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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 (IDDM) is believed to be a consequence of an autoimmune attack on beta cells by T cells. We have previously reported that T cells from the majority of patients with IDDM produced decreased levels of interleukin-2 (IL-2) following activation with phytohemagglutinin. In this study we began to characterize the basis for this defect. First, we tested whether the decreased IL-2 synthesis was due to the secretion of a factor which inhibited the ability of indicator cells to respond to IL-2 or which inhibited IL-2 release by responder cells. Second, we examined steady-state levels of IL-2 mRNA in IDDMs and controls. To make this feasible, given the limited number of peripheral blood lymphocytes (PBL) available from our patients, we depended upon an approach which enabled the generation of large numbers of resting T cells, called G0/G1 cells, from small numbers of PBL. Preliminary experiments demonstrated that G0/G1 cells from IDDMs reproduced the IL-2 defect seen originally with PBL. Our results suggested that the secretion of inhibitory factors could not explain the IL-2 defect. A comparison of steady-state levels of IL-2 mRNA from activated T cells of IDDMs and age-matched controls, however, demonstrated lower levels of IL-2 mRNA in IDDMs compared to controls. Finally, we observed that the IL-2 mRNA in IDDM T cells was less stabile than that in the control cells, suggesting a possible mechanism for the defect.
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PMID:Low interleukin-2 synthesis by type 1 diabetics is regulated at the pretranslational level. 191 57

Eight patients with type I diabetes mellitus (D-I), seven patients with type II diabetes mellitus (D-11) and 8 healthy donors were examined. The disease standing did not exceed 1 year since the moment of the diagnosis establishment. The patients with D-I manifested activation of natural killers (NK) as compared to their activity in the donors and patients with D-II (76.05 +/- 6.5%, 52.33 +/- 9.55% and 55.39 +/- 10.63%, respectively, p less than 0.01) in the presence of the attenuated response of NK to interleukin-2 and alpha-interferon, determined by NK prestimulation. The amount of NK (CD16-positive) in D-I was significantly less than in the donors and patients with D-II. The high activity of NK in D-I correlated with an increase of receptor expression for transferrin on the mononuclear cells of peripheral blood. At the same time 5 out of the 8 patients with D-I and 2 patients with D-II out of the 7 demonstrated the rise of serum alpha-interferon (in the titer 1:40 and over). Activation of NK and the rise of serum interferon may be due to viral etiology of the disease and may play a role in the autoimmune process in patients suffering from D-I.
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PMID:[The functional activity and count of the natural killer cells in patients with recently diagnosed diabetes mellitus types I and II]. 260 54

Peripheral blood lymphocytes from 24 long-standing IDDM patients (mean age 11.4 +/- 3.2 yrs) and 24 matched controls (mean age 7.7 +/- 4.4 yrs) were stimulated with phytohaemagglutinin (PHA) mitogen and PPD, tetanus and diphtheria antigens. Interleukin-2 (IL-2) production was measured from the supernatants of lymphocytes stimulated with PHA in vitro. There was no difference in lymphocyte blast transformation responses between the patients and controls, and IL-2 production was equal in both. It was thus concluded that there is no general immune deficiency in IDDM such as described in the BB rat even though specific immune aberration to certain virus antigens may exist.
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PMID:Lymphocyte responsiveness and interleukin 2 production in type 1 (insulin-dependent) diabetes mellitus. 349 74

BB rats were found to have autoantibodies to gastric parietal cells, thyroid colloid antigens, smooth muscle, and thymocytes. No autoantibodies reactive with pancreatic islet cells (cytoplasmic), thyroid epithelial cells, adrenal cortex, testes, or anterior pituitary sections were identified. BB rats with gastric parietal autoantibodies had modest degrees of lymphocytic gastritis, but none developed iron or vitamin B12 deficiencies. These results suggest that BB rats have an underlying autoimmune diathesis. In addition, reports of peripheral T lymphopenia in such rats were confirmed, and markedly reduced helper T cell and cytotoxic-suppressor T cell subsets were demonstrated. Histological studies also revealed depletions of the T cell areas of spleen and lymph nodes. Furthermore, BB rats exhibited a profound inability to reject skin grafts across major and minor histocompatibility barriers. This was confirmed by mixed lymphocyte culture studies in vitro. BB-rat lymphocytes from either spleen or peripheral blood also showed profoundly reduced responses to T cell mitogens. Although BB-rat lymphocytes could produce normal levels of interleukin-2, they were unable to respond to this T cell growth factor. However, examination of thymuses from BB rats showed largely normal histologies, normal numbers of thymocyte subsets, and good mitogenic responses to con A. Thus, it appears that BB rats may have a thymic or post thymic defect in T lymphocyte maturation. The relevance of the immunologic lesion to the etiology of IDD in BB rats remains to be shown.
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PMID:Autoimmune diatheses and T lymphocyte immunoincompetences in BB rats. 634 99

T-lymphocyte lines specific for islet cell antigens were isolated from the spleen and pancreas of newly diabetic BB rats or from the related strain BBUF. These cell lines were grown in continuous culture with interleukin-2 (IL-2) containing medium for greater than 60 days. Such T-lymphocytes responded by proliferation and IL-2 secretion in the combined presence of islet cell antigens and major histocompatibility (MHC)-matched antigen-presenting cells. By fluorescence-activated cell sorter (FACS) analysis the cells were W3/13+, W3/25+, and OX8-. Thus, both functionally and by cell-surface-marker analysis they appear to be of the T-helper phenotype. The long-term growth and study of anti-islet T-lymphocyte lines will permit a detailed analysis of the role of T-lymphocytes in the pathogenesis of IDDM.
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PMID:Isolation of T-lymphocyte lines with specificity for islet cell antigens from spontaneously diabetic (insulin-dependent) rats. 637 3

Synthesis of interleukin-2 (IL-2) by lymphocytes from 26 insulin-dependent diabetic subjects (IDDM) was compared with that by lymphocytes from 24 nondiabetic control subjects. The control group produced 1.001 +/- 0.071 U/ml (mean +/- SEM). The IDDM group, containing patients diagnosed between 5 days and 10 yr before testing, produced only 0.59 +/- 0.050 U/ml (P less than 0.002). IL-2 synthesis by 6 non-insulin-dependent diabetic subjects (NIDDM) was not decreased (mean +/- SEM, 1.20 +/- 0.04 U/ml). Moreover, decreased levels of IL-2 production was found with lymphocytes of patients in good control, as well as those in poor control. These data suggest that decreased IL-2 synthesis is specific for IDDM, not explainable solely as a consequence of poor metabolic control, and thus, might be involved in the pathogenesis of the disease.
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PMID:Decreased synthesis of interleukin-2 (IL-2) in insulin-dependent diabetes mellitus. 660 55

Interleukin-2 receptors are released in the circulation in response to antigenic ro mitogenic stimulation of T-lymphocytes. Abnormal serum interleukin-2 receptor levels have been found in young children with type 1 diabetes and "prediabetes." We measured interleukin-2 receptor levels in 17 patients with newly diagnosed type 1 diabetes, 21 patients with long-standing type 1 diabetes, 19 patients with long-standing type 2 diabetes, 19 islet-cell antibody positive nondiabetic polyendocrine patients, 12 islet-cell antibody-positive first-degree relatives of patients with type 1 diabetes and compared the results to age- and sex-matched normal controls. We found significantly lower interleukin-2 receptor levels in patients with newly diagnosed and long-standing type 1 diabetes compared to normal controls (87 +/- 11 and 93 +/- 11 vs. 142 +/- 25 and 132 +/- 40 U/ml, P < 0.001 and P < 0.01). There were no significant differences in interleukin-2 receptor levels between prediabetic groups and normal controls or patients with long-standing type 1 or type 2 diabetes. There was no correlation between glycosylated hemoglobin, blood glucose levels, and interleukin-2 receptor in the groups with long-standing type 1 or type 2 diabetes. We conclude that patients with type 1 diabetes have low interleukin-2 receptor serum levels. This phenomenon is acquired close to disease onset and is unlikely to be an early markers of type 1 diabetes.
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PMID:Low interleukin-2 receptor levels in serum of patients with insulin-dependent diabetes. 798 75

Single-locus mutations in mice associated with autoimmune manifestations or influencing them, including lpr, motheaten and xid have been characterized at the molecular level. Mutations have been described in the genes encoding Fc gamma RI, interleukin-2 and natural resistance associated macrophage protein, which are all candidate genes for susceptibility loci associated with autoimmune diabetes in non-obese diabetic mice. Twelve regions of DNA that are associated with disease susceptibility have now been identified in this polygenic model of autoimmunity. In human autoimmune diseases, the region of DNA surrounding the insulin gene that is associated with susceptibility to insulin dependent diabetes mellitus has been narrowed down to 4.1 kilobases.
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PMID:Non-MHC-linked genes in autoimmune diseases. 829 21

Currently, 16 loci that contribute to the development of IDDM in the NOD mouse have been mapped by linkage analysis. To fine map these loci, we used congenic mapping. Using this approach, we localized the Idd3 locus to a 0.35-cM interval on chromosome 3 containing the Il2 gene. Segregation analysis of the known variations within this interval indicated that only one variant, a serine-to-proline substitution at position 6 of the mature interleukin-2 (IL-2) protein, consistently segregates with IDDM in crosses between NOD and a series of nondiabetic mouse strains. These data, taken together with the immunomodulatory role of IL-2, provide circumstantial evidence in support of the hypothesis that Idd3 is an allelic variation of the Il2 gene, or a variant in strong linkage disequilibrium.
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PMID:Mapping of the IDDM locus Idd3 to a 0.35-cM interval containing the interleukin-2 gene. 907 13

Type I (insulin-dependent) diabetes mellitus (IDDM) is an autoimmune disease that results from the destruction of insulin-secreting pancreatic islet beta-cells by autoreactive cells and their mediators. Although its exact cause is not completely understood, it is well established that IDDM is associated with dysregulated humoral and cellular immunity, exemplified by altered production of and response to macrophage- and T cell-derived cytokines and a shift in T helper (Th) cell differentiation in favor of a pathogenic Th1 pathway. Th1 cytokines, including interleukin-2 and interferon-gamma, induced islet beta-cell destruction directly by accelerating activation-induced cell death (apoptosis) and by up-regulating the expression of select adhesion molecules, Th1 cytokines facilitated the pancreatic homing of autoreactive leukocytes, hence enhancing beta-cell destruction. More recently, a role for Th2 cytokines in IDDM pathogenesis was described. Accordingly, local production of Th2 cytokines, in particular interleukin-10, accelerated beta-cell destruction by enhancing autoreactive cell infiltration of the pancreas (insulitis) through modulation of the release of other cytokines and by modulating the microvasculature. Whereas both Th1 and Th2 cytokines are present in peripheral T cells and in the pancreas in IDDM, the mechanism of action and the kinetics of a cell damage induced by Th1 and Th2 cytokines appeared to be distinct. Collectively, this supports the idea that IDDM is not an exclusive Th1-mediated disorder as was suggested, and that both Th1 and Th2 cells and their respective mediators participate and cooperate in inducing and sustaining pancreatic islet beta-cell destruction in IDDM.
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PMID:Clinical review 103: T helper type 1 and 2 cytokines mediate the onset and progression of type I (insulin-dependent) diabetes. 1032 67


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