Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004364 (autoimmune disease)
 24,845 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effects of neuroantigen-specific tolerance on the induction and effector stages of relapsing experimental autoimmune encephalomyelitis (R-EAE) were examined. The incidence of clinical and histologic signs of active MSCH-induced R-EAE, and accompanying neuroantigen-specific DTH responses, were dramatically reduced in SJL/J mice tolerized via the i.v. injection of syngeneic splenocytes coupled with MSCH, PLP, or encephalitogenic PLP peptides 7-14 days before priming. MBP-specific tolerance was not effective in preventing active R-EAE. In contrast to MSCH-induced active R-EAE, treatment of recipient mice with splenocytes coupled with MBP and the encephalitogenic MBP 84-104 peptide, but not with PLP, suppressed of clinical signs of adoptive R-EAE mediated by MBP-specific effector T cells in a dose-dependent manner. Neuroantigen-coupled splenocytes were also efficient in treating established disease as tolerization of SJL/J mice after the first incidence of clinical disease significantly reduced the incidence and severity of subsequent paralytic relapses. Antigen-specific tolerance thus provides a powerful approach for the prevention and/or treatment of autoimmune disease.
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PMID:Specific immunoregulation of the induction and effector stages of relapsing EAE via neuroantigen-specific tolerance induction. 172 64

The immunopathogenesis of MS is discussed in the light of data recently obtained in Experimental Autoimmune Encephalomyelitis (EAE), a myelin specific experimental autoimmune disease reflecting the first, inflammatory phase of MS plaque generation. EAE is caused by CD4+ T cells specific for defined myelin protein, like MBP and PLP. In rats and mice there is a marked dominance of the autoantigenic peptide epitopes on the one hand, and the T cell receptor V regions on the other. During T cell mediated EAE, clonotypically counterregulatory CD8+ T cells are induced, which specifically neutralize the encephalitogenic T clones.
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PMID:Immunopathogenesis of multiple sclerosis. 189 86

Different models of experimental autoimmune encephalomyelitis (EAE) have been successfully applied to investigate and manifold aspects of the autoimmune pathogenesis of multiple sclerosis. Studies using myelin-specific T-cell lines that transfer EAE to naive recipient animals established that only activated lymphocytes are able to cross the endothelial blood-brain barrier and cause autoimmune disease within the local parenchyma. All encephalitogenic T cells are CD4+ Th1-type lymphocytes that recognize autoantigenic peptides in the context of MHC class II molecules. In the case of myelin basic protein (MBP) specific EAE in the Lewis rat, the T-cell response is directed against one strongly dominant peptide epitope. The encephalitogenic T cells preferentially use one particular set of T-cell receptor genes. Although MBP is a strong encephalitogen in many species, a number of other brain protein are now known to induce EAE. These include mainly myelin components (PLP, MAG, and MOG), but also, the astroglial S-100 beta protein. Encephalitogenic T cells produce only inflammatory changes in the central nervous system, without extensive primary demyelination. Destruction of myelin and oligodendrocytes in these models requires additional effector mechanisms such as auto-antibodies binding to myelin surface antigens such as the myelin-oligodendrocyte glycoprotein.
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PMID:Animal models. 751 26

Multiple sclerosis is assumed to be an autoimmune disease mediated by T cells specific for myelin protein, such as, myelin basic protein (MBP) and PLP. Several groups reported that PLP-specific T cells are activated in the cerebrospinal fluid and, to a lesser extent, in the peripheral blood of the patients. We identified seven T cell epitopes within PLP residue 85-159. The T cell responses to these epitopes were higher in MS than in healthy subjects. PLP 95-116 and 105-124 specific T cells were more frequently established from DR2 MS than from non-DR2 MS, indicating that the DR2 restricted T cells recognizing these determinants are involved in the pathogenesis of MS. It is found PLP-specific T cells preferentially use V beta 5 and V beta 2 families though the usage is not exclusive. TCR beta chain complementary determining region 3 (CDR3) amino acid motifs of some PLP-specific T cells were homologous to those of MS lesion T cells, so it is likely that PLP-specific T cells infiltrate MS lesions. To our surprise, the CDR3 motifs of PLP-specific clones resemble those of MBP-specific clones. According to these facts, some antigen-independent pressure might give a common structure to T cells involved in MS.
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PMID:[T cell immunity to proteolipid protein (PLP) in multiple sclerosis (MS): identification of DR2-associated PLP determinants and conserved TCR CDR3 motifs]. 752 67

CD4+ T cells specific for PLP 139-151 induce a relapsing-remitting form of EAE which is similar to the human demyelinating disease multiple sclerosis (MS) in both clinical course and histopathology. Conservative and nonconservative amino acid substitutions were introduced at three TcR or MHC contact residues within PLP 139-151 to identify fine specificity requirements, at the polyclonal level, for stimulating naive encephalitogenic T cells and for reactivating pre-primed autoreactive T cells as measured by T cell proliferation, cytokine induction, and functional encephalitogenic potential. The results indicate that peptides with substitutions at position 145 exhibited a significantly diminished ability to induce active disease, but these substitutions had little or no effect on the ability to activate PLP 139-151-primed T cells for proliferation or disease transfer. A conservative or a nonconservative substitution at position 144 ablated both encephalitogenic potential in active and adoptive EAE models and the ability to induce proliferative responses in T cells primed to the native peptide. A nonconservative lysine for glycine, but not a conservative serine substitution, at position 146 had similar effects. In contrast to their inability to induce active EAE and stimulate in vitro proliferation of PLP 139-151-primed T cells, the Y144 and the 146 analog peptides were able to suboptimally reactivate these cells for transfer of adoptive EAE. Furthermore, the nonencephalitogenic K146 peptide was found to exacerbate in vivo induction of EAE induced by priming with a suboptimal dose of PLP 139-151. These data support the hypothesis that naive neuroantigen-specific CD4+ T cells have more stringent activation requirements than do PLP 139-151-specific T cells which have previously encountered antigen. The finding that the analog peptides induced differential patterns of cytokine production, with LT/TNF-alpha production but not IFN-gamma production correlating with full encephalitogenic potential, suggests different functional outcomes may result from differential levels of signal transduction triggered by the substituted peptides. The significance of these results to the potential development of autoimmune disease via molecular mimicry and for the development of new strategies for preventing and treating T cell-mediated autoimmune diseases is discussed.
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PMID:Differential recognition of peptide analogs by naive verses activated PLP 139-151-specific CD4+ T cells. 754 8

Multiple sclerosis is a presumed autoimmune disease, associated with inflammation in the CNS white matter, mediated by autoreactive T cells. We previously reported that oral myelin tolerization of relapsing-remitting MS patients resulted in fewer attacks, as compared to a placebo-fed group. Here, we examined whether oral tolerization with bovine myelin resulted in altered autoreactive T-cell populations or altered T-cell fraction. We generated 4,620 T-cell lines from 34 relapsing-remitting MS patients (17 were fed bovine myelin daily), and each line was examined for proliferation to MBP, PLP, and TT and for secretion of IL-4, IFN-gamma, and TGF-beta1. The frequency of TGF-beta1-secreting T-cell lines after MBP and PLP stimulation in fed patients was greater than that of nonfed patients. These experiments demonstrate that oral tolerization with autoantigen results in altered cytokine secretion in a human autoimmune disease with the generation of TGF-beta1-secreting T cells that may regulate the inflammatory response at the site of the demyelinating lesions in multiple sclerosis. These data provide the first evidence of antigen-specific modification of cytokine secretion in a human autoimmune disease.
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PMID:Antigen-specific TGF-beta1 secretion with bovine myelin oral tolerization in multiple sclerosis. 861 Sep 78

In the present study we address the question of whether distinct self-determinants can target alternative autoimmune disease patterns in experimental autoimmune encephalomyelitis (EAE), an animal model widely used for studying multiple sclerosis. We have found that the clinical course of EAE can be determined by the target peptide selected for induction of disease. In SJL/J mice, actively induced and passively transferred EAE mediated by the immunodominant PLP determinants p139-151 and p178-191 consistently produced a rapid onset of severe clinical signs. In contrast, a delayed onset of both active and passive EAE is associated with the nondominant cryptic PLP determinant p104-117. The delayed disease induced with p104-117 is not associated with any unusual peptide feature, with bystander immunoregulation, with inept class II MHC binding, or with failure to induce T cell expression of CD44, VLA-4, or IL-2 receptor upon activation. However, delayed disease is associated with innate qualities of the T cell repertoire responding to the p104-117 determinant. T cell lines responding to the cryptic p104-117 show limited TCR-V beta utilization compared to the diverse repertoire responding to the dominant p139-151 determinant. The repertoire deletions are accompanied by low level production of pathogenic Th1 cytokines (IFN gamma; IL-2) and increased production of regulatory Th2 (IL-4) cytokine in activated p104-117 primed T cells. Thus, the delayed encephalitogenicity of p104-117 may be due to TCR-V beta deletions and activation defects in the responding T cell repertoire. The development of "slow disease" mediated by autoreactivity against hidden self-determinants may have important implications in the pathogenesis of both relapsing and chronic autoimmune demyelinating disease.
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PMID:Determinant-regulated onset of experimental autoimmune encephalomyelitis: distinct epitopes of myelin proteolipid protein mediate either acute or delayed disease in SJL/J mice. 882 78

Chronic progression of autoimmune disease is accompanied by the acquisition of autoreactivity to new self-determinants. Recent evidence indicates that this process, commonly referred to as determinant spreading, may be pathogenic for chronicity. Our studies on experimental autoimmune encephalomyelitis (EAE), a murine model widely used in multiple sclerosis (MS) studies, have shown that determinant spreading develops as a predictable sequential cascade of neo-autoimmunity during progression to chronic disease. By 7-8 weeks after immunization of (SWR x SJL)F1 mice with the immunodominant myelin proteolipid protein determinant (PLP 139-151), splenocytes consistently respond to the immunodominant myelin basic protein determinant (MBP 87-99). In the present study, we directly address the pathogenicity of neo-autoimmunity resulting from endogenous self-priming during the course of disease. Our results indicate that T cells responding to the spreading MBP 87-99 determinant produce a proinflammatory cytokine profile consistent with type 1 helper T cells (Th1) cells. In addition, splenocytes activated to the spreading MBP 87-99 determinant consistently transfer acute EAE in naive recipients even when T cells reactive to the priming PLP 139-151 immunogen are eliminated by bromodeoxyuridine (BUdR)-mediated photolysis. Our data indicate that endogenous neo-autoantigen priming during chronic autoimmune disease generates type 1 helper T cells (Th1) cells that are autonomously pathogenic. These results provide further evidence supporting the view that determinant spreading is a pathogenic process that leads to chronic progression of autoimmune disease.
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PMID:Generation of autonomously pathogenic neo-autoreactive Th1 cells during the development of the determinant spreading cascade in murine autoimmune encephalomyelitis. 887 7

We have evaluated the effects of rmIL-12 on the course of adoptively transferred EAE. When mice were injected with LNC that had been stimulated in vitro with PLP in the presence of rmIL-12, the subsequent course of disease was more severe and prolonged than controls. In vitro stimulation with PLP in the presence of IL-12 was associated with an increase in IFN-gamma and decrease in IL-4-producing cells, indicating a preferential expansion of Th1 effector cells. At peak disease, no notable differences in either the cellular composition or cytokine expression within CNS lesions was seen between groups. However, the frequency of macrophages that stained positively for inducible nitric oxide synthase (iNOS) was increased in animals challenged with rmIL-12 treated LNC. These data suggest that in addition to promoting the preferential expansion of IFN-gamma-producing cells by rmIL-12 treatment in vitro, in vivo effects leading to macrophage activation and iNOS expression may contribute to the severe, protracted course of CNS inflammation in this model. In contrast, treatment of mice with an antibody to murine IL-12 following cell transfer completely prevented paralysis with only 40% of the mice developing mild disease. These data suggest that endogenous IL-12 plays a pivotal role in the pathogenesis of this model of autoimmune disease.
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PMID:Regulation of experimental autoimmune encephalomyelitis by interleukin-12. 895 33

Myelin proteins had been thought to be sequestered behind the blood-brain barrier. Recently, however, myelin proteins have been found to be expressed in lymphoid tissues. The myelin basic protein (MBP) gene is embedded within a larger transcription unit called the golli-MBP gene. This larger gene encodes both the "classic" MBPs as well as the structurally related golli-MBPs. In this study, golli-MBP expression in lymph nodes was examined in four different models of relapsing experimental autoimmune encephalomyelitis (rEAE). Disease in these rEAE models was induced by the adoptive transfer of T lymphocytes specific for 18.5-kDa MBP, MBP peptide 83-102, or PLP peptide 139-151 in the SJL/J mouse and the adoptive transfer of T lymphocytes specific for MBP peptide Ac1-9 in the (SJL/J x PL/J)F1 mouse. In all four models, expression of golli-MBP BG21 mRNA was increased two- to fivefold in lymph nodes of mice 45 to 60 days post-transfer. Immunohistochemical analysis indicated that expression occurred principally in macrophages within lymph nodes. Endogenous golli-MBP epitopes within lymph node cells stimulated "classic" MBP 1-44-specific T lymphocytes, and this stimulatory ability resided within the adherent lymph node cell population. An increase in myelin protein expression within lymph nodes during rEAE has implications with regard to intra- and intermolecular epitope spreading. This is the first report describing an increase in target autoantigen expression within lymphoid tissue during an autoimmune disease.
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PMID:Myelin protein expression is increased in lymph nodes of mice with relapsing experimental autoimmune encephalomyelitis. 937 62


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