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SUMMARY Antibodies to the baker's yeast Saccharomyces cerevisiae (ASCA), recently proposed as a serological marker of Crohn's disease, have also been detected in other autoimmune disorders. The aim of this study was to determine prevalence and clinical significance of ASCA in autoimmune liver disease. The presence of IgG and IgA ASCA was evaluated using a commercially available immunoassay in 215 patients with autoimmune liver disease (primary biliary cirrhosis, PBC, 123 cases; autoimmune hepatitis, AIH, 67 cases; primary sclerosing cholangitis, PSC, 25 cases), 48 with inflammatory bowel disease and 19 healthy blood donors. Anti neutrophil cytoplasmic antibodies with the perinuclear pattern (p-ANCA) were assessed by indirect immunofluorescence in PSC patients. The main clinical and biochemical parameters between ASCA-positive and negative patients were analysed and compared. ASCA are predominant in Crohn's disease (70%); among liver patients, PSC and AMA-negative PBC show the highest ASCA prevalence (53% and 44%). In PBC ASCA correlate with higher levels of circulating IgA (P < 0·05). In PSC the detection of either ASCA or p-ANCA is neither associated with any clinical or biochemical feature, nor with an underlying inflammatory bowel disease. ASCA can not be considered an additional serological marker of autoimmune liver disease, but the possibility of detecting such a reactivity in autoimmune liver disorders should be considered; their correlation with elevated IgA in PBC suggests that ASCA may be an indirect sign of enhanced mucosal immunity; in PSC patients neither ASCA nor p-ANCA predict the occurrence of a concomitant inflammatory bowel disease. [ABSTRACT FROM AUTHOR]

Explores the activation of signal-transducer and activator of transcription 1 (STAT1) protein in pouchitis, a gastrointestinal disease. Increase in the production of proinflammatory cytokines; Role of STAT1 in the pathophysiology of the disease.

Production of leucocyte migration inhibition factor by peripheral blood leucocytes in response to challenge with gluten fractions has been proposed as a reliable in vitro test for the diagnosis of coeliac disease. We have performed the leucocyte migration inhibition test with two different gluten fractions, GFIII and B2, in untreated and treated coeliac patients, patients with other intestinal diseases (abnormal controls) and healthy controls, and evaluated the sensitivity, specificity and positive and negative predictability of the test for the diagnosis of coeliac disease. Using GFIII as antigen leucocyte migration was significantly inhibited, compared to healthy controls, not only in treated and untreated coeliacs but also in abnormal controls. Using B2 gluten subfraction as antigen only treated coeliacs and abnormal controls differed significantly from healthy controls. The elevated number of abnormal controls showing migration inhibition consistently affected the diagnostic value of the test, which did not vary using B2 subfraction instead of GFIII as antigen. Our study confirms previous observations of gluten sensitization, as detected by leucocyte migration inhibition, in coeliac patients but strongly questions the claim that coeliac disease can be diagnosed on the basis of a positive leucoc!te migration inhibition test without the need for intestinal biopsy. [ABSTRACT FROM AUTHOR]