Process Of Experimental Autoimmune Encephalomyelitis Research Articles

Single-Cell Transcriptomics Identifies Brain Endothelium Inflammatory Networks in Experimental Autoimmune Encephalomyelitis.

Multiple sclerosis (MS) is a neuroinflammatory and neurodegenerative disease characterized by infiltration of immune cells in multifocal areas of the CNS. The specific molecular processes allowing autoreactive immune cells to enter the CNS compartment through the blood-brain barrier remain elusive. Using endothelial cell (EC) enrichment and single-cell RNA sequencing, we characterized the cells implicated in the neuroinflammatory processes in experimental autoimmune encephalomyelitis, an animal model of MS. Validations on human MS brain sections of the most differentially expressed genes in venous ECs were performed using immunohistochemistry and confocal microscopy. We found an upregulation of genes associated with antigen presentation and interferon in most populations of CNS-resident cells, including ECs. Interestingly, instead of transcriptionally distinct profiles, a continuous gradient of gene expression separated the arteriovenous zonation of the brain vasculature. However, differential gene expression analysis presented more transcriptomic alterations on the venous side of the axis, suggesting a prominent role of venous ECs in neuroinflammation. Furthermore, analysis of ligand-receptor interactions identified important potential molecular communications between venous ECs and infiltrated immune populations. To confirm the relevance of our observation in the context of human disease, we validated the protein expression of the most upregulated genes (Ackr1 and Lcn2) in MS lesions. In this study, we provide a landscape of the cellular heterogeneity associated with neuroinflammation. We also present important molecular insights for further exploration of specific cell processes that promote infiltration of immune cells inside the brain of experimental autoimmune encephalomyelitis mice.

Glyceryl tribenzoate: A food additive with unique properties to be a substitute for cinnamon.

Cinnamon is a regularly used natural seasoning and flavoring material throughout the world for eras. Recent laboratory studies have demonstrated that oral cinnamon may be beneficial for different neuroinflammatory and neurodegenerative disorders such as multiple sclerosis (MS), Parkinson's disease (PD), Alzheimer's disease (AD), and Lewy body diseases (LBD). However, cinnamon's certain limitations (e.g. unavailability of true Ceylon cinnamon throughout the world, impurities in ground cinnamon, etc.) have initiated an interest among researchers to find an alternate of cinnamon that can potentially deliver the same efficacy in the diseases mentioned above. Glyceryl tribenzoate (GTB) is a U.S. Food and Drug Administration (FDA)-approved flavoring ingredient that is used in food and food packaging industries. It has been found that similar to cinnamon, oral GTB is capable of upregulating regulatory T cells and suppressing the autoimmune disease process of experimental autoimmune encephalomyelitis, an animal model of MS. Moreover, both GTB and cinnamon metabolite sodium benzoate (NaB) have the potency to attenuate neurodegenerative pathology in a mouse model of Huntington disease (HD). Here, we have also demonstrated anti-inflammatory property of GTB in astrocytes and macrophages, a property that is also seen with cinnamon and its metabolite sodium benzoate (NaB). Therefore, here, we have made a sincere attempt to discuss the similarities and dissimilarities between cinnamon and GTB with a focus whether GTB has the potential to be considered as a substitute of cinnamon for neuroinflammatory and neurodegenerative disorders.

IL-12 p40 monomer is different from other IL-12 family members to selectively inhibit IL-12Rβ1 internalization and suppress EAE

Multiple sclerosis (MS) is the most common human demyelinating disease of the central nervous system. The IL-12 family of cytokines has four members, which are IL-12 (p40:p35), IL-23 (p40:p19), the p40 monomer (p40), and the p40 homodimer (p402). Since all four members contain p40 in different forms, it is important to use a specific monoclonal antibody (mAb) to characterize these molecules. Here, by using such mAbs, we describe selective loss of p40 in serum of MS patients as compared to healthy controls. Similarly, we also observed decrease in p40 and increase in IL-12, IL-23, and p402 in serum of mice with experimental autoimmune encephalomyelitis (EAE), an animal model of MS, as compared to control mice. Interestingly, weekly supplementation of mouse and human recombinant p40 ameliorated clinical symptoms and disease progression of EAE. On the other hand, IL-12, IL-23, and p402 did not exhibit such inhibitory effect. In addition to EAE, p40 also suppressed collagen-induced arthritis in mice. Using IL-12Rβ1-/-, IL-12Rβ2-/-, and IL-12Rβ1+/-/IL-12Rβ2-/- mice, we observed that p40 required IL-12Rβ1, but not IL-12Rβ2, to suppress EAE. Interestingly, p40 arrested IL-12-, IL-23-, or p402-mediated internalization of IL-12Rβ1, but neither IL-12Rβ2 nor IL-23R, protected regulatory T cells, and suppressed Th1 and Th17 biasness. These studies identify p40 as an anti-autoimmune cytokine with a biological role different from IL-12, IL-23, and p402 in which it attenuates autoimmune signaling via suppression of IL-12Rβ1 internalization, which may be beneficial in patients with MS and other autoimmune disorders.

Targeting Dendritic Cells with Antigen-Delivering Antibodies for Amelioration of Autoimmunity in Animal Models of Multiple Sclerosis and Other Autoimmune Diseases.

The specific targeting of dendritic cells (DCs) using antigen-delivering antibodies has been established to be a highly efficient protocol for the induction of tolerance and protection from autoimmune processes in experimental autoimmune encephalomyelitis (EAE), a model of multiple sclerosis (MS), as well as in some other animal disease models. As the specific mechanisms of such induced tolerance are being investigated, the newly gained insights may also possibly help to design effective treatments for patients. Here we review approaches applied for the amelioration of autoimmunity in animal models based on antibody-mediated targeting of self-antigens to DCs. Further, we discuss relevant mechanisms of immunological tolerance that underlie such approaches, and we also offer some future perspectives for the application of similar methods in certain related disease settings such as transplantation.

FRET based ratiometric Ca2+ imaging to investigate immune-mediated neuronal and axonal damage processes in experimental autoimmune encephalomyelitis

BackgroundIrreversible axonal and neuronal damage are the correlate of disability in patients suffering from multiple sclerosis (MS). A sustained increase of cytoplasmic free [Ca2+] is a common upstream event of many neuronal and axonal damage processes and could represent an early and potentially reversible step. New methodWe propose a method to specifically analyze the neurodegenerative aspects of experimental autoimmune encephalomyelitis by Förster Resonance Energy Transfer (FRET) imaging of neuronal and axonal Ca2+ dynamics by two-photon laser scanning microscopy (TPLSM). ResultsUsing the genetically encoded Ca2+ sensor TN-XXL expressed in neurons and their corresponding axons, we confirm the increase of cytoplasmic free [Ca2+] in axons and neurons of autoimmune inflammatory lesions compared to those in non-inflamed brains. We show that these relative [Ca2+] increases were associated with immune-neuronal interactions. Comparison with existing methodsIn contrast to Ca2+-sensitive dyes the use of a genetically encoded Ca2+ sensor allows reliable intraaxonal free [Ca2+] measurements in living anesthetized mice in health and disease. This method detects early axonal damage processes in contrast to e.g. cell/axon morphology analysis, that rather detects late signs of neurodegeneration. ConclusionsThus, we describe a method to analyze and monitor early neuronal damage processes in the brain in vivo.

Role of inactivated influenza vaccine in regulation of autoimmune processes in experimental autoimmune encephalomyelitis

Experimental autoimmune encephalomyelitis (EAE) is characterized by appearance of anti-myelin autoantibodies in the blood and with the increased expression of MHC (major histocompatibility complex) class I and II antigens in the brain tissue. Although there is an evidence of possible linkage between influenza vaccination and development of autoimmune processes, the precise mechanisms of action of this vaccine on EAE-induction is still unclear. In this study, effects of influenza vaccine on clinical sign, antimyelin antibody titer in the blood by ELISA test and expression of MHC class I and II molecules immunohistochemistry were examined in the brain of C57BL mice with EAE. EAE was induced by MOG35–55 protein in 16 of 32 mice. Influenza split vaccine was administered to eight MOG-induced EAE mice and to eight previously nontreated mice. A significant increase of anti-influenza antibody was detected in vaccinated mice compared to nontreated mice. Also, significant increase of antimyelin antibodies was detected in mice with EAE compared to vaccinated group without EAE and control group, respectively. In EAE-influenza vaccinated mice, a mild but not significant increase of antimyelin antibodies was detected, compared to EAE mice. High expression of MHC-II and mild expression of MHC-I were detected in the brain of mice with EAE. No expressions were detected in vaccinated and normal intact brains. Similar staining was found between EAE-vaccinated and EAE group in both MHC-I and MHC-II expression. The results obtained show that influenza vaccine has no significant influence on EAE induction and severity of autoimmune processes.

Influenza split vaccine in regulation of autoimmune processes in experimental autoimmune encephalomyelitis

Influenza split vaccine in regulation of autoimmune processes in experimental autoimmune encephalomyelitis

N-acetyl-L-cysteine ameliorates the inflammatory disease process in experimental autoimmune encephalomyelitis in Lewis rats

We report that N-acetyl-L-cysteine (NAC) treatment blocked induction of TNF-α, IL-1β, IFN-γ and iNOS in the CNS and attenuated clinical disease in the myelin basic protein induced model of experimental allergic encephalomyelitis (EAE) in Lewis rats. Infiltration of mononuclear cells into the CNS and induction of inflammatory cytokines and iNOS in multiple sclerosis (MS) and EAE have been implicated in subsequent disease progression and pathogenesis. To understand the mechanism of efficacy of NAC against EAE, we examined its effect on the production of cytokines and the infiltration of inflammatory cells into the CNS. NAC treatment attenuated the transmigration of mononuclear cells thereby lessening the neuroinflammatory disease. Splenocytes from NAC-treated EAE animals showed reduced IFN-γ production, a Th1 cytokine and increased IL-10 production, an anti-inflammatory cytokine. Further, splenocytes from NAC-treated EAE animals also showed decreased nitrite production when stimulated in vitro by LPS. These observations indicate that NAC treatment may be of therapeutic value in MS against the inflammatory disease process associated with the infiltration of activated mononuclear cells into the CNS.

Immunoglobulins Treatment in Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis

Intravenously administered immunoglobulins (IgG) treatment has several modes of action that can regulate the immune response during different steps of the inflammatory process in experimental autoimmune encephalomyelitis (EAE) and Multiple Sclerosis (MS). The immunomodulatory effects IgG are largely dependent on their ability to interact with membrane molecules of lymphocytes and monocytes. Better understanding of these mechanisms of action in relation to the pathogenesis of MS, is important in order to decide the time of initiation and the duration of treatment in MS patients. In order to have the best beneficial effect on disease course, future research should focus on the initial events that activate the disease and on the early treatment modalities of IgG in MS.

Restricted immune responses lead to CNS demyelination and axonal damage

Although autoreactive T-cells have a pivotal role in initiating the inflammatory process in experimental autoimmune encephalomyelitis (EAE) and multiple sclerosis (MS), recent evidence suggests a relevant role for autoantibodies specific for myelin proteins as well. To examine the role of B-cells in the cerebrospinal fluid of patients with MS, we analyzed the V H gene usage in ten MS patients by PCR technologies. Analysis of HCDR3 length revealed an oligoclonal accumulation of B-cells. Sequence analysis of the V H3 and V H4 γ transcripts of two MS individuals demonstrated that this accumulation was related to the expansion and somatic diversification of a limited groups of B-cell clones. These findings are indicative of a chronic and intense antigenic stimulation occurring in the CNS. Animal models, such as EAE, are of particular importance in order to elucidate the pathogenetic effector mechanisms in autoimmune demyelination. In a non-human primate model of EAE, we describe that the immunodominant T-cell epitope is presented exclusively by a monomorphic DRB1 allele, suggesting that susceptibility to EAE may be linked to this unique restriction and, therefore, providing a possible mechanism for MHC linkage to diseases. Moreover, we report on the presence of inflammation, sharp demyelination and axonal damage in EAE induced with whole myelin as well as with recombinant myelin oligodendrocyte glycoprotein (MOG), but not with myelin basic protein alone. The presence of axonal pathology was supported by immunohistochemistry with anti-amyloid precursor protein and anti-non phosphorilated neurofilaments monoclonal antibodies within early active demyelinated plaques. These findings suggest that axonal damage may be an early event in the pathogenesis of autoimmune demyelinating diseases of the CNS and highlights the importance of animal models in which therapies targeting repair and axonal survival may be exploited.

Protection against experimental encephalomyelitis: Idiotypic autoregulation induced by a non-encephalitogenic T cell clone expressing a cross-reactive T cell receptor V gene: H. Offner, M. Vainiene, D. Gold, W. Morrison, G. Hashim and A. Vandenbark. Portland, OR.

The recovery process in experimental autoimmune encephalomyelitis (EAE) in Lewis rats is characterized by an increasing diversity of T cell clones directed at secondary epitopes of myelin basic protein. Of particular interest, residues 55 to 69 of guinea pig basic protein could induce protection against EAE. A nonencephalitogenic T cell clone, C455-69, that was specific for this epitope transferred protection against both active and passive EAE. Clone C4 was found to express V beta 8.6 in its Ag receptor, and residues 39 to 59 of the TCR V beta 8.6 sequence were found to be highly crossreactive with the corresponding residues 39 to 59 of TCR V beta 8.2, which is known to induce protective anti-idiotypic T cells and antibodies. Like the TCR V beta 8.2 peptide, the V beta 8.6 sequence induced autoregulation and provided effective treatment of established EAE. Thus, the EAE-protective effect of the guinea pig basic protein 55-69 sequence was most likely mediated by T cell clones such as C4 that could efficiently induce anti-TCR immunity directed at a cross-reactive regulatory idiotope.

Protection against experimental encephalomyelitis. Idiotypic autoregulation induced by a nonencephalitogenic T cell clone expressing a cross-reactive T cell receptor V gene.

The recovery process in experimental autoimmune encephalomyelitis (EAE) in Lewis rats is characterized by an increasing diversity of T cell clones directed at secondary epitopes of myelin basic protein. Of particular interest, residues 55 to 69 of guinea pig basic protein could induce protection against EAE. A nonencephalitogenic T cell clone, C455-69, that was specific for this epitope transferred protection against both active and passive EAE. Clone C4 was found to express V beta 8.6 in its Ag receptor, and residues 39 to 59 of the TCR V beta 8.6 sequence were found to be highly crossreactive with the corresponding residues 39 to 59 of TCR V beta 8.2, which is known to induce protective anti-idiotypic T cells and antibodies. Like the TCR V beta 8.2 peptide, the V beta 8.6 sequence induced autoregulation and provided effective treatment of established EAE. Thus, the EAE-protective effect of the guinea pig basic protein 55-69 sequence was most likely mediated by T cell clones such as C4 that could efficiently induce anti-TCR immunity directed at a cross-reactive regulatory idiotope.