myelin-oligodendrocyte-glycoprotein-(35-55) and Demyelinating-Diseases

The renin angiotensin system (RAS), which is classically known for blood pressure regulation, has functions beyond this. There are two axes of RAS that work to counterbalance each other and are active throughout the body, including the CNS. The pathological axis, consisting of angiotensin II (A1-8), angiotensin converting enzyme (ACE) and the angiotensin II type 1 receptor (AT1R), is upregulated in many CNS diseases, including multiple sclerosis (MS). MS is an autoimmune and neurodegenerative disease of the CNS characterized by inflammation, demyelination and axonal degeneration. Published research has described increased expression of AT1R and ACE in tissues from MS patients and in animal models of MS such as experimental autoimmune encephalomyelitis (EAE). In contrast to the pathological axis, little is known about the protective axes of RAS in MS and EAE. In other neurological conditions the protective axis, which includes A1-7, ACE2, angiotensin II type 2 receptor and Mas receptor, has been shown to have anti-inflammatory, regenerative and neuroprotective effects. Here we show, for the first time, changes in the protective arm of RAS in both EAE and MS CNS tissue. We observed a significant increase in expression of the protective arm during stages of disease stabilization in EAE, and in MS tissue showing evidence of remyelination. These data provide evidence that the protective arm of RAS, through both ligand and receptor expression, is associated with reductions in the pathological processes that occur in the earlier stages of MS and EAE, possibly slowing the neurodegenerative process and enhancing neural repair. Graphical Abstract.

Topics: Animals; Brain; Cells, Cultured; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Humans; Male; Mice; Mice, Inbred C57BL; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Renin-Angiotensin System; Spinal Cord

Promoting remyelination is recognized as a novel strategy to foster repair in neurodegenerative demyelinating diseases, such as multiple sclerosis. In this respect, the receptor GPR17, recently emerged as a new target for remyelination, is expressed by early oligodendrocyte precursors (OPCs) and after a certain differentiation stage it has to be downregulated to allow progression to mature myelinating oligodendrocytes. Here, we took advantage of the first inducible GPR17 reporter mouse line (GPR17-iCreER

Topics: Animals; Cuprizone; Demyelinating Diseases; Disease Models, Animal; Female; Green Fluorescent Proteins; Male; Mice, Inbred C57BL; Mice, Transgenic; Myelin-Oligodendrocyte Glycoprotein; Nerve Tissue Proteins; Oligodendrocyte Precursor Cells; Peptide Fragments; Receptors, G-Protein-Coupled; Remyelination; Spinal Cord

Multiple sclerosis (MS) is a poorly understood disease mechanistically. MOG35-55 peptide induced experimental autoimmune encephalomyelitis (EAE) is a broadly used model to study MS. Using this model we have earlier shown that the antioxidant tempol or the small molecule inhibitor of p38 SB203580 can effectively prevent EAE progression. This effect was mediated by means of regulating immune inflammation, signaling by the p38MAPK-SGK1 pathway, and oxidative stress. However, there is a need to test drugs that can be used in pharmacological intervention of EAE. Given that nordihydroguaiaretic Acid (NDGA) has been shown to possess anti-oxidant activity and capacity of antagonizing autoimmune inflammation, we tested the effect of NDGA in ameliorating EAE in the current study. NDGA showed significant beneficial effect against EAE with both anti-inflammation and antioxidant activity. NDGA could weaken the immune inflammation at least partly by inhibiting the oxidant stress-p38MAPK-SGK1 pathway representing a target for putative pharmacological intervention. © 2018 IUBMB Life, 70(5):432-436, 2018.

Topics: Animals; Demyelinating Diseases; Disease Progression; Encephalomyelitis, Autoimmune, Experimental; Female; Gene Expression Regulation; Heme Oxygenase-1; Immediate-Early Proteins; Immunologic Factors; Injections, Intraperitoneal; Masoprocol; Mice; Mice, Inbred C57BL; Myelin-Oligodendrocyte Glycoprotein; Neuroprotective Agents; Oxidation-Reduction; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Peptide Fragments; Protein Serine-Threonine Kinases

Leukocyte entry into the CNS is a crucial step in the development of multiple sclerosis and its animal model experimental autoimmune encephalomyelitis (EAE). Adhesion molecules mediating the docking of leukocytes to the endothelium of the blood-brain barrier (BBB) represent valuable targets for interference with the disease. However, little is known about the adhesion and signaling mechanisms in endothelial cells that mediate the diapedesis through the BBB. Here, we show that conditional Tie-2-Cre driven gene inactivation of CD99L2 inhibits leukocyte entry into the CNS during active MOG

Topics: 12E7 Antigen; Animals; Basement Membrane; Blood-Brain Barrier; Cells, Cultured; Chemotaxis, Leukocyte; Cytokines; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Endothelial Cells; Female; Gene Expression Profiling; Gene Silencing; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Radiation Chimera; Transendothelial and Transepithelial Migration

CD40-CD154 interaction is critically involved in autoimmune diseases, and CD4 T cells play a dominant role in the Experimental Autoimmune Encephalomyelitis (EAE) model of Multiple Sclerosis (MS). CD4 T cells expressing CD40 (Th40) are pathogenic in type I diabetes but have not been evaluated in EAE. We demonstrate here that Th40 cells drive a rapid, more severe EAE disease course than conventional CD4 T cells. Adoptively transferred Th40 cells are present in lesions in the CNS and are associated with wide spread demyelination. Primary Th40 cells from EAE-induced donors adoptively transfer EAE without further in-vitro expansion and without requiring the administration of the EAE induction regimen to the recipient animals. This has not been accomplished with primary, non-TCR-transgenic donor cells previously. If co-injection of Th40 donor cells with Freund's adjuvant (CFA) in the recipient animals is done, the disease course is more severe. The CFA component of the EAE induction regimen causes generalized inflammation, promoting expansion of Th40 cells and infiltration of the CNS, while MOG-antigen shapes the antigen-specific TCR repertoire. Those events are both necessary to precipitate disease. In MS, viral infections or trauma may induce generalized inflammation in susceptible individuals with subsequent disease onset. It will be important to further understand the events leading up to disease onset and to elucidate the contributions of the Th40 T cell subset. Also, evaluating Th40 levels as predictors of disease onset would be highly useful because if either the generalized inflammation event or the TCR-honing can be interrupted, disease onset may be prevented.

Topics: Adoptive Transfer; Animals; Blotting, Western; Brain; CD4-Positive T-Lymphocytes; CD40 Antigens; Cell Movement; Cell Proliferation; Central Nervous System; Cytokines; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Female; Flow Cytometry; Freund's Adjuvant; Interferon-gamma; Mice, Inbred C57BL; Mice, SCID; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Spinal Cord

A single peripheral dose of CNS-binding IgMs promote remyelination and preserve axons in a number of animal models of neurologic disease. A myelin-binding recombinant human IgM (rHIgM22) is presently in a safety trial in MS patients following an acute MS exacerbation. rHIgM22 (directed against oligodendrocytes) or rHIgM12 (directed against neurons) were administered to mice with MOG-induced experimental autoimmune encephalomyelitis (EAE) with study endpoints: clinical deficits and brain and spinal cord pathology. IgMs were administered at a therapeutic dose of 100 μ g intra peritoneal at the time of immunization (day -1, 0, +$1), disease onset (15 days) or peak of the disease (28 days). Disease course was not worsened by either human IgM regardless of the time of treatment. Of note, the human IgM that recognizes a carbohydrate epitope on gangliosides and NCAM, rHIgM12, reduced brain pathology when given at time of immunization or at onset of disease, but did not reduce clinical deficits or spinal cord disease burden. Hence, treatment with rHIgM12 resulted in marked reduction in meningeal inflammation. Data consistent with the hypothesis that in the EAE model this molecule has an immune-modulatory effect. Treatment with an anti-CD4 blocking IgG prevented both clinical course and CNS pathology. This pre-clinical study further supports the safety of therapeutic CNS-binding human IgMs in the presence of autoimmunity and clearly differentiates them from IgGs directed against MOG or aquaporin-4 that worsen neurologic disease.

Topics: Animals; Brain; Cognitive Dysfunction; Demyelinating Diseases; Drug Administration Schedule; Encephalomyelitis, Autoimmune, Experimental; Female; Freund's Adjuvant; Humans; Immunoglobulin M; Immunologic Factors; Injections, Intraperitoneal; Mice; Mice, Inbred C57BL; Myelin Sheath; Myelin-Oligodendrocyte Glycoprotein; Neural Cell Adhesion Molecule L1; Neurons; Neuroprotective Agents; Oligodendroglia; Peptide Fragments; Protein Binding; Recombinant Proteins; Sialic Acids; Spinal Cord

Recently, parasite infections or parasite-derived products have been suggested as a therapeutic strategy with suppression of immunopathology, which involves the induction of regulatory T cells or/and T helper type 2 (Th2) responses. In a recent study, researchers reported that constructed recombinant galectin (rTl-gal) isolated from an adult worm of the gastrointestinal nematode parasite Toxascaris leonina attenuated clinical symptoms of inflammatory bowel disease in mice treated with dextran sulphate sodium. Noting the role of rTl-gal in inflammatory disease, we attempted to investigate the effect of the parasite via its rTl-gal on neuronal autoimmune disease using experimental autoimmune encephalomyelitis (EAE), a mouse inflammatory and demyelinating autoimmune disease model of human multiple sclerosis. In this model, rTl-gal-treated experimental autoimmune encephalomyelitis (EAE) mice failed to recover after the peak of the disease, leading to persistent central nervous system (CNS) damage, such as demyelination, gliosis and axonal damage. Further, rTl-gal-treated EAE mice markedly increased the number of CD45R/B220(+) B cells in both infiltrated inflammation and the periphery, along with the increased production of autoantibody [anti-myelin oligodendrocyte glycoprotein (MOG)35-55 ] in serum at chronic stage. Upon antigen restimulation, rTl-gal treatment affected the release of overall cytokines, especially interferon (IFN)-γ and tumour necrosis factor (TNF)-α. Our results suggest that galectin isolated from a gastrointestinal parasite can deliver a harmful effect to EAE contrary to its beneficial effect on inflammatory bowel disease.

Topics: Animals; Autoantibodies; Axons; B-Lymphocyte Subsets; Cytokines; Demyelinating Diseases; Disease Models, Animal; Disease Progression; Encephalomyelitis, Autoimmune, Experimental; Female; Galectins; Gliosis; Immunomodulation; Leukocyte Common Antigens; Mice; Myelin-Oligodendrocyte Glycoprotein; Parasites; Peptide Fragments; Severity of Illness Index; Spinal Cord

Multiple sclerosis (MS) is a demyelinating disease of the CNS characterized by inflammation and neurodegeneration. Animal models that enable the study of remyelination in the context of ongoing inflammation are greatly needed for the development of novel therapies that target the pathological inhibitory cues inherent to the MS plaque microenvironment. We report the development of an innovative animal model combining cuprizone-mediated demyelination with transfer of myelin-reactive CD4(+) T cells. Characterization of this model reveals both Th1 and Th17 CD4(+) T cells infiltrate the CNS of cuprizone-fed mice, with infiltration of Th17 cells being more efficient. Infiltration correlates with impaired spontaneous remyelination as evidenced by myelin protein expression, immunostaining, and ultrastructural analysis. Electron microscopic analysis further reveals that demyelinated axons are preserved but reduced in caliber. Examination of the immune response contributing to impaired remyelination highlights a role for peripheral monocytes with an M1 phenotype. This study demonstrates the development of a novel animal model that recapitulates elements of the microenvironment of the MS plaque and reveals an important role for T cells and peripheral monocytes in impairing endogenous remyelination in vivo. This model could be useful for testing putative MS therapies designed to enhance remyelination in the setting of active inflammation, and may also facilitate modeling the pathophysiology of denuded axons, which has been a challenge in rodents because they typically remyelinate very quickly.

Topics: Adoptive Transfer; Animals; Cell Polarity; Cells, Cultured; Central Nervous System; Cuprizone; Demyelinating Diseases; Disease Models, Animal; Freund's Adjuvant; Interleukin-17; Leukocyte Common Antigens; Mice; Mice, Inbred C57BL; Mice, Transgenic; Monoamine Oxidase Inhibitors; Monocytes; Myelin Proteins; Myelin Sheath; Myelin-Oligodendrocyte Glycoprotein; Neutrophil Infiltration; Peptide Fragments; Regeneration; Th17 Cells; Time Factors

Mesenchymal stem cells (MSCs) are pleiotropic cells with potential therapeutic benefits for a wide range of diseases. Because of their immunomodulatory properties they have been utilized to treat autoimmune diseases such as multiple sclerosis (MS), which is characterized by demyelination. The microenvironment surrounding MSCs is thought to affect their differentiation and phenotype, which could in turn affect the efficacy. We thus sought to dissect the potential for differential impact of MSCs on central nervous system (CNS) disease in T cell mediated and non-T cell mediated settings using the MOG35-55 experimental autoimmune encephalomyelitis (EAE) and cuprizone-mediated demyelination models, respectively. As the pathogeneses of MS and EAE are thought to be mediated by IFNγ-producing (TH1) and IL-17A-producing (TH17) effector CD4+ T cells, we investigated the effect of MSCs on the development of these two key pathogenic cell groups. Although MSCs suppressed the activation and effector function of TH17 cells, they did not affect TH1 activation, but enhanced TH1 effector function and ultimately produced no effect on EAE. In the non- T cell mediated cuprizone model of demyelination, MSC administration had a positive effect, with an overall increase in myelin abundance in the brain of MSC-treated mice compared to controls. These results highlight the potential variability of MSCs as a biologic therapeutic tool in the treatment of autoimmune disease and the need for further investigation into the multifaceted functions of MSCs in diverse microenvironments and the mechanisms behind the diversity.

Topics: Animals; CD4-Positive T-Lymphocytes; Cell Death; Cell Proliferation; Corpus Callosum; Cuprizone; Cytokines; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Female; Lymphocyte Subsets; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice, Inbred C57BL; Myelin-Oligodendrocyte Glycoprotein; Oligodendroglia; Peptide Fragments

Although multiple sclerosis (MS) has been associated with the coagulation system, the temporal and spatial regulation of coagulation activity in neuroinflammatory lesions is unknown. Using a novel molecular probe, we characterized the activity pattern of thrombin, the central protease of the coagulation cascade, in experimental autoimmune encephalomyelitis. Thrombin activity preceded onset of neurological signs, increased at disease peak, and correlated with fibrin deposition, microglial activation, demyelination, axonal damage, and clinical severity. Mice with a genetic deficit in prothrombin confirmed the specificity of the thrombin probe. Thrombin activity might be exploited for developing sensitive probes for preclinical detection and monitoring of neuroinflammation and MS progression.

Topics: Animals; Axons; Blood Coagulation Factors; Connexin 30; Connexins; Demyelinating Diseases; Disease Models, Animal; Disease Progression; Encephalomyelitis, Autoimmune, Experimental; Fibrin; Green Fluorescent Proteins; Mice; Mice, Inbred C57BL; Mice, Transgenic; Myelin Basic Protein; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Poly I-C; Thrombin

The adoptive transfer of myelin-reactive T cells into wild-type hosts results in spinal cord inflammation and ascending paralysis, referred to as conventional experimental autoimmune encephalomyelitis (EAE), as opposed to brainstem inflammation and ataxia, which characterize disease in IFN-γRKO hosts (atypical EAE). In this article, we show that atypical EAE correlates with preferential upregulation of CXCL2 in the brainstem, and is driven by CXCR2-dependent recruitment of neutrophils. In contrast, conventional EAE is associated with upregulation of CCL2 in the spinal cord, and is driven by recruitment of monocytes via a partially CCR2-dependent pathway. This study illustrates how regional differences in chemokine expression within a target organ shape the spatial pattern and composition of autoimmune infiltrates, leading to disparate clinical outcomes.

Topics: Animals; Antigens, CD; Antigens, Differentiation, T-Lymphocyte; Brain Stem; CD4-Positive T-Lymphocytes; Central Nervous System; Chemokines; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Flow Cytometry; Immunophenotyping; Inflammation; Interferon gamma Receptor; Interleukin-12; Interleukin-17; Interleukin-2 Receptor alpha Subunit; Lectins, C-Type; Mice; Mice, Inbred C57BL; Mice, Knockout; Microscopy, Confocal; Monocytes; Myelin-Oligodendrocyte Glycoprotein; Neutrophils; Peptide Fragments; Receptors, CCR2; Receptors, Interferon; Receptors, Interleukin-8B

Multiple sclerosis (MS) is an autoimmune chronic disease of the central nervous system (CNS) characterized by immune-mediated inflammation, demyelination and subsequent axonal damage. Gene expression profiling showed that Nurr1, an orphan nuclear receptor, is down-regulated in peripheral blood mononuclear cells of MS patients. Nurr1 exerts an anti-inflammatory role repressing the activity of the pro-inflammatory transcription factor NF-kB. Here, we report that the preventive treatment with isoxazolo-pyridinone 7e, an activator of Nurr1 signaling pathway, reduces the incidence and the severity of a MS murine model, i.e. experimental autoimmune encephalomyelitis (EAE). The compound is able to attenuate inflammation and neurodegeneration in spinal cords of EAE mice by an NF-kB pathway-dependent process.

Topics: Animals; Axons; Cell Count; Demyelinating Diseases; Down-Regulation; Encephalomyelitis, Autoimmune, Experimental; Female; Isoxazoles; Macrophages; Mice, Inbred C57BL; Myelin-Oligodendrocyte Glycoprotein; NF-kappa B; Nuclear Receptor Subfamily 4, Group A, Member 2; Oxazoles; Peptide Fragments; Pyrimidinones; Signal Transduction; Spinal Cord; T-Lymphocytes

Multiple sclerosis (MS) is an autoimmune disease characterized by inflammation and neurodegeneration. Current MS treatments were designed to reduce inflammation in MS rather than directly to prevent neurodegeneration. Estrogen has well-documented neuroprotective effects in a variety of disorders of the CNS, including experimental autoimmune encephalomyelitis (EAE), the most widely used mouse model of MS. Treatment with an estrogen receptor-β (ERβ) ligand is known to ameliorate clinical disease effectively and provide neuroprotection in EAE. However, the protective effects of this ERβ ligand have been demonstrated only when administered prior to disease (prophylactically). Here we tested whether ERβ ligand treatment could provide clinical protection when treatment was initiated after onset of disease (therapeutically). We found that therapeutic treatment effectively ameliorated clinical disease in EAE. Specifically, ERβ ligand-treated animals exhibited preserved axons and myelin compared with vehicle-treated animals. We observed no difference in the number of T lymphocytes, macrophages, or microglia in the CNS of vehicle- vs. ERβ ligand-treated animals. Our findings show that therapeutically administered ERβ ligand successfully treats clinical EAE, bearing translational relevance to MS as a candidate neuroprotective agent.

Topics: Animals; Axons; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Freund's Adjuvant; Mice; Mice, Inbred C57BL; Myelin-Oligodendrocyte Glycoprotein; Neuroprotective Agents; Nitriles; Peptide Fragments; Propionates; Receptors, Estrogen; Severity of Illness Index

Fractalkine, a chemokine anchored to neurons or peripheral endothelial cells, serves as an adhesion molecule or as a soluble chemoattractant. Fractalkine binds CX3CR1 on microglia and circulating monocytes, dendritic cells, and NK cells. The aim of this study is to determine the role of CX3CR1 in the trafficking and function of myeloid cells to the CNS during experimental autoimmune encephalomyelitis (EAE). Our results show that, in models of active EAE, Cx3cr1(-/-) mice exhibited more severe neurologic deficiencies. Bone marrow chimeric mice confirmed that CX3CR1 deficiency in bone marrow enhanced EAE severity. Notably, CX3CR1 deficiency was associated with an increased accumulation of CD115(+)Ly6C(-)CD11c(+) dendritic cells into EAE-affected brains that correlated with enhanced demyelination and neuronal damage. Furthermore, higher IFN-γ and IL-17 levels were detected in cerebellar and spinal cord tissues of CX3CR1-deficient mice. Analyses of peripheral responses during disease initiation revealed a higher frequency of IFN-γ- and IL-17-producing T cells in lymphoid tissues of CX3CR1-deficient as well as enhanced T cell proliferation induced by CX3CR1-deficient dendritic cells. In addition, adoptive transfer of myelin oligodendrocyte glycoprotein35-55-reactive wild-type T cells induced substantially more severe EAE in CX3CR1-deficient recipients when compared with wild-type recipients. Collectively, the data demonstrate that besides its role in chemoattraction, CX3CR1 is a key regulator of myeloid cell activation contributing to the establishment of adaptive immune responses.

Topics: Adaptive Immunity; Animals; Antigens, Ly; Autoimmunity; Bone Marrow Cells; CD11c Antigen; Cell Proliferation; Central Nervous System; Chimera; CX3C Chemokine Receptor 1; Demyelinating Diseases; Dendritic Cells; Encephalomyelitis, Autoimmune, Experimental; Inflammation; Interferon-gamma; Interleukin-1; Interleukin-17; Lymphocyte Activation; Lymphoid Tissue; Mice; Mice, Inbred C57BL; Mice, Knockout; Myelin-Oligodendrocyte Glycoprotein; Myeloid Cells; Peptide Fragments; Receptor, Macrophage Colony-Stimulating Factor; Receptors, Chemokine; Receptors, Cytokine; Receptors, HIV; T-Lymphocytes

Neuromyelitis optica (NMO) is a devastating inflammatory disorder of the optic nerves and spinal cord characterized by frequently recurring exacerbations of humoral inflammation. NMO is associated with the highly specific NMO-IgG biomarker, an antibody that binds the aquaporin-4 water channel. Aquaporin-4 is present on glial endfeet in the central nervous system (CNS). In humans, the NMO-IgG portends more frequent exacerbations and a worse long-term clinical outcome.. We tested the longer-term outcome of mice with EAE injected with NMO-IgG and followed them for 60 days. Clinical exams and pathology of the spinal cord and optic nerves were compared to mice that received control human IgG.. Passively transferred human NMO-IgG leads to more severe neurology disability over two months after onset of disease. Clinical worsening is associated with an increased concentration of large demyelinating lesions primarily to subpial AQP4-rich regions of the spinal cord.. NMO-IgG is pathogenic in the context of EAE in mice.

Topics: Animals; Antigens, CD; Antigens, Ly; Aquaporin 4; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Humans; Immunoglobulin G; Mice; Mice, Inbred C57BL; Myelin Sheath; Myelin-Oligodendrocyte Glycoprotein; Neuromyelitis Optica; Optic Nerve; Peptide Fragments; Spinal Cord; Time Factors

Multiple sclerosis involves demyelination and axonal degeneration of the central nervous system. The molecular mechanisms of axonal degeneration are relatively unexplored in both multiple sclerosis and its mouse model, experimental autoimmune encephalomyelitis. We previously reported that targeting the axonal growth inhibitor, Nogo-A, may protect against neurodegeneration in experimental autoimmune encephalomyelitis; however, the mechanism by which this occurs is unclear. We now show that the collapsin response mediator protein 2 (CRMP-2), an important tubulin-associated protein that regulates axonal growth, is phosphorylated and hence inhibited during the progression of experimental autoimmune encephalomyelitis in degenerating axons. The phosphorylated form of CRMP-2 (pThr555CRMP-2) is localized to spinal cord neurons and axons in chronic-active multiple sclerosis lesions. Specifically, pThr555CRMP-2 is implicated to be Nogo-66 receptor 1 (NgR1)-dependent, since myelin oligodendrocyte glycoprotein (MOG)(35-55)-induced NgR1 knock-out (ngr1(-)(/)(-)) mice display a reduced experimental autoimmune encephalomyelitis disease progression, without a deregulation of ngr1(-)(/)(-) MOG(35-55)-reactive lymphocytes and monocytes. The limitation of axonal degeneration/loss in experimental autoimmune encephalomyelitis-induced ngr1(-)(/)(-) mice is associated with lower levels of pThr555CRMP-2 in the spinal cord and optic nerve during experimental autoimmune encephalomyelitis. Furthermore, transduction of retinal ganglion cells with an adeno-associated viral vector encoding a site-specific mutant T555ACRMP-2 construct, limits optic nerve axonal degeneration occurring at peak stage of experimental autoimmune encephalomyelitis. Therapeutic administration of the anti-Nogo(623-640) antibody during the course of experimental autoimmune encephalomyelitis, associated with an improved clinical outcome, is demonstrated to abrogate the protein levels of pThr555CRMP-2 in the spinal cord and improve pathological outcome. We conclude that phosphorylation of CRMP-2 may be downstream of NgR1 activation and play a role in axonal degeneration in experimental autoimmune encephalomyelitis and multiple sclerosis. Blockade of Nogo-A/NgR1 interaction may serve as a viable therapeutic target in multiple sclerosis.

Topics: Adult; Analysis of Variance; Animals; Antibodies; Axons; CD3 Complex; Cell Line, Tumor; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Gene Expression Regulation; Glycoproteins; GPI-Linked Proteins; Green Fluorescent Proteins; Humans; Immunoprecipitation; Intercellular Signaling Peptides and Proteins; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Middle Aged; Multiple Sclerosis; Mutation; Myelin Proteins; Myelin-Oligodendrocyte Glycoprotein; Nerve Degeneration; Nerve Tissue Proteins; Neuroblastoma; Neurofilament Proteins; Nogo Receptor 1; Optic Nerve; Peptide Fragments; Phosphorylation; Receptors, Cell Surface; Retinal Ganglion Cells; Severity of Illness Index; Silver Staining; Spinal Cord; tau Proteins; Time Factors; Transduction, Genetic; Tubulin

Studies with multiple sclerosis patients and animal models of experimental autoimmune encephalomyelitis (EAE) implicate adenosine and adenosine receptors in modulation of neuroinflammation and brain injury. Although the involvement of the A(1) receptor has been recently demonstrated, the role of the adenosine A(2A) receptor (A(2A)R) in development of EAE pathology is largely unknown. Using mice with genetic inactivation of the A(2A) receptor, we provide direct evidence that loss of the A(2A)R exacerbates EAE pathology in mice. Compared with wild-type mice, A(2A)R knockout mice injected with myelin oligodendroglia glycoprotein peptide had a higher incidence of EAE and exhibited higher neurological deficit scores and greater decrease in body weight. A(2A)R knockout mice displayed increased inflammatory cell infiltration and enhanced microglial cell activation in cortex, brainstem, and spinal cord. In addition, demyelination and axonal damage in brainstem were exacerbated, levels of Th1 cytokines increased, and Th2 cytokines decreased. Collectively, these findings suggest that extracellular adenosine acting at A(2A)Rs triggers an important neuroprotective mechanism. Thus, the A(2A) receptor is a potential target for therapeutic approaches to multiple sclerosis.

Topics: Adenosine A1 Receptor Antagonists; Animals; Astrocytes; Axons; Brain Injuries; Cell Proliferation; Cells, Cultured; Cerebral Cortex; Cytokines; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Enzyme-Linked Immunosorbent Assay; Female; Filtration; Flow Cytometry; Freund's Adjuvant; Gene Expression Regulation; Mice; Mice, Inbred C57BL; Mice, Knockout; Microglia; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Protein Binding; Receptor, Adenosine A2A; RNA, Messenger; Spinal Cord; Spleen; Statistics, Nonparametric; Tritium; Xanthines

Cyclic GMP (cGMP)-mediated pathways regulate inflammatory responses in immune and CNS cells. Recently, cGMP phosphodiesterase inhibitors such as sildenafil, commonly used to treat sexual dysfunction in humans including multiple sclerosis (MS) patients, have been reported to be neuroprotective in animal models of stroke, Alzheimer's disease, and focal brain lesion. In this work, we have examined if sildenafil ameliorates myelin oligodendrocyte glycoprotein peptide (MOG₃₅₋₅₅)-induced experimental autoimmune encephalomyelitis (EAE), a mouse model of MS. We show for the first time that treatment with sildenafil after disease onset markedly reduces the clinical signs of EAE by preventing axonal loss and promoting remyelination. Furthermore, sildenafil decreases CD3+ leukocyte infiltration and microglial/macrophage activation in the spinal cord, while increasing forkhead box transcription factor 3-expressing T regulatory cells (Foxp3 Tregs). However, sildenafil treatment did not significantly affect MOG₃₅₋₅₅-stimulated proliferation or release of Th1/Th2 cytokines in splenocytes but decreased ICAM-1 in spinal cord infiltrated cells. The presence of reactive astrocytes forming scar-like structures around infiltrates was enhanced by sildenafil suggesting a possible mechanism for restriction of leukocyte spread into healthy parenchyma. These results highlight novel actions of sildenafil that may contribute to its beneficial effects in EAE and suggest that treatment with this widely used and well-tolerated drug may be a useful therapeutic intervention to ameliorate MS neuropathology.

Topics: Animals; CD3 Complex; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Forkhead Transcription Factors; Gene Expression Regulation; Glial Fibrillary Acidic Protein; Gliosis; Glycoproteins; Intercellular Adhesion Molecule-1; Mice; Mice, Inbred C57BL; Myelin-Oligodendrocyte Glycoprotein; Neurofilament Proteins; Peptide Fragments; Phosphodiesterase 5 Inhibitors; Piperazines; Purines; Sildenafil Citrate; Spinal Cord; Sulfones; Time Factors

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by inflammation, but also degenerative changes. Besides neurological deficits, the rate of affective disorders such as depression and anxiety is at least six fold increased. Many aspects of MS can be mimicked in the animal model of myelin oligodendrocyte glycoprotein experimental autoimmune encephalomyelitis (MOG-EAE). Here we investigate behavioral changes in C57BL/6 mice suffering from mild MOG-EAE. In the later phase of the disease, mice were subjected to behavioral tests including the light-dark-box (LD Box), the acoustic startle response (SR) with a pre-pulse inhibition protocol as well as the learned helplessness (LH) paradigm. Behavioral data were correlated with the motor performance in an open field and rotarod test (RR). In the RR and open field, there was no significant difference in the motor performance between controls and mice suffering from mild MOG-EAE. Yet EAE mice displayed an increased anxiety-like behavior with a 23% reduction of the time spent in the bright compartment of the LD Box as well as an increased SR. In the LH paradigm, mice suffering from MOG-EAE were twice as much prone to depressive-like behavior. These changes correlate with an increase of hippocampal tissue tumor necrosis factor alpha levels and neuronal loss in the hippocampus. Modulation of monoaminergic transmission by chronic application of the antidepressant amitriptyline resulted in a decreased startle reaction and increased hippocampal norepinephrine levels. These data imply that chronic inflammation in the CNS may impact on emotional responses in rodent models of anxiety.

Topics: Acoustic Stimulation; Amitriptyline; Analysis of Variance; Animals; Antidepressive Agents, Tricyclic; Anxiety; Central Nervous System; Chromatography, High Pressure Liquid; Cytokines; Dark Adaptation; Demyelinating Diseases; Depression; Disease Models, Animal; Dose-Response Relationship, Drug; Exploratory Behavior; Female; Gene Expression Regulation; Glycoproteins; Helplessness, Learned; Inflammation; Mice; Mice, Inbred C57BL; Motor Activity; Multiple Sclerosis; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Pertussis Toxin; Phosphopyruvate Hydratase; Psychoacoustics; Reflex, Startle; Rotarod Performance Test; Stereotaxic Techniques; Time Factors

Alpha-1-antitrypsin (AAT) is the primary circulating serine protease inhibitor, and is known to exert potent anti-inflammatory effects and to inhibit the progression of several autoimmune diseases. In this study, transgenic mice that over-express surfactant-driven human (h)AAT on the C57BL/6 background were evaluated for resistance to MOG-35-55 peptide-induced experimental autoimmune encephalomyelitis (EAE), compared to WT C57BL/6 control mice. According to the results, sustained levels of circulating hAAT profoundly inhibited induction of clinical signs, inflammatory lesions and demyelination observed in WT mice with EAE, concomitant with enhanced levels of CD4+FoxP3+ Treg cells, reduced secretion of MOG peptide-induced pro-inflammatory cytokines, IL-17, IL-1β & IL-6, diminished expression of caspase-1 and enhanced expression of CCR6. These results implicate hAAT as a potent immunoregulatory agent worthy of further investigation as a potential therapy in human autoimmune diseases including multiple sclerosis.

Topics: alpha 1-Antitrypsin; Animals; Apoptosis; Caspases; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Forkhead Transcription Factors; Glycoproteins; Humans; Inflammation; Interleukin-17; Interleukin-1beta; Interleukin-6; Mice; Mice, Inbred C57BL; Mice, Transgenic; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Receptors, CCR6; Spinal Cord; Spleen; T-Lymphocytes, Regulatory

FTY720 (Fingolimod) is known to have a significant therapeutic effect on experimental autoimmune encephalomyelitis (EAE). Here, we used an EAE mouse model, which had been established by immunizing C57BL/6J mice with a partial peptide of myelin oligodendrocyte glycoprotein (MOG₃₅₋₅₅), to examine the relapse of EAE upon discontinuation of treatment with FTY720 alone or in combination with MOG₃₅₋₅₅. Relapse was confirmed to occur in all animals (n=6) within one week after discontinuation of FTY720, with increase in the number of lymphocytes infiltrating the spinal cord and demyelination. However, in the case of combination therapy with FTY720 and MOG₃₅₋₅₅, relapse following discontinuation of treatment was completely suppressed. The autoantigenic peptide might serve to suppress the clonal selection of relapse-associated autoantigen-specific T cells.

Topics: Animals; Autoantigens; Cyclosporine; Demyelinating Diseases; Drug Therapy, Combination; Encephalomyelitis, Autoimmune, Experimental; Female; Fingolimod Hydrochloride; Glycoproteins; Immunosuppression Therapy; Immunosuppressive Agents; Lymphocyte Activation; Mice; Mice, Inbred C57BL; Multiple Sclerosis; Myelin-Oligodendrocyte Glycoprotein; Nerve Tissue Proteins; Peptide Fragments; Propylene Glycols; Remission Induction; Secondary Prevention; Specific Pathogen-Free Organisms; Sphingosine; Spinal Cord

Dextromethorphan (DM) is a dextrorotary morphinan and a widely used component of cough medicine. Relatively high doses of DM in combination with quinidine are used for the treatment of mood disorders for patients with multiple sclerosis (MS). However, at lower doses, morphinans exert anti-inflammatory activities through the inhibition of NOX2-dependent superoxide production in activated microglia. Here we investigated the effects of high (10 mg/kg, i.p., "DM-10") and low (0.1 mg/kg, i.p., "DM-0.1") doses of DM on the development and progression of mouse experimental autoimmune encephalomyelitis (EAE), an animal model of MS. We found no protection by high dose DM treatment. Interestingly, a minor late attenuation by low dose DM treatment was seen in severe EAE that was characterized by a chronic disease course and a massive spinal cord infiltration of CD45(+) cells including T-lymphocytes, macrophages and neutrophils. Furthermore, in a less severe form of EAE, where lower levels of CD4(+) and CD8(+) T-cells, Iba1(+) microglia/macrophages and no significant infiltration of neutrophils were seen in the spinal cord, the treatment with DM-0.1 was remarkably more beneficial. The effect was the most significant at the peak of disease and was associated with an inhibition of NOX2 expression and a decrease in infiltration of monocytes and lymphocytes into the spinal cord. In addition, chronic treatment with low dose DM resulted in decreased demyelination and reduced axonal loss in the lumbar spinal cord. Our study is the first report to show that low dose DM is effective in treating EAE of moderate severity. Our findings reveal that low dose morphinan DM treatment may represent a new promising protective strategy for treating MS.

Topics: Animals; CD4 Lymphocyte Count; CD8-Positive T-Lymphocytes; Demyelinating Diseases; Dextromethorphan; Dose-Response Relationship, Drug; Encephalomyelitis, Autoimmune, Experimental; Excitatory Amino Acid Antagonists; Glycoproteins; Immunohistochemistry; Lymphocyte Count; Macrophages; Male; Membrane Glycoproteins; Mice; Mice, Inbred C57BL; Microglia; Myelin-Oligodendrocyte Glycoprotein; NADPH Oxidase 2; NADPH Oxidases; Neuroprotective Agents; Neutrophil Infiltration; Peptide Fragments; Reverse Transcriptase Polymerase Chain Reaction; RNA; Spinal Cord; Superoxides; T-Lymphocytes

IL-15 initially identified as a T proliferating cytokine has several structural and biological similarities with IL-2 and has been associated with a number of autoimmune diseases. Because of the scarcity of information available on the role of IL-15 in MS pathogenesis, we have investigated how the absence of IL-15 affected the development of experimental autoimmune encephalomyelitis, a mouse model of MS. Following immunization of IL-15(-/-) and C57BL/6 mice with MOG(35-55), we observed a more severe neurological impairment in the IL-15 knockout mice than in the wild-type group. The enhanced disease severity in IL-15(-/-) mice was associated with greater demyelination in the spinal cord, increased immune cell infiltration and inflammation. These events may be related to the higher CD4/CD8 ratio and the almost absent NK cell activity, congenital immune features of IL-15KO mice. Moreover, we found that the fractalkine receptor CX3CR1 was overexpressed in the spinal cord of IL-15(-/-) mice, mainly localized on infiltrating CD8(+) T cells. How these findings are contributing to the aggravated EAE development in IL-15 KO mice remain unclear and need to be further investigated.

Topics: Analysis of Variance; Animals; CD4 Antigens; CD8 Antigens; CX3C Chemokine Receptor 1; Cytokines; Demyelinating Diseases; Eliminative Behavior, Animal; Encephalomyelitis, Autoimmune, Experimental; Flow Cytometry; Gene Expression Regulation; Glycoproteins; Interleukin-15; Killer Cells, Natural; Mice; Mice, Inbred C57BL; Mice, Knockout; Myelin Basic Protein; Myelin-Oligodendrocyte Glycoprotein; Neutrophil Infiltration; Peptide Fragments; Receptors, Chemokine; Spinal Cord

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the CNS and remyelination in MS ultimately fails. Although strategies to promote myelin repair are eagerly sought, mechanisms underlying remyelination in vivo have been elusive. CXCR2 is expressed on neutrophils and oligodendrocyte lineage cells in the CNS. CXCR2-positive neutrophils facilitate inflammatory demyelination in demyelination models such as experimental autoimmune encephalomyelitis (EAE) and cuprizone intoxication. Systemic injection of a small molecule CXCR2 antagonist at the onset of EAE decreased demyelinated lesions. These results left the cellular target of the CXCR2 antagonist uncertain and did not clarify whether CXCR2 blockade prevented demyelination or promoted remyelination. Here, we show that the actions of CXCR2 on nonhematopoietic cells unexpectedly delay myelin repair. Bone marrow chimeric mice (Cxcr2(+/-)-->Cxcr2(-/-) and Cxcr2(+/-)-->Cxcr2(+/+)) were subjected to two distinct models of myelin injury. In all cases, myelin repair was more efficient in Cxcr2(+/-)-->Cxcr2(-/-) animals. Oligodendrocyte progenitor cells (OPCs) in demyelinated lesions of Cxcr2(+/-)-->Cxcr2(-/-) mice proliferated earlier and more vigorously than in tissues from Cxcr2(+/-)--> Cxcr2(+/+) animals. In vitro demyelinated CNS slice cultures also showed better myelin repair when CXCR2 was blocked with neutralizing antibodies or was genetically deleted. Our results suggest that CXCR2 inactivation permits optimal spatiotemporal positioning of OPCs in demyelinating lesions to receive local proliferative and differentiating signals. Given that CXCR2 exerts dual functions that promote demyelination and decrease remyelination by actions toward hematopoietic cells and nonhematopoietic cells, respectively, our findings identify CXCR2 as a promising drug target for clinical demyelinating disorders.

Topics: Animals; Animals, Newborn; Antibodies; Bone Marrow; Cell Differentiation; Central Nervous System Stimulants; Cerebellum; Cuprizone; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Flow Cytometry; Freund's Adjuvant; Glycoproteins; In Vitro Techniques; Leukocyte Common Antigens; Lipopolysaccharides; Mice; Mice, Inbred C57BL; Mice, Knockout; Microscopy, Electron, Transmission; Myelin Basic Protein; Myelin Proteolipid Protein; Myelin Sheath; Myelin-Oligodendrocyte Glycoprotein; Nerve Regeneration; Neurologic Examination; Oligodendroglia; Peptide Fragments; Picrotoxin; Proliferating Cell Nuclear Antigen; Receptors, Interleukin-8B; Recovery of Function; Severity of Illness Index; Stem Cells; Time Factors

Human Mesenchymal Stem Cells (MSCs) were previously reported to ameliorate neuronal functional deficits in the MOG35-55-induced experimental autoimmune encephalomyelitis (EAE) mice by inducing T cell anergy. Human Ciliary neurotrophic factor (CNTF) recently was found to promote myelogenesis and reduce inflammation in CNTF-deficient EAE mice. We ectopically overexpressed CNTF in human MSCs to investigate its potential role in promoting remyelination and improving functional recovery in EAE mice. MSCs transfected by Ad-CNTF-IRES-EGFP (MSC-CNTF) were injected intravenously into EAE mice 10 days after the immunization. Neurological functional tests were scored daily by grading clinical signs (score 0-6). Immunofluorescence microscopy was used to detect MSC-CNTF in spinal cord. Expression of NG2, CNTF, and cleaved caspase-3 was measured by immunohistochemistry. CNTF expression was also analyzed by Western blot. Myelin was detected by Solochrome Cyanin staining. Our results found that CNTF concentration in MSC-CNTF cells was 20-fold higher than that in either MSC or Ad-EGFP-transfected MSCs (MSC-EGFP) in vitro. Mice receiving MSC-CNTF cells showed remarkable neuronal functional recovery: the cumulative clinical scores were significantly decreased, and the disease onset was statistically delayed. Mice receiving MSC-CNTF cells showed reduced TNF-alpha, IFN-gamma and increased the level of cytokine IL-10 in peripheral blood and a large number of MSC-CNTF cells were detected in the spleen, but were not detected in other organs such as lung, liver and kidney. In the lesions of these mice, 1) the number of cleaved caspase3-positive cells was significantly reduced; 2) MSC-CNTF- and NG2-positive cells were significantly increased; and 3) the expression of CNTF was dramatically increased. In addition, demyelination was significantly reduced in MSC-CNTF mice. These data indicated that MSC-CNTF may improve functional recovery in EAE mice, possibly by exerting their immunoregulatory activity, inhibiting inflammation, homing MSC-CNTF cells to the lesions, elevating CNTF expression, reducing demyelination, and stimulating oligodendrogenesis.

Topics: Adenoviridae; Amino Acids; Analysis of Variance; Animals; Antigens; Caspase 3; Cell Count; Ciliary Neurotrophic Factor; Cytokines; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Genetic Vectors; Glycoproteins; Green Fluorescent Proteins; Humans; Mesenchymal Stem Cell Transplantation; Mesenchymal Stem Cells; Mice; Mice, Inbred C57BL; Mice, Knockout; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Proteoglycans; Recovery of Function; Statistics, Nonparametric; Time Factors

The IL-21 receptor (IL-21R) consists of a unique subunit and a common gamma chain (gamma(c)) that is shared with other cytokines including IL-2, IL-4, IL-7, and IL-15. The interaction between IL-21 and IL-21R results in significant effects on both innate and adaptive immune responses. In this study we examined the influence of IL-21R deficiency (IL-21R(-/-)) on the development of experimental autoimmune encephalomyelitis (EAE), an animal model of human multiple sclerosis (MS). IL-21R(-/-) mice developed EAE earlier and more severe neurological impairment than control mice, yet those mice could effectively recover from neurological deficits. The impact on EAE initiation by IL-21R deficiency was associated with a defect of CD4(+)CD25(+) T regulatory (Treg) cells and a down-regulated expression of Foxp3. The recovery from IL-21R(-/-) EAE was correlated with an expansion of Treg cells as well as an organ-specific redistribution of NK cells. These results suggest that a temporal influence of IL-21 on the activity of immunoregulatory circuits can be important in the modulation of the course of the autoimmune disease.

Topics: Animals; Antigens, CD; Antigens, Surface; Cell Proliferation; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Female; Flow Cytometry; Gene Expression; Glycoproteins; Interleukin-2; Killer Cells, Natural; Lectins, C-Type; Lymphocyte Activation; Mice; Mice, Knockout; Myelin-Oligodendrocyte Glycoprotein; NK Cell Lectin-Like Receptor Subfamily B; Peptide Fragments; Receptors, Interleukin-21; T-Lymphocytes, Regulatory; Time Factors

The enzyme Fatty Acid Amide Hydrolase (FAAH) is a key regulator of the endogenous levels of a family of biologically active lipid mediators, the fatty acid amides. These include anandamide, oleoyl ethanolamide and palmitoyl ethanolamide, and their effects are mediated by a variety of downstream targets including cannabinoid receptors and peroxisome proliferator-activated receptors (PPARs). Activation of both of these may have anti-inflammatory and neuroprotective effects. Levels of all three mediators are low in normal nervous tissue, but substantially elevated in mice lacking FAAH as a result of genetic deletion. There is a long anecdotal history of cannabis use by patients suffering from multiple sclerosis, and preclinical studies have indicated beneficial effects of cannabinoid receptor stimulation on both long-term outcome and acute muscle spasm in rodent models of multiple sclerosis (experimental autoimmune encephalitis; EAE). Thus far no report has appeared on the effect of inhibition of FAAH on the progression of EAE. Using a chronic mouse EAE model, we present data indicating that mice lacking FAAH experience an initial inflammatory phase of EAE similar in severity to wild type controls, but exhibited a more substantial clinical remission compared to wild type mice.

Topics: Amidohydrolases; Animals; CD3 Complex; Chronic Disease; Demyelinating Diseases; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Glycoproteins; Mice; Mice, Inbred C57BL; Mice, Knockout; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Spinal Cord; T-Lymphocytes; Time Factors

Although demyelination is a cardinal feature in multiple sclerosis, axonal injury also occurs. We tested whether a delay in axonal degeneration could affect the disease severity in two models for multiple sclerosis: experimental autoimmune encephalomyelitis (EAE) and Theiler's murine encephalomyelitis virus (TMEV) infection. We compared wild-type C57BL/6 (B6) mice with C57BL/Wld(s) (Wld) mice, which carry a mutation that delays axonal degeneration. In EAE, both mouse strains were sensitized with myelin oligodendrocyte glycoprotein (MOG)(35-55) peptide and showed a similar disease onset, MOG-specific lymphoproliferative responses, and inflammation during the acute stage of EAE. However, during the chronic stage, B6 mice continued to show paralysis with a greater extent of axonal damage, demyelination, and MOG-specific lymphoproliferative responses compared with Wld mice, which showed complete recovery. In TMEV infection, only Wld mice were paralyzed and had increased inflammation, virus antigen-positive cells, and TMEV-specific lymphoproliferative responses versus infected B6 mice. Because TMEV can use axons to disseminate in the brain, axonal degeneration in B6 mice might be a beneficial mechanism that limits the virus spread, whereas slow axonal degeneration in Wld mice could favor virus spread. Therefore, axonal degeneration plays contrasting roles (beneficial versus detrimental) depending on the initiator driving the disease.

Topics: Animals; Antigens, Viral; Cardiovirus Infections; Demyelinating Diseases; Disease Models, Animal; Disease Progression; Encephalomyelitis, Autoimmune, Experimental; Female; Glycoproteins; Mice; Mice, Inbred C57BL; Multiple Sclerosis; Mutation; Myelin-Oligodendrocyte Glycoprotein; Nerve Degeneration; Peptide Fragments; Species Specificity; Theilovirus; Time Factors

p150/95 (CD11c/CD18, CR4) is a member of the beta(2)-integrin family of adhesion molecules and is considered an important phagocytic receptor. The role of p150/95 in the development of central nervous system demyelinating diseases, including multiple sclerosis, remains unexplored. To determine p150/95-mediated mechanisms in experimental autoimmune encephalomyelitis (EAE), we performed EAE using CD11c-deficient (CD11c(-/-)) mice. EAE in CD11c(-/-) mice was significantly attenuated and characterized by markedly reduced spinal cord T-cell infiltration and interferon-gamma production by these cells. Adoptive transfer of antigen-restimulated T cells from wild-type to CD11c(-/-) mice produced significantly attenuated EAE, whereas transfer of CD11c(-/-) antigen-restimulated T cells to control mice induced a very mild, monophasic EAE. T cells from MOG(35-55) peptide-primed CD11c(-/-) mice displayed an unusual cytokine phenotype with elevated levels of interleukin (IL)-2, IL-4, and IL-12 but reduced levels of interferon-gamma, tumor necrosis factor-alpha, IL-10, IL-17, and transforming growth factor-beta compared with control mice. Overall, CD11c(-/-) T cells from primed mice proliferated comparably to that of control T cells on MOG(35-55) restimulation. Our results indicate that expression of p150/95 is critical on both T cells as well as other leukocytes for the development of demyelinating disease and may represent a novel therapeutic target for multiple sclerosis.

Topics: Animals; Cell Proliferation; Chemokines; Cytokines; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Glycoproteins; Integrin alphaXbeta2; Mice; Mice, Inbred C57BL; Mice, Knockout; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Phenotype; Spinal Cord; T-Lymphocytes

Peroxisome proliferator-activated receptor-gamma is a nuclear receptor transcription factor that regulates cell growth, differentiation and homeostasis. PPARgamma agonists have been used in the treatment of obesity, diabetes, cancer and inflammation. We and others have shown recently that PPARgamma agonists ameliorate experimental allergic encephalomyelitis (EAE), a Th1 cell-mediated autoimmune disease model of multiple sclerosis (MS). We have further shown that PPARgamma agonists inhibit EAE through blocking IL-12 signaling leading to Th1 differentiation and the PPARgamma-deficient heterozygous mice (PPARgamma(+/-)) develop an exacerbated EAE. In this study, we show that in vivo treatment (i.p.) with 100 mug PPARgamma antagonists, Bisphenol A diglycidyl ether (BADGE) or 2-Chloro-5-nitro-N-(4-pyridyl)benzamide (T0070907), on every other day from day 0 to 30, increased the severity and duration of EAE in C57BL/6 wild-type and PPARgamma(+/-) mice. The exacerbation of EAE by PPARgamma antagonists associates with an augmented neural antigen-induced T cell proliferation, IFNgamma production or Th1 differentiation. These results further suggest that PPARgamma is a critical physiological regulator of CNS inflammation and demyelination in EAE.

Topics: Animals; Benzamides; Benzhydryl Compounds; Cell Proliferation; Demyelinating Diseases; Dose-Response Relationship, Immunologic; Drug Administration Schedule; Drug Interactions; Encephalomyelitis, Autoimmune, Experimental; Enzyme-Linked Immunosorbent Assay; Epoxy Compounds; Female; Glycoproteins; Inflammation; Interferon-gamma; Mice; Mice, Inbred C57BL; Mice, Knockout; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; PPAR gamma; Pyridines; Th1 Cells; Thymidine; Time Factors; Tritium

The scavenger receptor that binds phosphatidylserine and oxidized lipoprotein (SR-PSOX)/CXCL16 is a chemokine expressed on macrophages and dendritic cells, while its receptor expresses on T and NK T cells. We investigated the role of SR-PSOX/CXCL16 on acute and adoptive experimental autoimmune encephalomyelitis (EAE), which is Th1-polarized T cell-mediated autoimmune disease of the CNS. Administration of mAb against SR-PSOX/CXCL16 around the primary immunization decreased disease incidence of acute EAE with associated reduced infiltration of mononuclear cells into the CNS. Its administration was also shown to inhibit elevation of serum IFN-gamma level at primary immune response, as well as subsequent generation of Ag-specific T cells. In adoptive transfer EAE, treatment of recipient mice with anti-SR-PSOX/CXCL16 mAb also induced not only decreased clinical disease incidence, but also diminished traffic of mononuclear cells into the CNS. In addition, histopathological analyses showed that clinical development of EAE correlates well with expression of SR-PSOX/CXCL16 in the CNS. All the results show that SR-PSOX/CXCL16 plays important roles in EAE by supporting generation of Ag-specific T cells, as well as recruitment of inflammatory mononuclear cells into the CNS.

Topics: Acute Disease; Adoptive Transfer; Amino Acid Sequence; Animals; Antibodies, Monoclonal; Chemokine CXCL16; Chemokine CXCL6; Chemokines, CXC; Chemotaxis, Leukocyte; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Glycoproteins; Immunization; Inflammation; Lipoproteins, LDL; Membrane Proteins; Mice; Mice, Inbred C57BL; Molecular Sequence Data; Myelin-Oligodendrocyte Glycoprotein; Peptide Fragments; Phosphatidylserines; Receptors, Immunologic; Receptors, Scavenger; Spinal Cord; T-Lymphocyte Subsets

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a nuclear receptor transcription factor that regulates cell growth, differentiation, and homeostasis. PPARgamma agonists are potent therapeutic agents for type 2 diabetes, obesity, and inflammation. Experimental allergic encephalomyelitis (EAE) is a Th1 cell-mediated inflammatory demyelinating autoimmune disease model of multiple sclerosis. We have shown recently that PPARgamma agonists inhibit EAE by blocking IL-12 production, IL-12 signaling, and neural Ag-induced Th1 differentiation. In this study, we show that the PPARgamma-deficient heterozygous mice develop an exacerbated EAE with prolonged clinical symptoms than the wild-type littermates, following immunization with myelin oligodendrocyte glycoprotein (MOG) p35-55 peptide. The exacerbation of EAE in PPARgamma(+/-) mice associates with an increased expansion of CD4(+) and CD8(+) T cells and expression of CD40 and MHC class II molecules in response to MOGp35-55 Ag. The PPARgamma(+/-) mice also showed an increase in T cell proliferation and Th1 response to MOGp35-55 Ag than the wild-type littermates. These findings suggest that PPARgamma be a critical physiological regulator of CNS inflammation and demyelination in EAE and perhaps multiple sclerosis and other Th1 cell-mediated autoimmune diseases.

Topics: Animals; CD40 Antigens; Cell Division; Demyelinating Diseases; Encephalomyelitis, Autoimmune, Experimental; Female; Genetic Carrier Screening; Glycoproteins; Histocompatibility Antigens Class II; Injections, Intramuscular; Interferon-gamma; Interleukin-12; Lymphocyte Activation; Mice; Mice, Inbred C57BL; Mice, Knockout; Myelin-Oligodendrocyte Glycoprotein; Nerve Tissue Proteins; Peptide Fragments; Peroxisomes; Receptors, Cytoplasmic and Nuclear; Severity of Illness Index; Spleen; Th1 Cells; Transcription Factors; Up-Regulation