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)

Binding of 125I-crude gluten digest (Frazer's fraction III. FF-III) and 125I-concanavalin A (Con A) to isolated rat enterocytes and of 125I-FF-III to human enterocytes was investigated. Specific binding of 125I-FF-III to rat enterocytes was observed but binding was not inhibited by any of a range of simple and complex saccharides. although casein and bovine serum albumin displaced FF-III at high concentrations. Con A also bound to enterocytes in a specific manner and was inhibited by alpha-methyl-D-mannoside, confirming a lectin-mediated interaction. 125I-FF-III exhibited quantitatively similar specific binding to both normal human and coeliac enterocytes. The primary interaction of gliadin peptides with the enterocyte surface membrane is not lectin-mediated and unlikely to be of fundamental importance in the pathogenesis of coeliac disease.
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PMID:Gliadin binding to rat and human enterocytes. 358 85

The agglutinating properties of a crude gluten digest, purified gliadin fractions and established plant lectins were investigated using mammalian erythrocytes, rat enterocytes and normal and coeliac human enterocytes as the target systems. Gliadin preparations failed to cause agglutination of any of the cells tested, whereas established pure plant lectins were active cell agglutinins. These studies indicate that gliadin peptides do not interact with intestinal cells in a polyvalent, lectin-like manner and as such cannot be regarded as true lectins. Mucosal damage in coeliac disease is unlikely therefore to be related to lectin-like activity of gliadin.
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PMID:Reappraisal of the 'lectin hypothesis' in the aetiopathogenesis of coeliac disease. 370 69

Serum IgG and IgA antibodies to wheat germ agglutinin (WGA) were measured by an enzyme-linked immunosorbent assay (ELISA) with N-acetyl-D-glucosamine in all incubation steps to inhibit sugar-specific binding. Patients with coeliac disease (CD) had significantly higher antibody levels to WGA than patients with other intestinal disorders or healthy controls. Similar results were obtained for antibodies to the gluten fraction glyc-gli. The WGA antibodies did apparently not cross-react with gluten antigens, but commercial gluten powder contained traces of WGA or a similar lectin. Our findings support the proposal that WGA may be involved in the pathogenesis of CD.
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PMID:Antibodies to wheat germ agglutinin in coeliac disease. 375 86

Dietary lectins of gluten origin have been suggested to play an important role in the mechanisms leading to the characteristic morphology of the intestine found in patients with celiac disease. To further explore this issue we have used Wheat Germ Agglutinin (WGA) or Concanavalin A (Con A) to challenge rat small intestine and study the ultrastructural changes of such a treatment. Both lectins affected the enterocytes at the base of the villi more than those at the top. The morphological findings included disarrangement of the cytoskeleton, increased endocytosis and shortening of the microvilli. The interrelationship between the observed changes, and their relevance for similar morphological alterations found in patients with celiac disease are discussed. In conclusion, the morphological findings in our rat model resemble early changes in patients with celiac disease, thus supporting the idea that lectins or lectin-like substances are involved in the pathogenesis of this disease.
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PMID:Morphological changes of rat small intestine after short-time exposure to concanavalin A or wheat germ agglutinin. 376 64

It has been speculated that gluten may play a role in the pathogenesis of dermatitis herpetiformis (DH) because it can act as a lectin. The lectin activity of gluten preparations was recently identified as wheat germ agglutinin (WGA). IgG and IgA serum antibodies to WGA and gluten were therefore measured in patients with DH and coeliac disease (CD) by an enzyme-linked immunosorbent assay (ELISA). Compared with healthy controls, both patients categories had increased IgG and IgA activities to WGA and gluten, the CD group showing the highest antibody levels. DH patients with subtotal villous atrophy tended to have higher activities than those with no villous changes or only minor changes. No significant difference in the gluten-to-WGA ratio of IgA or IgG antibodies was found when DH patients were compared with CD patients. If WGA plays a pathogenetic role in DH, then DH patients must have dermal characteristics, as yet undefined, that explain the initiation of their skin disease.
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PMID:Serum antibodies to wheat germ agglutinin and gluten in patients with dermatitis herpetiformis. 378 2

The gluten lectin was isolated by affinity chromatography, separated by sodium dodecyl sulphate-gel electrophoresis together with purified wheat germ agglutinin (WGA) and electrotransferred to nitrocellulose filters. The binding pattern of anti-WGA to the blotted filters confirmed the presence of WGA in gluten. A lectin from rice bran and white rice flour, respectively, was isolated by affinity chromatography. Both lectins reacted with anti-WA in immunoblotting. As patients with coeliac disease are known to tolerate rice flour, the finding of a WGA-like lectin questioned the suggestion that WGA in gluten is involved in the pathogenesis of coeliac disease. A second lectin was also isolated from rice flour which reacted only with antibodies against soybean lectin on immunoblots. This may indicate a contamination of soybean proteins in rice flour.
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PMID:Immunoblotting detection of lectins in gluten and white rice flour. 382 97

A lectin in gluten was detected by agglutination of papain-treated human erythrocytes. A partially purified lectin preparation was obtained by chromatography on immobilized ovalbumin. This fraction showed the same sugar specificity as wheat germ agglutinin (WGA). There was no indication of lectins with carbohydrate specificities different from WGA in the various gluten fractions examined. Small amounts of the gluten lectin was then isolated by using an affinity column with specificity for WGA. Analyses of this gluten lectin by sodium dodecyl sulphate-gel electrophoresis showed bands with the same mobility as that of purified WGA. Our results indicate that the lectin properties of gluten are due to traces of WGA. This finding is relevant for theories about the pathogenesis of coeliac disease.
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PMID:Lectin activity of gluten identified as wheat germ agglutinin. 383 72

This paper is a critical appraisal of current theories on the mechanisms of toxicity of wheat and other cereals in celiac disease and some related enteropathies. The "peptidase deficiency," "primary immune defect," and "gluten-lectin" theories on celiac disease are examined and critically discussed on the basis of the relevant data available in 88 references. Special attention has been paid in this review to the nature of the cereal components triggering the appearance of toxic symptoms and signs in celiac disease as well as to underlying action mechanisms. The gluten-lectin theory is the one best able to explain, in addition to celiac disease, some secondary intolerances that may occur in temporarily predisposed individuals as a consequence of several causes, including viral hepatitis and intestinal infections, as well as the occurrence of intestinal lesions in healthy subjects administered very high amounts of gluten.
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PMID:Toxicity mechanisms of wheat and other cereals in celiac disease and related enteropathies. 390 76

Observations are reported by scanning electron microscopy (SEM) of soy protein-induced villous atrophy and mucosal recovery in two infants aged 5 weeks and 4 1/2 months. Whereas, by light microscopy, the mucosal lesions appeared similar, i.e., a flat mucosa, their appearance by SEM was different: the damage appeared more severe in the younger infant, although there was a shorter period of exposure to soy protein. The mucosal architecture was restudied 6 weeks after the initial biopsy. The degree of mucosal reconstruction was more advanced in the older infant--the one who showed less severe damage by SEM on the first biopsy. Although these investigations by SEM of damaged small bowel mucosa in soy protein intolerance did not contribute definite information to clarify the pathogenesis of villous atrophy in this condition, the injury was consistent with a lectin-induced toxicity, similar to the one postulated for celiac disease. SEM seems eminently suited to study of the effect of interactions between environment and host at mucosal surfaces; and finer gradations of damage to small bowel mucosa can be determined better by SEM, while this is not possible by light microscopy. Of interest was the rather extensive colonization of the mucosal surface by microorganisms in one of the two patients. However, the contribution of microbial colonization to mucosal damage could not be assessed.
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PMID:Scanning electron microscopy of soy protein-induced damage of small bowel mucosa in infants. 668 55

Although a variety of plant lectins are consumed as part of the normal human diet and are capable of binding to intestinal cell surfaces in vitro, little information exists on their effects on intact intestine. We have studied the acute effects of intraluminal administration of wheat germ agglutinin and concanavalin A in normal rats. Both lectins caused increased shedding of brush border membrane and, at higher concentrations, reduction in surface area, acceleration of cell loss, and shortening of villi. These changes were prevented by simultaneous administration of the appropriate sugar to inhibit binding, indicating that the effects were related to binding to carbohydrate residues of intestinal cells. Similar changes of brush borders were found after intraluminal administration of antiserum to sucrase-isomaltase, a surface protein of the brush border membrane, suggesting that the lectin effects resulted from cell surface receptor-lectin interaction rather than a primary intracellular effect. Our results suggest that dietary lectins may be in part responsible for normal turnover of brush border membrane, and support, in addition, the possibility that certain intestinal diseases such as celiac sprue may be the consequence of increased levels of lectin receptor allowing a dietary lectin to exert a toxic effect.
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PMID:In vivo responses of rat intestinal epithelium to intraluminal dietary lectins. 689 78


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