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Censi ST, Mariani-Costantini R, Granzotto A, Tomassini V, Sensi SL. Endogenous retroviruses in multiple sclerosis: A network-based etiopathogenic model. Ageing Res Rev 2024; 99:102392. [PMID: 38925481 DOI: 10.1016/j.arr.2024.102392] [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: 04/08/2024] [Revised: 06/10/2024] [Accepted: 06/19/2024] [Indexed: 06/28/2024]
Abstract
The present perspective article proposes an etiopathological model for multiple sclerosis pathogenesis and progression associated with the activation of human endogenous retroviruses. We reviewed preclinical, clinical, epidemiological, and evolutionary evidence indicating how the complex, multi-level interplay of genetic traits and environmental factors contributes to multiple sclerosis. We propose that endogenous retroviruses transactivation acts as a critical node in disease development. We also discuss the rationale for combined anti-retroviral therapy in multiple sclerosis as a disease-modifying therapeutic strategy. Finally, we propose that the immuno-pathogenic process triggered by endogenous retrovirus activation can be extended to aging and aging-related neurodegeneration. In this regard, endogenous retroviruses can be envisioned to act as epigenetic noise, favoring the proliferation of disorganized cellular subpopulations and accelerating system-specific "aging". Since inflammation and aging are two sides of the same coin (plastic dis-adaptation to external stimuli with system-specific degree of freedom), the two conditions may be epiphenomenal products of increased epigenomic entropy. Inflammation accelerates organ-specific aging, disrupting communication throughout critical systems of the body and producing symptoms. Overlapping neurological symptoms and syndromes may emerge from the activity of shared molecular networks that respond to endogenous retroviruses' reactivation.
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Affiliation(s)
- Stefano T Censi
- Department of Neuroscience, Imaging, and Clinical Sciences, "G. d'Annunzio" University, Chieti-Pescara, Italy; Institute for Advanced Biomedical Technologies (ITAB), "G. d'Annunzio" University, Chieti-Pescara, Italy.
| | - Renato Mariani-Costantini
- Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University, Chieti-Pescara, Italy
| | - Alberto Granzotto
- Department of Neuroscience, Imaging, and Clinical Sciences, "G. d'Annunzio" University, Chieti-Pescara, Italy; Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University, Chieti-Pescara, Italy
| | - Valentina Tomassini
- Department of Neuroscience, Imaging, and Clinical Sciences, "G. d'Annunzio" University, Chieti-Pescara, Italy; Institute for Advanced Biomedical Technologies (ITAB), "G. d'Annunzio" University, Chieti-Pescara, Italy; Multiple Sclerosis Centre, Institute of Neurology, SS Annunziata Hospital, "G. d'Annunzio" University, Chieti, Italy
| | - Stefano L Sensi
- Department of Neuroscience, Imaging, and Clinical Sciences, "G. d'Annunzio" University, Chieti-Pescara, Italy; Institute for Advanced Biomedical Technologies (ITAB), "G. d'Annunzio" University, Chieti-Pescara, Italy; Center for Advanced Studies and Technology (CAST), "G. d'Annunzio" University, Chieti-Pescara, Italy; Multiple Sclerosis Centre, Institute of Neurology, SS Annunziata Hospital, "G. d'Annunzio" University, Chieti, Italy.
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Bello-Morales R, Andreu S, Ripa I, López-Guerrero JA. HSV-1 and Endogenous Retroviruses as Risk Factors in Demyelination. Int J Mol Sci 2021; 22:ijms22115738. [PMID: 34072259 PMCID: PMC8199333 DOI: 10.3390/ijms22115738] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 12/19/2022] Open
Abstract
Herpes simplex virus type 1 (HSV-1) is a neurotropic alphaherpesvirus that can infect the peripheral and central nervous systems, and it has been implicated in demyelinating and neurodegenerative processes. Transposable elements (TEs) are DNA sequences that can move from one genomic location to another. TEs have been linked to several diseases affecting the central nervous system (CNS), including multiple sclerosis (MS), a demyelinating disease of unknown etiology influenced by genetic and environmental factors. Exogenous viral transactivators may activate certain retrotransposons or class I TEs. In this context, several herpesviruses have been linked to MS, and one of them, HSV-1, might act as a risk factor by mediating processes such as molecular mimicry, remyelination, and activity of endogenous retroviruses (ERVs). Several herpesviruses have been involved in the regulation of human ERVs (HERVs), and HSV-1 in particular can modulate HERVs in cells involved in MS pathogenesis. This review exposes current knowledge about the relationship between HSV-1 and human ERVs, focusing on their contribution as a risk factor for MS.
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Affiliation(s)
- Raquel Bello-Morales
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain; (S.A.); (I.R.); (J.A.L.-G.)
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Cantoblanco, 28049 Madrid, Spain
- Correspondence:
| | - Sabina Andreu
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain; (S.A.); (I.R.); (J.A.L.-G.)
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Cantoblanco, 28049 Madrid, Spain
| | - Inés Ripa
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain; (S.A.); (I.R.); (J.A.L.-G.)
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Cantoblanco, 28049 Madrid, Spain
| | - José Antonio López-Guerrero
- Departamento de Biología Molecular, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain; (S.A.); (I.R.); (J.A.L.-G.)
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Cantoblanco, 28049 Madrid, Spain
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Kristensen MK, Christensen T. Regulation of the expression of human endogenous retroviruses: elements in fetal development and a possible role in the development of cancer and neurological diseases. APMIS 2021; 129:241-253. [PMID: 33683784 DOI: 10.1111/apm.13130] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 03/03/2021] [Indexed: 12/14/2022]
Abstract
Human endogenous retroviruses (HERVs) are remnants of ancient retroviral germline infections. Most HERV sequences are silenced in somatic cells, but interest is emerging on the involvement of HERV derived transcripts and proteins in human physiology and disease. A HERV-W encoded protein, syncytin-1, has been co-opted into fetal physiology, where it plays a role in trophoblast formation. Altered HERV transcription and expression of HERV derived proteins are associated with various cancer types and neurological diseases such as multiple sclerosis (MS). The implication of HERVs as potential mediators of both health and disease suggests important roles of regulatory mechanisms and alterations of these in physiological and pathological processes. The regulation of HERV sequences is mediated by a wide variety of mechanisms, and the focus of this review is on selected aspects of these, including epigenetic mechanisms such as CpG methylation and histone modifications of the HP1-H3K9me axis, viral transactivation events, and regulatory perspectives of transient stimuli in the microenvironment. Increasing knowledge of the regulation of HERV sequences will not only contribute to the understanding of complex pathogeneses, but also may pinpoint potential targets for better diagnosis and treatment in complex diseases as MS.
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Tatar E, Cengiz Y, Pektas E, Eroglu B, Turkeri Birant G, Tasli F. Interferon-β therapy and C4d glomerulopathy: Case report and literature review. Nephrology (Carlton) 2019; 25:507-508. [PMID: 31775180 DOI: 10.1111/nep.13675] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 10/23/2019] [Accepted: 10/27/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Erhan Tatar
- Department of Nephrology, University of Health Sciences, Izmir Bozyaka Education and Research Hospital, Izmir, Turkey
| | - Yalcın Cengiz
- Department of Internal Medicine, University of Health Sciences, Izmir Bozyaka Education and Research Hospital, Izmir, Turkey
| | - Erengul Pektas
- Department of Internal Medicine, University of Health Sciences, Izmir Bozyaka Education and Research Hospital, Izmir, Turkey
| | - Busra Eroglu
- Department of Internal Medicine, University of Health Sciences, Izmir Bozyaka Education and Research Hospital, Izmir, Turkey
| | - Gulen Turkeri Birant
- Department of Nephrology, University of Health Sciences, Izmir Bozyaka Education and Research Hospital, Izmir, Turkey
| | - Funda Tasli
- Department of Pathology, University of Health Sciences, Izmir Bozyaka Education and Research Hospital, Izmir, Turkey
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Abstract
PURPOSE OF THE REVIEW The aim of this review is to discuss recent data pointing at an involvement of human endogenous retroviruses (HERVs) in type 1 diabetes (T1D) onset and progression. RECENT FINDINGS The envelope protein of HERV-W family, named HERV-W-Env, was detected in pancreata from T1D patients and was shown to display pro-inflammatory properties and direct toxicity toward pancreatic beta cells. The etiopathogenesis of T1D remains elusive, even if conventional environmental viral infections have been recurrently involved. Nonetheless, a new category of pathogens may provide the missing link between genetic susceptibility and environmental factors long thought to contribute to T1D onset. A number of studies have now shown that HERV sequences, which are normally inactivated or repressed in the human genome, could be activated by environmental viruses. Thus, if similarly activated by viruses associated with T1D, disregarded HERV genes may underlie T1D genetic susceptibility. Moreover, once expressed, HERV elements may display broad pathogenic properties, which identify them as potential new therapeutic targets.
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Affiliation(s)
- Sandrine Levet
- GeNeuro Innovation, 60 avenue Rockefeller, 69008 Lyon, France
| | - B. Charvet
- GeNeuro Innovation, 60 avenue Rockefeller, 69008 Lyon, France
| | - A. Bertin
- Faculté de Médecine, CHU Lille, Laboratoire de Virologie EA3610, Université Lille, F-59000 Lille, France
| | - A. Deschaumes
- Faculté de Médecine, CHU Lille, Laboratoire de Virologie EA3610, Université Lille, F-59000 Lille, France
| | - H. Perron
- GeNeuro Innovation, 60 avenue Rockefeller, 69008 Lyon, France
- Laboratoire des déficits immunitaires, University of Lyon, Lyon, France
- Plan-les-Ouates, GeNeuro SA, Geneva, Switzerland
| | - D. Hober
- Faculté de Médecine, CHU Lille, Laboratoire de Virologie EA3610, Université Lille, F-59000 Lille, France
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Expression of HERV Genes as Possible Biomarker and Target in Neurodegenerative Diseases. Int J Mol Sci 2019; 20:ijms20153706. [PMID: 31362360 PMCID: PMC6696274 DOI: 10.3390/ijms20153706] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2019] [Revised: 07/22/2019] [Accepted: 07/24/2019] [Indexed: 02/07/2023] Open
Abstract
Human endogenous retroviruses (HERVs) are genetic parasites, in-between genetics and environment. Few HERVs retain some coding capability. Sometimes, the host has the advantage of some HERV genes; conversely, HERVs may contribute to pathogenesis. The expression of HERVs depends on several factors, and is regulated epigenetically by stimuli such as inflammation, viral and microbial infections, etc. Increased expression of HERVs occurs in physiological and pathological conditions, in one or more body sites. Several diseases have been attributed to one or more HERVs, particularly neurological diseases. The key problem is to differentiate the expression of a HERV as cause or effect of a disease. To be used as a biomarker, a correlation between the expression of a certain HERV and the disease onset and/or behavior must be found. The greater challenge is to establish a pathogenic role. The criteria defining causal connections between HERVs and diseases include the development of animal models, and disease modulation in humans, by anti-HERV therapeutic antibody. So far, statistically significant correlations between HERVs and diseases have been achieved for HERV-W and multiple sclerosis; disease reproduction in transgenic animals was achieved for HERV-W and multiple sclerosis, and for HERV-K and amyotrophic lateral sclerosis. Clinical trials for both diseases are in progress.
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Küry P, Nath A, Créange A, Dolei A, Marche P, Gold J, Giovannoni G, Hartung HP, Perron H. Human Endogenous Retroviruses in Neurological Diseases. Trends Mol Med 2018; 24:379-394. [PMID: 29551251 PMCID: PMC7185488 DOI: 10.1016/j.molmed.2018.02.007] [Citation(s) in RCA: 175] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 02/12/2018] [Accepted: 02/15/2018] [Indexed: 12/12/2022]
Abstract
The causes of multiple sclerosis and amyotrophic lateral sclerosis have long remained elusive. A new category of pathogenic components, normally dormant within human genomes, has been identified: human endogenous retroviruses (HERVs). These represent ∼8% of the human genome, and environmental factors have reproducibly been shown to trigger their expression. The resulting production of envelope (Env) proteins from HERV-W and HERV-K appears to engage pathophysiological pathways leading to the pathognomonic features of MS and ALS, respectively. Pathogenic HERV elements may thus provide a missing link in understanding these complex diseases. Moreover, their neutralization may represent a promising strategy to establish novel and more powerful therapeutic approaches.
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Affiliation(s)
- Patrick Küry
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany
| | - Avindra Nath
- Section of infections of the Nervous System, National Institute of Neurological Diseases and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, MD, USA
| | - Alain Créange
- Service de Neurologie, Groupe Hospitalier Henri Mondor, Assistance Publique Hopitaux de Paris (APHP), Université Paris Est, Créteil, France
| | - Antonina Dolei
- Department of Virology, University of Sassari, Sassari, Italy
| | - Patrice Marche
- Institute for Advanced Biosciences (IAB), University of Grenoble-Alpes, La Tronche, France; Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1209, La Tronche, France
| | - Julian Gold
- Centre for Neuroscience and Trauma, Blizard Institute, Queen Mary University, London, UK; The Albion Centre, Prince of Wales Hospital, Sydney, Australia
| | - Gavin Giovannoni
- Centre for Neuroscience and Trauma, Blizard Institute, Queen Mary University, London, UK
| | - Hans-Peter Hartung
- Department of Neurology, Medical Faculty, Heinrich-Heine-University, Düsseldorf, Germany.
| | - Hervé Perron
- Geneuro, Plan les Ouates, Geneva, Switzerland; University of Lyon, Lyon, France
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Grandi N, Tramontano E. HERV Envelope Proteins: Physiological Role and Pathogenic Potential in Cancer and Autoimmunity. Front Microbiol 2018; 9:462. [PMID: 29593697 PMCID: PMC5861771 DOI: 10.3389/fmicb.2018.00462] [Citation(s) in RCA: 135] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 02/27/2018] [Indexed: 12/29/2022] Open
Abstract
Human endogenous retroviruses (HERVs) are relics of ancient infections accounting for about the 8% of our genome. Despite their persistence in human DNA led to the accumulation of mutations, HERVs are still contributing to the human transcriptome, and a growing number of findings suggests that their expression products may have a role in various diseases. Among HERV products, the envelope proteins (Env) are currently highly investigated for their pathogenic properties, which could likely be participating to several disorders with complex etiology, particularly in the contexts of autoimmunity and cancer. In fact, HERV Env proteins have been shown, on the one side, to trigger both innate and adaptive immunity, prompting inflammatory, cytotoxic and apoptotic reactions; and, on the other side, to prevent the immune response activation, presenting immunosuppressive properties and acting as immune downregulators. In addition, HERV Env proteins have been shown to induce abnormal cell-cell fusion, possibly contributing to tumor development and metastasizing processes. Remarkably, even highly defective HERV env genes and alternative env splicing variants can provide further mechanisms of pathogenesis. A well-known example is the HERV-K(HML2) env gene that, depending on the presence or the absence of a 292-bp deletion, can originate two proteins of different length (Np9 and Rec) proposed to have oncogenic properties. The understanding of their involvement in complex pathological disorders made HERV Env proteins potential targets for therapeutic interventions. Of note, a monoclonal antibody directed against a HERV-W Env is currently under clinical trial as therapeutic approach for multiple sclerosis, representing the first HERV-based treatment. The present review will focus on the current knowledge of the HERV Env expression, summarizing its role in human physiology and its possible pathogenic effects in various cancer and autoimmune disorders. It moreover analyzes HERV Env possible exploitation for the development of innovative therapeutic strategies.
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Affiliation(s)
- Nicole Grandi
- Laboratory of Molecular Virology, Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Enzo Tramontano
- Laboratory of Molecular Virology, Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
- Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche, Cagliari, Italy
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Abstract
Two human endogenous retroviruses of the HERV-W family are proposed as multiple sclerosis (MS) co-factors: MS-associated retrovirus (MSRV) and ERVWE1, whose env proteins showed several potentially neuropathogenic features, in vitro and in animal models. Phase II clinical trials against HERV-Wenv are ongoing. HERV-W/MSRV was repeatedly found in MS patients, in striking parallel with MS stages, active/remission phases, and therapy outcome. The HERV-Wenv protein is highly expressed in active MS plaques. Early MSRV presence in spinal fluids predicted worst MS progression 10 years in advance. Effective anti-MS therapies strongly reduced MSRV/Syncytin-1/HERV-W expression. The Epstein–Barr virus (EBV) activates HERV-W/MSRV in vitro and in vivo, in patients with infectious mononucleosis and controls with high anti-EBNA1-IgG titers. Thus, the two main EBV/MS links (infectious mononucleosis and high anti-EBNA1-IgG titers) are paralleled by activation of HERV-W/MSRV. It is hypothesized that EBV may act as initial trigger of future MS, years later, by activating MSRV, which would act as direct neuropathogenic effector, before and during MS.
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Gjelstrup MC, Stilund M, Petersen T, Møller HJ, Petersen EL, Christensen T. Subsets of activated monocytes and markers of inflammation in incipient and progressed multiple sclerosis. Immunol Cell Biol 2017; 96:160-174. [PMID: 29363161 PMCID: PMC5836924 DOI: 10.1111/imcb.1025] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 09/14/2017] [Accepted: 10/10/2017] [Indexed: 12/26/2022]
Abstract
Multiple sclerosis (MS) is an immune mediated, inflammatory and demyelinating disease of the central nervous system (CNS). Substantial evidence points toward monocytes and macrophages playing prominent roles early in disease, mediating both pro- and anti-inflammatory responses. Monocytes are subdivided into three subsets depending on the expression of CD14 and CD16, representing different stages of inflammatory activation. To investigate their involvement in MS, peripheral blood mononuclear cells from 40 patients with incipient or progressed MS and 20 healthy controls were characterized ex vivo. In MS samples, we demonstrate a highly significant increase in nonclassical monocytes (CD14+CD16++), with a concomitant significant reduction in classical monocytes (CD14++CD16-) compared with healthy controls. Also, a significant reduction in the surface expression of CD40, CD163, and CD192 was found, attributable to the upregulation of the nonclassical monocytes. In addition, significantly increased levels of human endogenous retrovirus (HERV) envelope (Env) epitopes, encoded by both HERV-H/F and HERV-W, were specifically found on nonclassical monocytes from patients with MS; emphasizing their involvement in MS disease. In parallel, serum and cerebrospinal fluid (CSF) samples were analyzed for soluble biomarkers of inflammation and neurodegeneration. For sCD163 versus CD163, no significant correlations were found, whereas highly significant correlations between levels of soluble neopterine and the intermediate monocyte (CD14++CD16+) population was found, as were correlations between levels of soluble osteopontin and the HERV Env expression on nonclassical monocytes. The results from this study emphasize the relevance of further focus on monocyte subsets, particularly the nonclassical monocytes in monitoring of inflammatory diseases.
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Affiliation(s)
- Mikkel Carstensen Gjelstrup
- Department of Biomedicine, Aarhus University, Bartholin Building, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark
| | - Morten Stilund
- Department of Biomedicine, Aarhus University, Bartholin Building, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark.,Department of Neurology, Aarhus University Hospital, Nørrebrogade 44, DK-8000, Aarhus C, Denmark
| | - Thor Petersen
- Department of Neurology, Aarhus University Hospital, Nørrebrogade 44, DK-8000, Aarhus C, Denmark
| | - Holger Jon Møller
- Department of Clinical Biochemistry, Aarhus University Hospital, Palle Juul Jensens Boulevard 99, DK-8200, Aarhus N, Denmark
| | - Eva Lykke Petersen
- Department of Biomedicine, Aarhus University, Bartholin Building, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark
| | - Tove Christensen
- Department of Biomedicine, Aarhus University, Bartholin Building, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark
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Christensen T. Human endogenous retroviruses in the aetiology of MS. Acta Neurol Scand 2017; 136 Suppl 201:18-21. [PMID: 29068488 DOI: 10.1111/ane.12836] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2017] [Indexed: 12/25/2022]
Abstract
Several lines of investigation have provided strong indications for an association between the immune-mediated, neurologic disease multiple sclerosis (MS) and human endogenous retroviruses (HERVs). Whether the relationship is causal is yet to be established. Endogenous retroviruses are pathogenic-in other species than the human. Several aspects of the activation and involvement of specific HERV families (HERV-H/F and HERV-W/MSRV) have been documented, both for cells in the periphery and in the central nervous system. Specific HERV-encoded genes and certain gene products (envelope proteins, Envs) appear strongly associated with the disease and have pathogenic potential. Most HERV sequences are non-functional, whereas some HERV loci have coding potential but remain quiescent in non-pathological conditions, so the importance of regulatory pathways and epigenetics involved in regulating HERV activation, de-repression, and also involvement of retroviral restriction factors, is emerging. Disease intervention by means of antiretrovirals has potential as a novel therapeutic strategy in MS treatment; this is compounded by the apparently reduced risk of MS in HIV infection as a consequence of therapy. Extensive studies of HERVs, their role in neurologic diseases, and their potential as therapeutic targets are needed.
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Affiliation(s)
- T. Christensen
- Department of Biomedicine; Aarhus University; Aarhus Denmark
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12
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Retroviral envelope proteins: Involvement in neuropathogenesis. J Neurol Sci 2017; 380:151-163. [DOI: 10.1016/j.jns.2017.07.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 06/23/2017] [Accepted: 07/18/2017] [Indexed: 02/07/2023]
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Grandi N, Tramontano E. Type W Human Endogenous Retrovirus (HERV-W) Integrations and Their Mobilization by L1 Machinery: Contribution to the Human Transcriptome and Impact on the Host Physiopathology. Viruses 2017; 9:v9070162. [PMID: 28653997 PMCID: PMC5537654 DOI: 10.3390/v9070162] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/08/2017] [Accepted: 06/20/2017] [Indexed: 01/07/2023] Open
Abstract
Human Endogenous Retroviruses (HERVs) are ancient infection relics constituting ~8% of our DNA. While HERVs’ genomic characterization is still ongoing, impressive amounts of data have been obtained regarding their general expression across tissues. Among HERVs, one of the most studied is the W group, which is the sole HERV group specifically mobilized by the long interspersed element-1 (LINE-1) machinery, providing a source of novel insertions by retrotransposition of HERV-W processed pseudogenes, and comprising a member encoding a functional envelope protein coopted for human placentation. The HERV-W group has been intensively investigated for its putative role in several diseases, such as cancer, inflammation, and autoimmunity. Despite major interest in the link between HERV-W expression and human pathogenesis, no conclusive correlation has been demonstrated so far. In general, (i) the absence of a proper identification of the specific HERV-W sequences expressed in a given condition; and (ii) the lack of studies attempting to connect the various observations in the same experimental conditions are the major problems preventing the definitive assessment of the HERV-W impact on human physiopathology. In this review, we summarize the current knowledge on the HERV-W group presence within the human genome and its expression in physiological tissues as well as in the main pathological contexts.
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Affiliation(s)
- Nicole Grandi
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato SS554, 09042 Monserrato, Cagliari, Italy.
| | - Enzo Tramontano
- Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato SS554, 09042 Monserrato, Cagliari, Italy.
- Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche (CNR), 09042 Monserrato, Cagliari, Italy.
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14
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Christensen T. Human endogenous retroviruses in neurologic disease. APMIS 2016; 124:116-26. [DOI: 10.1111/apm.12486] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2015] [Accepted: 10/26/2015] [Indexed: 12/13/2022]
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15
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Varadé J, García-Montojo M, de la Hera B, Camacho I, García-Martínez MÁ, Arroyo R, Álvarez-Lafuente R, Urcelay E. Multiple sclerosis retrovirus-like envelope gene: Role of the chromosome 20 insertion. BBA CLINICAL 2015; 3:162-7. [PMID: 26675450 PMCID: PMC4669942 DOI: 10.1016/j.bbacli.2015.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/09/2015] [Accepted: 02/12/2015] [Indexed: 11/18/2022]
Abstract
Background The genetic basis involved in multiple sclerosis (MS) susceptibility was not completely revealed by genome-wide association studies. Part of it could lie in repetitive sequences, as those corresponding to human Endogenous Retroviruses (HERVs). Retrovirus-like particles were isolated from MS patients and the genome of the MS-associated retrovirus (MSRV) was the founder of the HERV-W family. We aimed to ascertain which chromosomal origin encodes the pathogenic ENV protein by genomic analysis of the HERV-W insertions. Methods/results In silico analyses allowed to uncover putative open reading frames containing the specific sequence previously reported for MSRV-like envelope (env) detection. Out of the 261 genomic insertions of HERV-W env, only 9 copies harbor the specific primers and probe featuring MSRV-like env. The copy from chromosome 20 was further studied considering its size, a truncated homologue of the functional HERV-W env sequence encoding syncytin. High Resolution Melting analysis of this sequence identified two single nucleotide polymorphisms, subsequently genotyped by Taqman chemistry in 668 MS patients and 678 healthy controls. No significant association of these polymorphisms with MS risk was evidenced. Transcriptional activity of this MSRV-like env copy was detected in peripheral blood mononuclear cells from patients and controls. RNA expression levels of chromosome 20-specific MSRV-like env did not show significant differences between MS patients and controls, neither were related to genotypes of the two mentioned polymorphisms. Conclusions The lack of association with MS risk of the identified polymorphisms together with the transcription results discard chromosome 20 as genomic origin of MSRV-like env. The chr.20 HERV-W env copy encodes a truncated homologue of the functional syncytin. Two single nucleotide polymorphisms were identified in this sequence by High Resolution Melting. No association of these polymorphisms with MS susceptibility was evidenced. RNA expression of the chr. 20 HERV-W env copy did not show association with MS risk. The chr. 20 HERV-W env copy does not seem to be an origin of MSRV ENV protein.
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Affiliation(s)
- Jezabel Varadé
- Immunology Dept., Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), 28040 Madrid. Spain
| | - Marta García-Montojo
- Multiple Sclerosis Unit, Neurology Dept., Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), 28040 Madrid. Spain
| | - Belén de la Hera
- Immunology Dept., Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), 28040 Madrid. Spain
| | - Iris Camacho
- Immunology Dept., Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), 28040 Madrid. Spain
| | - Mª. Ángel García-Martínez
- Immunology Dept., Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), 28040 Madrid. Spain
| | - Rafael Arroyo
- Multiple Sclerosis Unit, Neurology Dept., Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), 28040 Madrid. Spain
| | - Roberto Álvarez-Lafuente
- Multiple Sclerosis Unit, Neurology Dept., Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), 28040 Madrid. Spain
| | - Elena Urcelay
- Immunology Dept., Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), 28040 Madrid. Spain
- Corresponding author at: Immunology Department, Hospital Clínico San Carlos, IdISSC, Martin Lagos s/n, 28040 Madrid, Spain. Tel.: + 34 91 330 3000x7171; fax: + 34 91 330 3879.
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Shi L, Zhang Z, Yu AM, Wang W, Wei Z, Akhter E, Maurer K, Reis PC, Song L, Petri M, Sullivan KE. The SLE transcriptome exhibits evidence of chronic endotoxin exposure and has widespread dysregulation of non-coding and coding RNAs. PLoS One 2014; 9:e93846. [PMID: 24796678 PMCID: PMC4010412 DOI: 10.1371/journal.pone.0093846] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 03/07/2014] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND Gene expression studies of peripheral blood mononuclear cells from patients with systemic lupus erythematosus (SLE) have demonstrated a type I interferon signature and increased expression of inflammatory cytokine genes. Studies of patients with Aicardi Goutières syndrome, commonly cited as a single gene model for SLE, have suggested that accumulation of non-coding RNAs may drive some of the pathologic gene expression, however, no RNA sequencing studies of SLE patients have been performed. This study was designed to define altered expression of coding and non-coding RNAs and to detect globally altered RNA processing in SLE. METHODS Purified monocytes from eight healthy age/gender matched controls and nine SLE patients (with low-moderate disease activity and lack of biologic drug use or immune suppressive treatment) were studied using RNA-seq. Quantitative RT-PCR was used to validate findings. Serum levels of endotoxin were measured by ELISA. RESULTS We found that SLE patients had diminished expression of most endogenous retroviruses and small nucleolar RNAs, but exhibited increased expression of pri-miRNAs. Splicing patterns and polyadenylation were significantly altered. In addition, SLE monocytes expressed novel transcripts, an effect that was replicated by LPS treatment of control monocytes. We further identified increased circulating endotoxin in SLE patients. CONCLUSIONS Monocytes from SLE patients exhibit globally dysregulated gene expression. The transcriptome is not simply altered by the transcriptional activation of a set of genes, but is qualitatively different in SLE. The identification of novel loci, inducible by LPS, suggests that chronic microbial translocation could contribute to the immunologic dysregulation in SLE, a new potential disease mechanism.
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Affiliation(s)
- Lihua Shi
- The Division of Allergy Immunology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Zhe Zhang
- The Center for Biomedical Informatics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Angela M. Yu
- The Center for Biomedical Informatics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Wei Wang
- Department of Computer Science, New Jersey Institute of Technology, Newark, New Jersey, United States of America
| | - Zhi Wei
- Department of Computer Science, New Jersey Institute of Technology, Newark, New Jersey, United States of America
| | - Ehtisham Akhter
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Kelly Maurer
- The Division of Allergy Immunology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Patrícia Costa Reis
- The Division of Allergy Immunology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Li Song
- The Division of Allergy Immunology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
| | - Michelle Petri
- Division of Rheumatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Kathleen E. Sullivan
- The Division of Allergy Immunology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America
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17
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Douville RN, Nath A. Human endogenous retroviruses and the nervous system. HANDBOOK OF CLINICAL NEUROLOGY 2014; 123:465-85. [PMID: 25015500 DOI: 10.1016/b978-0-444-53488-0.00022-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Renée N Douville
- Department of Microbiology, University of Winnipeg, Winnipeg, Manitoba, Canada
| | - Avindra Nath
- Section of Infections of the Nervous System, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, MD, USA.
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Abstract
Multiple sclerosis (MS) is an inflammatory demyelinating autoimmune disease of the central nervous system (CNS). Although the etiology of MS is unknown, genetic and environmental factors play a role. Infectious pathogens are the likely environmental factors involved in the development of MS. Pathogens associated with the development or exacerbation of MS include bacteria, such as Mycoplasma pneumoniae and Chlamydia pneumoniae, the Staphylococcus aureus-produced enterotoxins that function as superantigens, viruses of the herpes virus (Epstein-Barr virus and human herpesvirus 6) and human endogenous retrovirus (HERV) families and the protozoa Acanthamoeba castellanii. Evidence, from studies with humans and animal models, supporting the association of these various pathogens with the development and/or exacerbation of MS will be discussed along with the potential mechanisms including molecular mimicry, epitope spreading and bystander activation. In contrast, infection with certain parasites such as helminthes (Schistosoma mansoni, Fasciola hepatica, Hymenolepis nana, Trichuris trichiura, Ascaris lumbricoides, Strongyloides stercolaris, Enterobius vermicularis) appears to protect against the development or exacerbation of MS. Evidence supporting the ability of parasitic infections to protect against disease will be discussed along with a brief summary of a recent Phase I clinical trial testing the ability of Trichuris suis ova treatment to improve the clinical course of MS. A complex interaction between the CNS (including the blood-brain barrier), multiple infections with various infectious agents (occurring in the periphery or within the CNS), and the immune response to those various infections may have to be deciphered before the etiology of MS can be fully understood.
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Affiliation(s)
- Jane E Libbey
- Department of Pathology, University of Utah School of Medicine , Salt Lake City, UT , USAxs
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Mameli G, Madeddu G, Mei A, Uleri E, Poddighe L, Delogu LG, Maida I, Babudieri S, Serra C, Manetti R, Mura MS, Dolei A. Activation of MSRV-type endogenous retroviruses during infectious mononucleosis and Epstein-Barr virus latency: the missing link with multiple sclerosis? PLoS One 2013; 8:e78474. [PMID: 24236019 PMCID: PMC3827255 DOI: 10.1371/journal.pone.0078474] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 09/12/2013] [Indexed: 11/28/2022] Open
Abstract
The etiology of multiple sclerosis (MS) is still unclear. The immuno-pathogenic phenomena leading to neurodegeneration are thought to be triggered by environmental (viral?) factors operating on predisposing genetic backgrounds. Among the proposed co-factors are the Epstein Barr virus (EBV), and the potentially neuropathogenic HERV-W/MSRV/Syncytin-1 endogenous retroviruses. The ascertained links between EBV and MS are history of late primary infection, possibly leading to infectious mononucleosis (IM), and high titers of pre-onset IgG against EBV nuclear antigens (anti-EBNA IgG). During MS, there is no evidence of MS-specific EBV expression, while a continuous expression of HERV-Ws occurs, paralleling disease behaviour. We found repeatedly extracellular HERV-W/MSRV and MSRV-specific mRNA sequences in MS patients (in blood, spinal fluid, and brain samples), and MRSV presence/load strikingly paralleled MS stages and active/remission phases. Aim of the study was to verify whether HERV-W might be activated in vivo, in hospitalized young adults with IM symptoms, that were analyzed with respect to expression of HERV-W/MSRV transcripts and proteins. Healthy controls were either EBV-negative or latently EBV-infected with/without high titers of anti-EBNA-1 IgG. The results show that activation of HERV-W/MSRV occurs in blood mononuclear cells of IM patients (2Log10 increase of MSRV-type env mRNA accumulation with respect to EBV-negative controls). When healthy controls are stratified for previous EBV infection (high and low, or no anti-EBNA-1 IgG titers), a direct correlation occurs with MSRV mRNA accumulation. Flow cytometry data show increased percentages of cells exposing surface HERV-Wenv protein, that occur differently in specific cell subsets, and in acute disease and past infection. Thus, the data indicate that the two main links between EBV and MS (IM and high anti-EBNA-1-IgG titers) are paralleled by activation of the potentially neuropathogenic HERV-W/MSRV. These novel findings suggest HERV-W/MSRV activation as the missing link between EBV and MS, and may open new avenues of intervention.
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Affiliation(s)
- Giuseppe Mameli
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Giordano Madeddu
- Department of Clinical and Experimental Medicine, University of Sassari, Sassari, Italy
| | - Alessandra Mei
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Elena Uleri
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Luciana Poddighe
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Lucia G. Delogu
- Department of Chemistry and Pharmacy, University of Sassari, Sassari, Italy
| | - Ivana Maida
- Department of Clinical and Experimental Medicine, University of Sassari, Sassari, Italy
| | - Sergio Babudieri
- Department of Clinical and Experimental Medicine, University of Sassari, Sassari, Italy
| | - Caterina Serra
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
| | - Roberto Manetti
- Department of Clinical and Experimental Medicine, University of Sassari, Sassari, Italy
| | - Maria S. Mura
- Department of Clinical and Experimental Medicine, University of Sassari, Sassari, Italy
| | - Antonina Dolei
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy
- * E-mail:
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20
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Garcia-Montojo M, Dominguez-Mozo M, Arias-Leal A, Garcia-Martinez Á, De las Heras V, Casanova I, Faucard R, Gehin N, Madeira A, Arroyo R, Curtin F, Alvarez-Lafuente R, Perron H. The DNA copy number of human endogenous retrovirus-W (MSRV-type) is increased in multiple sclerosis patients and is influenced by gender and disease severity. PLoS One 2013; 8:e53623. [PMID: 23308264 PMCID: PMC3538585 DOI: 10.1371/journal.pone.0053623] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Accepted: 11/30/2012] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND Multiple sclerosis is an autoimmune disease more prevalent in women than in men. Multiple Sclerosis Associated Retrovirus element (MSRV) is a member of type-W endogenous retrovirus family (HERV-W), known to be associated to MS. Most HERVs are unable to replicate but MSRV expression associated with reverse-transcriptase activity in MS would explain reported DNA copy number increase in MS patients. A potential link between HERV-W copies on chromosome X and gender differential prevalence has been suggested. The present study addresses MSRV-type DNA load in relation with the gender differences and clinical status in MS and healthy controls. RESULTS 178 MS patients (62.9% women) and 124 controls (56.5% women) were included. MSRV env load (copies/pg of DNA) was analyzed by real time qPCR with specific primers and probe for its env gene, in DNA from peripheral blood mononuclear cells (PBMCs). MSRV load was more elevated in MS patients than in controls (p = 4.15e-7). MS women presented higher MSRV load than control women (p = 0.009) and MS men also had higher load than control men (p = 2.77e-6). Besides, women had higher levels than men, both among patients (p = 0.007) and controls (p = 1.24e-6). Concordantly, EDSS and MSSS scores were higher among female patients with an elevated MSRV load (p = 0.03 and p = 0.04, respectively). CONCLUSIONS MSRV increases its copy number in PBMC of MS patients and particularly in women with high clinical scores. This may explain causes underlying the higher prevalence of MS in women. The association with the clinical severity calls for further investigations on MSRV load in PBMCs as a biomarker for MS.
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Affiliation(s)
- Marta Garcia-Montojo
- Multiple Sclerosis Unit, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain.
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Santoni FA, Guerra J, Luban J. HERV-H RNA is abundant in human embryonic stem cells and a precise marker for pluripotency. Retrovirology 2012; 9:111. [PMID: 23253934 PMCID: PMC3558390 DOI: 10.1186/1742-4690-9-111] [Citation(s) in RCA: 152] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Accepted: 12/16/2012] [Indexed: 01/10/2023] Open
Abstract
Background Certain post-translational modifications to histones, including H3K4me3, as well as binding sites for the transcription factor STAT1, predict the site of integration of exogenous gamma-retroviruses with great accuracy and cell-type specificity. Statistical methods that were used to identify chromatin features that predict exogenous gamma-retrovirus integration site selection were exploited here to determine whether cell type-specific chromatin markers are enriched in the vicinity of endogenous retroviruses (ERVs). Results Among retro-elements in the human genome, the gamma-retrovirus HERV-H was highly associated with H3K4me3, though this association was only observed in embryonic stem (ES) cells (p < 10-300) and, to a lesser extent, in induced pluripotent stem (iPS) cells. No significant association was observed in nearly 40 differentiated cell types, nor was any association observed with other retro-elements. Similar strong association was observed between HERV-H and the binding sites within ES cells for the pluripotency transcription factors NANOG, OCT4, and SOX2. NANOG binding sites were located within the HERV-H 5′LTR itself. OCT4 and SOX2 binding sites were within 1 kB and 2 kB of the 5′LTR, respectively. In keeping with these observations, HERV-H RNA constituted 2% of all poly A RNA in ES cells. As ES cells progressed down a differentiation pathway, the levels of HERV-H RNA decreased progressively. RNA-Seq datasets showed HERV-H transcripts to be over 5 kB in length and to have the structure 5′LTR-gag-pro-3′LTR, with no evidence of splicing and no intact open reading frames. Conclusion The developmental regulation of HERV-H expression, the association of HERV-H with binding sites for pluripotency transcription factors, and the extremely high levels of HERV-H RNA in human ES cells suggest that HERV-H contributes to pluripotency in human cells. Proximity of HERV-H to binding sites for pluripotency transcription factors within ES cells might be due to retention of the same chromatin features that determined the site of integration of the ancestral, exogenous, gamma-retrovirus that gave rise to HERV-H in the distant past. Retention of these markers, or, alternatively, recruitment of them to the site of the established provirus, may have acted post-integration to fix the provirus within the germ-line of the host species. Either way, HERV-H RNA provides a specific marker for pluripotency in human cells.
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Affiliation(s)
- Federico A Santoni
- Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland.
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22
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Mameli G, Poddighe L, Mei A, Uleri E, Sotgiu S, Serra C, Manetti R, Dolei A. Expression and activation by Epstein Barr virus of human endogenous retroviruses-W in blood cells and astrocytes: inference for multiple sclerosis. PLoS One 2012; 7:e44991. [PMID: 23028727 PMCID: PMC3459916 DOI: 10.1371/journal.pone.0044991] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 08/15/2012] [Indexed: 11/20/2022] Open
Abstract
Background Proposed co-factors triggering the pathogenesis of multiple sclerosis (MS) are the Epstein Barr virus (EBV), and the potentially neuropathogenic MSRV (MS-associated retrovirus) and syncytin-1, of the W family of human endogenous retroviruses. Methodology/Principal Findings In search of links, the expression of HERV-W/MSRV/syncytin-1, with/without exposure to EBV or to EBV glycoprotein350 (EBVgp350), was studied on peripheral blood mononuclear cells (PBMC) from healthy volunteers and MS patients, and on astrocytes, by discriminatory env-specific RT-PCR assays, and by flow cytometry. Basal expression of HERV-W/MSRV/syncytin-1 occurs in astrocytes and in monocytes, NK, and B, but not in T cells. This uneven expression is amplified in untreated MS patients, and dramatically reduced during therapy. In astrocytes, EBVgp350 stimulates the expression of HERV-W/MSRV/syncytin-1, with requirement of the NF-κB pathway. In EBVgp350-treated PBMC, MSRVenv and syncytin-1 transcription is activated in B cells and monocytes, but not in T cells, nor in the highly expressing NK cells. The latter cells, but not the T cells, are activated by proinflammatory cytokines. Conclusions/Significance In vitro EBV activates the potentially immunopathogenic and neuropathogenic HERV-W/MSRV/syncytin-1, in cells deriving from blood and brain. In vivo, pathogenic outcomes would depend on abnormal situations, as in late EBV primary infection, that is often symptomatic, or/and in the presence of particular host genetic backgrounds. In the blood, HERV-Wenv activation might induce immunopathogenic phenomena linked to its superantigenic properties. In the brain, toxic mechanisms against oligodendrocytes could be established, inducing inflammation, demyelination and axonal damage. Local stimulation by proinflammatory cytokines and other factors might activate further HERV-Ws, contributing to the neuropathogenity. In MS pathogenesis, a possible model could include EBV as initial trigger of future MS, years later, and HERV-W/MSRV/syncytin-1 as actual contributor to MS pathogenicity, in striking parallelism with disease behaviour.
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Affiliation(s)
- Giuseppe Mameli
- Department of Biomedical Sciences and Centre of Excellence for Biotechnology Development and Biodiversity Research, University of Sassari, Sassari, Italy
| | - Luciana Poddighe
- Department of Biomedical Sciences and Centre of Excellence for Biotechnology Development and Biodiversity Research, University of Sassari, Sassari, Italy
| | - Alessandra Mei
- Department of Biomedical Sciences and Centre of Excellence for Biotechnology Development and Biodiversity Research, University of Sassari, Sassari, Italy
| | - Elena Uleri
- Department of Biomedical Sciences and Centre of Excellence for Biotechnology Development and Biodiversity Research, University of Sassari, Sassari, Italy
| | - Stefano Sotgiu
- Department of Neurosciences and MIS, University of Sassari, Sassari, Italy
| | - Caterina Serra
- Department of Biomedical Sciences and Centre of Excellence for Biotechnology Development and Biodiversity Research, University of Sassari, Sassari, Italy
| | - Roberto Manetti
- Department of Clinical, Experimental and Oncological Medicine, University of Sassari, Sassari, Italy
| | - Antonina Dolei
- Department of Biomedical Sciences and Centre of Excellence for Biotechnology Development and Biodiversity Research, University of Sassari, Sassari, Italy
- * E-mail:
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Petersen T, Møller-Larsen A, Ellermann-Eriksen S, Thiel S, Christensen T. Effects of interferon-beta therapy on elements in the antiviral immune response towards the human herpesviruses EBV, HSV, and VZV, and to the human endogenous retroviruses HERV-H and HERV-W in multiple sclerosis. J Neuroimmunol 2012; 249:105-8. [PMID: 22608883 DOI: 10.1016/j.jneuroim.2012.04.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 04/23/2012] [Accepted: 04/24/2012] [Indexed: 12/22/2022]
Abstract
Effects of treatment of multiple sclerosis patients with IFN-β on elements of the antiviral immune response to herpesviruses were analysed in a longitudinal study. We found significantly increased seroreactivity to EBV EBNA-1, and to VZV, in patients who did not respond to IFN-β therapy. We found no significant changes in seroreactivity to EBV EA, or to HSV. For the same patient cohort, we have previously demonstrated significant decreases in seroreactivities to envelope antigens for the two human endogenous retroviruses HERV-H and HERV-W, closely linked to efficacy of therapy. We further searched for correlations between seroreactivities to EBV, HSV, and VZV, and levels of mannan-binding lectin (MBL), and MBL-associated serine protease 3. We found no such correlations. Our results are in accord with recent reports of increased seroreactivity to EBV EBNA-1, and to VZV in active MS, and they support that the herpesviruses EBV and VZV together with HERV-H/HERV-W and the antiviral immune response may play a role in MS development.
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Affiliation(s)
- Thor Petersen
- Department of Neurology, Aarhus University Hospital, Nørrebrogade 44, Aarhus C, Denmark
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Expression of HERV-Fc1, a human endogenous retrovirus, is increased in patients with active multiple sclerosis. J Virol 2012; 86:3713-22. [PMID: 22278236 DOI: 10.1128/jvi.06723-11] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Multiple sclerosis (MS) is considered to be an autoimmune disease with an unknown cause and with immune system dysregulation. Among environmental factors, viruses are most often connected with the etiology of MS. Human endogenous retroviruses (HERVs) constitute 5 to 8% of human genomic DNA and have been detected as transcripts and proteins in the central nervous system (CNS) and peripheral blood, frequently in the context of neuroinflammation. HERV-Fc1, which belongs to the HERV-H/F family, has received our attention largely because of the genetic association with MS. We studied the expression of a capsid (Gag) protein of HERV-H/F origin by flow cytometry in peripheral blood mononuclear cells (PBMCs) from healthy controls and from MS patients with nonactive or active disease. There was a significant increase in HERV-H/F Gag expression in CD4(+) (P < 0.001) and CD8(+) (P < 0.001) T lymphocytes and in monocytes (P = 0.0356) in PBMCs from MS patients with active disease. Furthermore, we have undertaken the first rigorous SYBR green-based absolute quantitative PCR (Q-PCR) evaluation approach to quantify extracellular HERV-Fc1 RNA viral loads in plasma from MS patients and healthy controls. We found a 4-fold increase in extracellular HERV-Fc1 RNA titers in patients with active MS compared with healthy controls (P < 0.001). These findings strengthen the link between HERV-Fc1 and the pathology of MS. The cause and biological consequences of these differential expression levels will be the subject of further investigation. HERV-Fc1 biology could be a compelling area for understanding the pathology of MS and possibly other autoimmune disorders.
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25
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Autoimmune disease: A role for new anti-viral therapies? Autoimmun Rev 2011; 11:88-97. [DOI: 10.1016/j.autrev.2011.08.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2011] [Accepted: 08/11/2011] [Indexed: 12/30/2022]
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26
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Kwok JY, Vaida F, Augst RM, Yu DY, Singh KK. Mannose binding lectin mediated complement pathway in multiple sclerosis. J Neuroimmunol 2011; 239:98-100. [PMID: 21911261 DOI: 10.1016/j.jneuroim.2011.08.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 08/24/2011] [Accepted: 08/24/2011] [Indexed: 10/17/2022]
Abstract
Role of mannose binding lectin (MBL) complement activation pathway, an arm of innate immunity in multiple sclerosis (MS) was evaluated by analyzing the expression of MBL, MBL-associated serine protease-2 (MASP-2), and functional MBL/MASP-2 mediated C4 cleavage (fMBL) in 87 plasma and cerebrospinal fluid (CSF) samples from MS patients and non-MS controls. Median fMBL and MASP-2 plasma levels were higher in MS vs. non-MS cases. These associations remained in an analysis of subtypes of MS disease. These findings suggest a potential activation of MBL complement pathway in MS that may possibly alter the risk or progression of MS disease.
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Affiliation(s)
- Janet Y Kwok
- Department of Pediatrics, University of California-San Diego, La Jolla, CA 92093, United States
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27
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Pro-inflammatory cytokine and chemokine mRNA blood level in multiple sclerosis is related to treatment response and interferon-beta dose. J Neuroimmunol 2010; 226:150-7. [DOI: 10.1016/j.jneuroim.2010.05.038] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 05/14/2010] [Accepted: 05/18/2010] [Indexed: 01/28/2023]
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Abstract
In humans, exogenous retroviruses are known to cause immunodeficiency and neurological disease. While endogenous retroviruses are firmly established pathogens in other species, the human endogenous retroviruses (HERVs) may well be considered as emerging pathogens. HERVs also exhibit complex interactions with exogenous retroviruses and herpesviruses. Two neurological disorders in particular are associated with HERVs: multiple sclerosis (MS) and schizophrenia. HERV-H/F and HERV-W are specifically activated both in the circulation and the central nervous system (CNS) in a majority of MS patients, and particularly, the envelopes (env transcription and Env proteins) appear strongly associated with disease activity. Interferon beta (IFN-beta) therapy is well-established for MS. IFN-beta is also known to have anti-retroviral activities toward exogenous retroviruses (HIV and HTLV-I). New reports show that IFN-beta also mediate down-regulation of HERV-H/F and HERV-W in MS patients. HERV-W and HERV-K transcription (gag and pol) appears, to some extent, to be up-regulated in the circulation and the CNS of patients with schizophrenia. The expression of anti-HERV-W Gag reactive epitopes is reported to be down-regulated in the brain but up-regulated in the blood from schizophrenia patients. The pathogenic potential of HERVs certainly merits further studies.
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