| 1. |
- Jensen, Richard A., et al.
(författare)
-
Multiple factors affect the loss of measurable C-peptide over 6 years in newly diagnosed 15- to 35-year-old diabetic subjects
- 2007
-
Ingår i: Journal of diabetes and its complications. - : Elsevier BV. - 1056-8727 .- 1873-460X. ; 21:4, s. 205-213
-
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.
|
|
| 2. |
- Jensen, R., et al.
(författare)
-
Islet cell autoantibody levels after the diagnosis of young adult diabetic patients
- 2007
-
Ingår i: Diabetic Medicine. - : Wiley. - 0742-3071 .- 1464-5491. ; 24:11, s. 1221-1228
-
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.
|
|
| 3. |
- Agardh, Daniel, et al.
(författare)
-
HLA-DQB1*0201/0302 is associated with severe retinopathy in patients with IDDM
- 1996
-
Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 1432-0428 .- 0012-186X. ; 39:11, s. 1313-1317
-
Tidskriftsartikel (refereegranskat)abstract
- Some insulin-dependent diabetic (IDDM) patients develop severe forms of retinopathy. Putative risk factors such as hypertension, poor metabolic control, nephropathy and growth hormone levels do not fully explain the progress of retinopathy in these patients. It has been discussed whether there is a genetic marker, since some diabetic patients without any known predisposing risk factors develop severe retinopathy and others do not. In the present study, HLA-DR and DQ were compared in two patient groups with IDDM. One group consisted of patients with early-onset diabetes, with severe non-proliferative or proliferative retinopathy; the other group had no or only mild signs of retinopathy. High resolution HLA typing was carried out by polymerase chain reaction (PCR) and hybridization with allele specific probes. Alleles on the DR3-DQ2 haplotype, DRB1*0301, DQA1*0501 and DQB1*0201, were more frequent in patients with severe retinopathy. A difference was seen when combining certain alleles in the genotypes of DQA1*03/0501 (p > 0.05) and DQB1*0201/0302 (p < 0.01). The findings of the present study suggest that DQB1*0201/0302 is the strongest genetic marker for severe retinopathy and DRB1*0301/0401 only has a secondary influence when combined with this genotype. It seems as if IDDM patients who are positive for the genotype DR3-DQ2/DR4-DQ8 (DRB1*0301-DQA1*0501-DQB1*0201/DRB1*0401 -DQA1*03-DQB1*0302) are at greater risk of developing severe retinopathy.
|
|
| 4. |
- Agardh, Daniel, et al.
(författare)
-
Inverse relationship between GAD65 antibody levels and severe retinopathy in younger type 1 diabetic patients
- 1998
-
Ingår i: Diabetes Research and Clinical Practice. - 1872-8227. ; 40:1, s. 9-14
-
Tidskriftsartikel (refereegranskat)abstract
- Several risk factors for severe non-proliferative and proliferative retinopathy in type 1 diabetes mellitus have been proposed without explaining the rapid progression of retinopathy in some patients. Since GAD65 autoantibodies (GAD65Abs) are detected against glutamic acid decarboxylase (GAD), which is mainly expressed in islets and nervous tissue in type 1 diabetic patients, the aim of the present investigation was to test the hypothesis whether GAD65Abs are associated with rapidly progressing severe retinopathy. Patients with severe non-proliferative or proliferative retinopathy (n = 27) were compared with another group, which in spite of long diabetes duration had no or only mild signs of retinopathy (n = 28). GAD65Abs were analysed in a radioimmunoassay using in vitro translated human GAD65, and the levels were expressed as an index in relation to positive and negative reference samples. Using a cut-off level representing the 99th percentile of normals, 6/27 (22%) with and 9/28 (32%) without severe retinopathy were considered GAD65Ab positive. Although there was no difference in the number of GAD65Ab positive patients, the GAD65Ab levels were lower in patients with (0.30; 0.11-0.64) than without (0.68; 0.34-1.12) severe retinopathy (P = 0.03). The patients were also subjected to HLA-DR and DQ typing by PCR and hybridization with oligospecific probes. DQ2/8 was more common in patients with (56%) than without (29%) severe retinopathy (P = 0.05), but DQ2/8 could not account for the lower GAD65Ab levels in patients with severe retinopathy. It is concluded that GAD65Ab levels are inversely correlated with severe retinopathy in young type 1 diabetic patients.
|
|
| 5. |
- Graham, J, et al.
(författare)
-
Genetic effects on age-dependent onset and islet cell autoantibody markers in type 1 diabetes
- 2002
-
Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 51:5, s. 1346-1355
-
Tidskriftsartikel (refereegranskat)abstract
- Age-dependent associations between type 1 diabetes risk genes HLA, INS VNTR, and CTLA-4 and autoantibodies to GAD65 (GADAs), ICA512/IA-2, insulin, and islet cells were determined by logistic regression analysis in 971 incident patients with type 1 diabetes and 702 control subjects aged 0–34 years. GADAs were associated with HLA-DQ2 in young but not in older patients (P = 0.009). Autoantibodies to insulin were negatively associated with age (P < 0.0001) but positively associated with DQ8 (P = 0.03) and with INS VNTR (P = 0.04), supporting possible immune tolerance induction. ICA512/IA-2 were negatively associated with age (P < 0.0001) and with DQ2 (P < 0.0001) but positively associated with DQ8 (P = 0.04). Males were more likely than females to be negative for GADA (P < 0.0001), autoantibodies to islet cells (P = 0.04), and all four autoantibody markers (P = 0.004). The CTLA-4 3′ end microsatellite marker was not associated with any of the autoantibodies. We conclude that age and genetic factors such as HLA-DQ and INS VNTR need to be combined with islet autoantibody markers when evaluating the risk for type 1 diabetes development.
|
|
| 6. |
- Graham, Jinko, et al.
(författare)
-
Negative association between type 1 diabetes and HLA DQB1*0602-DQA1*0102 is attenuated with age at onset
- 1999
-
Ingår i: European Journal of Immunogenetics. - : Wiley. - 0960-7420 .- 1365-2370. ; 26, s. 117-
-
Tidskriftsartikel (refereegranskat)abstract
- HLA-associated relative risks of type 1 (insulin-dependent) diabetes mellitus were analysed in population-based Swedish patients and controls aged 0-34 years. The age dependence of HLA-associated relative risks was assessed by likelihood ratio tests of regression parameters in separate logistic regression models for each HLA category. The analyses demonstrated an attenuation with increasing age at onset in the relative risk for the positively associated DQB1*0201-A1*0502/B1*0302-A1*0301 (DQ2/8) genotype (P = 0.02) and the negatively associated DQB1*0602-A1*0102 (DQ6.2) haplotype (P = 0.004). At birth, DQ6.2-positive individuals had an estimated relative risk of 0.03, but this increased to 1.1 at age 35 years. Relative risks for individuals with DQ genotype 8/8 or 8/X or DQ genotype 2/2 or 2/X, where X is any DQ haplotype ether than 2, 8 or 6.2, were not significantly age-dependent. An exploratory analysis of DQ haplotypes other than 2, 8 and 6.2 suggested that the risk of type 1 diabetes increases with age for DQB1*0604-A1*0102 (DQ6.4) and that the peak risk for the negatively associated DQB1*0301-A1*0501 haplotype is at age 18 years. There was also weak evidence that the risk for DQB1*0303-A1*0301 (DQ9), which has a positive association in the Japanese population, may decrease with age. We speculate that HLA-DQ alleles have a significant effect on the rate of beta cell destruction, which is accelerated in DQ2/8-positive individuals and inhibited, but not completely blocked, in DQ6.2-positive individuals.
|
|
| 7. |
- Gupta, Manu, et al.
(författare)
-
Association between the transmembrane region polymorphism of MHC class I chain related gene-A and type 1 diabetes mellitus in Sweden
- 2003
-
Ingår i: Human Immunology. - 0198-8859. ; 64:5, s. 553-561
-
Tidskriftsartikel (refereegranskat)abstract
- Major histocompatibility complex (MHC) class I chain related gene-A (MIC-A) is associated with type 1 diabetes mellitus (T1DM) in other populations. We tested the association of MIC-A gene polymorphism with T1DM in Swedish Caucasians; if it has an age-dependent association; and if the association has an effect on gender. We studied 635 T1DM patients and 503 matched controls in the age group of 0-35 years old. MIC-A5 was significantly increased in T1DM compared with controls (odds ratio [OR] =1.81, p(c) < 0.0005). Logistic regression analysis revealed MIC-A5 association was independent of HLA. MIC-A5 with DR4-DQ8 or MIC-A5 with DR3-DQ2 gave higher OR than the OR obtained with either of them alone (OR = 1.81, 7.1, and 3.6, respectively). MIC-A5 was positively (OR = 2.48, p(c) < 0.0005) and MIC-A6 negatively associated (OR = 0.61, p(c) = 0.035) with the disease in less than or equal to 20 years of age. The negative association of MIC-A6 in young onset was confirmed by logistic regression analysis. MIC-A5 was associated with the disease in males (OR = 2.05, p(c) = 0.0005). MIC-A6 conferred protection (OR = 0.098, p(c) = 0.032) in females heterozygous for DR3/DR4. In conclusion, MIC-A5 is associated with T1DM; the association was higher in individuals less than or equal to 20 years old; and negative association of MIC-A6 was stronger in younger onset patients than in older onset patients.
|
|
| 8. |
- Gupta, Manu, et al.
(författare)
-
MHC class I chain-related gene-A is associated with IA2 and IAA but not GAD in Swedish type 1 diabetes mellitus
- 2006
-
Ingår i: Annals of the New York Academy of Sciences. - : Wiley. - 0077-8923. ; 1079, s. 229-239
-
Tidskriftsartikel (refereegranskat)abstract
- In type I diabetes mellitus (T1DM), the frequency of antibodies against insulin (IAA), glutamic acid decarboxylase-65 (GAD65), ICA512/IA2 (IA2), and islet cell antigens (ICA) vary with human leukocyte antigen (HLA) composition of the patient. IAA, IA2 autoantibodies, and ICA are increased in DQ8 positives; GAD65 antibodies are increased in DQ2 positives. MHC class I chain-related gene-A (MICA) is another genetic marker that has been proposed to be associated with T1DM. In this article, we looked at microsatellite polymorphism of MICA and its association with autoantibodies (IAA, IA2, and GAD65) in Swedish T1DM patients and if the association explains its importance in early events in autoimmune response. We studied 635 T1DM patients between 0-35 years. Frequency of MICA5/5 was positively associated with the formation of IAA and IA2 antibodies considered individually or in combination (odds ratio 10111, 95% Cl, Pc: [IAA+ versus IAA-] : 4.94, 2.09-11.62, < 0.0005; [IA2+ versus IA2-] : 2.65,1.52-4.59,0.0015; [IAA and/or IA2+ versus rest]: 9.83, 2.37-40.78, < 0.0015; [IAA and IA2+ versus rest]: 3.51, 2.01-6.15, < 0.0015). Also, -5.115.1 was increased in IAA+ patients compared to IAA- patients (2.82, 1.64-4.83, < 0.0005). All patients positive for -5/5 developed at least one of the three antibodies. Frequency of MICA5.1 was decreased in IAA+ (0.54, 0.36-0.81, 0.017), in IA2A+ (0.63, 0.45-0.88, 0.04), in IAA and/or IA2A+ (0.52, 0.33-0.84, 0.044), and in IAA and IA2A+ (0.55, 0.39-0.78, 0.0055) patients when compared with patients negative for corresponding antibodies. Frequency of MICA9, 5/5.1, and 5.1/9 was decreased in IAA+ compared to IAA- patients (0.51, 0.32-0.79,0.021; 0.22, 0.11-0.44, < 0.005; and 0.39, 0.22-0.69, 0.026, respectively). Frequency of MICA9 and -5.1/9 was also decreased in IAA and/or IA2 antibody-positive patients while MICA5/5.1 decreased in patients positive for IAA and IA2 antibody both together. IAA and IA2 antibodies are believed to appear early during the autoimmune reaction against beta cells. Thus, according to our data, MICA-5/5 and -5.1/5.1 is associated with early autoimmunity in T1DM patients. Our study suggests that MICA gene polymorphism is associated with autoantibody formation and that the polymorphism especially MICA5/5 and -5.1/5.1 are important in early events of autoimmune reaction.
|
|
| 9. |
- Gyllenberg, A, et al.
(författare)
-
Age-dependent variation of genotypes in MHC II transactivator gene (CIITA) in controls and association to type 1 diabetes
- 2012
-
Ingår i: Genes and Immunity. - Stockholm : Springer Science and Business Media LLC. - 1476-5470 .- 1466-4879. ; 76:2, s. 202-203
-
Tidskriftsartikel (refereegranskat)abstract
- The major histocompatibility complex class II transactivator (CIITA) gene (16p13) has been reported to associate with susceptibility to multiple sclerosis, rheumatoid arthritis and myocardial infarction, recently also to celiac disease at genome-wide level. However, attempts to replicate association have been inconclusive. Previously, we have observed linkage to the CIITA region in Scandinavian type 1 diabetes (T1D) families. Here we analyze five Swedish T1D cohorts and a combined control material from previous studies of CIITA. We investigate how the genotype distribution within the CIITA gene varies depending on age, and the association to T1D. Unexpectedly, we find a significant difference in the genotype distribution for markers in CIITA (rs11074932, P=4 × 10(-5) and rs3087456, P=0.05) with respect to age, in the collected control material. This observation is replicated in an independent cohort material of about 2000 individuals (P=0.006, P=0.007). We also detect association to T1D for both markers, rs11074932 (P=0.004) and rs3087456 (P=0.001), after adjusting for age at sampling. The association remains independent of the adjacent T1D risk gene CLEC16A. Our results indicate an age-dependent variation in CIITA allele frequencies, a finding of relevance for the contrasting outcomes of previously published association studies.
|
|
| 10. |
- Gyllenberg, A, et al.
(författare)
-
Variability in the CIITA gene interacts with HLA in multiple sclerosis.
- 2014
-
Ingår i: Genes and immunity. - Stockholm : Springer Science and Business Media LLC. - 1476-5470 .- 1466-4879. ; 15, s. 162-167
-
Tidskriftsartikel (refereegranskat)abstract
- The human leukocyte antigen (HLA) is the main genetic determinant of multiple sclerosis (MS) risk. Within the HLA, the class II HLA-DRB1*15:01 allele exerts a disease-promoting effect, whereas the class I HLA-A*02 allele is protective. The CIITA gene is crucial for expression of class II HLA molecules and has previously been found to associate with several autoimmune diseases, including MS and type 1 diabetes. We here performed association analyses with CIITA in 2000 MS cases and up to 6900 controls as well as interaction analysis with HLA. We find that the previously investigated single-nucleotide polymorphism rs4774 is associated with MS risk in cases carrying the HLA-DRB1*15 allele (P=0.01, odds ratio (OR): 1.21, 95% confidence interval (CI): 1.04-1.40) or the HLA-A*02 allele (P=0.01, OR: 1.33, 95% CI: 1.07-1.64) and that these associations are independent of the adjacent confirmed MS susceptibility gene CLEC16A. We also confirm interaction between rs4774 and HLA-DRB1*15:01 such that individuals carrying the risk allele for rs4774 and HLA-DRB1*15:01 have a higher than expected risk for MS. In conclusion, our findings support previous data that variability in the CIITA gene affects MS risk, but also that the effect is modulated by MS-associated HLA haplotypes. These findings further underscore the biological importance of HLA for MS risk.Genes and Immunity advance online publication, 16 January 2014; doi:10.1038/gene.2013.71.
|
|
