Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153470 (Spleen)
 4,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study was undertaken to evaluate tissue transglutaminase (TG2) expression in guinea pig tissues, using an antibody against the guinea pig liver TG2. The tests were performed by means of a few immunohistochemical methods in specimens from: gut, skin, the lungs, lymph nodes, the heart, the thymus, the spleen, skeletal muscles of control guinea pigs and from inflamed skeletal muscles and skin. TG2 expression was found in artery, vein and lymphatic vessel endothelia, in mesothelia of pleura, pericardium and peritoneum, and in smooth muscle cells. Spleen deserves a special attention, since this organ, especially rich in TG2, may be much more involved in celiac disease and in liver diseases than it has been accepted so far. The subject calls for further elucidation.
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PMID:Expression of tissue transglutaminase in blood and lymphatic vessel endothelia and in mesothelium. 1563 21

Celiac disease, triggered by wheat gliadin and related prolamins from barley and rye, is characterized by a strong association with HLA-DQ2 and HLA-DQ8 genes. Gliadin is a mixture of many proteins that makes difficult the identification of major immunodominant epitopes. To address this issue, we expressed in Escherichia coli a recombinant alpha-gliadin (r-alpha-gliadin) showing the most conserved sequence among the fraction of alpha-gliadins. HLA-DQ8 mice, on a gluten-free diet, were intragastrically immunized with a chymotryptic digest of r-alpha-gliadin along with cholera toxin as adjuvant. Spleen and mesenteric lymph node T cell responses were analyzed for in vitro proliferative assay using a panel of synthetic peptides encompassing the entire sequence of r-alpha-gliadin. Two immunodominant epitopes corresponding to peptide p13 (aa 120-139) and p23 (aa 220-239) were identified. The response was restricted to DQ and mediated by CD4+ T cells. In vitro tissue transglutaminase deamidation of both peptides did not increase the response; furthermore, tissue transglutaminase catalyzed extensive deamidation in vitro along the entire r-alpha-gliadin molecule, but failed to elicit new immunogenic determinants. Surprisingly, the analysis of the cytokine profile showed that both deamidated and native peptides induced preferentially IFN-gamma secretion, despite the use of cholera toxin, a mucosal adjuvant that normally induces a Th2 response to bystander Ags. Taken together, these data suggest that, in this model of gluten hypersensitivity, deamidation is not a prerequisite for the initiation of gluten responses.
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PMID:Identification of immunodominant epitopes of alpha-gliadin in HLA-DQ8 transgenic mice following oral immunization. 1633 46