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)

Prevention of type 1 diabetes in NOD mice by 1,25-dihydroxyvitamin D3 [1alpha,25(OH)2D3] is accompanied by a T-helper (Th) 1/Th2 cytokine shift in the pancreas. The aim of this study was to investigate whether this immune shift also occurs outside of the pancreas and whether it is limited to autoantigen-specific immune responses. NOD mice treated with 1alpha,25(OH)2D3 (5 microg/kg every 2 days) or control vehicle were immunized with GAD65 (p524-543) or ovalbumin (OVA) in the rear footpads. First, we examined T-cell proliferation and cytokine production (via enzyme-linked immunosorbent assay) of draining lymph node cells in vitro with or without peptide rechallenge. Although no differences in proliferation were measured between control and 1alpha,25(OH)2D3-treated mice after in vitro GAD65 rechallenge, a marked shift in cytokine secretion profile was seen in 1alpha,25(OH)2D3-treated mice: interleukin-4 was increased (37 +/- 5 vs. 21 +/- 12 pg/ml in controls, P < 0.005), whereas gamma-interferon levels were decreased (6 +/- 3 vs. 9 +/- 3 ng/ml in controls, P < 0.05). This shift was absent in OVA-primed mice. Second, we measured cytokine profiles by reverse transcriptase-polymerase chain reaction in popliteal lymph nodes at different time points after priming with GAD65 or OVA in vivo. A marked Th1/Th2 shift occurred in 1alpha,25(OH)2D3-treated mice after in vivo priming with GAD65. Again, this shift was absent after OVA immunization. Finally, we measured cytokine profiles after rechallenge with a panel of autoantigens (GAD65, heat shock protein 65, insulin B-chain) and control antigens (OVA, keyhole limpet hemocyanine, myelin proteolipid protein, tetanus toxin) and confirmed the Th1/Th2 shift in autoantigen-injected mice but not in control antigen-injected mice. In conclusion, the immune deviation induced by 1alpha,25(OH)2D3 in NOD mice can also be induced in the peripheral immune system but is limited to pancreatic autoantigens.
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PMID:1alpha,25-dihydroxyvitamin D3 induces an autoantigen-specific T-helper 1/T-helper 2 immune shift in NOD mice immunized with GAD65 (p524-543). 1092 29

The autoimmune diabetic NOD mouse serves as a model for human type 1 diabetes. Disease development is due to islet beta cell destruction in the context of immune cell infiltration of islets and inflammatory changes throughout the pancreas. In the present study we tried to identify immune reactivity patterns in the pancreas associated with diabetes resistance in NOD-related mouse strains. The pancreata of diabetes-prone female NOD/LtJ, NOD/Bom and of genetically related but diabetes-resistant strains; NOR, NON, NON.NOD-H2g7, NOD.NON-H-2nbl were obtained at the age of 70 days for semiquantitative analysis of insulitis and of mRNA expression by reverse transcriptase PCR. In addition, the response to a single dose of cyclophosphamide for synchronizing and accelerating the progression of insulitis was determined. The progression of insulitis and immune gene expression in response to cyclophosphamide revealed characteristic differences between the six strains. NOD/LtJ and NOD/Bom mice were found significantly to upregulate pancreatic IL-12p40 and IL-18 expression after cyclophosphamide treatment, followed by an increase in IFN-gamma mRNA levels. In contrast, the two MHC-haplotype H-2nbl expressing strains either up-regulated neither IL-12/IL-18 nor IFN-gamma gene expression. The two strains sharing MHC haplotype H-2g7 expression with NOD did respond to cyclophosphamide with IL-12p40/IL-18 gene expression. However, NON.NOD-H-2g7 mice failed to progress to IFN-gamma gene expression. NOR mice progressed to IFN-gamma expression but exhibited sustained IL-4 gene expression. Only severe intra-insulitis was associated with the expression of inducible NO synthase. The comparison of diabetes-prone and diabetes-resistant strains revealed three checkpoints of immune regulation in the pancreas. The earliest checkpoint is the induction of an IL-12p40/IL-18 response in innate immune or antigen-presenting cells. The next level of control is at the induction of IFN-gamma gene expression, and a third checkpoint is the maintenance or loss of antagonistic Th2 type reactions.
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PMID:Disease resistant, NOD-related strains reveal checkpoints of immunoregulation in the pancreas. 1140 10

Cytokine-induced beta-cell death is an important event in the pathogenesis of type 1 diabetes. The transcription factor nuclear factor-kappaB (NF-kappaB) is activated by interleukin-1beta (IL-1beta), and its activity promotes the expression of several beta-cell genes, including pro- and anti-apoptotic genes. To elucidate the role of cytokine (IL-1beta + gamma-interferon [IFN-gamma])-induced expression of NF-kappaB in beta-cell apoptosis, rat beta-cells were infected with the recombinant adenovirus AdIkappaB((SA)2), which contained a nondegradable mutant form of inhibitory kappaB (IkappaB((SA)2), with S32A and S36A) that locks NF-kappaB in a cytosolic protein complex, preventing its nuclear action. Expression of IkappaB((SA)2) inhibited cytokine-stimulated nuclear translocation and DNA-binding of NF-kappaB. Cytokine-induced gene expression of several NF-kappaB targets, namely inducible nitric oxide synthase, Fas, and manganese superoxide dismutase, was prevented by AdIkappaB((SA)2), as established by reverse transcriptase-polymerase chain reaction, protein blot, and measurement of nitrite in the medium. Finally, beta-cell survival after IL-1beta + IFN-gamma treatment was significantly improved by IkappaB((SA)2) expression, mostly through inhibition of the apoptotic pathway. Based on these findings, we conclude that NF-kappaB activation, under in vitro conditions, has primarily a pro-apoptotic function in beta-cells.
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PMID:Inhibition of cytokine-induced NF-kappaB activation by adenovirus-mediated expression of a NF-kappaB super-repressor prevents beta-cell apoptosis. 1157 1

Human pancreatic islets are a major focus of diabetes research due to their key role in glucose homeostasis and their potential for transplantation in the treatment of type 1 diabetes. Currently, no comprehensive analysis of baseline or glucose-stimulated islet gene expression is available. Using oligonucleotide microarrays we analyzed isolated intact human islets incubated at low and high glucose. We identified approximately 6000 islet genes, several with clinical implications, as well as a number of glucose-regulated genes. Interestingly, two transforming growth factor beta (TGFbeta) superfamily members were highly regulated by glucose. One of them, PDF, was found to have a very high expression level compared to other TGFbeta superfamily members. Quantitative reverse transcriptase polymerase chain reaction confirmed these results and demonstrated that the highly expressed PDF was approximately 10-fold down- regulated by glucose while other TGFbeta superfamily members and target genes were up-regulated. These results suggest that a highly regulated TGFbeta signaling cascade exists in human islets, and that PDF may play a central role in islet biology. Since TGFbeta is involved in differentiation and immune modulation, this novel pathway may link glucose metabolism, immune response and development of human islets. We report here the first gene expression profile of intact human islets. These and similar analyses will provide better understanding of human islet biology and enhance the development of novel diabetes therapies.
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PMID:Oligonucleotide microarray analysis of intact human pancreatic islets: identification of glucose-responsive genes and a highly regulated TGFbeta signaling pathway. 1219 86

Enterovirus infections have been associated with the manifestation of clinical type 1 diabetes in a number of reports, and recent prospective studies have suggested that enterovirus infections may initiate the autoimmune process, leading to the disease. In the present study, we analyzed the role of enterovirus infections in a Finnish birth cohort study, Diabetes Prediction and Prevention (DIPP), in which all newborn infants are screened for diabetes-associated HLA-DQB1 alleles, and those with an increased genetic risk are invited for prospective follow-up. Enterovirus infections were diagnosed by serology and reverse transcriptase-polymerase chain reaction (RT-PCR) from serum samples taken from birth every 3-6 months. Case children included 41 infants who became positive for diabetes-associated autoantibodies during the observation. Control children comprised altogether 196 infants who remained autoantibody negative and were matched for the time of birth, sex, and HLA-DQB1 alleles. Enterovirus infections were more frequent in case children than in control children (P = 0.004), and the average enterovirus antibody levels were also higher in the case children (P = 0.003). Enterovirus infections were particularly frequent during the 6-month period preceding the first detection of autoantibodies: 51% of the case children compared with 28% of the control children had an infection in that time interval (P = 0.003). There was no difference in the frequency of adenovirus infections between the groups (P = 0.9). The present results imply that enterovirus infections are associated with the appearance of beta-cell autoantibodies. A possible causal relationship is supported by the clustering of infections to the time when autoantibodies appeared.
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PMID:Enterovirus infections are associated with the induction of beta-cell autoimmunity in a prospective birth cohort study. 1243 83

Type 1 diabetes is an autoimmune disease with an inflammatory process directed against the beta cells in pancreas. This investigation aimed at studying the immune response during the first 3 months after the diagnosis of type 1 diabetes, with focus on the balance of T-helper 1 (Th1)- and Th2-like cytokines, produced spontaneously and in response to relevant autoantigens. Peripheral blood mononuclear cells (PBMCs) were collected from type 1 diabetic children (10-17 years) at 5, 20, 35 and 90 days after diagnosis. Expression of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) mRNA were detected by real-time reverse transcriptase polymerase chain reaction and IFN-gamma, IL-10 and IL-13 by enzyme-linked immunosorbent assay in cell supernatant after stimulation with a glutamic acid decarboxylase 65 (GAD(65))-peptide [amino acid (a.a.) 247-279], insulin, the ABBOS-peptide (a.a. 152-169), phytohaemagglutinin and keyhole limpet haemocyanin. Spontaneous and antigen-induced expression and secretion of cytokines were low at the diagnosis of type 1 diabetes. During the first month, after diagnosis, the GAD(65)-peptide caused an increased ratio of IFN-gamma/IL-4 mRNA expression (P < 0.05) and increased secretion of IFN-gamma (P = 0.07). Expression of IFN-gamma mRNA did also increase from stimulation with insulin (P < 0.05), even though cytokine secretion remained low. Thus, duration after diagnosis as well as metabolic state should be carefully considered both in studies of the pathogenesis of type 1 diabetes and in immune intervention studies at onset.
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PMID:Cytokine profile in children during the first 3 months after the diagnosis of type 1 diabetes. 1514 63

The thymus-specific serine protease Prss16 is highly expressed by the epithelial cells in the thymic cortex. It has been suggested to play an important role in the positive selection of T cells through the antigen presention pathway of the cortical antigen presenting cells. Recently, the gene encoding Prss16 has been linked to insulin dependent diabetes mellitus (IDDM) susceptibility independent of HLA-DR3 suggesting the Prss16 may be involved in the development of autoimmune disease. Due to the similarities of the gene structure and expression pattern between the human and mouse genes, we compared Prss16 between non-obese diabetic (NOD) and non-obese non-diabetic (NON) mice. Analysis of the Prss16 coding region failed to identify any differences in sequence. Northern analysis and semi-quantitative reverse transcriptase polymerase chain reaction showed that the mRNA was equal in size and abundance in the two strains. In situ hybridization showed similar patterns of staining. Therefore, our data suggests that there is no significant different in the gene structure, transcription level, and expression pattern of Prss16 gene between NOD and NON mice.
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PMID:Analysis of the IDDM candidate gene Prss16 in NOD and NON mice. 1514 14

Acute rejection after pancreas transplantation remains a significant problem and contributes to immunologic graft loss. No clinical markers of pancreas rejection have been universally accepted. Recent studies have identified several cytotoxic genes as possible markers of acute rejection in renal and islet cell transplant recipients. However, these markers of rejection have not been evaluated in pancreas transplant recipients. This study evaluated the differential expression of granzyme B, perforin, and human leukocyte antigen (HLA)-DRA in peripheral blood between patients with and without biopsy-proven pancreas rejection (n = 7 per group). Gene expression levels were analyzed using real time reverse transcriptase polymerase chain reaction assays. Expression of these genes in controls (n = 17) with and without type 1 diabetes was also analyzed. Patients with biopsy-proven pancreas rejection had higher levels of granzyme B, perforin, and HLA-DRA than patients who did not have rejection, although the difference was not statistically significant. Moreover, patients with biopsy-proven pancreas rejection had a significantly higher level of granzyme B than control subjects with type 1 diabetes (p <or= 0.03). Our findings suggest that, with additional evaluation of a larger number of patients as well as a longitudinal approach, analyses of granzyme B expression levels in peripheral blood may be shown to be a non-invasive method of monitoring pancreas allograft rejection.
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PMID:Correlation of genetic markers of rejection with biopsy findings following human pancreas transplant. 1655 64

Non-obese diabetic (NOD) mice spontaneously develop autoimmune diabetes, and serve as a model for type 1 diabetes (T1D) and natural autoimmunity. T cell responses to the pancreatic islet antigen glutamic acid decarboxylase 65 (GAD65) can be detected in the spleens of young prediabetic NOD mice, which display a unique MHC class II molecule. Here, we report that a distinct TcR beta chain and CDR3 motif are utilized by all NOD mice in response to a dominant determinant on GAD65, establishing a public repertoire in the spontaneous autoimmunity to an important islet cell antigen. GAD65 530-543 (p530)-reactive T cells preferentially utilize the Vbeta4, Dbeta2.1 and Jbeta2.7 gene segments, with a CDR3 that is characterized by a triad of amino acids, DWG, preceded by a polar residue. In addition, we used CDR3 length spectratyping, CDR3-specific reverse transcriptase-PCR and direct TcR sequencing to show that the TcR beta chain structural patterns associated with p530-specific T cells consistently appeared in the islets of young NOD mice with insulitis, but not in the inflamed islets of streptozotocin-treated C57BL/6 mice, or in inflamed NOD salivary glands. To our knowledge, this is the first report to demonstrate that a public T cell repertoire is used in spontaneous autoimmunity to a dominant self-determinant. These findings suggest that defined clonotypes and repertoires may be preferentially selected in haplotypes predisposed to spontaneous autoimmunity.
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PMID:T cells to a dominant epitope of GAD65 express a public CDR3 motif. 1664 Nov 12

Beta-cell replacement therapy by pancreatic islet transplantation has become a promising treatment for type 1 diabetes. However, the limited supply of human islet tissue prevents this therapy from being widely used to treat patients with type 1 diabetes. In order to obtain insulin-secreting cells, retrovirus vector pLNCX was used to transfer the human insulin gene into human bone marrow mesenchymal stem cells (hMSCs). The hMSCs were isolated from bone marrow of healthy volunteers and were expanded in vitro. The reverse transcriptase-polymerase chain reaction (RT-PCR) was used to amplify the insulin DNA fragment from a healthy pancreas sample. The recombinant vector pLNCX-Ins was constructed by cloning the insulin DNA fragment into retrovirus vector pLNCX. After being packaged by BD RetroPack PT67 packaging cells, the virus that contained the insulin gene was used to infect hMSCs. Transcription and expression of the insulin gene in transfected hMSCs were examined by RT-PCR and immunofluorescence. The transfected hMSCs stably secreted insulin into culture media for >3 weeks. Thus, insulin gene-transfected hMSCs can secrete insulin and provide a new way to cope with the shortage of beta cells for therapy of type 1 diabetes.
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PMID:Human bone marrow mesenchymal stem cells transfected with human insulin genes can secrete insulin stably. 1668 7


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