Influence of genetic factors on the serum levels of antigliadin antibodies in celiac disease.

Abstract

The relationship between titers of antigliadin antibodies (IgA class and total immunoglobulins IgA, IgG, and IgM) and HLA-DR antigens was studied in two random samples of unrelated Spanish children with celiac disease. One of these groups had been on a gluten-free diet for at least 6 months and the other had been given a similar regimen followed by at least 6 months on a gluten-containing diet. Children with celiac disease who had the DR7 antigen but not DR3 showed significantly higher antigliadin antibody titers on a gluten-containing than on a gluten-free diet, whereas those with DR3 but not DR7 did not show this difference. With respect to DR phenotypes, the children with DR3/DR7 and DR7/DR5 phenotypes had significantly higher antibody titers while consuming gluten than when on a gluten-free diet. However, children with celiac disease with the DR3/DR3 phenotype showed similar antigliadin antibody titers on both diets. The present results suggest that genetic factors in the DR region influence the humoral immune response to gliadin in celiac disease.