Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0014070 (encephalomyelitis)
 13,017 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sindbis virus (SV) causes an acute encephalomyelitis in mice. A T cell-dependent inflammatory response is first detected 3 days after infection and includes T cells, B cells, and macrophages. The cytokines produced locally by intrinsic cells of the brain in response to infection and by infiltrating mononuclear cells and their contributions to outcome of infection have not been identified. Semiquantitative reverse transcriptase-PCR was used to evaluate the expression of mRNAs for IL-1 beta, IL-2, IL-4, IL-6, IL-10, TNF-alpha, leukemia inhibitory factor (LIF), and TGF-beta in the brain during fatal and nonfatal SV encephalitis of immunocompetent BALB/cJ and immunodeficient scid/CB17 mice. IL-1 beta and IL-6 mRNAs were detected in uninfected mice before infection and were up-regulated within 24 h. TGF-beta mRNA was also constitutively expressed in uninfected mice. LIF mRNA was occasionally detected in uninfected mice but increased in amounts only in BALB/cJ not scid mice after infection. TNF-alpha, IL-4, and IL-10 mRNAs were not found in uninfected mice but were induced within 24 h and continued to rise through 7 days after infection with substantially higher levels in BALB/cJ than scid mice. These data suggest that intrinsic brain cells produce IL-1, IL-4, IL-6, IL-10, LIF, and TGF-beta mRNAs in response to viral infection. IFN-gamma and IL-2 mRNAs were detected only in BALB/cJ mice and not until 3 days after infection with the initiation of inflammation. IL-4 and IL-10 mRNAs were more persistent and more easily detectable than IL-2 and IFN-gamma mRNAs. These data suggest a predominant type 2 cytokine response in the brain during SV encephalitis. BALB/cJ mice infected with a neurovirulent strain of SV (NSV), had 100% mortality, whereas NSV-infected scid mice developed persistent nonfatal infection. Inflammation was more intense in NSV-infected mice, however, no substantial differences in cytokine mRNA levels were detected when compared with mice with nonfatal SV infection suggesting that the cytokines measured do not in and of themselves lead to fatal central nervous system disease.
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PMID:Intracerebral cytokine mRNA expression during fatal and nonfatal alphavirus encephalitis suggests a predominant type 2 T cell response. 830 Nov 32

Theiler's murine encephalomyelitis virus (TMEV) produces a chronic, inflammatory demyelinating disease in susceptible mouse strains that is used as a model for multiple sclerosis. Because disease susceptibility correlates temporally with the development of virus-specific delayed-type hypersensitivity (DTH) responses, we studied methods and mechanisms by which virus-specific DTH could be specifically inhibited. The intravenous injection of UV-inactivated TMEV coupled to syngeneic splenocytes via a carbodiimide linkage (TMEV-SP), prior to immunization, induced a significant degree of tolerance in virus-specific helper (Th) cells as determined by decreased DTH and T cell proliferative responses, and decreased interleukin (IL)-2 and interferon (IFN)-gamma protein and mRNA levels. In contrast to the reduced levels of Th1-specific lymphokine mRNA levels, IL-4-specific mRNA levels in response to virus stimulation were not affected in tolerant mice. Surprisingly, the total anti-TMEV antibody response in DTH tolerant mice was enhanced 20-100-fold over sham-tolerized controls and was composed of reduced levels of anti-virus IgG2a, but dramatically increased levels of anti-virus IgG1. The "split-tolerance" was antigen specific, dependent on the concentrations of TMEV and carbodiimide used in the coupling procedure, and varied with the number of coupled syngeneic splenocytes administered. The fixative effects of carbodiimide on antigen-presenting function were necessary for the induction of DTH tolerance with TMEV-SP, since intravenous administration of virus coupled to splenocytes via a biotin-avidin linkage led to enhanced virus-specific antibody responses, but was unable to inhibit DTH unless concomitantly fixed with carbodiimide. Collectively, the data indicate that Th1 cells (mediating DTH, IL-2 and IFN-gamma production, and helper function for IgG2a production) were specifically anergized, with concomitant stimulation of Th2 cells (producing IL-4 and mediating helper function for IgG1 antibody production).
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PMID:Split tolerance of Th1 and Th2 cells in tolerance to Theiler's murine encephalomyelitis virus. 841 86

Oral administration of acetylcholine receptor (AChR) or myelin basic protein (MBP) to Lewis rat prior to immunization with AChr or MBP and complete Freund's adjuvant (CFA) has previously been shown to prevent or delay the onset of experimental autoimmune myasthenia gravis (EAMG) or experimental allergic encephalomyelitis (EAE), which represent animal models of myasthenia gravis and multiple sclerosis, respectively. Here we show that Lewis rats immunized with AChr+MBP+CFA developed both signs of muscular weakness seen in EAMG and paresis characteristic for EAE. This disease was associated with high levels of anti-AChR and anti-MBP antibody secreting cells and of AChR- and MBP-reactive INF-gamma secreting Th1-like cells in lymph nodes. The diseased rats also showed upregulation of AChR- and MBP-induced mRNA expression of IFN-gamma in lymph node cells. Oral tolerization with AChR and MBP in combination prior to immunization with AChR+MBP+CFA alleviated clinical disease as well as AChR- and MBP-specific B cell node cells. The results implicate that oral tolerization simultaneously to more than one autoimmune disease-related autoantigen is feasible, and that suppression of autoantigen-induced IFN-gamma and augmentation of TGF-beta are pivotal in tolerance induction.
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PMID:Suppression of experimental autoimmune myasthenia gravis and experimental allergic encephalomyelitis by oral administration of acetylcholine receptor and myelin basic protein: double tolerance. 855 28

The effect of orally administered type 1 interferons on the severity of acute experimental autoimmune encephalomyelitis (EAE), a T cell-mediated autoimmune disease, was examined by inoculation of Lewis rats with guinea pig myelin basic protein (GPMBP) and complete Freund's adjuvant. Rats were fed either rat species-specific or human recombinant type 1 interferon (IFN) or mock IFN daily for 7 days preceding immunization and for 21 days thereafter. There was a significant decrease in the clinical score and inflammatory foci in animals fed 5000 units IFN compared with mock-treated animals. There was a significant decrease in clinical score and number of inflammatory foci in spinal cord in animals fed orally 5000 units human recombinant IFN-alpha PO compared with SC 5000 units recombinant human IFN-alpha. Oral administration of type 1 interferon, as opposed to subcutaneous administration, inhibited the secretion of IFN-gamma from ConA-activated draining popliteal lymph node cells compared with mock-fed animals. These experiments demonstrate that acute EAE is more effectively inhibited by equivalent amounts of orally in contrast to parenterally administered IFN-alpha. These results suggest that type 1 IFNs are active by the oral route and have significant clinical and histologic effects in acute autoimmune disease.
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PMID:Modification of acute experimental autoimmune encephalomyelitis in the Lewis rat by oral administration of type 1 interferons. 859 Mar 14

Experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis, is an autoimmune disorder seen in mice and rats following immunization with myelin basic protein (MBP) or MBP-derived peptides. IFN-gamma, a cytokine produced by a variety of cells, is involved in many inflammatory and immune regulatory events. Contradictory results concerning exacerbations and the disease course were seen comparing injections of IFN-gamma in humans suffering from multiple sclerosis to studies using anti-IFN-gamma Abs in mice with EAE. To study the role of IFN-gamma and IFN-gamma-producing cells in EAE, we crossed IFN-gamma knockout mice (H-2b) (unable to produce IFN-gamma due to the disruption of the IFN-gamma gene) with an EAE-susceptible mouse strain, B10.PL (H-2u). EAE was seen in IFN-gamma knockout mice, heterozygotic (IFN-gamma +/-) mice, as well as wild-type littermates following immunization with MBP. Histologic analyses of the central nervous system of IFN-gamma knockout mice with EAE revealed massive infiltrates composed of lymphocytes, macrophages, and granulocytes. We conclude that the presence of IFN-gamma is not crucial to the induction or the clinical course of EAE.
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PMID:Mice with a disrupted IFN-gamma gene are susceptible to the induction of experimental autoimmune encephalomyelitis (EAE). 859 93

Nitric oxide (NO) is a critical mediator of a variety of biological functions. A range of micro-organisms, including viruses, bacteria, protozoa and helminths, is sensitive to NO produced by macrophages activated with gamma-interferon (IFN-gamma) and lipopolysaccharide. In contrast, NO is involved in a number of important immunopathologies, including diabetes, graft-vs-host reaction, rheumatoid arthritis, systemic lupus erythematosus, experimental autoimmune encephalomyelitis and multiple sclerosis. Thus, it is crucial that the synthesis of NO is under tight regulation. This is achieved, in part, through the opposing cytokines produced by T helper 1 (Th1) and Th2 cells. Th1 cells produce IFN-gamma, which is the most powerful inducer of inducible NO synthase (iNOS). In contrast, interleukin 4 is produced by Th2 cells and inhibits the induction of iNOS at the level of transcription. Furthermore, NO is also produced by Th1 cells, whose proliferation can be inhibited by high concentrations of NO. Thus, apart from being a mediator of Th1/Th2 interaction, NO may also be an important self-regulatory molecule that prevents the over-expansion of Th1 cells which are implicated in a range of severe immunopathologies.
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PMID:Nitric oxide in infectious and autoimmune diseases. 872 41

It is now currently thought that Th1 autoreactive cells may induce organ specific autoimmune disease and in these situations Th2 cells are considered as regulatory cells. However, in other situations Th2 cells may be pathogenic. Thus, some chemicals (HgCl2, gold salts or D-penicillamine) may induce Th2-mediated systemic autoimmune disorders in susceptible Brown-Norway (BN) rats. In contrast, HgCl2 induces non antigen specific immunosuppression in Lewis (LEW) rats and protects this strain against organ-specific autoimmune diseases such as experimental autoimmune encephalomyelitis (EAE). Anti-self MHC class II T cells have been detected in both susceptible and resistant strains upon exposure with these chemicals. Autoreactive T cell lines that recognize self MHC class II molecules have been derived from gold salt-injected BN rats (BNAu lines) and from HgCl2-injected LEW rats (LEWHg lines). BNAu T cell lines produced IL-4 and transferred antibody-mediated autoimmunity in BN rats deprived of CD8+ cells. In contrast, HgCl2 protects susceptible rats from Th1-mediated autoimmunity, (autoimmune uveoretinitis). LEWHg lines produced IL-2, IFN-gamma and TGF-beta and were able to protect LEW rats against cell-mediated autoimmunity (EAE) and (LEW x BN)F1 hybrids from antibody-mediated, HgCl2-induced autoimmunity. Several points will be discussed: the specificity of these autoreactive T cells, the mechanisms by which chemicals may induce these cells and the mechanisms by which the immune system maintains or reestablishes self tolerance in rats exposed to these agents.
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PMID:Th2 and Th1 autoreactive anti-class II cell lines in the rat suppress or induce autoimmunity. 873 66

The B7 family of cell surface molecules expressed on APC provides accessory signals to T cells via either CD28 or CTLA-4. However, while CD28 transduces a costimulatory signal that is required for an optimal immune response, CTLA-4 transmits a negative signal. These studies use an anti-CTLA-4 mAb to directly address the role of this T cell surface molecule in experimental allergic encephalomyelitis (EAE). CTLA-4 regulation of disease was assessed during initial immune cell interactions and during the effector stage of the encephalitogenic immune response. The effects of anti-CTLA-4 treatment were schedule dependent. CTLA-4 blockade during the onset of clinical symptoms markedly exacerbated disease, enhancing mortality. Disease exacerbation was associated with enhanced production of the encephalitogenic cytokines TNF-alpha, IFN-gamma and IL-2. Hence, CTLA-4 regulates the intensity of the autoimmune response in EAE, attenuating inflammatory cytokine production and clinical disease manifestations.
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PMID:CTLA-4 blockade enhances clinical disease and cytokine production during experimental allergic encephalomyelitis. 875 11

In experimental allergic encephalomyelitis (EAE), T cells infiltrate the central nervous system (CNS) and induce inflammation. These CD4+ T cells secrete interferon (IFN)-gamma, levels of which correlate with disease severity, and which is proposed to play a key role in disease induction. Many strains of mice are resistant to EAE. We have studied the effect of deletion of IFN-gamma on the ability to induce EAE in resistant BALB/c-backcrossed mice. As expected, only 0-6% of BALB/c or BALB/c-backcrossed mice developed EAE when immunized with myelin basic protein in adjuvant. Strikingly, abrogation of IFN-gamma expression by targeted disruption of the IFN-gamma gene (GKO mice) converted them to a susceptible phenotype. As many as 71% of these IFN-gamma-deficient mice developed EAE, a frequency comparable to that seen with the susceptible SJL/J strain. In addition, EAE was of unusually high severity in mice lacking IFN-gamma. Immunological characteristics of disease in IFN-gamma-deficient mice were comparable to those seen in susceptible (SJL/J) mice with EAE, including perivascular infiltration in the CNS and order-of-magnitude increases for both CD3 gamma chain and TNF-alpha mRNA levels in the spinal cord. We thus demonstrate that lack of IFN-gamma converts an otherwise EAE-resistant mouse strain to become susceptible to disease. Therefore, in BALB/c mice, IFN-gamma confers resistance to EAE.
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PMID:Interferon-gamma confers resistance to experimental allergic encephalomyelitis. 876 73

Constitutive expression of the cellular proto-oncogenes c-fos and c-jun, and in a lesser extent ras, was demonstrated in the glioma cell line C-6 by flow cytometry analysis using specific mono and polyclonal antibodies. Basal expression of the products of the early response genes c-fos and c-jun were increased 66 and 50% when Theiler's murine encephalomyelitis virus (TMEV) infected these cells. No increase in ras transcription could be demonstrated after infection. This activation follows a kinetic reaching maximum values after 60 min and was proportional to the multiplicity of infection used. The described effect was completely abrogated by rabbit antibodies to TMEV but was not altered by normal rabbit serum. Furthermore, an intact infectious virion is needed to detect this effect. Fetal calf serum and lipopolysaccharide stimulation slightly increases c-fos and c-jun expression following a slower kinetics. Cytokine treatment (IL-1 alpha, IL-6, IFN-gamma and TNF alpha), did not induce oncogene over-expression. Therefore, this stimulation seems to be linked to the TMEV infectious process.
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PMID:Overexpression of basal c-fos and c-jun but not of ras oncogenes after Theiler's murine encephalomyelitis virus infection of glial cells. 879 9


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