathies (TSEs) are infectious neurodegenerative disorders leading to death. These include Cresutzfeldt-Jakob disease (CJD), familial, sporadic and variant CJD and kuru in humans; and animal TSEs include scrapie in sheep, bovine spongiform encephalopathy (BSE) in cattle, chronic wasting disease (CWD) of mule deer and elk, and transmissible mink encephalopathy. All these TSEs share common pathological features such as accumulation of mis-folded prion proteins in the central nervous system leading to cellular dysfunction and cell death. It is important to characterize the molecular pathways and events leading to prion induced neurodegeneration. Here we discuss the impact of the functional genomics approaches including microarrays, subtractive hybridization and microRNA profiling in elucidating transcriptional cascades at different stages of disease. Many of these transcriptional changes have been observed in multiple neurodegenerative diseases which may aid in identification of biomarkers for disease. A comprehensive characterization of expression profiles implicated in neurodegenerative disorders will undoubtedly advance our understanding on neuropathology and dysfunction during prion disease and other neurodegenerative disorders. We also present an outlook on the future work which may focus on analysis of structural genetic variation, genome and transcriptome sequencing using next generation sequencing with an integrated approach on animal and human TSE related studies.
Collapse
Affiliation(s)
- Urmila Basu
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada T6G 2P5
| | | | | |
Collapse
|
30
|
Bradford BM, Mabbott NA. Prion disease and the innate immune system. Viruses 2012; 4:3389-419. [PMID: 23342365 PMCID: PMC3528271 DOI: 10.3390/v4123389] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2012] [Revised: 11/14/2012] [Accepted: 11/22/2012] [Indexed: 02/06/2023] Open
Abstract
Prion diseases or transmissible spongiform encephalopathies are a unique category of infectious protein-misfolding neurodegenerative disorders. Hypothesized to be caused by misfolding of the cellular prion protein these disorders possess an infectious quality that thrives in immune-competent hosts. While much has been discovered about the routing and critical components involved in the peripheral pathogenesis of these agents there are still many aspects to be discovered. Research into this area has been extensive as it represents a major target for therapeutic intervention within this group of diseases. The main focus of pathological damage in these diseases occurs within the central nervous system. Cells of the innate immune system have been proven to be critical players in the initial pathogenesis of prion disease, and may have a role in the pathological progression of disease. Understanding how prions interact with the host innate immune system may provide us with natural pathways and mechanisms to combat these diseases prior to their neuroinvasive stage. We present here a review of the current knowledge regarding the role of the innate immune system in prion pathogenesis.
Collapse
Affiliation(s)
- Barry M Bradford
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG, UK.
| | | |
Collapse
|
31
|
Rubenstein R. Proteomic analysis of prion diseases: creating clarity or causing confusion? Electrophoresis 2012; 33:3631-43. [PMID: 23161058 DOI: 10.1002/elps.201200310] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Revised: 06/25/2012] [Accepted: 07/04/2012] [Indexed: 11/10/2022]
Abstract
Prion diseases, or transmissible spongiform encephalopathies, are progressive, fatal neurodegenerative diseases. There are both human and animal forms of the disease and all are associated with the conversion of a normal host-coded cellular prion protein (PrP(C) ) into an abnormal protease-resistant isoform (PrP(Sc) ). Although methodologies are sensitive and specific for postmortem disease diagnosis, the use of PrP(Sc) as a preclinical or general biomarker for surveillance is difficult, due to the fact that it is present in extremely small amounts in accessible tissues or body fluids such as blood, urine, saliva, and cerebrospinal fluid. Recently, amplification techniques have been developed, which have enabled increased sensitivity for PrP(Sc) detection. However, it has recently been reported that proteinase K sensitive, pathological isoforms of PrP may have a significant role in the pathogenesis of some prion diseases. Accordingly, the development of new diagnostic tests that do not rely on PrP(Sc) and proteinase K digestion is desirable. The search for biomarkers (other than PrP(Sc) ) as tools for diagnosis of prion diseases has a long history. Ideally biomarkers able to detect all transmissible spongiform encephalopathies, even at preclinical stages of infection are desirable but not yet possible due to the heterogeneity of the disease and lengthy disease progression. Recent advances in neuroproteomics have led to an overwhelming amount of information, which may offer insight on protein-protein interactions. While the amount of data obtained is impressive, the ability to relate it to the disease and validating its usefulness in diagnostic biomarker development remains a formidable challenge.
Collapse
Affiliation(s)
- Richard Rubenstein
- Department of Neurology, SUNY Downstate Medical Center, Brooklyn, NY 11203, USA.
| |
Collapse
|
32
|
Filali H, Martin-Burriel I, Harders F, Varona L, Serrano C, Acín C, Badiola JJ, Bossers A, Bolea R. Medulla oblongata transcriptome changes during presymptomatic natural scrapie and their association with prion-related lesions. BMC Genomics 2012; 13:399. [PMID: 22897917 PMCID: PMC3495657 DOI: 10.1186/1471-2164-13-399] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Accepted: 08/06/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The pathogenesis of natural scrapie and other prion diseases is still poorly understood. Determining the variations in the transcriptome in the early phases of the disease might clarify some of the molecular mechanisms of the prion-induced pathology and allow for the development of new biomarkers for diagnosis and therapy. This study is the first to focus on the identification of genes regulated during the preclinical phases of natural scrapie in the ovine medulla oblongata (MO) and the association of these genes with prion deposition, astrocytosis and spongiosis. RESULTS A custom microarray platform revealed that 86 significant probes had expression changes greater than 2-fold. From these probes, we identified 32 genes with known function; the highest number of regulated genes was included in the phosphoprotein-encoding group. Genes encoding extracellular marker proteins and those involved in the immune response and apoptosis were also differentially expressed. In addition, we investigated the relationship between the gene expression profiles and the appearance of the main scrapie-associated brain lesions. Quantitative Real-time PCR was used to validate the expression of some of the regulated genes, thus showing the reliability of the microarray hybridization technology. CONCLUSIONS Genes involved in protein and metal binding and oxidoreductase activity were associated with prion deposition. The expression of glial fibrillary acidic protein (GFAP) was associated with changes in the expression of genes encoding proteins with oxidoreductase and phosphatase activity, and the expression of spongiosis was related to genes encoding extracellular matrix components or transmembrane transporters. This is the first genome-wide expression study performed in naturally infected sheep with preclinical scrapie. As in previous studies, our findings confirm the close relationship between scrapie and other neurodegenerative diseases.
Collapse
Affiliation(s)
- Hicham Filali
- Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes, Facultad de Veterinaria, Universidad de Zaragoza, Zaragoza, Spain
| | | | | | | | | | | | | | | | | |
Collapse
|
33
|
Basu U, Almeida LM, Dudas S, Graham CE, Czub S, Moore SS, Guan LL. Gene expression alterations in Rocky Mountain elk infected with chronic wasting disease. Prion 2012; 6:282-301. [PMID: 22561165 DOI: 10.4161/pri.19915] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Chronic wasting disease (CWD) is an invariably fatal neurologic disease that naturally infects mule deer, white tailed deer and elk. The understanding of CWD neurodegeneration at a molecular level is very limited. In this study, microarray analysis was performed to determine changes in the gene expression profiles in six different tissues including brain, midbrain, thalamus, spleen, RPLN and tonsil of CWD-infected elk in comparison to non-infected healthy elk, using 24,000 bovine specific oligo probes. In total, 329 genes were found to be differentially expressed (> 2.0-fold) between CWD negative and positive brain tissues, with 132 genes upregulated and 197 genes downregulated. There were 249 DE genes in the spleen (168 up- and 81 downregulated), 30 DE genes in the retropharyngeal lymph node (RPLN) (18 up- and 12 downregulated), and 55 DE genes in the tonsil (21 up- and 34 downregulated). Using Gene Ontology (GO), the DE genes were assigned to functional groups associated with cellular process, biological regulation, metabolic process, and regulation of biological process. For all brain tissues, the highest ranking networks for DE genes identified by Ingenuity Pathway Analysis (IPA) were associated with neurological disease, cell morphology, cellular assembly and organization. Quantitative real-time PCR (qRT-PCR) validated the expression of DE genes primarily involved in different regulatory pathways, including neuronal signaling and synapse function, calcium signaling, apoptosis and cell death and immune cell trafficking and inflammatory response. This is the first study to evaluate altered gene expression in multiple organs including brain from orally infected elk and the results will improve our understanding of CWD neurodegeneration at the molecular level.
Collapse
Affiliation(s)
- Urmila Basu
- Department of Agricultural, Food & Nutritional Science, University of Alberta, Edmonton, AB, Canada
| | | | | | | | | | | | | |
Collapse
|
34
|
Vounou M, Janousova E, Wolz R, Stein JL, Thompson PM, Rueckert D, Montana G. Sparse reduced-rank regression detects genetic associations with voxel-wise longitudinal phenotypes in Alzheimer's disease. Neuroimage 2011; 60:700-16. [PMID: 22209813 DOI: 10.1016/j.neuroimage.2011.12.029] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 11/18/2011] [Accepted: 12/14/2011] [Indexed: 11/17/2022] Open
Abstract
Scanning the entire genome in search of variants related to imaging phenotypes holds great promise in elucidating the genetic etiology of neurodegenerative disorders. Here we discuss the application of a penalized multivariate model, sparse reduced-rank regression (sRRR), for the genome-wide detection of markers associated with voxel-wise longitudinal changes in the brain caused by Alzheimer's disease (AD). Using a sample from the Alzheimer's Disease Neuroimaging Initiative database, we performed three separate studies that each compared two groups of individuals to identify genes associated with disease development and progression. For each comparison we took a two-step approach: initially, using penalized linear discriminant analysis, we identified voxels that provide an imaging signature of the disease with high classification accuracy; then we used this multivariate biomarker as a phenotype in a genome-wide association study, carried out using sRRR. The genetic markers were ranked in order of importance of association to the phenotypes using a data re-sampling approach. Our findings confirmed the key role of the APOE and TOMM40 genes but also highlighted some novel potential associations with AD.
Collapse
Affiliation(s)
- Maria Vounou
- Statistics Section, Department of Mathematics, Imperial College London, UK
| | | | | | | | | | | | | |
Collapse
|
35
|
Avrahami D, Gabizon R. Age-related alterations affect the susceptibility of mice to prion infection. Neurobiol Aging 2011; 32:2006-15. [DOI: 10.1016/j.neurobiolaging.2009.12.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2009] [Revised: 12/10/2009] [Accepted: 12/21/2009] [Indexed: 12/29/2022]
|
36
|
Tortosa R, Castells X, Vidal E, Costa C, Ruiz de Villa MDC, Sánchez A, Barceló A, Torres JM, Pumarola M, Ariño J. Central nervous system gene expression changes in a transgenic mouse model for bovine spongiform encephalopathy. Vet Res 2011; 42:109. [PMID: 22035425 PMCID: PMC3225326 DOI: 10.1186/1297-9716-42-109] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 10/28/2011] [Indexed: 12/04/2022] Open
Abstract
Gene expression analysis has proven to be a very useful tool to gain knowledge of the factors involved in the pathogenesis of diseases, particularly in the initial or preclinical stages. With the aim of finding new data on the events occurring in the Central Nervous System in animals affected with Bovine Spongiform Encephalopathy, a comprehensive genome wide gene expression study was conducted at different time points of the disease on mice genetically modified to model the bovine species brain in terms of cellular prion protein. An accurate analysis of the information generated by microarray technique was the key point to assess the biological relevance of the data obtained in terms of Transmissible Spongiform Encephalopathy pathogenesis. Validation of the microarray technique was achieved by RT-PCR confirming the RNA change and immunohistochemistry techniques that verified that expression changes were translated into variable levels of protein for selected genes. Our study reveals changes in the expression of genes, some of them not previously associated with prion diseases, at early stages of the disease previous to the detection of the pathological prion protein, that might have a role in neuronal degeneration and several transcriptional changes showing an important imbalance in the Central Nervous System homeostasis in advanced stages of the disease. Genes whose expression is altered at early stages of the disease should be considered as possible therapeutic targets and potential disease markers in preclinical diagnostic tool development. Genes non-previously related to prion diseases should be taken into consideration for further investigations.
Collapse
Affiliation(s)
- Raül Tortosa
- Departament de Medicina i Cirurgia Animals, Universitat Autònoma de Barcelona, 08193, Cerdanyola del Vallès, Barcelona, Spain.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Gossner A, Roupaka S, Foster J, Hunter N, Hopkins J. Transcriptional profiling of peripheral lymphoid tissue reveals genes and networks linked to SSBP/1 scrapie pathology in sheep. Vet Microbiol 2011; 153:218-28. [PMID: 21684093 DOI: 10.1016/j.vetmic.2011.05.036] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Revised: 05/10/2011] [Accepted: 05/16/2011] [Indexed: 12/30/2022]
Abstract
Transmissible spongiform encephalopathies (TSEs) are slow and progressive neurodegenerative diseases of humans and animals. The major target organ for all TSEs is the brain but some TSE agents are associated with prior accumulation within the peripheral lymphoid system. Many studies have examined the effects of scrapie infection on the expression of central nervous system (CNS) genes, but this study examines the progression of scrapie pathology in the peripheral lymphoid system and how scrapie infection affects the transcriptome of the lymph nodes and spleen. Infection of sheep with SSBP/1 scrapie resulted in PrP(Sc) deposition in the draining prescapular lymph node (PSLN) by 25 days post infection (dpi) in VRQ/VRQ genotype sheep and 75 dpi in tonsils and spleen. Progression of PrP(Sc) deposition in VRQ/ARR animals was 25 dpi later in the PSLN and 250 dpi later in spleen. Microarray analysis of 75 dpi tissues from VRQ/VRQ sheep identified 52 genes in PSLN and 37 genes in spleen cells that showed significant difference (P ≤ 0.05) between scrapie-infected and mock-infected animals. Transcriptional pathway analysis highlighted immunological disease, cell death and neurological disease as the biological pathways associated with scrapie pathogenesis in the peripheral lymphoid system. PrP(Sc) accumulation of lymphoid tissue resulted in the repression of genes linked to inflammation and oxidative stress, and the up-regulation of genes related to apoptosis.
Collapse
Affiliation(s)
- Anton Gossner
- The Roslin Institute & R(D)SVS, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | | | | | | | | |
Collapse
|
38
|
Gene expression profiling and association with prion-related lesions in the medulla oblongata of symptomatic natural scrapie animals. PLoS One 2011; 6:e19909. [PMID: 21629698 PMCID: PMC3101219 DOI: 10.1371/journal.pone.0019909] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Accepted: 04/06/2011] [Indexed: 02/04/2023] Open
Abstract
The pathogenesis of natural scrapie and other prion diseases remains unclear. Examining transcriptome variations in infected versus control animals may highlight new genes potentially involved in some of the molecular mechanisms of prion-induced pathology. The aim of this work was to identify disease-associated alterations in the gene expression profiles of the caudal medulla oblongata (MO) in sheep presenting the symptomatic phase of natural scrapie. The gene expression patterns in the MO from 7 sheep that had been naturally infected with scrapie were compared with 6 controls using a Central Veterinary Institute (CVI) custom designed 4×44K microarray. The microarray consisted of a probe set on the previously sequenced ovine tissue library by CVI and was supplemented with all of the Ovis aries transcripts that are currently publicly available. Over 350 probe sets displayed greater than 2-fold changes in expression. We identified 148 genes from these probes, many of which encode proteins that are involved in the immune response, ion transport, cell adhesion, and transcription. Our results confirm previously published gene expression changes that were observed in murine models with induced scrapie. Moreover, we have identified new genes that exhibit differential expression in scrapie and could be involved in prion neuropathology. Finally, we have investigated the relationship between gene expression profiles and the appearance of the main scrapie-related lesions, including prion protein deposition, gliosis and spongiosis. In this context, the potential impacts of these gene expression changes in the MO on scrapie development are discussed.
Collapse
|
39
|
Almeida LM, Basu U, Khaniya B, Taniguchi M, Williams JL, Moore SS, Guan LL. Gene expression in the medulla following oral infection of cattle with bovine spongiform encephalopathy. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2011; 74:110-126. [PMID: 21218340 DOI: 10.1080/15287394.2011.529061] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The identification of variations in gene expression in response to bovine spongiform encephalopathy (BSE) may help to elucidate the mechanisms of neuropathology and prion replication and discover biomarkers for disease. In this study, genes that are differentially expressed in the caudal medulla tissues of animals infected with different doses of PrP(BSE) at 12 and 45 mo post infection were compared using array containing 24,000 oligonucleotide probes. Data analysis identified 966 differentially expressed (DE) genes between control and infected animals. Genes identified in at least two of four experiments (control versus 1-g infected animals at 12 and 45-mo; control versus 100-g infected animals at 12 and 45 mo) were considered to be the genes that may be associated with BSE disease. From the 176 DE genes associated with BSE, 84 had functions described in the Gene Ontology (GO) database. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis of 14 genes revealed that prion infection may cause dysfunction of several different networks, including extracellular matrix (ECM), cell adhesion, neuroactive ligand-receptor interaction, complement and coagulation cascades, MAPK signaling, neurodegenerative disorder, SNARE interactions in vesicular transport, and the transforming growth factor (TGF) beta signaling pathways. The identification of DE genes will contribute to a better understanding of the molecular mechanisms of neuropathology in bovine species. Additional studies on larger number of animals are in progress in our laboratory to investigate the roles of these DE genes in pathogenesis of BSE.
Collapse
Affiliation(s)
- Luciane M Almeida
- Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, Alberta, Canada
| | | | | | | | | | | | | |
Collapse
|
40
|
Moody LR, Herbst AJ, Aiken JM. Upregulation of interferon-gamma-induced genes during prion infection. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2011; 74:146-153. [PMID: 21218343 PMCID: PMC4621959 DOI: 10.1080/15287394.2011.529064] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Global gene expression analysis allows for the identification of transcripts that are differentially regulated during a disease state. Many groups, including our own, have identified hundreds of genes differentially regulated in response to prion infection. Eleven transcripts, upregulated in the brains of prion-infected animals, which were classified in the literature as stimulated by the cytokine interferon-gamma (IFN-γ), were identified. This is intriguing, as IFN-γ has recently been detected in the brains of prion-infected animals. Quantitation of several genes, categorized as IFN-γ inducible, by quantitative real-time polymerase chain reaction (qRT-PCR) confirms that these transcripts are upregulated. Future approaches for delineating the role of IFN-γ-induced transcripts and their function in prion infection are described.
Collapse
Affiliation(s)
- Laura R. Moody
- Cellular and Molecular Biology Graduate Program; Department of Comparative Biosciences; University of Wisconsin, Madison, Wisconsin, USA
| | - Allen J. Herbst
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
| | - Judd M. Aiken
- Centre for Prions and Protein Folding Diseases, Edmonton, Alberta, Canada
| |
Collapse
|
41
|
Gene expression analysis in distinct regions of the central nervous system during the development of SSBP/1 sheep scrapie. Vet Microbiol 2011; 147:42-8. [DOI: 10.1016/j.vetmic.2010.05.043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Revised: 05/25/2010] [Accepted: 05/28/2010] [Indexed: 11/24/2022]
|
42
|
Huzarewich RLCH, Medina S, Robertson C, Parchaliuk D, Booth SA. Transcriptional modulation in a leukocyte-depleted splenic cell population during prion disease. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2011; 74:1504-1520. [PMID: 22043911 DOI: 10.1080/15287394.2011.618979] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Prion replication in the periphery precedes neuroinvasion in many experimental rodent scrapie models, and in natural sheep scrapie and chronic wasting disease (CWD) in cervids. Prions propagate in the germinal centers of secondary lymphoid organs and are strongly associated with follicular dendritic cells (FDC) and possibly circulating dendritic cells and macrophages. Given the importance of lymphoid organs in prion disease transmission and pathogenesis, gene expression studies may reveal host factors or biological pathways related to prion replication and accumulation. A procedure was developed to enrich for FDC, dendritic cells, and macrophages prior to the investigation of transcriptional alterations in murine splenic cells during prion pathogenesis. In total, 1753 transcripts exhibited fold changes greater than three (false discovery rates less than 2%) in this population isolated from spleens of prion-infected versus uninfected mice. The gene for the small leucine-rich proteoglycan decorin (DCN) was one of the genes most overexpressed in infected mice, and the splenic protein levels mirrored this in mice infected with scrapie as well as bovine spongiform encephalopathy (BSE) and variant Creutzfeldt-Jakob disease (vCJD). A number of groups of functionally related genes were also significantly decreased in infected spleens. These included genes related to iron metabolism and homeostasis, pathways that have also been implicated in prion pathogenesis in the brain. These gene expression alterations provide insights into the molecular mechanisms underlying prion disease pathogenesis and may serve as a pool of potential surrogate markers for the early detection and diagnosis of some prion diseases.
Collapse
Affiliation(s)
- Rhiannon L C H Huzarewich
- Molecular PathoBiology, National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada
| | | | | | | | | |
Collapse
|
43
|
Application of "omics" to prion biomarker discovery. J Biomed Biotechnol 2010; 2010:613504. [PMID: 20224650 PMCID: PMC2833310 DOI: 10.1155/2010/613504] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2009] [Revised: 12/03/2009] [Accepted: 12/30/2009] [Indexed: 02/01/2023] Open
Abstract
The advent of genomics and proteomics has been a catalyst for the discovery of biomarkers able to discriminate biological processes such as the pathogenesis of complex diseases. Prompt detection of prion diseases is particularly desirable given their transmissibility, which is responsible for a number of human health risks stemming from exogenous sources of prion protein. Diagnosis relies on the ability to detect the biomarker PrPSc, a pathological isoform of the host protein PrPC, which is an essential component of the infectious prion. Immunochemical detection of PrPSc is specific and sensitive enough for antemortem testing of brain tissue, however, this is not the case in accessible biological fluids or for the detection of recently identified novel prions with unique biochemical properties. A complementary approach to the detection of PrPSc itself is to identify alternative, “surrogate” gene or protein biomarkers indicative of disease. Biomarkers are also useful to track the progress of disease, especially important in the assessment of therapies, or to identify individuals “at risk”. In this review we provide perspective on current progress and pitfalls in the use of “omics” technologies to screen body fluids and tissues for biomarker discovery in prion diseases.
Collapse
|
44
|
Benetti F, Gasperini L, Zampieri M, Legname G. Gene expression profiling to identify druggable targets in prion diseases. Expert Opin Drug Discov 2010; 5:177-202. [PMID: 22822917 DOI: 10.1517/17460440903544449] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
IMPORTANCE OF THE FIELD Despite many recent advances in prion research, the molecular mechanisms by which prions cause neurodegeneration have not been established. In fact, the complexity and the novelty characterizing this class of disorders pose a huge challenge to drug discovery. Pharmacogenomics has recently adopted high-throughput transcriptome analyses to predict potential drug target candidates, with promising results in various fields of medicine. AREAS COVERED IN THIS REVIEW The present work offers an overview of the transcriptional alterations induced by prion infection in different biological systems. Hereafter, therapeutic approaches are discussed in light of the identified altered processes. WHAT THE READER WILL GAIN This review offers readers a detailed overview on microarray analyses, taking into account their advantages and limitations. Our work can help readers, from many research areas, to design a suitable microarray experiment. TAKE HOME MESSAGE So far, drugs acting on the pathways identified by microarray analysis have not been found to be effective in prion diseases therapy. An integration of gene expression profiling, proteomics and physiology should be applied to pursue this aim.
Collapse
Affiliation(s)
- Federico Benetti
- Laboratory of Prion Biology, Neurobiology Sector, Scuola Internazionale Superiore di Studi Avanzati-International School of Advanced Studies (SISSA-ISAS), Edificio Q1, Basovizza, Trieste, Italy
| | | | | | | |
Collapse
|
45
|
Lyahyai J, Serrano C, Ranera B, Badiola JJ, Zaragoza P, Martin-Burriel I. Effect of Scrapie on the Stability of Housekeeping Genes. Anim Biotechnol 2009; 21:1-13. [DOI: 10.1080/10495390903323851] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
46
|
An integrated systems analysis implicates EGR1 downregulation in simian immunodeficiency virus encephalitis-induced neural dysfunction. J Neurosci 2009; 29:12467-76. [PMID: 19812322 DOI: 10.1523/jneurosci.3180-09.2009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Human immunodeficiency virus (HIV)-associated dementia (HAD) is a syndrome occurring in HIV-infected patients with advanced disease that likely develops as a result of macrophage and microglial activation as well as other immune events triggered by virus in the central nervous system. The most relevant experimental model of HAD, rhesus macaques exhibiting simian immunodeficiency virus (SIV) encephalitis (SIVE), closely reproduces the human disease and has been successfully used to advance our understanding of mechanisms underlying HAD. In this study we integrate gene expression data from uninfected and SIV-infected hippocampus with a human protein interaction network and discover modules of genes whose expression patterns distinguish these two states, to facilitate identification of neuronal genes that may contribute to SIVE/HIV cognitive deficits. Using this approach we identify several downregulated candidate genes and select one, EGR1, a key molecule in hippocampus-related learning and memory, for further study. We show that EGR1 is downregulated in SIV-infected hippocampus and that it can be downregulated in differentiated human neuroblastoma cells by treatment with CCL8, a product of activated microglia. Integration of expression data with protein interaction data to discover discriminatory modules of interacting proteins can be usefully used to prioritize differentially expressed genes for further study. Investigation of EGR1, selected in this manner, indicates that its downregulation in SIVE may occur as a consequence of the host response to infection, leading to deficits in cognition.
Collapse
|
47
|
Bach C, Gilch S, Rost R, Greenwood AD, Horsch M, Hajj GNM, Brodesser S, Facius A, Schädler S, Sandhoff K, Beckers J, Leib-Mösch C, Schätzl HM, Vorberg I. Prion-induced activation of cholesterogenic gene expression by Srebp2 in neuronal cells. J Biol Chem 2009; 284:31260-9. [PMID: 19748890 DOI: 10.1074/jbc.m109.004382] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Prion diseases are neurodegenerative diseases associated with the accumulation of a pathogenic isoform of the host-encoded prion protein. The cellular responses to prion infection are not well defined. By performing microarray analysis on cultured neuronal cells infected with prion strain 22L, in the group of up-regulated genes we observed predominantly genes of the cholesterol pathway. Increased transcript levels of at least nine enzymes involved in cholesterol synthesis, including the gene for the rate-limiting hydroxymethylglutaryl-CoA reductase, were detected. Up-regulation of cholesterogenic genes was attributable to a prion-dependent increase in the amount and activity of the sterol regulatory element-binding protein Srebp2, resulting in elevated levels of total and free cellular cholesterol. The up-regulation of cholesterol biosynthesis appeared to be a characteristic response of neurons to prion challenge, as cholesterogenic transcripts were also elevated in persistently infected GT-1 cells and prion-exposed primary hippocampal neurons but not in microglial cells and primary astrocytes. These results convincingly demonstrate that prion propagation not only depends on the availability of cholesterol but that neuronal cells themselves respond to prions with specific up-regulation of cholesterol biosynthesis.
Collapse
Affiliation(s)
- Christian Bach
- Institute of Virology, Technische Universität München, Trogerstrasse 30, 81675 Munich, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Transcriptional changes in the brains of cattle orally infected with the bovine spongiform encephalopathy agent precede detection of infectivity. J Virol 2009; 83:9464-73. [PMID: 19587050 DOI: 10.1128/jvi.00352-09] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bovine spongiform encephalopathy (BSE) is a fatal, transmissible, neurodegenerative disease of cattle. BSE can be transmitted experimentally between cattle through the oral route, and in this study, brain tissue samples from animals at different time points postinoculation were analyzed for changes in gene expression. The aims of this study were to identify differentially regulated genes during the progression of BSE using microarray-based gene expression profiling and to understand the effect of prion pathogenesis on gene expression. A total of 114 genes were found to be differentially regulated over the time course of the infection, and many of these 114 genes encode proteins involved in immune response, apoptosis, cell adhesion, stress response, and transcription. This study also revealed a broad correlation between gene expression profiles and the progression of BSE in cattle. At 21 months postinoculation, the largest number of differentially regulated genes was detected, suggesting that there are many pathogenic processes in the animal brain even prior to the detection of infectivity in the central nervous systems of these orally infected cattle. Moreover, evidence is presented to suggest that it is possible to predict the infectious status of animals using the expression profiles from this study.
Collapse
|
49
|
Stanton JB, Knowles DP, Call DR, Mathison BA, Baszler TV. Limited transcriptional response of ovine microglia to prion accumulation. Biochem Biophys Res Commun 2009; 386:345-50. [PMID: 19523453 DOI: 10.1016/j.bbrc.2009.06.030] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Accepted: 06/08/2009] [Indexed: 01/22/2023]
Abstract
The conversion of normal cellular prion protein to disease-associated prion protein (PrP(Sc)) is a fundamental component of prion disease pathogenesis. The molecular mechanisms contributing to prion conversion and the impact of PrP(Sc) accumulation on cellular biology are not fully understood. To further define the molecular changes associated with PrP(Sc) accumulation in cultured cells, the transcriptional profile of PrP(Sc)-accumulating primary ovine microglia was compared to the profile of PrP(Sc)-lacking microglia using the Affymetrix Bovine Genome Array. The experimental design included three biological replicates, each with three technical replicates, and samples that were collected at the point of near maximal PrP(Sc) accumulation levels as measured by ELISA. The array analysis revealed only 19 upregulated genes and 30 downregulated genes in PrP(Sc)-accumulating microglia. The results support the hypothesis that chronic PrP(Sc) accumulation in cultured microglia results in a limited transcriptional response.
Collapse
Affiliation(s)
- James B Stanton
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA 99164-7040, USA.
| | | | | | | | | |
Collapse
|
50
|
Moody LR, Herbst AJ, Yoo HS, Vanderloo JP, Aiken JM. Comparative prion disease gene expression profiling using the prion disease mimetic, cuprizone. Prion 2009; 3:99-109. [PMID: 19535908 DOI: 10.4161/pri.3.2.9059] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Identification of genes expressed in response to prion infection may elucidate biomarkers for disease, identify factors involved in agent replication, mechanisms of neuropathology and therapeutic targets. Although several groups have sought to identify gene expression changes specific to prion disease, expression profiles rife with cell population changes have consistently been identified. Cuprizone, a neurotoxicant, qualitatively mimics the cell population changes observed in prion disease, resulting in both spongiform change and astrocytosis. The use of cuprizone-treated animals as an experimental control during comparative expression profiling allows for the identification of transcripts whose expression increases during prion disease and remains unchanged during cuprizone-triggered neuropathology. In this study, expression profiles from the brains of mice preclinically and clinically infected with Rocky Mountain Laboratory (RML) mouse-adapted scrapie agent and age-matched controls were profiled using Affymetrix gene arrays. In total, 164 genes were differentially regulated during prion infection. Eighty-three of these transcripts have been previously undescribed as differentially regulated during prion disease. A 0.4% cuprizone diet was utilized as a control for comparative expression profiling. Cuprizone treatment induced spongiosis and astrocyte proliferation as indicated by glial fibrillary acidic protein (Gfap) transcriptional activation and immunohistochemistry. Gene expression profiles from brain tissue obtained from cuprizone-treated mice identified 307 differentially regulated transcript changes. After comparative analysis, 17 transcripts unaffected by cuprizone treatment but increasing in expression from preclinical to clinical prion infection were identified. Here we describe the novel use of the prion disease mimetic, cuprizone, to control for cell population changes in the brain during prion infection.
Collapse
Affiliation(s)
- Laura R Moody
- Program in Cellular and Molecular Biology and Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, USA
| | | | | | | | | |
Collapse
|