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] [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
|
Pourkarim MR. Navigating Evolving Challenges in Blood Safety. Viruses 2024; 16:123. [PMID: 38257823 PMCID: PMC10821029 DOI: 10.3390/v16010123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/11/2024] [Accepted: 01/14/2024] [Indexed: 01/24/2024] Open
Abstract
Blood safety remains a paramount public health concern, and health authorities maintain a high level of vigilance to prevent transfusion-transmitted infections (TTIs) [...].
Collapse
Affiliation(s)
- Mahmoud Reza Pourkarim
- Laboratory for Clinical and Epidemiological Virology, Rega Institute for Medical Research, Department of Microbiology, Immunology and Transplantation, KU Leuven, Herestraat 49, 3000 Leuven, Belgium;
- Health Policy Research Centre, Institute of Health, Shiraz University of Medical Sciences, Shiraz 71348-14336, Iran
- Blood Transfusion Research Centre, High Institute for Research and Education in Transfusion, Tehran 14665-1157, Iran
| |
Collapse
|
3
|
Kyriakou E, Magiorkinis G. Interplay between endogenous and exogenous human retroviruses. Trends Microbiol 2023; 31:933-946. [PMID: 37019721 DOI: 10.1016/j.tim.2023.03.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 03/09/2023] [Accepted: 03/13/2023] [Indexed: 04/07/2023]
Abstract
In humans, retroviruses thrive more as symbionts than as parasites. Apart from the only two modern exogenous human retroviruses (human T-cell lymphotropic and immunodeficiency viruses; HTLV and HIV, respectively), ~8% of the human genome is occupied by ancient retroviral DNA [human endogenous retroviruses (HERVs)]. Here, we review the recent discoveries about the interactions between the two groups, the impact of infection by exogenous retroviruses on the expression of HERVs, the effect of HERVs on the pathogenicity of HIV and HTLV and on the severity of the diseases caused by them, and the antiviral protection that HERVs can allegedly provide to the host. Tracing the crosstalk between contemporary retroviruses and their endogenized ancestors will provide better understanding of the retroviral world.
Collapse
Affiliation(s)
- Eleni Kyriakou
- Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Gkikas Magiorkinis
- Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece.
| |
Collapse
|
4
|
Rodrigues RB, Orsini M, Neves SV, de Rezende Pinto WBV, da Silva Catarino AM, Pereira DA, Oliveira ASB. Differential Diagnosis or Etiology: A Case Report on Amyotrophic Lateral Sclerosis-like Neuropathy Associated with HIV Infection. Curr HIV Res 2023; 21:323-329. [PMID: 37711011 DOI: 10.2174/1570162x21666230914104220] [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: 12/15/2022] [Revised: 07/20/2023] [Accepted: 08/18/2023] [Indexed: 09/16/2023]
Abstract
BACKGROUND Retroviruses are described as a risk factor for chronic neuropathy. However, it is still unknown if they can work as amyotrophic lateral sclerosis triggers. Over the years, some cases of this association have been described with heterogenous disclosures. CASE REPRESENTATION This study aimed to report a case of HIV and ALS-like neuropathy and briefly discuss peculiarities of clinical aspects, such as physiopathology and treatment options. The patient underwent neurological examination associated with blood tests, electromyography, analysis of cerebrospinal fluid, and imaging studies. DISCUSSION A non-systematic review was performed in major databases regarding the topic. The case presented mixed upper and lower motor neuron signs and was framed as a probable case of ALS following the present criteria. CONCLUSION After a short follow-up and viral load cleansing, neurological stabilization was achieved.
Collapse
Affiliation(s)
| | - Marco Orsini
- Neurology Department, Iguaçu University, Nova Iguaçu, Brazil
- Neurology Department, Federal University of Rio de Janeiro, Brazil
| | | | | | | | | | | |
Collapse
|
5
|
Chabukswar S, Grandi N, Tramontano E. Prolonged activity of HERV-K(HML2) in Old World Monkeys accounts for recent integrations and novel recombinant variants. Front Microbiol 2022; 13:1040792. [PMID: 36532485 PMCID: PMC9751479 DOI: 10.3389/fmicb.2022.1040792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 11/11/2022] [Indexed: 12/05/2022] Open
Abstract
Around 8% of the human genome comprises Human Endogenous Retroviruses (HERVs) acquired over primate evolution. Some are specific to primates such as HERV-K, consisting of 10 HML subtypes and including the most recently acquired elements. Particularly, HML2 is the youngest clade, having some human-specific integrations, and while it has been widely described in humans its presence and distribution in non-human primates remain poorly characterized. To investigate HML2 distribution in non-human primates, the present study focused on the characterization of HML2 integrations in Macaca fascicularis and Macaca mulatta which are the most evolutionarily distant species related to humans in the Catarrhini parvorder. We identified overall 208 HML2 proviruses for M. fascicularis (77) and M. mulatta (131). Among them, 46 proviruses are shared by the two species while the others are species specific. Only 12 proviruses were shared with humans, confirming that the major wave of HML2 diffusion in humans occurred after macaques' divergence. Phylogenetic analysis confirmed structural variations between HML2 macaques' species-specific proviruses, and the ones shared between macaques and humans. The HML2 loci were characterized in terms of structure, focusing on potential residual open reading frames (ORFs) for gag, pol, and env genes for the latter being reported to be expressed in human pathological conditions. The analysis identified highly conserved gag and pol genes, while the env genes had a very divergent nature. Of the 208 HML2 proviral sequences present in Macaca species, 81 sequences form a cluster having a MER11A, a characteristic HML8 LTR sequence, insertion in the env region indicating a recombination event that occurred between the HML2 env gene and the HML8 LTR. This recombination event, which was shown to be present only in a subset of macaques' shared sequences and species-specific sequences, highlights a recent viral activity leading to the emergence of an env variant specific to the Old World Monkeys (OWMs). We performed an exhaustive analysis of HML2 in two species of OWMs, in terms of its evolutionary history, structural features, and potential residual coding capacity highlighting recent activity of HML2 in macaques that occurred after its split from the Catarrhini parvorder, leading to the emergence of viral variants, hence providing a better understanding of the endogenization and diffusion of HML2 along primate evolution.
Collapse
|
6
|
Pérez-Pérez S, Domínguez-Mozo MI, García-Martínez MÁ, García-Frontini MC, Villarrubia N, Costa-Frossard L, Villar LM, Arroyo R, Álvarez-Lafuente R. Anti-Human Herpesvirus 6 A/B Antibodies Titers Correlate With Multiple Sclerosis-Associated Retrovirus Envelope Expression. Front Immunol 2021; 12:798003. [PMID: 34912348 PMCID: PMC8666430 DOI: 10.3389/fimmu.2021.798003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 11/11/2021] [Indexed: 12/23/2022] Open
Abstract
Human endogenous retrovirus W family envelope proteins (pHERV-W ENV/syncytin-1) have been repeatedly associated with multiple sclerosis (MS). Here, we have focused on the study of pHERV-W ENV/syncytin-1 expression levels in MS patients (relapsing and progressive forms) and in healthy donors (HD) and on exploring their possible relationship with Epstein-Barr virus (EBV) and human herpesvirus-6A/B (HHV-6A/B). We included blood samples from 101 MS patients and 37 HD to analyze antiviral antibody titers by ELISA and pHERV-W ENV/syncytin-1 expression levels by flow cytometry as well as by qPCR. Patients with relapsing MS forms showed significantly higher pHERV-W ENV/syncytin-1 protein and gene expression levels than HD. Progressive MS patients also showed significantly higher protein and gene expression levels than both HD and relapsing MS patients. Regarding antiviral antibodies titers, anti-HHV-6A/B IgM levels were positively correlated with pHERV-W ENV/syncytin-1 protein expression levels in patients with relapsing MS, while in the progressive forms patients this correlation was found with anti-HHVA/B IgG levels. Therefore, pHERV-W ENV could be involved in MS pathogenesis, playing a role in relapsing and progressive forms. Besides, anti-HHV-6A/B antibodies positively correlated with pHERV-W ENV expression. Further studies are needed to better understand this possible relationship.
Collapse
Affiliation(s)
- Silvia Pérez-Pérez
- Environmental Factors in Degenerative Diseases Research Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - María I. Domínguez-Mozo
- Environmental Factors in Degenerative Diseases Research Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - M. Ángel García-Martínez
- Environmental Factors in Degenerative Diseases Research Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - M. Celeste García-Frontini
- Environmental Factors in Degenerative Diseases Research Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| | - Noelia Villarrubia
- Immunology Department, Hospital Universitario Ramón y Cajal, Madrid, Spain
| | | | - Luisa M. Villar
- Immunology Department, Hospital Universitario Ramón y Cajal, Madrid, Spain
| | - Rafael Arroyo
- Neurology Department, Hospital Universitario Quironsalud Madrid, Madrid, Spain
| | - Roberto Álvarez-Lafuente
- Environmental Factors in Degenerative Diseases Research Group, Hospital Clínico San Carlos, Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid, Spain
| |
Collapse
|
7
|
Ferrari R, Grandi N, Tramontano E, Dieci G. Retrotransposons as Drivers of Mammalian Brain Evolution. Life (Basel) 2021; 11:life11050376. [PMID: 33922141 PMCID: PMC8143547 DOI: 10.3390/life11050376] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 12/11/2022] Open
Abstract
Retrotransposons, a large and diverse class of transposable elements that are still active in humans, represent a remarkable force of genomic innovation underlying mammalian evolution. Among the features distinguishing mammals from all other vertebrates, the presence of a neocortex with a peculiar neuronal organization, composition and connectivity is perhaps the one that, by affecting the cognitive abilities of mammals, contributed mostly to their evolutionary success. Among mammals, hominids and especially humans display an extraordinarily expanded cortical volume, an enrichment of the repertoire of neural cell types and more elaborate patterns of neuronal connectivity. Retrotransposon-derived sequences have recently been implicated in multiple layers of gene regulation in the brain, from transcriptional and post-transcriptional control to both local and large-scale three-dimensional chromatin organization. Accordingly, an increasing variety of neurodevelopmental and neurodegenerative conditions are being recognized to be associated with retrotransposon dysregulation. We review here a large body of recent studies lending support to the idea that retrotransposon-dependent evolutionary novelties were crucial for the emergence of mammalian, primate and human peculiarities of brain morphology and function.
Collapse
Affiliation(s)
- Roberto Ferrari
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy;
| | - Nicole Grandi
- Laboratory of Molecular Virology, Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (N.G.); (E.T.)
| | - Enzo Tramontano
- Laboratory of Molecular Virology, Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (N.G.); (E.T.)
- Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche, 09042 Monserrato, Italy
| | - Giorgio Dieci
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy;
- Correspondence:
| |
Collapse
|
8
|
Kristensen MK, Christensen T. Regulation of the expression of human endogenous retroviruses: elements in fetal development and a possible role in the development of cancer and neurological diseases. APMIS 2021; 129:241-253. [PMID: 33683784 DOI: 10.1111/apm.13130] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 03/03/2021] [Indexed: 12/14/2022]
Abstract
Human endogenous retroviruses (HERVs) are remnants of ancient retroviral germline infections. Most HERV sequences are silenced in somatic cells, but interest is emerging on the involvement of HERV derived transcripts and proteins in human physiology and disease. A HERV-W encoded protein, syncytin-1, has been co-opted into fetal physiology, where it plays a role in trophoblast formation. Altered HERV transcription and expression of HERV derived proteins are associated with various cancer types and neurological diseases such as multiple sclerosis (MS). The implication of HERVs as potential mediators of both health and disease suggests important roles of regulatory mechanisms and alterations of these in physiological and pathological processes. The regulation of HERV sequences is mediated by a wide variety of mechanisms, and the focus of this review is on selected aspects of these, including epigenetic mechanisms such as CpG methylation and histone modifications of the HP1-H3K9me axis, viral transactivation events, and regulatory perspectives of transient stimuli in the microenvironment. Increasing knowledge of the regulation of HERV sequences will not only contribute to the understanding of complex pathogeneses, but also may pinpoint potential targets for better diagnosis and treatment in complex diseases as MS.
Collapse
|
9
|
Glinsky GV. Genomics-Guided Drawing of Molecular and Pathophysiological Components of Malignant Regulatory Signatures Reveals a Pivotal Role in Human Diseases of Stem Cell-Associated Retroviral Sequences and Functionally-Active hESC Enhancers. Front Oncol 2021; 11:638363. [PMID: 33869024 PMCID: PMC8044830 DOI: 10.3389/fonc.2021.638363] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 03/10/2021] [Indexed: 12/31/2022] Open
Abstract
Repetitive DNA sequences (repeats) colonized two-third of human genome and a majority of repeats comprised of transposable genetic elements (TE). Evolutionary distinct categories of TE represent nucleic acid sequences that are repeatedly copied from and pasted into chromosomes at multiple genomic locations and acquired a multitude of regulatory functions. Here, genomics-guided maps of stemness regulatory signatures were drawn to dissect the contribution of TE to clinical manifestations of malignant phenotypes of human cancers. From patients’ and physicians’ perspectives, the clinical definition of a tumor’s malignant phenotype could be restricted to the early diagnosis of sub-types of malignancies with the increased risk of existing therapy failure and high likelihood of death from cancer. It is the viewpoint from which the understanding of stemness and malignant regulatory signatures is considered in this contribution. Genomics-guided analyses of experimental and clinical observations revealed the pivotal role of human stem cell-associated retroviral sequences (SCARS) in the origin and pathophysiology of clinically-lethal malignancies. SCARS were defined as the evolutionary- and biologically-related family of genomic regulatory sequences, the principal physiological function of which is to create and maintain the stemness phenotype during human preimplantation embryogenesis. For cell differentiation to occur, SCARS expression must be silenced and SCARS activity remains repressed in most terminally-differentiated human cells which are destined to perform specialized functions in the human body. Epigenetic reprogramming, de-repression, and sustained activity of SCARS results in various differentiation-defective phenotypes. One of the most prominent tissue- and organ-specific clinical manifestations of sustained SCARS activities is diagnosed as a pathological condition defined by a consensus of morphological, molecular, and genetic examinations as the malignant growth. Here, contemporary evidence are acquired, analyzed, and reported defining both novel diagnostic tools and druggable molecular targets readily amenable for diagnosis and efficient therapeutic management of clinically-lethal malignancies. These diagnostic and therapeutic approaches are based on monitoring of high-fidelity molecular signals of continuing SCARS activities in conjunction with genomic regulatory networks of thousands’ functionally-active embryonic enhancers affecting down-stream phenotype-altering genetic loci. Collectively, reported herein observations support a model of SCARS-activation triggered singular source code facilitating the intracellular propagation and intercellular (systemic) dissemination of disease states in the human body.
Collapse
Affiliation(s)
- Gennadi V Glinsky
- Institute of Engineering in Medicine, University of California, San Diego, CA, United States.,Department of Functional & Translational Genomics, OncoSCAR, Inc., Portland, OR, United States
| |
Collapse
|
10
|
Serati M, Esposito CM, Grassi S, Bollati V, Barkin JL, Buoli M. The Association between Plasma ERVWE1 Concentrations and Affective Symptoms during Pregnancy: Is This a Friendly Alien? INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17249217. [PMID: 33317172 PMCID: PMC7763945 DOI: 10.3390/ijerph17249217] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 12/02/2020] [Accepted: 12/08/2020] [Indexed: 12/24/2022]
Abstract
Human endogenous retroviruses (HERVs) comprise 8% of the human genome, and HERV DNA was reported to be essential in human embryonic development. Specifically, HERV-W encodes a protein, syncytin-1, alternatively known as ERVWE1 (Human Endogenous Retrovirus W EnvC7-1 Envelope Protein), participating in human placental morphogenesis and having a role in immune system regulation. Syncytin-1 activity is increased in neuropsychiatric disorders, autoimmune diseases, and cancer. In our study, forty-four women in the third trimester of pregnancy were tested for ERVWE1 plasma levels. In concomitance with blood samples the following rating scales were administered to women: the Edinburgh Postnatal Depression Scale (EPDS), State Anxiety Inventory (STAI-S), Trait Anxiety Inventory (STAI-T), and Prenatal Attachment Inventory (PAI). We found that higher ERVWE1 protein plasma levels were significantly associated with higher PAI scores (p = 0.02), an earlier gestational age at the time of blood collection (p = 0.01), a longer duration of symptoms (p = 0.03), and fewer lifetime attempted suicides (p = 0.02). Our results seem to support the role of ERVWE1 in maintaining clinical psychiatric symptoms as a result of potential prolonged inflammation. At the same time, this protein may have a protective role in pregnant women by a reduction of suicidal behavior and a better mother-fetus relationship.
Collapse
Affiliation(s)
- Marta Serati
- Department of Mental Health, ASST RHODENSE, 20024 Rho, Italy;
| | - Cecilia Maria Esposito
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy; (C.M.E.); (S.G.)
| | - Silvia Grassi
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy; (C.M.E.); (S.G.)
| | - Valentina Bollati
- EPIGET-Epidemiology, Epigenetics and Toxicology Lab-Department of Clinical Sciences and Community Health, University of Milan, 20122 Milan, Italy;
| | - Jennifer Lynn Barkin
- Department of Community Medicine, Mercer University School of Medicine, Macon, GA 31207, USA;
| | - Massimiliano Buoli
- Department of Pathophysiology and Transplantation, University of Milan, 20122 Milan, Italy; (C.M.E.); (S.G.)
- Department of Neurosciences and Mental Health, Fondazione IRCCS Ca’Granda Ospedale Maggiore Policlinico, Via F. Sforza 35, 20122 Milan, Italy
- Correspondence: ; Tel.: +39-02-55035983; Fax: +39-02-55033140
| |
Collapse
|
11
|
O'Carroll IP, Fan L, Kroupa T, McShane EK, Theodore C, Yates EA, Kondrup B, Ding J, Martin TS, Rein A, Wang YX. Structural Mimicry Drives HIV-1 Rev-Mediated HERV-K Expression. J Mol Biol 2020; 432:166711. [PMID: 33197463 DOI: 10.1016/j.jmb.2020.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 11/09/2020] [Accepted: 11/09/2020] [Indexed: 10/23/2022]
Abstract
Expression of the Human Endogenous Retrovirus Type K (HERV-K), the youngest and most active HERV, has been associated with various cancers and neurodegenerative diseases. As in all retroviruses, a fraction of HERV-K transcripts is exported from the nucleus in unspliced or incompletely spliced forms to serve as templates for translation of viral proteins. In a fraction of HERV-K loci (Type 2 proviruses), nuclear export of the unspliced HERV-K mRNA appears to be mediated by a cis-acting signal on the mRNA, the RcRE, and the protein Rec-these are analogous to the RRE-Rev system in HIV-1. Interestingly, the HIV-1 Rev protein is able to mediate the nuclear export of the HERV-K RcRE, contributing to elevated HERV-K expression in HIV-infected patients. We aimed to understand the structural basis for HIV Rev-HERV-K RcRE recognition. We examined the conformation of the RcRE RNA in solution using small-angle X-ray scattering (SAXS) and atomic force microscopy (AFM). We found that the 433-nt long RcRE can assume folded or extended conformations as observed by AFM. SAXS analysis of a truncated RcRE variant revealed an "A"-shaped topological structure similar to the one previously reported for the HIV-1 RRE. The effect of the overall topology was examined using several deletion variants. SAXS and biochemical analyses demonstrated that the "A" shape is necessary for efficient Rev-RcRE complex formation in vitro and nuclear export activity in cell culture. The findings provide insight into the mechanism of HERV-K expression and a structural explanation for HIV-1 Rev-mediated expression of HERV-K in HIV-infected patients. IMPORTANCE: Expression of the human endogenous retrovirus type K (HERV-K) has been associated with various cancers and autoimmune diseases. Nuclear export of both HIV-1 and HERV-K mRNAs is dependent on the interaction between a small viral protein (Rev in HIV-1 and Rec in HERV-K) and a region on the mRNA (RRE in HIV-1 and RcRE in HERV-K). HIV-1 Rev is able to mediate the nuclear export of RcRE-containing HERV-K mRNAs, which contributes to elevated production of HERV-K proteins in HIV-infected patients. We report the solution conformation of the RcRE RNA-the first three-dimensional topological structure for a HERV molecule-and find that the RcRE resembles the HIV-1 nuclear export signal, RRE. The finding reveals the structural basis for the increased HERV-K expression observed in HIV-infected patients. Elevated HERV expression, mediated by HIV infection or other stressors, can have various HERV-related biological consequences. The findings provide structural insight for regulation of HERV-K expression.
Collapse
Affiliation(s)
- Ina P O'Carroll
- Department of Chemistry, United States Naval Academy, Annapolis, MD 21402, USA.
| | - Lixin Fan
- Basic Science Program, Frederick National Laboratory for Cancer Research, SAXS Core Facility of the National Cancer Institute, Frederick, MD 21702, USA
| | - Tomáš Kroupa
- HIV Dynamics and Replication Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Erin K McShane
- Department of Chemistry, United States Naval Academy, Annapolis, MD 21402, USA
| | - Christophe Theodore
- Department of Chemistry, United States Naval Academy, Annapolis, MD 21402, USA
| | - Elizabeth A Yates
- Department of Chemistry, United States Naval Academy, Annapolis, MD 21402, USA
| | - Benjamin Kondrup
- Department of Chemistry, United States Naval Academy, Annapolis, MD 21402, USA
| | - Jienyu Ding
- Protein-Nucleic Acid Interaction Section, Structural Biophysics Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Tyler S Martin
- Department of Chemistry, United States Naval Academy, Annapolis, MD 21402, USA
| | - Alan Rein
- HIV Dynamics and Replication Program, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Yun-Xing Wang
- Protein-Nucleic Acid Interaction Section, Structural Biophysics Laboratory, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| |
Collapse
|
12
|
Dolci M, Favero C, Toumi W, Favi E, Tarantini L, Signorini L, Basile G, Bollati V, D'Alessandro S, Bagnoli P, Ferrante P, Delbue S. Human Endogenous Retroviruses Long Terminal Repeat Methylation, Transcription, and Protein Expression in Human Colon Cancer. Front Oncol 2020; 10:569015. [PMID: 33194657 PMCID: PMC7653092 DOI: 10.3389/fonc.2020.569015] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Accepted: 09/14/2020] [Indexed: 12/19/2022] Open
Abstract
Colon cancer is the fourth most common malignancy in both incidence and mortality in developed countries. Infectious agents are among the risk factors for colon cancer. Variations in human endogenous retrovirus (HERV) transcript and protein levels are associated with several types of cancers, but few studies address HERV expression in colon cancer. Fifty-eight patients with advanced-stage colon cancer were enrolled in this study. HERV-H, -K (HML-2), -P LTRs, Alu, and LINE-1 methylation levels and transcription of HERV-H, -K (HML-2), and -P env and HERV-K pol genes in normal adjacent and tumor tissues were investigated by pyrosequencing and RT-qPCR, respectively. Expression of the HERV-K (HML-2) Pol and Env proteins in selected tissues was examined by Western blotting. Associations between HERV transcript expression and methylation levels and between clinical characteristics and HERV expression were evaluated. Compared to adjacent normal tissues, LINE-1 was hypomethylated in tumor tissues (p < 0.05), whereas Alu, HERV-K (HML-2), and -H LTRs showed a decreasing trend in tumor tissue compared to normal tissue, though without a significant difference. The transcription levels of HERV env and pol genes were similar. However, the HERV-K (HML-2) Pol protein was more highly expressed (p < 0.01) in surrounding normal tissues, but the HERV-K (HML-2) Env protein was only expressed in tumor tissues. Although HERV LTR methylation and gene expression did not show significant differences between tumor and normal tissues, HERV protein expression differed greatly. Pol protein expression in normal cells may induce reverse transcription and subsequent integration into the host genome, likely favoring cell transformation; in contrast, the Env protein in tumor tissue may contribute to cancer progression through cell-to-cell fusion.
Collapse
Affiliation(s)
- Maria Dolci
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Chiara Favero
- EPIGET-Epidemiology, Epigenetics and Toxicology Lab, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Wafa Toumi
- Laboratory Services, Viral and Molecular Tumor Diagnostics Unit, Habib Thameur Hospital, Tunis, Tunisia
| | - Evaldo Favi
- Renal Transplantation, Fondazione Scientific Institute for Research, Hospitalization and Health Care Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy.,Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Letizia Tarantini
- EPIGET-Epidemiology, Epigenetics and Toxicology Lab, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Lucia Signorini
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Giuseppe Basile
- Orthopedic Department, San Siro Clinical Institute, Milan, Italy
| | - Valentina Bollati
- EPIGET-Epidemiology, Epigenetics and Toxicology Lab, Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Sarah D'Alessandro
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Pietro Bagnoli
- Surgical Department, Istituto Clinico Città Studi, Milan, Italy
| | - Pasquale Ferrante
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| | - Serena Delbue
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, Milan, Italy
| |
Collapse
|
13
|
Lathe R, St Clair D. From conifers to cognition: Microbes, brain and behavior. GENES BRAIN AND BEHAVIOR 2020; 19:e12680. [PMID: 32515128 DOI: 10.1111/gbb.12680] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 05/12/2020] [Accepted: 05/29/2020] [Indexed: 12/25/2022]
Abstract
A diversity of bacteria, protozoans and viruses ("endozoites") were recently uncovered within healthy tissues including the human brain. By contrast, it was already recognized a century ago that healthy plants tissues contain abundant endogenous microbes ("endophytes"). Taking endophytes as an informative precedent, we overview the nature, prevalence, and role of endozoites in mammalian tissues, centrally focusing on the brain, concluding that endozoites are ubiquitous in diverse tissues. These passengers often remain subclinical, but they are not silent. We address their routes of entry, mechanisms of persistence, tissue specificity, and potential to cause long-term behavioral changes and/or immunosuppression in mammals, where rabies virus is the exemplar. We extend the discussion to Herpesviridae, Coronaviridae, and Toxoplasma, as well as to diverse bacteria and yeasts, and debate the advantages and disadvantages that endozoite infection might afford to the host and to the ecosystem. We provide a clinical perspective in which endozoites are implicated in neurodegenerative disease, anxiety/depression, and schizophrenia. We conclude that endozoites are instrumental in the delicate balance between health and disease, including age-related brain disease, and that endozoites have played an important role in the evolution of brain function and human behavior.
Collapse
Affiliation(s)
- Richard Lathe
- Division of Infection Medicine, University of Edinburgh Medical School, Edinburgh, UK
| | - David St Clair
- Institute of Medical Sciences, School of Medicine, University of Aberdeen, Aberdeen, UK
| |
Collapse
|
14
|
Carstensen M, Christensen T, Stilund M, Møller HJ, Petersen EL, Petersen T. Activated monocytes and markers of inflammation in newly diagnosed multiple sclerosis. Immunol Cell Biol 2020; 98:549-562. [PMID: 32253768 PMCID: PMC7496724 DOI: 10.1111/imcb.12337] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 03/08/2020] [Accepted: 03/29/2020] [Indexed: 12/11/2022]
Abstract
In multiple sclerosis (MS), the inflammation and demyelination of the central nervous system (CNS) develop in distinct ways. This makes diagnosing patients difficult, imperative to initiating early and proper treatment. Several common features exist, among them a profound infiltration of monocytes into the CNS mediating demyelination and tissue destruction. In the periphery, monocytes are divided into three subsets depending on expression of CD14 and CD16, representing different stages of activation and differentiation. To investigate their involvement in MS, peripheral blood mononuclear cells (PBMCs) from 61 patients with incipient, untreated MS and 22 symptomatic control (SC) patients as well as 6 patients with radiologically isolated syndrome (RIS) were characterized ex vivo. In addition, paired serum and cerebrospinal fluid (CSF) samples were analyzed with a panel of biomarkers. In PBMC samples, we demonstrate decreased levels of nonclassical monocytes with a concomitant significant decrease of human endogenous retrovirus (HERV) H3 envelope epitopes on this monocyte subset compared with SC and RIS. The observed HERV expression is present on nonclassical monocytes irrespective of MS and thus presumably a result of the inflammatory activation. For the other surface markers analyzed, we found significantly decreased expression between classical and nonclassical monocytes. In matched samples of CSF a highly significant increase in levels of soluble markers of activation and inflammation is shown, and notably this is not the case for the serum samples. Of the soluble markers investigated, interleukin (IL)‐12/IL‐23p40 had the highest discriminatory power in differentiating patients with MS from SC and RIS, almost comparable to the immunoglobulin G index.
Collapse
Affiliation(s)
- Mikkel Carstensen
- Department of Biomedicine, Aarhus University, Skou Building, Høegh-Guldbergsgade 10, DK-8000, Aarhus C, Denmark
| | - Tove Christensen
- Department of Biomedicine, Aarhus University, Skou Building, Høegh-Guldbergsgade 10, DK-8000, Aarhus C, Denmark
| | - Morten Stilund
- Department of Biomedicine, Aarhus University, Skou Building, Høegh-Guldbergsgade 10, DK-8000, Aarhus C, Denmark.,Department of Neurology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 165, DK-8200, Aarhus N, Denmark
| | - Holger J Møller
- Department of Clinical Biochemistry, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, DK-8200, Aarhus N, Denmark
| | - Eva L Petersen
- Department of Biomedicine, Aarhus University, Skou Building, Høegh-Guldbergsgade 10, DK-8000, Aarhus C, Denmark
| | - Thor Petersen
- Department of Neurology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 165, DK-8200, Aarhus N, Denmark
| |
Collapse
|
15
|
Bendall ML, de Mulder M, Iñiguez LP, Lecanda-Sánchez A, Pérez-Losada M, Ostrowski MA, Jones RB, Mulder LCF, Reyes-Terán G, Crandall KA, Ormsby CE, Nixon DF. Telescope: Characterization of the retrotranscriptome by accurate estimation of transposable element expression. PLoS Comput Biol 2019; 15:e1006453. [PMID: 31568525 PMCID: PMC6786656 DOI: 10.1371/journal.pcbi.1006453] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 10/10/2019] [Accepted: 09/17/2019] [Indexed: 12/20/2022] Open
Abstract
Characterization of Human Endogenous Retrovirus (HERV) expression within the transcriptomic landscape using RNA-seq is complicated by uncertainty in fragment assignment because of sequence similarity. We present Telescope, a computational software tool that provides accurate estimation of transposable element expression (retrotranscriptome) resolved to specific genomic locations. Telescope directly addresses uncertainty in fragment assignment by reassigning ambiguously mapped fragments to the most probable source transcript as determined within a Bayesian statistical model. We demonstrate the utility of our approach through single locus analysis of HERV expression in 13 ENCODE cell types. When examined at this resolution, we find that the magnitude and breadth of the retrotranscriptome can be vastly different among cell types. Furthermore, our approach is robust to differences in sequencing technology and demonstrates that the retrotranscriptome has potential to be used for cell type identification. We compared our tool with other approaches for quantifying transposable element (TE) expression, and found that Telescope has the greatest resolution, as it estimates expression at specific TE insertions rather than at the TE subfamily level. Telescope performs highly accurate quantification of the retrotranscriptomic landscape in RNA-seq experiments, revealing a differential complexity in the transposable element biology of complex systems not previously observed. Telescope is available at https://github.com/mlbendall/telescope. Almost half of the human genome is composed of transposable elements (TEs), but their contribution to the transcriptome, their cell-type specific expression patterns, and their role in disease remains poorly understood. Recent studies have found many elements to be actively expressed and involved in key cellular processes. For example, human endogenous retroviruses (HERVs) are reported to be involved in human embryonic stem cell differentiation. Discovering which exact HERVs are differentially expressed in RNA-seq data would be a major advance in understanding such processes. However, because HERVs have a high level of sequence similarity it is hard to identify which exact HERV is differentially expressed. To solve this problem, we developed a computer program which addressed uncertainty in fragment assignment by reassigning ambiguously mapped fragments to the most probable source transcript as determined within a Bayesian statistical model. We call this program, “Telescope”. We then used Telescope to identify HERV expression in 13 well-studied cell types from the ENCODE consortium and found that different cell types could be characterized by enrichment for different HERV families, and for locus specific expression. We also showed that Telescope performed better than other methods currently used to determine TE expression. The use of this computational tool to examine new and existing RNA-seq data sets may lead to new understanding of the roles of TEs in health and disease.
Collapse
Affiliation(s)
- Matthew L. Bendall
- Computational Biology Institute, Milken Institute School of Public Health, George Washington University, Washington, D.C., United States of America
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, N.Y., United States of America
- * E-mail:
| | - Miguel de Mulder
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, N.Y., United States of America
| | - Luis Pedro Iñiguez
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, N.Y., United States of America
- Center for Research in Infectious Diseases (CIENI), Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Aarón Lecanda-Sánchez
- Center for Research in Infectious Diseases (CIENI), Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Marcos Pérez-Losada
- Computational Biology Institute, Milken Institute School of Public Health, George Washington University, Washington, D.C., United States of America
- Department of Biostatistics and Bioinformatics, Milken Institute School of Public Health, George Washington University, Washington, D.C., United States of America
- CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Universidade do Porto, Campus Agrário de Vairão, Vairão, Portugal
| | - Mario A. Ostrowski
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
- Keenan Research Centre for Biomedical Science of St. Michael's Hospital, Toronto, Ontario, Canada
| | - R. Brad Jones
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, N.Y., United States of America
| | - Lubbertus C. F. Mulder
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- The Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Gustavo Reyes-Terán
- Center for Research in Infectious Diseases (CIENI), Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Keith A. Crandall
- Computational Biology Institute, Milken Institute School of Public Health, George Washington University, Washington, D.C., United States of America
- Department of Biostatistics and Bioinformatics, Milken Institute School of Public Health, George Washington University, Washington, D.C., United States of America
| | - Christopher E. Ormsby
- Center for Research in Infectious Diseases (CIENI), Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico
| | - Douglas F. Nixon
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, N.Y., United States of America
| |
Collapse
|
16
|
Azébi S, Batsché E, Michel F, Kornobis E, Muchardt C. Expression of endogenous retroviruses reflects increased usage of atypical enhancers in T cells. EMBO J 2019; 38:embj.2018101107. [PMID: 31068361 DOI: 10.15252/embj.2018101107] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2018] [Revised: 03/20/2019] [Accepted: 03/28/2019] [Indexed: 01/02/2023] Open
Abstract
Several autoimmune diseases including multiple sclerosis (MS) cause increased transcription of endogenous retroviruses (HERVs) normally repressed by heterochromatin. In parallel, HERV-derived sequences were reported to drive gene expression. Here, we have examined a possible link between promoter and enhancer divergent transcription and the production of HERV transcripts. We find that HERV-derived sequences are in general counter-selected at regulatory regions, a counter-selection that is strongest in brain tissues while very moderate in stem cells. By exposing T cells to the pesticide dieldrin, we further found that a series of HERV-driven enhancers otherwise active only at stem cell stages can be reactivated by stress. This in part relies on peptidylarginine deiminase activity, possibly participating in the reawakening of silenced enhancers. Likewise, usage of HERV-driven enhancers was increased in myelin-reactive T cells from patients with MS, correlating with activation of nearby genes at several sites. Altogether, we propose that HERV-driven enhancers constitute a reservoir of auxiliary enhancers transiently induced by stress while chronically active in diseases like MS.
Collapse
Affiliation(s)
- Saliha Azébi
- Unité de Régulation Epigénétique, UMR3738, CNRS, Institut Pasteur, Paris, France.,Unit of Cytokine Signaling, Department of Immunology, Institut Pasteur, Paris, France
| | - Eric Batsché
- Unité de Régulation Epigénétique, UMR3738, CNRS, Institut Pasteur, Paris, France
| | - Frédérique Michel
- Ecole Doctorale "Complexité du Vivant" (ED515), Sorbonne Université, Paris, France
| | - Etienne Kornobis
- Unité de Régulation Epigénétique, UMR3738, CNRS, Institut Pasteur, Paris, France
| | - Christian Muchardt
- Unité de Régulation Epigénétique, UMR3738, CNRS, Institut Pasteur, Paris, France
| |
Collapse
|
17
|
Bodea GO, McKelvey EGZ, Faulkner GJ. Retrotransposon-induced mosaicism in the neural genome. Open Biol 2019; 8:rsob.180074. [PMID: 30021882 PMCID: PMC6070720 DOI: 10.1098/rsob.180074] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/21/2018] [Indexed: 12/18/2022] Open
Abstract
Over the past decade, major discoveries in retrotransposon biology have depicted the neural genome as a dynamic structure during life. In particular, the retrotransposon LINE-1 (L1) has been shown to be transcribed and mobilized in the brain. Retrotransposition in the developing brain, as well as during adult neurogenesis, provides a milieu in which neural diversity can arise. Dysregulation of retrotransposon activity may also contribute to neurological disease. Here, we review recent reports of retrotransposon activity in the brain, and discuss the temporal nature of retrotransposition and its regulation in neural cells in response to stimuli. We also put forward hypotheses regarding the significance of retrotransposons for brain development and neurological function, and consider the potential implications of this phenomenon for neuropsychiatric and neurodegenerative conditions.
Collapse
Affiliation(s)
- Gabriela O Bodea
- Mater Research Institute-University of Queensland, TRI Building, Brisbane, Queensland 4102, Australia .,Queensland Brain Institute, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Eleanor G Z McKelvey
- Queensland Brain Institute, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Geoffrey J Faulkner
- Mater Research Institute-University of Queensland, TRI Building, Brisbane, Queensland 4102, Australia .,Queensland Brain Institute, University of Queensland, Brisbane, Queensland 4072, Australia
| |
Collapse
|
18
|
The Arc gene: Retroviral heritage in cognitive functions. Neurosci Biobehav Rev 2019; 99:275-281. [PMID: 30772431 DOI: 10.1016/j.neubiorev.2019.02.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 01/29/2019] [Accepted: 02/12/2019] [Indexed: 12/22/2022]
Abstract
Stabilization of neuronal plastic changes is mediated by transient gene expression, including transcription of the activity-regulated cytoskeleton-associated gene (Arc), also known as Arg 3.1. Arc is implicated in several types of synaptic plasticity, including synaptic scaling, long-term potentiation, and long-term depression. However, the precise mechanisms by which Arc mediates these forms of long-term plasticity are unclear. It was recently found that Arc protein is capable of forming capsid-like structures and of transferring its own mRNA to neighboring cells. Moreover, Arc mRNA undergoes activity-dependent translation in these "transfected" cells. These new data raise unexpected possibilities for the mechanisms of the Arc action, and many intriguing questions concerning the role of Arc transcellular traffic in neuronal plasticity. In this mini-review, we discuss a possible link between the role of Arc in learning and memory and the virus-like properties of this protein. Additionally, we highlight some of the emerging questions for future neurobiological studies and translational applications of Arc transsynaptic effects.
Collapse
|
19
|
Genomic Analyses of Acute Flaccid Myelitis Cases among a Cluster in Arizona Provide Further Evidence of Enterovirus D68 Role. mBio 2019; 10:mBio.02262-18. [PMID: 30670612 PMCID: PMC6343034 DOI: 10.1128/mbio.02262-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Enteroviruses frequently result in respiratory and gastrointestinal illness; however, multiple subtypes, including poliovirus, can cause severe neurologic disease. Recent biennial increases (i.e., 2014, 2016, and 2018) in cases of non-polio acute flaccid paralysis have led to speculations that other enteroviruses, specifically enterovirus D68 (EV-D68), are emerging to fill the niche that was left from poliovirus eradication. A cluster of 11 suspect cases of pediatric acute flaccid myelitis (AFM) was identified in 2016 in Phoenix, AZ. Multiple genomic analyses identified the presence of EV-D68 in the majority of clinical AFM cases. Beyond limited detection of herpesvirus, no other likely etiologies were found in the cluster. These findings strengthen the likelihood that EV-D68 is a cause of AFM and show that the rapid molecular assays developed for this study are useful for investigations of AFM and EV-D68. Enteroviruses are a common cause of respiratory and gastrointestinal illness, and multiple subtypes, including poliovirus, can cause neurologic disease. In recent years, enterovirus D68 (EV-D68) has been associated with serious neurologic illnesses, including acute flaccid myelitis (AFM), frequently preceded by respiratory disease. A cluster of 11 suspect cases of pediatric AFM was identified in September 2016 in Phoenix, AZ. To determine if these cases were associated with EV-D68, we performed multiple genomic analyses of nasopharyngeal (NP) swabs and cerebrospinal fluid (CSF) material from the patients, including real-time PCR and amplicon sequencing targeting the EV-D68 VP1 gene and unbiased microbiome and metagenomic sequencing. Four of the 11 patients were classified as confirmed cases of AFM, and an additional case was classified as probable AFM. Real-time PCR and amplicon sequencing detected EV-D68 virus RNA in the three AFM patients from which NP swabs were collected, as well as in a fourth patient diagnosed with acute disseminated encephalomyelitis, a disease that commonly follows bacterial or viral infections, including enterovirus. No other obvious etiological causes for AFM were identified by 16S or RNA and DNA metagenomic sequencing in these cases, strengthening the likelihood that EV-D68 is an etiological factor. Herpes simplex viral DNA was detected in the CSF of the fourth case of AFM and in one additional suspect case from the cluster. Multiple genomic techniques, such as those described here, can be used to diagnose patients with suspected EV-D68 respiratory illness, to aid in AFM diagnosis, and for future EV-D68 surveillance and epidemiology.
Collapse
|
20
|
Mayer J, Harz C, Sanchez L, Pereira GC, Maldener E, Heras SR, Ostrow LW, Ravits J, Batra R, Meese E, García-Pérez JL, Goodier JL. Transcriptional profiling of HERV-K(HML-2) in amyotrophic lateral sclerosis and potential implications for expression of HML-2 proteins. Mol Neurodegener 2018; 13:39. [PMID: 30068350 PMCID: PMC6091006 DOI: 10.1186/s13024-018-0275-3] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 07/23/2018] [Indexed: 12/12/2022] Open
Abstract
Background Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder. About 90% of ALS cases are without a known genetic cause. The human endogenous retrovirus multi-copy HERV-K(HML-2) group was recently reported to potentially contribute to neurodegeneration and disease pathogenesis in ALS because of transcriptional upregulation and toxic effects of HML-2 Envelope (Env) protein. Env and other proteins are encoded by some transcriptionally active HML-2 loci. However, more detailed information is required regarding which HML-2 loci are transcribed in ALS, which of their proteins are expressed, and differences between the disease and non-disease states. Methods For brain and spinal cord tissue samples from ALS patients and controls, we identified transcribed HML-2 loci by generating and mapping HML-2-specific cDNA sequences. We predicted expression of HML-2 env gene-derived proteins based on the observed cDNA sequences. Furthermore, we determined overall HML-2 transcript levels by RT-qPCR and investigated presence of HML-2 Env protein in ALS and control tissue samples by Western blotting. Results We identified 24 different transcribed HML-2 loci. Some of those loci are transcribed at relatively high levels. However, significant differences in HML-2 loci transcriptional activities were not seen when comparing ALS and controls. Likewise, overall HML-2 transcript levels, as determined by RT-qPCR, were not significantly different between ALS and controls. Indeed, we were unable to detect full-length HML-2 Env protein in ALS and control tissue samples despite reasonable sensitivity. Rather our analyses suggest that a number of HML-2 protein variants other than full-length Env may potentially be expressed in ALS patients. Conclusions Our results expand and refine recent publications on HERV-K(HML-2) and ALS. Some of our results are in conflict with recent findings and call for further specific analyses. Our profiling of HML-2 transcription in ALS opens up the possibility that HML-2 proteins other than canonical full-length Env may have to be considered when studying the role of HML-2 in ALS disease. Electronic supplementary material The online version of this article (10.1186/s13024-018-0275-3) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Jens Mayer
- Department of Human Genetics, University of Saarland, Homburg, Germany.
| | - Christian Harz
- Department of Human Genetics, University of Saarland, Homburg, Germany
| | - Laura Sanchez
- GENYO. Centre for Genomics and Oncological Research: Pfizer, University of Granada, Andalusian Regional Government, Granada, Spain
| | - Gavin C Pereira
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Esther Maldener
- Department of Human Genetics, University of Saarland, Homburg, Germany
| | - Sara R Heras
- GENYO. Centre for Genomics and Oncological Research: Pfizer, University of Granada, Andalusian Regional Government, Granada, Spain.,Department of Biochemistry and Molecular Biology II, Faculty of Pharmacy, University of Granada, Campus Universitario de Cartuja, 18071, Granada, Spain
| | - Lyle W Ostrow
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 28217, USA
| | - John Ravits
- Department of Neurosciences, School of Medicine, UCSD, San Diego, CA, USA
| | - Ranjan Batra
- Department of Neurosciences, School of Medicine, UCSD, San Diego, CA, USA
| | - Eckart Meese
- Department of Human Genetics, University of Saarland, Homburg, Germany
| | - Jose Luis García-Pérez
- GENYO. Centre for Genomics and Oncological Research: Pfizer, University of Granada, Andalusian Regional Government, Granada, Spain.,MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine (IGMM), University of Edinburgh, Western General Hospital, Edinburgh, UK
| | - John L Goodier
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| |
Collapse
|
21
|
Turnbull MG, Douville RN. Related Endogenous Retrovirus-K Elements Harbor Distinct Protease Active Site Motifs. Front Microbiol 2018; 9:1577. [PMID: 30072963 PMCID: PMC6058741 DOI: 10.3389/fmicb.2018.01577] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/25/2018] [Indexed: 02/06/2023] Open
Abstract
Background: Endogenous retrovirus-K is a group of related genomic elements descending from retroviral infections in human ancestors. HML2 is the clade of these viruses which contains the most intact provirus copies. These elements can be transcribed and translated in healthy and diseased tissues, and some of them produce active retroviral enzymes, such as protease. Retroviral gene products, including protease, contribute to illness in exogenous retroviral infections. There are ongoing efforts to test anti-retroviral regimens against endogenous retroviruses. Herein, we examine the potential activity and diversity of human endogenous retrovirus-K proteases, and their potential for impact on immunity and human disease. Results: Sequences similar to the endogenous retrovirus-K HML2 protease and reverse transcriptase were identified in the human genome, classified by phylogenetic inference and compared to Repbase reference sequences. The topologies of trees inferred from protease and reverse transcriptase sequences were similar and agreed with the classification using reference sequences. Surprisingly, only 62/480 protease sequences identified by BLAST were classified as HML2; the remainder were classified as other HML groups, with the majority (216) classified as HML3. Variation in functionally significant protease motifs was explored, and two major active site variants were identified – the DTGAD variant is common in all groups, but the DTGVD motif appears limited to HML3, HML5, and HML6. Furthermore, distinct RNA expression patterns of protease variants are seen in disease states, such as amyotrophic lateral sclerosis, breast cancer, and prostate cancer. Conclusion: Transcribed ERVK proteases exhibit a diversity which could impact immunity and inhibitor-based treatments, and these facets should be considered when designing therapeutic regimens.
Collapse
Affiliation(s)
| | - Renée N Douville
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada.,Department of Immunology, University of Manitoba, Winnipeg, MB, Canada
| |
Collapse
|
22
|
ALSUntangled 45: Antiretrovirals. Amyotroph Lateral Scler Frontotemporal Degener 2018; 19:630-634. [PMID: 29693424 DOI: 10.1080/21678421.2018.1465248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
23
|
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
|
24
|
Grandi N, Cadeddu M, Blomberg J, Mayer J, Tramontano E. HERV-W group evolutionary history in non-human primates: characterization of ERV-W orthologs in Catarrhini and related ERV groups in Platyrrhini. BMC Evol Biol 2018; 18:6. [PMID: 29351742 PMCID: PMC5775608 DOI: 10.1186/s12862-018-1125-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 01/14/2018] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND The genomes of all vertebrates harbor remnants of ancient retroviral infections, having affected the germ line cells during the last 100 million years. These sequences, named Endogenous Retroviruses (ERVs), have been transmitted to the offspring in a Mendelian way, being relatively stable components of the host genome even long after their exogenous counterparts went extinct. Among human ERVs (HERVs), the HERV-W group is of particular interest for our physiology and pathology. A HERV-W provirus in locus 7q21.2 has been coopted during evolution to exert an essential role in placenta, and the group expression has been tentatively linked to Multiple Sclerosis and other diseases. Following up on a detailed analysis of 213 HERV-W insertions in the human genome, we now investigated the ERV-W group genomic spread within primate lineages. RESULTS We analyzed HERV-W orthologous loci in the genome sequences of 12 non-human primate species belonging to Simiiformes (parvorders Catarrhini and Platyrrhini), Tarsiiformes and to the most primitive Prosimians. Analysis of HERV-W orthologous loci in non-human Catarrhini primates revealed species-specific insertions in the genomes of Chimpanzee (3), Gorilla (4), Orangutan (6), Gibbon (2) and especially Rhesus Macaque (66). Such sequences were acquired in a retroviral fashion and, in the majority of cases, by L1-mediated formation of processed pseudogenes. There were also a number of LTR-LTR homologous recombination events that occurred subsequent to separation of Catarrhini sub-lineages. Moreover, we retrieved 130 sequences in Marmoset and Squirrel Monkeys (family Cebidae, Platyrrhini parvorder), identified as ERV1-1_CJa based on RepBase annotations, which appear closely related to the ERV-W group. Such sequences were also identified in Atelidae and Pitheciidae, representative of the other Platyrrhini families. In contrast, no ERV-W-related sequences were found in genome sequence assemblies of Tarsiiformes and Prosimians. CONCLUSIONS Overall, our analysis now provides a detailed picture of the ERV-W sequences colonization of the primate lineages genomes, revealing the exact dynamics of ERV-W locus formations as well as novel insights into the evolution and origin of the group.
Collapse
Affiliation(s)
- Nicole Grandi
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Marta Cadeddu
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
| | - Jonas Blomberg
- Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Jens Mayer
- Institute of Human Genetics, University of Saarland, Homburg, Germany
| | - Enzo Tramontano
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Italy
- Istituto di Ricerca Genetica e Biomedica (IRGB), CNR, Monserrato, Italy
| |
Collapse
|
25
|
High expression of Endogenous Retroviruses from intrauterine life to adulthood in two mouse models of Autism Spectrum Disorders. Sci Rep 2018; 8:629. [PMID: 29330412 PMCID: PMC5766538 DOI: 10.1038/s41598-017-19035-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 12/12/2017] [Indexed: 12/19/2022] Open
Abstract
Retroelements, such as Human Endogenous Retroviruses (HERVs), have been implicated in many complex diseases, including neurological and neuropsychiatric disorders. Previously, we demonstrated a distinctive expression profile of specific HERV families in peripheral blood mononuclear cells from Autistic Spectrum Disorders (ASD) patients, suggesting their involvement in ASD. Here we used two distinct ASD mouse models: inbred BTBR T+tf/J mice and CD-1 outbred mice prenatally exposed to valproic acid. Whole embryos, blood and brain samples from the offspring were collected at different ages and the expression of several ERV families (ETnI, ETnII-α, ETnII-β, ETnII-γ, MusD and IAP), proinflammatory cytokines (IL-1β, IL-6 and TNF-α) and Toll-like receptors (TLR3 and TLR4) was assessed. In the two distinct mouse models analysed, the transcriptional activity of the ERV families was significant higher in comparison with corresponding controls, in whole embryos, blood and brain samples. Also the expression levels of the proinflammatory cytokines and TLRs were significantly higher than controls. Current results are in agreement with our previous findings in ASD children, supporting the hypothesis that ERVs may serve as biomarkers of atypical brain development. Moreover, the changes in ERVs and proinflammatory cytokines expression could be related with the autistic-like traits acquisition in the two mouse models.
Collapse
|
26
|
Gjelstrup MC, Stilund M, Petersen T, Møller HJ, Petersen EL, Christensen T. Subsets of activated monocytes and markers of inflammation in incipient and progressed multiple sclerosis. Immunol Cell Biol 2017; 96:160-174. [PMID: 29363161 PMCID: PMC5836924 DOI: 10.1111/imcb.1025] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 09/14/2017] [Accepted: 10/10/2017] [Indexed: 12/26/2022]
Abstract
Multiple sclerosis (MS) is an immune mediated, inflammatory and demyelinating disease of the central nervous system (CNS). Substantial evidence points toward monocytes and macrophages playing prominent roles early in disease, mediating both pro- and anti-inflammatory responses. Monocytes are subdivided into three subsets depending on the expression of CD14 and CD16, representing different stages of inflammatory activation. To investigate their involvement in MS, peripheral blood mononuclear cells from 40 patients with incipient or progressed MS and 20 healthy controls were characterized ex vivo. In MS samples, we demonstrate a highly significant increase in nonclassical monocytes (CD14+CD16++), with a concomitant significant reduction in classical monocytes (CD14++CD16-) compared with healthy controls. Also, a significant reduction in the surface expression of CD40, CD163, and CD192 was found, attributable to the upregulation of the nonclassical monocytes. In addition, significantly increased levels of human endogenous retrovirus (HERV) envelope (Env) epitopes, encoded by both HERV-H/F and HERV-W, were specifically found on nonclassical monocytes from patients with MS; emphasizing their involvement in MS disease. In parallel, serum and cerebrospinal fluid (CSF) samples were analyzed for soluble biomarkers of inflammation and neurodegeneration. For sCD163 versus CD163, no significant correlations were found, whereas highly significant correlations between levels of soluble neopterine and the intermediate monocyte (CD14++CD16+) population was found, as were correlations between levels of soluble osteopontin and the HERV Env expression on nonclassical monocytes. The results from this study emphasize the relevance of further focus on monocyte subsets, particularly the nonclassical monocytes in monitoring of inflammatory diseases.
Collapse
Affiliation(s)
- Mikkel Carstensen Gjelstrup
- Department of Biomedicine, Aarhus University, Bartholin Building, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark
| | - Morten Stilund
- Department of Biomedicine, Aarhus University, Bartholin Building, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark.,Department of Neurology, Aarhus University Hospital, Nørrebrogade 44, DK-8000, Aarhus C, Denmark
| | - Thor Petersen
- Department of Neurology, Aarhus University Hospital, Nørrebrogade 44, DK-8000, Aarhus C, Denmark
| | - Holger Jon Møller
- Department of Clinical Biochemistry, Aarhus University Hospital, Palle Juul Jensens Boulevard 99, DK-8200, Aarhus N, Denmark
| | - Eva Lykke Petersen
- Department of Biomedicine, Aarhus University, Bartholin Building, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark
| | - Tove Christensen
- Department of Biomedicine, Aarhus University, Bartholin Building, Wilhelm Meyers Allé 4, DK-8000, Aarhus C, Denmark
| |
Collapse
|
27
|
Ramamurthy M, Sankar S, Kannangai R, Nandagopal B, Sridharan G. Application of viromics: a new approach to the understanding of viral infections in humans. Virusdisease 2017; 28:349-359. [PMID: 29291225 DOI: 10.1007/s13337-017-0415-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 11/17/2017] [Indexed: 12/19/2022] Open
Abstract
This review is focused at exploring the strengths of modern technology driven data compiled in the areas of virus gene sequencing, virus protein structures and their implication to viral diagnosis and therapy. The information for virome analysis (viromics) is generated by the study of viral genomes (entire nucleotide sequence) and viral genes (coding for protein). Presently, the study of viral infectious diseases in terms of etiopathogenesis and development of newer therapeutics is undergoing rapid changes. Currently, viromics relies on deep sequencing, next generation sequencing (NGS) data and public domain databases like GenBank and unique virus specific databases. Two commonly used NGS platforms: Illumina and Ion Torrent, recommend maximum fragment lengths of about 300 and 400 nucleotides for analysis respectively. Direct detection of viruses in clinical samples is now evolving using these methods. Presently, there are a considerable number of good treatment options for HBV/HIV/HCV. These viruses however show development of drug resistance. The drug susceptibility regions of the genomes are sequenced and the prediction of drug resistance is now possible from 3 public domains available on the web. This has been made possible through advances in the technology with the advent of high throughput sequencing and meta-analysis through sophisticated and easy to use software and the use of high speed computers for bioinformatics. More recently NGS technology has been improved with single-molecule real-time sequencing. Here complete long reads can be obtained with less error overcoming a limitation of the NGS which is inherently prone to software anomalies that arise in the hands of personnel without adequate training. The development in understanding the viruses in terms of their genome, pathobiology, transcriptomics and molecular epidemiology constitutes viromics. It could be stated that these developments will bring about radical changes and advancement especially in the field of antiviral therapy and diagnostic virology.
Collapse
Affiliation(s)
- Mageshbabu Ramamurthy
- Sri Sakthi Amma Institute of Biomedical Research, Sri Narayani Hospital and Research Centre, Sripuram, Vellore, Tamil Nadu 632 055 India
| | - Sathish Sankar
- Sri Sakthi Amma Institute of Biomedical Research, Sri Narayani Hospital and Research Centre, Sripuram, Vellore, Tamil Nadu 632 055 India
| | - Rajesh Kannangai
- Department of Clinical Virology, Christian Medical College and Hospital, Vellore, Tamil Nadu 632 004 India
| | - Balaji Nandagopal
- Sri Sakthi Amma Institute of Biomedical Research, Sri Narayani Hospital and Research Centre, Sripuram, Vellore, Tamil Nadu 632 055 India
| | - Gopalan Sridharan
- Sri Sakthi Amma Institute of Biomedical Research, Sri Narayani Hospital and Research Centre, Sripuram, Vellore, Tamil Nadu 632 055 India
| |
Collapse
|
28
|
Mentis AFA, Dardiotis E, Grigoriadis N, Petinaki E, Hadjigeorgiou GM. Viruses and endogenous retroviruses in multiple sclerosis: From correlation to causation. Acta Neurol Scand 2017; 136:606-616. [PMID: 28542724 PMCID: PMC7159535 DOI: 10.1111/ane.12775] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2017] [Indexed: 12/28/2022]
Abstract
Multiple sclerosis is an immune-mediated disease with an environmental component. According to a long-standing but unproven hypothesis dating to initial descriptions of multiple sclerosis (MS) at the end of the 19th century, viruses are either directly or indirectly implicated in MS pathogenesis. Whether viruses in MS are principally causal or simply contributory remains to be proven, but many viruses or viral elements-predominantly Epstein-Barr virus, human endogenous retroviruses (HERVs) and human herpesvirus 6 (HHV-6) but also less common viruses such as Saffold and measles viruses-are associated with MS. Here, we present an up-to-date and comprehensive review of the main candidate viruses implicated in MS pathogenesis and summarize how these viruses might cause or lead to the hallmark demyelinating and inflammatory lesions of MS. We review data from epidemiological, animal and in vitro studies and in doing so offer a transdisciplinary approach to the topic. We argue that it is crucially important not to interpret "absence of evidence" as "evidence of absence" and that future studies need to focus on distinguishing correlative from causative associations. Progress in the MS-virus field is expected to arise from an increasing body of knowledge on the interplay between viruses and HERVs in MS. Such interactions suggest common HERV-mediated pathways downstream of viral infection that cause both neuroinflammation and neurodegeneration. We also comment on the limitations of existing studies and provide future research directions for the field.
Collapse
Affiliation(s)
- A.-F. A. Mentis
- Department of Microbiology; University Hospital of Larissa; University of Thessaly; Larissa Greece
- The Johns Hopkins University, AAP; Baltimore MD USA
| | - E. Dardiotis
- Department of Neurology; University Hospital of Larissa; University of Thessaly; Larissa Greece
| | - N. Grigoriadis
- Laboratory of Experimental Neurology and Neuroimmunology; B’ Department of Neurology; AHEPA University Hospital; Aristotle University of Thessaloniki; Thessaloniki Greece
| | - E. Petinaki
- Department of Microbiology; University Hospital of Larissa; University of Thessaly; Larissa Greece
| | - G. M. Hadjigeorgiou
- Department of Neurology; University Hospital of Larissa; University of Thessaly; Larissa Greece
| |
Collapse
|
29
|
Brattås PL, Jönsson ME, Fasching L, Nelander Wahlestedt J, Shahsavani M, Falk R, Falk A, Jern P, Parmar M, Jakobsson J. TRIM28 Controls a Gene Regulatory Network Based on Endogenous Retroviruses in Human Neural Progenitor Cells. Cell Rep 2017; 18:1-11. [PMID: 28052240 DOI: 10.1016/j.celrep.2016.12.010] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 10/26/2016] [Accepted: 12/02/2016] [Indexed: 11/30/2022] Open
Abstract
Endogenous retroviruses (ERVs), which make up 8% of the human genome, have been proposed to participate in the control of gene regulatory networks. In this study, we find a region- and developmental stage-specific expression pattern of ERVs in the developing human brain, which is linked to a transcriptional network based on ERVs. We demonstrate that almost 10,000, primarily primate-specific, ERVs act as docking platforms for the co-repressor protein TRIM28 in human neural progenitor cells, which results in the establishment of local heterochromatin. Thereby, TRIM28 represses ERVs and consequently regulates the expression of neighboring genes. These results uncover a gene regulatory network based on ERVs that participates in control of gene expression of protein-coding transcripts important for brain development.
Collapse
Affiliation(s)
- Per Ludvik Brattås
- Laboratory of Molecular Neurogenetics, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, BMC A11, Lund University, 221 84 Lund, Sweden
| | - Marie E Jönsson
- Laboratory of Molecular Neurogenetics, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, BMC A11, Lund University, 221 84 Lund, Sweden
| | - Liana Fasching
- Laboratory of Molecular Neurogenetics, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, BMC A11, Lund University, 221 84 Lund, Sweden
| | - Jenny Nelander Wahlestedt
- Developmental and Regenerative Neurobiology, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, BMC A11, Lund University, 221 84 Lund, Sweden
| | - Mansoureh Shahsavani
- Department of Neuroscience, Karolinska Institute, Retziusväg 8, 171 77 Stockholm, Sweden
| | - Ronny Falk
- Department of Neuroscience, Karolinska Institute, Retziusväg 8, 171 77 Stockholm, Sweden
| | - Anna Falk
- Department of Neuroscience, Karolinska Institute, Retziusväg 8, 171 77 Stockholm, Sweden
| | - Patric Jern
- Science for Life Laboratory, Department of Medical Biochemistry and Microbiology, Uppsala University, 751 23 Uppsala, Sweden
| | - Malin Parmar
- Developmental and Regenerative Neurobiology, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, BMC A11, Lund University, 221 84 Lund, Sweden
| | - Johan Jakobsson
- Laboratory of Molecular Neurogenetics, Department of Experimental Medical Science, Wallenberg Neuroscience Center and Lund Stem Cell Center, BMC A11, Lund University, 221 84 Lund, Sweden.
| |
Collapse
|
30
|
Christensen T. Human endogenous retroviruses in the aetiology of MS. Acta Neurol Scand 2017; 136 Suppl 201:18-21. [PMID: 29068488 DOI: 10.1111/ane.12836] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2017] [Indexed: 12/25/2022]
Abstract
Several lines of investigation have provided strong indications for an association between the immune-mediated, neurologic disease multiple sclerosis (MS) and human endogenous retroviruses (HERVs). Whether the relationship is causal is yet to be established. Endogenous retroviruses are pathogenic-in other species than the human. Several aspects of the activation and involvement of specific HERV families (HERV-H/F and HERV-W/MSRV) have been documented, both for cells in the periphery and in the central nervous system. Specific HERV-encoded genes and certain gene products (envelope proteins, Envs) appear strongly associated with the disease and have pathogenic potential. Most HERV sequences are non-functional, whereas some HERV loci have coding potential but remain quiescent in non-pathological conditions, so the importance of regulatory pathways and epigenetics involved in regulating HERV activation, de-repression, and also involvement of retroviral restriction factors, is emerging. Disease intervention by means of antiretrovirals has potential as a novel therapeutic strategy in MS treatment; this is compounded by the apparently reduced risk of MS in HIV infection as a consequence of therapy. Extensive studies of HERVs, their role in neurologic diseases, and their potential as therapeutic targets are needed.
Collapse
Affiliation(s)
- T. Christensen
- Department of Biomedicine; Aarhus University; Aarhus Denmark
| |
Collapse
|
31
|
Douville RN, Nath A. Human Endogenous Retrovirus-K and TDP-43 Expression Bridges ALS and HIV Neuropathology. Front Microbiol 2017; 8:1986. [PMID: 29075249 PMCID: PMC5641584 DOI: 10.3389/fmicb.2017.01986] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 09/27/2017] [Indexed: 12/12/2022] Open
Abstract
Despite the repetitive association of endogenous retroviruses in human disease, the mechanisms behind their pathological contributions remain to be resolved. Here we discuss how neuronal human endogenous retrovirus-K (HERV-K) expression in human immunodeficiency virus (HIV)-infected individuals is a distinct pathological aspect of HIV-associated neurological conditions, such as HIV encephalitis and HIV-associated neurocognitive disorders. Enhanced neuronal HERV-K levels were observed in the majority of HIV-infected individuals, and to a higher degree in brain tissue marked by HIV replication. Moreover, we highlight an important neuropathological overlap between amyotrophic lateral sclerosis and HIV encephalitis, that being the formation of neurotoxic TDP-43 deposits in neurons. Herein, we argue for enhanced transdisciplinary research in the field of ERV biology, using an example of how HERV-K expression has novel mechanistic and therapeutic implications for HIV neuropathology.
Collapse
Affiliation(s)
- Renée N Douville
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada.,Department of Immunology, University of Manitoba, Winnipeg, MB, Canada
| | - Avindra Nath
- Section of Infections of the Nervous System, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, MD, United States
| |
Collapse
|
32
|
Retroviral envelope proteins: Involvement in neuropathogenesis. J Neurol Sci 2017; 380:151-163. [DOI: 10.1016/j.jns.2017.07.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 06/23/2017] [Accepted: 07/18/2017] [Indexed: 02/07/2023]
|
33
|
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
|
34
|
Filiano AJ, Gadani SP, Kipnis J. How and why do T cells and their derived cytokines affect the injured and healthy brain? Nat Rev Neurosci 2017; 18:375-384. [PMID: 28446786 PMCID: PMC5823005 DOI: 10.1038/nrn.2017.39] [Citation(s) in RCA: 144] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The evolution of adaptive immunity provides enhanced defence against specific pathogens, as well as homeostatic immune surveillance of all tissues. Despite being 'immune privileged', the CNS uses the assistance of the immune system in physiological and pathological states. In this Opinion article, we discuss the influence of adaptive immunity on recovery after CNS injury and on cognitive and social brain function. We further extend a hypothesis that the pro-social effects of interferon-regulated genes were initially exploited by pathogens to increase host-host transmission, and that these genes were later recycled by the host to form part of an immune defence programme. In this way, the evolution of adaptive immunity may reflect a host-pathogen 'arms race'.
Collapse
Affiliation(s)
- Anthony J Filiano
- Center for Brain Immunology and Glia, Department of Neuroscience, School of Medicine, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Sachin P Gadani
- Center for Brain Immunology and Glia, Department of Neuroscience, School of Medicine, University of Virginia, Charlottesville, Virginia 22908, USA
| | - Jonathan Kipnis
- Center for Brain Immunology and Glia, Department of Neuroscience, School of Medicine, University of Virginia, Charlottesville, Virginia 22908, USA
| |
Collapse
|
35
|
Uleri E, Piu C, Caocci M, Ibba G, Serra C, Dolei A. The EGF epidermal growth factor counteracts Tat modulation of human endogenous retroviruses of the W family in astrocytes. J Neurovirol 2017; 23:587-592. [DOI: 10.1007/s13365-017-0531-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/10/2017] [Accepted: 04/21/2017] [Indexed: 01/26/2023]
|
36
|
Meyer TJ, Rosenkrantz JL, Carbone L, Chavez SL. Endogenous Retroviruses: With Us and against Us. Front Chem 2017; 5:23. [PMID: 28439515 PMCID: PMC5384584 DOI: 10.3389/fchem.2017.00023] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2016] [Accepted: 03/20/2017] [Indexed: 12/13/2022] Open
Abstract
Mammalian genomes are scattered with thousands of copies of endogenous retroviruses (ERVs), mobile genetic elements that are relics of ancient retroviral infections. After inserting copies into the germ line of a host, most ERVs accumulate mutations that prevent the normal assembly of infectious viral particles, becoming trapped in host genomes and unable to leave to infect other cells. While most copies of ERVs are inactive, some are transcribed and encode the proteins needed to generate new insertions at novel loci. In some cases, old copies are removed via recombination and other mechanisms. This creates a shifting landscape of ERV copies within host genomes. New insertions can disrupt normal expression of nearby genes via directly inserting into key regulatory elements or by containing regulatory motifs within their sequences. Further, the transcriptional silencing of ERVs via epigenetic modification may result in changes to the epigenetic regulation of adjacent genes. In these ways, ERVs can be potent sources of regulatory disruption as well as genetic innovation. Here, we provide a brief review of the association between ERVs and gene expression, especially as observed in pre-implantation development and placentation. Moreover, we will describe how disruption of the regulated mechanisms of ERVs may impact somatic tissues, mostly in the context of human disease, including cancer, neurodegenerative disorders, and schizophrenia. Lastly, we discuss the recent discovery that some ERVs may have been pressed into the service of their host genomes to aid in the innate immune response to exogenous viral infections.
Collapse
Affiliation(s)
- Thomas J Meyer
- Division of Bioinformatics and Computational Biology, Department of Medical Informatics and Clinical Epidemiology, Oregon Health & Science UniversityPortland, OR, USA
| | - Jimi L Rosenkrantz
- Department of Molecular and Medical Genetics, Oregon Health & Science UniversityPortland, OR, USA.,Division of Reproductive & Developmental Sciences, Oregon National Primate Research CenterPortland, OR, USA
| | - Lucia Carbone
- Division of Bioinformatics and Computational Biology, Department of Medical Informatics and Clinical Epidemiology, Oregon Health & Science UniversityPortland, OR, USA.,Department of Molecular and Medical Genetics, Oregon Health & Science UniversityPortland, OR, USA.,Department of Medicine, Knight Cardiovascular Institute, Oregon Health & Science UniversityPortland, OR, USA
| | - Shawn L Chavez
- Division of Reproductive & Developmental Sciences, Oregon National Primate Research CenterPortland, OR, USA.,Departments of Obstetrics and Gynecology and Physiology and Pharmacology, Oregon Health & Science University School of MedicinePortland, OR, USA
| |
Collapse
|
37
|
Wolff F, Leisch M, Greil R, Risch A, Pleyer L. The double-edged sword of (re)expression of genes by hypomethylating agents: from viral mimicry to exploitation as priming agents for targeted immune checkpoint modulation. Cell Commun Signal 2017; 15:13. [PMID: 28359286 PMCID: PMC5374693 DOI: 10.1186/s12964-017-0168-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 03/21/2017] [Indexed: 12/20/2022] Open
Abstract
Hypomethylating agents (HMAs) have been widely used over the last decade, approved for use in myelodysplastic syndrome (MDS), chronic myelomonocytic leukemia (CMML) and acute myeloid leukemia (AML). The proposed central mechanism of action of HMAs, is the reversal of aberrant methylation in tumor cells, thus reactivating CpG-island promoters and leading to (re)expression of tumor suppressor genes. Recent investigations into the mode of action of azacitidine (AZA) and decitabine (DAC) have revealed new molecular mechanisms that impinge on tumor immunity via induction of an interferon response, through activation of endogenous retroviral elements (ERVs) that are normally epigenetically silenced. Although the global demethylation of DNA by HMAs can induce anti-tumor effects, it can also upregulate the expression of inhibitory immune checkpoint receptors and their ligands, resulting in secondary resistance to HMAs. Recent studies have, however, suggested that this could be exploited to prime or (re)sensitize tumors to immune checkpoint inhibitor therapies. In recent years, immune checkpoints have been targeted by novel therapies, with the aim of (re)activating the host immune system to specifically eliminate malignant cells. Antibodies blocking checkpoint receptors have been FDA-approved for some solid tumors and a plethora of clinical trials testing these and other checkpoint inhibitors are under way. This review will discuss AZA and DAC novel mechanisms of action resulting from the re-expression of pathologically hypermethylated promoters of gene sets that are related to interferon signaling, antigen presentation and inflammation. We also review new insights into the molecular mechanisms of action of transient, low-dose HMAs on various tumor types and discuss the potential of new treatment options and combinations.
Collapse
Affiliation(s)
- Florian Wolff
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria
| | - Michael Leisch
- 3rd Medical Department with Hematology and Medical Oncology, Hemostaseology, Rheumatology and Infectious Diseases, Laboratory for Immunological and Molecular Cancer Research, Oncologic Center, Paracelsus Medical University Salzburg, Müllner Hauptstraße 48, A-5020, Salzburg, Austria
| | - Richard Greil
- 3rd Medical Department with Hematology and Medical Oncology, Hemostaseology, Rheumatology and Infectious Diseases, Laboratory for Immunological and Molecular Cancer Research, Oncologic Center, Paracelsus Medical University Salzburg, Müllner Hauptstraße 48, A-5020, Salzburg, Austria.,Salzburg Cancer Research Institute - Center for Clinical Cancer and Immunology Trials, Salzburg, Austria.,Cancer Cluster Salzburg, Salzburg, Austria
| | - Angela Risch
- Department of Molecular Biology, University of Salzburg, Salzburg, Austria.,Cancer Cluster Salzburg, Salzburg, Austria
| | - Lisa Pleyer
- 3rd Medical Department with Hematology and Medical Oncology, Hemostaseology, Rheumatology and Infectious Diseases, Laboratory for Immunological and Molecular Cancer Research, Oncologic Center, Paracelsus Medical University Salzburg, Müllner Hauptstraße 48, A-5020, Salzburg, Austria. .,Salzburg Cancer Research Institute - Center for Clinical Cancer and Immunology Trials, Salzburg, Austria. .,Cancer Cluster Salzburg, Salzburg, Austria.
| |
Collapse
|
38
|
Martinez A, Palomo Ruiz MDV, Perez DI, Gil C. Drugs in clinical development for the treatment of amyotrophic lateral sclerosis. Expert Opin Investig Drugs 2017; 26:403-414. [PMID: 28277881 DOI: 10.1080/13543784.2017.1302426] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Amyotrophic Lateral Sclerosis (ALS) is a fatal motor neuron progressive disorder for which no treatment exists to date. However, there are other investigational drugs and therapies currently under clinical development may offer hope in the near future. Areas covered: We have reviewed all the ALS ongoing clinical trials (until November 2016) and collected in Clinicaltrials.gov or EudraCT. We have described them in a comprehensive way and have grouped them in the following sections: biomarkers, biological therapies, cell therapy, drug repurposing and new drugs. Expert opinion: Despite multiple obstacles that explain the absence of effective drugs for the treatment of ALS, joint efforts among patient's associations, public and private sectors have fueled innovative research in this field, resulting in several compounds that are in the late stages of clinical trials. Drug repositioning is also playing an important role, having achieved the approval of some orphan drug applications, in late phases of clinical development. Endaravone has been recently approved in Japan and is pending in USA.
Collapse
Affiliation(s)
- Ana Martinez
- a IPSBB Unit , Centro de Investigaciones Biologicas-CSIC , Madrid , Spain
| | | | - Daniel I Perez
- a IPSBB Unit , Centro de Investigaciones Biologicas-CSIC , Madrid , Spain
| | - Carmen Gil
- a IPSBB Unit , Centro de Investigaciones Biologicas-CSIC , Madrid , Spain
| |
Collapse
|
39
|
Abstract
Infections of the nervous system are an important and challenging aspect of clinical neurology. Immediate correct diagnosis enables to introduce effective therapy, in conditions that without diagnosis may leave the patient with severe neurological incapacitation and sometimes even death. The cerebrospinal fluid (CSF) is a mirror that reflects nervous system pathology and can promote early diagnosis and therapy. The present chapter focuses on the CSF findings in neuro-infections, mainly viral and bacterial. Opening pressure, protein and glucose levels, presence of cells and type of the cellular reaction should be monitored. Other tests can also shed light on the causative agent: serology, culture, staining, molecular techniques such as polymerase chain reaction. Specific examination such as panbacterial and panfungal examinations should be examined when relevant. Our chapter is a guide-text that combines clinical presentation and course with CSF findings as a usuaful tool in diagnosis of neuroinfections.
Collapse
Affiliation(s)
- Felix Benninger
- Department of Neurology, Rabin Medical Center, Petach Tikva, Israel
| | - Israel Steiner
- Department of Neurology, Rabin Medical Center, Petach Tikva, Israel
| |
Collapse
|
40
|
Martin GM. Geroscience: Addressing the mismatch between its exciting research opportunities, its economic imperative and its current funding crisis. Exp Gerontol 2016; 94:46-51. [PMID: 27871822 DOI: 10.1016/j.exger.2016.11.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 11/14/2016] [Accepted: 11/16/2016] [Indexed: 12/11/2022]
Abstract
There is at present a huge disconnect between levels of funding for basic research on fundamental mechanisms of biological aging and, given demographic projections, the anticipated enormous social and economic impacts of a litany of chronic diseases for which aging is by far the major risk factor: One valuable approach, recently instigated by Felipe Sierra & colleagues at the US National Institute on Aging, is the development of a Geroscience Interest Group among virtually all of the NIH institutes. A complementary approach would be to seek major escalations of private funding. The American Federation for Aging Research, the Paul Glenn Foundation and the Ellison Medical Foundation pioneered efforts by the private sector to provide substantial supplements to public sources of funding. It is time for our community to organize efforts towards the enhancements of such crucial contributions, especially in support of the emerging generation of young investigators, many of whom are leaving our ranks to seek alternative employment. To do so, we must provide potential donors with strong economic, humanitarian and scientific rationales. An initial approach to such efforts is briefly outlined in this manuscript as a basis for wider discussions within our community.
Collapse
Affiliation(s)
- George M Martin
- Department of Pathology, University of Washington, Seattle, WA 98195, USA; Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| |
Collapse
|
41
|
Activation of endogenous human stem cell-associated retroviruses (SCARs) and therapy-resistant phenotypes of malignant tumors. Cancer Lett 2016; 376:347-59. [PMID: 27084523 DOI: 10.1016/j.canlet.2016.04.014] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 04/08/2016] [Accepted: 04/10/2016] [Indexed: 02/04/2023]
Abstract
Recent reports revealed consistent activation of specific endogenous retroviral elements in human preimplantation embryos and embryonic stem cells. Activity of stem cell associated retroviruses (SCARs) has been implicated in seeding thousands of human-specific regulatory sequences in the hESC genome. Activation of specific SCARs has been demonstrated in patients diagnosed with multiple types of cancer, autoimmune diseases, and neurodegenerative disorders, and appears associated with clinically lethal therapy resistant death-from-cancer phenotypes in a sub-set of cancer patients diagnosed with different types of malignant tumors. A hallmark feature of human-specific SCAR integration sites is deletions of ancestral DNA. Analysis of human-specific genetic loci of SCARs' stemness networks in tumor samples of TCGA cohorts representing 29 cancer types suggests that this approach may facilitate identification of pan-cancer genomic signatures of clinically-lethal disease defined by the presence of somatic non-silent mutations, gene-level copy number changes, and transcripts and proteins' expression of SCAR-regulated host genes. Present analyses indicate that multiple lines of strong circumstantial evidence support the hypothesis that activation of SCARs' networks may play an important role in cancer progression and metastasis, perhaps contributing to the emergence of clinically-lethal therapy-resistant death-from-cancer phenotypes.
Collapse
|