Class-specific antibodies to gluten in dermatitis herpetiformis.

An immune reaction to wheat protein has been previously proposed to explain the pathogenesis of dermatitis herpetiformis. In order to detect and characterize antibodies to gluten in human sera, we developed an enzyme immunoassay for class-specific antibodies. Results of this assay in 49 patients with dermatitis herpetiformis were compared with those of 38 normal control subjects, 11 patients with celiac disease, and 6 small-bowel bypass patients. IgA antibodies to gluten were significantly more frequent in dermatitis herpetiformis sera (28/49) than in normal control sera (4/38). IgG antibodies to gluten were significantly more frequent in both celiac disease (10/11) and dermatitis herpetiformis (16/49) sera than in control (5/38) sera. Dermatitis herpetiformis sera also had an increased prevalence of IgM antibodies to gluten (19/49). Small-bowel bypass patients demonstrated no antibody to gluten. Antibodies to gluten in dermatitis herpetiformis objectively mark a state of immune reactivity to wheat protein and may be involved in the genesis of the cutaneous IgA immune deposits and the skin disease.