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Query: UMLS:C0011854 (type 1 diabetes)
 20,749 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Insulin-dependent diabetes mellitus in nonobese diabetic (NOD) mice results from selective destruction of pancreatic islet beta-cells following islet infiltration by mononuclear leukocytes. Cytokines produced by islet-infiltrating mononuclear cells may be involved in beta-cell destruction. Therefore, we analyzed cytokine mRNA expression, by reverse-transcriptase PCR (RT-PCR) assay, in mononuclear leukocytes isolated from pancreatic islets of four groups of mice: diabetes-prone female NOD mice; female NOD mice protected from diabetes by injection of CFA at an early age; male NOD mice with a low diabetes incidence; and female BALB/c mice that do not develop diabetes. We found that mRNA levels of IL-1 beta, IL-2, IL-4, IL-10, and IFN-gamma in mononuclear cells from islets of diabetes-prone female NOD mice increased progressively as these cells infiltrated the islets from age 5 wk to diabetes onset (> 13 wk). However, only IFN-gamma mRNA levels were significantly higher in islet mononuclear cells from 12-wk-old diabetes-prone female NOD mice than from less diabetes-prone NOD mice (CFA-treated females, and males) and normal mice (BALB/c). In contrast, IL-4 mRNA levels were lower in islet mononuclear cells from diabetes-prone female NOD mice than from NOD mice with low diabetes incidence (CFA-treated females and males). Splenic cell mRNA levels of IFN-gamma and IL-4 were not different in the four groups of mice. These results suggest that islet beta-cell destruction and diabetes in female NOD mice are dependent upon intra-islet IFN-gamma production by mononuclear cells, and that CFA-treated female NOD mice and male NOD mice may be protected from diabetes development by down-regulation of IFN-gamma production in the islets.
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PMID:IFN-gamma gene expression in pancreatic islet-infiltrating mononuclear cells correlates with autoimmune diabetes in nonobese diabetic mice. 772 37

Insulin-dependent diabetes mellitus (IDDM), in which only the pancreatic beta cells are destroyed by the autoimmune response, is the paradigm of organ-specific autoimmunity. As a result of a combination of factors, the number of immunohistologic/cellular/molecular studies of pancreas in IDDM is very limited. We report here studies conducted in the pancreata of two IDDM patients: one newly diagnosed (case 1) and one long standing (case 2). In case 1, we demonstrated the presence of morphologically normal viable beta cells without evidence of viral infection. In both cases the expression of the autoantigens defined by islet cell Abs and by glutamic acid decarboxylase was markedly reduced in the islet cells whereas expression of hsp60, another putative autoantigen, was normal. Over-expression of HLA class I was detected in 58% of the islets in pancreatic sections and in cultured beta cells in case 1 and also in 30% of islets in case 2 but it was not restricted to any insular cell type. In case 1, there was "inappropriate" HLA class II expression in islets cells but it was a rare finding and not beta cell specific. The analysis of the correlation between class I overexpression, residual insulin, and insulitis suggests that the first event is the increase of HLA class I expression. Of adhesion molecules, ICAM-1, VLA, VCAM, and LFA-3 were normal and only ICAM-1 was moderately overexpressed in and around the islets of case 1 insulitis, as was detected by immunofluorescence which showed that 18% of the islets of case 1 had CD8+ lymphocytes as the predominant population. Reverse transcription-PCR demonstrated moderate V beta skewing and the profile of cytokines expected in CTLs: IL-2, IL-4, IL-10, and IFN-gamma negative, perforin positive. In addition, IFN-alpha, IFN-beta, and IL-6 transcripts were detected in the case 1 pancreas, consistent with the existence of a silent viral infection. Overall, the results indicated that, differently from spontaneous animal models of diabetes, in the pancreas of IDDM patients there are no elements of the inductive phase of the autoimmune response.
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PMID:Pancreas in recent onset insulin-dependent diabetes mellitus. Changes in HLA, adhesion molecules and autoantigens, restricted T cell receptor V beta usage, and cytokine profile. 791 15

Cytokines produced by islet-infiltrating mononuclear leukocytes may be involved in islet beta-cell destruction and IDDM. To determine which cytokine(s) might be involved in islet beta-cell destruction, we used a reverse transcriptase-polymerase chain reaction assay to compare levels of cytokine mRNA expression in mononuclear leukocytes freshly isolated from islets of four groups of BB rats aged 60-75 days: diabetes-prone (DP) rats, DP rats protected from diabetes by injection of complete Freund's adjuvant (CFA) at age 25 days, acutely diabetic rats, and diabetes-resistant (DR) rats. We found that islet mononuclear leukocyte levels of gamma-interferon (IFN-gamma) mRNA were significantly higher in DP and diabetic rats than in DR rats, whereas CFA-treated DP rats had similar IFN-gamma mRNA levels to DR rats. Also, interleukin (IL)-2 mRNA levels tended to be higher in islet leukocytes from DP and diabetic rats than from DR rats. Tumor necrosis factor-alpha, IL-4, and IL-10 mRNA levels were not significantly different in islet leukocytes from the four groups of rats. These findings suggest that production of T-helper 1 (Th1)-type cytokines, IFN-gamma and IL-2, by islet-infiltrating cells in BB rats is associated with beta-cell destruction and IDDM development.
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PMID:Cytokine gene expression in pancreatic islet-infiltrating leukocytes of BB rats: expression of Th1 cytokines correlates with beta-cell destructive insulitis and IDDM. 863 48

NOD mice constitute a model for studying the prevention of human autoimmune type 1 diabetes. Glutamic acid decarboxylase (GAD) could be a key antigen involved in this disease, and GAD65 peptide 524-543 has been implicated in early T cell response in young NOD mice. We performed two i.p. injections of GAD peptide 524-543 (100 micrograms at each injection), together with Freund's incomplete adjuvant (FIA), into female NOD mice at 30 and 45 days old. Diabetes was accelerated 2 weeks later by a single injection of cyclophosphamide (CY), which acts against suppressive mechanisms. Treatment with GAD 524-543 peptide delayed the onset of diabetes and reduced its incidence (28% versus 60%; P < 0.001) compared with control mice injected with FIA alone, or GAD peptide 534-553, or an irrelevant peptide. In the same group, the severity of lymphocytic inflammation of pancreatic islets was reduced (P < 0.03). Up to 3 months after peptide injections, a strong splenocytic proliferative response occurred in immunized NOD mice against the immunizing peptide alone (but not against a panel of seven other GAD65-derived peptides). After peptide challenge of splenocytes in vitro, protection against CY-accelerated diabetes was associated with higher peptide-specific production of T helper type 2 (Th2)-associated interleukins 4 and 10, whereas Th1-associated interferon-gamma and IL-2 were proportionally less represented. During contransfer, T splenocytes from GAD 524-543-immunized mice were able to reduce the capacity of T cells from diabetic donors to transfer the disease adoptively (P < 0.01), demonstrating the generation of cellular mechanisms that actively suppress the disease. It is concluded that immunization of NOD mice with GAD65 peptide 524-543 can counteract CY-accelerated diabetes, possibly through active cellular suppression linked to a shift of Th1/Th2 balance toward the production of Th2 cytokines such as IL-4 and IL-10. This study provides additional support for the notion that GAD, and more precisely its epitope 524-543, could be one of the key targets for the pathogenesis of type 1 diabetes in NOD mice, as well as for the efficacy of disease-specific peptide therapy in type 1 diabetes.
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PMID:Immunization of non-obese diabetic (NOD) mice with glutamic acid decarboxylase-derived peptide 524-543 reduces cyclophosphamide-accelerated diabetes. 870 42

Insulin-dependent diabetes mellitus (IDDM) is a chronic autoimmune disease and spontaneously develops in NOD mice and humans. The role of T helper 1 (Th1) and T helper 2 (Th2) cytokines in the immunopathogenesis of disease is not understood. IL-10 has presented a particularly paradoxical role. Transgenic (Tg) BALB/c mice expressing IL-10 in the pancreas exhibited periinsulitis but not insulitis and diabetes. However, backcrossing of these Tg mice with NOD mice accelerated the onset of diabetes, indicating a pathogenic role for IL-10 in the pathogenesis of autoimmune diabetes since it is able to replace the genetic susceptibility information on the NOD genome. Conversely, administration of IL-10 to adult NOD delayed the onset of and decreased the incidence of diabetes suggesting a potential therapeutic role for IL-10 in autoimmune diabetes. Overall, the findings indicated a paradoxical role for IL-10 in the immunoregulation of autoimmune diabetes.
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PMID:The paradoxical effects of interleukin 10 in the immunoregulation of autoimmune diabetes. 873 75

Insulin-dependent diabetes mellitus (IDDM) is an autoimmune disease in which cytokines are thought to play an important role in beta-cell destruction and immune regulation. A major target of beta-cell autoimmunity in IDDM is the enzyme glutamate decarboxylase (GAD). We hypothesized that cytokines in the insulitis lesion modulate the synthesis of GAD. This may, in turn, modify the rate of beta-cell destruction. Accordingly we cultured rat islets in the presence and absence of cytokines, and measured synthesis of both isoforms of GAD, GAD65 and GAD67, by [35S]methionine incorporation and immunoprecipitation with a rabbit antiserum that recognizes both GAD65 and GAD67. Incubation of islets with interleukin (IL)-1 beta (1 ng/ml, 24 h), tumour necrosis factor alpha (TNF-alpha; 200 units/ml, 24 h) or interferon gamma (IFN-gamma; 500 units/ml, 72 h) significantly decreased the synthesis of both GAD65 and GAD67, but reduced neither total protein synthesis nor insulin accumulation in the medium or content. Incubation of islets for 24 h in IFN-alpha (1000 units/ml), TNF-beta (50 ng/ml), IL 2 (1000 units/ml), IL-4 (100 ng/ml), IL-6 (10 ng/ml), IL-10 (20 ng/ml), IL-12 (10 ng/ml) or transforming growth factor beta 2 (TGF-beta 2; 5 ng/ml) did not significantly alter GAD65 or GAD67 synthesis. Inhibition of GAD65 and GAD67 protein synthesis by IL-1 beta, TNF-alpha or IFN-gamma was reversed by co-incubation with the nitric oxide synthase inhibitor, NG-monomethyl arginine (NMMA). Expression of both GAD65 and GAD67 mRNA, measured by RNase protection assay, was also decreased by IL-1 beta and completely restored to baseline levels by NMMA. Thus the synthesis of both isoforms of islet GAD is selectively decreased in the presence of IL-1 beta, TNF-alpha or IFN-gamma by a NO-mediated mechanism, probably at the level of cytokine gene transcription. As GAD autoimmunity has been previously shown to have a pathogenic role in an animal model of IDDM, its inhibition by cytokines might limit the immune response, thereby regulating the rate of beta-cell destruction in IDDM.
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PMID:Cytokine regulation of glutamate decarboxylase biosynthesis in isolated rat islets of Langerhans. 876 Mar 54

We evaluated the role of the costimulatory molecule B7-1 in overcoming peripheral ignorance in transgenic mice, which expressed the glycoprotein (GP) or nucleoprotein (NP) of lymphocytic choriomeningitis virus (LCMV) as the self-antigen in pancreatic beta cells. The viral transgenes or B7-1 alone did not induce autoimmune diabetes (IDDM). However, in bigenic mice expressing B7-1 and LCMV-GP, anti-self (viral) cytotoxic T lymphocytes (CTL) were activated without viral infection and spontaneous IDDM occurred. In contrast, bigenic RIP-B7-1 x RIP-NP mice with thymic expression of the self (viral-NP) antigen deleted the majority of their autoreactive CTL and did not develop spontaneous IDDM. However, these mice developed fast-onset IDDM 14 days after LCMV infection, whereas single-transgenic RIP-NP littermates developed IDDM only within 4-5 months. Rapid IDDM was associated with increased numbers of anti-self CTL and a predominance of IFN gamma produced by islet-infiltrating lymphocytes, whereas single transgenic RIP-NP littermates with slow-onset IDDM displayed less anti-self CTL and more IL-4- and IL-10-producing T lymphocytes in pancreatic infiltrates.
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PMID:Coexpression of B7-1 and viral ("self") transgenes in pancreatic beta cells can break peripheral ignorance and lead to spontaneous autoimmune diabetes. 877 18

Insulin-dependent diabetes mellitus (IDDM) in the non-obese diabetic (NOD) mouse results from effector T cell-mediated autoimmune processes directed against pancreatic beta cells. These effector T cell-mediated beta cell-specific autoimmune processes can be blocked by transfusion with supressor T cells. The CD4+ autoreactive T cell clone, NY4.2, isolated from lymphocytes infiltrating the pancreatic islets of NOD mice was transfused into young NOD mice and none of the animals became diabetic. Similarly, when NY4.2 cells were transfused into acutely diabetic NOD mice prior to syngeneic islet transplantation, the grafted islets were not destroyed and the animals maintained normoglycaemia. This investigation was initiated to determine how our cloned CD4+ autoreactive suppressor T cells are able to inhibit effector T cell-mediated beta cell destruction in NOD mice. We found that NY4.2 cells, which responded to self MHC class II determinants, had a significant immunosuppressive effect on proliferative responses of splenic effector T cells from NOD mice. This suppressive activity of the NY4.2 cells was a result of soluble factors secreted by them. The clone was found to produce substantial amounts of transforming growth factor beta (TGF-beta), IL-10, and IFN-gamma, but not IL-2 or IL-4, indicating that this T cell clone is not a member of either the classic Th1 or Th2 cell type. The suppressive activity of NY4.2 cells was abrogated by treatment with anti-TGF-beta antibodies, but not by treatment with anti-IL-10 or anti-IFN-gamma antibodies. On the basis of these observations, we suggest that a new type of CD4+ suppressor T cell, NY4.2, by secreting TGF-beta, can prevent effector T cell-mediated beta cell destruction.
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PMID:A new type of CD4+ suppressor T cell completely prevents spontaneous autoimmune diabetes and recurrent diabetes in syngeneic islet-transplanted NOD mice. 881 68

Disturbed immune regulation has been postulated to be crucial in the pathogenesis of IDDM and other autoimmune or allergic diseases. We therefore tested the hypothesis of a general bias in the peripheral immune system in patients with recent-onset IDDM or Graves' disease in comparison to healthy control subjects by studying whole blood cultures stimulated with phytohemagglutinin. Cells from IDDM patients (n = 53) produced significantly higher amounts of Th1 cytokines gamma-interferon (IFN-gamma) (P = 0.028) and tumor necrosis factor alpha (TNF-alpha) (P = 0.007) than normal control subjects (n = 56), while Th2 cytokine levels (interleukin [IL]-4, IL-10) were similar. Low levels of islet cell antibodies (ICAs) in IDDM patients were associated with high levels of Th1 and Th2 cytokines. Antibodies to GAD, ICA512, or insulin did not correlate with individual cytokine profiles. Also, HLA-DQ types did not significantly correlate with either Th1 or Th2 cytokine production. Conversely, whole blood cultures from patients with Graves' disease (n = 18) produced significantly less TNF-alpha and IL-4 than normal subjects (P = 0.001-0.006). However, when the balance between Th1 and Th2 cytokine production was analyzed in individuals, the ratio between IFN-gamma or TNF-alpha and IL-4 or IL-10 was clearly biased toward Th1 reactivity in patients with IDDM (P = 0.0001), while a dominance of Th2 cytokine production was seen in Graves' disease (P = 0.0001). The ratio of counterregulatory cytokines appeared to be the most reliable marker of the individual disease process. This study provides first evidence of a systemic bias in the immune regulation of humans, which might be either toward cell-mediated immunity (Th1) in IDDM or humoral immunity (Th2) in Graves' disease.
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PMID:Systemic bias of cytokine production toward cell-mediated immune regulation in IDDM and toward humoral immunity in Graves' disease. 900 Jul

Previous studies have shown that type I diabetes (IDDM) increases the risk of developing periodontitis by 2-3-fold. IDDM patients exhibit destruction of the pancreatic beta cells, most probably caused by an autoimmune reaction. Evidence is accumulating to support the role of the autoimmune response in periodontal pathogenesis. A cytokine, interleukin (IL)-10, has been reported to selectively promote the expansion of a B lymphocyte lineage (CD5/LY1/B1) which has the propensity for secreting high levels of autoantibody. Therefore, the purpose of this project was to evaluate IL-10 production, percentage of CD5 B cells and the frequency of anti-collagen secreting cells in peripheral blood mononuclear cells of age, gender and race matched IDDM patients and controls. IL-10 production was evaluated by an ELISA using the supernatant of adherent peripheral blood cells cultured for 24 h in the presence of Porphyromonas gingivalis lipopolysaccharide (LPS). In 8 of 31 patients, IL-10 levels were significantly increased in IDDM compared to controls and a higher percentage of CD5 B cells was also observed by flow cytometry. In addition, these patients exhibited a higher frequency of anti-collagen secreting cells as elucidated by an ELISPOT. Moreover, treatment with a neutralizing anti-IL-10 antibody diminished the anti-collagen antibody response by 70%. These findings support the concept that a subset of IDDM patients possess an extremely robust IL-10 response following exposure to Gram-negative LPS, which could predispose them to the development of periodontitis through a heightened autoimmune mechanism.
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PMID:Interleukin-10 promotes anti-collagen antibody production in type I diabetic peripheral B lymphocytes. 908 33


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