Immunoassay for detection of IgA antitissue transglutaminase in patients with celiac disease.

Celiac disease is characterized by mucosal changes in the small intestine, ranging from increased numbers of intraepithelial lymphocytes to complete villus effacement with various signs of malabsorption (1,2). Celiac disease is diagnosed by the demonstration of an altered intestinal mucosa in a jejunal biopsy specimen (3). Celiac disease patients invariably have antibodies directed against gliadin and endomysium, a structural component of the extracellular matrix: both antibodies disappear under a gluten-free diet. Therefore, these antibodies are useful tools for diagnosis, and in the dietary control of coeliac disease (3-7). Serum IgA antibodies against endomysial antibodies (EMAs) are especially considered to be sensitive and highly specific markers for celiac disease (8)(9). Previously, EMAs were detected by indirect immunofluorescence on tissue slides of monkey esophagus or human umbilical cord (10-12).