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Query: UMLS:C0011854 (
type 1 diabetes
)
20,749
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Human epidemiological studies delineated early exposure to intact dietary protein (e.g., most infant formulas) as an environmental risk factor for the development of
IDDM
. The Trial to Reduce
IDDM
in the Genetically at Risk (TRIGR), an international
IDDM
prevention trial, has been designed to determine if avoidance of intact dairy protein in high-risk infants < or =6 months of age can reduce the subsequent diabetes incidence. We here studied the casein hydrolysate-based trial diet (Nutramigen) in NOD mice. When given either continuously or for 10 weeks after weaning, the test diet was highly effective in preventing autoimmune diabetes (32-week incidence: 4.6 vs. 58.8%) and in preserving pancreatic insulin levels, with little effect on islet inflammation. Spleen cells from protected NOD mice failed to adoptively transfer diabetes into irradiated syngeneic recipients. When co-transferred with splenocytes from diabetic donors, cells from diet-protected mice inhibited adoptive diabetes transfer (incidence 50 vs. 94%, P < 0.001). T-cell reactivity to the islet cell autoantigens ICA69 (islet cell antigen 69) and
GAD65
developed only in diabetic recipients of spleen cell grafts, indicating that diabetes protection extends to more than one autoantigen. In protected mice, ICA69 T-cell reactivity was not detectable spontaneously nor after priming with this autoantigen; however, priming with the cross-reactive non-self-antigen bovine serum albumin recruited T-cells responsive to ICA69. Thus, diabetes prevention with the clinical trial diet is effective in NOD mice, where it affects some T-cell repertoires and allows development of regulatory cells that interfere with destructive autoimmunity.
...
PMID:Immunological aspects of nutritional diabetes prevention in NOD mice: a pilot study for the cow's milk-based IDDM prevention trial. 907 94
Cytoplasmic islet cell antibodies (ICAs) are the classical serological markers for diagnosis and prediction of
IDDM
, but high technical demands have limited the widespread use of the histochemical ICA test. To investigate whether combined analysis of autoantibodies to two defined islet antigens can replace the histochemical ICA test, we established quantitative radioimmunoassays for autoantibodies to glutamate decarboxylase (
GAD65
-A), the tyrosine phosphatase IA2/ICA512 (IA2-A), and the cytoplasmic part of IA2 (IA2c-A). The
GAD65
-A and IA2c-A profiles of 920 sera from healthy individuals and from patients with
IDDM
, other organ-specific autoimmune diseases, and polyendocrine autoimmune syndrome were compared with the ICA profiles from these same individuals. Combined analysis of
GAD65
-A and IA2c-A detected 93-100% of the ICA+ sera, and, at equal specificity, improved the diagnostic sensitivity (85%) for
IDDM
compared with that of ICA (74%). This effect was especially pronounced in children with disease onset before 16 years of age (91% sensitivity). To replace ICA testing in risk assessment for
IDDM
, we designed a strategy adapted to study groups with low antibody prevalence. A combined radioimmunoassay for single-step detection of
GAD65
-A and IA2c-A was developed, and positive sera were reanalyzed to define their single autoantibody specificity. We identified 93% of the ICA+ sera from 204 first-degree relatives of
IDDM
patients. Single-step detection reduced costs and effort by more than 40% compared with separate testing, allowing an efficient large-scale screening of sera for
GAD65
-A and IA2c-A in
IDDM
. In sum,
GAD65
-A and IA2c-A detected much ICA reactivity, and their combined evaluation and detection is suitable to replace the histochemical ICA test.
...
PMID:Combined analysis and single-step detection of GAD65 and IA2 autoantibodies in IDDM can replace the histochemical islet cell antibody test. 907 95
Migration of lymphocytes to the pancreas is a prerequisite for insulitis in
IDDM
. Mucosal vascular addressin (MAdCAM-1), involved in the recirculation of lymphocytes to the gut, has been found in the inflamed islets in NOD mice. In humans, triggers of the gut immune system (e.g., early exposure to cow's milk proteins in infancy, exposure to enteroviral infections) have been associated with
IDDM
. To study the possible link between the gut immune system and
IDDM
, we tested the expression of the alpha4beta7-integrin, a homing receptor for MAdCAM-1, on
GAD65
-reactive lymphocytes. Using immunomagnetic cell sorting, we depleted the lymphocytes with high expression of alpha4beta7-integrin in the peripheral blood mononuclear cell population from
IDDM
patients and patients with autoimmune polyendocrine disease type 1 (APD-I). The depletion led to a marked decrease (mean 70%) in the cellular response against
GAD65
in three of six
IDDM
patients and in one subject at high risk for
IDDM
. A decrease of 37% in the GAD response was observed after depletion in the case of one APD-I patient who also had
IDDM
. Cellular response to tetanus toxoid increased in the majority of patients as well as in three control subjects studied. We demonstrated that a remarkable population of islet cell antigen-reactive lymphocytes express the gut-specific homing receptor, which emphasizes the role of gut immunity in
IDDM
. The manipulation of the gut immune system is therefore proposed as a tool for modulation of the autoimmunity against pancreatic beta-cells in
IDDM
.
...
PMID:Glutamate decarboxylase-reactive peripheral blood lymphocytes from patients with IDDM express gut-specific homing receptor alpha4beta7-integrin. 907 97
We have utilized the NOD islet beta-cell line NIT-1 to monitor beta-cell specific autoantibodies and to investigate the modulation of
IDDM
in NOD mice by NIT-1 membrane associated antigens. The sera from diabetic but not from pre-diabetic or protected NOD mice strongly stained NIT-1 cells in FACS analysis. The cell surface antigens on NIT-1 cells were trypsin-sensitive. NIT-1 cells could not be stained by anti-mouse GAD67 antibody; however, we could demonstrate the presence of
GAD65
and GAD67 mRNA by RT-PCR. Longitudinal analysis of anti-NIT-1 antibodies showed that these antibodies were present in the neonates but disappeared after weaning. Sonicated NIT-1 cell membrane preparations protected NOD mice from diabetes when injected intravenously in 5 week old mice. The protection was associated with reduced cytotoxic activity and elevated Th2-like responses as indicated by IgG1 antibodies against the NIT-1 cells. Subcutaneous injection of sonicated NIT-1 membranes or the injection of control red blood cell membranes failed to induce protection. We conclude that NIT-1 cell membranes do not express GAD but contain other antigens that are important in the development and prevention of
IDDM
. These antigens could be useful for the diagnosis of diabetes by monitoring autoantibody levels and for the modulation of
IDDM
by immunotherapy.
...
PMID:Modulation and detection of IDDM by membrane associated antigens from the islet beta cell line NIT-1. 908 Feb 97
Autoantibodies to 65 kD glutamic acid decarboxylase (GADAA) and ICA512 (ICA512AA) were measured by radioimmunoassays using as antigens in vitro transcribed and translated [35S]-methionine-labeled human
GAD65
and ICA512 (IA-2). The prevalence of GADAA and ICA512AA in sera from 87 patients with
IDDM
was 39 and 23%, respectively. The frequency and titer of ICA512AA declined sharply within 5 years after the onset of
IDDM
. Among patients tested within 4 years after diagnosis, the prevalence of ICA512AA was significantly higher in acute onset
IDDM
than in slowly progressive
IDDM
(37 versus 6%, P < 0.025) irrespective of age, while there was no difference in GADAA frequency between acute onset and slowly progressive subtypes (51 versus 63%). A total of two patients out of 121 patients with NIDDM were positive for GADAA, and two other NIDDM patients, who were suffering from sarcoidosis, were positive for ICA512AA. Neither of the antibodies were positive in sera from four atypical NIDDM patients, aged < 20 years, who showed ketosis at onset and required insulin followed by excellent metabolic control with diet restriction alone. These observations suggest that ICA512AA are associated with rapid progression of beta cell damage in
IDDM
. ICA512 radioassay, in combination with GAD assay may provide a useful diagnostic marker for
IDDM
especially in youth.
...
PMID:Combined measurements of GAD65 and ICA512 antibodies in acute onset and slowly progressive IDDM. 917 63
Islet antigens associated with
type 1 diabetes
include a recently identified protein tyrosine phosphatase-like molecule IA-2, which contains the intracellular fragment IA-2ic. To determine whether combinations of antibodies including those to IA-2 characterize and predict
type 1 diabetes
, we studied antibodies to IA-2, IA-2ic, glutamic acid decarboxylase (
GAD65
), and islet cell antibodies (ICAs) in 1) 60 newly diagnosed type 1 diabetic patients followed for 1 year, 2) 31 monozygotic twin pairs discordant for
type 1 diabetes
followed up to 12 years (11 twins developed diabetes), 3) 18 dizygotic twin pairs discordant for
type 1 diabetes
, and 4) normal healthy control subjects. Newly diagnosed type 1 diabetic patients frequently had antibodies to IA-2 (62%), IA-2ic (67%),
GAD65
(77%), and ICAs (85%). The intracellular fragment of IA-2 probably contains the immunodominant epitope as 137 of 143 samples with IA-2 antibodies from type 1 diabetic patients also had IA-2ic antibodies. Monozygotic twins were usually discordant for antibody specificities. Concordance was higher in monozygotic than matched dizygotic twins for both antibody combinations (33 vs. 6%, P < 0.05) and the development of diabetes (33 vs. 0%, P < 0.01). In monozygotic twins, all the antibodies were highly predictive of
type 1 diabetes
(positive predictive values all >87%), although antibodies were also detected in twins at low risk of disease. In summary, IA-2 emerges as a major antigen associated with
type 1 diabetes
and distinct from
GAD65
. Type 1 diabetes-associated autoimmunity, which is probably induced by environmental factors, does not necessarily herald progression to the disease. However, genetic factors may influence the development of combinations of disease-associated antibodies and the progression to
type 1 diabetes
.
...
PMID:Value of antibodies to islet protein tyrosine phosphatase-like molecule in predicting type 1 diabetes. 923 50
Marked differences have been reported in the prevalence of glutamic acid decarboxylase (GAD) antibodies between Caucasian (63-84%) and Japanese (30-50%) or Asian (5-50%)
IDDM
patients. Using a new immunoprecipitation assay based on 125I-labelled recombinant human
GAD65
we have reassessed prevalence of
GAD65
antibodies in Japanese patients. We also assessed prevalence of IA-2 antibodies.
GAD65
antibodies were detected in 83.3% of sera taken within 1 year of onset, comparable to the prevalence reported in Caucasian patients. Positivity decreased to 66.7% after 2 to 3 years and to 54.3% after 3 years from onset, still higher than previously reported Asian prevalence. Except in one patient, high antibody levels persisted chronically, up to 12 years. There was no difference in the prevalence of
GAD65
antibodies between Japanese
IDDM
patients with and without autoimmune thyroid disease (AITD). IA-2 antibodies were detected in 64.7% of sera taken within 1 year of onset. Prevalence of IA-2 antibodies was lower than that of
GAD65
antibodies. The difference in positivity in Asian
IDDM
patients between present and previous reports arose from the sensitivity of our assay for
GAD65
antibodies. Additionally, the patients we studied had classic
IDDM
with a well-defined onset. We conclude that prevalence of
GAD65
antibodies in Japanese
IDDM
patients is comparable to that in Western studies. There was no relationship of
GAD65
antibody positivity to coexistence of AITD. Our results suggest that autoimmunity is the most significant cause of Japanese
IDDM
.
...
PMID:High prevalence of GAD65 (and IA-2) antibodies in Japanese IDDM patients by a new immunoprecipitation assay based on recombinant human GAD65. 930 Feb 29
Islet cell antigen p69 (ICA69) is a target autoantigen in
IDDM
. Studies of T-cells from newly diabetic children suggested possible antigenic mimicry between human ICA69 (in particular the Tep69 T-cell epitope, aa 36-47) and the ABBOS region in bovine serum albumin (BSA; aa 152-169), one of several cow's milk proteins that evoke abnormal immunity in diabetes-prone hosts. We recently found the sequence of Tep69 regions to be identical in the four alternatively spliced human and rodent ICA69 isoforms. Immunization of nonobese diabetic (NOD) mice with BSA or ICA69 generates fully cross-reactive T-cell responses to both Tep69 and ABBOS as the immunodominant, naturally generated, and presented T-cell mimicry epitopes. Such responses are absent or weak in healthy strains of mice. NOD mouse recipients of adoptive spleen cell grafts from diabetic donors spontaneously generate easily detectable pools of T-cells specific for ICA69/BSA, as well as the unrelated
GAD65
. NOD mice injected neonatally with ABBOS or Tep69 show cross-tolerance, but ABBOS-induced tolerance is transient. Neonatal injection of Tep69 reduces disease incidence (23 vs. 68%
IDDM
, P < 0.02), while neonatal injection of ABBOS has little effect. In contrast, systemic immunization of young NOD females with ABBOS (but not Tep69) reduces the diabetes incidence and delays disease expression, with protected mice generating ABBOS-specific T-cell repertoires unable to recognize the Tep69 mimicry antigen. Our observations demonstrate a loss of self-tolerance to ICA69 in NOD mice, and they establish antigenic mimicry between the two T-cell epitopes in ICA69 and BSA. Further studies are necessary to understand the molecular basis of this mimicry and how either T-cell peptide can modify the disease course.
...
PMID:Loss of self-tolerance to ICA69 in nonobese diabetic mice. 931 48
Antibodies to the 40 kD antigen (identified as tyrosine phosphatase IA-2) and glutamate decarboxylase (
GAD65
) are strongly associated with
insulin dependent diabetes mellitus
(
IDDM
). However, antibodies to GAD (GADA) can appear in the absence of
IDDM
, particularly in stiff man syndrome (SMS) and in some individuals with autoimmune polyendocrine syndrome type II (APS II) and organ specific autoimmune diseases. The aim of this study was to compare the specificity of IA-2 antibodies (IA-2A) and GADA for
IDDM
by determining their frequency in different patient groups. IA-2A were present in 64/114 (56%)
IDDM
patients and 9/19 (47%) APS II patients with
IDDM
but in only 4/28 (14%) SMS patients. 1/24 (4%) APS II patients without
IDDM
and 1/113 (0.9%) patients with organ specific autoimmune disease had low level IA-2A. In contrast GADA were present in 77/114 (68%)
IDDM
patients and 17/19 (89%) APS II patients with
IDDM
, but also in 25/28 (89%) SMS patients, 5/24 (21%) APS II patients without
IDDM
and 22/113 (19%) patients with organ specific autoimmune diseases. Furthermore, within the group of new onset
IDDM
, IA-2A seemed to be associated with ICA and age: 63% of ICA positive
IDDM
patients had IA-2A (74% had GADA) increasing to 77% in the group below 20 years of age (69% for GADA). Our results demonstrate that IA-2A may be more specific for
IDDM
than GADA, as the latter are also present in patients with SMS, APS II without
IDDM
and organ specific autoimmune diseases. IA-2A were less frequent in older patients with
IDDM
than GADA or ICA. A combination of IA-2A and GADA detected 84% of total and 93% of ICA positive
IDDM
patients.
...
PMID:Antibodies to the tyrosine phosphatase-like protein IA-2 are highly associated with IDDM, but not with autoimmune endocrine diseases or stiff man syndrome. 934 28
Apart from genes in the HLA complex (
IDDM1
) and the variable number of tandem repeats in the 5' region of the insulin gene (INS VNTR, IDDM2), several other loci have been proposed to contribute to
IDDM
susceptibility. Recently, linkage and association have been shown between the cytotoxic T lymphocyte-associated protein 4 (CTLA-4) gene on chromosome 2q and
IDDM
. In a registry-based group of 525 recent-onset
IDDM
patients <40 years old we investigated the possible interactions of a CTLA-4 gene A-to-G transition polymorphism with age at clinical disease onset and with the presence or absence of established genetic (HLA-DQ, INS VNTR) and immune disease markers (autoantibodies against islet cell cytoplasm (ICA); insulin (IAA); glutamate decarboxylase (
GAD65
-Ab); IA-2 protein tyrosine phosphatase (IA-2-Ab)) determined within the first week of insulin treatment. In new-onset
IDDM
patients. G-allele-containing CTLA-4 genotypes (relative risk (RR)= 1.5; 95% confidence interval (CI) = 1.2-2.0; P < 0.005) were not preferentially associated with age at clinical presentation or with the presence of other genetic (HLA-DR3 or DR4 alleles; HLA-DQA1*0301-DQB1*0302 and/or DQA1*0501-DQB1*0201 risk haplotypes; INS VNTR I/I risk genotype) or immune (ICA, IAA, IA-2-Ab,
GAD65
-Ab) markers of diabetes. For 151 patients, thyrogastric autoantibodies (anti-thyroid peroxidase, anti-thyroid-stimulating hormone (TSH) receptor, anti-parietal cell, anti-intrinsic factor) were determined, but association between CTLA-4 risk genotypes and markers of polyendocrine autoimmunity could not be demonstrated before or after stratification for HLA- or INS-linked risk. In conclusion, the presence of a G-containing CTLA-4 genotype confers a moderate but significant RR for
IDDM
that is independent of age and genetic or immune disease markers.
...
PMID:CTLA-4 gene polymorphism confers susceptibility to insulin-dependent diabetes mellitus (IDDM) independently from age and from other genetic or immune disease markers. The Belgian Diabetes Registry. 935 55
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