| 1. |
- Ahlgren, Kerstin. M, et al.
(författare)
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Diabetes mellitus in dog - : No evidence for a type-1-like phenotype
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Aims/hypothesis Diabetes mellitus (DM) is one of the most common endocrine disorders in dogs, and is commonly proposed to be of autoimmune origin. Although the clinical symptoms of human type 1 diabetes (T1D) and canine DM are similar, the aetiologies may differ. The aim of this study was to investigate if autoimmune aetiology resembling human T1D is as prevalent in dogs as previously reported. Methods Sera from 121 diabetic dogs representing 38 different breeds were tested for islet cell antibodies (ICA) and GAD65 autoantibodies (GADA) and compared with sera from 133 healthy dogs from 40 breeds. ICA was detected by indirect immunofluorescence using both canine and human frozen sections. GADA was detected by in vitro transcription and translation (ITT) of human and canine GAD65, followed by immunoprecipitation. Results None of the canine sera analyzed tested positive for ICA on sections of frozen canine or human ICA pancreas. However, serum from one diabetic dog was weakly positive in the canine GADA assay and serum from one healthy dog was weakly positive in the human GADA assay. Conclusions/interpretations Based on sera from 121 diabetic dogs from 38 different breeds were tested for humoral autoreactivity using four different assays, contrary to previous observations, we find no support for an autoimmune aetiology in canine diabetes.
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| 2. |
- Ahlgren, Kerstin M, et al.
(författare)
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Lack of evidence for a role of islet autoimmunity in the aetiology of canine diabetes mellitus
- 2014
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Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9:8, s. e105473-
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Tidskriftsartikel (refereegranskat)abstract
- AIMS/HYPOTHESIS:Diabetes mellitus is one of the most common endocrine disorders in dogs and is commonly proposed to be of autoimmune origin. Although the clinical presentation of human type 1 diabetes (T1D) and canine diabetes are similar, the aetiologies may differ. The aim of this study was to investigate if autoimmune aetiology resembling human T1D is as prevalent in dogs as previously reported.METHODS:Sera from 121 diabetic dogs representing 40 different breeds were tested for islet cell antibodies (ICA) and GAD65 autoantibodies (GADA) and compared with sera from 133 healthy dogs. ICA was detected by indirect immunofluorescence using both canine and human frozen sections. GADA was detected by in vitro transcription and translation (ITT) of human and canine GAD65, followed by immune precipitation. Sections of pancreata from five diabetic dogs and two control dogs were examined histopathologically including immunostaining for insulin, glucagon, somatostatin and pancreas polypeptide.RESULTS:None of the canine sera analysed tested positive for ICA on sections of frozen canine or human ICA pancreas. However, serum from one diabetic dog was weakly positive in the canine GADA assay and serum from one healthy dog was weakly positive in the human GADA assay. Histopathology showed marked degenerative changes in endocrine islets, including vacuolisation and variable loss of immune-staining for insulin. No sign of inflammation was noted.CONCLUSIONS/INTERPRETATIONS:Contrary to previous observations, based on results from tests for humoral autoreactivity towards islet proteins using four different assays, and histopathological examinations, we do not find any support for an islet autoimmune aetiology in canine diabetes mellitus.
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| 3. |
- Jensen, Richard A., et al.
(författare)
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Multiple factors affect the loss of measurable C-peptide over 6 years in newly diagnosed 15- to 35-year-old diabetic subjects
- 2007
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Ingår i: Journal of diabetes and its complications. - : Elsevier BV. - 1056-8727 .- 1873-460X. ; 21:4, s. 205-213
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The aim of this study is to identify risk factors for the loss of measurable plasma C-peptide in newly diagnosed 15- to 35-year-old diabetic subjects. Methods: This Swedish study included 778 subjects. C-peptide levels were obtained each year for 6 years after diagnosis. Loss of measurable C-peptide was defined as a level at or below the lower detection limit of the local assay (0.13 nmol/l). In addition to C-peptide, other baseline covariates included gender, age, body mass index, HLA genotype, and autoantibody levels. Results: Compared with autoantibody-negative subjects, autoantibody-positive subjects had lower median baseline C-peptide (0.27 vs. 0.50, P<001), their levels declined over the study period, and the risk of losing measurable C-peptide was significantly higher when more than one autoantibody was present [odds ratio (OR), 4.0; 95% confidence interval (CI), 2.13-7.54]. Among autoantibody-positive individuals, the presence of GAD65Ab (OR, 1.8; 95% Cl, 1.24-2.51) and islet cell antibodies (OR, 1.6; 95% CI, 1.19-2.18) conferred a higher risk for loss of measurable C-peptide as did female gender (OR, 1.6; 95% CI, 1.17-2.11) and time after diagnosis (OR, 1.5 for each additional year postdiagnosis; 95% CI, 1.41-1.57). Higher baseline C-peptide levels were protective (OR, 0.5 for each additional log nanomoles per liter; 95% CI, 0.36-0.58). Conclusions: This study identified autoantibody status, gender, and baseline C-peptide levels as factors that will be useful for predicting the disease course of 15- to 35-year-old diabetic individuals.
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| 4. |
- Jensen, R., et al.
(författare)
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Islet cell autoantibody levels after the diagnosis of young adult diabetic patients
- 2007
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Ingår i: Diabetic Medicine. - : Wiley. - 0742-3071 .- 1464-5491. ; 24:11, s. 1221-1228
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Tidskriftsartikel (refereegranskat)abstract
- Aims The aim was to determine the course of islet cell antibodies [glutamate decarboxylase (GADA), tyrosine phosphatase-like islet antigen 2 (IA-2A) and islet cell (ICA)] after the diagnosis of the diabetic patient. Methods The Diabetes Incidence Study in Sweden (DISS) attempted to prospectively enrol all newly diagnosed diabetic patients aged 15–34 years during 1992 and 1993. C-peptide and autoantibody levels were determined from venous blood samples at diagnosis and again at yearly intervals for 6 years. Results After the first year, the odds of remaining GADA positive decreased by 9% per year [odds ratio (OR) = 0.91, 95% confidence interval (CI) = 0.85–0.96] while the mean GADA index remained unchanged ( = 0.8, P = 0.37). There was no change in the percentage of subjects testing IA-2A positive after the first year ( = 0.1, P = 0.75). However, the mean index decreased 0.04 per year (95% CI: 0.03–0.05)—a 7.9% decline (95% CI: 5.4–10.4%). The odds of a subject testing positive for ICA decreased by 24% per year (OR = 0.76, 95% CI = 0.70–0.82). The mean ICA levels decreased 0.75 per year (95% CI: 0.66–0.84)—a 16.4% decline (95% CI: 14.1–18.6%). The rate of change in titres for all three autoantibodies was independent of gender, human leucocyte antigen genotype and C-peptide status. Conclusions GADA levels remained high while ICA levels declined. In contrast to a previous study, we found that the proportion of IA-2A subjects remaining positive did not decrease after the first year, while the average index decreased slightly.
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| 5. |
- Agardh, Daniel, et al.
(författare)
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Autoantibodies Against Soluble and Immobilized Human Recombinant Tissue Transglutaminase in Children with Celiac Disease.
- 2005
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Ingår i: Journal of Pediatric Gastroenterology and Nutrition - Jpgn. - : Ovid Technologies (Wolters Kluwer Health). - 1536-4801 .- 0277-2116. ; 41:3, s. 322-327
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: The conformation of tissue transglutaminase might influence the performance of immunoassays to detect autoantibodies from patients with celiac disease. The present study investigated how the exposure of tissue transglutaminase kept in a liquid phase and fixed to a solid support affected the binding of immunoglobulin (Ig)A and IgG autoantibodies in children with untreated and treated celiac disease. Methods: Included were 73 untreated celiac disease children, 50 controls and 80 children with treated celiac disease. IgA and IgG antitissue transglutaminase were measured with solid phase enzyme-linked immunoassay (ELISA) and liquid phase radioligand binding assays. For IgG antitissue transglutaminase detection with radioligand binding assays antihuman IgG and protein A were used. IgA endomysial autoantibodies were measured by indirect immunofluorescence. Results: Both ELISA and radioligand binding assays detected IgA antitissue transglutaminase in 65 of 73 untreated celiac disease children and in 2 of 50 controls. One additional control child was detected with radioligand binding assays. Endomysial autoantibodies were present in 62 of 73 celiac disease children and in 2 of 50 controls. IgG antitissue transglutaminase was detected with both ELISA and radioligand binding assays in 40 of 73 untreated celiac disease children and in 2 of 50 controls. Radioligand binding assays using protein A detected 20 of 73 additional untreated celiac disease children and one control child with increased IgG antitissue transglutaminase. In treated celiac disease children, 21 of 80 were IgA antitissue transglutaminase positive with radioligand binding assays, 3 of 80 with ELISA, whereas none had endomysial autoantibodies. Conclusions: No qualitative differences between radioligand binding assays and ELISA in IgA or IgG antitissue transglutaminase binding from untreated celiac disease children was demonstrated. However, discrepancies in the binding of IgA antitissue transglutaminase from a subgroup of treated celiac disease children indicated that alterations of tissue transglutaminase might occur on fixation of the antigen. Protein A used for radioligand binding assays seemed not to assess IgG autoantibodies exclusively. IgA antitissue transglutaminase detection in screening of childhood celiac disease can be performed either by ELISA or radioligand binding assays because the two assays are interchangeable.
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| 6. |
- Ahlqvist, Emma, et al.
(författare)
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Novel subgroups of adult-onset diabetes and their association with outcomes : a data-driven cluster analysis of six variables
- 2018
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Ingår i: The Lancet Diabetes and Endocrinology. - 2213-8587 .- 2213-8595. ; 6:5, s. 361-369
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundDiabetes is presently classified into two main forms, type 1 and type 2 diabetes, but type 2 diabetes in particular is highly heterogeneous. A refined classification could provide a powerful tool to individualise treatment regimens and identify individuals with increased risk of complications at diagnosis.MethodsWe did data-driven cluster analysis (k-means and hierarchical clustering) in patients with newly diagnosed diabetes (n=8980) from the Swedish All New Diabetics in Scania cohort. Clusters were based on six variables (glutamate decarboxylase antibodies, age at diagnosis, BMI, HbA1c, and homoeostatic model assessment 2 estimates of β-cell function and insulin resistance), and were related to prospective data from patient records on development of complications and prescription of medication. Replication was done in three independent cohorts: the Scania Diabetes Registry (n=1466), All New Diabetics in Uppsala (n=844), and Diabetes Registry Vaasa (n=3485). Cox regression and logistic regression were used to compare time to medication, time to reaching the treatment goal, and risk of diabetic complications and genetic associations.FindingsWe identified five replicable clusters of patients with diabetes, which had significantly different patient characteristics and risk of diabetic complications. In particular, individuals in cluster 3 (most resistant to insulin) had significantly higher risk of diabetic kidney disease than individuals in clusters 4 and 5, but had been prescribed similar diabetes treatment. Cluster 2 (insulin deficient) had the highest risk of retinopathy. In support of the clustering, genetic associations in the clusters differed from those seen in traditional type 2 diabetes.InterpretationWe stratified patients into five subgroups with differing disease progression and risk of diabetic complications. This new substratification might eventually help to tailor and target early treatment to patients who would benefit most, thereby representing a first step towards precision medicine in diabetes.
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| 7. |
- Andersson, Cecilia K, et al.
(författare)
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Glucose tolerance and beta-cell function in islet autoantibody-positive children recruited to a secondary prevention study.
- 2013
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Ingår i: Pediatric Diabetes. - : Hindawi Limited. - 1399-543X .- 1399-5448. ; 14:5, s. 341-349
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Tidskriftsartikel (refereegranskat)abstract
- AIMS: Children with type 1 diabetes (T1D) risk and islet autoantibodies are recruited to a secondary prevention study. The aims were to determine metabolic control in relation to human leukocyte antigen (HLA) genetic risk and islet autoantibodies in prepubertal children. METHODS: In 47 healthy children with GADA and at least one additional islet autoantibody, intravenous glucose tolerance test (IvGTT) and oral glucose tolerance test (OGTT) were performed 8-65 d apart. Hemoglobin A1c, plasma glucose as well as serum insulin and C-peptide were determined at fasting and during IvGTT and OGTT. RESULTS: All children aged median 5.1 (4.0-9.2) yr had autoantibodies to two to six of the beta-cell antigens GAD65, insulin, IA-2, and the three amino acid position 325 variants of the ZnT8 transporter. In total, 20/47 children showed impaired glucose metabolism. Decreased (≤30 μU/mL insulin) first-phase insulin response (FPIR) was found in 14/20 children while 11/20 had impaired glucose tolerance in the OGTT. Five children had both impaired glucose tolerance and FPIR ≤30 μU/mL insulin. Number and levels of autoantibodies were not associated with glucose metabolism, except for an increased frequency (p = 0.03) and level (p = 0.01) of ZnT8QA in children with impaired glucose metabolism. Among the children with impaired glucose metabolism, 13/20 had HLA-DQ2/8, compared to 9/27 of the children with normal glucose metabolism (p = 0.03). CONCLUSION: Secondary prevention studies in children with islet autoantibodies are complicated by variability in baseline glucose metabolism. Evaluation of metabolic control with both IvGTT and OGTT is critical and should be taken into account before randomization. All currently available autoantibody tests should be analyzed, including ZnT8QA.
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| 8. |
- Andersson, C, et al.
(författare)
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Triple specificity of ZnT8 autoantibodies in relation to HLA and other islet autoantibodies in childhood and adolescent type 1 diabetes
- 2013
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Ingår i: Pediatric Diabetes. - : Wiley-Blackwell. - 1399-543X .- 1399-5448. ; 14:2, s. 97-105
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Tidskriftsartikel (refereegranskat)abstract
- Andersson C, Vaziri-Sani F, Delli AJ, Lindblad B, Carlsson A, Forsander G, Ludvigsson J, Marcus C, Samuelsson U, Ivarsson SA, Lernmark A, Elding Larsson H, the BDD Study group. Triple specificity of ZnT8 autoantibodies in relation to HLA and other islet autoantibodies in childhood and adolescent type 1 diabetes. Pediatric Diabetes 2013: 14: 97-105. Objective To establish the diagnostic sensitivity of and the relationships between autoantibodies to all three Zinc transporter 8 (Zinc transporter 8 autoantibody to either one, two, or all three amino acid variants at position 325, ZnT8A) variants to human leukocyte antigen (HLA)-DQ and to autoantibodies to glutamic acid decarboxylase (GADA), insulinoma-associated protein 2 (IA-2A), and insulin (IAA). Methods We analyzed 3165 patients with type 1 diabetes (T1D) in the Better Diabetes Diagnosis study for HLA-DQ genotypes and all six autoantibodies (ZnT8RA, arginine 325 Zinc transporter 8 autoantibody; ZnT8WA, tryptophan 325 Zinc transporter 8 autoantibody; ZnT8QA, glutamine 325 Zinc transporter 8 autoantibody; GADA, IA-2A, and IAA). Results ZnT8A was found in 65% of the patients and as many as 108 of 3165 (3.4%) had 13 ZnT8A alone. None had ZnT8QA alone. Together with GADA (56%), IA-2A (73%), and IAA (33%), 93% of the T1D patients were autoantibody positive. All three ZnT8A were less frequent in children below 2 yr of age (pandlt;0.0001). All three ZnT8A were associated with DQA1-B1*X-0604 (DQ6.4) and DQA1-B1*03-0302 (DQ8). ZnT8WA and ZnT8QA were negatively associated with DQA1-B1*05-02 (DQ2). Conclusions Analysis of ZnT8A increased the diagnostic sensitivity of islet autoantibodies for T1D as only 7% remained islet autoantibody negative. The association between DQ6.4 and all three ZnT8A may be related to ZnT8 antigen presentation by the DQ6.4 heterodimer.
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| 9. |
- de Oliveira, Felipe, 1984-, et al.
(författare)
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Autoimmunity detection via proximity assays
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Since autoantibodies are recognized as valuable biomarkers for clinical diagnostics and prognostics in autoimmune diseases such as Stiff Person Syndrome (SPS) and Type 1 diabetes, detection of such markers at improved sensitivity and specificity could be of significant interest. In addition, as proximity assays have been shown to offer highly sensitive and specific detection of multiple proteins, the technique could be expanded to applications for autoimmunity detection. In the present study, we have applied the newly developed proximity ligation assay with rolling circle amplification (PLARCA), and proximity extension assay (PEA) for the detection of GADA, autoantibodies specific for glutamic acid decarboxylase 65 (GAD65). Through the use of oligonucleotide conjugated autoantigen GAD65 and anti-human antibodies, as proximity probes, we were able to apply these proximity assays to detect GADA in a set of SPS patient samples. In summary, we have applied and established both PLARCA and PEA, as a proof of concept, for the use of the specific and sensitive autoimmune detection.
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| 10. |
- Elfving, Maria, et al.
(författare)
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Maternal enterovirus infection during pregnancy as a risk factor in Offspring Diagnosed with Type 1 Diabetes between 15 and 30 years of age
- 2008
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Ingår i: Experimental Diabetes Research. - : Hindawi Limited. - 1687-5214 .- 1687-5303. ; , s. 271958-
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Tidskriftsartikel (refereegranskat)abstract
- Maternal enterovirus infections during pregnancy may increase the risk of offspring developing type 1 diabetes during childhood. The aim of this study was to investigate whether gestational enterovirus infections increase the offspring's risk of type 1 diabetes later in life. Serum samples from 30 mothers without diabetes whose offspring developed type 1 diabetes between 15 and 25 years of age were analyzed for enterovirus-specific immunoglobulin M (IgM) antibodies and enterovirus genome (RNA), and compared to a control group. Among the index mothers, 9/30 (30%) were enterovirus IgM-positive, and none was positive for enterovirus RNA. In the control group, 14/90 (16%) were enterovirus IgM-positive, and 4/90 (4%) were positive for enterovirus RNA (n.s.). Boys of enterovirus IgM-positive mothers had approximately 5 times greater risk of developing diabetes (OR 4.63; 95% CI 1.22-17.6), as compared to boys of IgM-negative mothers (P < .025). These results suggest that gestational enterovirus infections may be related to the risk of offspring developing type 1 diabetes in adolescence and young adulthood.
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