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Lamanna J, Ferro M, Spadini S, Racchetti G, Malgaroli A. The Dysfunctional Mechanisms Throwing Tics: Structural and Functional Changes in Tourette Syndrome. Behav Sci (Basel) 2023; 13:668. [PMID: 37622808 PMCID: PMC10451670 DOI: 10.3390/bs13080668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 07/31/2023] [Accepted: 08/07/2023] [Indexed: 08/26/2023] Open
Abstract
Tourette Syndrome (TS) is a high-incidence multifactorial neuropsychiatric disorder characterized by motor and vocal tics co-occurring with several diverse comorbidities, including obsessive-compulsive disorder and attention-deficit hyperactivity disorder. The origin of TS is multifactorial, with strong genetic, perinatal, and immunological influences. Although almost all neurotransmettitorial systems have been implicated in TS pathophysiology, a comprehensive neurophysiological model explaining the dynamics of expression and inhibition of tics is still lacking. The genesis and maintenance of motor and non-motor aspects of TS are thought to arise from functional and/or structural modifications of the basal ganglia and related circuitry. This complex wiring involves several cortical and subcortical structures whose concerted activity controls the selection of the most appropriate reflexive and habitual motor, cognitive and emotional actions. Importantly, striatal circuits exhibit bidirectional forms of synaptic plasticity that differ in many respects from hippocampal and neocortical plasticity, including sensitivity to metaplastic molecules such as dopamine. Here, we review the available evidence about structural and functional anomalies in neural circuits which have been found in TS patients. Finally, considering what is known in the field of striatal plasticity, we discuss the role of exuberant plasticity in TS, including the prospect of future pharmacological and neuromodulation avenues.
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Affiliation(s)
- Jacopo Lamanna
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, 20132 Milan, Italy
- Faculty of Psychology, Vita-Salute San Raffaele University, 20132 Milan, Italy
| | - Mattia Ferro
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, 20132 Milan, Italy
- Department of Psychology, Sigmund Freud University, 20143 Milan, Italy
| | - Sara Spadini
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, 20132 Milan, Italy
- Division of Neuroscience, Scientific Institute Ospedale San Raffaele, 20132 Milan, Italy
| | - Gabriella Racchetti
- Division of Neuroscience, Scientific Institute Ospedale San Raffaele, 20132 Milan, Italy
| | - Antonio Malgaroli
- Center for Behavioral Neuroscience and Communication (BNC), Vita-Salute San Raffaele University, 20132 Milan, Italy
- Faculty of Psychology, Vita-Salute San Raffaele University, 20132 Milan, Italy
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Lamothe H, Tamouza R, Hartmann A, Mallet L. Immunity and Gilles de la Tourette syndrome: A systematic review and meta-analysis of evidence for immune implications in Tourette syndrome. Eur J Neurol 2021; 28:3187-3200. [PMID: 34133837 DOI: 10.1111/ene.14983] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 05/30/2021] [Accepted: 06/10/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND AND PURPOSE The neurobiology of Gilles de la Tourette syndrome (GTS) is known to involve corticostriatal loops possibly under genetic control. Less is known about possible environmental triggers of GTS. Specifically, immune-related events following possible environmental inducers have been evoked, but important controversies still exist. In this systematic review and meta-analysis, we looked for evidence in favor of such possibilities. METHODS We performed a systematic review and meta-analysis of all immunological data in PubMed. RESULTS We found large discrepancies concerning immune dysfunctions in GTS, and meta-analyzing cytokines data did not allow us to conclude there is an involvement of specific cytokines in GTS neurobiology. When looking specifically at pediatric autoimmune neuropsychiatric disorder associated with streptococcus/pediatric acute onset neuropsychiatric syndrome, we found some important evidence of a possible infectious involvement but in a limited number of studies. Our meta-analysis found an increased level of anti-streptolysin O antibodies in GTS patients, but the level of anti-DNase B antibodies was not increased. CONCLUSIONS Too many questions still exist to allow us to definitively reach the conclusion that there is an infectious and immunological etiology in GTS. Much work is still needed to elucidate the possible role of immunology in GTS neurobiology and to favor immunological treatment rather than classical treatment.
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Affiliation(s)
- Hugues Lamothe
- Assistance Publique-Hôpitaux de Paris, Pôle de Psychiatrie, Hôpitaux Universitaires Henri Mondor-Albert Chenevier, Paris-East Créteil University, Créteil, France.,Institut du Cerveau et de la Moelle Épinière, INSERM U1127, CNRS UMR 7225, Sorbonne University, Paris, France
| | - Ryad Tamouza
- Assistance Publique-Hôpitaux de Paris, Pôle de Psychiatrie, Hôpitaux Universitaires Henri Mondor-Albert Chenevier, Paris-East Créteil University, Créteil, France.,Institut Mondor de Recherche Biomédical, Paris-East Créteil University, Team "Psychiatrie Translationnelle, INSERM U955, Créteil, France
| | - Andreas Hartmann
- Institut du Cerveau et de la Moelle Épinière, INSERM U1127, CNRS UMR 7225, Sorbonne University, Paris, France.,Centre Hospitalo-Universitaire de la Pitié Salpétrière, Paris, France
| | - Luc Mallet
- Assistance Publique-Hôpitaux de Paris, Pôle de Psychiatrie, Hôpitaux Universitaires Henri Mondor-Albert Chenevier, Paris-East Créteil University, Créteil, France.,Institut du Cerveau et de la Moelle Épinière, INSERM U1127, CNRS UMR 7225, Sorbonne University, Paris, France.,Department of Mental Health and Psychiatry, Global Health Institute, University of Geneva, Geneva, Switzerland
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Hsu CJ, Wong LC, Lee WT. Immunological Dysfunction in Tourette Syndrome and Related Disorders. Int J Mol Sci 2021; 22:ijms22020853. [PMID: 33467014 PMCID: PMC7839977 DOI: 10.3390/ijms22020853] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 01/09/2021] [Accepted: 01/11/2021] [Indexed: 12/28/2022] Open
Abstract
Chronic tic disorder and Tourette syndrome are common childhood-onset neurological diseases. However, the pathophysiology underlying these disorders is unclear, and most studies have focused on the disinhibition of the corticostriatal–thalamocortical circuit. An autoimmune dysfunction has been proposed in the pathogenetic mechanism of Tourette syndrome and related neuropsychiatric disorders such as obsessive–compulsive disorder, autism, and attention-deficit/hyperactivity disorder. This is based on evidence from animal model studies and clinical findings. Herein, we review and give an update on the clinical characteristics, clinical evidence, and genetic studies in vitro as well as animal studies regarding immune dysfunction in Tourette syndrome.
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Affiliation(s)
- Chia-Jui Hsu
- Department of Pediatrics, National Taiwan University Hospital Hsin-Chu Branch, Hsinchu 300, Taiwan;
| | - Lee-Chin Wong
- Department of Pediatrics, Cathay General Hospital, Taipei 106, Taiwan;
- Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei 100, Taiwan
| | - Wang-Tso Lee
- Department of Pediatric Neurology, National Taiwan University Children’s Hospital, Taipei 100, Taiwan
- Department of Pediatrics, National Taiwan University College of Medicine, Taipei 100, Taiwan
- Graduate Institute of Brain and Mind Sciences, National Taiwan University College of Medicine, Taipei 100, Taiwan
- Correspondence: ; Tel.: +886-2-2312-3456 (ext. 71545); Fax: +886-2-2314-7450
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Martino D, Johnson I, Leckman JF. What Does Immunology Have to Do With Normal Brain Development and the Pathophysiology Underlying Tourette Syndrome and Related Neuropsychiatric Disorders? Front Neurol 2020; 11:567407. [PMID: 33041996 PMCID: PMC7525089 DOI: 10.3389/fneur.2020.567407] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 08/20/2020] [Indexed: 12/20/2022] Open
Abstract
Objective: The goal of this article is to review the past decade's literature and provide a critical commentary on the involvement of immunological mechanisms in normal brain development, as well as its role in the pathophysiology of Tourette syndrome, other Chronic tic disorders (CTD), and related neuropsychiatric disorders including Obsessive-compulsive disorder (OCD) and Attention deficit hyperactivity disorder (ADHD). Methods: We conducted a literature search using the Medline/PubMed and EMBASE electronic databases to locate relevant articles and abstracts published between 2009 and 2020, using a comprehensive list of search terms related to immune mechanisms and the diseases of interest, including both clinical and animal model studies. Results: The cellular and molecular processes that constitute our "immune system" are crucial to normal brain development and the formation and maintenance of neural circuits. It is also increasingly evident that innate and adaptive systemic immune pathways, as well as neuroinflammatory mechanisms, play an important role in the pathobiology of at least a subset of individuals with Tourette syndrome and related neuropsychiatric disorders In the conceptual framework of the holobiont theory, emerging evidence points also to the importance of the "microbiota-gut-brain axis" in the pathobiology of these neurodevelopmental disorders. Conclusions: Neural development is an enormously complex and dynamic process. Immunological pathways are implicated in several early neurodevelopmental processes including the formation and refinement of neural circuits. Hyper-reactivity of systemic immune pathways and neuroinflammation may contribute to the natural fluctuations of the core behavioral features of CTD, OCD, and ADHD. There is still limited knowledge of the efficacy of direct and indirect (i.e., through environmental modifications) immune-modulatory interventions in the treatment of these disorders. Future research also needs to focus on the key molecular pathways through which dysbiosis of different tissue microbiota influence neuroimmune interactions in these disorders, and how microbiota modification could modify their natural history. It is also possible that valid biomarkers will emerge that will guide a more personalized approach to the treatment of these disorders.
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Affiliation(s)
- Davide Martino
- Department of Clinical Neurosciences & Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
| | - Isaac Johnson
- Child Study Center, Yale University, New Haven, CT, United States
- Department of Psychiatry, University of California, San Francisco, San Francisco, CA, United States
| | - James F. Leckman
- Child Study Center, Yale University, New Haven, CT, United States
- Departments of Psychiatry, Pediatrics and Psychology, Yale University, New Haven, CT, United States
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Baglioni V, Coutinho E, Menassa DA, Giannoccaro MP, Jacobson L, Buttiglione M, Petruzzelli O, Cardona F, Vincent A. Antibodies to neuronal surface proteins in Tourette Syndrome: Lack of evidence in a European paediatric cohort. Brain Behav Immun 2019; 81:665-669. [PMID: 31425826 DOI: 10.1016/j.bbi.2019.08.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 08/12/2019] [Accepted: 08/14/2019] [Indexed: 10/26/2022] Open
Abstract
In Tourette Syndrome (TS) a role for autoantibodies directed against neuronal proteins has long been suspected, but so far results are still inconsistent. The aim of this study was to look for antibodies to specific or undefined neuronal proteins that could be involved in the aetiology of the disease. Sera from children with Tourette Syndrome or another chronic tic disorder (TS/TD), collected as part of the longitudinal European Multicenter Tics in Children Study, were investigated. Participants included 30 siblings of patients with TS/TD prior to developing tics (preclinical stage) and the same children after the first tic onset (onset), and 158 patients in the chronic phase undergoing an acute relapse (exacerbation). Presence of antibodies binding to rodent brain tissue was assessed by immunohistology on rat brain sections and by immunofluorescent staining of live hippocampal neurons. Live cell-based assays were used to screen for antibodies to NMDAR, CASPR2, LGI1, AMPAR and GABAAR. Immunohistology indicated evidence of antibodies reactive with brain tissue, binding mainly to the hippocampus, the basal ganglia or the cerebellum in 26/218 (12%), with 8% of the preclinical or onset sera binding to the dentate gyrus/CA3 region or cerebellum. Only two individuals (one pre-clinical, one chronic) had antibodies binding the NMDAR and the binding was only weakly positive. No other specific antibodies were detected. Despite some immunoreactivity towards neuronal antigens on brain tissue, this was not mirrored by antibodies binding to live neurons, suggesting the presence of non-specific antibodies or those that bind non-pathogenic intracellular epitopes. NMDAR or the other neuronal surface antibodies tested were very infrequent in these patients. The evidence for pathogenic antibodies that could be causative of TS is weak.
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Affiliation(s)
- V Baglioni
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK; Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - E Coutinho
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - D A Menassa
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - M P Giannoccaro
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - L Jacobson
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
| | - M Buttiglione
- Department of Biomedical Sciences and Human Oncology, University of Bari, Bari, Italy
| | - O Petruzzelli
- Department of Biomedical Sciences and Human Oncology, University of Bari, Bari, Italy
| | - F Cardona
- Department of Human Neurosciences, Sapienza University of Rome, 00185 Rome, Italy
| | - A Vincent
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford OX3 9DU, UK
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Spinello C, Laviola G, Macrì S. Pediatric Autoimmune Disorders Associated with Streptococcal Infections and Tourette's Syndrome in Preclinical Studies. Front Neurosci 2016; 10:310. [PMID: 27445678 PMCID: PMC4928151 DOI: 10.3389/fnins.2016.00310] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 06/20/2016] [Indexed: 01/08/2023] Open
Abstract
Accumulating evidence suggests that Tourette's Syndrome (TS) - a multifactorial pediatric disorder characterized by the recurrent exhibition of motor tics and/or vocal utterances - can partly depend on immune dysregulation provoked by early repeated streptococcal infections. The natural and adaptive antibody-mediated reaction to streptococcus has been proposed to potentially turn into a pathological autoimmune response in vulnerable individuals. Specifically, in conditions of increased permeability of the blood brain barrier (BBB), streptococcus-induced antibodies have been proposed to: (i) reach neuronal targets located in brain areas responsible for motion control; and (ii) contribute to the exhibition of symptoms. This theoretical framework is supported by indirect evidence indicating that a subset of TS patients exhibit elevated streptococcal antibody titers upon tic relapses. A systematic evaluation of this hypothesis entails preclinical studies providing a proof of concept of the aforementioned pathological sequelae. These studies shall rest upon individuals characterized by a vulnerable immune system, repeatedly exposed to streptococcus, and carefully screened for phenotypes isomorphic to the pathological signs of TS observed in patients. Preclinical animal models may thus constitute an informative, useful tool upon which conducting targeted, hypothesis-driven experiments. In the present review we discuss the available evidence in preclinical models in support of the link between TS and pediatric autoimmune neuropsychiatric disorders associated with streptococcus infections (PANDAS), and the existing gaps that future research shall bridge. Specifically, we report recent preclinical evidence indicating that the immune responses to repeated streptococcal immunizations relate to the occurrence of behavioral and neurological phenotypes reminiscent of TS. By the same token, we discuss the limitations of these studies: limited evidence of behavioral phenotypes isomorphic to tics and scarce knowledge about the immunological phenomena favoring the transition from natural adaptive immunity to pathological outcomes.
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Affiliation(s)
- Chiara Spinello
- Section of Behavioural Neuroscience, Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Roma, Italy
| | - Giovanni Laviola
- Section of Behavioural Neuroscience, Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Roma, Italy
| | - Simone Macrì
- Section of Behavioural Neuroscience, Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità Roma, Italy
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Dalsgaard S, Waltoft BL, Leckman JF, Mortensen PB. Maternal history of autoimmune disease and later development of tourette syndrome in offspring. J Am Acad Child Adolesc Psychiatry 2015; 54:495-501.e1. [PMID: 26004665 DOI: 10.1016/j.jaac.2015.03.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 02/26/2015] [Accepted: 03/13/2015] [Indexed: 12/20/2022]
Abstract
OBJECTIVE In a nationwide prospective cohort study, we examined the possible association between maternal autoimmune disease (AD) and later diagnosis of Tourette syndrome (TS) in offspring. METHOD Data from national Danish health registers identified a cohort consisting of all children born in Denmark between 1990 and 2007 (n = 1,116,255), followed prospectively from birth until 2011, date of TS diagnosis, death, or emigration/disappearance, whichever came first. The incidence rate ratio (IRR) of TS, dependent on whether or not the mother had a prior diagnosis of AD, was estimated by Poisson regression with 95% CIs and adjusted for age, calendar time, place of birth, maternal and paternal age, parental psychiatric diagnoses other than TS, and parental TS. RESULTS The cohort contributed a total of 13,000,162 person years and 2,442 participants with a diagnosis of TS (414 females and 2,028 males). Prior maternal AD was found in 110 of the 2,442 children with TS, corresponding to an increased risk of TS, with an adjusted IRR of 1.22 (95% CI = 1.01-1.48). Maternal history of a prior AD increased the risk of TS in males, with an adjusted IRR of 1.29 (95% CI = 1.05-1.58), but not in females, with an adjusted IRR of 0.89 (95% CI = 0.52-1.52). CONCLUSION Maternal AD was associated with a 29% increased incidence rate of TS in male offspring. This finding supports the hypothesis that neuroimmunological disorders may act as a component in the etiology of a subset of TS.
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Affiliation(s)
- Søren Dalsgaard
- National Centre for Register-Based Research (NCRR), Aarhus University, Aarhus, Denmark, and the Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, Aarhus and Copenhagen, Denmark; Hospital of Telemark, Kragerø, Norway.
| | - Berit L Waltoft
- National Centre for Register-Based Research (NCRR), Aarhus University, Aarhus, Denmark, and the Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH, Aarhus and Copenhagen, Denmark; Bioinformatics Research Centre, Aarhus University
| | - James F Leckman
- Child Study Center, Yale University School of Medicine, New Haven, CT
| | - Preben Bo Mortensen
- NCRR, School of Business and Social Sciences, Aarhus University, and the Lundbeck Foundation Initiative for Integrative Psychiatric Research, iPSYCH
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Godar SC, Mosher LJ, Di Giovanni G, Bortolato M. Animal models of tic disorders: a translational perspective. J Neurosci Methods 2014; 238:54-69. [PMID: 25244952 DOI: 10.1016/j.jneumeth.2014.09.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 09/09/2014] [Accepted: 09/11/2014] [Indexed: 12/30/2022]
Abstract
Tics are repetitive, sudden movements and/or vocalizations, typically enacted as maladaptive responses to intrusive premonitory urges. The most severe tic disorder, Tourette syndrome (TS), is a childhood-onset condition featuring multiple motor and at least one phonic tic for a duration longer than 1 year. The pharmacological treatment of TS is mainly based on antipsychotic agents; while these drugs are often effective in reducing tic severity and frequency, their therapeutic compliance is limited by serious motor and cognitive side effects. The identification of novel therapeutic targets and development of better treatments for tic disorders is conditional on the development of animal models with high translational validity. In addition, these experimental tools can prove extremely useful to test hypotheses on the etiology and neurobiological bases of TS and related conditions. In recent years, the translational value of these animal models has been enhanced, thanks to a significant re-organization of our conceptual framework of neuropsychiatric disorders, with a greater focus on endophenotypes and quantitative indices, rather than qualitative descriptors. Given the complex and multifactorial nature of TS and other tic disorders, the selection of animal models that can appropriately capture specific symptomatic aspects of these conditions can pose significant theoretical and methodological challenges. In this article, we will review the state of the art on the available animal models of tic disorders, based on genetic mutations, environmental interventions as well as pharmacological manipulations. Furthermore, we will outline emerging lines of translational research showing how some of these experimental preparations have led to significant progress in the identification of novel therapeutic targets for tic disorders.
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Affiliation(s)
- Sean C Godar
- Department of Pharmacology and Toxicology, School of Pharmacy; University of Kansas, Lawrence, KS, USA
| | - Laura J Mosher
- Department of Pharmacology and Toxicology, School of Pharmacy; University of Kansas, Lawrence, KS, USA
| | - Giuseppe Di Giovanni
- Department of Physiology and Biochemistry, University of Malta, Msida, Malta; School of Biosciences, Cardiff University, Cardiff, UK
| | - Marco Bortolato
- Department of Pharmacology and Toxicology, School of Pharmacy; University of Kansas, Lawrence, KS, USA; Consortium for Translational Research on Aggression and Drug Abuse (ConTRADA), University of Kansas, Lawrence, KS, USA.
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Martino D, Zis P, Buttiglione M. The role of immune mechanisms in Tourette syndrome. Brain Res 2014; 1617:126-43. [PMID: 24845720 DOI: 10.1016/j.brainres.2014.04.027] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 04/18/2014] [Accepted: 04/19/2014] [Indexed: 01/11/2023]
Abstract
Tourette syndrome (TS) is a childhood-onset tic disorder associated with abnormal development of brain networks involved in the sensory and motor processing. An involvement of immune mechanisms in its pathophysiology has been proposed. Animal models based on active immunization with bacterial or viral mimics, direct injection of cytokines or patients' serum anti-neuronal antibodies, and transgenic approaches replicated stereotyped behaviors observed in human TS. A crucial role of microglia in the neural-immune crosstalk within TS and related disorders has been proposed by animal models and confirmed by recent post mortem studies. With analogy to autism, genetic and early life environmental factors could foster the involvement of immune mechanisms to the abnormal developmental trajectories postulated in TS, as well as lead to systemic immune dysregulation in this condition. Clinical studies demonstrate an association between TS and immune responses to pathogens like group A Streptococcus (GAS), although their role as risk-modifiers is still undefined. Overactivity of immune responses at a systemic level is suggested by clinical studies exploring cytokine and immunoglobulin levels, immune cell subpopulations, and gene expression profiling of peripheral lymphocytes. The involvement of autoantibodies, on the other hand, remains uncertain and warrants more work using live cell-based approaches. Overall, a body of evidence supports the hypothesis that disease mechanisms in TS, like other neurodevelopmental illnesses (e.g. autism), may involve dysfunctional neural-immune cross-talk, ultimately leading to altered maturation of brain pathways controlling different behavioral domains and, possibly, differences in organising immune and stress responses. This article is part of a Special Issue entitled SI: Neuroimmunology in Health And Disease.
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Affiliation(s)
- Davide Martino
- Neurology Department, King's College Hospital, London, UK; Queen Elizabeth Hospital, Woolwich, London, UK; Centre for Neuroscience and Trauma, Queen Mary University of London, London, UK.
| | - Panagiotis Zis
- Neurology Department, King's College Hospital, London, UK
| | - Maura Buttiglione
- Department of Biomedical Sciences and Human Oncology, University of Bari, Bari, Italy
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Immune-mediated animal models of Tourette syndrome. Neurosci Biobehav Rev 2013; 37:1120-38. [PMID: 23313649 DOI: 10.1016/j.neubiorev.2013.01.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Revised: 12/11/2012] [Accepted: 01/03/2013] [Indexed: 12/20/2022]
Abstract
An autoimmune diathesis has been proposed in Tourette syndrome (TS) and related neuropsychiatric disorders such as obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism and anorexia nervosa. Environmental triggers including infection and xenobiotics are hypothesized to lead to the production of brain-directed autoantibodies in a subset of genetically susceptible individuals. Although much work has focused on Group A Streptococcus (GAS), the role of this common childhood infection remains controversial. Animal model studies based on immune and autoantibody findings in TS have demonstrated immunoglobulin (Ig) deposits and stereotypic movements and related behavioral disturbances reminiscent of TS following exposure to GAS, other activators of host anti-microbial responses, soluble immune mediators and anti-GAS or anti-neuronal antibodies. Demonstration of the ability to recreate these abnormalities through passive transfer of serum IgG from GAS-immunized mice into naïve mice and abrogation of this activity through depletion of IgG has provided compelling evidence in support of the autoimmune hypothesis. Immunologically-based animal models of TS are a potent tool for dissecting the pathogenesis of this serious neuropsychiatric syndrome.
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