1
|
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] [MESH Headings] [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.
Collapse
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.
| |
Collapse
|
2
|
Frau J, Coghe G, Lorefice L, Fenu G, Cocco E. The Role of Microorganisms in the Etiopathogenesis of Demyelinating Diseases. Life (Basel) 2023; 13:1309. [PMID: 37374092 DOI: 10.3390/life13061309] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 05/28/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
Multiple sclerosis (MS), neuromyelitis optica (NMO) and myelin oligodendrocyte glycoprotein antibody disease (MOGAD) are inflammatory diseases of the central nervous system (CNS) with a multifactorial aetiology. Environmental factors are important for their development and microorganisms could play a determining role. They can directly damage the CNS, but their interaction with the immune system is even more important. The possible mechanisms involved include molecular mimicry, epitope spreading, bystander activation and the dual cell receptor theory. The role of Epstein-Barr virus (EBV) in MS has been definitely established, since being seropositive is a necessary condition for the onset of MS. EBV interacts with genetic and environmental factors, such as low levels of vitamin D and human endogenous retrovirus (HERV), another microorganism implicated in the disease. Many cases of onset or exacerbation of neuromyelitis optica spectrum disorder (NMOSD) have been described after infection with Mycobacterium tuberculosis, EBV and human immunodeficiency virus; however, no definite association with a virus has been found. A possible role has been suggested for Helicobacter pylori, in particular in individuals with aquaporin 4 antibodies. The onset of MOGAD could occur after an infection, mainly in the monophasic course of the disease. A role for the HERV in MOGAD has been hypothesized. In this review, we examined the current understanding of the involvement of infectious factors in MS, NMO and MOGAD. Our objective was to elucidate the roles of each microorganism in initiating the diseases and influencing their clinical progression. We aimed to discuss both the infectious factors that have a well-established role and those that have yielded conflicting results across various studies.
Collapse
Affiliation(s)
- Jessica Frau
- Multiple Sclerosis Centre, ASL Cagliari, 09126 Cagliari, Italy
| | - Giancarlo Coghe
- Multiple Sclerosis Centre, ASL Cagliari, 09126 Cagliari, Italy
| | - Lorena Lorefice
- Multiple Sclerosis Centre, ASL Cagliari, 09126 Cagliari, Italy
| | | | - Eleonora Cocco
- Multiple Sclerosis Centre, ASL Cagliari, 09126 Cagliari, Italy
- Department of Medical Sciences and Public Health, University of Cagliari, 09124 Cagliari, Italy
| |
Collapse
|
3
|
Bjørklund G, Zou L, Peana M, Chasapis CT, Hangan T, Lu J, Maes M. The Role of the Thioredoxin System in Brain Diseases. Antioxidants (Basel) 2022; 11:2161. [PMID: 36358532 PMCID: PMC9686621 DOI: 10.3390/antiox11112161] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/23/2022] [Accepted: 10/28/2022] [Indexed: 08/08/2023] Open
Abstract
The thioredoxin system, consisting of thioredoxin (Trx), thioredoxin reductase (TrxR), and NADPH, plays a fundamental role in the control of antioxidant defenses, cell proliferation, redox states, and apoptosis. Aberrations in the Trx system may lead to increased oxidative stress toxicity and neurodegenerative processes. This study reviews the role of the Trx system in the pathophysiology and treatment of Alzheimer's, Parkinson's and Huntington's diseases, brain stroke, and multiple sclerosis. Trx system plays an important role in the pathophysiology of those disorders via multiple interactions through oxidative stress, apoptotic, neuro-immune, and pro-survival pathways. Multiple aberrations in Trx and TrxR systems related to other redox systems and their multiple reciprocal relationships with the neurodegenerative, neuro-inflammatory, and neuro-oxidative pathways are here analyzed. Genetic and environmental factors (nutrition, metals, and toxins) may impact the function of the Trx system, thereby contributing to neuropsychiatric disease. Aberrations in the Trx and TrxR systems could be a promising drug target to prevent and treat neurodegenerative, neuro-inflammatory, neuro-oxidative stress processes, and related brain disorders.
Collapse
Affiliation(s)
- Geir Bjørklund
- Council for Nutritional and Environmental Medicine, Toften 24, 8610 Mo i Rana, Norway
| | - Lili Zou
- Hubei Key Laboratory of Tumor Microenvironment and Immunotherapy, College of Basic Medical Sciences, China Three Gorges University, Yichang 443002, China
| | - Massimiliano Peana
- Department of Chemical, Physical, Mathematical and Natural Sciences, University of Sassari, Via Vienna 2, 07100 Sassari, Italy
| | - Christos T. Chasapis
- Institute of Chemical Biology, National Hellenic Research Foundation, 11635 Athens, Greece
| | - Tony Hangan
- Faculty of Medicine, Ovidius University of Constanta, 900470 Constanta, Romania
| | - Jun Lu
- School of Pharmaceutical Sciences, Southwest University, Chongqing 400715, China
| | - Michael Maes
- Department of Psychiatry, Faculty of Medicine, Chulalongkorn University, Pathumwan, Bangkok 10330, Thailand
| |
Collapse
|
4
|
Meta-Analysis Suggests That Intron Retention Can Affect Quantification of Transposable Elements from RNA-Seq Data. BIOLOGY 2022; 11:biology11060826. [PMID: 35741347 PMCID: PMC9220773 DOI: 10.3390/biology11060826] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/20/2022] [Accepted: 05/26/2022] [Indexed: 02/08/2023]
Abstract
Simple Summary Transposable elements (TEs) are repetitive sequences comprising more than one third of the human genome with the original ability to change their location within the genome. Owing to their repetitive nature, the quantification of TEs results often challenging. RNA-seq is a useful tool for genome-wide TEs quantification, nevertheless it also presents technical issues, including low reads mappability and erroneous quantification derived from the transcription of TEs fragments embedded in canonical transcripts. Fragments derived from TEs are found within the introns of most genes, which led to the hypothesis that intron retention (IR) can affect the unbiased quantification of TEs expression. Performing meta-analysis of public RNA-seq datasets, here we observe that IR can indeed impact the quantification of TEs by increasing the number of reads mapped on intronic TE copies. Our work highlights a correlation between IR and TEs expression measurement by RNA-seq that should be taken into account to achieve reliable TEs quantification, especially in samples characterized by extensive IR, because differential IR might be confused with differential TEs expression. Abstract Transposable elements (TEs), also known as “jumping genes”, are repetitive sequences with the capability of changing their location within the genome. They are key players in many different biological processes in health and disease. Therefore, a reliable quantification of their expression as transcriptional units is crucial to distinguish between their independent expression and the transcription of their sequences as part of canonical transcripts. TEs quantification faces difficulties of different types, the most important one being low reads mappability due to their repetitive nature preventing an unambiguous mapping of reads originating from their sequences. A large fraction of TEs fragments localizes within introns, which led to the hypothesis that intron retention (IR) can be an additional source of bias, potentially affecting accurate TEs quantification. IR occurs when introns, normally removed from the mature transcript by the splicing machinery, are maintained in mature transcripts. IR is a widespread mechanism affecting many different genes with cell type-specific patterns. We hypothesized that, in an RNA-seq experiment, reads derived from retained introns can introduce a bias in the detection of overlapping, independent TEs RNA expression. In this study we performed meta-analysis using public RNA-seq data from lymphoblastoid cell lines and show that IR can impact TEs quantification using established tools with default parameters. Reads mapped on intronic TEs were indeed associated to the expression of TEs and influence their correct quantification as independent transcriptional units. We confirmed these results using additional independent datasets, demonstrating that this bias does not appear in samples where IR is not present and that differential TEs expression does not impact on IR quantification. We concluded that IR causes the over-quantification of intronic TEs and differential IR might be confused with differential TEs expression. Our results should be taken into account for a correct quantification of TEs expression from RNA-seq data, especially in samples in which IR is abundant.
Collapse
|
5
|
Chesnokova E, Beletskiy A, Kolosov P. The Role of Transposable Elements of the Human Genome in Neuronal Function and Pathology. Int J Mol Sci 2022; 23:5847. [PMID: 35628657 PMCID: PMC9148063 DOI: 10.3390/ijms23105847] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 05/17/2022] [Accepted: 05/19/2022] [Indexed: 12/13/2022] Open
Abstract
Transposable elements (TEs) have been extensively studied for decades. In recent years, the introduction of whole-genome and whole-transcriptome approaches, as well as single-cell resolution techniques, provided a breakthrough that uncovered TE involvement in host gene expression regulation underlying multiple normal and pathological processes. Of particular interest is increased TE activity in neuronal tissue, and specifically in the hippocampus, that was repeatedly demonstrated in multiple experiments. On the other hand, numerous neuropathologies are associated with TE dysregulation. Here, we provide a comprehensive review of literature about the role of TEs in neurons published over the last three decades. The first chapter of the present review describes known mechanisms of TE interaction with host genomes in general, with the focus on mammalian and human TEs; the second chapter provides examples of TE exaptation in normal neuronal tissue, including TE involvement in neuronal differentiation and plasticity; and the last chapter lists TE-related neuropathologies. We sought to provide specific molecular mechanisms of TE involvement in neuron-specific processes whenever possible; however, in many cases, only phenomenological reports were available. This underscores the importance of further studies in this area.
Collapse
Affiliation(s)
- Ekaterina Chesnokova
- Laboratory of Cellular Neurobiology of Learning, Institute of Higher Nervous Activity and Neurophysiology of the Russian Academy of Sciences, 117485 Moscow, Russia; (A.B.); (P.K.)
| | | | | |
Collapse
|
6
|
Viral Proteins with PxxP and PY Motifs May Play a Role in Multiple Sclerosis. Viruses 2022; 14:v14020281. [PMID: 35215874 PMCID: PMC8879583 DOI: 10.3390/v14020281] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/19/2022] [Accepted: 01/26/2022] [Indexed: 02/04/2023] Open
Abstract
Multiple sclerosis (MS) is a debilitating disease that arises from immune system attacks to the protective myelin sheath that covers nerve fibers and ensures optimal communication between brain and body. Although the cause of MS is unknown, a number of factors, which include viruses, have been identified as increasing the risk of displaying MS symptoms. Specifically, the ubiquitous and highly prevalent Epstein–Barr virus, human herpesvirus 6, cytomegalovirus, varicella–zoster virus, and other viruses have been identified as potential triggering agents. In this review, we examine the specific role of proline-rich proteins encoded by these viruses and their potential role in MS at a molecular level.
Collapse
|
7
|
Meier UC, Cipian RC, Karimi A, Ramasamy R, Middeldorp JM. Cumulative Roles for Epstein-Barr Virus, Human Endogenous Retroviruses, and Human Herpes Virus-6 in Driving an Inflammatory Cascade Underlying MS Pathogenesis. Front Immunol 2021; 12:757302. [PMID: 34790199 PMCID: PMC8592026 DOI: 10.3389/fimmu.2021.757302] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/11/2021] [Indexed: 12/12/2022] Open
Abstract
Roles for viral infections and aberrant immune responses in driving localized neuroinflammation and neurodegeneration in multiple sclerosis (MS) are the focus of intense research. Epstein-Barr virus (EBV), as a persistent and frequently reactivating virus with major immunogenic influences and a near 100% epidemiological association with MS, is considered to play a leading role in MS pathogenesis, triggering localized inflammation near or within the central nervous system (CNS). This triggering may occur directly via viral products (RNA and protein) and/or indirectly via antigenic mimicry involving B-cells, T-cells and cytokine-activated astrocytes and microglia cells damaging the myelin sheath of neurons. The genetic MS-risk factor HLA-DR2b (DRB1*1501β, DRA1*0101α) may contribute to aberrant EBV antigen-presentation and anti-EBV reactivity but also to mimicry-induced autoimmune responses characteristic of MS. A central role is proposed for inflammatory EBER1, EBV-miRNA and LMP1 containing exosomes secreted by viable reactivating EBV+ B-cells and repetitive release of EBNA1-DNA complexes from apoptotic EBV+ B-cells, forming reactive immune complexes with EBNA1-IgG and complement. This may be accompanied by cytokine- or EBV-induced expression of human endogenous retrovirus-W/-K (HERV-W/-K) elements and possibly by activation of human herpesvirus-6A (HHV-6A) in early-stage CNS lesions, each contributing to an inflammatory cascade causing the relapsing-remitting neuro-inflammatory and/or progressive features characteristic of MS. Elimination of EBV-carrying B-cells by antibody- and EBV-specific T-cell therapy may hold the promise of reducing EBV activity in the CNS, thereby limiting CNS inflammation, MS symptoms and possibly reversing disease. Other approaches targeting HHV-6 and HERV-W and limiting inflammatory kinase-signaling to treat MS are also being tested with promising results. This article presents an overview of the evidence that EBV, HHV-6, and HERV-W may have a pathogenic role in initiating and promoting MS and possible approaches to mitigate development of the disease.
Collapse
Affiliation(s)
- Ute-Christiane Meier
- Institut für Laboratoriumsmedizin, Klinikum der Universität München, München, Germany.,Department of Psychological Medicine, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, United Kingdom
| | | | - Abbas Karimi
- Department of Molecular Medicine, Faculty of Advanced Medical Sciences, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | | |
Collapse
|
8
|
Pandit L, Malli C, D'Cunha A, Sudhir A. Role of Viral Infections in Multiple Sclerosis Pathogenesis among Indian Population. Neurol India 2021; 69:681-685. [PMID: 34169868 DOI: 10.4103/0028-3886.319209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Background The role of viral infections in multiple sclerosis (MS) pathogenesis is unclear. Objective Certain neurotropic viruses previously linked with MS among white population were studied including Epstein-Barr virus, human herpesvirus-6 (HHV-6) and MS-associated retrovirus (MSRV). Material and Methods Sixty-two MS patients (37 had a recent clinical relapse) and 65 controls with other neurological disorders were included. Blood and cerebrospinal fluid (CSF) samples were obtained and processed with the primary objective of determining whether there was intrathecal multiplication of viruses under study (EBV, HHV6 A and B and human endogenous retrovirus) or a breach in blood-brain barrier associated with viral presence in both peripheral blood and CSF. Results Evidence of breach in blood-brain barrier was seen in 86.5% of patients as evidenced by abnormal CSF/serum albumin index and or MRI. EBV nuclear antigen (EBNA1 IgG) was seen in 89% of MS patients and 58% controls (P = <0.001). However, HHV6 IgG was similar in both groups (85% versus 81%; P = 0.45). In affinity immunoblotting reaction intrathecal IgG synthesis against EBNA1 antigen was demonstrable in 26% (16/62) of patients and none against HHV6. A subset of patients showed significant elevation in mean copy number of plasma EBV DNA during relapse and there was a trend for the same among patients harboring HHV-6B. No evidence of isolated intrathecal viral presence or multiplication was seen. Conclusions The results of our study suggest that viruses studied namely EBV and HHV6 have a role in triggering relapses through a peripheral mechanism, rather than a direct role through intrathecal multiplication.
Collapse
Affiliation(s)
- Lekha Pandit
- Center for Advanced Neurological Research, K S Hegde Medical Academy, Nitte, (Deemed to be University), Mangalore, Karnataka, India
| | - Chaithra Malli
- Center for Advanced Neurological Research, K S Hegde Medical Academy, Nitte, (Deemed to be University), Mangalore, Karnataka, India
| | - Anitha D'Cunha
- Center for Advanced Neurological Research, K S Hegde Medical Academy, Nitte, (Deemed to be University), Mangalore, Karnataka, India
| | - Akshatha Sudhir
- Center for Advanced Neurological Research, K S Hegde Medical Academy, Nitte, (Deemed to be University), Mangalore, Karnataka, India
| |
Collapse
|
9
|
Jakhmola S, Upadhyay A, Jain K, Mishra A, Jha HC. Herpesviruses and the hidden links to Multiple Sclerosis neuropathology. J Neuroimmunol 2021; 358:577636. [PMID: 34174587 DOI: 10.1016/j.jneuroim.2021.577636] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 06/01/2021] [Accepted: 06/17/2021] [Indexed: 01/08/2023]
Abstract
Herpesviruses like Epstein-Barr virus, human herpesvirus (HHV)-6, HHV-1, VZV, and human endogenous retroviruses, have an age-old clinical association with multiple sclerosis (MS). MS is an autoimmune disease of the nervous system wherein the myelin sheath deteriorates. The most popular mode of virus mediated immune system manipulation is molecular mimicry. Numerous herpesvirus antigens are similar to myelin proteins. Other mechanisms described here include the activity of cytokines and autoantibodies produced by the autoreactive T and B cells, respectively, viral déjà vu, epitope spreading, CD46 receptor engagement, impaired remyelination etc. Overall, this review addresses the host-parasite association of viruses with MS.
Collapse
Affiliation(s)
- Shweta Jakhmola
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India
| | - Arun Upadhyay
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology, Jodhpur, India
| | - Khushboo Jain
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India
| | - Amit Mishra
- Cellular and Molecular Neurobiology Unit, Indian Institute of Technology, Jodhpur, India
| | - Hem Chandra Jha
- Infection Bioengineering Group, Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, India.
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Keegan RM, Talbot LR, Chang YH, Metzger MJ, Dubnau J. Intercellular viral spread and intracellular transposition of Drosophila gypsy. PLoS Genet 2021; 17:e1009535. [PMID: 33886543 PMCID: PMC8096092 DOI: 10.1371/journal.pgen.1009535] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 05/04/2021] [Accepted: 04/06/2021] [Indexed: 01/12/2023] Open
Abstract
It has become increasingly clear that retrotransposons (RTEs) are more widely expressed in somatic tissues than previously appreciated. RTE expression has been implicated in a myriad of biological processes ranging from normal development and aging, to age related diseases such as cancer and neurodegeneration. Long Terminal Repeat (LTR)-RTEs are evolutionary ancestors to, and share many features with, exogenous retroviruses. In fact, many organisms contain endogenous retroviruses (ERVs) derived from exogenous retroviruses that integrated into the germ line. These ERVs are inherited in Mendelian fashion like RTEs, and some retain the ability to transmit between cells like viruses, while others develop the ability to act as RTEs. The process of evolutionary transition between LTR-RTE and retroviruses is thought to involve multiple steps by which the element loses or gains the ability to transmit copies between cells versus the ability to replicate intracellularly. But, typically, these two modes of transmission are incompatible because they require assembly in different sub-cellular compartments. Like murine IAP/IAP-E elements, the gypsy family of retroelements in arthropods appear to sit along this evolutionary transition. Indeed, there is some evidence that gypsy may exhibit retroviral properties. Given that gypsy elements have been found to actively mobilize in neurons and glial cells during normal aging and in models of neurodegeneration, this raises the question of whether gypsy replication in somatic cells occurs via intracellular retrotransposition, intercellular viral spread, or some combination of the two. These modes of replication in somatic tissues would have quite different biological implications. Here, we demonstrate that Drosophila gypsy is capable of both cell-associated and cell-free viral transmission between cultured S2 cells of somatic origin. Further, we demonstrate that the ability of gypsy to move between cells is dependent upon a functional copy of its viral envelope protein. This argues that the gypsy element has transitioned from an RTE into a functional endogenous retrovirus with the acquisition of its envelope gene. On the other hand, we also find that intracellular retrotransposition of the same genomic copy of gypsy can occur in the absence of the Env protein. Thus, gypsy exhibits both intracellular retrotransposition and intercellular viral transmission as modes of replicating its genome.
Collapse
Affiliation(s)
- Richard M. Keegan
- Program in Neuroscience, Department of Neurobiology and Behavior, Stony Brook University, New York City, New York, United States of America
| | - Lillian R. Talbot
- Medical Scientist Training Program, Department of Neurobiology and Behavior, Stony Brook University, New York City, New York, United States of America
| | - Yung-Heng Chang
- Department of Anesthesiology, Stony Brook School of Medicine, New York City, New York, United States of America
| | - Michael J. Metzger
- Pacific Northwest Research Institute, Seattle, Washington, United States of America
| | - Josh Dubnau
- Program in Neuroscience, Department of Neurobiology and Behavior, Stony Brook University, New York City, New York, United States of America
- Department of Anesthesiology, Stony Brook School of Medicine, New York City, New York, United States of America
- Pacific Northwest Research Institute, Seattle, Washington, United States of America
| |
Collapse
|
12
|
Ahmadi A, De Toma I, Vilor-Tejedor N, Eftekhariyan Ghamsari MR, Sadeghi I. Transposable elements in brain health and disease. Ageing Res Rev 2020; 64:101153. [PMID: 32977057 DOI: 10.1016/j.arr.2020.101153] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 07/22/2020] [Accepted: 08/19/2020] [Indexed: 12/17/2022]
Abstract
Transposable elements (TEs) occupy a large fraction of the human genome but only a small proportion of these elements are still active today. Recent works have suggested that TEs are expressed and active in the brain, challenging the dogma that neuronal genomes are static and revealing that they are susceptible to somatic genomic alterations. These new findings have major implications for understanding the neuroplasticity of the brain, which could hypothetically have a role in behavior and cognition, and contribute to vulnerability to disease. As active TEs could induce genetic diversity and mutagenesis, their influences on human brain development and diseases are of great interest. In this review, we will focus on the active TEs in the human genome and discuss in detail their impacts on human brain development. Furthermore, the association between TEs and brain-related diseases is discussed.
Collapse
|
13
|
Evans TA, Erwin JA. Retroelement-derived RNA and its role in the brain. Semin Cell Dev Biol 2020; 114:68-80. [PMID: 33229216 DOI: 10.1016/j.semcdb.2020.11.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 10/20/2020] [Accepted: 11/04/2020] [Indexed: 12/17/2022]
Abstract
Comprising ~40% of the human genome, retroelements are mobile genetic elements which are transcribed into RNA, then reverse-transcribed into DNA and inserted into a new site in the genome. Retroelements are referred to as "genetic parasites", residing among host genes and relying on host machinery for transcription and evolutionary propagation. The healthy brain has the highest expression of retroelement-derived sequences compared to other somatic tissue, which leads to the question: how does retroelement-derived RNA influence human traits and cellular states? While the functional importance of upregulating retroelement expression in the brain is an active area of research, RNA species derived from retroelements influence both self- and host gene expression by contributing to chromatin remodeling, alternative splicing, somatic mosaicism and translational repression. Here, we review the emerging evidence that the functional importance of RNA derived from retroelements is multifaceted. Retroelements can influence organismal states through the seeding of epigenetic states in chromatin, the production of structured RNA and even catalytically active ribozymes, the generation of cytoplasmic ssDNA and RNA/DNA hybrids, the production of viral-like proteins, and the generation of somatic mutations. Comparative sequencing suggests that retroelements can contribute to intraspecies variation through these mechanisms to alter transcript identity and abundance. In humans, an increasing number of neurodevelopmental and neurodegenerative conditions are associated with dysregulated retroelements, including Aicardi-Goutieres syndrome (AGS), Rett syndrome (RTT), Amyotrophic Lateral Sclerosis (ALS), Alzheimer's disease (AD), multiple sclerosis (MS), schizophrenia (SZ), and aging. Taken together, these concepts suggest a larger functional role for RNA derived from retroelements. This review aims to define retroelement-derived RNA, discuss how it impacts the mammalian genome, as well as summarize data supporting phenotypic consequences of this unique RNA subset in the brain.
Collapse
Affiliation(s)
- Taylor A Evans
- Lieber Institute for Brain Development, Baltimore, MD, USA; Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jennifer Ann Erwin
- Lieber Institute for Brain Development, Baltimore, MD, USA; Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA; Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
14
|
Abstract
The etiology and pathogenesis of MS is likely to involve multiple factors interacting with each other, and the role of infectious and viral agents is still under debate, however a consistent amount of studies suggests that some viruses are associated with the disease. The strongest documentation has come from the detection of viral nucleic acid or antigen or of an anti-viral antibody response in MS patients. A further step for the study of the mechanism viruses might be involved in can be made using in vitro and in vivo models. While in vitro models, based on glial and neural cell lines from various sources are widely used, in vivo animal models present challenges. Indeed neurotropic animal viruses are currently used to study demyelination in well-established models, but animal models of demyelination by human virus infection have only recently been developed, using animal gammaherpesviruses closely related to Epstein Barr virus (EBV), or using marmosets expressing the specific viral receptor for Human Herpesvirus 6 (HHV-6). The present review will illustrate the main potential mechanisms of MS pathogenesis possibly associated with viral infections and viruses currently used to study demyelination in animal models. Then the viruses most strongly linked with MS will be discussed, in the perspective that more than one virus might have a role, with varying degrees of interaction, contributing to MS heterogeneity.
Collapse
Affiliation(s)
- Donatella Donati
- Neurologia e Neurofisiologia Clinica, Azienda Ospedaliera Universitaria Senese I 53100 Siena, Italy
| |
Collapse
|
15
|
Saleh A, Macia A, Muotri AR. Transposable Elements, Inflammation, and Neurological Disease. Front Neurol 2019; 10:894. [PMID: 31481926 PMCID: PMC6710400 DOI: 10.3389/fneur.2019.00894] [Citation(s) in RCA: 87] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 08/02/2019] [Indexed: 12/13/2022] Open
Abstract
Transposable Elements (TE) are mobile DNA elements that can replicate and insert themselves into different locations within the host genome. Their propensity to self-propagate has a myriad of consequences and yet their biological significance is not well-understood. Indeed, retrotransposons have evaded evolutionary attempts at repression and may contribute to somatic mosaicism. Retrotransposons are emerging as potent regulatory elements within the human genome. In the diseased state, there is mounting evidence that endogenous retroelements play a role in etiopathogenesis of inflammatory diseases, with a disposition for both autoimmune and neurological disorders. We postulate that active mobile genetic elements contribute more to human disease pathogenesis than previously thought.
Collapse
Affiliation(s)
- Aurian Saleh
- Department of Pediatrics, Rady Children's Hospital San Diego, University of California, San Diego, San Diego, CA, United States
| | - Angela Macia
- Department of Pediatrics, Rady Children's Hospital San Diego, University of California, San Diego, San Diego, CA, United States
| | - Alysson R Muotri
- Department of Pediatrics, Rady Children's Hospital San Diego, University of California, San Diego, San Diego, CA, United States
| |
Collapse
|
16
|
pHERV-W envelope protein fuels microglial cell-dependent damage of myelinated axons in multiple sclerosis. Proc Natl Acad Sci U S A 2019; 116:15216-15225. [PMID: 31213545 DOI: 10.1073/pnas.1901283116] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Axonal degeneration is central to clinical disability and disease progression in multiple sclerosis (MS). Myeloid cells such as brain-resident microglia and blood-borne monocytes are thought to be critically involved in this degenerative process. However, the exact underlying mechanisms have still not been clarified. We have previously demonstrated that human endogenous retrovirus type W (HERV-W) negatively affects oligodendroglial precursor cell (OPC) differentiation and remyelination via its envelope protein pathogenic HERV-W (pHERV-W) ENV (formerly MS-associated retrovirus [MSRV]-ENV). In this current study, we investigated whether pHERV-W ENV also plays a role in axonal injury in MS. We found that in MS lesions, pHERV-W ENV is present in myeloid cells associated with axons. Focusing on progressive disease stages, we could then demonstrate that pHERV-W ENV induces a degenerative phenotype in microglial cells, driving them toward a close spatial association with myelinated axons. Moreover, in pHERV-W ENV-stimulated myelinated cocultures, microglia were found to structurally damage myelinated axons. Taken together, our data suggest that pHERV-W ENV-mediated microglial polarization contributes to neurodegeneration in MS. Thus, this analysis provides a neurobiological rationale for a recently completed clinical study in MS patients showing that antibody-mediated neutralization of pHERV-W ENV exerts neuroprotective effects.
Collapse
|
17
|
Curtin F, Bernard C, Levet S, Perron H, Porchet H, Médina J, Malpass S, Lloyd D, Simpson R. A new therapeutic approach for type 1 diabetes: Rationale for GNbAC1, an anti-HERV-W-Env monoclonal antibody. Diabetes Obes Metab 2018; 20:2075-2084. [PMID: 29749030 DOI: 10.1111/dom.13357] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/08/2018] [Accepted: 05/09/2018] [Indexed: 12/22/2022]
Abstract
We describe a newly identified therapeutic target for type 1 diabetes (T1D): an envelope protein of endogenous retroviral origin, human endogenous retrovirus W envelope (HERV-W-Env). HERV-W-Env was found to be detected in the blood of ~60% of patients with T1D and is expressed in acinar pancreatic cells of 75% of patients with T1D at post mortem examination. Preclinical experiments showed that this protein displays direct cytotoxicity on human β-islet cells. In vivo HERV-W-Env impairs the insulin and glucose metabolism in transgenic mice expressing HERV-W-Env. GNbAC1, an IgG4 monoclonal antibody, has been developed to specifically target HERV-W-Env and to neutralize the effect of HERV-W-Env in vitro and in vivo. GNbAC1 is currently in clinical development for multiple sclerosis and > 300 subjects have been administered with GNbAC1 so far. GNbAC1 is now being tested in T1D in the RAINBOW-T1D study, which is a randomized placebo-controlled study with the objective of showing the safety and pharmacodynamic response of GNbAC1 in patients who have had T1D with a maximum of 4 years' duration. GNbAC1 is being tested vs placebo at the dose of 6 mg/kg in 60 patients during six repeated administrations for 6 months; a 6-month open-label extension will follow. The primary endpoint is to assess safety, and secondary endpoints are the pharmacodynamic responses to GNbAC1. GNbAC1 targeting HERV-W-Env is currently in clinical development in T1D, with the first safety and pharmacodynamic study. If the study results are positive, this may open the door to the development of an innovative non-immunomodulatory disease-modifying treatment for T1D.
Collapse
Affiliation(s)
- Francois Curtin
- GeNeuro SA, Plan-les-Ouates, Switzerland
- Division of Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | | | | | - Hervé Perron
- GeNeuro SA, Plan-les-Ouates, Switzerland
- Geneuro-Innovation, Lyon, France
- Laboratory of Immune Deficiencies, Faculty of Medicine Laënnec, University of Lyon, Lyon, France
| | - Hervé Porchet
- GeNeuro SA, Plan-les-Ouates, Switzerland
- Department of Pharmacology, University of Pretoria, Pretoria, South Africa
| | | | - Sam Malpass
- Southern Star Research Pty Ltd, Gordon, Australia
| | - David Lloyd
- Southern Star Research Pty Ltd, Gordon, Australia
| | | |
Collapse
|
18
|
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.
Collapse
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
| |
Collapse
|
19
|
Abstract
PURPOSE OF REVIEW Following the establishment of a number of successful immunomodulatory treatments for multiple sclerosis, current research focuses on the repair of existing damage. RECENT FINDINGS Promotion of regeneration is particularly important for demyelinated areas with degenerated or functionally impaired axons of the central nervous system's white and gray matter. As the protection and generation of new oligodendrocytes is a key to the re-establishment of functional connections, adult oligodendrogenesis and myelin reconstitution processes are of primary interest. Moreover, understanding, supporting and promoting endogenous repair activities such as mediated by resident oligodendroglial precursor or adult neural stem cells are currently thought to be a promising approach toward the development of novel regenerative therapies. SUMMARY This review summarizes recent developments and findings related to pharmacological myelin repair as well as to the modulation/application of stem cells with the aim to restore defective myelin sheaths.
Collapse
|
20
|
Saito T, Miyagawa K, Chen SY, Tamosiuniene R, Wang L, Sharpe O, Samayoa E, Harada D, Moonen JRAJ, Cao A, Chen PI, Hennigs JK, Gu M, Li CG, Leib RD, Li D, Adams CM, Del Rosario PA, Bill M, Haddad F, Montoya JG, Robinson WH, Fantl WJ, Nolan GP, Zamanian RT, Nicolls MR, Chiu CY, Ariza ME, Rabinovitch M. Upregulation of Human Endogenous Retrovirus-K Is Linked to Immunity and Inflammation in Pulmonary Arterial Hypertension. Circulation 2017; 136:1920-1935. [PMID: 28935667 DOI: 10.1161/circulationaha.117.027589] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 08/31/2017] [Indexed: 02/06/2023]
Abstract
BACKGROUND Immune dysregulation has been linked to occlusive vascular remodeling in pulmonary arterial hypertension (PAH) that is hereditary, idiopathic, or associated with other conditions. Circulating autoantibodies, lung perivascular lymphoid tissue, and elevated cytokines have been related to PAH pathogenesis but without a clear understanding of how these abnormalities are initiated, perpetuated, and connected in the progression of disease. We therefore set out to identify specific target antigens in PAH lung immune complexes as a starting point toward resolving these issues to better inform future application of immunomodulatory therapies. METHODS Lung immune complexes were isolated and PAH target antigens were identified by liquid chromatography tandem mass spectrometry, confirmed by enzyme-linked immunosorbent assay, and localized by confocal microscopy. One PAH antigen linked to immunity and inflammation was pursued and a link to PAH pathophysiology was investigated by next-generation sequencing, functional studies in cultured monocytes and endothelial cells, and hemodynamic and lung studies in a rat. RESULTS SAM domain and HD domain-containing protein 1 (SAMHD1), an innate immune factor that suppresses HIV replication, was identified and confirmed as highly expressed in immune complexes from 16 hereditary and idiopathic PAH versus 12 control lungs. Elevated SAMHD1 was localized to endothelial cells, perivascular dendritic cells, and macrophages, and SAMHD1 antibodies were prevalent in tertiary lymphoid tissue. An unbiased screen using metagenomic sequencing related SAMHD1 to increased expression of human endogenous retrovirus K (HERV-K) in PAH versus control lungs (n=4). HERV-K envelope and deoxyuridine triphosphate nucleotidohydrolase mRNAs were elevated in PAH versus control lungs (n=10), and proteins were localized to macrophages. HERV-K deoxyuridine triphosphate nucleotidohydrolase induced SAMHD1 and proinflammatory cytokines (eg, interleukin 6, interleukin 1β, and tumor necrosis factor α) in circulating monocytes, pulmonary arterial endothelial cells, and also activated B cells. Vulnerability of pulmonary arterial endothelial cells (PAEC) to apoptosis was increased by HERV-K deoxyuridine triphosphate nucleotidohydrolase in an interleukin 6-independent manner. Furthermore, 3 weekly injections of HERV-K deoxyuridine triphosphate nucleotidohydrolase induced hemodynamic and vascular changes of pulmonary hypertension in rats (n=8) and elevated interleukin 6. CONCLUSIONS Our study reveals that upregulation of the endogenous retrovirus HERV-K could both initiate and sustain activation of the immune system and cause vascular changes associated with PAH.
Collapse
Affiliation(s)
- Toshie Saito
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | - Kazuya Miyagawa
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | - Shih-Yu Chen
- Department of Microbiology and Immunology (S.-Y.C., W.J.F., G.P.N.).,Baxer Laboratory for Stem Cell Biology (S.-Y.C., W.J.F., G.P.N.)
| | - Rasa Tamosiuniene
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Lingli Wang
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | - Orr Sharpe
- Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Erik Samayoa
- Stanford University School of Medicine, CA. Department of Laboratory Medicine and Medicine/Infectious Diseases (E.S., C.Y.C.), and Viral Diagnostics and Discovery Center University of California, San Francisco (E.S., C.Y.C.)
| | - Daisuke Harada
- Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Jan-Renier A J Moonen
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | - Aiqin Cao
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | - Pin-I Chen
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | - Jan K Hennigs
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | - Mingxia Gu
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | - Caiyun G Li
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | | | - Dan Li
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| | | | - Patricia A Del Rosario
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Matthew Bill
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Francois Haddad
- Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Jose G Montoya
- Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - William H Robinson
- Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Wendy J Fantl
- Department of Microbiology and Immunology (S.-Y.C., W.J.F., G.P.N.).,Baxer Laboratory for Stem Cell Biology (S.-Y.C., W.J.F., G.P.N.).,Vincent Coates Foundation Mass Spectrometry Laboratory (R.D.L., C.M.A.), and Department of Obstetrics and Gynecology (W.J.F.)
| | - Garry P Nolan
- Department of Microbiology and Immunology (S.-Y.C., W.J.F., G.P.N.).,Baxer Laboratory for Stem Cell Biology (S.-Y.C., W.J.F., G.P.N.)
| | - Roham T Zamanian
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Mark R Nicolls
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.).,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Medicine (R.T., O.S., D.H., P.A.d.R., M.B., F.H., J.G.M., W.H.R., R.T.Z., M.R.N.)
| | - Charles Y Chiu
- Stanford University School of Medicine, CA. Department of Laboratory Medicine and Medicine/Infectious Diseases (E.S., C.Y.C.), and Viral Diagnostics and Discovery Center University of California, San Francisco (E.S., C.Y.C.)
| | - Maria E Ariza
- Department of Cancer Biology and Genetics, The Ohio State University Wexner Medical Center, Columbus, OH (M.E.A.)
| | - Marlene Rabinovitch
- Vera Moulton Wall Center for Pulmonary Vascular Disease (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., P.A.d.R., M.B., R.T.Z., M.R.N., M.R.), .,Cardiovascular Institute (T.S., K.M., R.T., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., F.H., R.T.Z., M.R.N., M.R.).,Department of Pediatrics (T.S., K.M., L.W., J.-R.A.J.M., A.C., P.-I.C., J.K.H., M.G., C.G.L., D.L., M.R.)
| |
Collapse
|
21
|
Bhetariya PJ, Kriesel JD, Fischer KF. Analysis of Human Endogenous Retrovirus Expression in Multiple Sclerosis Plaques. JOURNAL OF EMERGING DISEASES AND VIROLOGY 2017; 3:10.16966/2473-1846.133. [PMID: 28868516 PMCID: PMC5580941 DOI: 10.16966/2473-1846.133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND It has been suggested that Human endogenous retroviruses (HERVs) are associated with multiple sclerosis (MS) pathogenesis. The objective of this study was to broadly evaluate the expression of HERV core (GAG) and envelope (ENV) genes in diseased brain white matter samples from MS patients compared to normal controls. METHODS Twenty-eight HERV GAG and 88 ENV gene sequences were retrieved, classified by phylogeny, and grouped into clades. Consensus qPCR primers were designed for each clade, and quantitative PCR was performed on 33 MS and 9 normal control frozen brain samples. MS samples included chronic progressive (n=5), primary progressive (n=4), secondary progressive (n=14), relapsing remitting (n=3) and unclassified confirmed MS cases (n=7). The levels of GAG and ENV RNA within each of the samples were quantitated and normalized using the neuronal reference gene RPL19. Expression differences were analyzed for MS vs control. RESULTS Expression of GAG clades 1A, 3B, and 3C mapping to HERV-E and HERV-K were significantly increased compared to controls, while GAG clade 3A expression was decreased. Expression of HERV ENV clades 2, 3A, 3B, mapping to RTVL, HERV-E and HERV-K and MSRV (HERV-W), were significantly increased in the MS group. However, the relative expression differences between the MS and control groups were small, differing less than 1.5-fold. CONCLUSION Expression of GAG and ENV mapping to HERV-E, RTVL and HERV-K10 families were significantly increased in the MS group. However, the relative expression differences between the MS and control groups were small, differing less than 1.5-fold. These results indicate that the expression of HERV GAG and ENV regions do not differ greatly between MS and controls in these frozen brain samples.
Collapse
Affiliation(s)
- PJ Bhetariya
- Department of Internal Medicine, Division of Infectious Diseases, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - JD Kriesel
- Department of Internal Medicine, Division of Infectious Diseases, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - KF Fischer
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, USA
| |
Collapse
|
22
|
Kriesel JD, Bhetariya PJ, Chan BK, Wilson T, Fischer KF. Enrichment of Retroviral Sequences in Brain Tissue from Patients with Severe Demyelinating Diseases. ACTA ACUST UNITED AC 2017; 3. [PMID: 29202119 PMCID: PMC5707126 DOI: 10.16966/2473-1846.132] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Background Our group has used deep sequencing to identify viral RNA signatures in human brain specimens. We have previously used this method to detect HSV1, GBV-C, and measles virus sequence in brain tissue from deceased donors. Deep sequencing was performed on brain specimens from a cohort of patients who died with progressive forms of MS, revealing evidence of increased expression of some human endogenous retrovirus (HERV) domains. Objectives Identify RNA sequences and new antigens involved in the pathogenesis of MS Methods Deep sequencing was performed on RNA extracted from 12 progressive MS, 2 neuromyelitis optica (MS/NMO = demyelination group), 14 normal control, and 7 other neurologic disease (OND) control frozen brain specimens. The resulting single-ended 50 bp sequences (reads) were compared to a non redundant viral database representing (NRVDB) all 1.2 M viral records in GenBank. A retroviral gene catalog (RVGC) was prepared by identifying human genetic loci (GRCh37.p13) homologous to domains contained in the Gypsy 2.0 retro element database. Reads were aligned to the RVGC and human transcriptome with Bowtie2. The resulting viral hit rates (VHRs) were normalized by the number of high quality reads. The expression of human genes, including HERVs, was determined using Cufflinks. Comparisons between the groups were performed using the false discovery rate. Results Fifty to 131 million high quality reads per specimen were obtained. Comparison of the reads to the NRVDB suggested that the demyelination and OND specimens had higher VHRs against some retroviral sequences compared with the controls. This was confirmed by retroviral domain averaging. Gene expression analysis showed differential expression among some HERV sequences. Single read mapping revealed one envelope and one reverse transcriptase sequence record that were significantly enriched among the demyelination samples compared to the normal controls. Less restrictive (comprehensive) read mapping showed that 2 integrase, 2 core, 2 envelope, and 3 KRAB sequences that were overexpressed in the demyelination group. Conclusions These data demonstrate that some endogenous retroviral sequences are significantly overexpressed in these demyelination brain tissue specimens, but the magnitude of this overexpression is small. This is consistent with the concept of HERV activation as a part of the innate immune response.
Collapse
Affiliation(s)
- J D Kriesel
- Department of Internal Medicine, Division of Infectious Diseases, USA
| | - P J Bhetariya
- Department of Internal Medicine, Division of Infectious Diseases, USA
| | - B K Chan
- Yale University, Department of Ecology and Evolutionary Biology, New Haven, Connecticut, USA
| | - T Wilson
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, USA
| | - K F Fischer
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, Utah, USA
| |
Collapse
|
23
|
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.
Collapse
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.
| |
Collapse
|
24
|
Prehistoric enemies within: The contribution of human endogenous retroviruses to neurological diseases. Meeting report: "Second International Workshop on Human Endogenous Retroviruses and Disease", Washington DC, March 13th and 14th 2017. Mult Scler Relat Disord 2017. [PMID: 28641767 DOI: 10.1016/j.msard.2017.05.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Second International Workshop on Human Endogenous Retroviruses and Disease, Washington DC, March 13-14 2017 brought together international basic and clinical scientists investigating the involvement of human endogenous retroviruses (HERVs) in complex human diseases.
Collapse
|
25
|
Morandi E, Tanasescu R, Tarlinton RE, Constantinescu CS, Zhang W, Tench C, Gran B. The association between human endogenous retroviruses and multiple sclerosis: A systematic review and meta-analysis. PLoS One 2017; 12:e0172415. [PMID: 28207850 PMCID: PMC5313176 DOI: 10.1371/journal.pone.0172415] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2016] [Accepted: 02/03/2017] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The interaction between genetic and environmental factors is crucial to multiple sclerosis (MS) pathogenesis. Human Endogenous Retroviruses (HERVs) are endogenous viral elements of the human genome whose expression is associated with MS. OBJECTIVE To perform a systematic review and meta-analysis and to assess qualitative and quantitative evidence on the expression of HERV families in MS patients. METHODS Medline, Embase and the Cochrane Library were searched for published studies on the association of HERVs and MS. Meta-analysis was performed on the HERV-W family. Odds Ratio (OR) and 95% confidence interval (CI) were calculated for association. RESULTS 43 reports were extracted (25 related to HERV-W, 13 to HERV-H, 9 to HERV-K, 5 to HRES-1 and 1 to HER-15 family). The analysis showed an association between expression of all HERV families and MS. For HERV-W, adequate data was available for meta-analysis. Results from meta-analyses of HERV-W were OR = 22.66 (95%CI 6.32 to 81.20) from 4 studies investigating MSRV/HERV-W (MS-associated retrovirus) envelope mRNA in peripheral blood mononuclear cells, OR = 44.11 (95%CI 12.95 to 150.30) from 6 studies of MSRV/HERV-W polymerase mRNA in serum/plasma and OR = 6.00 (95%CI 3.35 to 10.74) from 4 studies of MSRV/HERV-W polymerase mRNA in CSF. CONCLUSIONS This systematic review and meta-analysis shows an association between expression of HERVs, and in particular the HERV-W family, and MS.
Collapse
Affiliation(s)
- Elena Morandi
- Division of Clinical Neuroscience, University of Nottingham School of Medicine, Nottingham, Nottingham, United Kingdom
| | - Radu Tanasescu
- Division of Clinical Neuroscience, University of Nottingham School of Medicine, Nottingham, Nottingham, United Kingdom
- Division of Clinical Neurosciences, University of Medicine and Pharmacy Carol Davila, Department of Neurology, Colentina Hospital, Bucharest, Romania
| | - Rachael E. Tarlinton
- University of Nottingham School of Veterinary Medicine and Science, Nottingham, United Kingdom
| | - Cris S. Constantinescu
- Division of Clinical Neuroscience, University of Nottingham School of Medicine, Nottingham, Nottingham, United Kingdom
- Department of Neurology, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom
| | - Weiya Zhang
- Division of Rheumatology, Orthopaedics and Dermatology, University of Nottingham School of Medicine, Nottingham, United Kingdom
| | - Christopher Tench
- Division of Clinical Neuroscience, University of Nottingham School of Medicine, Nottingham, Nottingham, United Kingdom
| | - Bruno Gran
- Division of Clinical Neuroscience, University of Nottingham School of Medicine, Nottingham, Nottingham, United Kingdom
- Department of Neurology, Nottingham University Hospitals NHS Trust, Nottingham, United Kingdom
| |
Collapse
|
26
|
Mortelmans K, Wang-Johanning F, Johanning GL. The role of human endogenous retroviruses in brain development and function. APMIS 2016; 124:105-15. [PMID: 26818265 DOI: 10.1111/apm.12495] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Accepted: 11/09/2015] [Indexed: 12/13/2022]
Abstract
Endogenous retroviral sequences are spread throughout the genome of all humans, and make up about 8% of the genome. Despite their prevalence, the function of human endogenous retroviruses (HERVs) in humans is largely unknown. In this review we focus on the brain, and evaluate studies in animal models that address mechanisms of endogenous retrovirus activation in the brain and central nervous system (CNS). One such study in mice found that TRIM28, a protein critical for mouse early development, regulates transcription and silencing of endogenous retroviruses in neural progenitor cells. Another intriguing finding in human brain cells and mouse models was that endogenous retrovirus HERV-K appears to be protective against neurotoxins. We also report on studies that associate HERVs with human diseases of the brain and CNS. There is little doubt of an association between HERVs and a number of CNS diseases. However, a cause and effect relationship between HERVs and these diseases has not yet been established.
Collapse
Affiliation(s)
- Kristien Mortelmans
- Discovery Biology Section, Biosciences Division, SRI International, Menlo Park, CA, USA
| | - Feng Wang-Johanning
- Discovery Biology Section, Biosciences Division, SRI International, Menlo Park, CA, USA
| | - Gary L Johanning
- Discovery Biology Section, Biosciences Division, SRI International, Menlo Park, CA, USA
| |
Collapse
|
27
|
Bollati V, Favero C, Albetti B, Tarantini L, Moroni A, Byun HM, Motta V, Conti DM, Tirelli AS, Vigna L, Bertazzi PA, Pesatori AC. Nutrients intake is associated with DNA methylation of candidate inflammatory genes in a population of obese subjects. Nutrients 2014; 6:4625-39. [PMID: 25340371 PMCID: PMC4210937 DOI: 10.3390/nu6104625] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 10/14/2014] [Accepted: 10/15/2014] [Indexed: 12/29/2022] Open
Abstract
The aim of the present study was to evaluate the potential association between dietary nutrients and alterations in DNA methylation in a set of five candidate genes, including CD14, Et-1, iNOS, HERV-w and TNFα, in a population of overweight/obese subjects. We evaluated possible associations between gene methylation and clinical blood parameters, including total cholesterol (TC), low- and high-density lipoprotein cholesterol (LDL-C and HDL-C), triglyceride and homocysteine levels. We employed validated methods to assess anthropometric, clinical and dietary data, as well as pyrosequencing to evaluate DNA methylation of the five candidate genes in 165 overweight/obese subjects. There was no association between body mass index and DNA methylation of the five candidate genes in this group of subjects. Positive associations were observed between TNFα methylation and blood levels of LDL-C (β = 0.447, p = 0.002), TC/HDL-C (β = 0.467, p = 0.001) and LDL-C/HDL-C (β = 0.445, p = 0.002), as well as between HERV-w methylation and dietary intakes of β-carotene (β = 0.088, p = 0.051) and carotenoids (β = 0.083, p = 0.029). TNFα methylation showed negative associations with dietary intakes of cholesterol (β = −0.278, p = 0.048), folic acid (β = −0.339, p = 0.012), β-carotene (β = −0.332, p = 0.045), carotenoids (β = −0.331, p = 0.015) and retinol (β = −0.360, p = 0.008). These results suggest a complex relationship among nutrient intake, oxidative stress and DNA methylation.
Collapse
Affiliation(s)
- Valentina Bollati
- Center of Molecular and Genetic Epidemiology, Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan 20122, Italy.
| | - Chiara Favero
- Center of Molecular and Genetic Epidemiology, Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan 20122, Italy.
| | - Benedetta Albetti
- Center of Molecular and Genetic Epidemiology, Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan 20122, Italy.
| | - Letizia Tarantini
- Center of Molecular and Genetic Epidemiology, Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan 20122, Italy.
| | - Alice Moroni
- Center of Molecular and Genetic Epidemiology, Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan 20122, Italy.
| | - Hyang-Min Byun
- Laboratory of Environmental Epigenetics, Exposure Epidemiology and Risk Program, Harvard School of Public Health, Boston, MA 02115, USA.
| | - Valeria Motta
- Center of Molecular and Genetic Epidemiology, Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan 20122, Italy.
| | - Diana Misaela Conti
- Worker's Health Protection and Promotion Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan 20122, Italy.
| | - Amedea Silvia Tirelli
- Laboratory of Clinical Chemistry & Microbiology, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan 20122, Italy.
| | - Luisella Vigna
- Worker's Health Protection and Promotion Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan 20122, Italy.
| | - Pier Alberto Bertazzi
- Center of Molecular and Genetic Epidemiology, Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan 20122, Italy.
| | - Angela Cecilia Pesatori
- Center of Molecular and Genetic Epidemiology, Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Milan 20122, Italy.
| |
Collapse
|
28
|
Garcia-Etxebarria K, Jugo BM. Genomic environment and digital expression of bovine endogenous retroviruses. Gene 2014; 548:14-21. [DOI: 10.1016/j.gene.2014.06.048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 02/08/2014] [Accepted: 06/23/2014] [Indexed: 10/25/2022]
|
29
|
Garcia-Etxebarria K, Sistiaga-Poveda M, Jugo BM. Endogenous retroviruses in domestic animals. Curr Genomics 2014; 15:256-65. [PMID: 25132796 PMCID: PMC4133949 DOI: 10.2174/1389202915666140520003503] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 05/14/2014] [Accepted: 05/16/2014] [Indexed: 01/15/2023] Open
Abstract
Endogenous retroviruses (ERVs) are genomic elements that are present in a wide range of vertebrates. Although the study of ERVs has been carried out mainly in humans and model organisms, recently, domestic animals have become important, and some species have begun to be analyzed to gain further insight into ERVs. Due to the availability of complete genomes and the development of new computer tools, ERVs can now be analyzed from a genome-wide viewpoint. In addition, more experimental work is being carried out to analyze the distribution, expression and interplay of ERVs within a host genome. Cats, cattle, chicken, dogs, horses, pigs and sheep have been scrutinized in this manner, all of which are interesting species in health and economic terms. Furthermore, several studies have noted differences in the number of endogenous retroviruses and in the variability of these elements among different breeds, as well as their expression in different tissues and the effects of their locations, which, in some cases, are near genes. These findings suggest a complex, intriguing relationship between ERVs and host genomes. In this review, we summarize the most important in silico and experimental findings, discuss their implications and attempt to predict future directions for the study of these genomic elements.
Collapse
Affiliation(s)
- Koldo Garcia-Etxebarria
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila. Zientzia eta Teknologia Fakultatea. Euskal Herriko Unibertsitatea (UPV/EHU). 644 Postakutxa , E-48080 Bilbao, Spain
| | - Maialen Sistiaga-Poveda
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila. Zientzia eta Teknologia Fakultatea. Euskal Herriko Unibertsitatea (UPV/EHU). 644 Postakutxa , E-48080 Bilbao, Spain
| | - Begoña Marina Jugo
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila. Zientzia eta Teknologia Fakultatea. Euskal Herriko Unibertsitatea (UPV/EHU). 644 Postakutxa , E-48080 Bilbao, Spain
| |
Collapse
|
30
|
Human endogenous retrovirus W activity in cartilage of osteoarthritis patients. BIOMED RESEARCH INTERNATIONAL 2014; 2014:698609. [PMID: 25136615 PMCID: PMC4130134 DOI: 10.1155/2014/698609] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 06/25/2014] [Indexed: 11/18/2022]
Abstract
The etiology of viruses in osteoarthritis remains controversial because the prevalence of viral nucleic acid sequences in peripheral blood or synovial fluid from osteoarthritis patients and that in healthy control subjects are similar. Until now the presence of virus has not been analyzed in cartilage. We screened cartilage and chondrocytes from advanced and non-/early osteoarthritis patients for parvovirus B19, herpes simplex virus-1, Epstein Barr virus, cytomegalovirus, human herpes virus-6, hepatitis C virus, and human endogenous retroviruses transcripts. Endogenous retroviruses transcripts, but none of the other viruses, were detected in 15 out the 17 patients. Sequencing identified the virus as HERV-WE1 and E2. HERV-W activity was confirmed by high expression levels of syncytin, dsRNA, virus budding, and the presence of virus-like particles in all advanced osteoarthritis cartilages examined. Low levels of HERV-WE1, but not E2 envelope RNA, were observed in 3 out of 8 non-/early osteoarthritis patients, while only 3 out of 7 chondrocytes cultures displayed low levels of syncytin, and just one was positive for virus-like particles. This study demonstrates for the first time activation of HERV-W in cartilage of osteoarthritis patients; however, a causative role for HERV-W in development or deterioration of the disease remains to be proven.
Collapse
|
31
|
Abstract
BACKGROUND Many aspects of autoimmune disease are not well understood, including the specificities of autoimmune targets, and patterns of co-morbidity and cross-heritability across diseases. Prior work has provided evidence that somatic mutation caused by gene conversion and deletion at segmentally duplicated loci is relevant to several diseases. Simple tandem repeat (STR) sequence is highly mutable, both somatically and in the germ-line, and somatic STR mutations are observed under inflammation. RESULTS Protein-coding genes spanning STRs having markers of mutability, including germ-line variability, high total length, repeat count and/or repeat similarity, are evaluated in the context of autoimmunity. For the initiation of autoimmune disease, antigens whose autoantibodies are the first observed in a disease, termed primary autoantigens, are informative. Three primary autoantigens, thyroid peroxidase (TPO), phogrin (PTPRN2) and filaggrin (FLG), include STRs that are among the eleven longest STRs spanned by protein-coding genes. This association of primary autoantigens with long STR sequence is highly significant (p<3.0x10(-7)). Long STRs occur within twenty genes that are associated with sixteen common autoimmune diseases and atherosclerosis. The repeat within the TTC34 gene is an outlier in terms of length and a link with systemic lupus erythematosus is proposed. CONCLUSIONS The results support the hypothesis that many autoimmune diseases are triggered by immune responses to proteins whose DNA sequence mutates somatically in a coherent, consistent fashion. Other autoimmune diseases may be caused by coherent somatic mutations in immune cells. The coherent somatic mutation hypothesis has the potential to be a comprehensive explanation for the initiation of many autoimmune diseases.
Collapse
Affiliation(s)
- Kenneth Andrew Ross
- Department of Computer Science, Columbia University, New York, New York, United States of America
| |
Collapse
|
32
|
The participation of varicella zoster virus in relapses of multiple sclerosis. Clin Neurol Neurosurg 2014; 119:44-8. [PMID: 24635924 DOI: 10.1016/j.clineuro.2013.12.020] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 12/18/2013] [Accepted: 12/25/2013] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Recent studies have documented the apparent participation of varicella zoster virus (VZV) in the etiopathogenesis of multiple sclerosis (MS). The present study aimed to corroborate the possible presence of VZV during exacerbations of MS. DESIGN Fifty-three patients with definite MS were included; of them, 31 were studied during the first week of a clinical relapse, whereas 16 were studied during remission; 6 patients with progressive MS were also studied. Genes from 5 herpes viruses: varicella zoster, herpes simplex 1 and 2, Epstein-Barr and herpes 6 were studied by polymerase chain reaction in cerebrospinal fluid and in peripheral blood mononuclear cells (PBMC). As controls 21 patients with inflammatory or functional neurological disorders were included. RESULTS DNA from varicella zoster virus was found in the CSF from all MS patients studied during relapse (100%) and in the PBMC from 28 of them (90%). However, VZV DNA was found in the CSF only in 5 MS patients studied during remission (31%) and in the PBMC from 3 of them (19%). VZV DNA was also found, but in lower amounts, in the CSF (83%) and PBMC (33%) from patients with progressive MS. In contrast, VZV was not found either in CSF or in PBMC from controls. Results from the other herpes viruses tested were similar in MS patients and in controls. CONCLUSIONS Our results corroborate the conspicuous, but ephemeral presence of VZV during relapses of MS and support the idea of VZV involvement in the etiopathogenesis of MS. Recent epidemiological and molecular studies as well as reports of severe VZV infections triggered by specifically induced immunosuppression during therapy of MS give additional support to this potential association.
Collapse
|
33
|
Houenou J, d'Albis MA, Daban C, Hamdani N, Delavest M, Lepine JP, Vederine FE, Carde S, Lajnef M, Cabon C, Dickerson F, Yolken RH, Tamouza R, Poupon C, Leboyer M. Cytomegalovirus seropositivity and serointensity are associated with hippocampal volume and verbal memory in schizophrenia and bipolar disorder. Prog Neuropsychopharmacol Biol Psychiatry 2014; 48:142-8. [PMID: 24083998 DOI: 10.1016/j.pnpbp.2013.09.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 08/27/2013] [Accepted: 09/07/2013] [Indexed: 12/21/2022]
Abstract
INTRODUCTION Cytomegalovirus (CMV) is a member of the herpesviridae family that has a limbic and temporal gray matter tropism. It is usually latent in humans but has been associated with schizophrenia, bipolar disorder and cognitive deficits in some populations. Hippocampal decreased volume and dysfunction play a critical role in these cognitive deficits. We hypothesized that CMV seropositivity and serointensity would be associated with hippocampal volume and cognitive functioning in patients with schizophrenia or bipolar disorder. METHODS 102 healthy controls, 118 patients with bipolar disorder and 69 patients with schizophrenia performed the California Verbal Learning Test (CVLT) and had blood samples drawn to assess CMV IgG levels. A subgroup of 52 healthy controls, 31 patients with bipolar disorder and 27 patients with schizophrenia underwent T1 MRI for hippocampal volumetry. We analyzed the association between CMV serointensity and seropositivity with hippocampal volume. We also explored the correlation between CMV serointensity and seropositivity and CVLT scores. RESULTS In both patient groups but not in controls, higher CMV serointensity was significantly associated with smaller right hippocampal volume. Further, in the group of patients with schizophrenia but not bipolar disorder, CMV serointensity was negatively correlated with CVLT scores. CONCLUSION CMV IgG titers are associated with decreased hippocampal volume and poorer episodic verbal memory in patients with schizophrenia or bipolar disorder. The mechanism of this association warrants further exploration.
Collapse
Affiliation(s)
- J Houenou
- INSERM, U955, Equipe 15 "Psychiatrie Génétique", Créteil F-94000, France; Fondation Fondamental, Créteil F-94010, France; AP-HP, Groupe Henri Mondor - Albert Chenevier, Pôle de Psychiatrie, Créteil, F-94000, France; Neurospin, CEA Saclay, Gif-Sur-Yvette, France.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
34
|
HHV-6 and Multiple Sclerosis. HUMAN HERPESVIRUSES HHV-6A, HHV-6B & HHV-7 2014. [PMCID: PMC7152315 DOI: 10.1016/b978-0-444-62703-2.00007-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Multiple sclerosis (MS) is an inflammatory demyelinating disease affecting the central nervous system, thought to be an autoimmune disease mediated by autoreactive lymphocytes. The pathogenesis of MS is multifactorial and is thought to be triggered by multiple environmental factors in genetically susceptible individuals. Viruses have long been postulated as potential environmental triggers in MS, and there is increasing evidence of a link between viruses and MS. Some of the most compelling data have been found in human herpesvirus 6 (HHV-6) research. HHV-6 is a ubiquitous, neurotropic herpesvirus; HHV-6 DNA has been found in MS plaques compared to healthy brain tissue. Studies have also shown that MS patients have higher viral titers and higher DNA detection in serum and CSF compared to controls, and that the virus seems to be more actively replicating in MS patients. Potential mechanisms for HHV-6 leading to autoimmunity include molecular mimicry, bystander activation, and epitope spreading, among others.
Collapse
|
35
|
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: 29] [Impact Index Per Article: 2.9] [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.
| |
Collapse
|
36
|
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.
Collapse
Affiliation(s)
- Jane E Libbey
- Department of Pathology, University of Utah School of Medicine , Salt Lake City, UT , USAxs
| | | | | |
Collapse
|
37
|
Maliniemi P, Vincendeau M, Mayer J, Frank O, Hahtola S, Karenko L, Carlsson E, Mallet F, Seifarth W, Leib-Mösch C, Ranki A. Expression of human endogenous retrovirus-w including syncytin-1 in cutaneous T-cell lymphoma. PLoS One 2013; 8:e76281. [PMID: 24098463 PMCID: PMC3788054 DOI: 10.1371/journal.pone.0076281] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Accepted: 08/22/2013] [Indexed: 12/03/2022] Open
Abstract
The pathomechanism of mycosis fungoides (MF), the most common type of primary cutaneous T-cell lymphomas (CTCLs) and a malignancy of non-recirculating, skin-resident T-cells, is unknown albeit underlying viral infections have been sought for. Human endogenous retroviruses (HERVs) are ancient retroviral sequences in the human genome and their transcription is often deregulated in cancers. We explored the transcriptional activity of HERV sequences in a total of 34 samples comprising MF and psoriasis skin lesions, as well as corresponding non-malignant skin using a retrovirus-specific microarray and quantitative RT-PCR. To identify active HERV-W loci, we cloned the HERV-W specific RT-PCR products, sequenced the cDNA clones and assigned the sequences to HERV-W loci. Finally, we used immunohistochemistry on MF patient and non-malignant inflammatory skin samples to confirm specific HERV-encoded protein expression. Firstly, a distinct, skin-specific transcription profile consisting of five constitutively active HERV groups was established. Although individual variability was common, HERV-W showed significantly increased transcription in MF lesions compared to clinically intact skin from the same patient. Predominantly transcribed HERV-W loci were found to be located in chromosomes 6q21 and 7q21.2, chromosomal regions typically altered in CTCL. Surprisingly, we also found the expression of 7q21.2/ERVWE1-encoded Syncytin-1 (Env) protein in MF biopsies and expression of Syncytin-1 was seen in malignant lymphocytes, especially in the epidermotropic ones, in 15 of 30 cases studied. Most importantly, no Syncytin-1 expression was detected in inflammatory dermatosis (Lichen ruber planus) with skin-homing, non-malignant T lymphocytes. The expression of ERVWE1 mRNA was further confirmed in 3/7 MF lesions analyzed. Our observations strengthen the association between activated HERVs and cancer. The study offers a new perspective into the pathogenesis of CTCL since we demonstrate that differences in HERV-W transcription levels between lesional MF and non-malignant skin are significant, and that ERVWE1-encoded Syncytin-1 is expressed in MF lymphoma cells.
Collapse
Affiliation(s)
- Pilvi Maliniemi
- Department of Dermatology and Allergology, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland
- * E-mail:
| | - Michelle Vincendeau
- Institute of Virology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Research Unit Cellular Signal Integration, Institute of Molecular Toxicology and Pharmacology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Jens Mayer
- Department of Human Genetics, Center of Human and Molecular Biology, Medical Faculty, University of Saarland, Homburg, Germany
| | - Oliver Frank
- Department of Hematology and Oncology, Mannheim Medical Center, University of Heidelberg, Mannheim, Germany
| | - Sonja Hahtola
- Department of Dermatology and Allergology, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland
| | - Leena Karenko
- Department of Dermatology and Allergology, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland
| | - Emilia Carlsson
- Department of Dermatology and Allergology, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland
| | - Francois Mallet
- Joint Unit Hospices Civils de Lyon-bioMérieux, Cancer Biomarkers Research Group, Centre Hospitalier Lyon Sud, Pierre Bénite, France
| | - Wolfgang Seifarth
- Department of Hematology and Oncology, Mannheim Medical Center, University of Heidelberg, Mannheim, Germany
| | - Christine Leib-Mösch
- Institute of Virology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Department of Hematology and Oncology, Mannheim Medical Center, University of Heidelberg, Mannheim, Germany
| | - Annamari Ranki
- Department of Dermatology and Allergology, Helsinki University Central Hospital, University of Helsinki, Helsinki, Finland
| |
Collapse
|
38
|
Hon GM, Erasmus RT, Matsha T. Multiple sclerosis-associated retrovirus and related human endogenous retrovirus-W in patients with multiple sclerosis: A literature review. J Neuroimmunol 2013; 263:8-12. [DOI: 10.1016/j.jneuroim.2013.08.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 08/07/2013] [Indexed: 11/27/2022]
|
39
|
Abstract
Human herpesvirus (HHV-) 6A and HHV-6B are two distinct β-herpesviruses which have been associated with various neurological diseases, including encephalitis, meningitis, epilepsy, and multiple sclerosis. Although the reactivation of both viruses is recognized as the cause of some neurological complications in conditions of immunosuppression, their involvement in neuroinflammatory diseases in immunocompetent people is still unclear, and the mechanisms involved have not been completely elucidated. Here, we review the available data providing evidence for the capacity of HHV-6A and -6B to infect the central nervous system and to induce proinflammatory responses by infected cells. We discuss the potential role of both viruses in neuroinflammatory pathologies and the mechanisms which could explain virus-induced neuropathogenesis.
Collapse
Affiliation(s)
- Joséphine M. Reynaud
- International Center for Infectiology Research (CIRI), INSERM U1111, CNRS UMR5308, University of Lyon 1, ENS-Lyon, 21 Avenue T. Garnier, 69365 Lyon, France
| | - Branka Horvat
- International Center for Infectiology Research (CIRI), INSERM U1111, CNRS UMR5308, University of Lyon 1, ENS-Lyon, 21 Avenue T. Garnier, 69365 Lyon, France
| |
Collapse
|
40
|
Leboyer M, Tamouza R, Charron D, Faucard R, Perron H. Human endogenous retrovirus type W (HERV-W) in schizophrenia: a new avenue of research at the gene-environment interface. World J Biol Psychiatry 2013; 14:80-90. [PMID: 21936762 DOI: 10.3109/15622975.2010.601760] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVES Provide a synthetic review of recent studies evidencing an association between human endogenous retrovirus-W (HERV-W) and schizophrenia. METHODS Bibliography analysis and contextual synthesis. RESULTS Epidemiological studies suggest that the aetiology of schizophrenia is complex and involves a complex interplay of genetic and environmental factors such as infections. Eight percentof the human genome consists of human endogenous retroviruses (HERV), and this part of the genome was previously thought to be without importance, but new research has refuted this. HERVs share similarities with viruses and it is assumed that HERVs are present in the genome as a result of retroviruses infecting germ line cells many million years ago. A specific type of HERVs, called HERV-W, has through several recent studies been associated with schizophrenia. Elevated transcription of HERV-W elements has been documented, and antigens of HERV-W envelope and capsid proteins have been found in blood samples from patients. Viruses that have been implicated in pathology of schizophrenia, such as herpes and influenza, have been shown to activate HERV-W elements, and such activation has been associated with elevated biomarkers of systemic inflammation. New research indicates that HERV-W may be an important genetic factor interplaying with the environmental risk factor of infections and that, through this, HERV-W may be important for disease pathogenesis. CONCLUSIONS A lifelong scenario of a detrimental interaction between infectious agents and HERV-W genes may decipher the actual development and course of schizophrenia. Further research is needed to find out if specific treatment strategies could reduce the expression of HERV-W and if this will be associated with remission.
Collapse
Affiliation(s)
- Marion Leboyer
- AP-HP, Henri Mondor-Albert Chenevier Hospitals, Department of Psychiatry, Creteil, France
| | | | | | | | | |
Collapse
|
41
|
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.
Collapse
Affiliation(s)
- Marta Garcia-Montojo
- Multiple Sclerosis Unit, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos, Madrid, Spain.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Perron H, Hamdani N, Faucard R, Lajnef M, Jamain S, Daban-Huard C, Sarrazin S, LeGuen E, Houenou J, Delavest M, Moins-Teiserenc H, Bengoufa D, Yolken R, Madeira A, Garcia-Montojo M, Gehin N, Burgelin I, Ollagnier G, Bernard C, Dumaine A, Henrion A, Gombert A, Le Dudal K, Charron D, Krishnamoorthy R, Tamouza R, Leboyer M, Leboyer M. Molecular characteristics of Human Endogenous Retrovirus type-W in schizophrenia and bipolar disorder. Transl Psychiatry 2012; 2:e201. [PMID: 23212585 PMCID: PMC3565190 DOI: 10.1038/tp.2012.125] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Epidemiological and genome-wide association studies of severe psychiatric disorders such as schizophrenia (SZ) and bipolar disorder (BD), suggest complex interactions between multiple genetic elements and environmental factors. The involvement of genetic elements such as Human Endogenous Retroviruses type 'W' family (HERV-W) has consistently been associated with SZ. HERV-W envelope gene (env) is activated by environmental factors and encodes a protein displaying inflammation and neurotoxicity. The present study addressed the molecular characteristics of HERV-W env in SZ and BD. Hundred and thirty-six patients, 91 with BD, 45 with SZ and 73 healthy controls (HC) were included. HERV-W env transcription was found to be elevated in BD (P<10-4) and in SZ (P=0.012) as compared with HC, but with higher values in BD than in SZ group (P<0.01). The corresponding DNA copy number was paradoxically lower in the genome of patients with BD (P=0.0016) or SZ (P<0.0003) than in HC. Differences in nucleotide sequence of HERV-W env were found between patients with SZ and BD as compared with HC, as well as between SZ and BD. The molecular characteristics of HERV-W env also differ from what was observed in Multiple Sclerosis (MS) and may represent distinct features of the genome of patients with BD and SZ. The seroprevalence for Toxoplasma gondii yielded low but significant association with HERV-W transcriptional level in a subgroup of BD and SZ, suggesting a potential role in particular patients. A global hypothesis of mechanisms inducing such major psychoses is discussed, placing HERV-W at the crossroads between environmental, genetic and immunological factors. Thus, particular infections would act as activators of HERV-W elements in earliest life, resulting in the production of an HERV-W envelope protein, which then stimulates pro-inflammatory and neurotoxic cascades. This hypothesis needs to be further explored as it may yield major changes in our understanding and treatment of severe psychotic disorders.
Collapse
Affiliation(s)
- H Perron
- Geneuro, Plan-Les-Ouates, Geneva, Switzerland.
| | - N Hamdani
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France,Université Paris Est Créteil, Faculté de Médecine, Créteil, France
| | - R Faucard
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | - M Lajnef
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France
| | - S Jamain
- Inserm U955, Psychiatrie Génétique, Créteil, France,Fondation Fondamental, Créteil, France
| | - C Daban-Huard
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France
| | - S Sarrazin
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France,CEA Saclay, Neurospin, Gif-Sur-Yvette, France
| | - E LeGuen
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France
| | - J Houenou
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France,CEA Saclay, Neurospin, Gif-Sur-Yvette, France
| | - M Delavest
- Fondation Fondamental, Créteil, France,AP-HP, Université Paris Diderot, Service de Psychiatrie, Hôpital Lariboisiere Fernand Widal, Paris, France
| | - H Moins-Teiserenc
- Jean Dausset Department and INSERM UMRS 940, Hôpital Saint Louis, Paris, France
| | - D Bengoufa
- Jean Dausset Department and INSERM UMRS 940, Hôpital Saint Louis, Paris, France
| | - R Yolken
- Stanley Laboratory of Developmental Neurovirology, Johns Hopkins University Medical Center, Baltimore, MD, USA
| | - A Madeira
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | | | - N Gehin
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | - I Burgelin
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | - G Ollagnier
- Geneuro-Innovation, Pre-Clinical R&D Department, Lyon, France
| | - C Bernard
- Geneuro, Plan-Les-Ouates, Geneva, Switzerland
| | - A Dumaine
- Inserm U955, Psychiatrie Génétique, Créteil, France,Fondation Fondamental, Créteil, France
| | - A Henrion
- Inserm U955, Psychiatrie Génétique, Créteil, France,Fondation Fondamental, Créteil, France
| | - A Gombert
- Inserm U955, Psychiatrie Génétique, Créteil, France,Fondation Fondamental, Créteil, France
| | - K Le Dudal
- Plateforme de Ressources Biologiques AP-HP, Créteil, France,Stanley Research Program, Sheppard Pratt, Baltimore, MD, USA,INSERM-CIC 006, Créteil, France
| | - D Charron
- Jean Dausset Department and INSERM UMRS 940, Hôpital Saint Louis, Paris, France
| | | | - R Tamouza
- Jean Dausset Department and INSERM UMRS 940, Hôpital Saint Louis, Paris, France
| | - M Leboyer
- Inserm U955, Psychiatrie Génétique, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, Créteil, France,Fondation Fondamental, Créteil, France,Université Paris Est Créteil, Faculté de Médecine, Créteil, France,AP-HP, Hôpital Henri Mondor-Albert Chenevier, Pôle de Psychiatrie, 40, rue de Mesly, 94010 Créteil, France. E-mail:
| | | |
Collapse
|
43
|
Virtanen JO, Jacobson S. Viruses and multiple sclerosis. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2012; 11:528-44. [PMID: 22583435 DOI: 10.2174/187152712801661220] [Citation(s) in RCA: 116] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 04/13/2012] [Accepted: 04/20/2012] [Indexed: 11/22/2022]
Abstract
Multiple sclerosis (MS) is a heterogeneous disease that develops as an interplay between the immune system and environmental stimuli in genetically susceptible individuals. There is increasing evidence that viruses may play a role in MS pathogenesis acting as these environmental triggers. However, it is not known if any single virus is causal, or rather several viruses can act as triggers in disease development. Here, we review the association of different viruses to MS with an emphasis on two herpesviruses, Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6). These two agents have generated the most impact during recent years as possible co-factors in MS disease development. The strongest argument for association of EBV with MS comes from the link between symptomatic infectious mononucleosis and MS and from seroepidemiological studies. In contrast to EBV, HHV-6 has been found significantly more often in MS plaques than in MS normal appearing white matter or non-MS brains and HHV-6 re-activation has been reported during MS clinical relapses. In this review we also suggest new strategies, including the development of new infectious animal models of MS and antiviral MS clinical trials, to elucidate roles of different viruses in the pathogenesis of this disease. Furthermore, we introduce the idea of using unbiased sequence-independent pathogen discovery methodologies, such as next generation sequencing, to study MS brain tissue or body fluids for detection of known viral sequences or potential novel viral agents.
Collapse
Affiliation(s)
- Jussi Oskari Virtanen
- Viral Immunology Section, Neuroimmunology Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | | |
Collapse
|
44
|
Perron H, Germi R, Bernard C, Garcia-Montojo M, Deluen C, Farinelli L, Faucard R, Veas F, Stefas I, Fabriek BO, Van-Horssen J, Van-der-Valk P, Gerdil C, Mancuso R, Saresella M, Clerici M, Marcel S, Creange A, Cavaretta R, Caputo D, Arru G, Morand P, Lang AB, Sotgiu S, Ruprecht K, Rieckmann P, Villoslada P, Chofflon M, Boucraut J, Pelletier J, Hartung HP. Human endogenous retrovirus type W envelope expression in blood and brain cells provides new insights into multiple sclerosis disease. Mult Scler 2012; 18:1721-36. [PMID: 22457345 PMCID: PMC3573672 DOI: 10.1177/1352458512441381] [Citation(s) in RCA: 147] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Background: The envelope protein from multiple sclerosis (MS) associated retroviral element (MSRV), a member of the Human Endogenous Retroviral family ‘W’ (HERV-W), induces dysimmunity and inflammation. Objective: The objective of this study was to confirm and specify the association between HERV-W/MSRV envelope (Env) expression and MS. Methods: 103 MS, 199 healthy controls (HC) and controls with other neurological diseases (28), chronic infections (30) or autoimmunity (30) were analysed with an immunoassay detecting Env in serum. Env RNA or DNA copy numbers in peripheral blood mononuclear cells (PBMC) were determined by a quantitative polymerase chain reaction (PCR). Env was detected by immunohistology in the brains of patients with MS with three specific monoclonals. Results: Env antigen was detected in a serum of 73% of patients with MS with similar prevalence in all clinical forms, and not in chronic infection, systemic lupus, most other neurological diseases and healthy donors (p<0.01). Cases with chronic inflammatory demyelinating polyneuropathy (5/8) and rare HC (4/103) were positive. RNA expression in PBMC and DNA copy numbers were significantly elevated in patients with MS versus HC (p<0.001). In patients with MS, DNA copy numbers were significantly increased in chronic progressive MS (secondary progressive MS vs relapsing–remitting MS (RRMS) p<0.001; primary progressive MS vs RRMS –<0.02). Env protein was evidenced in macrophages within MS brain lesions with particular concentrations around vascular elements. Conclusion: The association between MS disease and the MSRV-type HERV-W element now appears quite strong, as evidenced ex-vivo from serum and PBMC with post-mortem confirmation in brain lesions. Chronic progressive MS, RRMS and clinically isolated syndrome show different ELISA (Enzyme-Linked Immunosorbent Assay) and/or PCR profiles suggestive of an increase with disease evolution, and amplicon sequencing confirms the association with particular HERV-W elements.
Collapse
|
45
|
Simpson S, Taylor B, Dwyer DE, Taylor J, Blizzard L, Ponsonby AL, Pittas F, Dwyer T, van der Mei I. Anti-HHV-6 IgG titer significantly predicts subsequent relapse risk in multiple sclerosis. Mult Scler 2011; 18:799-806. [PMID: 22084489 DOI: 10.1177/1352458511428081] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Some of the strongest associations with MS onset are for human herpesviruses, particularly Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6). Their role in MS clinical course is less clear, however. METHODS Prospective cohort of 198 persons with clinically definite MS, followed 2002-5, and serum samples obtained from all subjects at study entry to measure anti-HHV-6 and anti-EBV (Epstein-Barr nuclear antigen [EBNA] and viral capsid antigen [VCA]) IgG titers. Association with relapse evaluated using survival analysis; association with disability/progression evaluated using linear regression or multilevel mixed-effects linear regression. RESULTS For the 145 persons with relapsing-remitting MS followed beyond one review, anti-HHV-6 IgG titer was positively associated with the hazard of relapse with a dose-dependent trend (p = 0.003), not affected by adjustment for anti-EBV IgG titers, neither of which were independently associated with relapse. There was no significant association between anti-human herpesvirus IgG titers and baseline-measured disability scores, or change in disability scores; however, anti-HHV-6 IgG titers were 2.8 times higher among progressive-course females than progressive-course males. DISCUSSION These findings suggest that, in addition to a potential etiological role in MS, HHV-6 infection or the immune response to HHV-6 antigens may have an effect on the risk of MS relapses and possibly on progressive courses of MS. The observed effect was directly related to anti-HHV-6 IgG titers and may indicate that either HHV-6 infection or factors associated with an altered humoral immune response to HHV-6 may have an effect on MS clinical course. Anti-HHV-6 IgG titer may be a useful prognostic factor in relapsing-remitting MS clinical course.
Collapse
Affiliation(s)
- Steve Simpson
- 1Menzies Research Institute Tasmania, University of Tasmania, Australia
| | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Huang W, Li S, Hu Y, Yu H, Luo F, Zhang Q, Zhu F. Implication of the env gene of the human endogenous retrovirus W family in the expression of BDNF and DRD3 and development of recent-onset schizophrenia. Schizophr Bull 2011; 37:988-1000. [PMID: 20100784 PMCID: PMC3160218 DOI: 10.1093/schbul/sbp166] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE Retrovirus has been suggested as one of agents involved in the development of schizophrenia. In the present study, we examined the role of the human endogenous retrovirus W family (HERV-W) env gene in the etiopathogenesis of recent-onset schizophrenia, using molecular and epidemiological approaches. METHODS Nested RT-PCR was used to detect the messenger RNA (mRNA) of the HERV-w env gene in plasmas. Quantitative real-time polymerase chain reaction (PCR) was employed to detect the viral reverse transcriptase activity in human sera. Human U251 glioma cells were used to study the potential role of the HERV-W env gene in the etiopathogenesis of recent-onset schizophrenia. RESULTS We identified genes with mRNA sequences homologous to HERV-W env gene from plasmas of 42 out of 118 individuals with recent-onset schizophrenia but not from any of 106 normal persons (P < .01, t test). Quantitative real-time PCR showed a significantly increase in the reverse transcriptase activity in the sera of patients (by 35.59%) compared with controls (by 2.83%) (P < .05, t test). Overexpression of HERV-w env in human U251 glioma cells upregulated brain-derived neurotrophic factor (BDNF), an important schizophrenia-associated gene, neurotrophic tyrosine kinase receptor type 2 (NTRK2, also called TrkB), and dopamine receptor D3 and increased the phosphorylation of cyclic adenosine monophosphate response element-binding (CREB) protein. BDNF promoter reporter gene assays showed that the HERV-W env triggers BDNF production in human U251 glioma cells. Using gene knockdown, we found that CREB is required for the expression of BDNF that is regulated by env. CONCLUSION Our data revealed that the transcriptional activation of HERV is associated with the development of schizophrenia in some patients and indicated that HERV-W env regulates the expression of schizophrenia-associated genes. This report is the first to elucidate the signaling pathway responsible for the upregulation of HERV-W env-triggered BDNF. Our study provides new evidence for the involvement of HERV-W in the central nervous system, which will benefit the diagnosis and treatment of the devastating schizophrenia and related disorders.
Collapse
Affiliation(s)
- WenJie Huang
- Department of Medical Microbiology, School of Medicine, Wuhan University, 185 Donghu Road, Wuhan 430071, People's Republic of China,Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, People's Republic of China
| | - Shan Li
- Department of Medical Microbiology, School of Medicine, Wuhan University, 185 Donghu Road, Wuhan 430071, People's Republic of China
| | - YuanMing Hu
- School of Mathematics and Statistics, Wuhan University, Wuhan, People's Republic of China
| | - Honglian Yu
- Department of Medical Microbiology, School of Medicine, Wuhan University, 185 Donghu Road, Wuhan 430071, People's Republic of China
| | - Feng Luo
- School of Medicine, Jianghan University, Wuhan, People's Republic of China
| | - Qi Zhang
- School of Medicine, Stanford University, CA
| | - Fan Zhu
- Department of Medical Microbiology, School of Medicine, Wuhan University, 185 Donghu Road, Wuhan 430071, People's Republic of China,To whom correspondence should be addressed; tel: 86-27-68759906, e-mail:
| |
Collapse
|
47
|
|
48
|
Krone B, Grange JM. Paradigms in multiple sclerosis: time for a change, time for a unifying concept. Inflammopharmacology 2011; 19:187-95. [PMID: 21547536 PMCID: PMC3127006 DOI: 10.1007/s10787-011-0084-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2011] [Accepted: 04/09/2011] [Indexed: 12/12/2022]
Abstract
It has recently been suggested that, rather than being an autoimmune disease, multiple sclerosis (MS) is an example of a neurocristopathy, a pathological process resulting from a faulty development of the neural crest. Whilst several characteristics of the disease suggest a neurocristopathy, other aetiological factors require consideration, including hygiene-related factors that alter the immune responses to common pathogens resulting in an eclipse of immune reactivity that could protect against MS, the possible role of human endogenous retroviruses (HERVs) in pathogenesis and autoimmune phenomena, HLA polymorphism, vitamin D levels before and after birth and immune repair mechanisms. A postulated aetiological factor in MS, associated with altered vitamin D metabolism and abnormal HERV expression, is a long-lasting disturbed redox regulation in the biosynthesis of a melanoma-like melanin pigment. Although intensive further studies on melanin pigments in nerve tissue in MS are required, the known properties of a pathological form of such pigments in melanoma could explain a number of observations in MS, including the impact of light, UV-light, and vitamin D, and could explain the clinical manifestations of MS on the basis of an oscillating process of oxidative charge and discharge of the pigments and a threshold phenomenon with a change of the quasi-catalytic function of the pigment from destroying reactive oxygen radicals or species to transforming them to more harmful long-persisting highly reactive species. Taken together with the consequences of an adaptive process in partly demyelinated neurons, resulting in an increase in number of mitochondria, and the impact of stressful life events, these conditions are necessary and sufficient to explain the disease process of MS with its spatial (plaques) and temporal (attacks and remissions) characteristics. This suggested unifying concept of the pathogenesis of MS may open perspectives for prevention, diagnosis and therapy. In particular, prevention may be achieved by vaccinating against Epstein-Barr virus in early childhood.
Collapse
Affiliation(s)
- Bernd Krone
- Institute of Virology, Centre for Hygiene and Human Genetics, University of Göttingen, Kreuzbergring 57, 37075 Göttingen, Germany
| | | |
Collapse
|
49
|
Krone B, Grange JM. Multiple sclerosis: are protective immune mechanisms compromised by a complex infectious background? Autoimmune Dis 2010; 2011:708750. [PMID: 21197482 PMCID: PMC3010623 DOI: 10.4061/2011/708750] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2010] [Revised: 10/07/2010] [Accepted: 11/18/2010] [Indexed: 11/20/2022] Open
Abstract
The immunological background of multiple sclerosis (MS) manifests as an altered reactivity against a diverse range of infections, particularly with the Epstein-Barr virus. Although this could be only an epiphenomenon of a more generalised dysfunction of the immune system in MS, it is also possible that a complex infectious background forms the basis of a specific immune dysregulation finally causing the disease. It is thus suggested that the complex infectious background bears the key for an understanding of the immune pathogenesis of the disease. It appears probable that improved standards of hygiene cause regulatory defects in the immune system, allowing the abnormal expression of human endogenous retroviral (HERV) genes. On the basis of epidemiological observations we describe how a failure of expansion or an eclipse of a subfraction of self-antigen-specific CD8(+) T cells mediating immune repair, and a deleterious mode of action of HERV gene products, could underlie the pathogenesis of MS.
Collapse
Affiliation(s)
- Bernd Krone
- Institute of Virology, Centre for Hygiene and Human Genetics, University of Göttingen, Kreuzbergring 57, 37075 Göttingen, Germany
| | | |
Collapse
|
50
|
Genome-wide detection and characterization of endogenous retroviruses in Bos taurus. J Virol 2010; 84:10852-62. [PMID: 20686017 DOI: 10.1128/jvi.00106-10] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Endogenous retroviruses (ERVs) are the proviral phase of exogenous retroviruses that become integrated into a host germ line. They can play an important role in the host genome. Bioinformatic tools have been used to detect ERVs in several vertebrates, primarily primates and rodents. Less information is available regarding ERVs in other mammalian groups, and the source of this information is basically experimental. We analyzed the genome of the cow (Bos taurus) using three different methods. A BLAST-based method detected 928 possible ERVs, LTR_STRUC detected 4,487 elements flanked by long terminal repeats (LTRs), and Retrotector detected 9,698 ERVs. The ERVs were not homogeneously distributed across chromosomes; the number of ERVs was positively correlated with chromosomal size and negatively correlated with chromosomal GC content. The bovine ERVs (BoERVs) were classified into 24 putative families, with 20 of them not previously described. One of these new families, BoERV1, was the most abundant family and appeared to be specific to ruminants. An analysis of representatives of ERV families from rodents, primates, and ruminants showed a phylogenetic relationship following their hosts' relationships. This study demonstrates the importance of using multiple methods when trying to identify new ERVs and shows that the number of bovine ERV families is not as limited as previously thought.
Collapse
|