Immunofluorescent serum gliadin antibodies in children with coeliac disease and various malabsorptive disorders

Abstract

Using an immunofluorescent gliadin antibody assay with gliadin-coated red cells, it was possible to determine immunoglobulin classes as well as immunogenic fractions of wheat protein. In 80 coeliac children under various dietary conditions, the main immunoglobulin class of serum gliadin antibodies was shown to be IgG. Low titres of IgM-antibodies were demonstrated in 93% of coeliac children on a normal diet and in 67% of them on a gluten-free diet. IgA-antigliadin was detected in 27%, and IgE antibody in 4% of coeliac children with an initially “flat” jejunal mucosa.

Wheat protein fractions were prepared by ion exchange chromatography on CMC and identified by polyacrylamide electrophoresis at pH 2.3. Using these fractions in the antibody test system, human serum gliadin antibodies were shown to be directed against noxious alpha-gliadin, as well as against harmless wheat albumins and globulins, in all the groups tested—including controls. There was no major subpopulation of gliadin antibodies which could be shown to be strictly confined to coeliac disease. A divergence of the pathogenic and immunogenic properties of wheat proteins was clearly established. Cow's milk precipitins were demonstrated in parallel with gliadin antibodies in many coeliac children, but they were shown to occur frequently in malabsorptive and normal controls. Investigation of gliadin antibody specificity did not reveal any substantial proof for a primary pathogenic significance of immunofluorescent gliadin antibodies in coeliac disease.