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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Oral administration of autoantigens suppresses development of autoimmunity in several animal models, and is being tested in clinical trials in patients with autoimmune diseases such as multiple sclerosis and rheumatoid arthritis. Non-obese diabetic (NOD) mice spontaneously develop insulin-dependent diabetes mellitus at 15 to 20 weeks of age, after mononuclear cell (MNC) infiltration of the pancreatic islets of Langerhans and destruction of insulin-producing beta cells. We have previously shown that oral administration of insulin suppresses insulitis and development of diabetes in the NOD mouse. Oral insulin has no metabolic effect on blood glucose. Oral insulin mediates its effect through a T cell-dependent mechanism as shown by adoptive transfer and T cell depletion experiments, but the mechanisms responsible have not been fully explored. We now report a serial analysis of the cells and cytokines associated with development of diabetes in NOD mice, and contrast this with the findings in animals fed equine insulin or a control protein (ovalbumin). Animals were fed 1 mg twice a week for 5 weeks, beginning at 5 weeks of age. Marked insulitis in naive or ovalbumin-fed NOD mice occurred at 10 weeks, at which time a dense peri-islet and intra-islet MNC infiltration was observed. Immunohistological studies using monoclonal antibodies showed that infiltrating MNC consisted mainly of CD4+ T cells ( > 75% of leukocytes) plus smaller numbers of macrophages and CD8+ T cells. These cells displayed evidence of immune activation with expression of receptors for interleukin-2 (IL-2R) plus Th1 cytokines; dense labeling for IFN-gamma and tumor necrosis factor-alpha, plus lesser amounts of IL-2, was observed. MNC lacked labeling for IL-4, IL-10, prostaglandin-E, or transforming growth factor-beta. By contrast, at 10 weeks, pancreatic tissues from NOD mice fed insulin showed considerably less insulitis, and the residual MNC, although still largely CD4+ T cells plus macrophages, showed dense labeling for IL-4, IL-10, prostaglandin-E, and transforming growth factor-beta and an absence of IL-2, IFN-gamma or tumor necrosis factor-alpha Taken together with our previous findings, these data indicate that oral administration of insulin affects the development of diabetes in NOD mice through the generation of cells that elaborate immunoregulatory cytokines within the target organ and shift the balance from a Th1 to a Th2 pattern of cytokine expression.
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PMID:Suppression of insulitis in non-obese diabetic (NOD) mice by oral insulin administration is associated with selective expression of interleukin-4 and -10, transforming growth factor-beta, and prostaglandin-E. 748 82

Murine macrophages express high levels of nitric oxide synthase and produce large amounts of nitric oxide (NO) when stimulated with certain cytokines in the presence of a trace amount of lipopolysaccharide (LPS). The stimulatory cytokines include interleukin-1 (IL-1), interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha) and migration inhibitory factor. Activated macrophages are highly effective killers of intra- and extra-cellular pathogens. However, as excessive NO can lead to immunopathology (diabetes, graft-v.-host disease, EAE, liver cirrhosis, rheumatoid arthritis), NO production is necessarily under tight regulation. A number of cytokines, including IL-4, IL-10 and transforming growth factor-beta, can down regulate the induction of NO synthase in macrophages. In addition, macrophages exposed to LPS alone and then stimulated with a mix of IFN-gamma and LPS express significantly lower levels of NO synthase than cells stimulated without pre-exposure to LPS. Furthermore, NO can reduce the activity of NO synthase by feedback inhibition, and also inhibit the production of IFN-gamma by Th1 cells (thus turning off its own synthesis from upstream). The regulatory pathways involve tyrosine kinase and protein kinase C.
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PMID:The role of nitric oxide in parasitic diseases. 751 Jan

Syngeneic pancreatic islet grafts in nonobese diabetic (NOD) mice elicit a cell-mediated autoimmune response that destroys the insulin-producing beta cells in the islet graft. IL-4 and IL-10 are cytokines that inhibit cell-mediated immunity. In this study, we evaluated the effects of IL-4 and IL-10 on the survival of syngeneic pancreatic islets transplanted into diabetic NOD mice. Islet grafts survived beyond 18 days and normoglycemia was maintained in 67% (10 of 15) of mice treated with IL-4 plus IL-10, but in none (0 of 20) of vehicle-injected (control) mice. Also, 40% (6 of 15) of the mice treated with IL-4 plus IL-10 were normoglycemic at 30 days after transplantation, compared with 14% (1 of 7) of the mice treated with IL-4 alone, 8% (1 of 13) of the mice treated with IL-10 alone, and none (0 of 20) of the control mice. Histological examination of grafts at 10 days after transplantation revealed peri-islet accumulations of mononuclear leukocytes and intact islet beta cells in grafts from IL-4 plus IL-10-treated mice, whereas islets were infiltrated by leukocytes and the beta cell mass was greatly reduced in grafts from control mice. Polymerase chain reaction (PCR) analysis of cytokine mRNA expression in the grafts revealed higher levels of IL-2, IFN gamma, and IL-10 mRNA in grafts of diabetic compared with normoglycemic control mice, whereas IFN gamma and TNF alpha mRNA levels were significantly decreased in grafts of IL-4 plus IL-10-treated mice compared with either normoglycemic or diabetic control mice. These results suggest that T helper (Th)1 cells and their cytokine products (IL-2, IFN gamma, and TNF alpha) may promote islet beta cell destructive insulitis and autoimmune diabetes recurrence in syngeneic islet-transplanted NOD mice, and that administration of IL-4 plus IL-10 may inhibit diabetes recurrence by suppressing Th1 cytokine production in the islet grafts.
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PMID:Combined therapy with interleukin-4 and interleukin-10 inhibits autoimmune diabetes recurrence in syngeneic islet-transplanted nonobese diabetic mice. Analysis of cytokine mRNA expression in the graft. 765 67

To study the paracrine effect of IL-10 on autoimmune insulitis and diabetes, we produced IL-10 transgenic non-obese diabetic (NOD) mice (NOD-IL-10) in which murine IL-10 was expressed in pancreatic islet A cells under the control of a rat glucagon promoter without directly manipulating pancreatic islet B cells. Among 11 founder mice, four of four males and three of seven females developed diabetes by 10 weeks of age. Histological analysis of six NOD-IL-10 revealed severe insulitis and prominent ductal proliferation. NOD-IL-10 also showed spotty lymphocytic infiltration in the lung and liver in four of six founder mice. The onset of diabetes in NOD-IL-10 was remarkably earlier than that of 14 weeks of age at the earliest in female non-transgenic NOD mice. When the NOD-IL-10 mouse was backcrossed to C57BL/6 mice, none of the resulting F1, B-N2 or B-N3 generation toward C57BL/6 mice showed diabetes even at 39 weeks of age, in spite of the presence of peri-insulitis and prominent ductal proliferation, while two of four mice of the N-N2 generation toward NOD mice showed early-onset diabetes. Thus, transgenic paracrine expression of IL-10 in situ in the NOD genetic background enhances autoimmune insulitis and diabetes in their onset and severity, ignoring gender difference. Because expression of IL-10 was detected by polymerase chain reaction in pancreatic islets of non-transgenic NOD mice after 5 weeks of age, IL-10 secreted in situ is regarded to enhance cell-mediated autoimmune diabetes, in spite of established in vitro anti-Th1 activity of IL-10.
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PMID:Transgenic expression of IL-10 in pancreatic islet A cells accelerates autoimmune insulitis and diabetes in non-obese diabetic mice. 769 10

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

Type I, insulin-dependent diabetes (IDD) in both man and animals results from a specific autoimmune destruction of the pancreatic beta cells involving both humoral and cellular immune mechanisms. The pathognomonic histologic lesion, termed insulitis, is an inflammatory and immune cell infiltrate of the pancreatic islet cells. While recent histological and flow cytometric analyses have identified the cell composition of the infiltrate, the presence of a cell population may not reflect the functional reactivities important for beta cell destruction. In the present study, we have investigated the possible functional reactivities of islet-infiltrating mononuclear cell populations by measuring increased cytokine mRNA usage. Results indicate that 1) cytokine mRNA profiles exhibited by islet-infiltrating cells of female and male NOD mice were quite similar with the exception of IL-6 expression and the marked differences in the levels of IL-2 receptor and IL-1 alpha mRNA, 2) CD4+ T lymphocytes expressed IL-4, presumably IL-5, and occasionally IL-10 mRNA but no detectable IL-2 mRNA, 3) CD8+ T lymphocytes exhibited TNF-beta, perforin and high levels of IFN-gamma, and 4) IL-7 was expressed in the islet at very high levels. These findings, together with our earlier flow cytometric analyses of the islet-infiltrating cells, have permitted construction of a detailed model for the natural history of autoimmune diabetes. Interestingly, this model, based on a TH2- and not a TH1-mediated scheme, questions the more popular concepts currently thought to form the bases of the autoimmune reactions underlying IDD.
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PMID:Insulin-dependent diabetes in the NOD mouse model. II. Beta cell destruction in autoimmune diabetes is a TH2 and not a TH1 mediated event. 810 89

IL-10 inhibits macrophage-dependent antigen presentation, cytokine production, and generation of allospecific cells in vitro. These findings have lead to the widespread expectation that IL-10 may be a useful immunosuppressive agent to inhibit allograft rejection or autoimmunity in vivo. We used two experimental paradigms to study effects of murine IL-10 on in vivo immune responses. First, fetal pancreata or adult pancreatic islets from transgenic mice expressing IL-10 in pancreatic beta cells (Ins-IL-10 mice) were grafted across the MHC barrier to examine if IL-10 could inhibit allograft rejection. Second, Ins-IL-10 mice were crossed with transgenic mice expressing lymphocytic choriomeningitis virus (LCMV) antigens in pancreatic beta cells. These mice were infected with LCMV to elicit autoimmune diabetes, allowing us to ask if IL-10 protects islets from autoimmune destruction. We observed that allografts from IL-10-transgenic donors were rejected with comparable kinetics to the rejection of control nontransgenic allografts, indicating that IL-10 does not inhibit allograft rejection. After LCMV infection, IL-10 and LCMV antigen double transgenic mice developed diabetes earlier than LCMV antigen single transgenic littermates, suggesting that IL-10 does not inhibit islet antigen presentation or recognition. Our results contrast to in vitro observations and suggest that IL-10 cannot overcome immune-mediated tissue destruction within the pancreas.
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PMID:Pancreatic islet production of murine interleukin-10 does not inhibit immune-mediated tissue destruction. 813 75

The autoimmune response that leads to destruction of pancreatic islet beta-cells and insulin-dependent diabetes mellitus (IDDM) has a genetic basis; however, environmental factors can exert profound modulating effects on the genetic predisposition to this autoimmune response. Recent studies in animal models for human IDDM, the genetically diabetes-prone NOD mouse and BB rat, have revealed that microbial agents--including certain viruses and extracts of bacteria, fungi, and mycobacteria--often have a protective action against diabetes development. Many of these microbial preparations are immune adjuvants, which are agents that stimulate the immune system. The protective effects of these agents against diabetes appear to involve perturbations in the production of cytokines, which are polypeptides produced by and acting on cells of the immune system. Thus, recent studies in NOD mice suggest that the islet beta-cell-directed autoimmune response may be mediated by a T-helper 1 (Th1) subset of T-cells producing the cytokines interleukin-2 (IL-2) and interferon-gamma. These studies also suggest that the diabetes-protective effects of administering microbial agents, adjuvants, and a beta-cell autoantigen (GAD65 [glutamic acid decarboxylase]) may result from activation of a Th2 subset of T-cells that produce the cytokines IL-4 and IL-10 and consequently downregulate the Th1-cell-mediated autoimmune response. The clinical implication of these findings is that the autoimmune response leading to islet beta-cell destruction and IDDM may be amenable to prevention or suppression by therapeutic interventions aimed at stimulating the host's own immunoregulatory mechanisms.
Diabetes 1994 May
PMID:Immunoregulatory and cytokine imbalances in the pathogenesis of IDDM. Therapeutic intervention by immunostimulation? 778 55

The role of IL-10 in the pathogenesis of autoimmune diabetes mellitus was assessed in the nonobese diabetic (NOD) mouse. In these studies the effect of IL-10 was determined on three parameters of diabetes: The development of hyperglycemia, the development of insulitis, and the production of insulin by beta cells. Initial experiments investigated the effect of anticytokine antibodies on the development of disease. These results indicated that monoclonal anti-IFN-gamma antibody greatly reduced the incidence of hyperglycemia in female NOD mice, while anti-IL-4, IL-5, and IL-10 were ineffective. In subsequent studies, daily subcutaneous administration of IL-10, a known potent inhibitor of IFN-gamma production by TH1 T cells, to 9 and 10-week-old NODs was shown to delay the onset of disease and significantly reduce the incidence of diabetes. Histopathology performed on pancreatic tissue demonstrated that treatment with IL-10 reduced the severity of insulitis, prevented cellular infiltration of islet cells, and promoted normal insulin production by beta cells. Taken together these results indicate IL-10 suppresses the induction and progression of autoimmune pathogenesis associated with diabetes mellitus and suggest a potential therapeutic role for this cytokine in this autoimmune disease.
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PMID:Recombinant human IL-10 prevents the onset of diabetes in the nonobese diabetic mouse. 818 Nov 85


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