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)

Insulin-dependent diabetes mellitus (IDDM) is associated with class II molecules of the MHC on chromosome 6, in particular HLA-DR and -DQ alleles, but a pathogenic role for TNF-alpha in the class III region of the MHC has also been implied. We therefore tested whether there was any independent association between a biallelic TNF polymorphism and IDDM. The TNF2 allele was present in 61 of 114 (54%) IDDM patients compared to 101 of 253 (40%) control subjects (odds ratio 1.73; p < 0.02). Stratification analysis in individuals matched for HLA-DR3 revealed, however, that this association was not independent of HLA-DR3 and is most likely to be a result of linkage disequilibrium between these alleles.
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PMID:Comparative analysis of the genetic associations of HLA-DR3 and tumour necrosis factor alpha with human IDDM. 805 88

Insulin-dependent diabetes is an autoimmune disease specifically targeting the pancreatic beta cells and several observations, both experimental and clinical, suggest that the interaction of the immune system with the beta cells is in part determined by the functional state of the target cells, increased beta cell activity resulting in augmented immunologic mechanisms and vice versa for suppressed beta cell activity and decreased immune attack. In this study we investigated whether cytokine induced islet cell cytotoxicity in vitro was in part dependent on the functional state of the beta cells. Cytotoxicity of cultured rat islets was induced by IL-1 (100 pg/ml) and TNF (62.5 ng/ml) individually and in combination and beta cell activity was modulated by culturing the islets in media containing 3.3, 5.5, 11, and 20 mmol/liter glucose. Both IL-1 and TNF were cytotoxic when administered individually and the combination of IL-1 and TNF was more cytotoxic than either cytokine alone. Maximum cytotoxicity was observed at 11 mmol/liter glucose with cytotoxicity being reduced at 5.5 mmol/liter glucose and further reduced at 3.3 mmol/liter glucose. Interestingly, the degree of cytotoxicity was lower in 20 mmol/liter glucose compared to 11 mmol/liter. These results firmly establish that islet cytotoxicity of IL-1 and TNF is highly dependent on the functional state of the beta cells. This suggests that during the IDDM disease process as some beta cells are destroyed, the compensatory increased activity of the remaining beta cells may increase their susceptibility to cytokine attack. Furthermore, our observations provide rational support for the use of beta cell rest as intervention therapy for IDDM.
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PMID:The functional state of the beta cell modulates IL-1 and TNF-induced cytotoxicity. 821 98

There will be a continuing need for well characterized panels of EBV-transformed lymphoblastoid cell lines. Selection of the 4AOH panel was based on prior MHC typing and was intended to ensure representation of ancestral haplotypes from various racial groups. Cells from nonhuman primates, bone marrow donor-recipient pairs, and patients with IDDM were included. Selected cells from the 10IHW were included to enable further characterization. Cells were distributed to participants in the 4AOHW and were typed at multiple loci by a variety of procedures. Non-HLA genes such as TNF were included. Since the cells were distributed "blind" with hidden replicates, it was possible to evaluate the quality of the typing data. An approach to data management is described. The best current estimates of the typing of these cells are presented. The panel will be useful since it provides standards for most alleles at most loci. Since the cells are so well characterized, they represent a useful resource for MHC sequencing and for the evaluation of new typing procedures.
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PMID:Characterization of 4AOHW cell line panel including new data for the 10IHW panel. 830 84

Chimpanzees (Pan Troglodytes) and humans are closely related and belong to the same subfamily, Homininae. The approximately 1.8% genetic difference that exists between humans and the chimpanzees must be responsible for observed differences between these two species. It has been shown that chimpanzees can be infected with HIV, but AIDS has not been reported. Furthermore, the prevalence of autoimmune diseases may be low in this species. For instance, type II diabetes occurs, but type I (autoimmune) diabetes (IDDM), to our knowledge, has not been reported. In humans, susceptibility genes for MG and IDDM have been localized to the region between TNF and HLA-B. This region may also influence the rate of progression to death after HIV infection. We have identified differences in this region between humans and the chimpanzees. As shown by PFGE, the TNF to Patr-B region in the chimpanzees is approximately 130-160 kb shorter than the equivalent in humans. Southern and sequence analyses indicate that the deletions in chimpanzees (insertions in humans) include one copy of CL (approximately 10 kb) and the X sequences (< 30 kb). Obviously, other deletions/insertions (approximately 120 kb) need to be identified. Since CL has been shown to be transcribed, the results imply the lack of the gene or, at least, a different gene copy number in the chimpanzees, and we propose that such differences may be relevant to the observed functional differences. We demonstrate here a strategy to identify critical genes responsible for disease development.
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PMID:Differences in the central major histocompatibility complex between humans and chimpanzees. Implications for development of autoimmunity and acquired immune deficiency syndrome. 830 85

Interleukin-1 (IL-1) has been implicated as an effector in insulitis of Type 1 (insulin-dependent) diabetes. Exposure of a beta-cell line (beta TC1) to IL-1 beta resulted in an increase of preproinsulin mRNA at 0.5 h followed by a gradual decrease. Tumor necrosis factor-alpha (TNF-alpha) mRNA expression by beta TC1 cells was demonstrated 1-3 h after the addition of IL-1 beta. TNF bioactivity was detected in homogenates of beta TC1 cells exposed to IL-1. The supplementation of cycloheximide (CHX) together with IL-1 beta resulted in the superinduction of TNF-alpha mRNA, suggesting that de novo protein synthesis is not required in IL-1-induced TNF-alpha mRNA expression. Endogenous TNF-alpha of beta-cells may be involved in the islet lesion of type 1 diabetes.
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PMID:Interleukin-1 induction of tumor necrosis factor-alpha mRNA and bioactive tumor necrosis factor-alpha in a pancreatic beta-cell line by a mechanism requiring no de novo protein synthesis. 833 33

We have reported previously that chronic and systemic administration of a streptococcal preparation (OK-432), an inducer of TNF, or of recombinant hTNF prevented the development of IDDM in the two animal models of IDDM-NOD mice and BB rats. In this study, we examined the effect of LT, which is structurally and functionally related to TNF, on NOD mice with diabetes. The cumulative incidence of diabetes at 30 wk of age was 22 of 40 (55%) in nontreated female NOD mice and was 4 of 8 (50%; NS), 3 of 29 (10%; P < 0.001), and 0 of 8 (0%; P < 0.001) in female mice treated three times a week from 4 to 30 wk of age with 5, 50, or 500 U of recombinant hLT, respectively. Intensity of insulitis was slightly reduced in the long-term LT-treated mice. LT productivity by ConA-stimulated spleen cells was examined in vitro. Although no significant difference was found between NOD mice and the other mouse strains, female NOD mice were slightly but significantly (P < 0.01) lower producers of LT immunoreactivity than male NOD mice, the diabetes incidence of which is lower than that of females. The SMLR as a marker of normal immune response, which was reported to be impaired in autoimmune animals including NOD mice, was significantly lower in female than male NOD mice. However, the low SMLR in female NOD mice was significantly increased by the administration of LT, and the increase was mediated by the responder cells of the LT-treated mice.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Prevention of autoimmune diabetes with lymphotoxin in NOD mice. 843 10

Insulin dependent diabetes mellitus (IDDM) is an autoimmune disease characterized by lymphocytic infiltration of the pancreatic islets (insulitis). Cytokines released as part of the insulitis process have been suggested to play an important role in the beta cell lesion of IDDM. A possible diabetogenic effect of cytokines may be mediated by their inducing abnormal expression of islet cell autoantigens. Since glutamic acid decarboxylase-65 (GAD-65) is a target autoantigen in IDDM, we investigated whether the cytokines IL-1 beta, TNF alpha IFN gamma altered islet cell expression of GAD-65 and whether the effect of cytokines on GAD-65 expression was similar to their effect on insulin secretion. We found that: 1) IL-1 beta at low dose (1 U/ml) which stimulated insulin secretion, had no effect on GAD-65 expression, whereas higher doses of IL-1 beta (10, 100, 1000 U/ml) which inhibited insulin secretion, decreased GAD-65 expression. 2) TNF alpha at doses of 10, 100, 1000 U/ml which stimulated insulin secretion had no effect on GAD-65 expression. 3) IFN gamma at doses of 10, 100, 1000 U/ml had no effect on insulin secretion or on GAD-65 expression. 4) In combination, IL-1 beta plus TNF alpha and IFN gamma showed a similar inhibitory effect on GAD-65 expression as IL-1 beta alone. In summary: 1) IL-1 beta dramatically inhibits GAD-65 expression. 2) TNF alpha and IFN gamma have no effect on GAD-65 expression. Of these three cytokines, IL-1 beta is the primary cytokine affecting GAD-65 expression.
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PMID:The effect of cytokines on expression of glutamic acid decarboxylase-65 in cultured islets. 878 13

The TNF region within the MHC includes a number of immunologically important genes. Microsatellites TNFa and TNFb adjacent to TNF exhibit extensive polymorphism. Employing a PCR-based technique, we identified TNFab haplotypes and defined their distribution in 97 controls and 48 diabetics of Caucasoid origin in a search for other genes within the MHC potentially associated with IDDM. Twenty-five different TNFab haplotypes were identified. A significant difference (p < 0.0005) in frequency between patients and controls was found for TNFa1b5 (relative risk 53). However, no other TNFab microsatellites demonstrated significantly different frequencies. Among diabetics TNFa1b5 was found to be in linkage disequilibrium with HLA-DR3-B18, a haplotype known to be associated with IDDM. Thus the increased frequency of TNFa1b5 among diabetics could reflect a linkage disequilibrium with a gene within the TNF region or with other genes, including the HLAs, which characterize this haplotype. In both controls and diabetics TNFa2b3 and TNFa7b4 were in linkage disequilibrium with DR3-B8 and DR7, respectively. Among diabetics, TNFa2b1 and TNFa6b5 were in linkage disequilibrium with DR4-B62 and DR4-B44, respectively. It is intriguing that TNFab haplotypes, represented by a short piece of about 200 nucleotides in the untranslated region upstream of TNF beta gene, maintain strong linkage disequilibria with different HLA haplotypes extending over 1 million base pairs. The identification of TNFab microsatellites exhibiting a high polymorphic index in a region lacking known polymorphic markers may provide potentially important information regarding the association of HLA haplotypes with autoimmune diseases, as they are in close proximity to other genes of immunologic importance.
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PMID:Genetic polymorphism of the human tumor necrosis factor region in insulin-dependent diabetes mellitus. Linkage disequilibrium of TNFab microsatellite alleles with HLA haplotypes. 884 31

In vitro, cytokines like interleukin-1-beta (IL-1-B) and tumour necrosis factor-alpha (TNF-A) inhibit insulin release and can destroy islet B-cells. We measured blood levels of IL-1-B, TNF-A, and islet cell antibody (ICA) in 20 children with IDDM, 20 of their non-diabetic siblings, 20 children with thalassemia major on long-term hypertransfusion therapy and iron chelation, and 10 normal age-matched children. In the non-diabetic and thalassemic children we investigated the early phase of insulin release after i.v. glucose (0.5 g/kg, 30 per cent solution) and evaluated tolerance to oral glucose (1.75 g/ kg). Circulating IL-1-B and TNF-A concentrations were significantly higher in IDDM-siblings (33.7 +/- 12.7 pg/ml and 655 +/- 165 pg/ml, respectively) v. normal children (21.1 +/- 6.4 pg/ml and 383 +/- 122 pg/ml, respectively). Thalassemic children had no detectable circulating ICA. The prevalence of ICA was 30 per cent in children with IDDM and 60 per cent of their siblings. Impaired oral glucose tolerance was detected in five children with thalassemia (25 per cent), but in none of the IDDM-siblings. The early phase of insulin release was significantly depressed in thalassemic children (peak insulin = 29.2 +/- 5.1 mIU/ml) v. normal children (52.3 +/- 9.5 mIU/ml) and IDDM-siblings (45.3 +/- 12.4 mIU/ml). It appears that thalassemic children had significantly decreased insulin secretion and impaired glucose tolerance, however, the mechanism of B-cell dysfunction is not mediated by ICA nor by cytokines.
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PMID:Interleukin-1-beta, tumour necrosis factor-alpha, islet-cell antibody, and insulin secretion in children with thalassemia major on long-term blood transfusion. 900 65

The rare HLA-DQB1*0304 allele was found increased among IDDM patients in the populations of the eastern Baltic region. Its frequency among IDDM patients was 4.5% (20/443) compared to 1.1% (9/853) in healthy controls in the combined series of Estonian, Latvian and St. Petersburg Russian populations (P=0.0001). HLA-DQB1*0304 in these populations was associated with DRB1*0408, and the haplotype was further characterized by a B35 allele and a typical combination of microsatellite markers from the TNF gene region. The result is compatible with the significance of the 57th amino acid in the DQ beta-chain but also emphasizes the importance of alleles in other HLA loci adjacent to DQ in the determination of IDDM susceptibility.
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PMID:HLA-DQB1*0304-DRB1*0408 haplotype associated with insulin-dependent diabetes mellitus in populations in the eastern Baltic region. 917 52


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