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: 0] [Impact Index Per Article: 0] [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
|
Liu YX, Yu Y, Liu JP, Liu WJ, Cao Y, Yan RM, Yao YM. Neuroimmune Regulation in Sepsis-Associated Encephalopathy: The Interaction Between the Brain and Peripheral Immunity. Front Neurol 2022; 13:892480. [PMID: 35832175 PMCID: PMC9271799 DOI: 10.3389/fneur.2022.892480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2022] [Accepted: 05/27/2022] [Indexed: 11/15/2022] Open
Abstract
Sepsis-associated encephalopathy (SAE), the most popular cause of coma in the intensive care unit (ICU), is the diffuse cerebral damage caused by the septic challenge. SAE is closely related to high mortality and extended cognitive impairment in patients in septic shock. At present, many studies have demonstrated that SAE might be mainly associated with blood–brain barrier damage, abnormal neurotransmitter secretion, oxidative stress, and neuroimmune dysfunction. Nevertheless, the precise mechanism which initiates SAE and contributes to the long-term cognitive impairment remains largely unknown. Recently, a growing body of evidence has indicated that there is close crosstalk between SAE and peripheral immunity. The excessive migration of peripheral immune cells to the brain, the activation of glia, and resulting dysfunction of the central immune system are the main causes of septic nerve damage. This study reviews the update on the pathogenesis of septic encephalopathy, focusing on the over-activation of immune cells in the central nervous system (CNS) and the “neurocentral–endocrine–immune” networks in the development of SAE, aiming to further understand the potential mechanism of SAE and provide new targets for diagnosis and management of septic complications.
Collapse
Affiliation(s)
- Yu-xiao Liu
- Translational Medicine Research Center, Medical Innovation Research Division and Fourth Medical Center of the Chinese PLA General Hospital, Beijing, China
- Department of Neurosurgery, The Chinese PLA General Hospital, Beijing, China
| | - Yang Yu
- Department of Traditional Chinese Medical Science, Sixth Medical Center of the Chinese PLA General Hospital, Beijing, China
| | - Jing-peng Liu
- Translational Medicine Research Center, Medical Innovation Research Division and Fourth Medical Center of the Chinese PLA General Hospital, Beijing, China
- Department of Traditional Chinese Medical Science, Sixth Medical Center of the Chinese PLA General Hospital, Beijing, China
| | - Wen-jia Liu
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences, Beijing Institute of Lifeomics, Beijing, China
| | - Yang Cao
- Department of Neurosurgery, The Chinese PLA General Hospital, Beijing, China
| | - Run-min Yan
- Department of Neurosurgery, The Chinese PLA General Hospital, Beijing, China
- *Correspondence: Yong-ming Yao
| | - Yong-ming Yao
- Translational Medicine Research Center, Medical Innovation Research Division and Fourth Medical Center of the Chinese PLA General Hospital, Beijing, China
- Run-min Yan
| |
Collapse
|
3
|
Mannes M, Schmidt CQ, Nilsson B, Ekdahl KN, Huber-Lang M. Complement as driver of systemic inflammation and organ failure in trauma, burn, and sepsis. Semin Immunopathol 2021; 43:773-788. [PMID: 34191093 PMCID: PMC8243057 DOI: 10.1007/s00281-021-00872-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 05/23/2021] [Indexed: 02/08/2023]
Abstract
Complement is one of the most ancient defense systems. It gets strongly activated immediately after acute injuries like trauma, burn, or sepsis and helps to initiate regeneration. However, uncontrolled complement activation contributes to disease progression instead of supporting healing. Such effects are perceptible not only at the site of injury but also systemically, leading to systemic activation of other intravascular cascade systems eventually causing dysfunction of several vital organs. Understanding the complement pathomechanism and its interplay with other systems is a strict requirement for exploring novel therapeutic intervention routes. Ex vivo models exploring the cross-talk with other systems are rather limited, which complicates the determination of the exact pathophysiological roles that complement has in trauma, burn, and sepsis. Literature reporting on these three conditions is often controversial regarding the importance, distribution, and temporal occurrence of complement activation products further hampering the deduction of defined pathophysiological pathways driven by complement. Nevertheless, many in vitro experiments and animal models have shown beneficial effects of complement inhibition at different levels of the cascade. In the future, not only inhibition but also a complement reconstitution therapy should be considered in prospective studies to expedite how meaningful complement-targeted interventions need to be tailored to prevent complement augmented multi-organ failure after trauma, burn, and sepsis. This review summarizes clinically relevant studies investigating the role of complement in the acute diseases trauma, burn, and sepsis with important implications for clinical translation.
Collapse
Affiliation(s)
- Marco Mannes
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital of Ulm, Helmholtzstr. 8/2, 89081, Ulm, Germany
| | - Christoph Q Schmidt
- Institute of Pharmacology of Natural Products and Clinical Pharmacology, Ulm University, Ulm, Germany
| | - Bo Nilsson
- Department of Immunology, Genetics and Pathology (IGP), Rudbeck Laboratory C5:3, Uppsala University, Uppsala, Sweden
| | - Kristina N Ekdahl
- Department of Immunology, Genetics and Pathology (IGP), Rudbeck Laboratory C5:3, Uppsala University, Uppsala, Sweden.,Linnaeus Center of Biomaterials Chemistry, Linnaeus University, Kalmar, Sweden
| | - Markus Huber-Lang
- Institute of Clinical and Experimental Trauma-Immunology, University Hospital of Ulm, Helmholtzstr. 8/2, 89081, Ulm, Germany.
| |
Collapse
|
4
|
Garred P, Tenner AJ, Mollnes TE. Therapeutic Targeting of the Complement System: From Rare Diseases to Pandemics. Pharmacol Rev 2021; 73:792-827. [PMID: 33687995 PMCID: PMC7956994 DOI: 10.1124/pharmrev.120.000072] [Citation(s) in RCA: 83] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The complement system was discovered at the end of the 19th century as a heat-labile plasma component that "complemented" the antibodies in killing microbes, hence the name "complement." Complement is also part of the innate immune system, protecting the host by recognition of pathogen-associated molecular patterns. However, complement is multifunctional far beyond infectious defense. It contributes to organ development, such as sculpting neuron synapses, promoting tissue regeneration and repair, and rapidly engaging and synergizing with a number of processes, including hemostasis leading to thromboinflammation. Complement is a double-edged sword. Although it usually protects the host, it may cause tissue damage when dysregulated or overactivated, such as in the systemic inflammatory reaction seen in trauma and sepsis and severe coronavirus disease 2019 (COVID-19). Damage-associated molecular patterns generated during ischemia-reperfusion injuries (myocardial infarction, stroke, and transplant dysfunction) and in chronic neurologic and rheumatic disease activate complement, thereby increasing damaging inflammation. Despite the long list of diseases with potential for ameliorating complement modulation, only a few rare diseases are approved for clinical treatment targeting complement. Those currently being efficiently treated include paroxysmal nocturnal hemoglobinuria, atypical hemolytic-uremic syndrome, myasthenia gravis, and neuromyelitis optica spectrum disorders. Rare diseases, unfortunately, preclude robust clinical trials. The increasing evidence for complement as a pathogenetic driver in many more common diseases suggests an opportunity for future complement therapy, which, however, requires robust clinical trials; one ongoing example is COVID-19 disease. The current review aims to discuss complement in disease pathogenesis and discuss future pharmacological strategies to treat these diseases with complement-targeted therapies. SIGNIFICANCE STATEMENT: The complement system is the host's defense friend by protecting it from invading pathogens, promoting tissue repair, and maintaining homeostasis. Complement is a double-edged sword, since when dysregulated or overactivated it becomes the host's enemy, leading to tissue damage, organ failure, and, in worst case, death. A number of acute and chronic diseases are candidates for pharmacological treatment to avoid complement-dependent damage, ranging from the well established treatment for rare diseases to possible future treatment of large patient groups like the pandemic coronavirus disease 2019.
Collapse
Affiliation(s)
- Peter Garred
- Laboratory of Molecular Medicine, Department of Clinical Immunology, Rigshospitalet, Copenhagen, Denmark, and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (P.G.); Departments of Molecular Biology and Biochemistry, Neurobiology and Behavior, and Pathology and Laboratory Medicine, University of California, Irvine, California (A.J.T.); and Research Laboratory, Nordland Hospital, Bodø, Norway, Faculty of Health Sciences, K.G. Jebsen TREC, University of Tromsø, Tromsø, Norway (T.E.M.); Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway (T.E.M.); and Department of Immunology, Oslo University Hospital and University of Oslo, Oslo, Norway (T.E.M.)
| | - Andrea J Tenner
- Laboratory of Molecular Medicine, Department of Clinical Immunology, Rigshospitalet, Copenhagen, Denmark, and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (P.G.); Departments of Molecular Biology and Biochemistry, Neurobiology and Behavior, and Pathology and Laboratory Medicine, University of California, Irvine, California (A.J.T.); and Research Laboratory, Nordland Hospital, Bodø, Norway, Faculty of Health Sciences, K.G. Jebsen TREC, University of Tromsø, Tromsø, Norway (T.E.M.); Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway (T.E.M.); and Department of Immunology, Oslo University Hospital and University of Oslo, Oslo, Norway (T.E.M.)
| | - Tom E Mollnes
- Laboratory of Molecular Medicine, Department of Clinical Immunology, Rigshospitalet, Copenhagen, Denmark, and Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark (P.G.); Departments of Molecular Biology and Biochemistry, Neurobiology and Behavior, and Pathology and Laboratory Medicine, University of California, Irvine, California (A.J.T.); and Research Laboratory, Nordland Hospital, Bodø, Norway, Faculty of Health Sciences, K.G. Jebsen TREC, University of Tromsø, Tromsø, Norway (T.E.M.); Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway (T.E.M.); and Department of Immunology, Oslo University Hospital and University of Oslo, Oslo, Norway (T.E.M.)
| |
Collapse
|
5
|
Park JW, Kim JE, Choi YJ, Kang MJ, Choi HJ, Bae SJ, Hong JT, Lee H, Hwang DY. Deficiency of complement component 3 may be linked to the development of constipation in FVB/N-C3 em1Hlee /Korl mice. FASEB J 2021; 35:e21221. [PMID: 33337564 DOI: 10.1096/fj.202000376r] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 11/03/2020] [Accepted: 11/10/2020] [Indexed: 12/15/2022]
Abstract
Alterations in complement component 3 (C3) expression has been reported to be linked to several bowel diseases including Crohn's disease, inflammatory bowel disease, and ulcerative colitis; however, the association with constipation has never been investigated. In this study, we aimed to investigate the correlation between C3 regulation and constipation development using a C3 deficiency model. To achieve these, alterations in stool excretion, transverse colon histological structure, and mucin secretion were analyzed in FVB/N-C3em1Hlee /Korl (C3 knockout, C3 KO) mice with the deletion of 11 nucleotides in exon 2 of the C3 gene. The stool excretion parameters, gastrointestinal transit, and intestine length were remarkably decreased in C3 KO mice compared with wild-type (WT) mice, although there was no specific change in feeding behavior. Furthermore, C3 KO mice showed a decrease in mucosal and muscle layer thickness, alterations in crypt structure, irregular distribution of goblet cells, and an increase of mucin droplets in the transverse colon. Mucin secretion was suppressed, and they accumulated in the crypts of C3 KO mice. In addition, the constipation phenotypes detected during C3 deficiency were confirmed in FVB/N mice treated with C3 convertase inhibitor (rosmarinic acid (RA)). Similar phenotypes were observed with respect to stool excretion parameters, gastrointestinal transit, intestine length, alterations in crypt structure, and mucin secretion in RA-treated FVB/N mice. Therefore, the results of the present study provide the first scientific evidence that C3 deficiency may play an important role in the development of constipation phenotypes in C3 KO mice.
Collapse
Affiliation(s)
- Ji Won Park
- Department of Biomaterials Science (BK21 FOUR Program), College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Ji Eun Kim
- Department of Biomaterials Science (BK21 FOUR Program), College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Yun Ju Choi
- Department of Biomaterials Science (BK21 FOUR Program), College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Mi Ju Kang
- Department of Biomaterials Science (BK21 FOUR Program), College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Hyeon Jun Choi
- Department of Biomaterials Science (BK21 FOUR Program), College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Su Ji Bae
- Department of Biomaterials Science (BK21 FOUR Program), College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| | - Jin Tae Hong
- College of Pharmacy, Chungbuk National University, Chungju, Korea
| | - Ho Lee
- Graduate School of Cancer Science and Policy, Research Institute, National Cancer Center, Goyang, Korea
| | - Dae Youn Hwang
- Department of Biomaterials Science (BK21 FOUR Program), College of Natural Resources & Life Science/Life and Industry Convergence Research Institute, Pusan National University, Miryang, Korea
| |
Collapse
|
6
|
Mollnes TE, Huber-Lang M. Complement in sepsis-when science meets clinics. FEBS Lett 2020; 594:2621-2632. [PMID: 32621378 DOI: 10.1002/1873-3468.13881] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 06/17/2020] [Accepted: 06/20/2020] [Indexed: 12/18/2022]
Abstract
Sepsis as life-threatening organ dysfunction caused by microorganisms represents a dreadful challenge for the immune system. The role of the complement system as major column of innate immunity has been extensively studied in various sepsis models, but its translational value remains in the dark. Complement activation products, such as C3a and C5a, and their corresponding receptors provide useful diagnostic tools and promising targets to improve organ function and outcome. However, a monotherapeutic complement intervention irrespective of the current immune function seems insufficient to reverse the complex sepsis mechanisms. Indeed, sepsis-induced disturbances of cross talking complement, coagulation, and fibrinolytic cascades lead to systemic 'thromboinflammation', ultimately followed by multiple-organ failure. We propose to reliably monitor the complement function in the patient and to re-establish the immune balance by patient-tailored combined therapies, such as complement and Toll-like receptor inhibition. Our working hypothesis aims at blocking the 'explosive' innate immune recognition systems early on before downstream mediators are released and the inflammatory response becomes irreversible, a strategy that we name 'upstream approach'.
Collapse
Affiliation(s)
- Tom E Mollnes
- Research Laboratory, Nordland Hospital Bodø, Bodø, Norway.,K. G. Jebsen TREC, University of Tromsø, Tromsø, Norway.,Department of Immunology, Oslo University Hospital, and University of Oslo, Oslo, Norway.,Centre of Molecular Inflammation Research, Norwegian University of Science and Technology, Trondheim, Norway
| | - Markus Huber-Lang
- Institute for Clinical and Experimental Trauma-Immunology, University Hospital Ulm, Ulm, Germany
| |
Collapse
|
7
|
The Role of Complement C3a Receptor in Stroke. Neuromolecular Med 2019; 21:467-473. [PMID: 31102134 DOI: 10.1007/s12017-019-08545-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 05/12/2019] [Indexed: 12/20/2022]
Abstract
The complement system is a key regulator of the innate immune response against diseased tissue that functions across multiple organ systems. Dysregulation of complement contributes to the pathogenesis of a number of neurological diseases including stroke. The C3a anaphylatoxin, via its cognate C3a receptor (C3aR), mediates inflammation by promoting breakdown of the blood-brain barrier and the massive infiltration of leukocytes into ischemic brain in experimental stroke models. Studies utilizing complement deficient mice as well as pharmacologic C3aR antagonists have shown a reduction in tissue injury and mortality in murine stroke models. The development of tissue-specific C3aR knockout mice and more specific C3aR antagonists is warranted to facilitate our understanding of the role of the C3aR in brain ischemia with the ultimate goal of clinical translation of therapies targeting C3aR in stroke patients.
Collapse
|
8
|
Ma Y, Liu Y, Zhang Z, Yang GY. Significance of Complement System in Ischemic Stroke: A Comprehensive Review. Aging Dis 2019; 10:429-462. [PMID: 31011487 PMCID: PMC6457046 DOI: 10.14336/ad.2019.0119] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 01/19/2019] [Indexed: 12/14/2022] Open
Abstract
The complement system is an essential part of innate immunity, typically conferring protection via eliminating pathogens and accumulating debris. However, the defensive function of the complement system can exacerbate immune, inflammatory, and degenerative responses in various pathological conditions. Cumulative evidence indicates that the complement system plays a critical role in the pathogenesis of ischemic brain injury, as the depletion of certain complement components or the inhibition of complement activation could reduce ischemic brain injury. Although multiple candidates modulating or inhibiting complement activation show massive potential for the treatment of ischemic stroke, the clinical availability of complement inhibitors remains limited. The complement system is also involved in neural plasticity and neurogenesis during cerebral ischemia. Thus, unexpected side effects could be induced if the systemic complement system is inhibited. In this review, we highlighted the recent concepts and discoveries of the roles of different kinds of complement components, such as C3a, C5a, and their receptors, in both normal brain physiology and the pathophysiology of brain ischemia. In addition, we comprehensively reviewed the current development of complement-targeted therapy for ischemic stroke and discussed the challenges of bringing these therapies into the clinic. The design of future experiments was also discussed to better characterize the role of complement in both tissue injury and recovery after cerebral ischemia. More studies are needed to elucidate the molecular and cellular mechanisms of how complement components exert their functions in different stages of ischemic stroke to optimize the intervention of targeting the complement system.
Collapse
Affiliation(s)
- Yuanyuan Ma
- 1Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Yanqun Liu
- 3Department of Neurology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Zhijun Zhang
- 2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Guo-Yuan Yang
- 1Department of Neurology, Ruijin Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,2Med-X Research Institute and School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| |
Collapse
|
9
|
Tchessalova D, Posillico CK, Tronson NC. Neuroimmune Activation Drives Multiple Brain States. Front Syst Neurosci 2018; 12:39. [PMID: 30210310 PMCID: PMC6123349 DOI: 10.3389/fnsys.2018.00039] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 08/07/2018] [Indexed: 12/11/2022] Open
Abstract
Neuroimmune signaling is increasingly identified as a critical component of neuronal processes underlying memory, emotion and cognition. The interactions of microglia and astrocytes with neurons and synapses, and the individual cytokines and immune signaling molecules that mediate these interactions are a current focus of much research. Here, we discuss neuroimmune activation as a mechanism triggering different states that modulate cognitive and affective processes to allow for appropriate behavior during and after illness or injury. We propose that these states lie on a continuum from a naïve homeostatic baseline state in the absence of stimulation, to acute neuroimmune activity and chronic activation. Importantly, consequences of illness or injury including cognitive deficits and mood impairments can persist long after resolution of immune signaling. This suggests that neuroimmune activation also results in an enduring shift in the homeostatic baseline state with long lasting consequences for neural function and behavior. Such different states can be identified in a multidimensional way, using patterns of cytokine and glial activation, behavioral and cognitive changes, and epigenetic signatures. Identifying distinct neuroimmune states and their consequences for neural function will provide a framework for predicting vulnerability to disorders of memory, cognition and emotion both during and long after recovery from illness.
Collapse
Affiliation(s)
- Daria Tchessalova
- Neuroscience Graduate Program, School of Medicine, University of Michigan, Ann Arbor, MI, United States
| | | | - Natalie Celia Tronson
- Neuroscience Graduate Program, School of Medicine, University of Michigan, Ann Arbor, MI, United States.,Department of Psychology, University of Michigan, Ann Arbor, MI, United States
| |
Collapse
|
10
|
Orhun G, Tüzün E, Özcan PE, Ulusoy C, Yildirim E, Küçükerden M, Gürvit H, Ali A, Esen F. Association Between Inflammatory Markers and Cognitive Outcome in Patients with Acute Brain Dysfunction Due to Sepsis. ACTA ACUST UNITED AC 2018; 56:63-70. [PMID: 30911240 DOI: 10.29399/npa.23212] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 06/01/2018] [Indexed: 12/13/2022]
Abstract
Introduction Sepsis-induced brain dysfunction (SIBD) has been neglected until recently due to the absence of specific clinical or biological markers. There is increasing evidence that sepsis may pose substantial risks for long term cognitive impairment. Methods To find out clinical and inflammatory factors associated with acute SIBD serum levels of cytokines, complement breakdown products and neurodegeneration markers were measured by ELISA in sera of 86 SIBD patients and 33 healthy controls. Association between these biological markers and cognitive test results was investigated. Results SIBD patients showed significantly increased IL-6, IL-8, IL-10 and C4 d levels and decreased TNF-α, IL-12, C5a and iC3b levels than healthy controls. No significant alteration was observed in neuronal loss and neurodegeneration marker [neuron specific enolase (NSE), amyloid β, tau] levels. Increased IL-1β, IL-6, IL-8, IL-10, TNF-α and decreased C4 d, C5a and iC3b levels were associated with septic shock, coma and mortality. Transient mild cognitive impairment was observed in 7 of 21 patients who underwent neuropsychological assessment. Cognitive dysfunction and neuronal loss were associated with increased duration of septic shock and delirium but not baseline serum levels of inflammation and neurodegeneration markers. Conclusion Increased cytokine levels, decreased complement activity and increased neuronal loss are indicators of poor prognosis and adverse events in SIBD. Cognitive dysfunction and neuronal destruction in SIBD do not seem to be associated with systemic inflammation factors and Alzheimer disease-type neurodegeneration but rather with increased duration of neuronal dysfunction and enhanced exposure of the brain to sepsis-inducing pathogens.
Collapse
Affiliation(s)
- Günseli Orhun
- Department of Anesthesiology and Reanimation, İstanbul University Faculty of Medicine, İstanbul, Turkey
| | - Erdem Tüzün
- Department of Neuroscience, Aziz Sancar Experimental Medicine Research Institute, İstanbul University, İstanbul, Turkey
| | - Perihan Ergin Özcan
- Department of Anesthesiology and Reanimation, İstanbul University Faculty of Medicine, İstanbul, Turkey
| | - Canan Ulusoy
- Department of Neuroscience, Aziz Sancar Experimental Medicine Research Institute, İstanbul University, İstanbul, Turkey
| | - Elif Yildirim
- Department of Neurology, İstanbul University Faculty of Medicine, İstanbul, Turkey
| | - Melike Küçükerden
- Department of Neuroscience, Aziz Sancar Experimental Medicine Research Institute, İstanbul University, İstanbul, Turkey
| | - Hakan Gürvit
- Department of Neurology, İstanbul University Faculty of Medicine, İstanbul, Turkey
| | - Achmet Ali
- Department of Anesthesiology and Reanimation, İstanbul University Faculty of Medicine, İstanbul, Turkey
| | - Figen Esen
- Department of Anesthesiology and Reanimation, İstanbul University Faculty of Medicine, İstanbul, Turkey
| |
Collapse
|
11
|
Hammad A, Westacott L, Zaben M. The role of the complement system in traumatic brain injury: a review. J Neuroinflammation 2018; 15:24. [PMID: 29357880 PMCID: PMC5778697 DOI: 10.1186/s12974-018-1066-z] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 01/15/2018] [Indexed: 02/08/2023] Open
Abstract
Traumatic brain injury (TBI) is an important cause of disability and mortality in the western world. While the initial injury sustained results in damage, it is the subsequent secondary cascade that is thought to be the significant determinant of subsequent outcomes. The changes associated with the secondary injury do not become irreversible until some time after the start of the cascade. This may present a window of opportunity for therapeutic interventions aiming to improve outcomes subsequent to TBI. A prominent contributor to the secondary injury is a multifaceted inflammatory reaction. The complement system plays a notable role in this inflammatory reaction; however, it has often been overlooked in the context of TBI secondary injury. The complement system has homeostatic functions in the uninjured central nervous system (CNS), playing a part in neurodevelopment as well as having protective functions in the fully developed CNS, including protection from infection and inflammation. In the context of CNS injury, it can have a number of deleterious effects, evidence for which primarily comes not only from animal models but also, to a lesser extent, from human post-mortem studies. In stark contrast to this, complement may also promote neurogenesis and plasticity subsequent to CNS injury. This review aims to explore the role of the complement system in TBI secondary injury, by examining evidence from both clinical and animal studies. We examine whether specific complement activation pathways play more prominent roles in TBI than others. We also explore the potential role of complement in post-TBI neuroprotection and CNS repair/regeneration. Finally, we highlight the therapeutic potential of targeting the complement system in the context of TBI and point out certain areas on which future research is needed.
Collapse
Affiliation(s)
- Adnan Hammad
- School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Laura Westacott
- Neuroscience and Mental Health Research Institute (NMHRI), School of Medicine, Cardiff University, Room 4FT 80E, 4th Floor, Heath Park, Cardiff, CF14 4XN UK
| | - Malik Zaben
- Neuroscience and Mental Health Research Institute (NMHRI), School of Medicine, Cardiff University, Room 4FT 80E, 4th Floor, Heath Park, Cardiff, CF14 4XN UK
| |
Collapse
|
12
|
Reginia A, Kucharska-Mazur J, Jabłoński M, Budkowska M, Dołȩgowska B, Sagan L, Misiak B, Ratajczak MZ, Rybakowski JK, Samochowiec J. Assessment of Complement Cascade Components in Patients With Bipolar Disorder. Front Psychiatry 2018; 9:614. [PMID: 30538645 PMCID: PMC6277457 DOI: 10.3389/fpsyt.2018.00614] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 11/01/2018] [Indexed: 12/14/2022] Open
Abstract
Introduction: The immune system is undoubtedly involved in the pathogenesis of various psychiatric disorders, such as schizophrenia, bipolar disorder, or depression. Although its role is not fully understood, it appears that this area of research can help to understand the etiology of mental illness. One of the components of the human immune system is the complement system, which forms a part of the innate immune response. Physiologically, except for its essential protective role, it is a vital element in the regeneration processes, including neurogenesis. To date, few studies have tried to clarify the role of the complement cascade in mental disorders. Materials and Methods: We evaluated concentrations of C3a, C5a, and C5b-9 complement cascade components in the peripheral blood of 30 patients suffering from bipolar disorder (BD) for at least 10 years, in euthymia, who were not treated with lithium salts. In addition, we divided our study sample into BD type I (BD-I, 22 persons), and BD type II (BD-II, 8 patients). The control group consisted of 30 healthy volunteers matched for age, sex, BMI, and smoking habits. Results: Compared to healthy controls, BD patients had elevated concentrations of all the investigated components. Furthermore, in patients with BD-II, we observed higher concentrations of C5b-9 as compared to patients with BD-I. However, there was a significant effect of BD diagnosis only on the levels of C3a and C5a but not on the level of C5b-9 after adjustment for potential confounding factors. Conclusions: Increased concentrations of components C3a and C5a of the complement system in the investigated group as compared to healthy controls suggest involvement of the complement cascade in the pathogenesis of BD, and provides further evidence of immune system dysregulation in BD patients.
Collapse
Affiliation(s)
- Artur Reginia
- Department of Psychiatry, Pomeranian Medical University, Szczecin, Poland
| | | | - Marcin Jabłoński
- Department of Psychiatry, Pomeranian Medical University, Szczecin, Poland
| | - Marta Budkowska
- Department of Medical Analytics, Pomeranian Medical University, Szczecin, Poland
| | - Barbara Dołȩgowska
- Department of Laboratory Medicine, Pomeranian Medical University, Szczecin, Poland
| | - Leszek Sagan
- Department of Neurosurgery, Pomeranian Medical University, Szczecin, Poland
| | - Błazej Misiak
- Department of Genetics, Wroclaw Medical University, Wrocław, Poland
| | - Mariusz Z Ratajczak
- Stem Cell Institute at James Graham Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - Janusz K Rybakowski
- Department of Adult Psychiatry, Poznan University of Medical Sciences, Poznan, Poland
| | - Jerzy Samochowiec
- Department of Psychiatry, Pomeranian Medical University, Szczecin, Poland
| |
Collapse
|
13
|
Larkin PB, Muchowski PJ. Genetic Deficiency of Complement Component 3 Does Not Alter Disease Progression in a Mouse Model of Huntington's Disease. J Huntingtons Dis 2016; 1:107-18. [PMID: 23097680 DOI: 10.3233/jhd-2012-120021] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Several genes and proteins of the complement cascade are present at elevated levels in brains of patients with Huntington's disease (HD). The complement cascade is well characterized as an effector arm of the immune system, and in the brain it is important for developmental synapse elimination. We hypothesized that increased levels of complement in HD brains contributes to disease progression, perhaps by contributing to synapse elimination or inflammatory signaling. We tested this hypothesis in the R6/2 mouse model of HD by crossing mice deficient in complement component 3 (C3), a crucial complement protein found at increased levels in HD brains, to R6/2 mice and monitoring behavioral and neuropathological disease progression. We found no alterations in multiple behavioral assays, weight or survival in R6/2 mice lacking C3. We also quantified the expression of several complement cascade genes in R6/2 brains and found that the large scale upregulation of complement genes observed in HD brains is not mirrored in R6/2 brains. These data show that C3 deficiency does not alter disease progression in the R6/2 mouse model of HD.
Collapse
Affiliation(s)
- Paul B Larkin
- Gladstone Institute of Neurological Disease, University of California, San Francisco, CA, USA
| | | |
Collapse
|
14
|
Alawieh A, Elvington A, Tomlinson S. Complement in the Homeostatic and Ischemic Brain. Front Immunol 2015; 6:417. [PMID: 26322048 PMCID: PMC4533015 DOI: 10.3389/fimmu.2015.00417] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 07/30/2015] [Indexed: 11/29/2022] Open
Abstract
The complement system is a component of the immune system involved in both recognition and response to pathogens, and it is implicated in an increasing number of homeostatic and disease processes. It is well documented that reperfusion of ischemic tissue results in complement activation and an inflammatory response that causes post-reperfusion injury. This occurs following cerebral ischemia and reperfusion and triggers secondary damage that extends beyond the initial infarcted area, an outcome that has rationalized the use of complement inhibitors as candidate therapeutics after stroke. In the central nervous system, however, recent studies have revealed that complement also has essential roles in synaptic pruning, neurogenesis, and neuronal migration. In the context of recovery after stroke, these apparent divergent functions of complement may account for findings that the protective effect of complement inhibition in the acute phase after stroke is not always maintained in the subacute and chronic phases. The development of effective stroke therapies based on modulation of the complement system will require a detailed understanding of complement-dependent processes in both early neurodegenerative events and delayed neuro-reparatory processes. Here, we review the role of complement in normal brain physiology, the events initiating complement activation after cerebral ischemia-reperfusion injury, and the contribution of complement to both injury and recovery. We also discuss how the design of future experiments may better characterize the dual role of complement in recovery after ischemic stroke.
Collapse
Affiliation(s)
- Ali Alawieh
- Neuroscience Institute, Department of Neurosciences, Medical University of South Carolina , Charleston, SC , USA
| | - Andrew Elvington
- Department of Pathology and Immunology, Washington University School of Medicine , St. Louis, MO , USA
| | - Stephen Tomlinson
- Department of Microbiology and Immunology, Ralph H. Johnson Veteran Affairs Medical Center, Medical University of South Carolina , Charleston, SC , USA
| |
Collapse
|
15
|
Imoto Y, Takabayashi T, Sakashita M, Tokunaga T, Ninomiya T, Ito Y, Narita N, Yamada T, Fujieda S. Peripheral basophil reactivity, CD203c expression by Cryj1 stimulation, is useful for diagnosing seasonal allergic rhinitis by Japanese cedar pollen. IMMUNITY INFLAMMATION AND DISEASE 2015; 3:300-8. [PMID: 26417444 PMCID: PMC4578528 DOI: 10.1002/iid3.69] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 04/08/2015] [Accepted: 05/06/2015] [Indexed: 01/03/2023]
Abstract
Measuring specific IgE can yield direct, accurate, and objective data. Nevertheless, clinical symptoms of allergy are often inconsistent with these data. Recently, the expression of CD203c, a surface marker of basophils, has been reported as capable of distinguishing allergic patients. This study compared specific IgE in serum and skin tests against antigen to assess CD203c as a biomarker correlated with allergic rhinitis (AR). We asked 3,453 subjects whether they experienced any AR related symptom. All subjects were assessed for six specific IgEs for common aeroallergens. Skin tests were also conducted for six aeroallergens. We observed the reactivity of peripheral basophil by measuring the levels of CD203c by Cryj1 stimulation using flow cytometry. Of the 3,453 participants, 1,987 (57.5%) possessed Japanese cedar pollen (JCP) specific IgE in their serum. Among those 1,987 JCP specific IgE positive participants, 552 (27.8%) had not experienced any allergic symptom during the JCP season. The levels of CD203c in the peripheral basophil by Cryj1 stimulation were significantly higher in SAR-JCP subjects than in non-SAR-JCP subjects (Cryj1 0.5 ng/ml: 2.25 ± 0.90% vs. 60.2 ± 27.4%, p < 0.01, Cryj1 50 ng/ml: 1.89 ± 0.90% vs. 68.0 ± 21.2%, p < 0.01). Our results indicate that the levels of CD203c in peripheral basophils by Cryj1 stimulation is a more objective and reliable marker that better reflects the allergic reaction by SAR-JCP in vivo than measuring specific IgE in serum or skin tests.
Collapse
Affiliation(s)
- Yoshimasa Imoto
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| | - Tetsuji Takabayashi
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| | - Masafumi Sakashita
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| | - Takahiro Tokunaga
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| | - Takahiro Ninomiya
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| | - Yumi Ito
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| | - Norihiko Narita
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| | - Takechiyo Yamada
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| | - Shigeharu Fujieda
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui Fukui, Japan
| |
Collapse
|
16
|
Coulthard LG, Woodruff TM. Is the complement activation product C3a a proinflammatory molecule? Re-evaluating the evidence and the myth. THE JOURNAL OF IMMUNOLOGY 2015; 194:3542-8. [PMID: 25848071 DOI: 10.4049/jimmunol.1403068] [Citation(s) in RCA: 188] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The complement activation product C3a is often described as a proinflammatory mediator, alongside its downstream cousin, C5a. However, emerging studies show that C3a has several anti-inflammatory facets in vivo. For example, in the acute inflammatory response, C3a acts in direct opposition to C5a, through preventing the accumulation of neutrophils in inflamed tissues by independently regulating their mobilization. This acute, protective, and opposing activity of C3a to C5a is also illustrated in models of septicemia. In this article, we reinvestigate the discovery and original classification of C3a as a proinflammatory mediator and highlight the emerging studies demonstrating anti-inflammatory effects for C3a in the immune response. It is our hope that this review illuminates these apparently contradictory roles for C3a and challenges the general dogma surrounding C3a, which, historically, has ubiquitously been described as a proinflammatory mediator. In light of this, we urge investigators to use "inflammatory modulator" as the descriptor for C3a.
Collapse
Affiliation(s)
- Liam G Coulthard
- School of Biomedical Sciences, University of Queensland, St. Lucia 4072, Queensland, Australia
| | - Trent M Woodruff
- School of Biomedical Sciences, University of Queensland, St. Lucia 4072, Queensland, Australia
| |
Collapse
|
17
|
Shao Z, Nishimura T, Leung LLK, Morser J. Carboxypeptidase B2 deficiency reveals opposite effects of complement C3a and C5a in a murine polymicrobial sepsis model. J Thromb Haemost 2015; 13:1090-102. [PMID: 25851247 PMCID: PMC4452409 DOI: 10.1111/jth.12956] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 03/18/2015] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND OBJECTIVES Carboxypeptidase B2 (CPB2) is a basic carboxypeptidase with fibrin and complement C3a and C5a as physiological substrates. We hypothesized that in polymicrobial sepsis, CPB2-deficient mice would have sustained C5a activity, leading to disease exacerbation. METHODS Polymicrobial sepsis was induced by cecal ligation and puncture (CLP). RESULTS Contrary to our hypothesis, Cpb2(-/-) mice had significantly improved survival, with reduced lung edema, less liver and kidney damage, and less disseminated intravascular coagulation. Hepatic pro-CPB2 was induced by CLP, leading to increased pro-CPB2 levels. Thrombomodulin present on mesothelium supported thrombin activation of pro-CPB2. Both wild-type and Cpb2(-/-) animals treated with a C5a receptor antagonist had improved survival, demonstrating that C5a was detrimental in this model. Treatment with a fibrinolysis inhibitor, tranexamic acid, caused a decrease in survival in both genotypes; however, the Cpb2(-/-) animals retained their survival advantage. Administration of a C3a receptor antagonist exacerbated the disease in both wild-type and Cpb2(-/-) mice and eliminated the survival advantage of Cpb2(-/-) mice. C5a receptor is expressed in both peritoneal macrophages and neutrophils; in contrast, C3a receptor expression is restricted to peritoneal macrophages, and C3a induced signaling in macrophages but not neutrophils. CONCLUSIONS While C5a exacerbates the peritonitis, resulting in a deleterious generalized inflammatory state, C3a activation of peritoneal macrophages may limit the initial infection following CLP, thereby playing a diametrically opposing protective role in this polymicrobial sepsis model.
Collapse
Affiliation(s)
- Z. Shao
- Stanford University School of Medicine, Division of Hematology, Department of Medicine, Stanford, CA 94305, USA and Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, USA
| | - T. Nishimura
- Stanford University School of Medicine, Department of Anesthesiology, Stanford, CA 94305, USA
| | - L. L. K. Leung
- Stanford University School of Medicine, Division of Hematology, Department of Medicine, Stanford, CA 94305, USA and Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, USA
| | - J. Morser
- Stanford University School of Medicine, Division of Hematology, Department of Medicine, Stanford, CA 94305, USA and Veterans Affairs Palo Alto Health Care System, Palo Alto, CA 94304, USA
| |
Collapse
|
18
|
Shinjyo N, de Pablo Y, Pekny M, Pekna M. Complement Peptide C3a Promotes Astrocyte Survival in Response to Ischemic Stress. Mol Neurobiol 2015; 53:3076-3087. [DOI: 10.1007/s12035-015-9204-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 04/29/2015] [Indexed: 01/04/2023]
|
19
|
Stahel PF, Barnum SR. The role of the complement system in CNS inflammatory diseases. Expert Rev Clin Immunol 2014; 2:445-56. [DOI: 10.1586/1744666x.2.3.445] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
20
|
Järlestedt K, Rousset CI, Ståhlberg A, Sourkova H, Atkins AL, Thornton C, Barnum SR, Wetsel RA, Dragunow M, Pekny M, Mallard C, Hagberg H, Pekna M. Receptor for complement peptide C3a: a therapeutic target for neonatal hypoxic‐ischemic brain injury. FASEB J 2013; 27:3797-804. [DOI: 10.1096/fj.13-230011] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
| | | | - Anders Ståhlberg
- Center for Brain Repair and RehabilitationDepartment of Clinical Neuroscience and RehabilitationInstitute of Neuroscience and PhysiologySahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Hana Sourkova
- Center for Brain Repair and RehabilitationDepartment of Clinical Neuroscience and RehabilitationInstitute of Neuroscience and PhysiologySahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Alison L. Atkins
- Center for Brain Repair and RehabilitationDepartment of Clinical Neuroscience and RehabilitationInstitute of Neuroscience and PhysiologySahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | | | - Scott R. Barnum
- Department of MicrobiologyUniversity of AlabamaBirminghamAlabamaUSA
| | - Rick A. Wetsel
- Research Center for Immunology and Autoimmune DiseasesInstitute of Molecular Medicine for the Prevention of Human DiseasesUniversity of Texas‐HoustonHoustonTexasUSA
| | - Mike Dragunow
- Department of PharmacologyFaculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand
- The National Research Centre for Growth and DevelopmentFaculty of Medical and Health SciencesThe University of AucklandAucklandNew Zealand
| | - Milos Pekny
- Center for Brain Repair and RehabilitationDepartment of Clinical Neuroscience and RehabilitationInstitute of Neuroscience and PhysiologySahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Carina Mallard
- Perinatal CenterSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| | - Henrik Hagberg
- Perinatal CenterSahlgrenska AcademyUniversity of GothenburgGothenburgSweden
- Department of Obstetrics and GynecologySahlgrenska AcademyUniversity of GothenburgGothenburgSweden
- Centre for the Developing BrainKing's CollegeLondonUK
| | - Marcela Pekna
- Center for Brain Repair and RehabilitationDepartment of Clinical Neuroscience and RehabilitationInstitute of Neuroscience and PhysiologySahlgrenska AcademyUniversity of GothenburgGothenburgSweden
| |
Collapse
|
21
|
Abstract
Despite significant research on the role of inflammation and immunosurveillance in the immunologic microenvironment of tumors, little attention has been given to the oncogenic capabilities of the complement cascade. The recent finding that complement may contribute to tumor growth suggests an insidious relationship between complement and cancer, especially in light of evidence that complement facilitates cellular proliferation and regeneration. We address the hypothesis that complement proteins promote carcinogenesis and suggest mechanisms by which complement can drive the fundamental features of cancer. Evidence shows that this diverse family of innate immune proteins facilitates dysregulation of mitogenic signaling pathways, sustained cellular proliferation, angiogenesis, insensitivity to apoptosis, invasion and migration, and escape from immunosurveillance. Given that the traditionally held functions for the complement system include innate immunity and cancer defense, our review suggests a new way of thinking about the role of complement proteins in neoplasia.
Collapse
Affiliation(s)
- Martin J Rutkowski
- Department of Neurological Surgery, University of California at San Francisco, 505 Parnassus Avenue, San Francisco, CA 94143, USA
| | | | | | | | | |
Collapse
|
22
|
CNS-specific expression of C3a and C5a exacerbate demyelination severity in the cuprizone model. Mol Immunol 2010; 48:219-30. [PMID: 20813409 DOI: 10.1016/j.molimm.2010.08.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Revised: 08/03/2010] [Accepted: 08/10/2010] [Indexed: 12/18/2022]
Abstract
Demyelination in the central nervous system (CNS) is known to involve several immune effector mechanisms, including complement proteins. Local production of complement by glial cells in the brain can be both harmful and protective. To investigate the roles of C3a and C5a in demyelination and remyelination pathology we utilized the cuprizone model. Transgenic mice expressing C3a or C5a under the control of the glial fibrillary acidic protein (GFAP) promoter had exacerbated demyelination and slightly delayed remyelination in the corpus callosum compared to WT mice. C3a and C5a transgenic mice had increased cellularity in the corpus callosum due to increase activation and/or migration of microglia. Oligodendrocytes migrated to the corpus callosum in higher numbers during early remyelination events in C3a and C5a transgenic mice, thus enabling these mice to remyelinate as effectively as WT mice by the end of the 10 week study. To determine the effects of C3a and/or C5a on individual glial subsets, we created murine recombinant C3a and C5a proteins. When microglia and mixed glial cultures were stimulated with C3a and/or C5a, we observed an increase in the production of proinflammatory cytokines and chemokines. In contrast, astrocytes had decreased cytokine and chemokine production in the presence of C3a and/or C5a. We also found that the MAPK pathway proteins JNK and ERK1/2 were activated in glia upon stimulation with C3a and C5a. Overall, our findings show that although C3a and C5a production in the brain play a negative role during demyelination, these proteins may aid in remyelination.
Collapse
|
23
|
Scully CCG, Blakeney JS, Singh R, Hoang HN, Abbenante G, Reid RC, Fairlie DP. Selective Hexapeptide Agonists and Antagonists for Human Complement C3a Receptor. J Med Chem 2010; 53:4938-48. [DOI: 10.1021/jm1003705] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Conor C. G. Scully
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Jade S. Blakeney
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Ranee Singh
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Huy N. Hoang
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Giovanni Abbenante
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Robert C. Reid
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - David P. Fairlie
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
| |
Collapse
|
24
|
Pendyala G, Fox HS. Proteomic and metabolomic strategies to investigate HIV-associated neurocognitive disorders. Genome Med 2010; 2:22. [PMID: 20353544 PMCID: PMC2873800 DOI: 10.1186/gm143] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Diagnosing neurodegenerative diseases, monitoring their progression and assessing responses to treatments will all be aided by the identification of molecular markers of different stages of pathology. Protein biomarkers for HIV-associated neurocognitive disorders that have been discovered using proteomics include complement C3, soluble superoxide dismutase and a prostaglandin synthase. Metabolomics has not yet been widely used for biomarker discovery, but early work shows that it has great potential.
Collapse
Affiliation(s)
- Gurudutt Pendyala
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, 985800 Nebraska Medical Center, Omaha, NE 68198, USA.
| | | |
Collapse
|
25
|
Complement in neuroprotection and neurodegeneration. Trends Mol Med 2010; 16:69-76. [PMID: 20116331 DOI: 10.1016/j.molmed.2009.12.001] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2009] [Revised: 12/21/2009] [Accepted: 12/21/2009] [Indexed: 01/10/2023]
Abstract
Acute neurodegeneration is associated with high morbidity and mortality, and there are few effective treatments. Inflammation is central to the process of neuronal death, yet the roles of the complement cascade in this process have proven to be complex and hard to unravel. The complement cascade is involved in triggering cell death and recruiting cells of the immune system to sites of inflammation, including the brain. However, complement might also have important neuroprotective roles that are only now coming to light. Recent evidence suggests that targeted activation of complement might be a potential approach for treatment of stroke and other acute neurodegenerative diseases. Here, we review these novel neuroprotective roles of the complement cascade, focusing on signaling pathways that might provide new therapeutic targets in acute neuronal injury.
Collapse
|
26
|
Ali H. Regulation of human mast cell and basophil function by anaphylatoxins C3a and C5a. Immunol Lett 2009; 128:36-45. [PMID: 19895849 DOI: 10.1016/j.imlet.2009.10.007] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Revised: 10/21/2009] [Accepted: 10/23/2009] [Indexed: 12/18/2022]
Abstract
Allergic diseases such as asthma result from inappropriate immunologic responses to common environmental allergens in genetically susceptible individuals. Following allergen exposure, interaction of dendritic cells (DC) with CD4(+) T cells leads to the production of Th2 cytokines, which induce B cells to synthesize IgE molecules (sensitization phase). These IgE molecules bind to their high affinity receptors (FcvarepsilonRI) on the surface of mast cells and basophils and their subsequent cross-linking by allergen results in the release of preformed and newly synthesized mediators, which cause bronchoconstriction, lung inflammation and airway hyperresponsiveness (AHR) in asthma (effector phase). The complement components C3a and C5a levels are increased in the lungs of patients with asthma and are likely generated via the actions of both allergen and mast cell proteases. In vivo studies with rodents have shown that while C3a facilitates allergen sensitization in some models C5a inhibits this response. Despite this difference, both anaphylatoxins promote lung inflammation and AHR in vivo indicating that cells other than DC and T cells likely mediate the functional effects of C3a and C5a in asthma. This review focuses on the contribution of C3a and C5a in the pathogenesis of asthma with a particular emphasis on mast cells and basophils. It discusses the mechanisms by which anaphylatoxins activate mast cells and basophils and the associated signaling pathways via which their receptors are regulated by priming and desensitization.
Collapse
Affiliation(s)
- Hydar Ali
- Department of Pathology, University of Pennsylvania School of Dental Medicine, 240 South 40th Street, Philadelphia, PA 19104-6030, USA.
| |
Collapse
|
27
|
Shinjyo N, Ståhlberg A, Dragunow M, Pekny M, Pekna M. Complement-Derived Anaphylatoxin C3a Regulates In Vitro Differentiation and Migration of Neural Progenitor Cells. Stem Cells 2009; 27:2824-32. [DOI: 10.1002/stem.225] [Citation(s) in RCA: 127] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
28
|
Pendyala G, Trauger SA, Kalisiak E, Ellis RJ, Siuzdak G, Fox HS. Cerebrospinal fluid proteomics reveals potential pathogenic changes in the brains of SIV-infected monkeys. J Proteome Res 2009; 8:2253-60. [PMID: 19281240 DOI: 10.1021/pr800854t] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The HIV-1-associated neurocognitive disorder occurs in approximately one-third of infected individuals. It has persisted in the current era of antiretroviral therapy, and its study is complicated by the lack of biomarkers for this condition. Since the cerebrospinal fluid is the most proximal biofluid to the site of pathology, we studied the cerebrospinal fluid in a nonhuman primate model for HIV-1-associated neurocognitive disorder. Here we present a simple and efficient liquid chromatography-coupled mass spectrometry-based proteomics approach that utilizes small amounts of cerebrospinal fluid. First, we demonstrate the validity of the methodology using human cerebrospinal fluid. Next, using the simian immunodeficiency virus-infected monkey model, we show its efficacy in identifying proteins such as alpha-1-antitrypsin, complement C3, hemopexin, IgM heavy chain, and plasminogen, whose increased expression is linked to disease. Finally, we find that the increase in cerebrospinal fluid proteins is linked to increased expression of their genes in the brain parenchyma, revealing that the cerebrospinal fluid alterations identified reflect changes in the brain itself and not merely leakage of the blood-brain or blood-cerebrospinal fluid barriers. This study reveals new central nervous system alterations in lentivirus-induced neurological disease, and this technique can be applied to other systems in which limited amounts of biofluids can be obtained.
Collapse
Affiliation(s)
- Gurudutt Pendyala
- Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, Nebraska 68198-5800, USA
| | | | | | | | | | | |
Collapse
|
29
|
Arumugam TV, Woodruff TM, Lathia JD, Selvaraj PK, Mattson MP, Taylor SM. Neuroprotection in stroke by complement inhibition and immunoglobulin therapy. Neuroscience 2009; 158:1074-89. [PMID: 18691639 PMCID: PMC2639633 DOI: 10.1016/j.neuroscience.2008.07.015] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Revised: 07/08/2008] [Accepted: 07/08/2008] [Indexed: 12/18/2022]
Abstract
Activation of the complement system occurs in a variety of neuroinflammatory diseases and neurodegenerative processes of the CNS. Studies in the last decade have demonstrated that essentially all of the activation components and receptors of the complement system are produced by astrocytes, microglia, and neurons. There is also rapidly growing evidence to indicate an active role of the complement system in cerebral ischemic injury. In addition to direct cell damage, regional cerebral ischemia and reperfusion (I/R) induces an inflammatory response involving complement activation and generation of active fragments, such as C3a and C5a anaphylatoxins, C3b, C4b, and iC3b. The use of specific inhibitors to block complement activation or their mediators such as C5a, can reduce local tissue injury after I/R. Consistent with therapeutic approaches that have been successful in models of autoimmune disorders, many of the same complement inhibition strategies are proving effective in animal models of cerebral I/R injury. One new form of therapy, which is less specific in its targeting of complement than monodrug administration, is the use of immunoglobulins. Intravenous immunoglobulin (IVIG) has the potential to inhibit multiple components of inflammation, including complement fragments, pro-inflammatory cytokine production and leukocyte cell adhesion. Thus, IVIG may directly protect neurons, reduce activation of intrinsic inflammatory cells (microglia) and inhibit transendothelial infiltration of leukocytes into the brain parenchyma following an ischemic stroke. The striking neuroprotective actions of IVIG in animal models of ischemic stroke suggest a potential therapeutic potential that merits consideration for clinical trials in stroke patients.
Collapse
Affiliation(s)
- T V Arumugam
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center, 1300 Coulter Drive, Amarillo, TX 79106, USA.
| | | | | | | | | | | |
Collapse
|
30
|
Zhou J, Fonseca MI, Pisalyaput K, Tenner AJ. Complement C3 and C4 expression in C1q sufficient and deficient mouse models of Alzheimer's disease. J Neurochem 2008; 106:2080-92. [PMID: 18624920 DOI: 10.1111/j.1471-4159.2008.05558.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease resulting in progressive cognitive decline. Amyloid plaque deposits consisting specifically of beta-amyloid peptides that have formed fibrils displaying beta-pleated sheet conformation are associated with activated microglia and astrocytes, are colocalized with C1q and other complement activation products, and appear at the time of cognitive decline in AD. Amyloid precursor protein (APP) transgenic mouse models of AD that lack the ability to activate the classical complement pathway display less neuropathology than do the APPQ+/+ mice, consistent with the hypothesis that complement activation and the resultant inflammation may play a role in the pathogenesis of AD. Further investigation of the presence of complement proteins C3 and C4 in the brain of these mice demonstrate that both C3 and C4 deposition increase with age in APPQ+/+ transgenic mice, as expected with the age-dependent increase in fibrillar beta-amyloid deposition. In addition, while C4 is predominantly localized on the plaques and/or associated with oligodendrocytes in APPQ+/+ mice, little C4 is detected in APPQ-/- brains consistent with a lack of classical complement pathway activation because of the absence of C1q in these mice. In contrast, plaque and cell associated C3 immunoreactivity is seen in both animal models and, surprisingly, is higher in APPQ-/- than in APPQ+/+ mice, providing evidence for alternative pathway activation. The unexpected increase in C3 levels in the APPQ-/- mice coincident with decreased neuropathology provides support for the hypothesis that complement can mediate protective events as well as detrimental events in this disease. Finally, induced expression of C3 in a subset of astrocytes suggests the existence of differential activation states of these cells.
Collapse
Affiliation(s)
- Jun Zhou
- Department of Molecular Biology and Biochemistry, Institute for Brain Aging and Dementia, Center for Immunology, University of California, Irvine, California 92697-3900, USA
| | | | | | | |
Collapse
|
31
|
Terao A, Huang ZL, Wisor JP, Mochizuki T, Gerashchenko D, Urade Y, Kilduff TS. Gene expression in the rat brain during prostaglandin D2 and adenosinergically-induced sleep. J Neurochem 2008; 105:1480-98. [PMID: 18331290 DOI: 10.1111/j.1471-4159.2008.05257.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Previous studies have supported the hypothesis that macromolecular synthesis occurs in the brain during sleep as a response to prior waking activities and that prostaglandin D2 (PGD2) is an endogenous sleep substance whose effects are dependent on adenosine A2a receptor-mediated signaling. We compared gene expression in the cerebral cortex, basal forebrain, and hypothalamus during PGD2-induced and adenosinergically-induced sleep to results from our previously published study of recovery sleep (RS) after sleep deprivation (SD). Immediate early gene expression in the cortex during sleep induced by PGD2- or by the selective adenosine A2a agonist CGS21680 showed limited similarity to that observed during RS while, in the basal forebrain and hypothalamus, widespread activation of immediate early genes not seen during RS occurred. In all three brain regions, PGD2 and CGS21680 reduced the expression of arc, a transcript whose expression is elevated during SD. Using GeneChips, the majority of genes induced by either PGD2 or CGS21680 were induced by both, suggesting activation of the same pathways. However, gene expression induced in the brain after PGD2 or CGS21680 treatment was distinct from that described during RS after SD and apparently involves glial cell gene activation and signaling pathways in neural-immune interactions.
Collapse
Affiliation(s)
- Akira Terao
- Biosciences Division, SRI International, Menlo Park, California 94025, USA
| | | | | | | | | | | | | |
Collapse
|
32
|
Merchant SN, Durand ML, Adams JC. Sudden deafness: is it viral? ORL J Otorhinolaryngol Relat Spec 2008; 70:52-60; discussion 60-2. [PMID: 18235206 DOI: 10.1159/000111048] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A number of theories have been proposed to explain the etiopathogenesis of idiopathic sudden sensorineural hearing loss (ISSHL), including viral infection, vascular occlusion, breaks of labyrinthine membranes, immune-mediated mechanisms and abnormal cellular stress responses within the cochlea. In the present paper, we provide a critical review of the viral hypothesis of ISSHL. The evidence reviewed includes published reports of epidemiological and serological studies, clinical observations and results of antiviral therapy, morphological and histopathological studies, as well as results of animal experiments. The published evidence does not satisfy the majority of the Henle-Koch postulates for viral causation of an infectious disease. Possible explanations as to why these postulates remain unfulfilled are reviewed, and future studies that may provide more insight are described. We also discuss other mechanisms that have been postulated to explain ISSHL. Our review indicates that vascular occlusion, labyrinthine membrane breaks and immune-mediated mechanisms are unlikely to be common causes of ISSHL. Finally, we review our recently proposed theory that abnormal cellular stress responses within the cochlea may be responsible for ISSHL.
Collapse
Affiliation(s)
- Saumil N Merchant
- Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA.
| | | | | |
Collapse
|
33
|
Bogestål YR, Barnum SR, Smith PLP, Mattisson V, Pekny M, Pekna M. Signaling through C5aR is not involved in basal neurogenesis. J Neurosci Res 2008; 85:2892-7. [PMID: 17551982 DOI: 10.1002/jnr.21401] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The complement system, an important part of the innate immune system, provides protection against invading pathogens, in part through its proinflammatory activities. Although most complement proteins are synthesized locally in the brain and the relevant complement receptors are expressed on resident brain cells, little is known about brain-specific role(s) of the complement system. C3a and C5a, complement-derived peptides with anaphylatoxic properties, have been implicated in noninflammatory functions, such as tissue regeneration and neuroprotection. Recently, we have shown that signaling through C3a receptor (C3aR) is involved in the regulation of neurogenesis. In the present study, we assessed basal neurogenesis in mice lacking C5a receptor (C5aR(-/-)) and mice expressing C3a and C5a, respectively in the CNS under the control of glial fibrillary acidic protein (GFAP) promoter (C3a/GFAP and C5a/GFAP, respectively) and thus without the requirement for complement activation. We did not observe any difference among C5aR(-/-), C3a/GFAP and C5a/GFAP mice and their respective controls in the number of newly formed neuroblasts and newly formed neurons in the subventricular zone (SVZ) of lateral ventricles and hippocampal dentate gyrus, the two neurogenic niches in the adult brain, or the olfactory bulb, the final destination of new neurons formed in the SVZ. Our results indicate that signaling through C5aR is not involved in basal neurogenesis in adult mice and that basal neurogenesis in adult C3a/GFAP and C5a/GFAP mice is not altered.
Collapse
Affiliation(s)
- Yalda Rahpeymai Bogestål
- Department of Medical Chemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy at Göteborg University, Göteborg, Sweden
| | | | | | | | | | | |
Collapse
|
34
|
Zaidi AK, Ali H. C3a receptors signaling in mast cells. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 598:126-40. [PMID: 17892209 DOI: 10.1007/978-0-387-71767-8_10] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Asifa K Zaidi
- University of Pennsylvania School of Dental Medicine, Department of Pathology, Philadelphia, PA 19104, USA.
| | | |
Collapse
|
35
|
Liang Y, Li S, Guo Q, Zhang Y, Zhang Y, Wen C, Zou Q, Su B. Complement 3-deficient mice are not protected against MPTP-induced dopaminergic neurotoxicity. Brain Res 2007; 1178:132-40. [PMID: 17900537 DOI: 10.1016/j.brainres.2007.08.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Revised: 08/13/2007] [Accepted: 08/14/2007] [Indexed: 12/20/2022]
Abstract
Recent studies have invoked inflammation as a major contributor to the pathogenesis of Parkinson's disease (PD). Emerging evidence indicated that components of complement system may be involved in such disorder and contribute to its development. We thus observed the influence of deficiency of complement 3 (C3), the key component of complement system, on the death of dopaminergic neurons in substantia nigra pars compacta (SNpc) and the loss of dopaminergic fibers in striatum induced by acute or chronic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Immunohistochemical staining of dopaminergic neurons in SNpc and neurochemical analysis of dopamine and its metabolites in striata revealed that there was no significant difference between the two genotypes. Longer survival time also indicated that C3 might not mediate the spontaneous recovery of dopaminergic fibers in mouse striatum acutely challenged by MPTP. We conclude that, despite growing evidence indicating the involvement of complement system in the pathogenesis of PD, our data do not support a role for C3 in this established model of PD, as indicated by results from HPLC analysis and immunohistochemical staining.
Collapse
Affiliation(s)
- Yajie Liang
- Department of Neurobiology, Third Military Medical University, Chongqing 400038, PR China
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Carson MJ, Lo DD. Perspective is everything: an irreverent discussion of CNS-immune system interactions as viewed from different scientific traditions. Brain Behav Immun 2007; 21:367-73. [PMID: 17234380 PMCID: PMC2626194 DOI: 10.1016/j.bbi.2006.11.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/11/2006] [Revised: 11/13/2006] [Accepted: 11/15/2006] [Indexed: 01/27/2023] Open
Abstract
The immune system is a host defense system comprised of both innate mechanisms able to rapidly recognize and respond to conserved pathogen associated molecular patterns (PAMPs) as well as adaptive mechanisms able to respond to a wide variety of non-conserved and conserved pathogen associated molecules. In vitro and in vivo studies have demonstrated that the kinetics and type of immune response triggered by pathogenic insults is a function of both the nature of the insult and the subsequent cross-regulatory interactions between the responding immune cells. In this context, the potential immunomodulatory influences of the nervous system have been often viewed as exerting minimal modulatory effects and thus of being largely irrelevant in the development of immune responses. Here, using a Saturday Night Live (SNL)-styled point:counterpoint format, we discuss whether and to what extent the nervous system can shape the responses of the immune system. Finally, we examine whether primary degenerative disorders of the CNS are likely to lead to alterations in immune function.
Collapse
Affiliation(s)
- Monica J Carson
- Division of Biomedical Sciences, The University of California, Riverside, CA 92521-0121, USA.
| | | |
Collapse
|
37
|
Griffiths M, Neal JW, Gasque P. Innate immunity and protective neuroinflammation: new emphasis on the role of neuroimmune regulatory proteins. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2007; 82:29-55. [PMID: 17678954 DOI: 10.1016/s0074-7742(07)82002-2] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Brain inflammation due to infection, hemorrhage, and aging is associated with activation of the local innate immune system as expressed by infiltrating cells, resident glial cells, and neurons. The innate immune response relies on the detection of "nonself" and "danger-self" ligands behaving as "eat me signals" by a plethora of pattern recognition receptors (PRRs) expressed by professional and amateur phagocytes to promote the clearance of pathogens, toxic cell debris (amyloid fibrils, aggregated synucleins, prions), and apoptotic cells accumulating within the brain parenchyma and the cerebrospinal fluid (CSF). These PRRs (e.g., complement, TLR, CD14, scavenger receptors) are highly conserved between vertebrates and invertebrates and may represent the most ancestral innate scavenging system involved in tissue homeostasis. However, in some diseases, these protective mechanisms lead to neurodegeneration on the ground that several innate immune molecules have neurocytotoxic activities. The response is a "double-edged sword" representing a fine balance between protective and detrimental effects. Several key regulatory mechanisms have now been evidenced in the control of CNS innate immunity, and these could be harnessed to explore novel therapeutic avenues. We will herein provide new emphasis on the role of neuroimmune regulatory proteins (NIRegs), such as CD95L, TNF, CD200, CD47, sialic acids, CD55, CD46, fH, C3a, HMGB1, which are involved in silencing innate immunity at the cellular and molecular levels and suppression of inflammation. For instance, NIRegs may play an important role in controlling lymphocyte/macrophage/microglia hyperinflammatory responses, while sparing host defense and repair mechanisms. Moreover, NIRegs have direct beneficial effects on neurogenesis and contributing to brain tissue remodeling.
Collapse
Affiliation(s)
- M Griffiths
- Brain Inflammation and Immunity Group (BIIG), Department of Medical Biochemistry, School of Medicine, Cardiff University, CF144XN Cardiff, United Kingdom
| | | | | |
Collapse
|
38
|
Flierl MA, Schreiber H, Huber-Lang MS. The role of complement, C5a and its receptors in sepsis and multiorgan dysfunction syndrome. J INVEST SURG 2006; 19:255-65. [PMID: 16835140 DOI: 10.1080/08941930600778263] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Sepsis continues to be a major clinical problem that is difficult to treat, as the pathophysiology of the disease is still unclear. Despite promising experimental strategies, therapeutic interventions have been largely unsuccessful. There is now increasing evidence that the disturbance of innate immunity during sepsis and multiorgan dysfunction syndrome (MODS) may be linked to uncontrolled activation of the complement system. Especially, the powerful anaphylatoxin C5a seems to play a key role in the development of immune paralysis. In this review, we describe our present understanding of the role of complement in the inflammatory response during sepsis and MODS.
Collapse
Affiliation(s)
- Michael A Flierl
- Department of Traumatology, Hand and Reconstructive Surgery, University Hospital of Ulm, Steinhoevelstrasse 9, 89075 Ulm, Germany
| | | | | |
Collapse
|
39
|
Barnum SR, Szalai AJ. Complement and demyelinating disease: no MAC needed? ACTA ACUST UNITED AC 2006; 52:58-68. [PMID: 16443278 DOI: 10.1016/j.brainresrev.2005.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2005] [Revised: 12/09/2005] [Accepted: 12/15/2005] [Indexed: 12/22/2022]
Abstract
It has long been accepted that the complement system participates in the onset, evolution, and exacerbation of demyelinating disease, and it is widely suspected that this is accomplished mainly via destruction of nervous tissue by membrane attack complex (MAC)-mediated lysis of oligodendrocytes and neurons. However, recent studies using mutant mice indicate the MAC may not be so important. For example, mice lacking C5 and mice lacking the C5a receptor both develop experimental autoimmune encephalomyelitis (EAE) with the same frequency and intensity as their wild type counterparts. Also, transgenic mice that express C5a exclusively in the central nervous system (CNS) develop EAE that is not remarkably different from that in non-transgenic littermates. Since C5 is required for formation of the MAC, development of fulminant EAE in the absence of this complement protein demonstrates that non-complement-mediated mechanisms of CNS damage are operating. Paradoxically, mice lacking C3, mice lacking the C3a receptor, and mice lacking the complement receptor type 3 develop attenuated EAE, while mice that express C3a exclusively in the CNS develop severe and often fulminant EAE. Based on these newer data, we posit that C3-derived biologically active fragments, rather than C5 and the MAC, are central players in the pathophysiology of complement in EAE.
Collapse
Affiliation(s)
- Scott R Barnum
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
| | | |
Collapse
|
40
|
Reiman R, Campos Torres A, Martin BK, Ting JP, Campbell IL, Barnum SR. Expression of C5a in the brain does not exacerbate experimental autoimmune encephalomyelitis. Neurosci Lett 2005; 390:134-8. [PMID: 16154690 DOI: 10.1016/j.neulet.2005.08.022] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2005] [Revised: 08/04/2005] [Accepted: 08/05/2005] [Indexed: 11/26/2022]
Abstract
Complement is implicated in the pathology of neurodegenerative and inflammatory disease in the central nervous system (CNS). Although studies demonstrate that inhibition of complement activation attenuates disease development in the CNS, the specific complement components that contribute to the pathogenesis of CNS diseases remain unclear. To dissect the role of C5a in CNS disease, we developed a transgenic mouse that produces C5a exclusively in the brain using the astrocyte-specific, murine glial fibrillary acidic protein (GFAP) promoter. C5a/GFAP mice develop normally and do not demonstrate any signs of spontaneous inflammation or neurodegeneration with age. Using C5a/GFAP mice, we examined the outcome of the animal model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). To our surprise the onset and severity of myelin oligodendrocyte glycoprotein-induced EAE was essentially identical between C5a/GFAP and control mice. These results demonstrate that C5a, despite it is pro-inflammatory functions, is not critical to the development and progression of EAE.
Collapse
MESH Headings
- Animals
- Brain/metabolism
- Brain/pathology
- Complement C5a/genetics
- Complement C5a/metabolism
- Disease Models, Animal
- Encephalomyelitis, Autoimmune, Experimental/chemically induced
- Encephalomyelitis, Autoimmune, Experimental/genetics
- Encephalomyelitis, Autoimmune, Experimental/metabolism
- Encephalomyelitis, Autoimmune, Experimental/physiopathology
- Fluorescent Antibody Technique/methods
- Gene Expression Regulation/physiology
- Glial Fibrillary Acidic Protein/biosynthesis
- Glycoproteins
- Humans
- Mice
- Mice, Transgenic
- Myelin-Oligodendrocyte Glycoprotein
- Peptide Fragments
- Severity of Illness Index
Collapse
Affiliation(s)
- Rachael Reiman
- Department of Microbiology, University of Alabama at Birmingham, 845 19th St. S., Birmingham, AL 35294, USA
| | | | | | | | | | | |
Collapse
|