Production of antibodies to gliadin by peripheral blood lymphocytes in children with celiac disease: The use of an enzyme-linked immunospot technique for screening and follow-up

Problems in the diagnosis of celiac disease are that a long time is needed between challenge with gluten and the appearance of the typical diagnostic morphologic signs in gut mucosa. Furthermore, local immunity to gliadin is only slowly and often incompletely mirrored by serum IgA anti-gliadin antibody (AGA) levels. It is known that a local IgA-associated immune response in the gut may be better and more quickly mirrored by an increase of circulating IgA-producing cells against the immunogen than by IgA serum antibodies. We have therefore used an enzyme-linked immunospot (ELISPOT) assay to enumerate IgA AGA spot-forming cells (SFC) in peripheral blood in 82 children with suspected celiac disease or with other gastrointestinal symptoms. The numbers of IgA AGA SFC/10(6) mononuclear cells were markedly increased in 17 patients with untreated (and later biopsy-verified) celiac disease compared with healthy children, children with nonceliac disease, and patients treated for celiac disease (p < 0.0001). In 20 children with celiac disease the numbers of IgA AGA SFC increased rapidly (p < 0.0001) after gluten challenge. As early as 2 wk after gluten challenge, 15/20 of these patients had abnormal levels of IgA AGA SFC, 6/20 patients had increased levels of serum IgA AGA, and 7/20 had IgA anti-endomysium antibodies. Our results indicate that analysis of IgA AGA production in peripheral blood cells may in further clinical studies provide a sensitive method for the diagnosis of celiac disease after a short time of gluten challenge.