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Bharadwaj S, Groza Y, Mierzwicka JM, Malý P. Current understanding on TREM-2 molecular biology and physiopathological functions. Int Immunopharmacol 2024; 134:112042. [PMID: 38703564 DOI: 10.1016/j.intimp.2024.112042] [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: 02/08/2024] [Revised: 04/05/2024] [Accepted: 04/05/2024] [Indexed: 05/06/2024]
Abstract
Triggering receptor expressed on myeloid cells 2 (TREM-2), a glycosylated receptor belonging to the immunoglobin superfamily and especially expressed in the myeloid cell lineage, is frequently explained as a reminiscent receptor for both adaptive and innate immunity regulation. TREM-2 is also acknowledged to influence NK cell differentiation via the PI3K and PLCγ signaling pathways, as well as the partial activation or direct inhibition of T cells. Additionally, TREM-2 overexpression is substantially linked to cell-specific functions, such as enhanced phagocytosis, reduced toll-like receptor (TLR)-mediated inflammatory cytokine production, increased transcription of anti-inflammatory cytokines, and reshaped T cell function. Whereas TREM-2-deficient cells exhibit diminished phagocytic function and enhanced proinflammatory cytokines production, proceeding to inflammatory injuries and an immunosuppressive environment for disease progression. Despite the growing literature supporting TREM-2+ cells in various diseases, such as neurodegenerative disorders and cancer, substantial facets of TREM-2-mediated signaling remain inadequately understood relevant to pathophysiology conditions. In this direction, herein, we have summarized the current knowledge on TREM-2 biology and cell-specific TREM-2 expression, particularly in the modulation of pivotal TREM-2-dependent functions under physiopathological conditions. Furthermore, molecular regulation and generic biological relevance of TREM-2 are also discussed, which might provide an alternative approach for preventing or reducing TREM-2-associated deformities. At last, we discussed the TREM-2 function in supporting an immunosuppressive cancer environment and as a potential drug target for cancer immunotherapy. Hence, summarized knowledge of TREM-2 might provide a window to overcome challenges in clinically effective therapies for TREM-2-induced diseases in humans.
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Affiliation(s)
- Shiv Bharadwaj
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Průmyslová 595, 252 50 Vestec, Czech Republic.
| | - Yaroslava Groza
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Průmyslová 595, 252 50 Vestec, Czech Republic
| | - Joanna M Mierzwicka
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Průmyslová 595, 252 50 Vestec, Czech Republic
| | - Petr Malý
- Laboratory of Ligand Engineering, Institute of Biotechnology of the Czech Academy of Sciences, BIOCEV Research Center, Průmyslová 595, 252 50 Vestec, Czech Republic.
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Ogonowski N, Santamaria-Garcia H, Baez S, Lopez A, Laserna A, Garcia-Cifuentes E, Ayala-Ramirez P, Zarante I, Suarez-Obando F, Reyes P, Kauffman M, Cochran N, Schulte M, Sirkis DW, Spina S, Yokoyama JS, Miller BL, Kosik KS, Matallana D, Ibáñez A. Frontotemporal dementia presentation in patients with heterozygous p.H157Y variant of TREM2. J Med Genet 2023; 60:894-904. [PMID: 36813542 PMCID: PMC10447405 DOI: 10.1136/jmg-2022-108627] [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: 08/09/2022] [Accepted: 02/06/2023] [Indexed: 02/24/2023]
Abstract
BACKGROUND The triggering receptor expressed on myeloid cell 2 (TREM2) is a major regulator of neuroinflammatory processes in neurodegeneration. To date, the p.H157Y variant of TREM2 has been reported only in patients with Alzheimer's disease. Here, we report three patients with frontotemporal dementia (FTD) from three unrelated families with heterozygous p.H157Y variant of TREM2: two patients from Colombian families (study 1) and a third Mexican origin case from the USA (study 2). METHODS To determine if the p.H157Y variant might be associated with a specific FTD presentation, we compared in each study the cases with age-matched, sex-matched and education-matched groups-a healthy control group (HC) and a group with FTD with neither TREM2 mutations nor family antecedents (Ng-FTD and Ng-FTD-MND). RESULTS The two Colombian cases presented with early behavioural changes, greater impairments in general cognition and executive function compared with both HC and Ng-FTD groups. These patients also exhibited brain atrophy in areas characteristic of FTD. Furthermore, TREM2 cases showed increased atrophy compared with Ng-FTD in frontal, temporal, parietal, precuneus, basal ganglia, parahippocampal/hippocampal and cerebellar regions. The Mexican case presented with FTD and motor neuron disease (MND), showing grey matter reduction in basal ganglia and thalamus, and extensive TDP-43 type B pathology. CONCLUSION In all TREM2 cases, multiple atrophy peaks overlapped with the maximum peaks of TREM2 gene expression in crucial brain regions including frontal, temporal, thalamic and basal ganglia areas. These results provide the first report of an FTD presentation potentially associated with the p.H157Y variant with exacerbated neurocognitive impairments.
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Affiliation(s)
- Natalia Ogonowski
- Latin American Institute for Brain Health (BrainLat), Universidad Adolfo Ibanez, Adolfo Ibanez University, Santiago, Chile, Santiago de Chile, Chile
| | - Hernando Santamaria-Garcia
- Global Brain Health Institute (GBHI), University California San Francisco (UCSF), San Francisco, California, USA
- Pontificia Universidad Javeriana. Ph.D Program of Neuroscience, Bogotá, Colombia
- Hospital Universitario San Ignacio. Centro de Memoria y Cognición Intellectus, Bogotá, Colombia
| | | | - Andrea Lopez
- Hospital Universitario de la Fundación Santa Fe de Bogotá, Bogota, Colombia
- Pontificia Universidad Javeriana, Bogotá, Colombia
| | - Andrés Laserna
- Pontificia Universidad Javeriana, Bogota, Colombia
- University of Rochester Medical Center. Department of Anesthesiology and Perioperative Medicine. of Anesthesiology and Perioperative Medicine, Rochester, NY, New York, USA
| | - Elkin Garcia-Cifuentes
- Pontificia Universidad Javeriana, Bogota, Colombia
- Hospital Universitario San Ignacio, Bogotá, Colombia
| | - Paola Ayala-Ramirez
- Human Genomics Institute, Pontificia Universidad Javeriana, Bogota, Colombia
| | | | | | - Pablo Reyes
- Pontificia Universidad Javeriana, Bogota, Colombia
| | - Marcelo Kauffman
- Hospital General de Agudos Jose Maria Ramos Mejia Consultorio y Laboratorio de Neurogenetica, Buenos Aires, Argentina
- Universidad Austral. IIMT-FCB. Conicet, Buenos Aires, Argentina
| | | | | | - Daniel W Sirkis
- Department of Neurology, University of California, San Francisco, San Francisco, California, USA
- Weil Institute of Neuroscience, University of California, San Francisco, San Francisco, California, USA
| | - Salvatore Spina
- Department of Neurology, University of California, San Francisco, San Francisco, California, USA
| | - Jennifer S Yokoyama
- Department of Neurology, University of California, San Francisco, San Francisco, California, USA
- Weil Institute of Neuroscience, University of California, San Francisco, San Francisco, California, USA
| | | | - Kenneth S Kosik
- University of California Santa Barbara, Santa Barbara, California, USA
| | - Diana Matallana
- Pontificia Universidad Javeriana, Bogota, Colombia
- Hospital Universitario Fundación Santa Fe, Bogotá, Colombia
| | - Agustín Ibáñez
- Latin American Institute for Brain Health (BrainLat), Universidad Adolfo Ibanez, Adolfo Ibanez University, Santiago, Chile, Santiago de Chile, Chile
- Global Brain Health Institute (GBHI), Trinity College Dublin, Dublin, Ireland
- Cognitive Neuroscience Center (CNC), Universidad de San Andres & CONICET, Buenos Aires, Argentina
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Vieira SRL, Morris HR. Neurodegenerative Disease Risk in Carriers of Autosomal Recessive Disease. Front Neurol 2021; 12:679927. [PMID: 34149605 PMCID: PMC8211888 DOI: 10.3389/fneur.2021.679927] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 05/14/2021] [Indexed: 01/19/2023] Open
Abstract
Genetics has driven significant discoveries in the field of neurodegenerative diseases (NDDs). An emerging theme in neurodegeneration warrants an urgent and comprehensive update: that carrier status of early-onset autosomal recessive (AR) disease, typically considered benign, is associated with an increased risk of a spectrum of late-onset NDDs. Glucosylceramidase beta (GBA1) gene mutations, responsible for the AR lysosomal storage disorder Gaucher disease, are a prominent example of this principle, having been identified as an important genetic risk factor for Parkinson disease. Genetic analyses have revealed further examples, notably GRN, TREM2, EIF2AK3, and several other LSD and mitochondria function genes. In this Review, we discuss the evidence supporting the strikingly distinct allele-dependent clinical phenotypes observed in carriers of such gene mutations and its impact on the wider field of neurodegeneration.
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Affiliation(s)
| | - Huw R. Morris
- Department of Clinical and Movement Neurosciences, University College London, Queen Square Institute of Neurology, London, United Kingdom
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Samanci B, Bilgiç B, Gelişin Ö, Tepgeç F, Guven G, Tüfekçioğlu Z, Alaylıoğlu M, Hanagasi HA, Gürvit H, Guerreiro R, Hardy J, Emre M. TREM2 variants as a possible cause of frontotemporal dementia with distinct neuroimaging features. Eur J Neurol 2021; 28:2603-2613. [PMID: 33969597 DOI: 10.1111/ene.14908] [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: 03/16/2021] [Revised: 04/30/2021] [Accepted: 05/03/2021] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND PURPOSE Nasu-Hakola disease (NHD) is a rare, autosomal recessive disorder characterized by skeletal and neurological symptoms. Behavioral symptoms with cognitive impairment may mimic the behavioral variant of frontotemporal dementia (bvFTD) and other early-onset dementias. Our patients were analyzed and the literature was reviewed to delineate neurological and neuroimaging findings suggestive of NHD. METHOD Fourteen patients carrying a pathogenic mutation in the TREM2 gene were found in our database. Demographic, clinical, laboratory and radiological data were retrieved and analyzed. RESULTS The presenting clinical picture was behavioral changes with cognitive decline resembling bvFTD in all patients. The mean age was 37.1 ± 4.97 years and the mean duration of the disease was 8.9 ± 3.51 years. Only two patients had typical bone cysts. Seven patients had bilateral calcification of the basal ganglia in computed tomography of the brain. Magnetic resonance imaging of the brain revealed severe atrophy of the corpus callosum, enlargement of the ventricles, atrophy of the caudate nuclei and periventricular white matter changes in all patients. Symmetrical global atrophy of the brain mainly affecting frontoparietal and lateral temporal regions were observed in all cases, and 13 patients had atrophy of the hippocampus. Cerebrospinal fluid examination of 10 patients showed elevated protein levels in six and the presence of oligoclonal bands in four patients. CONCLUSION A combination of white matter changes, enlarged ventricles, atrophy of the caudate nuclei and thinning of the corpus callosum in magnetic resonance imaging strongly suggests NHD in patients with FTD syndrome. Molecular genetic analysis should be performed in suspected cases, and families should receive genetic counseling.
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Affiliation(s)
- Bedia Samanci
- Behavioral Neurology and Movement Disorders Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Başar Bilgiç
- Behavioral Neurology and Movement Disorders Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Özlem Gelişin
- Behavioral Neurology and Movement Disorders Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Fatih Tepgeç
- Department of Medical Genetics, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Gamze Guven
- Department of Genetics, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
| | - Zeynep Tüfekçioğlu
- Behavioral Neurology and Movement Disorders Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Merve Alaylıoğlu
- Department of Medical Biology, Cerrahpasa Faculty of Medicine, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Hasmet A Hanagasi
- Behavioral Neurology and Movement Disorders Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Hakan Gürvit
- Behavioral Neurology and Movement Disorders Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Rita Guerreiro
- Center for Neurodegenerative Science, Van Andel Institute, Grand Rapids, MI, USA
| | - John Hardy
- Department of Neurodegenerative Disorders, Institute of Neurology, University College London, London, UK
| | - Murat Emre
- Behavioral Neurology and Movement Disorders Unit, Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
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Knight AC, Brill SA, Solis CV, Richardson MR, McCarron ME, Queen SE, Bailey CC, Mankowski JL. Differential regulation of TREM2 and CSF1R in CNS macrophages in an SIV/macaque model of HIV CNS disease. J Neurovirol 2020; 26:511-519. [PMID: 32488843 DOI: 10.1007/s13365-020-00844-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 02/11/2020] [Accepted: 04/13/2020] [Indexed: 11/26/2022]
Abstract
HIV-associated neuroinflammation is primarily driven by CNS macrophages including microglia. Regulation of these immune responses, however, remains to be characterized in detail. Using the SIV/macaque model of HIV, we evaluated CNS expression of triggering receptor expressed on myeloid cells 2 (TREM2) which is constitutively expressed by microglia and contributes to cell survival, proliferation, and differentiation. Loss-of-function mutations in TREM2 are recognized risk factors for neurodegenerative diseases including Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and Nasu-Hakola disease (NHD); recent reports have also indicated a role for TREM2 in HIV-associated neuroinflammation. Using in situ hybridization (ISH) and qRT-PCR, TREM2 mRNA levels were found to be significantly elevated in frontal cortex of macaques with SIV encephalitis compared with uninfected controls (P = 0.02). TREM2 protein levels were also elevated as measured by ELISA of frontal cortex tissue homogenates in these animals. Previously, we characterized the expression of CSF1R (colony-stimulating factor 1 receptor) in this model; the TREM2 and CSF1R promoters both contain a PU.1 binding site. While TREM2 and CSF1R mRNA levels in the frontal cortex were highly correlated (Spearman R = 0.79, P < 0.001), protein levels were not well correlated. In SIV-infected macaques released from ART to study viral rebound, neither TREM2 nor CSF1R mRNA increased with rebound viremia. However, CSF1R protein levels remained significantly elevated unlike TREM2 (P = 0.02). This differential expression suggests that TREM2 and CSF1R play unique, distinct roles in the pathogenesis of HIV CNS disease.
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MESH Headings
- Animals
- Antiretroviral Therapy, Highly Active/methods
- Antiviral Agents/pharmacology
- Drug Administration Schedule
- Encephalitis, Viral/drug therapy
- Encephalitis, Viral/genetics
- Encephalitis, Viral/immunology
- Encephalitis, Viral/virology
- Frontal Lobe/drug effects
- Frontal Lobe/immunology
- Frontal Lobe/virology
- Gene Expression Regulation
- Host-Pathogen Interactions/genetics
- Host-Pathogen Interactions/immunology
- Macaca nemestrina/genetics
- Macaca nemestrina/immunology
- Macaca nemestrina/virology
- Macrophages/drug effects
- Macrophages/immunology
- Macrophages/virology
- Male
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/immunology
- Microglia/drug effects
- Microglia/immunology
- Microglia/virology
- Promoter Regions, Genetic
- Protein Binding
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/immunology
- RNA, Messenger/genetics
- RNA, Messenger/immunology
- Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/genetics
- Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/immunology
- Simian Acquired Immunodeficiency Syndrome/drug therapy
- Simian Acquired Immunodeficiency Syndrome/genetics
- Simian Acquired Immunodeficiency Syndrome/immunology
- Simian Acquired Immunodeficiency Syndrome/virology
- Simian Immunodeficiency Virus/drug effects
- Simian Immunodeficiency Virus/growth & development
- Simian Immunodeficiency Virus/immunology
- Trans-Activators/genetics
- Trans-Activators/immunology
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Affiliation(s)
- Audrey C Knight
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Samuel A Brill
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Clarisse V Solis
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Morgan R Richardson
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Megan E McCarron
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Suzanne E Queen
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
| | - Charles C Bailey
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA
- Emmune, Inc., 130 Scripps Way, Jupiter, Florida, USA
| | - Joseph L Mankowski
- Department of Molecular and Comparative Pathobiology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
- Department of Neurology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
- Department of Pathology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
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6
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Dardiotis E, Rikos D, Siokas V, Aloizou AM, Tsouris Z, Sakalakis E, Brotis AG, Bogdanos DP, Hadjigeorgiou GM. Assessment of TREM2 rs75932628 variant's association with Parkinson's disease in a Greek population and Meta-analysis of current data. Int J Neurosci 2020; 131:544-548. [PMID: 32250197 DOI: 10.1080/00207454.2020.1750388] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
BACKGROUND Α number of genetic variants are considered to confer susceptibility to Parkinson's disease (PD). Rs75392628 (R47H), a rare variant of TREM2 gene, has been linked to PD, although its role on PD remains conflicting. OBJECTIVE Detection of a possible contribution of rs75392628 variant of TREM2 gene to PD risk. METHODS A total of 358 PD patients and 358 healthy controls genotyped for rs75392628. In addition, a meta-analysis was performed by merging our results with those from previous studies. RESULTS The rare variant of rs75932628 (47H) of TREM2 gene was not detected on cohort. Meta-analysis of a total of 9271 PD cases and 9777 controls across 14 independent PD data sets from 9 studies, including the present study, did not show any statistically significant effect of rs75392628 on PD risk (ORFE:1.54 95% CI:0.87-2.73. ORRE: 1.54, 95%CI: 0.71-3.32). CONCLUSIONS Rs75392628 TREM2 variant is rather unlikely to be a major genetic risk contributor of PD.
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Affiliation(s)
- Efthimios Dardiotis
- Department of Neurology, Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa, Larissa, Greece
| | - Dimitrios Rikos
- Department of Neurology, Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa, Larissa, Greece
| | - Vasileios Siokas
- Department of Neurology, Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa, Larissa, Greece
| | - Athina-Maria Aloizou
- Department of Neurology, Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa, Larissa, Greece
| | - Zisis Tsouris
- Department of Neurology, Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa, Larissa, Greece
| | - Evagelos Sakalakis
- Department of Neurology, Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa, Larissa, Greece
| | - Alexandros G Brotis
- Department of Neurosurgery, University of Thessaly, University Hospital of Larissa, Larissa, Greece
| | - Dimitrios P Bogdanos
- Department of Rheumatology and Clinical Immunology, University General Hospital of Larissa, Faculty of Medicine, School of Health Sciences, University of Thessaly, Larissa, Greece.,Cellular Immunotherapy & Molecular Immunodiagnostics, Biomedical Section, Centre for Research and Technology-Hellas (CERTH), Institute for Research and Technology-Thessaly (IRETETH), Larissa, Greece
| | - Georgios M Hadjigeorgiou
- Department of Neurology, Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa, Larissa, Greece.,Department of Neurology, Medical School, University of Cyprus, Nicosia, Cyprus
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7
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Dash R, Choi HJ, Moon IS. Mechanistic insights into the deleterious roles of Nasu-Hakola disease associated TREM2 variants. Sci Rep 2020; 10:3663. [PMID: 32107424 PMCID: PMC7046722 DOI: 10.1038/s41598-020-60561-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 02/13/2020] [Indexed: 02/06/2023] Open
Abstract
Recently, the critical roles played by genetic variants of TREM2 (Triggering Receptor Expressed on Myeloid cells 2) in Alzheimer's disease have been aggressively highlighted. However, few studies have focused on the deleterious roles of Nasu-Hakola disease (NHD) associated TREM2 variants. In order to get insights into the contributions made by these variants to neurodegeneration, we investigated the influences of four NHD associated TREM2 mutations (Y38C, W50C, T66M, and V126G) on loss-of-function, and followed this with in silico prediction and conventional molecular dynamics simulation. NHD mutations were predicted to be highly deleterious by eight different in silico bioinformatics tools and found to induce conformational changes by molecular dynamics simulation. As compared with the wild-type, the four variants produced substantial differences in the collective motions of loop regions, which not only promoted structural remodeling in the CDR2 (complementarity-determining region 2) loop but also in the CDR1 loop, by changing inter- and intra-loop hydrogen bonding networks. In addition, structural studies in a free energy landscape analysis showed that Y38, T66, and V126 are crucial for maintaining the structural features of CDR1 and CDR2 loops, and that mutations in these positions produced steric clashes and loss of ligand binding. These results showed the presence of mutations in the TREM2 ectodomain induced flexibility and caused structural alterations. Dynamical scenarios, as provided by the present study, may be critical to our understanding of the roles of these TREM2 mutations in neurodegenerative diseases.
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Affiliation(s)
- Raju Dash
- Department of Anatomy, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Ho Jin Choi
- Department of Anatomy, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea
| | - Il Soo Moon
- Department of Anatomy, Dongguk University College of Medicine, Gyeongju, 38066, Republic of Korea.
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8
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Dean HB, Roberson ED, Song Y. Neurodegenerative Disease-Associated Variants in TREM2 Destabilize the Apical Ligand-Binding Region of the Immunoglobulin Domain. Front Neurol 2019; 10:1252. [PMID: 32021611 PMCID: PMC6985895 DOI: 10.3389/fneur.2019.01252] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 11/11/2019] [Indexed: 01/22/2023] Open
Abstract
Single nucleotide variations in Triggering Receptor Expressed on Myeloid Cells 2 (TREM2) have been linked to both late-onset Alzheimer's disease and behavioral variant frontotemporal dementia (FTD), the latter presenting either in isolation or with cystic bone lesions in a condition called Nasu-Hakola disease. Models of the extracellular domain of TREM2 show that Nasu-Hakola disease-associated mutations are grossly inactivating by truncation, frameshift, or unfolding, that Alzheimer's disease (AD)-associated variants localize to a putative ligand-interacting region (PLIR) on the extracellular surface, and that FTD-associated variants are found in the hydrophobic core. However, while these disease-associated residues are predicted to play some role in disrupting ligand binding to the extracellular domain of TREM2, how they ultimately lead to disease remains unknown. Here, we used in silico molecular modeling to investigate all-atom models of TREM2 and characterize the effects on conformation and dynamical motion of AD-associated R47H and R62H as well as FTD-associated T96K, D86V, and T66M variants compared to the benign N68K variant and the common variant. Our model, which is based on a published 2.2 Å resolution crystal structure of the TREM2 extracellular domain, finds that both AD- and FTD-associated variants cause localized instability in three loops adjacent to the PLIR that correspond to the complementarity-determining regions (CDRs) of antibodies. This instability ultimately disrupts tethering between these CDRs and the core of the immunoglobulin domain, exposing a group of otherwise-buried, negatively charged residues. This instability and exposure of negatively charged residues is most severe following introduction of the T66M variant that has been described as causing FTD even in the heterozygous state and is less severe following introduction of variants that are less strongly tied to FTD or of those associated with AD. Thus, our results provide further evidence that the proposed loss-of-function caused by neurodegenerative disease-associated variants may be driven by altered conformational stability of the ligand-interacting CDR and, ultimately, loss of affinity or specificity for TREM2 ligands.
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Affiliation(s)
- Hunter B Dean
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL, United States.,Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, United States.,Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, United States.,Alzheimer's Disease Center, University of Alabama at Birmingham, Birmingham, AL, United States.,Medical Scientist Training Program, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Erik D Roberson
- Department of Neurology, University of Alabama at Birmingham, Birmingham, AL, United States.,Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, United States.,Alzheimer's Disease Center, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Yuhua Song
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL, United States
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9
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Redaelli V, Salsano E, Colleoni L, Corbetta P, Tringali G, Del Sole A, Giaccone G, Rossi G. Frontotemporal Dementia and Chorea Associated with a Compound Heterozygous TREM2 Mutation. J Alzheimers Dis 2019; 63:195-201. [PMID: 29578490 DOI: 10.3233/jad-180018] [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] [Indexed: 12/24/2022]
Abstract
Frontotemporal dementia (FTD) is clinically characterized by behavioral changes, language impairment, and executive dysfunction. FTD usually belongs to the frontotemporal lobar degeneration (FTLD) disease group, and its familial forms are dominantly inherited and linked to a group of genes relevant to frontal and temporal brain pathology, such as MAPT, GRN, C9ORF72, TARDBP, CHMP2B, VCP, and FUS. However, FTD can also be associated with different clinical or pathological phenotypes caused by mutations in other genes, whose heredity can be dominant or recessive. In this work we report on a familial case of FTD characterized by behavioral changes and aphasia, very early onset and very long duration, choreic movements, and white matter lesions at magnetic resonance imaging. We performed a wide-range genetic analysis, using a next generation sequencing approach, to evaluate a number of genes involved in neurodegeneration. We found a previously unreported compound heterozygous mutation in TREM2, that is commonly associated with the recessively inherited Nasu-Hakola disease. We discuss the differential diagnosis to be taken into account in cases of FTD presenting with atypical features.
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Affiliation(s)
- Veronica Redaelli
- Unit of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Ettore Salsano
- Unit of Neurodegenerative and Neurometabolic Rare Diseases, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Lara Colleoni
- Unit of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Paola Corbetta
- Unit of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Giovanni Tringali
- Unit of Neurosurgery III, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Angelo Del Sole
- Department of Diagnostic Services, Unit of Nuclear Medicine, ASST Santi Paolo e Carlo, Milan, Italy
| | - Giorgio Giaccone
- Unit of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Giacomina Rossi
- Unit of Neurology V and Neuropathology, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
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10
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Rikos D, Siokas V, Aloizou AM, Tsouris Z, Aslanidou P, Koutsis G, Anagnostouli M, Bogdanos DP, Grigoriadis N, Hadjigeorgiou GM, Dardiotis E. TREM2 R47H (rs75932628) variant is unlikely to contribute to Multiple Sclerosis susceptibility and severity in a large Greek MS cohort. Mult Scler Relat Disord 2019; 35:116-118. [PMID: 31362167 DOI: 10.1016/j.msard.2019.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 06/28/2019] [Accepted: 07/19/2019] [Indexed: 01/10/2023]
Abstract
BACKGROUND Multiple Sclerosis is a multifactorial autoimmune disease of the central nervous system, characterized by focal inflammation, demyelination and secondary axonal injury. TREM2 is a signaling protein which participates in the innate immune system by implication to inflammation, proliferation and phagocytosis. The R47H (rs75392628) rare variant of the TREM2 gene has been related to various neurological diseases and leads to impaired signaling, lipoprotein binding, lipoprotein uptake and surface uptake. AIM To assess the role of TREM2 rs75932628 on MS risk through a genetic candidate gene association case-control study in a Greek population. METHODS 1246 MS cases and 398 controls were genotyped for this variant. RESULTS No MS or healthy subjects carried the variant. CONCLUSION This variant does not seem to play a determining role in the pathogenesis of MS, although further studies examining the presence of TREM2 mutations in other, phylogenetically different populations and the epigenetic regulation of this gene are needed in order to thoroughly investigate its role in MS.
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Affiliation(s)
- Dimitrios Rikos
- Department of Neurology, Laboratory of Neurogenetics, University Hospital of Larissa, University of Thessaly, Larissa, Greece
| | - Vasileios Siokas
- Department of Neurology, Laboratory of Neurogenetics, University Hospital of Larissa, University of Thessaly, Larissa, Greece
| | - Athina-Maria Aloizou
- Department of Neurology, Laboratory of Neurogenetics, University Hospital of Larissa, University of Thessaly, Larissa, Greece
| | - Zisis Tsouris
- Department of Neurology, Laboratory of Neurogenetics, University Hospital of Larissa, University of Thessaly, Larissa, Greece
| | - Paraskevi Aslanidou
- Department of Neurology, Laboratory of Neurogenetics, University Hospital of Larissa, University of Thessaly, Larissa, Greece
| | - Georgios Koutsis
- Neurogenetics Unit, 1st Department of Neurology, University of Athens, Medical School, Eginition Hospital, Athens, Greece
| | - Maria Anagnostouli
- Demyelinating Diseases Unit and Immunogenetics Laboratory, 1st Department of Neurology, School of Medicine, Eginition Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Dimitrios P Bogdanos
- Cellular Immunotherapy & Molecular Immunodiagnostics, Biomedical Section, Centre for Research and Technology-Hellas (CERTH), Institute for Research and Technology-Thessaly (IRETETH), Larissa, Greece
| | - Nikolaos Grigoriadis
- Laboratory of Experimental Neurology and Neuroimmunology, B' Department of Neurology, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Georgios M Hadjigeorgiou
- Department of Neurology, Laboratory of Neurogenetics, University Hospital of Larissa, University of Thessaly, Larissa, Greece; Department of Neurology, Medical School, University of Cyprus, Nicosia, Cyprus
| | - Efthimios Dardiotis
- Department of Neurology, Laboratory of Neurogenetics, University Hospital of Larissa, University of Thessaly, Larissa, Greece.
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11
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Wang S, Colonna M. Microglia in Alzheimer's disease: A target for immunotherapy. J Leukoc Biol 2019; 106:219-227. [PMID: 30725482 DOI: 10.1002/jlb.mr0818-319r] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 01/11/2018] [Accepted: 01/14/2019] [Indexed: 12/29/2022] Open
Abstract
Microglia are resident Mϕs of the CNS that play pleiotropic functions in brain development and homeostasis. Impaired microglial functions are thought to be involved in the onset and progression of various neurodevelopmental and neurodegenerative diseases. Thus, understanding microglia in these settings may indicate new approaches for therapeutic intervention. Here, we review recent evidence implicating microglia in Alzheimer's disease and discuss potential therapeutic strategies targeting microglia and their receptors in this disease.
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Affiliation(s)
- Shoutang Wang
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri, USA
| | - Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri, USA
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12
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Suárez-Calvet M, Morenas-Rodríguez E, Kleinberger G, Schlepckow K, Araque Caballero MÁ, Franzmeier N, Capell A, Fellerer K, Nuscher B, Eren E, Levin J, Deming Y, Piccio L, Karch CM, Cruchaga C, Shaw LM, Trojanowski JQ, Weiner M, Ewers M, Haass C. Early increase of CSF sTREM2 in Alzheimer's disease is associated with tau related-neurodegeneration but not with amyloid-β pathology. Mol Neurodegener 2019; 14:1. [PMID: 30630532 PMCID: PMC6327425 DOI: 10.1186/s13024-018-0301-5] [Citation(s) in RCA: 153] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 12/04/2018] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND TREM2 is a transmembrane receptor that is predominantly expressed by microglia in the central nervous system. Rare variants in the TREM2 gene increase the risk for late-onset Alzheimer's disease (AD). Soluble TREM2 (sTREM2) resulting from shedding of the TREM2 ectodomain can be detected in the cerebrospinal fluid (CSF) and is a surrogate measure of TREM2-mediated microglia function. CSF sTREM2 has been previously reported to increase at different clinical stages of AD, however, alterations in relation to Amyloid β-peptide (Aβ) deposition or additional pathological processes in the amyloid cascade (such as tau pathology or neurodegeneration) remain unclear. In the current cross-sectional study, we employed the biomarker-based classification framework recently proposed by the NIA-AA consensus guidelines, in combination with clinical staging, in order to examine the CSF sTREM2 alterations at early asymptomatic and symptomatic stages of AD. METHODS A cross-sectional study of 1027 participants of the Alzheimer's Disease Imaging Initiative (ADNI) cohort, including 43 subjects carrying TREM2 rare genetic variants, was conducted to measure CSF sTREM2 using a previously validated enzyme-linked immunosorbent assay (ELISA). ADNI participants were classified following the A/T/N framework, which we implemented based on the CSF levels of Aβ1-42 (A), phosphorylated tau (T) and total tau as a marker of neurodegeneration (N), at different clinical stages defined by the clinical dementia rating (CDR) score. RESULTS CSF sTREM2 differed between TREM2 variants, whereas the p.R47H variant had higher CSF sTREM2, p.L211P had lower CSF sTREM2 than non-carriers. We found that CSF sTREM2 increased in early symptomatic stages of late-onset AD but, unexpectedly, we observed decreased CSF sTREM2 levels at the earliest asymptomatic phase when only abnormal Aβ pathology (A+) but no tau pathology or neurodegeneration (TN-), is present. CONCLUSIONS Aβ pathology (A) and tau pathology/neurodegeneration (TN) have differing associations with CSF sTREM2. While tau-related neurodegeneration is associated with an increase in CSF sTREM2, Aβ pathology in the absence of downstream tau-related neurodegeneration is associated with a decrease in CSF sTREM2.
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Affiliation(s)
- Marc Suárez-Calvet
- Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany. .,German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany. .,Barcelonaβeta Brain Research Center (BBRC), Pasqual Maragall Foundation, Barcelona, Catalonia, Spain.
| | - Estrella Morenas-Rodríguez
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany.,Department of Neurology, Institut d'Investigacions Biomèdiques, Hospital de la Santa Creu i Sant Pau, Universitat Autònoma de Barcelona, Barcelona, Catalonia, Spain
| | - Gernot Kleinberger
- Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany.,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Kai Schlepckow
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany
| | - Miguel Ángel Araque Caballero
- Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Nicolai Franzmeier
- Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Anja Capell
- Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Katrin Fellerer
- Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Brigitte Nuscher
- Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Erden Eren
- Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany.,Izmir International Biomedicine and Genome Institute Dokuz Eylul University, Izmir, Turkey.,Department of Neuroscience, Institute of Health Sciences, Dokuz Eylul University, Izmir, Turkey
| | - Johannes Levin
- German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany.,Department of Neurology, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Yuetiva Deming
- Department of Psychiatry, Washington University School of Medicine, Saint Louis, MO, USA
| | - Laura Piccio
- Department of Neurology, Washington University School of Medicine, St. Louis, MO, USA.,Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO, USA
| | - Celeste M Karch
- Department of Psychiatry, Washington University School of Medicine, Saint Louis, MO, USA.,Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO, USA.,Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Carlos Cruchaga
- Department of Psychiatry, Washington University School of Medicine, Saint Louis, MO, USA.,Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO, USA.,Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA
| | - Leslie M Shaw
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neurodegenerative Disease Research, Institute on Aging, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - John Q Trojanowski
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,Center for Neurodegenerative Disease Research, Institute on Aging, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Michael Weiner
- University of California at San Francisco, San Francisco, CA, USA
| | - Michael Ewers
- Institute for Stroke and Dementia Research, Klinikum der Universität München, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Christian Haass
- Chair of Metabolic Biochemistry, Biomedical Center (BMC), Faculty of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany. .,German Center for Neurodegenerative Diseases (DZNE) Munich, Munich, Germany. .,Munich Cluster for Systems Neurology (SyNergy), Munich, Germany.
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13
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The Role of APOE and TREM2 in Alzheimer's Disease-Current Understanding and Perspectives. Int J Mol Sci 2018; 20:ijms20010081. [PMID: 30587772 PMCID: PMC6337314 DOI: 10.3390/ijms20010081] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 12/19/2018] [Accepted: 12/21/2018] [Indexed: 12/12/2022] Open
Abstract
Alzheimer's disease (AD) is the leading cause of dementia worldwide. The extracellular deposits of Amyloid beta (Aβ) in the brain-called amyloid plaques, and neurofibrillary tangles-intracellular tau aggregates, are morphological hallmarks of the disease. The risk for AD is a complicated interplay between aging, genetic risk factors, and environmental influences. One of the Apolipoprotein E (APOE) alleles-APOEε4, is the major genetic risk factor for late-onset AD (LOAD). APOE is the primary cholesterol carrier in the brain, and plays an essential role in lipid trafficking, cholesterol homeostasis, and synaptic stability. Recent genome-wide association studies (GWAS) have identified other candidate LOAD risk loci, as well. One of those is the triggering receptor expressed on myeloid cells 2 (TREM2), which, in the brain, is expressed primarily by microglia. While the function of TREM2 is not fully understood, it promotes microglia survival, proliferation, and phagocytosis, making it important for cell viability and normal immune functions in the brain. Emerging evidence from protein binding assays suggests that APOE binds to TREM2 and APOE-containing lipoproteins in the brain as well as periphery, and are putative ligands for TREM2, thus raising the possibility of an APOE-TREM2 interaction modulating different aspects of AD pathology, potentially in an isoform-specific manner. This review is focusing on the interplay between APOE isoforms and TREM2 in association with AD pathology.
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14
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The role of TREM2 in Alzheimer's disease and other neurodegenerative disorders. Lancet Neurol 2018; 17:721-730. [PMID: 30033062 DOI: 10.1016/s1474-4422(18)30232-1] [Citation(s) in RCA: 146] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 06/04/2018] [Accepted: 06/06/2018] [Indexed: 12/12/2022]
Abstract
Alzheimer's disease is a genetically complex disorder; rare variants in the triggering receptor expressed on myeloid cells 2 (TREM2) gene have been shown to as much as triple an individual's risk of developing Alzheimer's disease. TREM2 is a transmembrane receptor expressed in cells of the myeloid lineage, and its association with Alzheimer's disease supports the involvement of immune and inflammatory pathways in the cause of the disease, rather than as a consequence of the disease. TREM2 variants associated with Alzheimer's disease induce partial loss of function of the TREM2 protein and alter the behaviour of microglial cells, including their response to amyloid plaques. TREM2 variants have also been shown to cause polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy and frontotemporal dementia. Although the low frequency of TREM2 variants makes it difficult to establish robust genotype-phenotype correlations, such studies are essential to enable a comprehensive understanding of the role of TREM2 in different neurological diseases, with the ultimate goal of developing novel therapeutic approaches.
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15
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Zhou Y, Ulland TK, Colonna M. TREM2-Dependent Effects on Microglia in Alzheimer's Disease. Front Aging Neurosci 2018; 10:202. [PMID: 30038567 PMCID: PMC6046445 DOI: 10.3389/fnagi.2018.00202] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 06/13/2018] [Indexed: 12/31/2022] Open
Abstract
Alzheimer's disease (AD) is a late-onset dementia characterized by the deposition of amyloid plaques and formation of neurofibrillary tangles (NFTs) which lead to neuronal loss and cognitive deficits. Abnormal protein aggregates in the AD brain are also associated with reactive microglia and astrocytes. Whether this glial response is beneficial or detrimental in AD pathology is under debate. Microglia are the resident innate immune cells in the central nervous system (CNS) that survey the surrounding environment. Genome-wide association studies (GWAS) have identified the R47H variant of triggering receptor expressed on myeloid cell 2 (TREM2) as a risk factor for late-onset AD (LOAD) with an odds ratio of 4.5. TREM2 is an immunoreceptor primarily present on microglia in the CNS that binds to polyanionic molecules. The transmembrane domain of TREM2 signals through DAP12, an adaptor protein that contains an immunoreceptor tyrosine-based activation motif (ITAM), which mediates TREM2 signaling and promotes microglial activation and survival. In mouse models of AD, Trem2 haplodeficiency and deficiency lead to reduced microglial clustering around amyloid β (Aβ) plaques, suggesting TREM2 is required for plaque-associated microglial responses. Recently, TREM2 has been shown to enhance microglial metabolism through the mammalian target of rapamycin (mTOR) pathway. Although aberrant metabolism has long been associated with AD, not much was known regarding how metabolism in microglia might affect disease progression. In this review, we discuss the role of TREM2 and metabolism in AD pathology, highlighting how TREM2-mediated microglial metabolism modulates AD pathogenesis.
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Affiliation(s)
| | | | - Marco Colonna
- Department of Pathology and Immunology, Washington University in St. Louis, St. Louis, MO, United States
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16
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Abstract
Microglia are a subset of tissue macrophages that constitute the major immune cell type of the central nervous system. These cells have long been known to change their morphology and functions in response to various neurological insults. Recently, a plethora of unbiased transcriptomics studies have revealed that across a broad spectrum of neurodegeneration-like disease models, microglia adopt a similar activation signature and perform similar functions. Despite these commonalities in response, the role of microglia has been described as both positive and negative in different murine disease models. In humans, genetic association studies have revealed strong connections between microglia genes and various neurodegenerative diseases, and mechanistic investigations of these mutations have added another layer of complexity. Here, we provide an overview of studies that have built a case for a common microglial response to neurodegeneration and discuss pathways that may be important to initiate and sustain this response; delineate the multifaceted functions of activated microglia spanning different diseases; and discuss insights from studying genes associated with disease in humans. We argue that strong evidence causally links activated microglia function to neurodegeneration and discuss what seems to be a conflict between mouse models and human genetics.
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Affiliation(s)
- Wilbur M Song
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, United States
| | - Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, United States.
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17
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Kang SS, Kurti A, Baker KE, Liu CC, Colonna M, Ulrich JD, Holtzman DM, Bu G, Fryer JD. Behavioral and transcriptomic analysis of Trem2-null mice: not all knockout mice are created equal. Hum Mol Genet 2018; 27:211-223. [PMID: 29040522 PMCID: PMC5886290 DOI: 10.1093/hmg/ddx366] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 08/31/2017] [Accepted: 09/21/2017] [Indexed: 01/08/2023] Open
Abstract
It is clear that innate immune system status is altered in numerous neurodegenerative diseases. Human genetic studies have demonstrated that triggering receptor expressed in myeloid cells 2 (TREM2) coding variants have a strong association with Alzheimer's disease (AD) and other neurodegenerative diseases. To more thoroughly understand the impact of TREM2 in vivo, we studied the behavioral and cognitive functions of wild-type (WT) and Trem2-/- (KO) mice during basal conditions and brain function in the context of innate immune stimulation with peripherally administered lipopolysaccharide (LPS). Early markers of neuroinflammation preceded Aif1 and Trem2 upregulation that occurred at later stages (24-48 h post-LPS). We performed a transcriptomic study of these cohorts and found numerous transcripts and pathways that were altered in Trem2-/- mice both at baseline and 48 h after LPS challenge. Importantly, our transcriptome analysis revealed that our Trem2-/- mouse line (Velocigene allele) results in exaggerated Treml1 upregulation. In contrast, aberrantly high Treml1 expression was absent in the Trem2 knockout line generated by the Colonna lab and the Jackson Labs CRISPR/Cas9 Trem2 knockout line. Notably, removal of the floxed neomycin selection cassette ameliorated aberrant Treml1 expression, validating the artifactual nature of Treml1 expression in the original Trem2-/- Velocigene line. Clearly further studies are needed to decipher whether the Treml1 transcriptional artifact is functionally meaningful, but our data indicate that caution is warranted when interpreting functional studies with this particular line. Additionally, our results indicate that other Velocigene alleles or targeting strategies with strong heterologous promoters need to carefully consider downstream genes.
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Affiliation(s)
- Silvia S Kang
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Aishe Kurti
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Kelsey E Baker
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Chia-Chen Liu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Marco Colonna
- Department of Pathology and Immunology, Washington University, St. Louis, MO 63110, USA
| | - Jason D Ulrich
- Department of Neurology, Washington University, St. Louis, MO 63110, USA
| | - David M Holtzman
- Department of Neurology, Washington University, St. Louis, MO 63110, USA
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
- Neurobiology of Disease Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL 32224, USA
| | - John D Fryer
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
- Neurobiology of Disease Graduate Program, Mayo Clinic Graduate School of Biomedical Sciences, Jacksonville, FL 32224, USA
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18
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Su WH, Shi ZH, Liu SL, Wang XD, Liu S, Ji Y. The rs75932628 and rs2234253 polymorphisms of the TREM2 gene were associated with susceptibility to frontotemporal lobar degeneration in Caucasian populations. Ann Hum Genet 2018; 82:177-185. [PMID: 29322490 DOI: 10.1111/ahg.12241] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 09/30/2017] [Accepted: 11/29/2017] [Indexed: 12/29/2022]
Abstract
Polymorphisms of the triggering receptor expressed on myeloid cells 2 (TREM2) gene have been reported to be potentially associated with the risks of developing frontotemporal lobar degeneration (FTLD), with inconsistent conclusions. This study aims to comprehensively investigate the potential role of TREM2 variants in FTLD risks via a meta-analysis. We included a total of eight eligible articles. For TREM2 rs75932628, we observed a significantly increased FTLD risk in the models of T vs. C [Association Test, odds ratio (OR) = 2.43, 95% confidence interval (CI) = 1.43∼4.14, P = 0.001], CT vs. CC (OR = 2.27, 95% CI = 1.39∼3.71, P = 0.001), CT + TT vs. CC (OR = 2.27, 95% CI = 1.38∼3.71, P = 0.001), and Carrier T vs. C (OR = 2.26, 95% CI = 1.38∼3.69, P = 0.001). Similarly, we observed positive results for TREM2 rs2234253 in all of the genetic models (all OR > 1, P = 0.030). Nevertheless, we did not observe any statistical difference between the case and control groups in the pooled analyses of TREM2 rs142232675 and rs143332484 (all P > 0.05). Our findings identified the rs75932628 and rs2234253 polymorphisms of the TREM2 gene as risk factors for FTLD in Caucasian populations.
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Affiliation(s)
- Wen-Hua Su
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, China.,Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, China
| | - Zhi-Hong Shi
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, China.,Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, China
| | - Shu-Ling Liu
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, China.,Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, China
| | - Xiao-Dan Wang
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, China.,Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, China
| | - Shuai Liu
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, China.,Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, China
| | - Yong Ji
- Department of Neurology, Tianjin Huanhu Hospital, Tianjin, China.,Tianjin Key Laboratory of Cerebral Vascular and Neurodegenerative Diseases, Tianjin Huanhu Hospital, Tianjin, China
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19
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Jay TR, von Saucken VE, Landreth GE. TREM2 in Neurodegenerative Diseases. Mol Neurodegener 2017; 12:56. [PMID: 28768545 PMCID: PMC5541421 DOI: 10.1186/s13024-017-0197-5] [Citation(s) in RCA: 246] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 07/20/2017] [Indexed: 12/12/2022] Open
Abstract
TREM2 variants have been identified as risk factors for Alzheimer's disease (AD) and other neurodegenerative diseases (NDDs). Because TREM2 encodes a receptor exclusively expressed on immune cells, identification of these variants conclusively demonstrates that the immune response can play an active role in the pathogenesis of NDDs. These TREM2 variants also confer the highest risk for developing Alzheimer's disease of any risk factor identified in nearly two decades, suggesting that understanding more about TREM2 function could provide key insights into NDD pathology and provide avenues for novel immune-related NDD biomarkers and therapeutics. The expression, signaling and function of TREM2 in NDDs have been extensively investigated in an effort to understand the role of immune function in disease pathogenesis and progression. We provide a comprehensive review of our current understanding of TREM2 biology, including new insights into the regulation of TREM2 expression, and TREM2 signaling and function across NDDs. While many open questions remain, the current body of literature provides clarity on several issues. While it is still often cited that TREM2 expression is decreased by pro-inflammatory stimuli, it is now clear that this is true in vitro, but inflammatory stimuli in vivo almost universally increase TREM2 expression. Likewise, while TREM2 function is classically described as promoting an anti-inflammatory phenotype, more than half of published studies demonstrate a pro-inflammatory role for TREM2, suggesting that its role in inflammation is much more complex. Finally, these components of TREM2 biology are applied to a discussion of how TREM2 impacts NDD pathologies and the latest assessment of how these findings might be applied to immune-directed clinical biomarkers and therapeutics.
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Affiliation(s)
- Taylor R. Jay
- Department of Neurosciences, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106 USA
| | - Victoria E. von Saucken
- Department of Neurosciences, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106 USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, 320 W 15th Street, Indianapolis, IN 46202 USA
| | - Gary E. Landreth
- Department of Neurosciences, Case Western Reserve University, School of Medicine, 10900 Euclid Avenue, Cleveland, OH 44106 USA
- Stark Neurosciences Research Institute, Indiana University School of Medicine, 320 W 15th Street, Indianapolis, IN 46202 USA
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20
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Arcuri C, Mecca C, Bianchi R, Giambanco I, Donato R. The Pathophysiological Role of Microglia in Dynamic Surveillance, Phagocytosis and Structural Remodeling of the Developing CNS. Front Mol Neurosci 2017; 10:191. [PMID: 28674485 PMCID: PMC5474494 DOI: 10.3389/fnmol.2017.00191] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 05/30/2017] [Indexed: 12/13/2022] Open
Abstract
In vertebrates, during an early wave of hematopoiesis in the yolk sac between embryonic day E7.0 and E9.0, cells of mesodermal leaflet addressed to macrophage lineage enter in developing central nervous system (CNS) and originate the developing native microglial cells. Depending on the species, microglial cells represent 5–20% of glial cells resident in adult brain. Here, we briefly discuss some canonical functions of the microglia, i.e., cytokine secretion and functional transition from M1 to M2 phenotype. In addition, we review studies on the non-canonical functions of microglia such as regulation of phagocytosis, synaptic pruning, and sculpting postnatal neural circuits. In this latter context the contribution of microglia to some neurodevelopmental disorders is now well established. Nasu-Hakola (NHD) disease is considered a primary microgliopathy with alterations of the DNAX activation protein 12 (DAP12)-Triggering receptor expressed on myeloid cells 2 (TREM-2) signaling and removal of macromolecules and apoptotic cells followed by secondary microglia activation. In Rett syndrome Mecp2-/- microglia shows a substantial impairment of phagocytic ability, although the role of microglia is not yet clear. In a mouse model of Tourette syndrome (TS), microglia abnormalities have also been described, and deficient microglia-mediated neuroprotection is obvious. Here we review the role of microglial cells in neurodevelopmental disorders without inflammation and on the complex role of microglia in developing CNS.
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Affiliation(s)
- Cataldo Arcuri
- Department of Experimental Medicine, Centro Universitario per la Ricerca sulla Genomica Funzionale, Perugia Medical School, University of PerugiaPerugia, Italy
| | - Carmen Mecca
- Department of Experimental Medicine, Centro Universitario per la Ricerca sulla Genomica Funzionale, Perugia Medical School, University of PerugiaPerugia, Italy
| | - Roberta Bianchi
- Department of Experimental Medicine, Centro Universitario per la Ricerca sulla Genomica Funzionale, Perugia Medical School, University of PerugiaPerugia, Italy
| | - Ileana Giambanco
- Department of Experimental Medicine, Centro Universitario per la Ricerca sulla Genomica Funzionale, Perugia Medical School, University of PerugiaPerugia, Italy
| | - Rosario Donato
- Department of Experimental Medicine, Centro Universitario per la Ricerca sulla Genomica Funzionale, Perugia Medical School, University of PerugiaPerugia, Italy
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21
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Yeh FL, Hansen DV, Sheng M. TREM2, Microglia, and Neurodegenerative Diseases. Trends Mol Med 2017; 23:512-533. [DOI: 10.1016/j.molmed.2017.03.008] [Citation(s) in RCA: 180] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 02/15/2017] [Accepted: 03/26/2017] [Indexed: 01/17/2023]
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22
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Owens R, Grabert K, Davies CL, Alfieri A, Antel JP, Healy LM, McColl BW. Divergent Neuroinflammatory Regulation of Microglial TREM Expression and Involvement of NF-κB. Front Cell Neurosci 2017; 11:56. [PMID: 28303091 PMCID: PMC5332401 DOI: 10.3389/fncel.2017.00056] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 02/15/2017] [Indexed: 12/28/2022] Open
Abstract
The triggering receptor expressed on myeloid cells (TREM) family of proteins are cell surface receptors with important roles in regulation of myeloid cell inflammatory activity. In the central nervous system, TREM2 is implicated in further roles in microglial homeostasis, neuroinflammation and neurodegeneration. Different TREM receptors appear to have contrasting roles in controlling myeloid immune activity therefore the relative and co-ordinated regulation of their expression is important to understand but is currently poorly understood. We sought to determine how microglial TREM expression is affected under neuroinflammatory conditions in vitro and in vivo. Our data show that microglial Trem1 and Trem2 gene expression are regulated in an opposing manner by lipopolysaccharide (LPS) in vitro in both adult murine and human microglia. LPS caused a significant induction of Trem1 and a contrasting suppression of Trem2 expression. We also observed similar divergent Trem1 and Trem2 responses in vivo in response to acute brain inflammation and acute cerebral ischaemia. Our data show that inhibition of NF-κB activation prevents the LPS-induced alterations in both Trem1 and Trem2 expression in vitro indicating NF-κB as a common signaling intermediate controlling these divergent responses. Distinct patterns of microglial Trem1 induction and Trem2 suppression to different Toll-like receptor (TLR) ligands were also evident, notably with Trem1 induction restricted to those ligands activating TLRs signaling via TRIF. Our data show co-ordinated but divergent regulation of microglial TREM receptor expression with a central role for NF-κB. Neuroinflammatory conditions that alter the balance in TREM expression could therefore be an important influence on microglial inflammatory and homeostatic activity with implications for neuroinflammatory and neurodegenerative disease.
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Affiliation(s)
- Rosie Owens
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh Midlothian, UK
| | - Kathleen Grabert
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh Midlothian, UK
| | - Claire L Davies
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh Midlothian, UK
| | - Alessio Alfieri
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh Midlothian, UK
| | - Jack P Antel
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University Montreal, QC, Canada
| | - Luke M Healy
- Neuroimmunology Unit, Montreal Neurological Institute, McGill University Montreal, QC, Canada
| | - Barry W McColl
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh Midlothian, UK
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23
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A novel mutation in TREM2 gene causing Nasu-Hakola disease and review of the literature. Neurobiol Aging 2017; 53:194.e13-194.e22. [PMID: 28214109 DOI: 10.1016/j.neurobiolaging.2017.01.015] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2016] [Accepted: 01/11/2017] [Indexed: 11/20/2022]
Abstract
Nasu-hakola disease (NHD) is a rare disease characterized by bone cysts and fractures, frontal lobe syndrome, and progressive presenile dementia. NHD may be the prototype of primary microglial disorders of the CNS or, as they have been coined, "microgliopathies". Mutations in TREM2 and TYROBP genes are known to cause NHD. Interestingly, recent evidence-associated rare genetic variants of TREM2 gene with increased risk of Alzheimer's disease, frontotemporal dementia, amyotrophic lateral sclerosis, and Parkinson's disease. Here, we report a 33-year-old Greek female with phenotype suggestive of NHD. Full gene sequencing of the TREM2 and TYROBP genes revealed a novel mutation in exon 2 of TREM2 gene, namely c.244G>T (p.W50C) and heterozygosity in the parents and her brother. This report extends the range of TREM2 mutations that cause NHD phenotype. In addition, we provide a comprehensive review of all reported in the literature TREM2 gene mutations and the respective wide spectrum of clinical manifestations that highlights the importance of considering TREM2 gene mutations in a variety of neurodegenerative phenotypes.
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Woollacott IOC, Rohrer JD. The clinical spectrum of sporadic and familial forms of frontotemporal dementia. J Neurochem 2016; 138 Suppl 1:6-31. [PMID: 27144467 DOI: 10.1111/jnc.13654] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 04/10/2016] [Accepted: 04/27/2016] [Indexed: 12/11/2022]
Abstract
The term frontotemporal dementia (FTD) describes a clinically, genetically and pathologically diverse group of neurodegenerative disorders. Symptoms of FTD can present in individuals in their 20s through to their 90s, but the mean age at onset is in the sixth decade. The most common presentation is with a change in personality and impaired social conduct (behavioural variant FTD). Less frequently patients present with language problems (primary progressive aphasia). Both of these groups of patients can develop motor features consistent with either motor neuron disease (usually the amyotrophic lateral sclerosis variant) or parkinsonism (most commonly a progressive supranuclear palsy or corticobasal syndrome). In about a third of cases FTD is familial, with mutations in the progranulin, microtubule-associated protein tau and chromosome 9 open reading frame 72 genes being the major causes. Mutations in a number of other genes including TANK-binding kinase 1 are rare causes of familial FTD. This review aims to clarify the often confusing terminology of FTD, and outline the various clinical features and diagnostic criteria of sporadic and familial FTD syndromes. It will also discuss the current major challenges in FTD research and clinical practice, and potential areas for future research. This review clarifies the terminology of frontotemporal dementia (FTD) and summarizes the various clinical features and most recent diagnostic criteria of sporadic and familial FTD syndromes. It also discusses the current major challenges in FTD research and clinical practice, and highlights potential areas for future research.
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Affiliation(s)
- Ione O C Woollacott
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
| | - Jonathan D Rohrer
- Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
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25
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Abstract
Genetic characterization of individuals at risk of Alzheimer's disease (AD), i.e. people having amyloid deposits in the brain without symptoms, people suffering from subjective cognitive decline (SCD) or mild cognitive impairment (MCI), has spurred the interests of researchers. However, their pre-dementia genetic profile remains mostly unexplored. In this study, we reviewed the loci related to phenotypes of AD, MCI and SCD from literature and performed the first meta-analyses evaluating the role of apolipoprotein E (APOE) in the risk of conversion from a healthy status to MCI and SCD. For AD dementia risk, an increased number of loci have been identified; to date, 28 genes have been associated with Late Onset AD. In MCI syndrome, APOE is confirmed as a pheno-conversion factor leading from MCI to AD, and clusterin is a promising candidate. Additionally, our meta-analyses revealed APOE as genetic risk factor to convert from a healthy status to MCI [OR = 1.849 (1.587-2.153); P = 2.80 × 10-15] and to a lesser extent from healthy status to SCD [OR = 1.151 (1.015-1.304); P = 0.028]. Thus, we believe that genetic studies in longitudinal SCD and MCI series may provide new therapeutic targets and improve the existing knowledge of AD. This type of studies must be completed on healthy subjects to better understand the natural disease resistance to brain insults and neurodegeneration.
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26
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Colonna M, Wang Y. TREM2 variants: new keys to decipher Alzheimer disease pathogenesis. Nat Rev Neurosci 2016; 17:201-7. [PMID: 26911435 DOI: 10.1038/nrn.2016.7] [Citation(s) in RCA: 264] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Genome-wide association studies have identified rare variants of the gene that encodes triggering receptor expressed on myeloid cells 2 (TREM2) - an immune receptor that is found in brain microglia - as risk factors for non-familial Alzheimer disease (AD). Furthermore, animal studies have indicated that microglia have an important role in the brain response to amyloid-β (Aβ) plaques and that TREM2 variants may have an impact on such a function. We discuss how TREM2 may control the microglial response to Aβ and its impact on microglial senescence, as well as the interaction of TREM2 with other molecules that are encoded by gene variants associated with AD and the hypothetical consequences of the cleavage of TREM2 from the cell surface.
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Affiliation(s)
- Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, Missouri 63108, USA
| | - Yaming Wang
- Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, USA
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27
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Zhu C, Herrmann US, Li B, Abakumova I, Moos R, Schwarz P, Rushing EJ, Colonna M, Aguzzi A. Triggering receptor expressed on myeloid cells-2 is involved in prion-induced microglial activation but does not contribute to prion pathogenesis in mouse brains. Neurobiol Aging 2015; 36:1994-2003. [PMID: 25816748 DOI: 10.1016/j.neurobiolaging.2015.02.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 02/04/2015] [Accepted: 02/21/2015] [Indexed: 10/23/2022]
Abstract
Dysfunctional variants of the innate immune cell surface receptor TREM2 (triggering receptor expressed on myeloid cells-2) were identified as major genetic risk factors for Alzheimer's disease and other neurodegenerative conditions. Here we assessed a possible involvement of TREM2 in prion disease. We report that TREM2 expression by microglia is significantly up-regulated upon prion infection. However, depletion of TREM2 did not affect disease incubation time and survival after intracerebral prion infection. Interestingly, markers of microglial activation were attenuated in prion-infected TREM2(-/-) mice, suggesting an involvement of TREM2 in prion-induced microglial activation. Further phenotype profiling of microglia revealed that TREM2 deficiency did not change microglial phenotypes. We conclude that TREM2 is involved in prion-induced microglial activation but does not noticeably modulate the pathogenesis of experimental prion infections.
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Affiliation(s)
- Caihong Zhu
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland.
| | - Uli S Herrmann
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland
| | - Bei Li
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland
| | - Irina Abakumova
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland
| | - Rita Moos
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland
| | - Petra Schwarz
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland
| | - Elisabeth J Rushing
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland
| | - Marco Colonna
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA
| | - Adriano Aguzzi
- Institute of Neuropathology, University Hospital Zurich, Zurich, Switzerland.
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Ortega-Cubero S, Lorenzo-Betancor O, Lorenzo E, Agúndez JAG, Jiménez-Jiménez FJ, Ross OA, Wurster I, Mielke C, Lin JJ, Coria F, Clarimon J, Ezquerra M, Brighina L, Annesi G, Alonso-Navarro H, García-Martin E, Gironell A, Marti MJ, Yueh KC, Wszolek ZK, Sharma M, Berg D, Krüger R, Pastor MA, Pastor P. TREM2 R47H variant and risk of essential tremor: a cross-sectional international multicenter study. Parkinsonism Relat Disord 2014; 21:306-9. [PMID: 25585992 DOI: 10.1016/j.parkreldis.2014.12.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 12/07/2014] [Accepted: 12/10/2014] [Indexed: 01/22/2023]
Abstract
INTRODUCTION Essential tremor (ET) is the most frequent movement disorder in adults. Its pathophysiology is not clearly understood, however there is growing evidence showing common etiologic factors with other neurodegenerative disorders such as Alzheimer's and Parkinson's diseases (AD, PD). Recently, a rare p.R47H substitution (rs75932628) in the TREM2 protein (triggering receptor expressed on myeloid cells 2; OMIM: *605086) has been proposed as a risk factor for AD, PD and amyotrophic lateral sclerosis (ALS). The objective of the study was to determine whether TREM2 p.R47H allele is also a risk factor for developing ET. METHODS This was a cross-sectional multicenter international study. An initial case-control cohort from Spain (n = 456 ET, n = 2715 controls) was genotyped. In a replication phase, a case-control series (n = 897 ET, n = 1449 controls) from different populations (Italy, Germany, North-America and Taiwan) was studied. Owed to the rarity of the variant, published results on p.R47H allele frequency from 14777 healthy controls from European, North American or Chinese descent were additionally considered. The main outcome measure was p.R47H (rs75932628) allelic frequency. RESULTS There was a significant association between TREM2 p.R47H variant and ET in the Spanish cohort (odds ratio [OR], 5.97; 95% CI, 1.203-29.626; p = 0.042), but it was not replicated in other populations. CONCLUSIONS These results argue in favor of population-specific differences in the allelic distribution and suggest that p.R47H (rs75932628) variant may contribute to the susceptibility of ET in Spanish population. However, taking into account the very low frequency of p.R47H, further confirmatory analyses of larger ET series are needed.
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Affiliation(s)
- Sara Ortega-Cubero
- Neurogenetics Laboratory, Division of Neurosciences, Center for Applied Medical Research, University of Navarra (CIMA), Pamplona, Spain; Department of Neurology, Clínica Universidad de Navarra, University of Navarra School of Medicine, Pamplona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, CIBERNED, Instituto de Salud Carlos III, Madrid, Spain
| | | | - Elena Lorenzo
- Neurogenetics Laboratory, Division of Neurosciences, Center for Applied Medical Research, University of Navarra (CIMA), Pamplona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, CIBERNED, Instituto de Salud Carlos III, Madrid, Spain
| | - José A G Agúndez
- Department of Pharmacology, University of Extremadura, Cáceres, Spain
| | | | - Owen A Ross
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL, USA
| | - Isabel Wurster
- Department for Neurodegenerative Diseases (DZNE), Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Carina Mielke
- Department for Neurodegenerative Diseases (DZNE), Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Juei-Jueng Lin
- Department of Neurology, Chushang Show-Chwan Hospital, Nantou, Taiwan; Department of Neurology, Chung-Shan Medical University Hospital, Taichung, Taiwan
| | - Francisco Coria
- Department of Neurology, Son Espases University Hospital, Mallorca, Spain
| | - Jordi Clarimon
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, CIBERNED, Instituto de Salud Carlos III, Madrid, Spain; Neurology Department, Institut d'Investigacions Biomediques Sant Pau, Hospital de Sant Pau, Universitat Autónoma de Barcelona, Barcelona, Spain
| | - Mario Ezquerra
- Parkinson's Disease and Movement Disorders Unit, Neurology Service, Institut Clinic de Neurociencies, Hospital Clinic de Barcelona, CIBERNED, Barcelona, Spain
| | - Laura Brighina
- Department of Neurology, San Gerardo Hospital, Milan Center for Neuroscience, University of Milano-Bicocca, Monza, Italy
| | - Grazia Annesi
- Section of Neuroimaging, Institute of Molecular Bioimaging and Physiology, National Research Council, Catanzaro, Italy
| | | | - Elena García-Martin
- Department of Biochemistry of Molecular Biology, University of Extremadura, Cáceres, Spain
| | - Alex Gironell
- Movement Disorders Unit, Department of Neurology, Hospital de Sant Pau, Universitat Autónoma de Barcelona, Barcelona, Spain
| | - Maria J Marti
- Parkinson's Disease and Movement Disorders Unit, Neurology Service, Institut Clinic de Neurociencies, Hospital Clinic de Barcelona, CIBERNED, Barcelona, Spain
| | - Kuo-Chu Yueh
- Department of Neurology, Chushang Show-Chwan Hospital, Nantou, Taiwan
| | | | - Manu Sharma
- Department for Neurodegenerative Diseases (DZNE), Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Daniela Berg
- Department for Neurodegenerative Diseases (DZNE), Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Rejko Krüger
- Department for Neurodegenerative Diseases (DZNE), Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany; Luxembourg Center for Systems Biomedicine, University of Luxembourg and Centre Hospitalier de Luxembourg, Luxembourg
| | - Maria A Pastor
- Department of Neurology, Clínica Universidad de Navarra, University of Navarra School of Medicine, Pamplona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, CIBERNED, Instituto de Salud Carlos III, Madrid, Spain; Neuroimaging Laboratory, Division of Neurosciences, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Pau Pastor
- Neurogenetics Laboratory, Division of Neurosciences, Center for Applied Medical Research, University of Navarra (CIMA), Pamplona, Spain; Department of Neurology, Clínica Universidad de Navarra, University of Navarra School of Medicine, Pamplona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas, CIBERNED, Instituto de Salud Carlos III, Madrid, Spain; Department of Neurology, Hospital Universitari Mutua de Terrassa, Terrassa, Barcelona, Spain.
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