Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007570 (celiac disease)
 13,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The low serum transglutaminase found in various intestinal disorders (celiac disease and IBD) suggested to us to study the serum and mucosal transglutaminase behaviour in an experimental model of small intestine resection in rats to reduce cellular mass and induce enterocyte hyperproliferation in the proximal part left in continuity. Transglutaminase activity in the intestinal mucosa was significantly higher in resected rats than in control and sham operated animals from days 4 (121 +/- 10 v basal 94 +/- 3 mU/g protein, p < 0.01) to 10 (165 +/- 37 mU/g protein, p < 0.05) after surgery; no significant difference was observed at days 12 and 15 (110 +/- 15 and 105 +/- 23 respectively). Both serum alkaline phosphatase activity (partly produced in enterocytes) and serum transglutaminase were significantly lower in resected rats at each time-point beginning at day 6 (208 +/- 34 v 557 +/- 125 UI and 1.55 +/- 0.11 v 3.78 +/- 0.70 mU/ml, p < 0.001 respectively). These data suggest an involvement of transglutaminase in enterocyte proliferation and confirm the association between reduced intestinal mass and low levels of the enzyme in serum.
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PMID:Transglutaminase changes in intestinal mucosa after experimental small bowel resection in the rat. 136 17

By use of a radiometric assay transglutaminase activity was demonstrated for the first time in human jejunal mucosa. The activity is similar to that in other tissues, with a pH optimum of 9.0, an absolute requirement for Ca2+ and an apparent Km for putrescine of 0.15 mmol/l. Assay of jejunal transglutaminase activity with a variety of dietary proteins as acceptors showed high activity with gliadin, comparable with that of the standard substrate, dimethylcasein. Deamidation of the gliadin markedly reduced its acceptor activity. Collagen, ovalbumin, elastin and zein exhibited very low acceptor activities. Increased transglutaminase activity was demonstrated in jejunal biopsies from four patients with untreated coeliac disease compared with 14 control subjects and eight patients with inflammatory bowel disease. Eight patients with coeliac disease in remission, with normal levels of brush border alpha-glucosidase, showed elevated transglutaminase activities compared with those of controls. It is postulated that intestinal transglutaminase activity may be important in gliadin binding to tissues and thus in the pathogenesis of coeliac disease.
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PMID:Human jejunal transglutaminase: demonstration of activity, enzyme kinetics and substrate specificity with special relation to gliadin and coeliac disease. 285 82

The distribution of intestinal transglutaminase was investigated by immunofluorescence microscopy using rabbit anti-guinea pig transglutaminase immunoglobulin. Transglutaminase-related antigen was demonstrated principally in the cytoplasm of villous core interstitial cells with some activity in the brush border region of the villous epithelial cells. Implications for the pathogenesis of coeliac disease are discussed.
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PMID:Immunofluorescent localization of transglutaminase in rat small intestine. 289 85

A recent report indicates a relationship between human transglutaminase (TG) jejunal mucosa activity and celiac disease. We investigated the enzyme distribution along six consecutive small bowel segments of mucosa and tested TG activity on brush border membranes obtained from whole mucosa homogenate in Wistar rats. TG activity was significantly present in jejunal mucosa even if mostly detected in the distal part of small intestine. Our study indicates highest enzymatic activity in the subcellular fraction containing organelles and cellular membranes (66.8%) while a 7% activity was associated with the brush border fraction.
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PMID:Transglutaminase activity along the rat small bowel and cellular location. 289 25

Wheat, oat, rye and barley flours are toxic for celiac patients. Prevalence and incidence of Celiac Disease (CD), quite variable from country to country, are very high in Austria (1 out of 476 born alive) and low in France (1 out of 41.667 born alive). This difference is probably due to its multifactorial genesis. In a multicentric Italian study, histocompatibility antigens of HLA complex II were typed in 460 CD children. DR3 was present in 63% of the cases (Relative Risk = RR: 6.8), DR7 in 67% (RR: 3.8) and DR3/DR7 in 22.5% (RR: 10.5), while in 7.7 of patients both antigens were absent. Therefore in a certain percentage of CD patients these risk antigens are absent, while in the normal population they can be present. The probability of CD increases when HLA DR3 and DR7 are present (but their absence cannot exclude the disease. The main etiological factor is gluten and its fractions (B, B1, B2, fraction 9 etc.). It seems that breast feeding can prevent or delay the onset of CD, while the age at gluten introduction does not modify the risk. Pathogenetic mechanisms are still under discussion: 3 theories are under investigation. 1) Enzymatic theory: a proteolytic enzyme for gluten digestion could be lacking. This theory is not yet proven, while Bruce et al. found in the jejunal mucosa of CD patients an elevation of a transglutaminase, which binds the gluten to enterocytes. Its level does not seem to vary with the diet. 2) Lectinic theory: the gluten bind the enterocyte membrane by a lectinic mechanism and damage it.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Up-date on the etiopathogenesis of celiac disease]. 328 51

We have prospectively searched for IgA anti-transglutaminase antibodies by an enzyme-linked immunosorbent assay test in 20 untreated coeliacs and 21 patients with small bowel diseases other than coeliac disease consecutively referred to our Malabsorption Clinic. All the untreated coeliacs and one out of 21 disease controls turned out to be positive for the presence of these antibodies. The use of the enzyme-linked immunosorbent assay test for anti-transglutaminase antibodies could represent a new screening test for coeliac disease, in fact, this new enzyme-linked immunosorbent assay test has an absolute sensitivity and a satisfactory specificity and, in comparison to antiendomysial antibodies, is less expensive and avoids the ethical problems related to the use of monkey oesophagus.
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PMID:Tissue transglutaminase antibodies for coeliac disease screening. 983 5

In this paper we consider recent new data on the pathological features of gluten sensitivity and on the disease-associated antigens, in the context of a multistage hypothesis that we have been developing for the last five years. This incorporates concepts of oral tolerance induction, mucosal T-cell and antibody-mediated injury, and genetic contributions. Until now, there has been complete agreement that the diagnosis of celiac disease must be based on small bowel histology. There are patients with low-grade gluten-sensitive enteropathy, in whom the only morphological abnormality is a high count of intraepithelial lymphocytes (IEL). Some, but not all, also have positive serum IgA anti-endomysium antibody (AEA). With good techniques, in a properly accredited laboratory, in a patient suspected on clinical grounds to have celiac disease, a positive serum IgA AEA test (perhaps, alternatively, high-titer anti-transglutaminase by ELISA), is virtually diagnostic of the condition. Our hypothesis of a stepwise pathogenesis of severe gluten-sensitive enteropathy is re-examined in the light of these new data. It is evident that there are at least five different levels at which genetic influences may operate.
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PMID:Heterogeneity of celiac disease: clinical, pathological, immunological, and genetic. 992 74

Tissue transglutaminase C has recently been identified as one of the auto-antigens of endomysial antibodies found in coeliac disease. In this study we have cloned the human autoantigen and developed immunoassays measuring antibodies to transglutaminase in order to compare their diagnostic performance to that of established markers of the disease. A radiobinding assay using in vitro transcribed and translated 35S-methionine-labelled transglutaminase detected IgG antibodies in 110 and IgA antibodies in 109 of 112 patients at diagnosis of coeliac disease and in three and four of 92 control subjects, respectively. A radiobinding assay measuring both IgG and IgA transglutaminase antibodies identified 111 (99.1%) of the patients and 4 (4.3%) control subjects. Concordance of this assay with the IgA endomysial antibody test was found in 108 patients and 89 control subjects: two patients who had IgA deficiency and a third patient without IgA deficiency were only detected in the radiobinding assay; one patient had weak IgA endomysial antibodies only, and three of the control subjects with weak transglutaminase antibodies by radiobinding assay were undetectable in the IgA endomysial antibody assay. IgA and IgG ELISA using guinea pig transglutaminase and commercial ELISA measuring anti-gliadin antibodies had lower sensitivity and specificity than the radiobinding assays or the IgA endomysial antibody assay. This study confirms tissue transglutaminase C as a major autoantigen in coeliac disease and describes novel radiobinding assays for large scale testing to identify cases of coeliac disease.
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PMID:Comparison of tissue transglutaminase-specific antibody assays with established antibody measurements for coeliac disease. 1002 22

Type 1 diabetes and celiac disease are both immunologic disorders where specific HLA alleles are associated with disease risk. We have developed a radioassay for autoantibodies to tissue transglutaminase (tTG) following the report that this enzyme is 'the' endomysial autoantigen (EMA) of celiac disease. The radioassay for transglutaminase autoantibodies is similar to that utilized for detecting anti-islet autoantibodies. The 'cut-off' for the IgA autoantibody assay was established as 3 x 100th percentile of 184 healthy control subjects at an index of 0.05. Ninety-eight of 847 patients with type 1 diabetes (11.6%) had tissue transglutaminase autoantibodies (tTG). All EMA-positive patients were positive (49/49) for transglutaminase autoantibodies, as were 49/540 EMA-negative patients. Twenty transglutaminase-positive patients consented to intestinal biopsy and 15 biopsies were positive for celiac disease. All patients with a transglutaminase level greater than 0.70 (13/13) had a positive biopsy, while none (0/3) with a level <0.3 had a positive biopsy. The prevalence of transglutaminase autoantibodies was higher in diabetic patients with HLA DQ2 or DQ8. One third of DQ2 homozygous patients (22/68) expressed transglutaminase autoantibodies vs. less than 2% of patients lacking DQ2 or DQ8. A simple radioassay for IgA transglutaminase autoantibodies detects all endomysial antibody positive patients and detects transglutaminase autoantibodies in 5% of endomysial autoantibody negative patients. The prevalence of transglutaminase autoantibodies is associated with DQ2 and DQ8 and in particular DQ2 homozygosity. Autoimmunity to transglutaminase is remarkably prevalent amongst patients with type 1 diabetes expressing certain class II HLA alleles.
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PMID:One third of HLA DQ2 homozygous patients with type 1 diabetes express celiac disease-associated transglutaminase autoantibodies. 1044 Nov 79

We describe a novel high-throughput radiobinding assay for IgA antibodies to tissue transglutaminase (TG) which uses second antibody precipitation to isolate immune complexes. Using this assay, 24 of 25 patients with untreated coeliac disease (96%) and nine of 526 healthy blood donors (2%) had TG antibody levels above a threshold defined by the 97.5th centile of 347 schoolchildren. All patients and five of the nine blood donors with transglutaminase antibodies above this threshold were endomysial antibody (EMA) positive. Using this threshold, 410/445 (92%) routine clinical samples were concordant for TG antibodies and EMA, including 72 of 75 with EMA. TG antibodies above the 97.5th centile were found in 32 of 370 EMA negative samples, 15 of whom had anti-gliadin antibodies (AGA), histologically proven coeliac disease or partial villous atrophy. We conclude that this assay achieves a sensitivity and a specificity at least equivalent to those of EMA. It is technically simple and suitable for coeliac disease screening.
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PMID:Evaluation of a high-throughput second antibody radiobinding assay for measuring IgA antibodies to human tissue transglutaminase. 1055 45


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