Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0011854 (type 1 diabetes)
 20,749 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immunophenotyping of the early lesion in the pancreatic islets of Langerhans demonstrates a predominance of CD4+ lymphocytes, which may be preceded by an increase in islet macrophages. This observation implies that both types of cells may be involved in autoimmune-mediated beta-cell destruction leading to IDDM. In an attempt to attribute a role to beta-cell antigen-specific CD4-expressing T-cell clones recently isolated from a newly diagnosed IDDM patient, we investigated whether such CD4 T-cells may be pathogenic in an in vitro cytotoxicity assay with HLA-DR-matched antigen-presenting macrophages as target. We report herein that, indeed, beta-cell antigen-specific CD4+ T-cells are capable of lysing macrophages in an antigen-specific fashion. This cytotoxicity is HLA-DR restricted, T-cell receptor complex mediated, and CD4 dependent. These observations imply that both helper T-cells and macrophages may be involved in the disease process via interaction between T-cells and macrophages pulsed with beta-cell antigen.
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PMID:Beta-cell antigen-specific lysis of macrophages by CD4 T-cell clones from newly diagnosed IDDM patient. A putative mechanism of T-cell-mediated autoimmune islet cell destruction. 139 14

Alterations of lymphocyte subsets have been recently reported in pre-type 1 diabetes but the relation with other immunological markers, in particular islet cell antibodies (ICA), is still unknown. In the present study, we have investigated prospectively changes of lymphocyte subsets in 86 first-degree relatives of patients affected by type 1 diabetes and correlated such modifications with ICA titres. Among individuals with persistent ICA, 8 had ICA titres of more than 20 JDF units, 14 had ICA titres between 5 and 20 JDF units and 64 had ICA titres between 0 and 5 JDF units. First-degree relatives with ICA titres of more than 20 JDF units had significantly decreased proportions of CD3 cells. This reduction was predominantly in the CD4 subset, giving rise to a decreased CD4/CD8 lymphocyte ratio. Those with ICA titres between 5 and 20 JDF units showed abnormalities in both CD3 and CD4 lymphocytes, but not in CD4/CD8 lymphocyte ratio. Further characterization of the CD4 cell subset was performed using three other monoclonal antibodies, CD45RO (UCHL1), CD45RA and CD29, phenotyping memory T-cells, the inducer cells of suppressor function and helper-inducer cells, respectively. The proportions of total CD45RO and CD45RA were not significantly different among first-degree relative with distinct ICA titres in a cross-sectional study, whereas a trend towards a reduced proportion of CD4/CD45RA cells was observed. The longitudinal study demonstrated that individuals potentially susceptible to the development of type 1 diabetes and who possess high titres of ICA have impairment of CD4/CD8 lymphocyte ratio, mainly due to a reduction in the CD4 subset.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Early T-cell defects in pre-type 1 diabetes. 153 43

We investigated the therapeutic effect of anti-lymphocyte serum (ALS) on clinically overt diabetes by using a nonobese diabetic (NOD) mouse model of type I diabetes mellitus. ALS given within 14 days of disease onset gradually reversed hyperglycemia with a 76% cumulative incidence of remission. Combined use of anti-CD4 and anti-CD8 monoclonal antibodies, but not anti-CD4 or anti-CD8 antibody alone, was also effective with overall 64% remission. Diabetic NOD mice that failed to respond to ALS treatment accepted subsequent islet isografts for a prolonged period (mostly greater than 100 days), whereas islet isografts in diabetic NOD mice previously treated with normal rabbit serum were all destroyed as acutely as isografts in untreated diabetic NOD mice. These results suggest that persistence of diabetes was due to irreversible beta-cell destruction and that ALS has indeed abrogated autoimmunity. In addition, ALS treatment at the time of islet isografting achieved significant prolongation of graft survival with 8 of 13 mice maintaining euglycemia for greater than 100 days. Although ALS prolonged islet allograft survival in diabetic NOD mice, the degree of prolongation was much less for allografts than for isografts, suggesting that ALS is capable of suppressing autoimmunity more effectively than allograft responses.
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PMID:Long-term abrogation of autoimmune diabetes in nonobese diabetic mice by immunotherapy with anti-lymphocyte serum. 156 35

We studied 18 newly diagnosed diabetic patients (8 males and 10 females, aged 18-26 years, within 10-120 days from the onset of symptoms) who were submitted for 15 days to intensive insulin therapy performed via subcutaneous insulin infusion (CSII). We investigated some metabolic and immunological parameters in order to identify a possible marker to predict the selection of patients potentially more responsive to CSII treatment for the remission of type 1 diabetes. In accordance with the International Diabetes Immunology Group we considered clinical remission as being the withdrawal of insulin therapy for at least 3 months. In order to assess beta-cell function a fasting and post-prandial serum C-peptide, blood glucose and HbA1c were performed on all patients before, and 3 days after, the discontinuation of CSII. Islet cell antibodies were determined in all sera by indirect immunofluorescence. Analysis of T-lymphocyte subpopulations was carried out before starting the therapy. The following monoclonal antibodies were used: CD4, CD8, CD57, CD25, HLA-DR. The levels of C3 and C4 and serum IgG, IgA and IgM were also evaluated. After CSII, 11 of 18 patients showed remission. At the beginning of the study we observed no major difference in metabolic parameters between the two groups. Interestingly, the patients who exhibited remission presented a statistically higher percentage of positive cells for CD57, HLA-DR and CD25 surface antigens, significantly lower C4 levels and CD4/CD8 ratio and significantly higher IgG levels compared with patients who did not show any remission.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:In search of predictive markers of remission from insulin dependence in type 1 diabetes: a preliminary report. 160 Aug 53

Type 1 diabetes seems to be an autoimmune disease in which T cells have a substantial role. A possible target antigen was suggested by the proliferation of CD4 T cells from a newly diagnosed patient in response to a 38 kD polypeptide of the insulin-secretory-granule membrane. To see whether this reactivity is widespread at disease onset, we have generated T-cell lines in vitro from peripheral blood mononuclear cells of nineteen children of caucasoid origin with newly diagnosed type 1 diabetes and sixteen healthy controls matched for age and HLA antigens. The procedure involved two cycles of incubation with a rat beta-cell tumour subcellular fraction enriched in secretory granules and plasma membrane components, followed by a proliferation assay. Fourteen (74% [95% confidence interval 49-91%]) of the patients' cell lines showed a positive proliferative response on subsequent exposure to the islet-cell antigen preparation compared with only two (13% [2-38%]) of the controls (p = 3 x 10(-4); difference 61% [44-87%]). Two subjects who had high titres of islet-cell autoantibodies (ICA) without clinical diabetes produced responsive T-cell lines. Reactivity towards the 38 kD fraction of insulin-secretory-granule membranes was found only in patients (eight of ten responders tested; 95% CI 44-98%) and one ICA-positive non-diabetic subject. Detection of an ongoing autoimmune T-cell response might be useful diagnostically and could lead to prevention of diabetes through specific immunotherapy.
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PMID:T-cell reactivity to 38 kD insulin-secretory-granule protein in patients with recent-onset type 1 diabetes. 167 18

Pancreatic beta cell destruction in the non-obese diabetic (NOD) mouse is mediated by T lymphocytes and macrophages and accelerated by cyclophosphamide. We purified pancreatic T lymphocytes from the NOD mouse for comparative phenotypic and functional analysis with T lymphocytes from spleen, peripheral blood and regional lymph nodes. Pancreatic T lymphocytes from NOD-Wehi mice, which have an incidence of spontaneous diabetes of less than 5%, had a CD4:CD8 ratio of 1.25 +/- 0.23 compared with 2.44 +/- 0.31 for peripheral blood lymphocytes. After cyclophosphamide, the CD4:CD8 ratio of pancreatic lymphocytes increased to 2.30 +/- 0.24 at day 7. T lymphocytes bearing IL-2 receptors increased two- to three-fold in number and their secretion of GM-CSF/IL-3 and IFN-gamma increased to a maximum on day 7. Pancreatic insulin content and mRNA levels declined sharply between days 10 and 12, at which time the majority of pancreatic T lymphocytes in hyperglycaemic mice were CD8+ (CD4:CD8 ratio 0.63 +/- 0.04 compared to 4.14 +/- 1.05 in peripheral blood). The pancreatic T lymphocyte CD4:CD8 ratio in prediabetic NOD-Lt mice, which have an incidence of spontaneous diabetes of about 60% at 150 days, was similar to that in untreated NOD-Wehi mice, but 25% of their pancreatic CD8 T lymphocytes were IL-2-receptor positive. Thus, significant changes in the phenotype of NOD pancreatic T lymphocytes following cyclophosphamide were not reflected in peripheral blood or spleen T lymphocytes. The earliest change after cyclophosphamide was an increase in activated, predominantly CD4+ T lymphocytes; with the development of beta cell destruction and hyperglycaemia, pancreatic T lymphocytes were, as in human IDDM, predominantly CD8+.
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PMID:Characterization of pancreatic T lymphocytes associated with beta cell destruction in the non-obese diabetic (NOD) mouse. 167 32

Fifteen women with positive islet cell antibodies were identified in a group of 115 consecutive patients found to have impaired glucose tolerance in pregnancy. These subjects were postulated to be at increased risk of later developing type 1 diabetes mellitus. They were examined post--partum for HLA types known to be associated with this disease and for any increase in Interleukin 2 receptor expression or alteration of T cell subsets of possible relevance to its pathogenesis. Fifteen women negative for islet antibodies and with normal glucose tolerance during previous pregnancy and 15 women with a normal fasting plasma glucose who had never been pregnant were studied as controls. Using flow cytometric techniques a significant increase in both the number and proportion of activated (Interleukin 2 receptor, CD25) lymphocytes in the peripheral blood of women who had islet cell antibodies and previous impaired glucose tolerance in pregnancy was found (0.14 +/- SE 0.03 x 10(9)/l; 7.1 +/- 1.1%) when compared with normal parous controls (0.09 +/- 0.01 x 10(9)/l; 4.2 +/- 0.6%), p less than 0.01 x 10(9)/l; showed significant increases when compared with nulliparous controls (0.04 +/- 0.01 x 10(9)/l; 2.1 +/- 0.2%), p less than 0.01. No differences were detected between the three groups with respect to total T-lymphocytes (CD3), helper T-lymphocytes (CD4), suppressor cytotoxic T-lymphocytes (CD8), or the inducer of suppressor (Leu 3+/Leu 8+) subset of T-lymphocytes. Three women persistently islet cell antibody positive, two of whom were HLA DR4, showed impaired glucose tolerance at the time of lymphocyte subset analysis, while two further patients, one DR3 and the other DR4, had developed type 1 (insulin-dependent) diabetes. No correlation between increased Interleukin 2 receptor expression and glucose intolerance was demonstrated. We conclude that islet cell antibody positive women with impaired glucose tolerance during pregnancy are at increased risk of later developing type 1 diabetes but that heightened immune activation present in these women is in part a post-pregnancy phenomenon.
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PMID:Increased interleukin 2 receptor expression in post-gestational women: relationship to impaired glucose tolerance and islet cell antibodies in pregnancy. 210 86

The increased binding in vitro of CD3 CD4 T-lymphocytes from type 1 (insulin-dependent) diabetic patients to beta-cell membrane antigens compared to lymphocytes from control subjects was previously shown to be a marker of cell-mediated immunity, called diabetic rosettes. In the present study diabetic rosettes were detected in some subjects at risk for type 1 diabetes (first degree relatives of type 1 diabetic patients or nondiabetic subjects with previous transient hyperglycaemia). The mean number of lymphocytes adherent to beta-cells (beta-CL) was significantly higher in subjects at risk for type 1 diabetes than in age- and sex-matched control blood bank donors (P less than 10(-6]. This number of beta-CL was higher in type 1 diabetic patients than in subjects at risk (P less than 10(-6], and one-way analysis of variance by rank (Kruskal-Wallis) revealed that the three populations (controls, diabetics, and risk subjects) were different in terms of beta-CL values (P less than 0.001). The percentage of subjects at risk that had a positive test (arbitrarily defined as a beta-CL value higher than the 95th percentile of 228 controls) was 20%. No difference was observed between the two subgroups of subjects at risk in terms of either mean +/- SEM of beta-CL or percentages of individuals with a positive test. These diabetic rosettes were slightly associated with acute insulin response to iv glucose lower than the 5th percentile of controls (immunoreactive insulin at 1 +/- 3 min, 250 pmol/L; by chi 2, P = 0.04) and with HLA DR 3/4 heterozygosity (by chi 2, P = 0.04). They were not associated with islet cell antibodies (regardless of the threshold for positivity, expressed in Juvenile Diabetes Foundation units), insulin autoantibodies, activated (HLA DR+) T-lymphocytes, or sex. A statistical association was detected between HLA DR 3/4 heterozygosity and a low acute insulin response to iv glucose (by chi 2, P less than 0.003). The preliminary (2-yr) longitudinal follow-up revealed that out of five islet cell antibody-positive subjects who progressed to type 1 diabetes, three displayed beta-CL values higher than the 90th percentile of controls. Diabetic rosettes could, thus, be detected in some individuals at risk for type 1 diabetes as a marker of cell-mediated immunity.
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PMID:Beta-cell cytoadherent lymphocytes in some subjects at risk for type 1 (insulin-dependent) diabetes: progression to diabetes within 2 years. 214 83

Over 80% of nonobese diabetic (NOD) mice develop lymphocytic infiltrates of their pancreatic islets (insulitis) by 6 wk of age and 50% of the females are diabetic by 6 mo of age. The incidence of insulitis in NOD mice injected once as neonates with 250 micrograms of the CD3 antibody, 145.2C11, was 8% at 10 wk of age, increasing to 25% at 32 wk of age. Fewer than 10% of these animals developed diabetes by 8 mo of age. Neonatal administration of 145.2C11 reduced the proliferative responses of spleen cells to mitogen stimulation 2 and 4 wk postinjection and expression of TCR was reduced 1 to 5 wk postinjection. The percentage of CD4 and CD8 cells in the spleen was transiently reduced after injection and the frequency of Pgp-1+-high cells (putative memory cells) was increased 2 to 4 wk postinjection, suggesting that in vivo administration of the antibody caused some T cells to divide as well as transiently reducing T cell numbers. IL-2R expression was not detected on spleen cells in the 4 wk after antibody injection. The phenotypic and functional changes after neonatal CD3 antibody injection resolved by 8 wk of age. The control and injected mice grew normally and made equivalent IgG antibody responses to injected human IgG. Neonatally injected 145.2C11 antibody was cleared from the circulation with a terminal half-life approximating to 21 days but greater than 90% of antigen binding activity was lost 6 days after injection. Protection from diabetes did not follow neonatal elimination of T cells with CD4 and CD8 antibodies, nor the injection of a TCR subset antibody, F23.1. Our data suggest that the neonatal T cell repertoire is open to modulation by a single injection of a CD3 antibody and they offer a new experimental approach to immunotherapy in an animal model of type 1 diabetes.
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PMID:Neonatal injection of CD3 antibody into nonobese diabetic mice reduces the incidence of insulitis and diabetes. 252 66

Corticosteroids and anti-thymocyte globulin (ATG) have been extensively used in the treatment of autoimmune diseases, aplastic anemia and organ graft rejection; nonetheless, the precise mechanisms of action of these agents are unknown. Studies of their long term immunoregulatory effects, particularly in humans, have been limited. We examined the long term effects of therapy with ATG given for 2-4 weeks and prednisone for 2 months in 4 patients with newly diagnosed insulin dependent diabetes (IDD). Three matched newly-diagnosed untreated IDD patients and 17 healthy volunteers served as controls. No differences in total lymphocyte count, percentage of B cells, percentage of total T cells (CD3), helper-inducer T cells (CD4) or cytotoxic-suppressor cells (CD8), lymphocyte blastogenesis assays, or pokeweed mitogen-induced IgG secretion in T & B cell co-cultures were detected before therapy. A transient lymphopenia following ATG administration was the only immunological defect found in the first month of therapy. At 2 months, however, patients treated with ATG and prednisone had diminished immunoregulatory T cell function demonstrated by production of only 28 +/- 3% IgG expected in T & B co-culture, compared to 205 +/- 35% for untreated IDD patients and 107 +/- 13% for normals (p less than 0.01). This diminished IgG production resulted from excessive suppressor function, since co-cultures of T cells from treated patients with T and B cells from normal volunteers suppressed the latter's IgG production by 76 +/- 9%. This enhanced suppressor activity persisted for 3-6 months following therapy. Other immunological functions were not statistically different from those present at the inception of the study. Thus, treatment with corticosteroids and ATG produces long-term enhanced suppressor activity, a finding which suggests that treatment with combination ATG and Prednisone is a rational form of immunomodulation in conditions associated with decreased suppressor function.
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PMID:Long-term immunoregulatory effects of therapy with corticosteroids and anti-thymocyte globulin. 269 66


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