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)

A combined role of a virus infection of the central nervous system (CNS) and an autoimmune response to myelin basic protein (MBP), an autoantigen of the CNS, is suggested in the pathogenesis of multiple sclerosis (MS). SJL mice are highly susceptible while B6 mice are less susceptible to the induction of experimental autoimmune encephalomyelitis (EAE), the autoimmune model of MS. Peripheral inoculation of Semliki forest virus (SFV) into SJL and B6 mice resulted in: (1) Higher viral titers, more severe clinical disease, and hence a stronger nonspecific and SFV-specific lymphoproliferation, and production of IFN-gamma and TNF/LT was observed by splenocytes (SPL) of B6 than by those of SJL mice, on Day 7 postinfection. (2) Following viral clearance, however, proliferation to SFV, and to MBP, and the production of IFN-gamma and TNF/LT by SPL of SFV-infected SJL mice were significantly higher, while the production of TGF-beta was significantly lower than by those of B6 mice. In conclusion, the immune responses to SFV, and to MBP, which were triggered by SFV infection were significantly higher and more prolonged in the SPL of SJL mice, the EAE-susceptible mice, than by those of B6 mice after the infection was cleared.
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PMID:Immune responses, and autoimmune outcome, during virus infection of the central nervous system. 751 51

We have investigated the T cell receptor (TCR) repertoire in the inflammatory infiltrates of T line-transferred experimental autoimmune encephalomyelitis (EAE) of the Lewis rats. Using a panel of TCR V beta-specific monoclonal antibodies (mAbs) and immunocytochemistry, we studied the nature of the T cells entering the central nervous system (CNS) after transfer of either myelin basic protein (MBP)-reactive, or MBP-reactive but non-encephalitogenic T cell lines. All the MBP-specific T cell lines predominantly used the V beta 8.2 TCR chain. T cell lines specific for the tuberculin purified protein derivative (PPD), using TCR V genes different from V beta 8.2, served as controls. We first studied the time course of T cells entering the CNS. In all recipient rats, small, but significant numbers of alpha beta-TCR-expressing infiltrate cells appeared in the CNS within the first 24 h after T cell transfer. In animals injected with either type of MBP-reactive T cells, the early infiltrate cells were preferentially located within the parenchyma of the spinal cord, while in PDD T line-injected rats, the lymphocytes were mostly found in the meninges. TCR V beta gene usage was examined on the peak of clinical disease. Six days after T cell transfer, the TCR repertoire used by infiltrating lymphocytes in general seemed to be highly diverse. None of the V beta isotypes examined (i.e. V beta 8.2, V beta 8.5 or V beta 10) was used by a major population of the alpha beta-TCR-positive T cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The inflammatory lesion of T cell line transferred experimental autoimmune encephalomyelitis of the Lewis rat: distinct nature of parenchymal and perivascular infiltrates. 752 Feb 6

Oral administration of myelin basic protein (MBP) is an effective means of suppressing experimental autoimmune encephalomyelitis (EAE). In the Lewis rat model, we have previously shown that this effect is mediated by active suppression as T lymphocytes from animals orally tolerized to MBP suppress in vitro immune responses and in vivo adoptively transfer disease protection to naive recipients. This effect is mediated by the cytokine TGF-beta which is secreted by T cells from orally tolerized animals after being triggered by the oral tolerogen. In the present study we investigated Peyer's patches in SJL mice following orally administered MBP. Peyer's patches are one of the major lymphoid structures of gut-associated lymphoid tissue, and a site thought to play an important role in the induction of oral tolerance. Twenty-four hours after one feeding of 1 mg of MBP, there were no proliferative responses to MBP in Peyer's patches. However, when Peyer's patches from MBP-fed animals were stimulated with IL-2 in the presence of MBP, reduced proliferation to IL-2 was observed, and this inhibition was reversed with anti-TGF-beta antibody. Suppression of IL-2-induced proliferation by MBP was not observed in unfed animals or if Peyer's patches from MBP-fed animals were stimulated with a control antigen (ovalbumin). Stimulation of Peyer's patches T cells from MBP-fed animals with MBP resulted in secretion of TGF-beta in a dose-related fashion with less TGF-beta secretion at higher doses. Furthermore, cells from Peyer's patches of animals fed MBP adoptively transferred protection to actively induced EAE. Thus, MBP-specific TGF-beta-secreting regulatory cells recovered from Peyer's patches after a single oral administration of MBP are not evident as measured by proliferation, but are capable of suppressing in vitro and in vivo cell-mediated immune responses. Peyer's patches appear to be an important site for the induction of cells which mediate the active suppression component of oral tolerance.
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PMID:Oral tolerance to myelin basic protein induces regulatory TGF-beta-secreting T cells in Peyer's patches of SJL mice. 752 Aug 38

Experimental autoimmune encephalomyelitis (EAE) is influenced by polymorphism of the MHC. We have previously found that Lewis rats with certain MHC haplotypes are susceptible to disease induced with the myelin basic protein (MBP) peptide 63-88, whereas Lewis rats with other MHC haplotypes are resistant. Interestingly, rats with the MHC u haplotype develop an immune response to the MBP 63-88, but do not get EAE. In this study we have used intra-MHC recombinant rat strains to compare the influences of the MHC u with the a haplotype. We discovered the following: 1) The class II region of the MHC a haplotype permits EAE and a Th1 type of immune response as measured by IFN-gamma production after in vitro challenge of in vivo-primed T cells with MBP 63-88. 2) The class II region of the u haplotype is associated with a disease-protective immune response characterized by production of not only IFN-gamma, but also of IL-4 mRNA expression by the MBP 63-88-activated cells. 3) The class I region upstream of the class II region of the u haplotype is associated with a disease-protective effect and the expression of mRNA for TGF-beta after MBP 63-88-induced activation. Thus, such a TGF-beta response occurs in all strains expressing the class I Au allele. Treatment with Abs to CD8+ cells abrogates peptide-induced TGF-beta mRNA expression, and aggravates disease in strains with the class I Au allele.
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PMID:Protective influences on experimental autoimmune encephalomyelitis by MHC class I and class II alleles. 752 59

We have previously shown that orally administered myelin basic protein (MBP) suppresses experimental autoimmune encephalomyelitis in both the Lewis rat and the SJL mouse. In the Lewis rat fed low doses of MBP, we found that protection can be adoptively transferred by CD8+ cells and that these cells inhibit immune responses via the secretion of TGF-beta after Ag-specific triggering. In the present study, we investigated the cellular requirements for the generation of active suppression following oral administration of MBP in SJL and (PLJ x SJL)F1 mice. We first determined the frequency of MBP cells secreting Th1 (IFN-gamma) and Th2 (IL-4/IL-10) cytokines or TGF-beta after oral administration of MBP. We found that in SJL mice, orally administered MBP (0.5 mg/feeding) led to an increased frequency of TGF-beta-, IL-4-, and IL-10-secreting cells and a decreased frequency of IFN-gamma-producing cells. This pattern was observed in both CD4+ and CD8+ populations; adoptive transfer of either CD4+ or CD8+ cells from orally tolerized mice suppressed autoimmune encephalomyelitis in recipient animals. We then studied the role of CD8+ cells on the generation of oral tolerance to MBP by depleting CD8+ cells in vivo with anti-CD8 mAb. Oral tolerance was successfully induced in such animals, as demonstrated by a decrease in clinical disease and T cell proliferative responses, although there was less TGF-beta production in vitro and less disease protection on days 20 to 22 in CD8-depleted animals. These studies demonstrate that CD4+ cells in the absence of CD8+ cells can mediate the active suppression component of oral tolerance in mice and that there is a reciprocal relationship between Th1- and Th2-type cytokine production associated with oral tolerization.
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PMID:Induction of oral tolerance to myelin basic protein in CD8-depleted mice: both CD4+ and CD8+ cells mediate active suppression. 754 26

Migration of leukocytes through an in vitro, cell culture model of the blood-brain barrier (BBB) composed of murine brain microvessel endothelial (En) cells and astrocytes, and in vivo in experimental allergic encephalomyelitis (EAE), was investigated. We have recently shown that the adhesiveness of cultured murine brain microvascular endothelial cells for lymphocytes can be increased significantly by pretreatment with IL-1 beta, TNF-alpha, IFN-gamma, and LPS. In the present study, we investigated the role of TGF-beta 2 on the migration of leukocytes through the BBB. In vitro migration was assessed by measuring the percentage of 51Cr-labeled leukocytes migrating through the En/astrocyte monolayers. The basal level of migration was up-regulated significantly by treating the En/astrocyte monolayers with IL-1 alpha, IFN-gamma, TNF-alpha, and LPS. The ability of these cytokines to modulate migration was dose-dependent. Treatment of En cell/astrocyte monolayers with TGF-beta 2 down-regulated the level of leukocyte migration up-regulated by IL-1 alpha, IFN-gamma, and TNF-alpha in vitro in a dose-dependent manner. TGF-beta 2 also inhibited the migration of lymphocytes into the central nervous system (CNS) in vivo in a dose-dependent fashion. Taken together, these findings strongly suggest that TGF-beta plays an important role in the reduction of lymphocyte infiltration into the CNS in inflammatory demyelinating diseases such as EAE.
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PMID:TGF-beta 2 decreases migration of lymphocytes in vitro and homing of cells into the central nervous system in vivo. 760 8

It had been demonstrated previously that the administration of transforming growth factor-beta 1 (TGF-beta 1) reduced the clinical severity of experimental allergic encephalomyelitis (EAE). Treatment with the related immunosuppressive molecule, TGF-beta 2, resulted in similar inhibition of T cell activation and proliferation in vitro. Long-term treatment was effective in reducing clinical severity of EAE and the number of relapses in mice receiving either myelin basic protein- or peptide-91-103-specific T cell lines. When examined histologically, mice that had received TGF-beta 2 demonstrated significantly less inflammation and demyelination in the central nervous system. Examination of other organs demonstrated no pathology or deleterious side effects from long-term TGF-beta 2 therapy. These findings have relevance for the use of TGF-beta 2 as a therapeutic agent for the human demyelinating disease, multiple sclerosis.
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PMID:Long-term treatment of chronic relapsing experimental allergic encephalomyelitis by transforming growth factor-beta 2. 768 86

Resistance to experimental allergic encephalomyelitis (EAE) induction by homogenized myelin (MSCH) in complete Freund's adjuvant (CFA) and pertussigen (P) in SJL mice was seen 1 week after intravenous injection of PLP 139-151 coupled to spleen cells (PLP-ECDI-SP). Although this resistance could be transferred by spleen cells enriched for CD8+ T cells and thus had a component of immunoregulatory T cells, it was primarily due to anergy, as it was reversible by four daily injections of interleukin (II)-2 starting 3 days after the PLP-ECDI-SP. Earlier treatment with IL-2 did not reverse the tolerance. In view of the known higher sensitivity to anergy induction of Th1 than of Th2 cells, a change in the cytokine balance in the response to MSCH+CFA after anergy induction might be responsible for the resistance to EAE induction. The effect of treatment with cytokines alone on induction of EAE was therefore also determined. Short-term (1-2 weeks) daily pretreatment with IL-2 (4000 U) or TGF-beta 2 (1 micrograms) somewhat decreased the susceptibility to subsequent EAE induction, but IL-4 (5 ng), IL-10 (5 micrograms) or IL-12 (50-200 ng) had no effect under those conditions, even if low doses of PLP were injected simultaneously. Daily injections of IL-4 over an 8-week period prior to immunization, however, significantly lowered the incidence of EAE. Simultaneous injections of IFN-gamma (2000 U/day) completely abolished this effect of IL-4. The effect of these cytokines administered immediately after the immunization with MSCH + CFA + P was also examined. As shown earlier, TGF-beta 2 (100-1000 ng/day) caused a marked protection when it was given intraperitoneally on days 5-9 after injection of MSCH + CFA. IL-4 (5 ng/day), in contrast, was very protective when administered on days 0-4 and less so when given on days 5-9 or even on days 0-12. IL-10 (1 microgram/day) was not protective under these conditions and IL-12 (50 ng/day) significantly increased the severity and mortality of EAE when given on days 0-4 after MSCH + CFA.
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PMID:Tolerogenic forms of auto-antigens and cytokines in the induction of resistance to experimental allergic encephalomyelitis. 775 10

Injection of transforming growth factor beta 1 (TGF-beta 1) for five days during the late phase of the immunization process leading either to collagen type II induced arthritis (CIA) or to experimental allergic encephalomyelitis (EAE) protects against the development of these auto-immune diseases. Tumor necrosis factor alpha (TNF-alpha) injected during this same interval aggrevates CIA. In addition, anti-TGF-beta exacerbates and anti-TNF protects against CIA, acute and relapsing EAE, suggesting an important regulatory role for the endogenous production of the two cytokines on the severity of these diseases. More detailed studies about the mechanism of action of TGF-beta in acute EAE show that there is no detectable effect of TGF-beta on the development of sensitized T cells in vivo, as assayed by the proliferative responses of T cells from lymph nodes and peripheral blood to myelin antigens. Nevertheless, the number of lymphoid cells infiltrating the central nervous tissue is much greater in untreated than in TGF-beta-treated, protected mice. We conclude that it is likely that TGF-beta protects against experimental auto-immune diseases by interfering with the entry of lymphoid cells into the target organs through inhibition of the upregulation of adhesion molecule expression on endothelial cells, and with subsequent inflammatory processes inside the target organs by antagonizing both the production and the effects of TNF.
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PMID:Antagonistic effects of endogenous and exogenous TGF-beta and TNF on auto-immune diseases in mice. 822 72

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


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