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Donato L, Mordà D, Scimone C, Alibrandi S, D’Angelo R, Sidoti A. Bridging Retinal and Cerebral Neurodegeneration: A Focus on Crosslinks between Alzheimer-Perusini's Disease and Retinal Dystrophies. Biomedicines 2023; 11:3258. [PMID: 38137479 PMCID: PMC10741418 DOI: 10.3390/biomedicines11123258] [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: 11/01/2023] [Revised: 12/02/2023] [Accepted: 12/07/2023] [Indexed: 12/24/2023] Open
Abstract
In the early stages of Alzheimer-Perusini's disease (AD), individuals often experience vision-related issues such as color vision impairment, reduced contrast sensitivity, and visual acuity problems. As the disease progresses, there is a connection with glaucoma and age-related macular degeneration (AMD) leading to retinal cell death. The retina's involvement suggests a link with the hippocampus, where most AD forms start. A thinning of the retinal nerve fiber layer (RNFL) due to the loss of retinal ganglion cells (RGCs) is seen as a potential AD diagnostic marker using electroretinography (ERG) and optical coherence tomography (OCT). Amyloid beta fragments (Aβ), found in the eye's vitreous and aqueous humor, are also present in the cerebrospinal fluid (CSF) and accumulate in the retina. Aβ is known to cause tau hyperphosphorylation, leading to its buildup in various retinal layers. However, diseases like AD are now seen as mixed proteinopathies, with deposits of the prion protein (PrP) and α-synuclein found in affected brains and retinas. Glial cells, especially microglial cells, play a crucial role in these diseases, maintaining immunoproteostasis. Studies have shown similarities between retinal and brain microglia in terms of transcription factor expression and morphotypes. All these findings constitute a good start to achieving better comprehension of neurodegeneration in both the eye and the brain. New insights will be able to bring the scientific community closer to specific disease-modifying therapies.
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Affiliation(s)
- Luigi Donato
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
- Department of Biomolecular Strategies, Genetics, Cutting-Edge Therapies, Euro-Mediterranean Institute of Science and Technology (I.E.ME.S.T.), 90139 Palermo, Italy;
| | - Domenico Mordà
- Department of Biomolecular Strategies, Genetics, Cutting-Edge Therapies, Euro-Mediterranean Institute of Science and Technology (I.E.ME.S.T.), 90139 Palermo, Italy;
- Department of Veterinary Sciences, University of Messina, 98122 Messina, Italy
| | - Concetta Scimone
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
- Department of Biomolecular Strategies, Genetics, Cutting-Edge Therapies, Euro-Mediterranean Institute of Science and Technology (I.E.ME.S.T.), 90139 Palermo, Italy;
| | - Simona Alibrandi
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
- Department of Biomolecular Strategies, Genetics, Cutting-Edge Therapies, Euro-Mediterranean Institute of Science and Technology (I.E.ME.S.T.), 90139 Palermo, Italy;
| | - Rosalia D’Angelo
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
| | - Antonina Sidoti
- Department of Biomedical and Dental Sciences and Morphofunctional Imaging, Division of Medical Biotechnologies and Preventive Medicine, University of Messina, 98122 Messina, Italy; (L.D.); (C.S.); (R.D.); (A.S.)
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2
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Lee JI, Choi JH, Kwon TW, Jo HS, Kim DG, Ko SG, Song GJ, Cho IH. Neuroprotective effects of bornyl acetate on experimental autoimmune encephalomyelitis via anti-inflammatory effects and maintaining blood-brain-barrier integrity. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2023; 112:154569. [PMID: 36842217 DOI: 10.1016/j.phymed.2022.154569] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 09/05/2022] [Accepted: 11/19/2022] [Indexed: 06/18/2023]
Abstract
BACKGROUND Bornyl acetate (BA), a chemical component of essential oil in the Pinus family, has yet to be actively studies in terms of its therapeutic effect on numerous diseases, including autoimmune diseases. PURPOSE This study aimed to investigate the pharmacological effects and molecular mechanisms of BA on myelin oligodendrocyte glycoprotein (MOG35-55)-induced experimental autoimmune encephalomyelitis (EAE) mice in an animal model of multiple sclerosis (MS), a representative autoimmune disease in central nervous system. METHODS BA (100, 200, or 400 mg/kg) was orally treated to EAE mice once daily for 30 days after immunization for the behavioral test and for the 16th-18th days for the histopathological and molecular analyses, from the onset stage (8th day) of EAE symptoms. RESULTS BA mitigated behavioral dysfunction (motor disability) and demyelination in the spinal cord that were associated with the down-regulation of representative pro-inflammatory cytokines (interleukin (IL)-1 beta, IL-6, and tumor necrosis factor-alpha), enzymes (cyclooxygenase-2 and inducible nitric oxide synthase), and chemokines (monocyte chemotactic protein-1, macrophage inflammatory protein-1 alpha, and regulated on activation), and decreased infiltration of microglia (CD11b+/CD45+(low)) and macrophages (CD11b+/CD45+(high)). The anti-inflammatory effect of BA was related to the inhibition of mitogen-activated protein kinases and nuclear factor-kappa B pathways. BA also reduced the recruitment/infiltration rates of CD4+ T, Th1, and Th17 cells into the spinal cords of EAE mice, which was related to reduced blood-spinal cord barrier (BSCB) disruption. CONCLUSION These findings strongly suggest that BA may alleviate EAE due to its anti-inflammatory and BSCB protective activities. This indicates that BA is a potential therapeutic agent for treating autoimmune demyelinating diseases including MS.
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Affiliation(s)
- Joon-Il Lee
- Department of Convergence Medical Science, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Jong-Hee Choi
- Department of Convergence Medical Science, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Tae-Woo Kwon
- Department of Convergence Medical Science, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Hyo-Sung Jo
- Department of Convergence Medical Science, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Do-Geun Kim
- Dementia Research Group, Korea Brain Research Institute, Daegu 41068, Republic of Korea
| | - Seong-Gyu Ko
- Korean Medicine-based Drug Repositioning Cancer Research Center, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Gyun Jee Song
- Department of Medical Science, Catholic Kwandong University College of Medicine, Gangneung, Gangwon-do 25601, Republic of Korea
| | - Ik-Hyun Cho
- Department of Convergence Medical Science, College of Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea; Department of Science in Korean Medicine, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea; Institute of Convergence Korean Medicine, Kyung Hee University, Seoul 02447, Republic of Korea.
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3
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van den Bosch AMR, Hümmert S, Steyer A, Ruhwedel T, Hamann J, Smolders J, Nave KA, Stadelmann C, Kole MHP, Möbius W, Huitinga I. Ultrastructural Axon-Myelin Unit Alterations in Multiple Sclerosis Correlate with Inflammation. Ann Neurol 2022; 93:856-870. [PMID: 36565265 DOI: 10.1002/ana.26585] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/13/2022] [Accepted: 12/17/2022] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Changes in the normal-appearing white matter (NAWM) in multiple sclerosis (MS) may contribute to disease progression. Here, we systematically quantified ultrastructural and subcellular characteristics of the axon-myelin unit in MS NAWM and determined how this correlates with low-grade inflammation. METHODS Human brain tissue obtained with short postmortem delay and fixation at autopsy enables systematic quantification of ultrastructural characteristics. In this study, we performed high-resolution immunohis tochemistry and quantitative transmission electron microscopy to study inflammation and ultrastructural characteristics of the axon-myelin unit in MS NAWM (n = 8) and control white matter (WM) in the optic nerve. RESULTS In the MS NAWM, there were more activated and phagocytic microglia cells (HLA+ P2RY12- and Iba1+ CD68+ ) and more T cells (CD3+ ) compared to control WM, mainly located in the perivascular space. In MS NAWM compared to control WM, there were, as expected, longer paranodes and juxtaparanodes and larger overlap between paranodes and juxtaparanodes. There was less compact myelin wrapping, a lower g-ratio, and a higher frequency of axonal mitochondria. Changes in myelin and axonal mitochondrial frequency correlated positively with the number of active and phagocytic microglia and lymphocytes in the optic nerve. INTERPRETATION These data suggest that in MS NAWM myelin detachment and uncompact myelin wrapping occurs, potassium channels are unmasked at the nodes of Ranvier, and axonal energy demand is increased, or mitochondrial transport is stagnated, accompanied by increased presence of activated and phagocytic microglia and T cells. These subclinical alterations to the axon-myelin unit in MS NAWM may contribute to disease progression. ANN NEUROL 2023.
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Affiliation(s)
- Aletta M R van den Bosch
- Department of Neuroimmunology, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Amsterdam, the Netherlands
| | - Sophie Hümmert
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Anna Steyer
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Torben Ruhwedel
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Jörg Hamann
- Department of Neuroimmunology, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Amsterdam, the Netherlands.,Department of Experimental Immunology, Amsterdam Institute for Infection and Immunity, Amsterdam University Medical Centers, Amsterdam, the Netherlands
| | - Joost Smolders
- Department of Neuroimmunology, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Amsterdam, the Netherlands.,Department of Neurology and Immunology, Multiple Sclerosis Center ErasMS, Erasmus Medical Center, Rotterdam, the Netherlands
| | - Klaus-Armin Nave
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Christine Stadelmann
- Department of Neuropathology, University Medical Center Göttingen, Göttingen, Germany
| | - Maarten H P Kole
- Department of Axonal Signaling, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Amsterdam, the Netherlands.,Cell Biology, Neurobiology, and Biophysics, Department of Biology, Faculty of Science, University of Utrecht, Utrecht, the Netherlands
| | - Wiebke Möbius
- Department of Neurogenetics, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Inge Huitinga
- Department of Neuroimmunology, Netherlands Institute for Neuroscience, Royal Netherlands Academy for Arts and Sciences, Amsterdam, the Netherlands.,Center for Neuroscience, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, Amsterdam, the Netherlands
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Yang D, Wang X, Zhang L, Fang Y, Zheng Q, Liu X, Yu W, Chen S, Ying J, Hua F. Lipid metabolism and storage in neuroglia: role in brain development and neurodegenerative diseases. Cell Biosci 2022; 12:106. [PMID: 35831869 PMCID: PMC9277953 DOI: 10.1186/s13578-022-00828-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 06/05/2022] [Indexed: 11/13/2022] Open
Abstract
The importance of neuroglia in maintaining normal brain function under physiological and pathological conditions has been supported by growing evidence in recent years. The most important issues regarding glial metabolism and function include the cooperation between glial populations and neurons, morphological and functional changes in pathological states, and the role in the onset and progression of neurodegenerative diseases. Although lipid accumulation and further lipid droplet production in neurodegenerative disease brain models have been observed for a long time, the dynamic development of brain lipid droplet research in recent years suggests its role in the development and progression of neurodegenerative diseases was previously underestimated. First recognized as organelles of lipid storage, lipid droplets (LDs) have emerged as an important organelle in metabolic diseases, inflammation, and host defense. Dynamic changes in lipid metabolism within neurons and glial cells resulting in lipid accumulation and lipid droplet formation are present in brain models of various neurodegenerative diseases, yet their role in the brain remains largely unexplored. This paper first reviews the metabolism and accumulation of several major lipids in the brain and discusses the regulation of lipid accumulation in different types of brain cells. We explore the potential role of intracellular lipid accumulation in the pathogenesis of neurodegeneration, starting from lipid metabolism and LDs biogenesis in glial cells, and discuss several pathological factors that promote lipid droplet formation, mainly focusing on oxidative stress, energy metabolism and glial cell-neuron coupling, which are closely related to the etiology and progression of neurodegenerative diseases. Finally, the directions and challenges of intracellular lipid metabolism in glial cells in neurodegeneration are discussed.
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Maguire E, Connor-Robson N, Shaw B, O’Donoghue R, Stöberl N, Hall-Roberts H. Assaying Microglia Functions In Vitro. Cells 2022; 11:3414. [PMID: 36359810 PMCID: PMC9654693 DOI: 10.3390/cells11213414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 10/20/2022] [Accepted: 10/25/2022] [Indexed: 08/27/2023] Open
Abstract
Microglia, the main immune modulators of the central nervous system, have key roles in both the developing and adult brain. These functions include shaping healthy neuronal networks, carrying out immune surveillance, mediating inflammatory responses, and disposing of unwanted material. A wide variety of pathological conditions present with microglia dysregulation, highlighting the importance of these cells in both normal brain function and disease. Studies into microglial function in the context of both health and disease thus have the potential to provide tremendous insight across a broad range of research areas. In vitro culture of microglia, using primary cells, cell lines, or induced pluripotent stem cell derived microglia, allows researchers to generate reproducible, robust, and quantifiable data regarding microglia function. A broad range of assays have been successfully developed and optimised for characterizing microglial morphology, mediation of inflammation, endocytosis, phagocytosis, chemotaxis and random motility, and mediation of immunometabolism. This review describes the main functions of microglia, compares existing protocols for measuring these functions in vitro, and highlights common pitfalls and future areas for development. We aim to provide a comprehensive methodological guide for researchers planning to characterise microglial functions within a range of contexts and in vitro models.
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Affiliation(s)
- Emily Maguire
- UK Dementia Research Institute (UK DRI), School of Medicine, Cardiff University, Cardiff CF10 3AT, UK
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Guo L, Choi S, Bikkannavar P, Cordeiro MF. Microglia: Key Players in Retinal Ageing and Neurodegeneration. Front Cell Neurosci 2022; 16:804782. [PMID: 35370560 PMCID: PMC8968040 DOI: 10.3389/fncel.2022.804782] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 02/11/2022] [Indexed: 12/20/2022] Open
Abstract
Microglia are the resident immune cells of the central nervous system (CNS) and play a key role in maintaining the normal function of the retina and brain. During early development, microglia migrate into the retina, transform into a highly ramified phenotype, and scan their environment constantly. Microglia can be activated by any homeostatic disturbance that may endanger neurons and threaten tissue integrity. Once activated, the young microglia exhibit a high diversity in their phenotypes as well as their functions, which relate to either beneficial or harmful consequences. Microglial activation is associated with the release of cytokines, chemokines, and growth factors that can determine pathological outcomes. As the professional phagocytes in the retina, microglia are responsible for the clearance of pathogens, dead cells, and protein aggregates. However, their phenotypic diversity and phagocytic capacity is compromised with ageing. This may result in the accumulation of protein aggregates and myelin debris leading to retinal neuroinflammation and neurodegeneration. In this review, we describe microglial phenotypes and functions in the context of the young and ageing retina, and the mechanisms underlying changes in ageing. Additionally, we review microglia-mediated retinal neuroinflammation and discuss the mechanisms of microglial involvement in retinal neurodegenerative diseases.
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Affiliation(s)
- Li Guo
- Institute of Ophthalmology, University College London, London, United Kingdom
- *Correspondence: Li Guo,
| | - Soyoung Choi
- Institute of Ophthalmology, University College London, London, United Kingdom
| | | | - M. Francesca Cordeiro
- Institute of Ophthalmology, University College London, London, United Kingdom
- Imperial College Ophthalmology Research Group, Imperial College London, London, United Kingdom
- M. Francesca Cordeiro,
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Gumbs SBH, Kübler R, Gharu L, Schipper PJ, Borst AL, Snijders GJLJ, Ormel PR, van Berlekom AB, Wensing AMJ, de Witte LD, Nijhuis M. Human microglial models to study HIV infection and neuropathogenesis: a literature overview and comparative analyses. J Neurovirol 2022; 28:64-91. [PMID: 35138593 PMCID: PMC9076745 DOI: 10.1007/s13365-021-01049-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 12/03/2021] [Accepted: 12/18/2021] [Indexed: 02/08/2023]
Abstract
HIV persistence in the CNS despite antiretroviral therapy may cause neurological disorders and poses a critical challenge for HIV cure. Understanding the pathobiology of HIV-infected microglia, the main viral CNS reservoir, is imperative. Here, we provide a comprehensive comparison of human microglial culture models: cultured primary microglia (pMG), microglial cell lines, monocyte-derived microglia (MDMi), stem cell-derived microglia (iPSC-MG), and microglia grown in 3D cerebral organoids (oMG) as potential model systems to advance HIV research on microglia. Functional characterization revealed phagocytic capabilities and responsiveness to LPS across all models. Microglial transcriptome profiles of uncultured pMG showed the highest similarity to cultured pMG and oMG, followed by iPSC-MG and then MDMi. Direct comparison of HIV infection showed a striking difference, with high levels of viral replication in cultured pMG and MDMi and relatively low levels in oMG resembling HIV infection observed in post-mortem biopsies, while the SV40 and HMC3 cell lines did not support HIV infection. Altogether, based on transcriptional similarities to uncultured pMG and susceptibility to HIV infection, MDMi may serve as a first screening tool, whereas oMG, cultured pMG, and iPSC-MG provide more representative microglial culture models for HIV research. The use of current human microglial cell lines (SV40, HMC3) is not recommended.
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Affiliation(s)
- Stephanie B H Gumbs
- Translational Virology, Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Raphael Kübler
- Translational Virology, Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
- Department of Psychiatry, Icahn School of Medicine, New York, NY, USA
| | - Lavina Gharu
- Translational Virology, Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Pauline J Schipper
- Translational Virology, Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Anne L Borst
- Translational Virology, Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Gijsje J L J Snijders
- Department of Psychiatry, Icahn School of Medicine, New York, NY, USA
- Department of Psychiatry, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Paul R Ormel
- Department of Psychiatry, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Amber Berdenis van Berlekom
- Department of Psychiatry, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands
- Department of Translational Neuroscience, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Annemarie M J Wensing
- Translational Virology, Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Lot D de Witte
- Department of Psychiatry, Icahn School of Medicine, New York, NY, USA
- Department of Psychiatry, University Medical Center Utrecht, Brain Center, Utrecht University, Utrecht, The Netherlands
| | - Monique Nijhuis
- Translational Virology, Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, The Netherlands.
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Berdowski WM, van der Linde HC, Breur M, Oosterhof N, Beerepoot S, Sanderson L, Wijnands LI, de Jong P, Tsai-Meu-Chong E, de Valk W, de Witte M, van IJcken WFJ, Demmers J, van der Knaap MS, Bugiani M, Wolf NI, van Ham TJ. Dominant-acting CSF1R variants cause microglial depletion and altered astrocytic phenotype in zebrafish and adult-onset leukodystrophy. Acta Neuropathol 2022; 144:211-239. [PMID: 35713703 PMCID: PMC9288387 DOI: 10.1007/s00401-022-02440-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 05/16/2022] [Accepted: 05/16/2022] [Indexed: 11/26/2022]
Abstract
Tissue-resident macrophages of the brain, including microglia, are implicated in the pathogenesis of various CNS disorders and are possible therapeutic targets by their chemical depletion or replenishment by hematopoietic stem cell therapy. Nevertheless, a comprehensive understanding of microglial function and the consequences of microglial depletion in the human brain is lacking. In human disease, heterozygous variants in CSF1R, encoding the Colony-stimulating factor 1 receptor, can lead to adult-onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP) possibly caused by microglial depletion. Here, we investigate the effects of ALSP-causing CSF1R variants on microglia and explore the consequences of microglial depletion in the brain. In intermediate- and late-stage ALSP post-mortem brain, we establish that there is an overall loss of homeostatic microglia and that this is predominantly seen in the white matter. By introducing ALSP-causing missense variants into the zebrafish genomic csf1ra locus, we show that these variants act dominant negatively on the number of microglia in vertebrate brain development. Transcriptomics and proteomics on relatively spared ALSP brain tissue validated a downregulation of microglia-associated genes and revealed elevated astrocytic proteins, possibly suggesting involvement of astrocytes in early pathogenesis. Indeed, neuropathological analysis and in vivo imaging of csf1r zebrafish models showed an astrocytic phenotype associated with enhanced, possibly compensatory, endocytosis. Together, our findings indicate that microglial depletion in zebrafish and human disease, likely as a consequence of dominant-acting pathogenic CSF1R variants, correlates with altered astrocytes. These findings underscore the unique opportunity CSF1R variants provide to gain insight into the roles of microglia in the human brain, and the need to further investigate how microglia, astrocytes, and their interactions contribute to white matter homeostasis.
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Affiliation(s)
- Woutje M. Berdowski
- grid.5645.2000000040459992XDepartment of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Herma C. van der Linde
- grid.5645.2000000040459992XDepartment of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Marjolein Breur
- grid.12380.380000 0004 1754 9227Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands ,grid.12380.380000 0004 1754 9227Amsterdam Neuroscience, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands ,grid.484519.5Department of Pathology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - Nynke Oosterhof
- grid.4494.d0000 0000 9558 4598European Research Institute for the Biology of Ageing (ERIBA), University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Shanice Beerepoot
- grid.12380.380000 0004 1754 9227Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands ,grid.12380.380000 0004 1754 9227Amsterdam Neuroscience, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Leslie Sanderson
- grid.5645.2000000040459992XDepartment of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Lieve I. Wijnands
- grid.5645.2000000040459992XDepartment of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Patrick de Jong
- grid.5645.2000000040459992XDepartment of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Elisa Tsai-Meu-Chong
- grid.5645.2000000040459992XDepartment of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Walter de Valk
- grid.5645.2000000040459992XDepartment of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - Moniek de Witte
- grid.7692.a0000000090126352Hematology Department, University Medical Center, Utrecht, The Netherlands
| | - Wilfred F. J. van IJcken
- grid.5645.2000000040459992XCenter for Biomics, Erasmus MC University Medical Center, Rotterdam, The Netherlands
| | - Jeroen Demmers
- grid.5645.2000000040459992XProteomics Center, Erasmus University Medical Center, Wytemaweg 80, 3015 CN Rotterdam, The Netherlands
| | - Marjo S. van der Knaap
- grid.12380.380000 0004 1754 9227Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands ,grid.12380.380000 0004 1754 9227Amsterdam Neuroscience, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Marianna Bugiani
- grid.12380.380000 0004 1754 9227Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands ,grid.12380.380000 0004 1754 9227Amsterdam Neuroscience, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands ,grid.484519.5Department of Pathology, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands
| | - Nicole I. Wolf
- grid.12380.380000 0004 1754 9227Department of Child Neurology, Amsterdam Leukodystrophy Center, Emma Children’s Hospital, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands ,grid.12380.380000 0004 1754 9227Amsterdam Neuroscience, Amsterdam University Medical Centers, Vrije Universiteit, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | - Tjakko J. van Ham
- grid.5645.2000000040459992XDepartment of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, The Netherlands
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Standiford MM, Grund EM, Howe CL. Citrullinated myelin induces microglial TNFα and inhibits endogenous repair in the cuprizone model of demyelination. J Neuroinflammation 2021; 18:305. [PMID: 34961522 PMCID: PMC8711191 DOI: 10.1186/s12974-021-02360-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Accepted: 12/15/2021] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Microglia are the primary phagocytes of the central nervous system and are responsible for removing damaged myelin following demyelination. Previous investigations exploring the consequences of myelin phagocytosis on microglial activation overlooked the biochemical modifications present on myelin debris. Such modifications, including citrullination, are increased within the inflammatory environment of multiple sclerosis lesions. METHODS Mouse cortical myelin isolated by ultracentrifugation was citrullinated ex vivo by incubation with the calcium-dependent peptidyl arginine deiminase PAD2. Demyelination was induced by 6 weeks of cuprizone (0.3%) treatment and spontaneous repair was initiated by reversion to normal chow. Citrullinated or unmodified myelin was injected into the primary motor cortex above the cingulum bundle at the time of reversion to normal chow and the consequent impact on remyelination was assessed by measuring the surface area of myelin basic protein-positive fibers in the cortex 3 weeks later. Microglial responses to myelin were characterized by measuring cytokine release, assessing flow cytometric markers of microglial activation, and RNAseq profiling of transcriptional changes. RESULTS Citrullinated myelin induced a unique microglial response marked by increased tumor necrosis factor α (TNFα) production both in vitro and in vivo. This response was not induced by unmodified myelin. Injection of citrullinated myelin but not unmodified myelin into the cortex of cuprizone-demyelinated mice significantly inhibited spontaneous remyelination. Antibody-mediated neutralization of TNFα blocked this effect and restored remyelination to normal levels. CONCLUSIONS These findings highlight the role of post-translation modifications such as citrullination in the determination of microglial activation in response to myelin during demyelination. The inhibition of endogenous repair induced by citrullinated myelin and the reversal of this effect by neutralization of TNFα may have implications for therapeutic approaches to patients with inflammatory demyelinating disorders.
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Affiliation(s)
- Miranda M Standiford
- Neuroscience PhD Program, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, 55905, USA.,Translational Neuroimmunology Lab, Mayo Clinic, Rochester, MN, 55905, USA.,Multiple Sclerosis and Neurorepair Research Unit, Biogen, Cambridge, MA, 02142, USA
| | - Ethan M Grund
- Neuroscience PhD Program, Mayo Clinic Graduate School of Biomedical Sciences, Rochester, MN, 55905, USA.,Translational Neuroimmunology Lab, Mayo Clinic, Rochester, MN, 55905, USA
| | - Charles L Howe
- Translational Neuroimmunology Lab, Mayo Clinic, Rochester, MN, 55905, USA. .,Division of Experimental Neurology, Department of Neurology, Mayo Clinic, Rochester, MN, 55905, USA. .,Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, Rochester, MN, 55905, USA.
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10
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Choi S, Guo L, Cordeiro MF. Retinal and Brain Microglia in Multiple Sclerosis and Neurodegeneration. Cells 2021; 10:cells10061507. [PMID: 34203793 PMCID: PMC8232741 DOI: 10.3390/cells10061507] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 05/28/2021] [Accepted: 06/11/2021] [Indexed: 12/24/2022] Open
Abstract
Microglia are the resident immune cells of the central nervous system (CNS), including the retina. Similar to brain microglia, retinal microglia are responsible for retinal surveillance, rapidly responding to changes in the environment by altering morphotype and function. Microglia become activated in inflammatory responses in neurodegenerative diseases, including multiple sclerosis (MS). When activated by stress stimuli, retinal microglia change their morphology and activity, with either beneficial or harmful consequences. In this review, we describe characteristics of CNS microglia, including those in the retina, with a focus on their morphology, activation states and function in health, ageing, MS and other neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, glaucoma and retinitis pigmentosa, to highlight their activity in disease. We also discuss contradictory findings in the literature and the potential ways of reducing inconsistencies in future by using standardised methodology, e.g., automated algorithms, to enable a more comprehensive understanding of this exciting area of research.
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Affiliation(s)
- Soyoung Choi
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; (S.C.); (L.G.)
| | - Li Guo
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; (S.C.); (L.G.)
| | - Maria Francesca Cordeiro
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; (S.C.); (L.G.)
- ICORG, Imperial College London, London NW1 5QH, UK
- Correspondence:
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11
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den Dunnen J, Mes L, Hoepel W, Smolders J. Multiple sclerosis: why we should focus on both sides of the (auto)antibody. Neural Regen Res 2021; 16:2422-2424. [PMID: 33907027 PMCID: PMC8374557 DOI: 10.4103/1673-5374.313045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Affiliation(s)
- Jeroen den Dunnen
- Amsterdam Rheumatology and Immunology Center, Department of Rheumatology and Clinical Immunology; Department of Experimental Immunology, Amsterdam Institute for Infection and Immunity, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Lynn Mes
- Amsterdam Rheumatology and Immunology Center, Department of Rheumatology and Clinical Immunology; Department of Experimental Immunology; Department of Medical Microbiology, Amsterdam institute for Infection and Immunity, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Willianne Hoepel
- Amsterdam Rheumatology and Immunology Center, Department of Rheumatology and Clinical Immunology; Department of Experimental Immunology, Amsterdam Institute for Infection and Immunity, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Joost Smolders
- Neuroimmunology Research group, Netherlands Institute for Neuroscience, Amsterdam; MS Center ErasMS, Departments of Neurology and Immunology, Erasmus Medical Center, Rotterdam, The Netherlands
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12
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Borucki DM, Toutonji A, Couch C, Mallah K, Rohrer B, Tomlinson S. Complement-Mediated Microglial Phagocytosis and Pathological Changes in the Development and Degeneration of the Visual System. Front Immunol 2020; 11:566892. [PMID: 33072106 PMCID: PMC7541817 DOI: 10.3389/fimmu.2020.566892] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 08/17/2020] [Indexed: 12/21/2022] Open
Abstract
The focus of this review is the role of complement-mediated phagocytosis in retinal and neurological diseases affecting the visual system. Complement activation products opsonize synaptic material on neurons for phagocytic removal, which is a normal physiological process during development, but a pathological process in several neurodegenerative diseases and conditions. We discuss the role of complement in the refinement and elimination of synapses in the retina and lateral geniculate nucleus, both during development and in disease states. How complement and aberrant phagocytosis promotes injury to the visual system is discussed primarily in the context of multiple sclerosis, where it has been extensively studied, although the role of complement in visual dysfunction in other diseases such as stroke and traumatic brain injury is also highlighted. Retinal diseases are also covered, with a focus on glaucoma and age-related macular degeneration. Finally, we discuss the potential of complement inhibitory strategies to treat diseases affecting the visual system.
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Affiliation(s)
- Davis M. Borucki
- Medical Scientist Training Program, Medical University of South Carolina, Charleston, SC, United States
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, United States
| | - Amer Toutonji
- Medical Scientist Training Program, Medical University of South Carolina, Charleston, SC, United States
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, United States
| | - Christine Couch
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
- Department of Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States
| | - Khalil Mallah
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
| | - Baerbel Rohrer
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, United States
- Department of Ophthalmology, Medical University of South Carolina, Charleston, SC, United States
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States
| | - Stephen Tomlinson
- Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, United States
- Ralph H. Johnson VA Medical Center, Charleston, SC, United States
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13
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van der Poel M, Hoepel W, Hamann J, Huitinga I, Dunnen JD. IgG Immune Complexes Break Immune Tolerance of Human Microglia. THE JOURNAL OF IMMUNOLOGY 2020; 205:2511-2518. [PMID: 32967931 DOI: 10.4049/jimmunol.2000130] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 08/31/2020] [Indexed: 12/26/2022]
Abstract
Microglia are phagocytic cells involved in homeostasis of the brain and are key players in the pathogenesis of multiple sclerosis (MS). A hallmark of MS diagnosis is the presence of IgG Abs, which appear as oligoclonal bands in the cerebrospinal fluid. In this study, we demonstrate that myelin obtained post mortem from 8 out of 11 MS brain donors is bound by IgG Abs. Importantly, we show that IgG immune complexes strongly potentiate activation of primary human microglia by breaking their tolerance for microbial stimuli, such as LPS and Poly I:C, resulting in increased production of key proinflammatory cytokines, such as TNF and IL-1β. We identified FcγRI and FcγRIIa as the two main responsible IgG receptors for the breaking of immune tolerance of microglia. Combined, these data indicate that IgG immune complexes potentiate inflammation by human microglia, which may play an important role in MS-associated inflammation and the formation of demyelinating lesions.
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Affiliation(s)
- Marlijn van der Poel
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, the Netherlands
| | - Willianne Hoepel
- Department of Experimental Immunology, Amsterdam Infection and Immunity Institute, University Medical Centers, 1105 AZ Amsterdam, the Netherlands.,Amsterdam Rheumatology and Immunology Center, Department of Rheumatology and Clinical Immunology, Amsterdam University Medical Centers, 1105 AZ Amsterdam, the Netherlands; and
| | - Jörg Hamann
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, the Netherlands.,Department of Experimental Immunology, Amsterdam Infection and Immunity Institute, University Medical Centers, 1105 AZ Amsterdam, the Netherlands
| | - Inge Huitinga
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, 1105 BA Amsterdam, the Netherlands.,Swammerdam Institute for Life Sciences, University of Amsterdam, 1090 GE Amsterdam, the Netherlands
| | - Jeroen den Dunnen
- Department of Experimental Immunology, Amsterdam Infection and Immunity Institute, University Medical Centers, 1105 AZ Amsterdam, the Netherlands; .,Amsterdam Rheumatology and Immunology Center, Department of Rheumatology and Clinical Immunology, Amsterdam University Medical Centers, 1105 AZ Amsterdam, the Netherlands; and
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14
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Chausse B, Kakimoto PA, Kann O. Microglia and lipids: how metabolism controls brain innate immunity. Semin Cell Dev Biol 2020; 112:137-144. [PMID: 32807643 DOI: 10.1016/j.semcdb.2020.08.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/31/2020] [Accepted: 08/01/2020] [Indexed: 12/26/2022]
Abstract
Microglia are universal sensors of alterations in CNS physiology. These cells integrate complex molecular signals and undergo comprehensive phenotypical remodeling to adapt inflammatory responses. In the last years, single-cell analyses have revealed that microglia exhibit diverse phenotypes during development, growth and disease. Emerging evidence suggests that such phenotype transitions are mediated by reprogramming of cell metabolism. Indeed, metabolic pathways are distinctively altered in activated microglia and are central nodes controlling microglial responses. Microglial lipid metabolism has been specifically involved in the control of microglial activation and effector functions, such as migration, phagocytosis and inflammatory signaling, and minor disturbances in microglial lipid handling associates with altered brain function in disorders featuring neuroinflammation. In this review, we explore new and relevant aspects of microglial metabolism in health and disease. We give special focus on how different branches of lipid metabolism, such as lipid sensing, synthesis and oxidation, integrate and control essential aspects of microglial biology, and how disturbances in these processes associate with aging and the pathogenesis of, for instance, multiple sclerosis and Alzheimer's disease. Finally, challenges and advances in microglial lipid research are discussed.
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Affiliation(s)
- Bruno Chausse
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany.
| | - Pamela A Kakimoto
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, 05508-000, São Paulo, Brazil
| | - Oliver Kann
- Institute of Physiology and Pathophysiology, University of Heidelberg, D-69120 Heidelberg, Germany; Interdisciplinary Center for Neurosciences, University of Heidelberg, D-69120 Heidelberg, Germany
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15
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Gabandé‐Rodríguez E, Keane L, Capasso M. Microglial phagocytosis in aging and Alzheimer's disease. J Neurosci Res 2019; 98:284-298. [DOI: 10.1002/jnr.24419] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/20/2019] [Accepted: 03/08/2019] [Indexed: 01/24/2023]
Affiliation(s)
- Enrique Gabandé‐Rodríguez
- Department of Molecular Neuropathology Centro de Biología Molecular “Severo Ochoa” (CSIC‐UAM) Madrid Spain
| | - Lily Keane
- German Center for Neurodegenerative Diseases (DZNE) Bonn Germany
| | - Melania Capasso
- German Center for Neurodegenerative Diseases (DZNE) Bonn Germany
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16
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van der Poel M, Ulas T, Mizee MR, Hsiao CC, Miedema SSM, Adelia, Schuurman KG, Helder B, Tas SW, Schultze JL, Hamann J, Huitinga I. Transcriptional profiling of human microglia reveals grey-white matter heterogeneity and multiple sclerosis-associated changes. Nat Commun 2019; 10:1139. [PMID: 30867424 PMCID: PMC6416318 DOI: 10.1038/s41467-019-08976-7] [Citation(s) in RCA: 186] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 02/07/2019] [Indexed: 12/22/2022] Open
Abstract
Here we report the transcriptional profile of human microglia, isolated from normal-appearing grey matter (GM) and white matter (WM) of multiple sclerosis (MS) and non-neurological control donors, to find possible early changes related to MS pathology. Microglia show a clear region-specific profile, indicated by higher expression of type-I interferon genes in GM and higher expression of NF-κB pathway genes in WM. Transcriptional changes in MS microglia also differ between GM and WM. MS WM microglia show increased lipid metabolism gene expression, which relates to MS pathology since active MS lesion-derived microglial nuclei show similar altered gene expression. Microglia from MS GM show increased expression of genes associated with glycolysis and iron homeostasis, possibly reflecting microglia reacting to iron depositions. Except for ADGRG1/GPR56, expression of homeostatic genes, such as P2RY12 and TMEM119, is unaltered in normal-appearing MS tissue, demonstrating overall preservation of microglia homeostatic functions in the initiation phase of MS.
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Affiliation(s)
- Marlijn van der Poel
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA, Amsterdam, The Netherlands
| | - Thomas Ulas
- Genomics and Immunoregulation, LIMES Institute, University of Bonn, Carl-Troll-Straße 31, 53115, Bonn, Germany
| | - Mark R Mizee
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA, Amsterdam, The Netherlands
| | - Cheng-Chih Hsiao
- Department of Experimental Immunology, Amsterdam University Medical Centers, University of Amsterdam, Meibergdreef 9, 1105AZ, Amsterdam, The Netherlands
| | - Suzanne S M Miedema
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA, Amsterdam, The Netherlands
| | - Adelia
- Netherlands Brain Bank, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA, Amsterdam, The Netherlands
| | - Karianne G Schuurman
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA, Amsterdam, The Netherlands
| | - Boy Helder
- Department of Experimental Immunology, Amsterdam University Medical Centers, University of Amsterdam, Meibergdreef 9, 1105AZ, Amsterdam, The Netherlands
- Department of Clinical Immunology and Rheumatology, Amsterdam Rheumatology and Immunology Center, Amsterdam University Medical Centers, University of Amsterdam, Meibergdreef 9, 1105AZ, Amsterdam, The Netherlands
| | - Sander W Tas
- Department of Experimental Immunology, Amsterdam University Medical Centers, University of Amsterdam, Meibergdreef 9, 1105AZ, Amsterdam, The Netherlands
- Department of Clinical Immunology and Rheumatology, Amsterdam Rheumatology and Immunology Center, Amsterdam University Medical Centers, University of Amsterdam, Meibergdreef 9, 1105AZ, Amsterdam, The Netherlands
| | - Joachim L Schultze
- Genomics and Immunoregulation, LIMES Institute, University of Bonn, Carl-Troll-Straße 31, 53115, Bonn, Germany
- PRECISE Platform for Single Cell Genomics and Epigenomics, German Center for Neurodegenerative Diseases, University of Bonn, Sigmund-Freud-Street 27, 53127, Bonn, Germany
| | - Jörg Hamann
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA, Amsterdam, The Netherlands.
- Department of Experimental Immunology, Amsterdam University Medical Centers, University of Amsterdam, Meibergdreef 9, 1105AZ, Amsterdam, The Netherlands.
| | - Inge Huitinga
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA, Amsterdam, The Netherlands.
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17
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Grajchen E, Hendriks JJA, Bogie JFJ. The physiology of foamy phagocytes in multiple sclerosis. Acta Neuropathol Commun 2018; 6:124. [PMID: 30454040 PMCID: PMC6240956 DOI: 10.1186/s40478-018-0628-8] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 11/02/2018] [Indexed: 12/15/2022] Open
Abstract
Multiple sclerosis (MS) is a chronic disease of the central nervous system characterized by massive infiltration of immune cells, demyelination, and axonal loss. Active MS lesions mainly consist of macrophages and microglia containing abundant intracellular myelin remnants. Initial studies showed that these foamy phagocytes primarily promote MS disease progression by internalizing myelin debris, presenting brain-derived autoantigens, and adopting an inflammatory phenotype. However, more recent studies indicate that phagocytes can also adopt a beneficial phenotype upon myelin internalization. In this review, we summarize and discuss the current knowledge on the spatiotemporal physiology of foamy phagocytes in MS lesions, and elaborate on extrinsic and intrinsic factors regulating their behavior. In addition, we discuss and link the physiology of myelin-containing phagocytes to that of foamy macrophages in other disorders such atherosclerosis.
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Affiliation(s)
- Elien Grajchen
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium
| | - Jerome J A Hendriks
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium
| | - Jeroen F J Bogie
- Biomedical Research Institute, Hasselt University, Diepenbeek, Belgium/School of Life Sciences, Transnationale Universiteit Limburg, Diepenbeek, Belgium.
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18
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Human IgM antibody rHIgM22 promotes phagocytic clearance of myelin debris by microglia. Sci Rep 2018; 8:9392. [PMID: 29925848 PMCID: PMC6010437 DOI: 10.1038/s41598-018-27559-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 06/01/2018] [Indexed: 12/12/2022] Open
Abstract
In multiple sclerosis (MS), demyelinated CNS lesions fail to sufficiently remyelinate, despite the presence of oligodendrocyte precursor cells (OPCs) capable of differentiating into mature oligodendrocytes. MS lesions contain damaged myelin debris that can inhibit OPC maturation and hinder repair. rHIgM22 is an experimental human recombinant IgM antibody that promotes remyelination in animal models and is being examined in patients with MS. rHIgM22 binds to CNS myelin and partially rescues OPC process outgrowth on myelin. Since rHIgM22 does not affect OPC process outgrowth in vitro on permissive substrate, we examined the possibility that it acts by enhancing phagocytic clearance of myelin debris by microglia. In this study, we tested if rHIgM22 binding could tag myelin for microglial phagocytosis. A mouse microglial cell line and primary rat microglia were treated with myelin and rHIgM22 and assayed for myelin phagocytosis. We found that: 1) rHIgM22 stimulates myelin phagocytosis in a dose-dependent manner; 2) rHIgM22-mediated myelin phagocytosis requires actin polymerization; and 3) rHIgM22-stimulation of myelin phagocytosis requires activity of rHIgM22 Fc domain and activation of Complement Receptor 3. Since myelin inhibits OPC differentiation, stimulation of phagocytic clearance of damaged myelin may be an important means by which rHIgM22 promotes remyelination.
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19
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Mizee MR, Poel MVD, Huitinga I. Purification of cells from fresh human brain tissue: primary human glial cells. HANDBOOK OF CLINICAL NEUROLOGY 2018; 150:273-283. [PMID: 29496146 DOI: 10.1016/b978-0-444-63639-3.00019-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In order to translate the findings obtained from postmortem brain tissue samples to functional biologic mechanisms of central nervous system disease, it will be necessary to understand how these findings affect the different cell populations in the brain. The acute isolation and analysis of pure glial cell populations are common practice in animal models for neurologic diseases, but are not yet regularly applied to human postmortem brain material. The development of novel cell isolation techniques and methods for transcriptomic and proteomic analysis have made it possible to isolate and phenotype primary human cell populations from the central nervous system. The psychiatric program of the Netherlands Brain Bank has considerable experience with the purification of glial cells. This chapter will review the rapid isolation and phenotyping procedures for two major glia cell populations in the human brain, microglia and astrocytes, and will also discuss the potential for biobanking these cells, as well as the possible alternatives to cell isolations. The acute isolation of glial cells without culture-based adherence steps allows the analysis of glial alterations that underlie, or are the result of, disease neuropathology of the donor.
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Affiliation(s)
- Mark Ronald Mizee
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Amsterdam, The Netherlands; Psychiatric Program, Netherlands Brain Bank, Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
| | - Marlijn van der Poel
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Amsterdam, The Netherlands
| | - Inge Huitinga
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Amsterdam, The Netherlands; Psychiatric Program, Netherlands Brain Bank, Netherlands Institute for Neuroscience, Amsterdam, The Netherlands.
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20
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Hendrickx DAE, van Scheppingen J, van der Poel M, Bossers K, Schuurman KG, van Eden CG, Hol EM, Hamann J, Huitinga I. Gene Expression Profiling of Multiple Sclerosis Pathology Identifies Early Patterns of Demyelination Surrounding Chronic Active Lesions. Front Immunol 2017; 8:1810. [PMID: 29312322 PMCID: PMC5742619 DOI: 10.3389/fimmu.2017.01810] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 12/01/2017] [Indexed: 01/22/2023] Open
Abstract
In multiple sclerosis (MS), activated microglia and infiltrating macrophages phagocytose myelin focally in (chronic) active lesions. These demyelinating sites expand in time, but at some point turn inactive into a sclerotic scar. To identify molecular mechanisms underlying lesion activity and halt, we analyzed genome-wide gene expression in rim and peri-lesional regions of chronic active and inactive MS lesions, as well as in control tissue. Gene clustering revealed patterns of gene expression specifically associated with MS and with the presumed, subsequent stages of lesion development. Next to genes involved in immune functions, we found regulation of novel genes in and around the rim of chronic active lesions, such as NPY, KANK4, NCAN, TKTL1, and ANO4. Of note, the presence of many foamy macrophages in active rims was accompanied by a congruent upregulation of genes related to lipid binding, such as MSR1, CD68, CXCL16, and OLR1, and lipid uptake, such as CHIT1, GPNMB, and CCL18. Except CCL18, these genes were already upregulated in regions around active MS lesions, showing that such lesions are indeed expanding. In vitro downregulation of the scavenger receptors MSR1 and CXCL16 reduced myelin uptake. In conclusion, this study provides the gene expression profile of different aspects of MS pathology and indicates that early demyelination, mediated by scavenger receptors, is already present in regions around active MS lesions. Genes involved in early demyelination events in regions surrounding chronic active MS lesions might be promising therapeutic targets to stop lesion expansion.
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Affiliation(s)
- Debbie A E Hendrickx
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Jackelien van Scheppingen
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Marlijn van der Poel
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Koen Bossers
- Neurodegeneration Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Karianne G Schuurman
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Corbert G van Eden
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
| | - Elly M Hol
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands.,Department of Translational Neuroscience, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, Netherlands.,Swammerdam Institute for Life Sciences, Center for Neuroscience, University of Amsterdam, Amsterdam, Netherlands
| | - Jörg Hamann
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands.,Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Inge Huitinga
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, An Institute of the Royal Netherlands Academy of Arts and Sciences, Amsterdam, Netherlands
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21
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TLR4 Deficiency Impairs Oligodendrocyte Formation in the Injured Spinal Cord. J Neurosci 2017; 36:6352-64. [PMID: 27277810 DOI: 10.1523/jneurosci.0353-16.2016] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 05/05/2016] [Indexed: 12/12/2022] Open
Abstract
UNLABELLED Acute oligodendrocyte (OL) death after traumatic spinal cord injury (SCI) is followed by robust neuron-glial antigen 2 (NG2)-positive OL progenitor proliferation and differentiation into new OLs. Inflammatory mediators are prevalent during both phases and can influence the fate of NG2 cells and OLs. Specifically, toll-like receptor (TLR) 4 signaling induces OL genesis in the naive spinal cord, and lack of TLR4 signaling impairs white matter sparing and functional recovery after SCI. Therefore, we hypothesized that TLR4 signaling may regulate oligodendrogenesis after SCI. C3H/HeJ (TLR4-deficient) and control (C3H/HeOuJ) mice received a moderate midthoracic spinal contusion. TLR4-deficient mice showed worse functional recovery and reduced OL numbers compared with controls at 24 h after injury through chronic time points. Acute OL loss was accompanied by reduced ferritin expression, which is regulated by TLR4 and needed for effective iron storage. TLR4-deficient injured spinal cords also displayed features consistent with reduced OL genesis, including reduced NG2 expression, fewer BrdU-positive OLs, altered BMP4 signaling and inhibitor of differentiation 4 (ID4) expression, and delayed myelin phagocytosis. Expression of several factors, including IGF-1, FGF2, IL-1β, and PDGF-A, was altered in TLR4-deficient injured spinal cords compared with wild types. Together, these data show that TLR4 signaling after SCI is important for OL lineage cell sparing and replacement, as well as in regulating cytokine and growth factor expression. These results highlight new roles for TLR4 in endogenous SCI repair and emphasize that altering the function of a single immune-related receptor can dramatically change the reparative responses of multiple cellular constituents in the injured CNS milieu. SIGNIFICANCE STATEMENT Myelinating cells of the CNS [oligodendrocytes (OLs)] are killed for several weeks after traumatic spinal cord injury (SCI), but they are replaced by resident progenitor cells. How the concurrent inflammatory signaling affects this endogenous reparative response is unclear. Here, we provide evidence that immune receptor toll-like receptor 4 (TLR4) supports OL lineage cell sparing, long-term OL and OL progenitor replacement, and chronic functional recovery. We show that TLR4 signaling is essential for acute iron storage, regulating cytokine and growth factor expression, and efficient myelin debris clearance, all of which influence OL replacement. Importantly, the current study reveals that a single immune receptor is essential for repair responses after SCI, and the potential mechanisms of this beneficial effect likely change over time after injury.
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22
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Old Maids: Aging and Its Impact on Microglia Function. Int J Mol Sci 2017; 18:ijms18040769. [PMID: 28379162 PMCID: PMC5412353 DOI: 10.3390/ijms18040769] [Citation(s) in RCA: 141] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 03/27/2017] [Accepted: 03/28/2017] [Indexed: 12/20/2022] Open
Abstract
Microglia are highly active and vigilant housekeepers of the central nervous system that function to promote neuronal growth and activity. With advanced age, however, dysregulated inflammatory signaling and defects in phagocytosis impede their ability to perform the most essential of homeostatic functions, including immune surveillance and debris clearance. Microglial activation is one of the hallmarks of the aging brain and coincides with age-related neurodegeneration and cognitive decline. Age-associated microglial dysfunction leads to cellular senescence and can profoundly alter the response to sterile injuries and immune diseases, often resulting in maladaptive responses, chronic inflammation, and worsened outcomes after injury. Our knowledge of microglia aging and the factors that regulate age-related microglial dysfunction remain limited, as the majority of pre-clinical studies are performed in young animals, and human brain samples are difficult to obtain quickly post-mortem or in large numbers. This review outlines the impact of normal aging on microglial function, highlights the potential mechanisms underlying age-related changes in microglia, and discusses how aging can shape the recovery process following injury.
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23
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Church JS, Milich LM, Lerch JK, Popovich PG, McTigue DM. E6020, a synthetic TLR4 agonist, accelerates myelin debris clearance, Schwann cell infiltration, and remyelination in the rat spinal cord. Glia 2017; 65:883-899. [PMID: 28251686 DOI: 10.1002/glia.23132] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Revised: 02/02/2017] [Accepted: 02/03/2017] [Indexed: 12/26/2022]
Abstract
Oligodendrocyte progenitor cells (OPCs) are present throughout the adult brain and spinal cord and can replace oligodendrocytes lost to injury, aging, or disease. Their differentiation, however, is inhibited by myelin debris, making clearance of this debris an important step for cellular repair following demyelination. In models of peripheral nerve injury, TLR4 activation by lipopolysaccharide (LPS) promotes macrophage phagocytosis of debris. Here we tested whether the novel synthetic TLR4 agonist E6020, a Lipid A mimetic, promotes myelin debris clearance and remyelination in spinal cord white matter following lysolecithin-induced demyelination. In vitro, E6020 induced TLR4-dependent cytokine expression (TNFα, IL1β, IL-6) and NF-κB signaling, albeit at ∼10-fold reduced potency compared to LPS. Microinjection of E6020 into the intact rat spinal cord gray/white matter border induced macrophage activation, OPC proliferation, and robust oligodendrogenesis, similar to what we described previously using an intraspinal LPS microinjection model. Finally, a single co-injection of E6020 with lysolecithin into spinal cord white matter increased axon sparing, accelerated myelin debris clearance, enhanced Schwann cell infiltration into demyelinated lesions, and increased the number of remyelinated axons. In vitro assays confirmed that direct stimulation of macrophages by E6020 stimulates myelin phagocytosis. These data implicate TLR4 signaling in promoting repair after CNS demyelination, likely by stimulating phagocytic activity of macrophages, sparing axons, recruiting myelinating cells, and promoting remyelination. This work furthers our understanding of immune-myelin interactions and identifies a novel synthetic TLR4 agonist as a potential therapeutic avenue for white matter demyelinating conditions such as spinal cord injury and multiple sclerosis.
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Affiliation(s)
- Jamie S Church
- Neuroscience Graduate Program, The Ohio State University, Columbus, Ohio, USA.,Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA
| | - Lindsay M Milich
- Department of Neuroscience, The Ohio State University, Columbus, Ohio, USA
| | - Jessica K Lerch
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA.,Department of Neuroscience, The Ohio State University, Columbus, Ohio, USA
| | - Phillip G Popovich
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA.,Department of Neuroscience, The Ohio State University, Columbus, Ohio, USA
| | - Dana M McTigue
- Center for Brain and Spinal Cord Repair, The Ohio State University, Columbus, Ohio, USA.,Department of Neuroscience, The Ohio State University, Columbus, Ohio, USA
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Mizee MR, Miedema SSM, van der Poel M, Adelia, Schuurman KG, van Strien ME, Melief J, Smolders J, Hendrickx DA, Heutinck KM, Hamann J, Huitinga I. Isolation of primary microglia from the human post-mortem brain: effects of ante- and post-mortem variables. Acta Neuropathol Commun 2017; 5:16. [PMID: 28212663 PMCID: PMC5316206 DOI: 10.1186/s40478-017-0418-8] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2017] [Accepted: 02/05/2017] [Indexed: 03/17/2023] Open
Abstract
Microglia are key players in the central nervous system in health and disease. Much pioneering research on microglia function has been carried out in vivo with the use of genetic animal models. However, to fully understand the role of microglia in neurological and psychiatric disorders, it is crucial to study primary human microglia from brain donors. We have developed a rapid procedure for the isolation of pure human microglia from autopsy tissue using density gradient centrifugation followed by CD11b-specific cell selection. The protocol can be completed in 4 h, with an average yield of 450,000 and 145,000 viable cells per gram of white and grey matter tissue respectively. This method allows for the immediate phenotyping of microglia in relation to brain donor clinical variables, and shows the microglia population to be distinguishable from autologous choroid plexus macrophages. This protocol has been applied to samples from over 100 brain donors from the Netherlands Brain Bank, providing a robust dataset to analyze the effects of age, post-mortem delay, brain acidity, and neurological diagnosis on microglia yield and phenotype. Our data show that cerebrospinal fluid pH is positively correlated to microglial cell yield, but donor age and post-mortem delay do not negatively affect viable microglia yield. Analysis of CD45 and CD11b expression showed that changes in microglia phenotype can be attributed to a neurological diagnosis, and are not influenced by variation in ante- and post-mortem parameters. Cryogenic storage of primary microglia was shown to be possible, albeit with variable levels of recovery and effects on phenotype and RNA quality. Microglial gene expression substantially changed due to culture, including the loss of the microglia-specific markers, showing the importance of immediate microglia phenotyping. We conclude that primary microglia can be isolated effectively and rapidly from human post-mortem brain tissue, allowing for the study of the microglial population in light of the neuropathological status of the donor.
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25
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Lenzo JC, O'Brien-Simpson NM, Cecil J, Holden JA, Reynolds EC. Determination of Active Phagocytosis of Unopsonized Porphyromonas gingivalis by Macrophages and Neutrophils Using the pH-Sensitive Fluorescent Dye pHrodo. Infect Immun 2016; 84:1753-1760. [PMID: 27021243 PMCID: PMC4907136 DOI: 10.1128/iai.01482-15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 03/23/2016] [Indexed: 01/15/2023] Open
Abstract
Phagocytosis of pathogens is an important component of the innate immune system that is responsible for the removal and degradation of bacteria as well as their presentation via the major histocompatibility complexes to the adaptive immune system. The periodontal pathogen Porphyromonas gingivalis exhibits strain heterogeneity, which may affect a phagocyte's ability to recognize and phagocytose the bacterium. In addition, P. gingivalis is reported to avoid phagocytosis by antibody and complement degradation and by invading phagocytic cells. Previous studies examining phagocytosis have been confounded by both the techniques employed and the potential of the bacteria to invade the cells. In this study, we used a novel, pH-sensitive dye, pHrodo, to label live P. gingivalis strains and examine unopsonized phagocytosis by murine macrophages and neutrophils and human monocytic cells. All host cells examined were able to recognize and phagocytose unopsonized P. gingivalis strains. Macrophages had a preference to phagocytose P. gingivalis strain ATCC 33277 over other strains and clinical isolates in the study, whereas neutrophils favored P. gingivalis W50, ATCC 33277, and one clinical isolate over the other strains. This study revealed that all P. gingivalis strains were capable of being phagocytosed without prior opsonization with antibody or complement.
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Affiliation(s)
- Jason C Lenzo
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Neil M O'Brien-Simpson
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Jessica Cecil
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - James A Holden
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, Australia
| | - Eric C Reynolds
- Oral Health Cooperative Research Centre, Melbourne Dental School, Bio21 Institute, The University of Melbourne, Melbourne, Victoria, Australia
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26
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Systemic ocular antigen immunization leads only to a minor secondary immune response. J Neuroimmunol 2016; 293:114-122. [DOI: 10.1016/j.jneuroim.2016.02.017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Revised: 02/24/2016] [Accepted: 02/26/2016] [Indexed: 11/13/2022]
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27
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Rachmawati D, Peferoen LA, Vogel DY, Alsalem IW, Amor S, Bontkes HJ, von Blomberg BME, Scheper RJ, van Hoogstraten IM. Metal ions potentiate microglia responsiveness to endotoxin. J Neuroimmunol 2016; 291:89-95. [DOI: 10.1016/j.jneuroim.2015.12.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 12/14/2015] [Accepted: 12/28/2015] [Indexed: 12/14/2022]
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28
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Volden TA, Reyelts CD, Hoke TA, Arikkath J, Bonasera SJ. Validation of Flow Cytometry and Magnetic Bead-Based Methods to Enrich CNS Single Cell Suspensions for Quiescent Microglia. J Neuroimmune Pharmacol 2015; 10:655-65. [PMID: 26260923 DOI: 10.1007/s11481-015-9628-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Accepted: 07/30/2015] [Indexed: 11/29/2022]
Abstract
Microglia are resident mononuclear phagocytes within the CNS parenchyma that intimately interact with neurons and astrocytes to remodel synapses and extracellular matrix. We briefly review studies elucidating the molecular pathways that underlie microglial surveillance, activation, chemotaxis, and phagocytosis; we additionally place these studies in a clinical context. We describe and validate an inexpensive and simple approach to obtain enriched single cell suspensions of quiescent parenchymal and perivascular microglia from the mouse cerebellum and hypothalamus. Following preparation of regional CNS single cell suspensions, we remove myelin debris, and then perform two serial enrichment steps for cells expressing surface CD11b. Myelin depletion and CD11b enrichment are both accomplished using antigen-specific magnetic beads in an automated cell separation system. Flow cytometry of the resultant suspensions shows a significant enrichment for CD11b(+)/CD45(+) cells (perivascular microglia) and CD11b(+)/CD45(-) cells (parenchymal microglia) compared to starting suspensions. Of note, cells from these enriched suspensions minimally express Aif1 (aka Iba1), suggesting that the enrichment process does not evoke significant microglial activation. However, these cells readily respond to a functional challenge (LPS) with significant changes in the expression of molecules specifically associated with microglia. We conclude that methods employing a combination of magnetic-bead based sorting and flow cytometry produce suspensions highly enriched for microglia that are appropriate for a variety of molecular and cellular assays.
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Affiliation(s)
- T A Volden
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - C D Reyelts
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - T A Hoke
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - J Arikkath
- Developmental Neuroscience, Munroe-Meyer Institute for Genetics and Rehabilitation, University of Nebraska Medical Center, Omaha, NE, 68198, USA
| | - S J Bonasera
- Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, 68198, USA. .,University of Nebraska Medical Center, 3028 Durham Research Center II, Omaha, NE, 68198-5039, USA.
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Serum proteomics in multiple sclerosis disease progression. J Proteomics 2015; 118:2-11. [PMID: 25753122 DOI: 10.1016/j.jprot.2015.02.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 01/30/2015] [Accepted: 02/15/2015] [Indexed: 11/20/2022]
Abstract
UNLABELLED Multiple sclerosis (MS) is associated with chronic degeneration of the central nervous system and may cause permanent neurological problems and considerable disability. While its causes remain unclear, its extensive phenotypic variability makes its prognosis and treatment difficult. The identification of serum proteomic biomarkers of MS progression could further our understanding of the molecular mechanisms related to MS disease processes. In the current study, we used isobaric tagging for relative and absolute protein quantification (iTRAQ) methodology and advanced multivariate statistical analysis to quantify and identify potential serum biomarker proteins of MS progression. We identified a panel of 11 proteins and combined them into a classifier that best classified samples into the two disease groups. The estimated area under the receiver operating curve of this classifier was 0.88 (p-value=0.017), with 86% sensitivity and specificity. The identified proteins encompassed processes related to inflammation, opsonization, and complement activation. Results from this study are in particular valuable to design a targeted Multiple Reaction Monitoring mass spectrometry based (MRM-MS) assay to conduct an external validation in an independent and larger cohort of patients. Validated biomarkers may result in the development of a minimally-invasive tool to monitor MS progression and complement current clinical practices. BIOLOGICAL SIGNIFICANCE A hallmark of multiple sclerosis is the unpredictable disease course (progression). There are currently no clinically useful biomarkers of MS disease progression; most work has focused on the analysis of CSF, which requires an invasive procedure. Here, we explore the potential of proteomics to identify panels of serum biomarkers of disease progression in MS. By comparing the protein signatures of two challenging to obtain, but well-defined, MS phenotypic groups at the extremes of progression (benign and aggressive cases of MS), we identified proteins that encompass processes related to inflammation, opsonization, and complement activation. Findings require validation, but are an important step on the pathway to clinically useful biomarker discovery. This article is part of a Special Issue entitled: Protein dynamics in health and disease. Guest Editors: Pierre Thibault and Anne-Claude Gingras.
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