1
|
Saez-Calveras N, Brewster AL, Stuve O. The validity of animal models to explore the pathogenic role of the complement system in multiple sclerosis: A review. Front Mol Neurosci 2022; 15:1017484. [PMID: 36311030 PMCID: PMC9606595 DOI: 10.3389/fnmol.2022.1017484] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 09/26/2022] [Indexed: 11/26/2022] Open
Abstract
Animal models of multiple sclerosis (MS) have been extensively used to characterize the disease mechanisms in MS, as well as to identify potential pharmacologic targets for this condition. In recent years, the immune complement system has gained increased attention as an important effector in the pathogenesis of MS. Evidence from histological, serum, and CSF studies of patients supports an involvement of complement in both relapsing-remitting and progressive MS. In this review, we discuss the history and advances made on the use of MS animal models to profile the effects of the complement system in this condition. The first studies that explored the complement system in the context of MS used cobra venom factor (CVF) as a complement depleting agent in experimental autoimmune encephalomyelitis (EAE) Lewis rats. Since then, multiple mice and rat models of MS have revealed a role of C3 and the alternative complement cascade in the opsonization and phagocytosis of myelin by microglia and myeloid cells. Studies using viral vectors, genetic knockouts and pharmacologic complement inhibitors have also shown an effect of complement in synaptic loss. Antibody-mediated EAE models have revealed an involvement of the C1 complex and the classical complement as an effector of the humoral response in this disease. C1q itself may also be involved in modulating microglia activation and oligodendrocyte differentiation in these animals. In addition, animal and in vitro models have revealed that multiple complement factors may act as modulators of both the innate and adaptive immune responses. Finally, evidence gathered from mice models suggests that the membrane attack complex (MAC) may even exert protective roles in the chronic stages of EAE. Overall, this review summarizes the importance of MS animal models to better characterize the role of the complement system and guide future therapeutic approaches in this condition.
Collapse
Affiliation(s)
- Nil Saez-Calveras
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Neurology Section, Parkland Hospital, Dallas, TX, United States
| | - Amy L. Brewster
- Department of Biological Sciences, Southern Methodist University, Dallas, TX, United States
| | - Olaf Stuve
- Department of Neurology, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Neurology Section, VA North Texas Health Care System, Dallas, TX, United States
- Peter O’Donnell Brain Institute, University of Texas Southwestern Medical Center, Dallas, TX, United States
- *Correspondence: Olaf Stuve,
| |
Collapse
|
2
|
Mutoh T, Niimi Y, Sakai S, Watanabe H, Ueda A, Shima S, Igarashi Y. Species-specific accumulation of ceramides in cerebrospinal fluid from encephalomyeloradiculoneurpathy patients associated with peripheral complement activation: A pilot study. Biochim Biophys Acta Mol Cell Biol Lipids 2022; 1867:159092. [PMID: 34942380 DOI: 10.1016/j.bbalip.2021.159092] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/30/2021] [Accepted: 12/08/2021] [Indexed: 11/24/2022]
Abstract
Glycolipids are now known to be rapidly converted to mediators for inflammatory reactions or to signaling molecules that control inflammatory events in the nervous system. The present study aimed to explore whether disturbed glycolipids metabolism in the nervous system is present in patients with a neuroinflammatory disorder, encephalo-myelo-radiculo-neuropathy (EMRN), because most EMRN patients have been reported to exhibit autoantibodies against neutral glycolipids. Although molecular pathogenesis of this disorder remains unknown, we tried to search the immunochemical abnormalities in this disorder. ELISA for activated peripheral C5 complement and mass spectrometry analysis of cerebrospinal fluid clearly disclosed a significant upregulation of active C5 complement, C5a levels in sera as well as a significant accumulation of species-specific ceramides but not sphingomyelin in cerebrospinal fluid from EMRN patients. Furthermore, we confirmed the occurrence of anti-neutral glycolipids antibodies in all EMRN patients. Thus, the present study might indicate the pathophysiology of this disorder is the dysregulation of glycolipids metabolism and abnormal production of autoantibodies against neutral glycolipids resulting in the abnormal complement activation, although molecular basis for these sphingolipids dysregulation and the occurrence of autoantibodies against glycolipids remains to be elucidated at present. The present study implicates a new therapeutic strategy employing anti-ceramide and/or anti-complement therapy for this disorder.
Collapse
Affiliation(s)
- Tatsuro Mutoh
- Department of Neurology and Neuroscience, Fujita Health University Hospital, Aichi, Japan.
| | - Yoshiki Niimi
- Department of Neurology and Neuroscience, Fujita Health University Hospital, Aichi, Japan
| | - Shota Sakai
- Faculty of Pharmacy, Laboratory of Biomembrane and Biofunctional Chemistry, Graduate School of Advanced Life Science and Frontier Research Center for Advanced Material and Life Science, Hokkaido University, Hokkaido, Japan
| | - Hirohisa Watanabe
- Department of Neurology and Neuroscience, Fujita Health University Hospital, Aichi, Japan
| | - Akihiro Ueda
- Department of Neurology and Neuroscience, Fujita Health University Hospital, Aichi, Japan
| | - Sayuri Shima
- Department of Neurology and Neuroscience, Fujita Health University Hospital, Aichi, Japan
| | - Yasuyuki Igarashi
- Faculty of Pharmacy, Laboratory of Biomembrane and Biofunctional Chemistry, Graduate School of Advanced Life Science and Frontier Research Center for Advanced Material and Life Science, Hokkaido University, Hokkaido, Japan
| |
Collapse
|
3
|
Ziabska K, Ziemka-Nalecz M, Pawelec P, Sypecka J, Zalewska T. Aberrant Complement System Activation in Neurological Disorders. Int J Mol Sci 2021; 22:4675. [PMID: 33925147 PMCID: PMC8125564 DOI: 10.3390/ijms22094675] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Revised: 04/22/2021] [Accepted: 04/26/2021] [Indexed: 12/13/2022] Open
Abstract
The complement system is an assembly of proteins that collectively participate in the functions of the healthy and diseased brain. The complement system plays an important role in the maintenance of uninjured (healthy) brain homeostasis, contributing to the clearance of invading pathogens and apoptotic cells, and limiting the inflammatory immune response. However, overactivation or underregulation of the entire complement cascade within the brain may lead to neuronal damage and disturbances in brain function. During the last decade, there has been a growing interest in the role that this cascading pathway plays in the neuropathology of a diverse array of brain disorders (e.g., acute neurotraumatic insult, chronic neurodegenerative diseases, and psychiatric disturbances) in which interruption of neuronal homeostasis triggers complement activation. Dysfunction of the complement promotes a disease-specific response that may have either beneficial or detrimental effects. Despite recent advances, the explicit link between complement component regulation and brain disorders remains unclear. Therefore, a comprehensible understanding of such relationships at different stages of diseases could provide new insight into potential therapeutic targets to ameliorate or slow progression of currently intractable disorders in the nervous system. Hence, the aim of this review is to provide a summary of the literature on the emerging role of the complement system in certain brain disorders.
Collapse
Affiliation(s)
| | | | | | | | - Teresa Zalewska
- Mossakowski Medical Research Centre, NeuroRepair Department, Polish Academy of Sciences, 5 Pawinskiego Street, 02-106 Warsaw, Poland; (K.Z.); (M.Z.-N.); (P.P.); (J.S.)
| |
Collapse
|
4
|
Abstract
Multiple sclerosis (MS) is a complex inflammatory disease of the central nervous system (CNS) with an unknown etiology. Thereby, MS is not a uniform disease but rather represents a spectrum of disorders, where each aspect needs to be modeled with specific requirements-for a systematic overview see our previous issue of this review (Kurschus, Wortge, & Waisman, 2011). However, there is broad consensus about the critical involvement of the immune system in the disease pathogenesis. To better understand how the immune system contributes to CNS autoimmunity, the model of experimental autoimmune encephalomyelitis (EAE) was developed. EAE can be induced in susceptible animals in many different ways, with the most popular protocol involving the activation of self-reactive T cells by a peptide based on the myelin oligodendrocyte glycoprotein sequence. In the last 10 years this model has led to major advances in our understanding of the immune system, especially the nature of IL-17-producing T cells (Th17 cells), host-microbiome interactions, the gut-brain axis and how the immune system can cause damage in different regions of the brain and the spinal cord. This update summarizes some of the main achievements in the field in the last 10 years.
Collapse
Affiliation(s)
- Tommy Regen
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany.
| | - Ari Waisman
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| |
Collapse
|
5
|
Asavapanumas N, Tradtrantip L, Verkman AS. Targeting the complement system in neuromyelitis optica spectrum disorder. Expert Opin Biol Ther 2021; 21:1073-1086. [PMID: 33513036 DOI: 10.1080/14712598.2021.1884223] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Neuromyelitis optica spectrum disorder (NMOSD) is characterized by central nervous system inflammation and demyelination. In AQP4-IgG seropositive NMOSD, circulating immunoglobulin G (IgG) autoantibodies against astrocyte water channel aquaporin-4 (AQP4) cause tissue injury. Compelling evidence supports a pathogenic role for complement activation following AQP4-IgG binding to AQP4. Clinical studies supported the approval of eculizumab, an inhibitor of C5 cleavage, in AQP4-IgG seropositive NMOSD. AREAS COVERED This review covers in vitro, animal models, and human evidence for complement-dependent and complement-independent tissue injury in AQP4-IgG seropositive NMOSD. Complement targets are discussed, including complement proteins, regulators and anaphylatoxin receptors, and corresponding drug candidates. EXPERT OPINION Though preclinical data support a central pathogenic role of complement activation in AQP4-IgG seropositive NMOSD, they do not resolve the relative contributions of complement-dependent vs. complement-independent disease mechanisms such as antibody-dependent cellular cytotoxicity, T cell effector mechanisms, and direct AQP4-IgG-induced cellular injury. The best evidence that complement-dependent mechanisms predominate in AQP4-IgG seropositive NMOSD comes from eculizumab clinical data. Various drug candidates targeting distinct complement effector mechanisms may offer improved safety and efficacy. However, notwithstanding the demonstrated efficacy of complement inhibition in AQP4-IgG seropositive NMOSD, the ultimate niche for complement inhibition is not clear given multiple drug options with alternative mechanisms of action.Abbreviations: AAV2, Adeno-associated virus 2; ADCC, antibody-dependent cellular cytotoxicity; ANCA, antineutrophilic cytoplasmic autoantibody; AQP4, aquaporin-4; AQP4-IgG, AQP4-immunoglobulin G; C1-INH, C1-esterase inhibitor; C3aR, C3a receptor; C4BP, C4 binding protein; C5aR, C5a receptor; CDC, complement-dependent cytotoxicity; CFHR1, complement factor H related 1; CNS, central nervous system; EAE, experimental autoimmune encephalomyelitis; EndoS, endoglycosidase S; FHL-1, factor-H-like protein 1; GFAP, glial fibrillary acidic protein; Iba-1, ionized calcium-binding adaptor protein-1; IgG, immunoglobulin G; IVIG, intravenous human immunoglobulin G; MAC, membrane attack complex; MBL, maltose-binding lectin; MBP, myelin basic protein; MOG, myelin oligodendrocyte glycoprotein; NK cell, natural killer cell; NMOSD, neuromyelitis optica spectrum disorder; OAP, orthogonal arrays of particles; PNH, paroxysmal nocturnal hemoglobinuria.
Collapse
Affiliation(s)
- Nithi Asavapanumas
- Chakri Naruebodindra Medical Institute, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, Thailand
| | - Lukmanee Tradtrantip
- Departments of Medicine and Physiology, University of California, San Francisco, CA, USA
| | - Alan S Verkman
- Departments of Medicine and Physiology, University of California, San Francisco, CA, USA
| |
Collapse
|
6
|
Morgan BP, Gommerman JL, Ramaglia V. An "Outside-In" and "Inside-Out" Consideration of Complement in the Multiple Sclerosis Brain: Lessons From Development and Neurodegenerative Diseases. Front Cell Neurosci 2021; 14:600656. [PMID: 33488361 PMCID: PMC7817777 DOI: 10.3389/fncel.2020.600656] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 11/24/2020] [Indexed: 12/14/2022] Open
Abstract
The last 15 years have seen an explosion of new findings on the role of complement, a major arm of the immune system, in the central nervous system (CNS) compartment including contributions to cell migration, elimination of synapse during development, aberrant synapse pruning in neurologic disorders, damage to nerve cells in autoimmune diseases, and traumatic injury. Activation of the complement system in multiple sclerosis (MS) is typically thought to occur as part of a primary (auto)immune response from the periphery (the outside) against CNS antigens (the inside). However, evidence of local complement production from CNS-resident cells, intracellular complement functions, and the more recently discovered role of early complement components in shaping synaptic circuits in the absence of inflammation opens up the possibility that complement-related sequelae may start and finish within the brain itself. In this review, the complement system will be introduced, followed by evidence that implicates complement in shaping the developing, adult, and normal aging CNS as well as its contribution to pathology in neurodegenerative conditions. Discussion of data supporting "outside-in" vs. "inside-out" roles of complement in MS will be presented, concluded by thoughts on potential approaches to therapies targeting specific elements of the complement system.
Collapse
Affiliation(s)
- B. Paul Morgan
- UK Dementia Research Institute at Cardiff, Cardiff University, Cardiff, United Kingdom
| | | | - Valeria Ramaglia
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
7
|
Dalakas MC, Alexopoulos H, Spaeth PJ. Complement in neurological disorders and emerging complement-targeted therapeutics. Nat Rev Neurol 2020; 16:601-617. [PMID: 33005040 PMCID: PMC7528717 DOI: 10.1038/s41582-020-0400-0] [Citation(s) in RCA: 222] [Impact Index Per Article: 44.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/07/2020] [Indexed: 12/30/2022]
Abstract
The complement system consists of a network of plasma and membrane proteins that modulate tissue homeostasis and contribute to immune surveillance by interacting with the innate and adaptive immune systems. Dysregulation, impairment or inadvertent activation of complement components contribute to the pathogenesis of some autoimmune neurological disorders and could even contribute to neurodegenerative diseases. In this Review, we summarize current knowledge about the main functions of the complement pathways and the involvement of complement in neurological disorders. We describe the complex network of complement proteins that target muscle, the neuromuscular junction, peripheral nerves, the spinal cord or the brain and discuss the autoimmune mechanisms of complement-mediated myopathies, myasthenia, peripheral neuropathies, neuromyelitis and other CNS disorders. We also consider the emerging role of complement in some neurodegenerative diseases, such as Alzheimer disease, amyotrophic lateral sclerosis and even schizophrenia. Finally, we provide an overview of the latest complement-targeted immunotherapies including monoclonal antibodies, fusion proteins and peptidomimetics that have been approved, that are undergoing phase I–III clinical trials or that show promise for the treatment of neurological conditions that respond poorly to existing immunotherapies. In this Review, Dalakas et al. discuss the complement system, the role it plays in autoimmune neurological disease and neurodegenerative disease, and provide an overview of the latest therapeutics that target complement and that can be used for or have potential in neurological disorders. Complement has an important physiological role in host immune defences and tissue remodelling. The physiological role of complement extends to the regulation of synaptic development. Complement has a key pathophysiological role in autoimmune neurological diseases and mediates the actions of pathogenic autoantibodies, such as acetylcholine receptor antibodies and aquaporin 4 antibodies. For some autoimmune neurological diseases, such as myasthenia gravis and neuromyelitis optica spectrum disorders, approved complement-targeted treatments are now available. Complement also seems to be of pathogenic relevance in neurodegenerative diseases such as Alzheimer disease, in which innate immune-driven inflammation is receiving increasing attention. The field of complement-targeted therapeutics is rapidly expanding, with several FDA-approved agents and others currently in phase II and phase III clinical trials.
Collapse
Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA. .,Neuroimmunology Unit, Department of Pathophysiology, Faculty of Medicine, National and Kapodistrian University of Athens, Athens, Greece.
| | - Harry Alexopoulos
- Neuroimmunology Unit, Department of Pathophysiology, Faculty of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Peter J Spaeth
- Institute of Pharmacology, University of Bern, Bern, Switzerland
| |
Collapse
|
8
|
Üçal M, Haindl MT, Adzemovic MZ, Strasser J, Theisl L, Zeitelhofer M, Kraitsy K, Ropele S, Schäfer U, Fazekas F, Hochmeister S. Widespread cortical demyelination of both hemispheres can be induced by injection of pro-inflammatory cytokines via an implanted catheter in the cortex of MOG-immunized rats. Exp Neurol 2017; 294:32-44. [DOI: 10.1016/j.expneurol.2017.04.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Revised: 04/13/2017] [Accepted: 04/26/2017] [Indexed: 01/22/2023]
|
9
|
A review of human diseases caused or exacerbated by aberrant complement activation. Neurobiol Aging 2017; 52:12-22. [DOI: 10.1016/j.neurobiolaging.2016.12.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 11/15/2016] [Accepted: 12/18/2016] [Indexed: 12/14/2022]
|
10
|
Watkins LM, Neal JW, Loveless S, Michailidou I, Ramaglia V, Rees MI, Reynolds R, Robertson NP, Morgan BP, Howell OW. Complement is activated in progressive multiple sclerosis cortical grey matter lesions. J Neuroinflammation 2016; 13:161. [PMID: 27333900 PMCID: PMC4918026 DOI: 10.1186/s12974-016-0611-x] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 06/03/2016] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND The symptoms of multiple sclerosis (MS) are caused by damage to myelin and nerve cells in the brain and spinal cord. Inflammation is tightly linked with neurodegeneration, and it is the accumulation of neurodegeneration that underlies increasing neurological disability in progressive MS. Determining pathological mechanisms at play in MS grey matter is therefore a key to our understanding of disease progression. METHODS We analysed complement expression and activation by immunocytochemistry and in situ hybridisation in frozen or formalin-fixed paraffin-embedded post-mortem tissue blocks from 22 progressive MS cases and made comparisons to inflammatory central nervous system disease and non-neurological disease controls. RESULTS Expression of the transcript for C1qA was noted in neurons and the activation fragment and opsonin C3b-labelled neurons and glia in the MS cortical and deep grey matter. The density of immunostained cells positive for the classical complement pathway protein C1q and the alternative complement pathway activation fragment Bb was significantly increased in cortical grey matter lesions in comparison to control grey matter. The number of cells immunostained for the membrane attack complex was elevated in cortical lesions, indicating complement activation to completion. The numbers of classical (C1-inhibitor) and alternative (factor H) pathway regulator-positive cells were unchanged between MS and controls, whilst complement anaphylatoxin receptor-bearing microglia in the MS cortex were found closely apposed to cortical neurons. Complement immunopositive neurons displayed an altered nuclear morphology, indicative of cell stress/damage, supporting our finding of significant neurodegeneration in cortical grey matter lesions. CONCLUSIONS Complement is activated in the MS cortical grey matter lesions in areas of elevated numbers of complement receptor-positive microglia and suggests that complement over-activation may contribute to the worsening pathology that underlies the irreversible progression of MS.
Collapse
Affiliation(s)
- Lewis M Watkins
- Institute of Life Sciences, Swansea University School of Medicine, Swansea, SA2 8PP, UK
| | - James W Neal
- Institute of Infection and Immunity, Cardiff University, Cardiff, UK
| | - Sam Loveless
- Institute of Psychological Medicine and Clinical Neuroscience, Cardiff University, Cardiff, UK
| | - Iliana Michailidou
- Department of Genome Analysis, Academic Medical Centre, Amsterdam, The Netherlands
| | - Valeria Ramaglia
- Department of Genome Analysis, Academic Medical Centre, Amsterdam, The Netherlands
| | - Mark I Rees
- Institute of Life Sciences, Swansea University School of Medicine, Swansea, SA2 8PP, UK
| | | | - Neil P Robertson
- Institute of Psychological Medicine and Clinical Neuroscience, Cardiff University, Cardiff, UK
| | - B Paul Morgan
- Institute of Infection and Immunity, Cardiff University, Cardiff, UK
| | - Owain W Howell
- Institute of Life Sciences, Swansea University School of Medicine, Swansea, SA2 8PP, UK. .,Division of Brain Sciences, Imperial College London, London, UK.
| |
Collapse
|
11
|
Michailidou I, Willems JGP, Kooi EJ, van Eden C, Gold SM, Geurts JJG, Baas F, Huitinga I, Ramaglia V. Complement C1q-C3-associated synaptic changes in multiple sclerosis hippocampus. Ann Neurol 2015; 77:1007-26. [PMID: 25727254 DOI: 10.1002/ana.24398] [Citation(s) in RCA: 179] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Revised: 02/20/2015] [Accepted: 02/22/2015] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Multiple sclerosis (MS) is a demyelinating disease of the central nervous system, leading to memory impairment in up to 65% of patients. Memory dysfunction in MS has been associated with loss of synapses in the hippocampus, but its molecular basis is unknown. Accumulating evidence suggests that components of the complement system, C1q and C3, can mediate elimination of synapses. METHODS To investigate the involvement of complement in synaptic changes in MS, gene and protein expression and localization of C1q and C3 were analyzed in relation to neuropathological changes in myelinated and demyelinated hippocampi from postmortem MS brains. Findings were compared to hippocampi of Alzheimer disease (AD) and non-neurological controls. RESULTS C1q expression and C3 activation were increased in myelinated and demyelinated MS hippocampi, mainly in the CA3/2 and CA1 subfields, which also showed a marked decrease in synaptic density and increased neuronal staining for the mitochondrial heat shock protein 70 (mtHSP70) stress marker. Neurons were the major source of C1q mRNA. C1q protein and activated C3 localized at synapses within human leukocyte antigen-positive cell processes and lysosomes, suggesting engulfment of complement-tagged synapses by microglia. A significant association (p < 0.0001) between the density of C1q and synaptophysin-positive synapses or mtHSP70 was seen in myelinated MS hippocampi, further pointing toward a link between the complement pathway and synaptic changes. In contrast to AD, MS hippocampi were consistently negative for the terminal complement activation complex C5b9. INTERPRETATION These data support a role for the C1q-C3 complement axis in synaptic alterations in the MS hippocampus.
Collapse
Affiliation(s)
- Iliana Michailidou
- Department of Genome Analysis, Academic Medical Center, Amsterdam, the Netherlands
| | - Janske G P Willems
- Department of Genome Analysis, Academic Medical Center, Amsterdam, the Netherlands.,Department of Neuroimmunology, Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
| | - Evert-Jan Kooi
- Department of Anatomy and Neurosciences, VU University Medical Center, Amsterdam, the Netherlands
| | - Corbert van Eden
- Department of Neuroimmunology, Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
| | - Stefan M Gold
- Center for Molecular Neurobiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Department of Psychiatry, Charité, Berlin, Germany
| | - Jeroen J G Geurts
- Department of Anatomy and Neurosciences, VU University Medical Center, Amsterdam, the Netherlands
| | - Frank Baas
- Department of Genome Analysis, Academic Medical Center, Amsterdam, the Netherlands
| | - Inge Huitinga
- Department of Neuroimmunology, Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
| | - Valeria Ramaglia
- Department of Genome Analysis, Academic Medical Center, Amsterdam, the Netherlands.,Department of Neuroimmunology, Netherlands Institute for Neuroscience, Amsterdam, the Netherlands
| |
Collapse
|
12
|
Ramaglia V, Jackson SJ, Hughes TR, Neal JW, Baker D, Morgan BP. Complement activation and expression during chronic relapsing experimental autoimmune encephalomyelitis in the Biozzi ABH mouse. Clin Exp Immunol 2015; 180:432-41. [PMID: 25619542 DOI: 10.1111/cei.12595] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/20/2015] [Indexed: 12/29/2022] Open
Abstract
Chronic relapsing experimental autoimmune encephalomyelitis (crEAE) in mice recapitulates many of the clinical and histopathological features of human multiple sclerosis (MS), making it a preferred model for the disease. In both, adaptive immunity and anti-myelin T cells responses are thought to be important, while in MS a role for innate immunity and complement has emerged. Here we sought to test whether complement is activated in crEAE and important for disease. Disease was induced in Biozzi ABH mice that were terminated at different stages of the disease to assess complement activation and local complement expression in the central nervous system. Complement activation products were abundant in all spinal cord areas examined in acute disease during relapse and in the progressive phase, but were absent in early disease remission, despite significant residual clinical disease. Local expression of C1q and C3 was increased at all stages of disease, while C9 expression was increased only in acute disease; expression of the complement regulators CD55, complement receptor 1-related gene/protein y (Crry) and CD59a was reduced at all stages of the disease compared to naive controls. These data show that complement is activated in the central nervous system in the model and suggest that it is a suitable candidate for exploring whether anti-complement agents might be of benefit in MS.
Collapse
Affiliation(s)
- V Ramaglia
- Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - S J Jackson
- Neuroinflammation, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - T R Hughes
- Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - J W Neal
- Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| | - D Baker
- Neuroinflammation, Blizard Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - B P Morgan
- Institute of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, UK
| |
Collapse
|
13
|
Malekzadeh A, Teunissen C. Recent progress in omics-driven analysis of MS to unravel pathological mechanisms. Expert Rev Neurother 2014; 13:1001-16. [PMID: 24053344 DOI: 10.1586/14737175.2013.835602] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
At present, the pathophysiology and specific biological markers reflecting pathology of multiple sclerosis (MS) remain undetermined. The risk of developing MS is considered to depend on genetic susceptibility and environmental factors. The interaction of environmental factors with epigenetic mechanisms could affect the transcriptional level and therefore also the translational level. In the last decade, growing amount of hypothesis-free 'omics' studies have shed light on the potential MS mechanisms and raised potential biomarker targets. To understand MS pathophysiology and discover a subset of biomarkers, it is becoming essential to take a step forward and integrate the findings of the different fields of 'omics' into a systems biology network. In this review, we will discuss the recent findings of the genomic, transcriptomic and proteomic fields for MS and aim to make a unifying model.
Collapse
Affiliation(s)
- Arjan Malekzadeh
- Department of Clinical Chemistry, VU University Medical Center, De Boelelaan 1117, 1081 HV Amsterdam, The Netherlands
| | | |
Collapse
|
14
|
Hendrickx DAE, Schuurman KG, van Draanen M, Hamann J, Huitinga I. Enhanced uptake of multiple sclerosis-derived myelin by THP-1 macrophages and primary human microglia. J Neuroinflammation 2014; 11:64. [PMID: 24684721 PMCID: PMC4108133 DOI: 10.1186/1742-2094-11-64] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 03/09/2014] [Indexed: 01/23/2023] Open
Abstract
Background The pathological hallmark of multiple sclerosis (MS) is myelin phagocytosis. It remains unclear why microglia and macrophages demyelinate axons in MS, but previously found or yet-unknown changes in the myelin of MS patients could contribute to this process. We therefore studied whether myelin from normal-appearing white matter (NAWM) of MS donors is phagocytosed more efficiently than myelin from control donors. Methods Myelin was isolated from 11 MS and 12 control brain donors and labeled with the pH-sensitive fluorescent dye pHrodo to quantify uptake in lysosomes. Phagocytosis by differentiated THP-1 macrophages and by primary human microglia was quantified with flow cytometry. Whereas myelin uptake by THP-1 macrophages reached a plateau after approximately 24 hours, uptake by primary human microglia showed an almost linear increase over a 72–hour period. Data were statistically analyzed with the Mann–Whitney U test. Results MS-derived myelin was phagocytosed more efficiently by THP-1 macrophages after 6-hour incubation (P = 0.001 for the percentage of myelin-phagocytosing cells and P = 0.0005 for total myelin uptake) and after 24-hour incubation (P = 0.0006 and P = 0.0001, respectively), and by microglia after 24-hour incubation (P = 0.0106 for total myelin uptake). This enhanced uptake was not due to differences in the oxidation status of the myelin. Interestingly, myelin phagocytosis correlated negatively with the age of myelin donors, whereas the age of microglia donors showed a positive trend with myelin phagocytosis. Conclusions Myelin isolated from normal-appearing white matter of MS donors was phagocytosed more efficiently than was myelin isolated from control brain donors by both THP-1 macrophages and primary human microglia. These data indicate that changes in MS myelin might precede phagocyte activation and subsequent demyelination in MS. Identifying these myelin changes responsible for enhancing phagocytic ability could be an interesting therapeutic target to prevent or inhibit formation or expansion of MS lesions. Moreover, during aging, microglia enhance their phagocytic capacity for myelin phagocytosis, but myelin reduces its susceptibility for uptake.
Collapse
Affiliation(s)
| | | | | | | | - Inge Huitinga
- Neuroimmunology Research Group, Netherlands Institute for Neuroscience, Meibergdreef 47, 1105 BA Amsterdam, The Netherlands.
| |
Collapse
|
15
|
Veerhuis R, Nielsen HM, Tenner AJ. Complement in the brain. Mol Immunol 2011; 48:1592-603. [PMID: 21546088 PMCID: PMC3142281 DOI: 10.1016/j.molimm.2011.04.003] [Citation(s) in RCA: 316] [Impact Index Per Article: 22.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 04/04/2011] [Accepted: 04/04/2011] [Indexed: 01/24/2023]
Abstract
The brain is considered to be an immune privileged site, because the blood-brain barrier limits entry of blood borne cells and proteins into the central nervous system (CNS). As a result, the detection and clearance of invading microorganisms and senescent cells as well as surplus neurotransmitters, aged and glycated proteins, in order to maintain a healthy environment for neuronal and glial cells, is largely confined to the innate immune system. In recent years it has become clear that many factors of innate immunity are expressed throughout the brain. Neuronal and glial cells express Toll like receptors as well as complement receptors, and virtually all complement components can be locally produced in the brain, often in response to injury or developmental cues. However, as inflammatory reactions could interfere with proper functioning of the brain, tight and fine tuned regulatory mechanisms are warranted. In age related diseases, such as Alzheimer's disease (AD), accumulating amyloid proteins elicit complement activation and a local, chronic inflammatory response that leads to attraction and activation of glial cells that, under such activation conditions, can produce neurotoxic substances, including pro-inflammatory cytokines and oxygen radicals. This process may be exacerbated by a disturbed balance between complement activators and complement regulatory proteins such as occurs in AD, as the local synthesis of these proteins is differentially regulated by pro-inflammatory cytokines. Much knowledge about the role of complement in neurodegenerative diseases has been derived from animal studies with transgenic overexpressing or knockout mice for specific complement factors or receptors. These studies have provided insight into the potential therapeutic use of complement regulators and complement receptor antagonists in chronic neurodegenerative diseases as well as in acute conditions, such as stroke. Interestingly, recent animal studies have also indicated that complement activation products are involved in brain development and synapse formation. Not only are these findings important for the understanding of how brain development and neural network formation is organized, it may also give insights into the role of complement in processes of neurodegeneration and neuroprotection in the injured or aged and diseased adult central nervous system, and thus aid in identifying novel and specific targets for therapeutic intervention.
Collapse
Affiliation(s)
- Robert Veerhuis
- Depts of Clinical Chemistry, Pathology, Psychiatry and Alzheimer Center, VU, University Medical Center, Amsterdam, The Netherlands
| | - Henrietta M. Nielsen
- Dept of Clinical Sciences Malmö, Molecular Memory Research Unit, Lund University, The Wallenberg Lab 2floor, Skåne University Hospital entrance 46, Malmö, Sweden
| | - Andrea J. Tenner
- Depts of Molecular Biology and Biochemistry and Neurobiology and Behavior, Institute for Immunology, UCI MIND, University of California, Irvine, USA
| |
Collapse
|
16
|
Tüzün E, Kürtüncü M, Türkoğlu R, Içöz S, Pehlivan M, Birişik O, Eraksoy M, Akman-Demir G. Enhanced complement consumption in neuromyelitis optica and Behçet's disease patients. J Neuroimmunol 2011; 233:211-5. [PMID: 21215465 DOI: 10.1016/j.jneuroim.2010.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Revised: 10/08/2010] [Accepted: 11/27/2010] [Indexed: 10/18/2022]
Abstract
The complement system is essential in the pathogenesis of inflammatory central nervous system disorders. To investigate the involvement of complement pathways in neuromyelitis optica (NMO), levels of breakdown products for classical (C4d), alternative (FBb) and common (sC5b-9) pathways were measured in the sera of 28 NMO and control patients (30 Behçet's disease (BD), 29 multiple sclerosis (MS)) and 31 healthy controls by ELISA. Classical and/or alternative pathway consumption was enhanced in NMO and BD patients as compared to MS patients and healthy controls. Our results suggest that NBD and NMO differ from MS by the predominance of complement system involvement.
Collapse
Affiliation(s)
- Erdem Tüzün
- Istanbul University, Istanbul Faculty of Medicine, Department of Neurology, Istanbul, Turkey.
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Zeis T, Kinter J, Herrero-Herranz E, Weissert R, Schaeren-Wiemers N. Gene expression analysis of normal appearing brain tissue in an animal model for multiple sclerosis revealed grey matter alterations, but only minor white matter changes. J Neuroimmunol 2008; 205:10-9. [DOI: 10.1016/j.jneuroim.2008.09.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Revised: 07/29/2008] [Accepted: 09/04/2008] [Indexed: 10/21/2022]
|
18
|
|
19
|
Breij ECW, Brink BP, Veerhuis R, van den Berg C, Vloet R, Yan R, Dijkstra CD, van der Valk P, Bö L. Homogeneity of active demyelinating lesions in established multiple sclerosis. Ann Neurol 2008; 63:16-25. [PMID: 18232012 DOI: 10.1002/ana.21311] [Citation(s) in RCA: 241] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
OBJECTIVE Four different patterns of demyelination have been described in active demyelinating lesions of multiple sclerosis (MS) patients that were biopsied shortly after disease onset. These patterns were suggested to represent heterogeneity of the underlying pathogenesis. The aim of this study was to determine whether lesion heterogeneity also exists in an unselected collection of autopsy material from patients with established MS. METHODS All MS brain tissue available in the VU Medical Center was assessed for the presence of active demyelinating lesions using magnetic resonance imaging-guided sampling and immunohistochemistry. Tissue blocks containing active demyelinating lesions were evaluated for the presence of complement and antibody deposition, oligodendrocyte apoptosis, differential loss of myelin proteins, and hypoxia-like damage using histology, immunohistochemistry, and confocal microscopy. Blocks with active demyelinating lesions were compared with blocks with active (nondemyelinating) and inactive lesions. RESULTS Complement and antibodies were consistently associated with macrophages in areas of active demyelination. Preferential loss of myelin proteins, extensive hypoxia-like damage, and oligodendrocyte apoptosis were absent or rare. This pattern was observed in all tissue blocks containing active demyelinating lesions; lesion heterogeneity between patients was not found. INTERPRETATION The immunopathological appearance of active demyelinating lesions in established MS is uniform. Initial heterogeneity of demyelinating lesions in the earliest phase of MS lesion formation may disappear over time as different pathways converge in one general mechanism of demyelination. Consistent presence of complement, antibodies, and Fcgamma receptors in phagocytic macrophages suggests that antibody- and complement-mediated myelin phagocytosis is the dominant mechanism of demyelination in established MS.
Collapse
Affiliation(s)
- Esther C W Breij
- Department of Molecular Cell Biology and Immunology, Vrije Universiteit Medical Center, Amsterdam, The Netherlands
| | | | | | | | | | | | | | | | | |
Collapse
|
20
|
You Z, Yang J, Takahashi K, Yager PH, Kim HH, Qin T, Stahl GL, Ezekowitz RAB, Carroll MC, Whalen MJ. Reduced tissue damage and improved recovery of motor function after traumatic brain injury in mice deficient in complement component C4. J Cereb Blood Flow Metab 2007; 27:1954-64. [PMID: 17457366 DOI: 10.1038/sj.jcbfm.9600497] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Complement component C4 mediates C3-dependent tissue damage after systemic ischemia-reperfusion injury. Activation of C3 also contributes to the pathogenesis of experimental and human traumatic brain injury (TBI); however, few data exist regarding the specific pathways (classic, alternative, and lectin) involved. Using complement knockout mice and a controlled cortical impact (CCI) model, we tested the hypothesis that the classic pathway mediates secondary damage after TBI. After CCI, C4c and C3d immunostaining were detected in cortical vascular endothelial cells in wild-type (WT) mice; however, C4c and C3d immunostaining were also detected in C1q(-/-) mice, and C3d immunostaining was detected in C4(-/-) mice. After CCI, WT and C1q(-/-) mice had similar motor deficits, Morris water maze performance, and brain lesion size. Naive C4(-/-) and WT mice did not differ in baseline motor performance, but C4(-/-) mice had reduced postinjury motor deficits (days 1 to 7, P<0.05) and decreased brain tissue damage (days 14 and 35, P<0.05) versus WT. Reconstitution of C4(-/-) mice with human C4 (hC4) reversed their protection against postinjury motor deficits (P<0.05 versus vehicle), but administration of hC4 did not impair postinjury motor performance (versus vehicle) in WT mice. The protective effects of C4(-/-) were functionally distinct from the classic pathway and terminal complement, as C1q(-/-) and C3(-/-) mice had postinjury tissue damage and motor dysfunction similar to WT. Thus, C4 contributes to motor deficits and brain tissue damage after CCI by mechanism(s) fundamentally different from those involved in experimental systemic ischemia-reperfusion injury.
Collapse
Affiliation(s)
- Zerong You
- Neuroscience Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts 02129, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Bannerman P, Horiuchi M, Feldman D, Hahn A, Itoh A, See J, Jia ZP, Itoh T, Pleasure D. GluR2-free alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate receptors intensify demyelination in experimental autoimmune encephalomyelitis. J Neurochem 2007; 102:1064-70. [PMID: 17472701 DOI: 10.1111/j.1471-4159.2007.04612.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We adopted a genetic approach to test the importance of edited GluR2-free, Ca(2+)-permeable, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) receptors in the pathophysiology of experimental autoimmune encephalomyelitis, an inflammatory demyelinative disorder resembling multiple sclerosis. Initial studies showed that oligodendroglial lineage cells from mice lacking functional copies of the gene encoding the GluR3 AMPA receptor subunit (Gria3) had a diminished capacity to assemble edited GluR2-free AMPA receptors, and were resistant to excitotoxicity in vitro. Neurological deficits and spinal cord demyelination elicited by immunization with myelin oligodendrocyte glycoprotein peptide were substantially milder in these Gria3 mutant mice than in their wild-type littermates. These results support the hypothesis that oligodendroglial excitotoxicity mediated by AMPA receptors that do not contain edited GluR2 subunits contributes to demyelination in experimental autoimmune encephalomyelitis, and suggest that inhibiting these Ca(2+)-permeable AMPA receptors would be therapeutic in multiple sclerosis.
Collapse
MESH Headings
- Animals
- Animals, Newborn
- Brain/cytology
- Brain/metabolism
- Brain/pathology
- Cells, Cultured
- Demyelinating Diseases/genetics
- Demyelinating Diseases/pathology
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Encephalomyelitis, Autoimmune, Experimental/physiopathology
- Excitatory Amino Acid Agents/pharmacology
- Female
- Gene Expression Regulation/genetics
- Kainic Acid/pharmacology
- Membrane Potentials/drug effects
- Membrane Potentials/physiology
- Mice
- Mice, Knockout
- Neuroglia/physiology
- Patch-Clamp Techniques/methods
- RNA, Messenger/biosynthesis
- Receptors, AMPA/deficiency
- Receptors, AMPA/metabolism
- Receptors, Glutamate/genetics
- Receptors, Glutamate/metabolism
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Spermine/analogs & derivatives
- Spermine/pharmacology
- Statistics, Nonparametric
Collapse
Affiliation(s)
- Peter Bannerman
- UC Davis School of Medicine, Shriners Hospital, Sacramento, California 95817, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
22
|
Albert M, Antel J, Brück W, Stadelmann C. Extensive cortical remyelination in patients with chronic multiple sclerosis. Brain Pathol 2007; 17:129-38. [PMID: 17388943 PMCID: PMC8095564 DOI: 10.1111/j.1750-3639.2006.00043.x] [Citation(s) in RCA: 222] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Recent studies revealed prominent cortical demyelination in patients with chronic multiple sclerosis (MS). Demyelination in white matter lesions is frequently accompanied by remyelination. This repair process, however, often remains incomplete and restricted to the lesion border. In the present study, we examined the frequency and extent of remyelination in cortical and white matter lesions in autopsy brain tissue of 33 patients with chronic MS. The majority of patients (29 of 33) harbored cortical demyelination. Remyelination of cortical lesions was identified light microscopically by the presence of thin and irregularly arranged myelin sheaths, and confirmed by electron microscopy. Extensive remyelination was found in 18%, remyelination restricted to the lesion border in 54%, and no remyelination in 28% of cortical lesions. A direct comparison of the extent of remyelination in white matter and cortical lesions of the same patients revealed that remyelination of cortical lesions was consistently more extensive. In addition, g-ratios of fibers in areas of "normal appearing cortex" yielded values consistent with remyelination. Our data confirm the high prevalence of cortical demyelination in chronic MS and imply that the propensity to remyelinate is high in cortical MS lesions.
Collapse
Affiliation(s)
- Monika Albert
- Institute of Neuropathology, University of Goettingen, Goettingen, Germany
| | - Jack Antel
- Department of Neurology and Neurosurgery, McGill University, Montreal, Canada
| | - Wolfgang Brück
- Institute of Neuropathology, University of Goettingen, Goettingen, Germany
- Institute for Multiple Sclerosis Research, University of Goettingen and Gemeinnuetzige Hertie‐Stiftung, Goettingen, Germany
| | | |
Collapse
|
23
|
Hinman JD, Abraham CR. What's behind the decline? The role of white matter in brain aging. Neurochem Res 2007; 32:2023-31. [PMID: 17447140 DOI: 10.1007/s11064-007-9341-x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Accepted: 03/23/2007] [Indexed: 02/05/2023]
Abstract
The specific molecular events that underlie the age-related loss of cognitive function are poorly understood. Although not experimentally substantiated, age-dependent neuronal loss has long been considered central to age-related cognitive decline. More recently, age-related changes in brain white matter have taken precedence in explaining the steady decline in cognitive domains seen in non-diseased elderly. Characteristic alterations in the ultrastructure of myelin coupled with evidence of inflammatory processes present in the white matter of several different species suggest that specific molecular events within brain white matter may better explain observed pathological changes and cognitive deficits. This review focuses on recent evidence highlighting the importance of white matter in deciphering the course of "normal" brain aging.
Collapse
Affiliation(s)
- Jason D Hinman
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02118, USA
| | | |
Collapse
|
24
|
Ankeny DP, Lucin KM, Sanders VM, McGaughy VM, Popovich PG. Spinal cord injury triggers systemic autoimmunity: evidence for chronic B lymphocyte activation and lupus-like autoantibody synthesis. J Neurochem 2007; 99:1073-87. [PMID: 17081140 DOI: 10.1111/j.1471-4159.2006.04147.x] [Citation(s) in RCA: 119] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Clinical and experimental data indicate that spinal cord injury (SCI) elicits pathological T-cell responses. Implicit in these data, but poorly understood, is that B lymphocytes (B cells) also contribute to the delayed pathophysiology of spinal trauma. Here, for the first time, we show that experimental spinal contusion injury elicits chronic systemic and intraspinal B cell activation with the emergence of a B cell-dependent organ-specific and systemic autoimmune response. Specifically, using sera from spinal cord injured mice, immunoblots reveal oligoclonal IgG reactivity against multiple CNS proteins. We also show SCI-induced synthesis of autoantibodies that bind nuclear antigens including DNA and RNA. Elevated levels of anti-DNA antibodies are a distinguishing feature of systemic lupus erythematosus and, via their ability to cross-react with neuronal antigens, can cause neuropathology. We show a similar pathologic potential for the autoantibodies produced after SCI. Thus, mammalian SCI produces marked dysregulation of B cell function (i.e. autoimmunity) with pathological potential.
Collapse
Affiliation(s)
- Daniel P Ankeny
- Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University College of Medicine, Columbus, Ohio 43210, USA
| | | | | | | | | |
Collapse
|
25
|
Urich E, Gutcher I, Prinz M, Becher B. Autoantibody-mediated demyelination depends on complement activation but not activatory Fc-receptors. Proc Natl Acad Sci U S A 2006; 103:18697-702. [PMID: 17121989 PMCID: PMC1693725 DOI: 10.1073/pnas.0607283103] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The precise mechanisms leading to CNS inflammation and myelin destruction in both multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) remain the subject of intense debate. In both MS and EAE, autoantibodies (autoAbs) are thought to be involved in tissue destruction through recruiting Fc receptor (FcR)-bearing cells or direct cytotoxic effects through the activation of the complement pathway. Whereas intrathecal immunoglobulin (Ig) production and Ig deposition in inflammatory lesions is a hallmark of MS, mice deficient in B cells and Igs develop severe EAE. Paradoxically, mice of the same genetic background but deficient in FcRgamma are EAE-resistant. We found that the functional expression of FcRgamma on systemic accessory cells, but not CNS-resident cells, appears to be vital for the development of CNS inflammation, independent of antigen-presenting cell function or Ab involvement. On the other hand, we found that the injection of antimyelin oligodendrocyte glycoprotein-Abs drastically worsens disease severity, inflammation, and demyelination. Using FcRgamma(-/-) and C1q(-/-) mice, we could definitively establish that the demyelinating capacity of such autoAb in vivo relies entirely on complement activation and is FcR-independent.
Collapse
MESH Headings
- Animals
- Autoantibodies/physiology
- Complement Activation/genetics
- Complement Activation/immunology
- Complement System Proteins/physiology
- Encephalomyelitis, Autoimmune, Experimental/immunology
- Encephalomyelitis, Autoimmune, Experimental/metabolism
- Encephalomyelitis, Autoimmune, Experimental/pathology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Mice, Transgenic
- Receptors, IgG/deficiency
- Receptors, IgG/genetics
- Receptors, IgG/physiology
Collapse
Affiliation(s)
- Eduard Urich
- *Neurology Department, Division of Neuroimmunology, University of Zurich, Y44-J38/J42, Winterthurerstrasse 190, 8057 Zurich, Switzerland; and
| | - Ilona Gutcher
- *Neurology Department, Division of Neuroimmunology, University of Zurich, Y44-J38/J42, Winterthurerstrasse 190, 8057 Zurich, Switzerland; and
| | - Marco Prinz
- Department of Neuropathology, Georg-August-University, University of Göttingen, Robert-Koch-Strasse 40, 37075 Göttingen, Germany
| | - Burkhard Becher
- *Neurology Department, Division of Neuroimmunology, University of Zurich, Y44-J38/J42, Winterthurerstrasse 190, 8057 Zurich, Switzerland; and
- To whom correspondence should be addressed. E-mail:
| |
Collapse
|
26
|
Merkler D, Böscke R, Schmelting B, Czéh B, Fuchs E, Brück W, Stadelmann C. Differential macrophage/microglia activation in neocortical EAE lesions in the marmoset monkey. Brain Pathol 2006; 16:117-23. [PMID: 16768751 PMCID: PMC8095787 DOI: 10.1111/j.1750-3639.2006.00004.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Recent studies revealed an important involvement of the cerebral cortex in multiple sclerosis (MS) patients. Cortical lesions in MS were reported to be less inflammatory and to show less structural damage than white matter lesions. Animal models reflecting the histopathological hallmarks of cortical demyelinated lesions in MS are sparse. Induction of experimental autoimmune encephalomyelitis (EAE) in the common marmoset has turned out to be an attractive non-human-primate model for MS. In the present study we investigated the presence and detailed cellular composition of cortical inflammatory demyelinating pathology in the common marmoset upon immunization with myelin oligodendrocyte glycoprotein (MOG). Extensive cortical demyelination reflecting the topographically distinct cortical lesion types in MS patients was revealed by immunohistochemistry for myelin basic protein (MBP). We explored the density of T- and B-lymphocytes, MHC-II expressing macrophages/microglia cells and early activated macrophages (MRP14) at perivascular and parenchymal lesions sites in neocortex and subcortical white matter. Despite a similar density of perivascular inflammatory infiltrates in the demyelinated neocortex, a considerable lower fraction of macrophages was found to express MRP14 in the neocortex indicating a different activation pattern in cortical compared with white matter lesions. Furthermore, cortical EAE lesions in marmoset monkeys revealed immunoglobulin leakage and complement component C9 deposition in intracortical but not subpial demyelination. Our findings indicate that the inflammatory response, especially macrophage and microglia activation, may be regulated differently in gray matter areas in primate brain.
Collapse
Affiliation(s)
- Doron Merkler
- Department of Neuropathology, Georg-August University Göttingen, Göttingen, Germany.
| | | | | | | | | | | | | |
Collapse
|
27
|
Alberdi E, Sánchez-Gómez MV, Torre I, Domercq M, Pérez-Samartín A, Pérez-Cerdá F, Matute C. Activation of kainate receptors sensitizes oligodendrocytes to complement attack. J Neurosci 2006; 26:3220-8. [PMID: 16554473 PMCID: PMC6674098 DOI: 10.1523/jneurosci.3780-05.2006] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Glutamate excitotoxicity and complement attack have both been implicated separately in the generation of tissue damage in multiple sclerosis and in its animal model, experimental autoimmune encephalomyelitis. Here, we investigated whether glutamate receptor activation sensitizes oligodendrocytes to complement attack. We found that a brief incubation with glutamate followed by exposure to complement was lethal to oligodendrocytes in vitro and in freshly isolated optic nerves. Complement toxicity was induced by activation of kainate but not of AMPA receptors and was abolished by removing calcium from the medium during glutamate priming. Dose-response studies showed that sensitization to complement attack is induced by two distinct kainate receptor populations displaying high and low affinities for glutamate. Oligodendrocyte death by complement required the formation of the membrane attack complex, which in turn increased membrane conductance and induced calcium overload and mitochondrial depolarization as well as a rise in the level of reactive oxygen species. Treatment with the antioxidant Trolox and inhibition of poly(ADP-ribose) polymerase-1, but not of caspases, protected oligodendrocytes against damage induced by complement. These findings indicate that glutamate sensitization of oligodendrocytes to complement attack may contribute to white matter damage in acute and chronic neurological disorders.
Collapse
MESH Headings
- Animals
- Animals, Newborn
- Antioxidants/pharmacology
- Calcium/metabolism
- Cell Death/drug effects
- Cell Death/immunology
- Cell Membrane/drug effects
- Cell Membrane/immunology
- Cell Membrane/metabolism
- Cells, Cultured
- Complement System Proteins/immunology
- Complement System Proteins/metabolism
- Demyelinating Autoimmune Diseases, CNS/immunology
- Demyelinating Autoimmune Diseases, CNS/metabolism
- Demyelinating Autoimmune Diseases, CNS/physiopathology
- Dose-Response Relationship, Drug
- Glutamic Acid/metabolism
- Glutamic Acid/pharmacology
- Male
- Nerve Fibers, Myelinated/drug effects
- Nerve Fibers, Myelinated/immunology
- Nerve Fibers, Myelinated/metabolism
- Neurotoxins/metabolism
- Oligodendroglia/drug effects
- Oligodendroglia/immunology
- Oligodendroglia/metabolism
- Optic Nerve/drug effects
- Optic Nerve/immunology
- Optic Nerve/metabolism
- Oxidative Stress/drug effects
- Oxidative Stress/immunology
- Patch-Clamp Techniques
- Polynucleotide Adenylyltransferase/antagonists & inhibitors
- Polynucleotide Adenylyltransferase/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptors, Kainic Acid/agonists
- Receptors, Kainic Acid/metabolism
Collapse
|
28
|
Tenner AJ, Fonseca MI. The double-edged flower: roles of complement protein C1q in neurodegenerative diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2006; 586:153-76. [PMID: 16893071 DOI: 10.1007/0-387-34134-x_11] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A role for the complement cascade in AD neuropathology was hypothesized over a decade ago, and the results of a significant number of in vitro studies are consistent with the involvement of this pathway in AD pathogenesis (reviewed in). Since C1q is colocalized with thioflavine-positive plaques and the C5b-9 complement membrane attack complex is detected in AD brain at autopsy, it is reasonable to hypothesize that complement activation has a role in the manifestation of AD either by its lytic capacity or as a trigger of glial infiltration and initiation of potentially damaging inflammation. The observed diminished glial activation and reduced loss of neuronal integrity in a murine model overexpressing mutant human APP but lacking the ability to activate the classical complement cascade provide the first direct evidence for a detrimental role of C1q, and presumably activation of the classical complement pathway in an animal model of AD. Research is now focused on generating mouse models that more closely mimic the human disease, so that the role of complement activation and inflammation on the behavioral/learning and memory dysfunction that occurs in this disease can be assessed. In addition, candidate therapies such as targeted inhibition of complement activation will need to be tested in these animal models as a step toward treatment of humans with the disease. However, it is important that the potential for a protective effect of C1q early on in disease progression should not be overlooked. Rather, strategies that enhance or mimic the protective effects of C1q as well as strategies that inhibit the detrimental processes should be fully investigated.
Collapse
Affiliation(s)
- Andrea J Tenner
- Department of Molecular Biology, Center for Immunology, University of California, Irvine, CA 92697, USA
| | | |
Collapse
|
29
|
Duce JA, Hollander W, Jaffe R, Abraham CR. Activation of early components of complement targets myelin and oligodendrocytes in the aged rhesus monkey brain. Neurobiol Aging 2005; 27:633-44. [PMID: 15992964 DOI: 10.1016/j.neurobiolaging.2005.03.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2004] [Revised: 02/16/2005] [Accepted: 03/09/2005] [Indexed: 02/03/2023]
Abstract
The disruption and loss of myelin in the white matter are some of the major changes that occur in the brain with age. In vitro studies suggest a role of the complement system in the catabolic breakdown of myelin membranes. This study presents findings on activation of the early components of complement cascade in the brains of both young and aged rhesus monkeys with evidence of increased complement activation in aged animals. Complement containing oligodendrocytes (CAOs) containing C3d and C4d complement activation products bound to oligodendrocytes and myelinated fibers were found in the brain of normal young and old animals. The CAOs, which also contained activated microglia, were distributed throughout the whole brain and in significantly greater numbers in the aged monkeys. These findings, together with the demonstration of covalent binding of the C3 fragments to myelin, suggest the initiation of the complement cascade by myelin and oligodendrocytes, which are known classical complement activators. Activation of terminal complement components was not demonstrable in the CAOs. Taken together the findings support the concept that activation of early components of complement in the brain may be a normal biological process that involves the metabolism of myelin and oligodendrocytes and up-regulates with age.
Collapse
Affiliation(s)
- James A Duce
- Department of Biochemistry, Boston University School of Medicine, 715 Albany Street, K620, Boston, MA 02118, USA
| | | | | | | |
Collapse
|
30
|
Brink BP, Veerhuis R, Breij ECW, van der Valk P, Dijkstra CD, Bö L. The pathology of multiple sclerosis is location-dependent: no significant complement activation is detected in purely cortical lesions. J Neuropathol Exp Neurol 2005; 64:147-55. [PMID: 15751229 DOI: 10.1093/jnen/64.2.147] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Complement activation is known to occur in white matter multiple sclerosis (MS) lesions. It is thought to mediate oligodendrocyte/myelin damage and to be a marker of pathologic heterogeneity among individuals. Less is known about complement deposition in the gray matter in MS. The aim of this study was to characterize the presence and distribution of complement activation products in cortical MS lesions. Immunohistochemical staining was performed on cryostat sections from the brains of 22 MS patients and 5 nonneurologic control patients obtained at autopsy. Deposition of the complement activation products C1q, C3d, and C5b-9 (membrane attack complex) was detected on and within macrophages/microglia and astrocytes and in blood vessel walls in white matter MS lesions. C3d and C4d were detected along myelin sheaths at the edge of the lesions. In the gray matter part of combined gray matter/white matter lesions complement activation was less frequent, but increased immunopositivity was detected for C3d on blood vessels, and for C3d and C4d on myelin at the border of lesions, when compared with control areas. In contrast, in the purely cortical lesions, the extent of complement deposition in general was low. In conclusion, the role of complement in MS pathogenesis seems lesion location-dependent.
Collapse
Affiliation(s)
- Bianca P Brink
- Department of Pathology, VU University Medical Center, Amsterdam, The Netherlands
| | | | | | | | | | | |
Collapse
|
31
|
Serrano-Fernández P, Ibrahim SM, Zettl UK, Thiesen HJ, Gödde R, Epplen JT, Möller S. Intergenomic consensus in multifactorial inheritance loci: the case of multiple sclerosis. Genes Immun 2005; 5:615-20. [PMID: 15573086 DOI: 10.1038/sj.gene.6364134] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Genetic linkage and association studies define chromosomal regions, quantitative trait loci (QTLs), which influence the phenotype of polygenic diseases. Here, we describe a global approach to determine intergenomic consensus of those regions in order to fine map QTLs and select particularly promising candidate genes for disease susceptibility or other polygenic traits. Exemplarily, human multiple sclerosis (MS) susceptibility regions were compared for sequence similarity with mouse and rat QTLs in its animal model experimental allergic encephalomyelitis (EAE). The number of intergenomic MS/EAE consensus genes (295) is significantly higher than expected if the animal model was unrelated to the human disease. Hence, this approach contributes to the empirical evaluation of animal models for their applicability to the study of human diseases.
Collapse
Affiliation(s)
- P Serrano-Fernández
- Institute of Immunology, University of Rostock, Schillingallee 70, 18055 Rostock, Germany.
| | | | | | | | | | | | | |
Collapse
|
32
|
Hosokawa M, Klegeris A, McGeer PL. Human oligodendroglial cells express low levels of C1 inhibitor and membrane cofactor protein mRNAs. J Neuroinflammation 2004; 1:17. [PMID: 15327690 PMCID: PMC516791 DOI: 10.1186/1742-2094-1-17] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2004] [Accepted: 08/24/2004] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND: Oligodendrocytes, neurons, astrocytes, microglia, and endothelial cells are capable of synthesizing complement inhibitor proteins. Oligodendrocytes are vulnerable to complement attack, which is particularly observed in multiple sclerosis. This vulnerability may be related to a deficiency in their ability to express complement regulatory proteins. METHODS: This study compared the expression level of complement inhibitor mRNAs by human oligodendrocytes, astrocytes and microglia using semi-quantitative RT-PCR. RESULTS: Semi-quantitative RT-PCR analysis showed that C1 inhibitor (C1-inh) mRNA expression was dramatically lower in oligodendroglial cells compared with astrocytes and microglia. The mRNA expression level of membrane cofactor protein (MCP) by oligodendrocytes was also significantly lower than for other cell types. CONCLUSION: The lower mRNA expression of C1-inh and MCP by oligodendrocytes could contribute to their vulnerability in several neurodegenerative and inflammatory diseases of the central nervous system.
Collapse
Affiliation(s)
- Masato Hosokawa
- Kinsmen Laboratory of Neurological Research, University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Andis Klegeris
- Kinsmen Laboratory of Neurological Research, University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| | - Patrick L McGeer
- Kinsmen Laboratory of Neurological Research, University of British Columbia, 2255 Wesbrook Mall, Vancouver, BC, V6T 1Z3, Canada
| |
Collapse
|
33
|
Schwab C, Hosokawa M, McGeer PL. Transgenic mice overexpressing amyloid beta protein are an incomplete model of Alzheimer disease. Exp Neurol 2004; 188:52-64. [PMID: 15191802 DOI: 10.1016/j.expneurol.2004.03.016] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2003] [Revised: 12/10/2003] [Accepted: 03/12/2004] [Indexed: 11/28/2022]
Abstract
We compared lesions in elderly transgenic (tg) mice carrying the Swedish double mutation KM670/671NL with lesions in Alzheimer disease (AD) by histochemical and immunohistochemical techniques. Highly similar staining for beta-amyloid protein (Abeta) was observed in AD and the mouse models. The abundant amyloid deposits in tg mice were in a consolidated state as revealed by strong Congo red birefringence. In both tg mice and AD, amyloid deposits were ApoE-positive and were surrounded by activated astrocytes. However, Bielschowsky silver staining and immunostaining with tau antibodies revealed no neurofibrillary tangles (NFTs) in the mice as opposed to abundant NFTs in AD. The microglial pattern was also distinctly different. Tg mice had only weakly activated microglia, which expressed low levels of the complement receptor CD11b. They were gathered around the periphery of the deposits. In contrast, AD lesions had strongly activated microglia, which expressed high levels of CD11b. They were associated with the plaque core. Immunostaining for complement proteins was weak in tg mice but very strong in AD deposits. We conclude that the weak inflammatory response and absence of NFTs indicate that tg mice are only a limited model of AD. Therapeutic strategies for the treatment of AD based on tg mouse models that overexpress Abeta may be limited in their application.
Collapse
Affiliation(s)
- Claudia Schwab
- Kinsmen Laboratory of Neurological Research, Division of Neurology, University of British Columbia, Vancouver, BC, Canada V6T 1Z3
| | | | | |
Collapse
|
34
|
Hosokawa M, Klegeris A, Maguire J, McGeer PL. Expression of complement messenger RNAs and proteins by human oligodendroglial cells. Glia 2003; 42:417-23. [PMID: 12730962 DOI: 10.1002/glia.10234] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Neurons, astrocytes, microglia, and endothelial cells are capable of synthesizing most, if not all, of the complement proteins. Little is known, however, about the capacity of oligodendroglial cells to generate complement components. This study evaluated expression of complement mRNAs and their protein products by human oligodendrocytes. Cells were isolated and cultured from white matter of seven adult cases that had undergone surgical temporal lobe resection for epilepsy. Oligodendroglial cultures were characterized by the expression of such cell type-specific mRNAs as myelin proteolipid protein (PLP), oligodendrocyte-specific protein (OSP), and 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and were further characterized by immunostaining for such differentiation markers as myelin basic protein (MBP), PLP, CNPase, and O4. RT-PCR analysis showed that the oligodendroglial cells expressed detectable levels of complement mRNAs for the C1q B-chain, C1r, C1s, C2, C3, C4, C5, C6, C7, C8 gamma subunit, and C9. Immunostaining was positive for C1q, C1s, C2, C3, C4, C5, C6, C7, C8, and C9. Double immunostaining for the oligodendrocyte marker O4 and the complement protein C3 demonstrated that all O4-positive cells were also positive for C3, indicating constitutive C3 expression. These results indicate that oligodendroglial cells may be a source of complement proteins in human brain and thus could contribute to the pathogenesis of several neurodegenerative and inflammatory diseases of the CNS, such as Alzheimer's disease, multiple sclerosis, and progressive supranuclear palsy, where complement-activated oligodendrocytes are abundant.
Collapse
Affiliation(s)
- Masato Hosokawa
- Kinsmen Laboratory of Neurological Research, University of British Columbia, Vancouver, British Columbia, Canada
| | | | | | | |
Collapse
|