1
|
Garcia-Montojo M, Fathi S, Rastegar C, Simula ER, Doucet-O'Hare T, Cheng YHH, Abrams RPM, Pasternack N, Malik N, Bachani M, Disanza B, Maric D, Lee MH, Wang H, Santamaria U, Li W, Sampson K, Lorenzo JR, Sanchez IE, Mezghrani A, Li Y, Sechi LA, Pineda S, Heiman M, Kellis M, Steiner J, Nath A. TDP-43 proteinopathy in ALS is triggered by loss of ASRGL1 and associated with HML-2 expression. Nat Commun 2024; 15:4163. [PMID: 38755145 PMCID: PMC11099023 DOI: 10.1038/s41467-024-48488-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 05/02/2024] [Indexed: 05/18/2024] Open
Abstract
TAR DNA-binding protein 43 (TDP-43) proteinopathy in brain cells is the hallmark of amyotrophic lateral sclerosis (ALS) but its cause remains elusive. Asparaginase-like-1 protein (ASRGL1) cleaves isoaspartates, which alter protein folding and susceptibility to proteolysis. ASRGL1 gene harbors a copy of the human endogenous retrovirus HML-2, whose overexpression contributes to ALS pathogenesis. Here we show that ASRGL1 expression was diminished in ALS brain samples by RNA sequencing, immunohistochemistry, and western blotting. TDP-43 and ASRGL1 colocalized in neurons but, in the absence of ASRGL1, TDP-43 aggregated in the cytoplasm. TDP-43 was found to be prone to isoaspartate formation and a substrate for ASRGL1. ASRGL1 silencing triggered accumulation of misfolded, fragmented, phosphorylated and mislocalized TDP-43 in cultured neurons and motor cortex of female mice. Overexpression of ASRGL1 restored neuronal viability. Overexpression of HML-2 led to ASRGL1 silencing. Loss of ASRGL1 leading to TDP-43 aggregation may be a critical mechanism in ALS pathophysiology.
Collapse
Affiliation(s)
- Marta Garcia-Montojo
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Saeed Fathi
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Cyrus Rastegar
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Elena Rita Simula
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
- Struttura Complessa Microbiologia e Virologia, Azienda Ospedaliera Universitaria Sassari, Sassari, Italy
| | - Tara Doucet-O'Hare
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Y H Hank Cheng
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Rachel P M Abrams
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Nicholas Pasternack
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Nasir Malik
- Translational Neuroscience Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Muzna Bachani
- Translational Neuroscience Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Brianna Disanza
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Dragan Maric
- Flow and Imaging Cytometry Core Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Myoung-Hwa Lee
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Herui Wang
- Neuro-Oncology Branch, National Cancer Institute (NIH), Bethesda, MD, USA
| | - Ulisses Santamaria
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Wenxue Li
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Kevon Sampson
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Juan Ramiro Lorenzo
- Centro de Investigación Veterinaria de Tandil (CIVETAN), CONICET-CICPBA-UNCPBA, Facultad de Ciencias Veterinarias, Universidad Nacional del Centro (FCV-UNCPBA), Tandil, Argentina
| | - Ignacio E Sanchez
- Protein Physiology Laboratory, Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales and IQUIBICEN-CONICET, Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Alexandre Mezghrani
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
- Centre de Biologie Structurale, Centre national de la recherche scientifique (CNRS), Montpellier, France
| | - Yan Li
- Protein/Peptide Sequencing Facility, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Leonardo Antonio Sechi
- Struttura Complessa Microbiologia e Virologia, Azienda Ospedaliera Universitaria Sassari, Sassari, Italy
| | | | - Myriam Heiman
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Manolis Kellis
- Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Joseph Steiner
- Translational Neuroscience Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA
| | - Avindra Nath
- Section of Infections of the Nervous System, National Institute of Neurological Disorders and Stroke, National Institutes of Health (NIH), Bethesda, MD, USA.
| |
Collapse
|
2
|
Liu S, Hong Y, Wang BR, Wei ZQ, Zhao HD, Jiang T, Zhang YD, Shi JQ. The presence and clinical significance of autoantibodies in amyotrophic lateral sclerosis: a narrative review. Neurol Sci 2024:10.1007/s10072-024-07581-x. [PMID: 38733435 DOI: 10.1007/s10072-024-07581-x] [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: 02/01/2024] [Accepted: 05/03/2024] [Indexed: 05/13/2024]
Abstract
Amyotrophic lateral sclerosis (ALS) is a debilitating and rapidly fatal neurodegenerative disease, which is characterized by the selective loss of the upper and lower motor neurons. The pathogenesis of ALS remains to be elucidated and has been connected to genetic, environmental and immune conditions. Evidence from clinical and experimental studies has suggested that the immune system played an important role in ALS pathophysiology. Autoantibodies are essential components of the immune system. Several autoantibodies directed at antigens associated with ALS pathogenesis have been identified in the serum and/or cerebrospinal fluid of ALS patients. The aim of this review is to summarize the presence and clinical significance of autoantibodies in ALS.
Collapse
Affiliation(s)
- Shen Liu
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, 210006, PR China
| | - Ye Hong
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, 210006, PR China
| | - Bian-Rong Wang
- Department of Neurology, Geriatric Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, 210006, PR China
| | - Zi-Qiao Wei
- The Second Clinical Medical School of Nanjing Medical University, Nanjing, Jiangsu Province, 211166, PR China
| | - Hong-Dong Zhao
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, 210006, PR China
| | - Teng Jiang
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, 210006, PR China
| | - Ying-Dong Zhang
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, 210006, PR China
| | - Jian-Quan Shi
- Department of Neurology, Nanjing First Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, 210006, PR China.
| |
Collapse
|
3
|
Dopkins N, Nixon DF. Activation of human endogenous retroviruses and its physiological consequences. Nat Rev Mol Cell Biol 2024; 25:212-222. [PMID: 37872387 DOI: 10.1038/s41580-023-00674-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2023] [Indexed: 10/25/2023]
Abstract
Human endogenous retroviruses (HERVs) are abundant sequences that persist within the human genome as remnants of ancient retroviral infections. These sequences became fixed and accumulate mutations or deletions over time. HERVs have affected human evolution and physiology by providing a unique repertoire of coding and non-coding sequences to the genome. In healthy individuals, HERVs participate in immune responses, formation of syncytiotrophoblasts and cell-fate specification. In this Review, we discuss how endogenized retroviral motifs and regulatory sequences have been co-opted into human physiology and how they are tightly regulated. Infections and mutations can derail this regulation, leading to differential HERV expression, which may contribute to pathologies including neurodegeneration, pathological inflammation and oncogenesis. Emerging evidence demonstrates that HERVs are crucial to human health and represent an understudied facet of many diseases, and we therefore argue that investigating their fundamental properties could improve existing therapies and help develop novel therapeutic strategies.
Collapse
Affiliation(s)
- Nicholas Dopkins
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, NY, USA.
| | - Douglas F Nixon
- Division of Infectious Diseases, Department of Medicine, Weill Cornell Medicine, New York, NY, USA.
| |
Collapse
|
4
|
Moreno-Martinez L, Macías-Redondo S, Strunk M, Guillén-Antonini MI, Lunetta C, Tarlarini C, Penco S, Calvo AC, Osta R, Schoorlemmer J. New Insights into Endogenous Retrovirus-K Transcripts in Amyotrophic Lateral Sclerosis. Int J Mol Sci 2024; 25:1549. [PMID: 38338823 PMCID: PMC10855536 DOI: 10.3390/ijms25031549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/12/2024] [Accepted: 01/22/2024] [Indexed: 02/12/2024] Open
Abstract
Retroviral reverse transcriptase activity and the increased expression of human endogenous retroviruses (HERVs) are associated with amyotrophic lateral sclerosis (ALS). We were interested in confirming HERVK overexpression in the ALS brain, its use as an accessory diagnostic marker for ALS, and its potential interplay with neuroinflammation. Using qPCR to analyze HERVK expression in peripheral blood mononuclear cells (PBMCs) and in postmortem brain samples from ALS patients, no significant differences were observed between patients and control subjects. By contrast, we report alterations in the expression patterns of specific HERVK copies, especially in the brainstem. Out of 27 HERVK copies sampled, the relative expression of 17 loci was >1.2-fold changed in samples from ALS patients. In particular, the relative expression of two HERVK copies (Chr3-3 and Chr3-5) was significantly different in brainstem samples from ALS patients compared with controls. Further qPCR analysis of inflammation markers in brain samples revealed a significant increase in NLRP3 levels, while TNFA, IL6, and GZMB showed slight decreases. We cannot confirm global HERVK overexpression in ALS, but we can report the ALS-specific overexpression of selected HERVK copies in the ALS brain. Our data are compatible with the requirement for better patient stratification and support the potential importance of particular HERVK copies in ALS.
Collapse
Affiliation(s)
- Laura Moreno-Martinez
- Laboratory of Genetics and Biochemistry (LAGENBIO), Faculty of Veterinary, University of Zaragoza, Miguel Servet 177, 50013 Zaragoza, Spain; (L.M.-M.); (R.O.)
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, Instituto de Salud Carlos III (CIBER-CIBERNED-ISCIII), 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain
- Instituto Agroalimentario de Aragón (IA2), University of Zaragoza-CITA, C/Miguel, Servet 177, 50013 Zaragoza, Spain
| | - Sofía Macías-Redondo
- Instituto Aragonés de Ciencias de la Salud (IACS), Centro de Investigación Biomédica de Aragón (CIBA), 50009 Zaragoza, Spain; (S.M.-R.)
| | - Mark Strunk
- Instituto Aragonés de Ciencias de la Salud (IACS), Centro de Investigación Biomédica de Aragón (CIBA), 50009 Zaragoza, Spain; (S.M.-R.)
| | | | - Christian Lunetta
- NEMO (NEuroMuscular Omnicentre) Clinical Center, Fondazione Serena Onlus, 20162 Milan, Italy
- Neurorehabilitation Department of Milano Institute, Istituti Clinici Scientifici Maugeri IRCCS, 20138 Milan, Italy
- Medical Genetics Unit, Department of Laboratory Medicine, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milan, Italy; (C.T.)
| | - Claudia Tarlarini
- Medical Genetics Unit, Department of Laboratory Medicine, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milan, Italy; (C.T.)
| | - Silvana Penco
- Medical Genetics Unit, Department of Laboratory Medicine, ASST Grande Ospedale Metropolitano Niguarda, 20162 Milan, Italy; (C.T.)
| | - Ana Cristina Calvo
- Laboratory of Genetics and Biochemistry (LAGENBIO), Faculty of Veterinary, University of Zaragoza, Miguel Servet 177, 50013 Zaragoza, Spain; (L.M.-M.); (R.O.)
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, Instituto de Salud Carlos III (CIBER-CIBERNED-ISCIII), 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain
- Instituto Agroalimentario de Aragón (IA2), University of Zaragoza-CITA, C/Miguel, Servet 177, 50013 Zaragoza, Spain
| | - Rosario Osta
- Laboratory of Genetics and Biochemistry (LAGENBIO), Faculty of Veterinary, University of Zaragoza, Miguel Servet 177, 50013 Zaragoza, Spain; (L.M.-M.); (R.O.)
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas, Instituto de Salud Carlos III (CIBER-CIBERNED-ISCIII), 28029 Madrid, Spain
- Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain
- Instituto Agroalimentario de Aragón (IA2), University of Zaragoza-CITA, C/Miguel, Servet 177, 50013 Zaragoza, Spain
| | - Jon Schoorlemmer
- Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain
- Instituto Aragonés de Ciencias de la Salud (IACS), Centro de Investigación Biomédica de Aragón (CIBA), 50009 Zaragoza, Spain; (S.M.-R.)
- ARAID Foundation, 50009 Zaragoza, Spain
| |
Collapse
|
5
|
Simula ER, Zarbo IR, Arru G, Sechi E, Meloni R, Deiana GA, Solla P, Sechi LA. Antibody Response to HERV-K and HERV-W Envelope Epitopes in Patients with Myasthenia Gravis. Int J Mol Sci 2023; 25:446. [PMID: 38203616 PMCID: PMC10778599 DOI: 10.3390/ijms25010446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 12/20/2023] [Accepted: 12/25/2023] [Indexed: 01/12/2024] Open
Abstract
Myasthenia gravis is an antibody-mediated autoimmune neurological disorder characterized by impaired neuromuscular junction transmission, resulting in muscle weakness. Recently, the involvement of Human Endogenous Retroviruses (HERVs) in the pathophysiology of different immune-mediated and neurodegenerative diseases, such as multiple sclerosis, has been demonstrated. We aimed to investigate potential immune system involvement related to humoral responses targeting specific epitopes of HERV-K and HERV-W envelope proteins in myasthenia gravis. Myasthenia gravis patients were recruited in the Neurology Unit, while healthy controls were selected from the Blood Transfusion Center, both affiliated with AOU Sassari. Highly immunogenic antigens of HERV-K and HERV-W envelope proteins were identified using the Immune Epitope Database (IEDB) online tool. These epitopes were utilized in enzyme-linked immunosorbent assays (ELISA) to detect autoantibodies in serum directed against these sequences. The study involved 39 Healthy Donors and 47 MG patients, further categorized into subgroups based on the presence of autoantibodies: MG-AchR Ab+ (n = 17), MG-MuSK Ab+ (n = 7), double seronegative patients (MG-DSN, n = 18), MG-LRP4 Ab + (n = 4), and one patient with no antibodies data (n = 1). Our findings revealed high levels of autoantibodies in myasthenia gravis patients directed against the HERV-K-env-su(19-37), HERV-K-env-su(109-126), HERV-K-env-su(164-186), HERV-W-env(93-108), HERV-W-env(129-14), and HERV-W-env(248-262) epitopes. Notably, these results remained highly significant even when patients were subdivided into MG-AchR Ab+ and MG-DSN subgroups. Correlation analysis further revealed significant positive associations between the antibody levels against HERV-K and HERV-W families in patients, suggesting a synergistic action of the two HERVs in the pathology context since this correlation is absent in the control group. This study marks the first identification of a specific humoral response directed against defined epitopes of HERV-K and HERV-W envelope proteins in myasthenia gravis patients. These findings lay the foundation for future investigations aimed at elucidating the molecular mechanisms driving this immune response. The detection of these autoantibodies suggests the potential for novel biomarkers, especially within the MG-DSN patient subgroup, addressing the need for new biomarkers in this population.
Collapse
Affiliation(s)
- Elena Rita Simula
- Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43b, 07100 Sassari, Italy;
| | - Ignazio Roberto Zarbo
- Department of Medicine, Surgery and Pharmacy University of Sassari, Viale S. Pietro 10, 07100 Sassari, Italy; (I.R.Z.); (G.A.); (E.S.); (R.M.); (G.A.D.)
| | - Giannina Arru
- Department of Medicine, Surgery and Pharmacy University of Sassari, Viale S. Pietro 10, 07100 Sassari, Italy; (I.R.Z.); (G.A.); (E.S.); (R.M.); (G.A.D.)
| | - Elia Sechi
- Department of Medicine, Surgery and Pharmacy University of Sassari, Viale S. Pietro 10, 07100 Sassari, Italy; (I.R.Z.); (G.A.); (E.S.); (R.M.); (G.A.D.)
| | - Rossella Meloni
- Department of Medicine, Surgery and Pharmacy University of Sassari, Viale S. Pietro 10, 07100 Sassari, Italy; (I.R.Z.); (G.A.); (E.S.); (R.M.); (G.A.D.)
- Department of Medical Sciences and Public Health, University of Cagliari, 09124 Cagliari, Italy
| | - Giovanni Andrea Deiana
- Department of Medicine, Surgery and Pharmacy University of Sassari, Viale S. Pietro 10, 07100 Sassari, Italy; (I.R.Z.); (G.A.); (E.S.); (R.M.); (G.A.D.)
| | - Paolo Solla
- Department of Medicine, Surgery and Pharmacy University of Sassari, Viale S. Pietro 10, 07100 Sassari, Italy; (I.R.Z.); (G.A.); (E.S.); (R.M.); (G.A.D.)
| | - Leonardo Antonio Sechi
- Department of Biomedical Sciences, University of Sassari, Viale San Pietro 43b, 07100 Sassari, Italy;
- Struttura Complessa Microbiologia e Virologia, Azienda Ospedaliera Universitaria, 07100 Sassari, Italy
| |
Collapse
|
6
|
Shin W, Mun S, Han K. Human Endogenous Retrovirus-K (HML-2)-Related Genetic Variation: Human Genome Diversity and Disease. Genes (Basel) 2023; 14:2150. [PMID: 38136972 PMCID: PMC10742618 DOI: 10.3390/genes14122150] [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: 10/25/2023] [Revised: 11/23/2023] [Accepted: 11/26/2023] [Indexed: 12/24/2023] Open
Abstract
Human endogenous retroviruses (HERVs) comprise a significant portion of the human genome, making up roughly 8%, a notable comparison to the 2-3% represented by coding sequences. Numerous studies have underscored the critical role and importance of HERVs, highlighting their diverse and extensive influence on the evolution of the human genome and establishing their complex correlation with various diseases. Among HERVs, the HERV-K (HML-2) subfamily has recently attracted significant attention, integrating into the human genome after the divergence between humans and chimpanzees. Its insertion in the human genome has received considerable attention due to its structural and functional characteristics and the time of insertion. Originating from ancient exogenous retroviruses, these elements succeeded in infecting germ cells, enabling vertical transmission and existing as proviruses within the genome. Remarkably, these sequences have retained the capacity to form complete viral sequences, exhibiting activity in transcription and translation. The HERV-K (HML-2) subfamily is the subject of active debate about its potential positive or negative effects on human genome evolution and various pathologies. This review summarizes the variation, regulation, and diseases in human genome evolution arising from the influence of HERV-K (HML-2).
Collapse
Affiliation(s)
- Wonseok Shin
- NGS Clinical Laboratory, Division of Cancer Research, Dankook University Hospital, Cheonan 31116, Republic of Korea;
- Smart Animal Bio Institute, Dankook University, Cheonan 31116, Republic of Korea;
| | - Seyoung Mun
- Smart Animal Bio Institute, Dankook University, Cheonan 31116, Republic of Korea;
- College of Science & Technology, Dankook University, Cheonan 31116, Republic of Korea
- Center for Bio-Medical Engineering Core Facility, Dankook University, Cheonan 31116, Republic of Korea
| | - Kyudong Han
- Smart Animal Bio Institute, Dankook University, Cheonan 31116, Republic of Korea;
- Center for Bio-Medical Engineering Core Facility, Dankook University, Cheonan 31116, Republic of Korea
- Department of Microbiology, College of Science & Technology, Dankook University, Cheonan 31116, Republic of Korea
- Department of Bioconvergence Engineering, Dankook University, Yongin 16890, Republic of Korea
- R&D Center, HuNBiome Co., Ltd., Seoul 08507, Republic of Korea
| |
Collapse
|
7
|
Dubowsky M, Theunissen F, Carr JM, Rogers ML. The Molecular Link Between TDP-43, Endogenous Retroviruses and Inflammatory Neurodegeneration in Amyotrophic Lateral Sclerosis: a Potential Target for Triumeq, an Antiretroviral Therapy. Mol Neurobiol 2023; 60:6330-6345. [PMID: 37450244 PMCID: PMC10533598 DOI: 10.1007/s12035-023-03472-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 06/30/2023] [Indexed: 07/18/2023]
Abstract
Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND), is a progressive neurological disorder, characterised by the death of upper and lower motor neurons. The aetiology of ALS remains unknown, and treatment options are limited. Endogenous retroviruses (ERVs), specifically human endogenous retrovirus type K (HERV-K), have been proposed to be involved in the propagation of neurodegeneration in ALS. ERVs are genomic remnants of ancient viral infection events, with most being inactive and not retaining the capacity to encode a fully infectious virus. However, some ERVs retain the ability to be activated and transcribed, and ERV transcripts have been found to be elevated within the brain tissue of MND patients. A hallmark of ALS pathology is altered localisation of the transactive response (TAR) DNA binding protein 43 kDa (TDP-43), which is normally found within the nucleus of neuronal and glial cells and is involved in RNA regulation. In ALS, TDP-43 aggregates within the cytoplasm and facilitates neurodegeneration. The involvement of ERVs in ALS pathology is thought to occur through TDP-43 and neuroinflammatory mediators. In this review, the proposed involvement of TDP-43, HERV-K and immune regulators on the onset and progression of ALS will be discussed. Furthermore, the evidence supporting a therapy based on targeting ERVs in ALS will be reviewed.
Collapse
Affiliation(s)
- Megan Dubowsky
- College of Medicine and Public Health and Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia.
| | - Frances Theunissen
- Perron Institute for Neurological and Translational Science, Nedlands, WA, Australia
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Murdoch, WA, Australia
| | - Jillian M Carr
- College of Medicine and Public Health and Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia
| | - Mary-Louise Rogers
- College of Medicine and Public Health and Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia
| |
Collapse
|
8
|
Russ E, Mikhalkevich N, Iordanskiy S. Expression of Human Endogenous Retrovirus Group K (HERV-K) HML-2 Correlates with Immune Activation of Macrophages and Type I Interferon Response. Microbiol Spectr 2023; 11:e0443822. [PMID: 36861980 PMCID: PMC10100713 DOI: 10.1128/spectrum.04438-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 01/30/2023] [Indexed: 03/03/2023] Open
Abstract
Human endogenous retroviruses (HERVs) comprise about 8.3% of the human genome and are capable of producing RNA molecules that can be sensed by pattern recognition receptors, leading to the activation of innate immune response pathways. The HERV-K (HML-2) subgroup is the youngest HERV clade with the highest degree of coding competence. Its expression is associated with inflammation-related diseases. However, the precise HML-2 loci, stimuli, and signaling pathways involved in these associations are not well understood or defined. To elucidate HML-2 expression on a locus-specific level, we used the retroelement sequencing tools TEcount and Telescope to analyze publicly available transcriptome sequencing (RNA-seq) and chromatin immunoprecipitation (ChIP) sequencing data sets of macrophages treated with a wide range of agonists. We found that macrophage polarization significantly correlates with modulation of the expression of specific HML-2 proviral loci. Further analysis demonstrated that the provirus HERV-K102, located in an intergenic region of locus 1q22, constituted the majority of the HML-2 derived transcripts following pro-inflammatory (M1) polarization and was upregulated explicitly in response to interferon gamma (IFN-γ) signaling. We found that signal transducer and activator of transcription 1 and interferon regulatory factor 1 interact with a solo long terminal repeat (LTR) located upstream of HERV-K102, termed LTR12F, following IFN-γ signaling. Using reporter constructs, we demonstrated that LTR12F is critical for HERV-K102 upregulation by IFN-γ. In THP1-derived macrophages, knockdown of HML-2 or knockout of MAVS, an adaptor of RNA-sensing pathways, significantly downregulated genes containing interferon-stimulated response elements (ISREs) in their promoters, suggesting an intermediate role of HERV-K102 in the switch from IFN-γ signaling to the activation of type I interferon expression and, therefore, in a positive feedback loop to enhance pro-inflammatory signaling. IMPORTANCE The human endogenous retrovirus group K subgroup, HML-2, is known to be elevated in a long list of inflammation-associated diseases. However, a clear mechanism for HML-2 upregulation in response to inflammation has not been defined. In this study, we identify a provirus of the HML-2 subgroup, HERV-K102, which is significantly upregulated and constitutes the majority of the HML-2 derived transcripts in response to pro-inflammatory activation of macrophages. Moreover, we identify the mechanism of HERV-K102 upregulation and demonstrate that HML-2 expression enhances interferon-stimulated response element activation. We also demonstrate that this provirus is elevated in vivo and correlates with interferon gamma signaling activity in cutaneous leishmaniasis patients. This study provides key insights into the HML-2 subgroup and suggests that it may participate in enhancing pro-inflammatory signaling in macrophages and probably other immune cells.
Collapse
Affiliation(s)
- Eric Russ
- Department of Pharmacology & Molecular Therapeutics, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland, USA
- Graduate Program of Cellular and Molecular Biology, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| | - Natallia Mikhalkevich
- Department of Pharmacology & Molecular Therapeutics, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland, USA
| | - Sergey Iordanskiy
- Department of Pharmacology & Molecular Therapeutics, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
- Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA
| |
Collapse
|
9
|
Endogenous retroviruses and TDP-43 proteinopathy form a sustaining feedback driving intercellular spread of Drosophila neurodegeneration. Nat Commun 2023; 14:966. [PMID: 36810738 PMCID: PMC9944888 DOI: 10.1038/s41467-023-36649-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 02/09/2023] [Indexed: 02/23/2023] Open
Abstract
Inter-cellular movement of "prion-like" proteins is thought to explain propagation of neurodegeneration between cells. For example, propagation of abnormally phosphorylated cytoplasmic inclusions of TAR-DNA-Binding protein (TDP-43) is proposed to underlie progression of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). But unlike transmissible prion diseases, ALS and FTD are not infectious and injection of aggregated TDP-43 is not sufficient to cause disease. This suggests a missing component of a positive feedback necessary to sustain disease progression. We demonstrate that endogenous retrovirus (ERV) expression and TDP-43 proteinopathy are mutually reinforcing. Expression of either Drosophila mdg4-ERV (gypsy) or the human ERV, HERV-K (HML-2) are each sufficient to stimulate cytoplasmic aggregation of human TDP-43. Viral ERV transmission also triggers TDP-43 pathology in recipient cells that express physiological levels of TDP-43, whether they are in contact or at a distance. This mechanism potentially underlies the TDP-43 proteinopathy-caused neurodegenerative propagation through neuronal tissue.
Collapse
|
10
|
HERV-K Envelope Protein Induces Long-Lasting Production of Autoantibodies in T1DM Patients at Onset in Comparison to ZNT8 Autoantibodies. Pathogens 2022; 11:pathogens11101188. [PMID: 36297245 PMCID: PMC9607583 DOI: 10.3390/pathogens11101188] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/05/2022] Open
Abstract
Human endogenous retroviruses (HERVs) have been thought of as silent passengers within our genomes, but their reactivation has been linked with several autoimmune diseases, including type 1 diabetes (T1DM). In order to evaluate the potential role of HERVs, in addition to the recognized role of HERV-W, we focused on the debated role of the HERV-K family in T1DM. Therefore, we performed a serological evaluation of IgG antibodies against HERV-K Env epitope (HERV-K Env19−37) in comparison to an important β-cellular autoimmunity biomarker, ZnT8, from plasma samples of Sardinian children at the onset of T1DM, different T1DM groups (1−5 and 6−12 years since diagnosis), and healthy controls (HCs), by an indirect enzyme-linked immunosorbent assay (ELISA). A significant antibody response was observed against HERV-K Env19−37 (p < 0.0001) in T1DM patients compared to HCs, and significantly higher IgG responses were detected in the group at the onset compared to the other T1DM groups and HCs. Unlike the trend of the β-cellular autoimmunity autoantibodies, for HERV-K Env antibodies we observed positive values that persist over time up to 5 years since the onset of T1DM. Our results add new evidence about the presence of antibodies against HERV-K in T1DM, but further investigations are necessary to relate these results with the established role of HERVs, considering the contrasting results for HERV-K.
Collapse
|