| 1. |
- Sanjeevi, Carani B., et al.
(författare)
-
The risk conferred by HLA-DR and DQ for type 1 diabetes in 0-35-year age group are different in different regions of Sweden
- 2008
-
Ingår i: Annals of the New York Academy of Sciences. - : Wiley. - 0077-8923 .- 1749-6632. - 9781573317337 ; 1150, s. 106-11
-
Tidskriftsartikel (refereegranskat)abstract
- HLA DR4-DQ8 and DR3-DQ2 haplotypes account for 89% of newly diagnosed cases of type 1 diabetes (T1D) in Sweden. The presence of a single copy of DQ6 confers protection. The aim of the present study is to evaluate whether the risk conferred by high risk HLA DR and DQ to T1D is similar in all regions of Sweden and see whether there are any significant regional differences. The subjects comprised 799 consecutively diagnosed T1D patients and 585 age-, sex-, and geography-matched healthy controls in the age group 0-35 years. HLA typing for high-risk haplotypes was previously performed using PCR-SSOP and RFLP. The results showed that HLA DR3-DR4 gave an odds ratio of 8.14 for the whole of Sweden. However, when the study group was divided into six geographical regions, subjects from Stockholm had the highest OR, followed by those from Lund, Linköping, Gothenburg, Umeå, and Uppsala. Absolute protection was conferred by the presence of DQ6 in subjects from the Linköping region, but varied in the other regions. The frequency of DR3 and DQ2, DR4 and DQ8, DR15, and DQ6 in patients showed high linkage for each region, but were different between regions. In conclusion: The risk conferred by high-risk HLA varies in different regions for a homogenous population in Sweden. The results highlight the important role played by the various environmental factors in the precipitation of T1D.
|
|
| 2. |
- 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.
|
|
| 3. |
- 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.
|
|
| 4. |
|
|
| 5. |
- Hagopian, William A., et al.
(författare)
-
Glutamate decarboxylase-, insulin-, and islet cell-antibodies and HLA typing to detect diabetes in a general population-based study of Swedish children
- 1995
-
Ingår i: Journal of Clinical Investigation. - 0021-9738. ; 95:4, s. 1505-1511
-
Tidskriftsartikel (refereegranskat)abstract
- Most autoimmune diabetes occurs in those without a diabetic relative, but few cases are identifiable prospectively. To model general population prediction, 491 consecutive newly diabetic children from all of Sweden were tested for autoantibodies to glutamate decarboxylase (GAD65ab), insulin (IAA), and islet cells (ICA), and for HLA-DQ genotypes by PCR; 415 matched control children were tested in parallel. GAD65ab sensitivity/specificity was 70/96%, versus 84/96% for ICA, 56/97% for IAA, 93/93% (any positive), 39/99.7% (all positive), and 41/99.7% (GAD65ab plus IAA). The latter's 25% predictive value was not improved by requiring concomitant high-risk HLA genotypes. GAD65ab were associated with DQA1*0501/B1*0201 (DQ2; P = 0.007) but not DQA1*0301/B1*0302 (DQ8), and IAA with DQA1*0301/B1*0302 (DQ8; P = 0.03) but not DQA1*0501/B1*0201 (DQ2). GAD65ab were more prevalent in females than males (79 vs. 63%; P < 0.0001) but did not vary with onset age nor season. Combining the three antibody assays yielded sufficient sensitivity for screening. GADab were relatively sensitive/specific for diabetes, but even with HLA marker combinations yielded predictive values insufficient for early immunointervention in the low-prevalence general population.
|
|
| 6. |
- Ivarsson, Sten-A., et al.
(författare)
-
Glutamate decarboxylase antibodies in non-diabetic pregnancy precedes insulin-dependent diabetes in the mother but not necessarily in the offspring
- 1997
-
Ingår i: Autoimmunity. - 0891-6934. ; 26:4, s. 261-269
-
Tidskriftsartikel (refereegranskat)abstract
- We studied the risk for diabetes of glutamate decarboxylase (GAD65Ab) and islet cell (ICA) autoantibodies in non-diabetic pregnant mothers and their children. Pregnancy and cord blood sera were collected in 1970-87 from about 35,000 mothers who delivered a child in the city of Malmo, Sweden. A total of 42 mothers were identified in 1988 who, 1-18 years after their pregnancies, had developed either insulin-dependent (n = 22) or non-insulin dependent (n = 20) diabetes mellitus. First, in 123 pregnant mothers selected as controls, 0.8% had GAD65Ab and 0.8% ICA. Second, among the mothers with non-insulin dependent diabetes, 7/20 (35%) had GAD65Ab eight months to 13 years, 10 months before clinical diagnosis. Third, in mothers who later developed insulin-dependent diabetes, 12/22 (55%) had GAD65Ab and 10/22 (45%) had ICA in pregnancies preceding the clinical diagnosis by 13 months to 9 years, 4 months. In 1996, none of the children born to the 42 mothers have developed diabetes. GAD65Ab and ICA in non-diabetic pregnancies may predict insulin-dependent diabetes in the mother but not necessarily in the offspring.
|
|
| 7. |
- 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.
|
|
| 8. |
- Kockum, Ingrid, et al.
(författare)
-
Genetic and immunological findings in patients with newly diagnosed insulin-dependent diabetes mellitus
- 1996
-
Ingår i: Hormone and Metabolic Research. - : Georg Thieme Verlag KG. - 0018-5043 .- 1439-4286. ; 28:7, s. 344-347
-
Tidskriftsartikel (refereegranskat)abstract
- Two large population-based case-control studies are reviewed. The aim is to determine the effects of HLA, other genetic factors and immune markers (ICA, IAA and GAD65Ab) on the age at onset of insulin-dependent diabetes mellitus (IDDM) in 0-34 year olds. The primary HLA risk gene sequence for IDDM was difficult to identify because of the low recombination frequency within the HLA region. The frequency of the DR3-DQA1 * 0501-DQB1 * 0201 haplotype and the DR3-DQA1 * 0501 DQB1 * 0201 (DQ2)/DR4-DQA1 * 0301-DQB1 * 0302 (DQ8) genotype were higher among patients diagnosed before the age of 10 compared with those diagnosed after the age of 30. The negatively associated haplotype, DR15-DQA1 * 0102-DQB1 * 0602 was absent before the age of 10, but the frequency increased with increasing age at onset. The IDDM2 gene representing the variable number of tandem repeat (VNTR) sequences and 5' of the insulin gene on chromosome 11 were associated with IDDM since homozygous short VNTR was positive but not homozygous, and heterozygous long VNTR was negatively associated with the disease. The diagnostic sensitivity and specificity of GAD65 (GA65Ab) and insulin (IAA) autoantibodies varied with the age at onset and gender. GAD65Ab had the highest sensitivity (> 80%) in patients older than 20 years of age with no difference in gender. The lowest sensitivity (54%) was in 0-10 year old boys, while age did not affect the sensitivity in girls. In contrast, the sensitivity of IAA was highest (46%) before the age of 15 but decreased thereafter as did the sensitivity for ICA. Classification of patients who develop IDDM above 20-25 years of age was inadequate since many patients classified with NIDDM either had GAD65Ab or ICA or developed these antibodies after 1-2 years of NIDDM. We conclude that not only age but also gender affects the risk for IDDM associated with HLA, other IDDM genes as well as commonly used immunological markers for IDDM.
|
|
| 9. |
- Lindberg, Bengt, et al.
(författare)
-
Prevalence of β-cell and Thyroid Autoantibody Positivity in Schoolchildren during Three-Year Follow-up
- 1999
-
Ingår i: Autoimmunity. - : Informa UK Limited. - 0891-6934 .- 1607-842X. ; 31:3, s. 175-185
-
Tidskriftsartikel (refereegranskat)abstract
- The prevalence of autoantibodies against the 65 kD isoform of glutamic acid decarboxylase (GAD65Ab), insulin (IAA), islet cells (ICA), thyroid peroxidase (TPOAb) and thyroglob-ulin (TgAb), in relation to HLA-DR types, was assessed in 310 (HLA in 280) twelve-year-old children during three-year follow-up. Altogether, 26.8% (83?10) of the children were found to carry at least one autoantibody. The HLA-DR3/DR4 genotype was significantly more prevalent in the subgroup of children GAD65Ab-positive on at least one occasion than among GAD65Ab-negative children |33% (2/6) vs. 5% (12/274);? = 0.03|, as was the HLA-DR4/x genotype among children seropositive for at least one thyroid autoantibody, compared to the corresponding seronegative subgroup [52% (34/65) vs. 34% (74/215); p = 0.01]. The proportion of children seropositive in at least one of the three tests was 1.9% (6?10) for GAD65Ab, 2.6% (8?10) for IAA, 5.2% (16?10) for ICA, 11.3% (35?10) for TPOAb and 19.4% (60?10) for TgAb. All autoantibodies except GAD65Ab tended to disappear during follow-up, and at the three-year follow-up IAA had disappeared in 50% (2/4) of cases, ICA in 67% (6/9), TPOAb in 30% (6/20) and TgAb in 38% (18/47) of cases. The turnover of seropositive subjects and the large proportion of children seropositive for at least one islet or thyroid autoantibody during a three-year follow-up suggest transient autoantibodies to be more common than is discernible in cross-sectional investigations
|
|
| 10. |
- Oak, Shilpa, et al.
(författare)
-
The lack of anti-idiotypic antibodies, not the presence of the corresponding autoantibodies to glutamate decarboxylase, defines type 1 diabetes
- 2008
-
Ingår i: Proceedings of the National Academy of Sciences. - : Proceedings of the National Academy of Sciences. - 1091-6490 .- 0027-8424. ; 105:14, s. 5471-5476
-
Tidskriftsartikel (refereegranskat)abstract
- Autoantibodies to glutamate decarboxylase 65 (GAD65Ab) are commonly believed to be a major characteristic for type 1 diabetes (T1D). We investigated the presence of GAD65Ab in healthy individuals (n = 238) and first-degree relatives (FDRs) of T1D patients (n = 27) who tested negative for GAD65Ab in conventional RIAs. Sera were applied to affinity columns coated with GAD65-specific mAbs to absorb anti-idiotypic antibodies (anti-Ids). The absorbed sera were analyzed for binding to GAD65 by RIAs. Both healthy individuals and FDRs present GAD65Ab that are inhibited by anti-Id, masking them in conventional detection methods. The presence of GAD65Ab-specific anti-Ids was confirmed by competitive ELISA. Remarkably, T1D patients (n = 54) and Stiff Person Syndrome patients (n = 8) show a specific lack of anti-Ids to disease-associated GAD65Ab epitopes. Purified anti-Ids from healthy individuals and FDRs inhibited the binding of GAD65Ab from T1D patients to GAD65. We conclude that masked GAD65Ab are present in the healthy population and that a lack of particular anti-Ids, rather than GAD65Ab per se, is a characteristic of T1D. The lack of these inhibitory antibodies may contribute to T cell activation by GAD65Ab.
|
|
