Serum antibodies to wheat germ agglutinin and gluten in patients with dermatitis herpetiformis.

It has been speculated that gluten may play a role in the pathogenesis of dermatitis herpetiformis (DH) because it can act as a lectin. The lectin activity of gluten preparations was recently identified as wheat germ agglutinin (WGA). IgG and IgA serum antibodies to WGA and gluten were therefore measured in patients with DH and coeliac disease (CD) by an enzyme-linked immunosorbent assay (ELISA). Compared with healthy controls, both patients categories had increased IgG and IgA activities to WGA and gluten, the CD group showing the highest antibody levels. DH patients with subtotal villous atrophy tended to have higher activities than those with no villous changes or only minor changes. No significant difference in the gluten-to-WGA ratio of IgA or IgG antibodies was found when DH patients were compared with CD patients. If WGA plays a pathogenetic role in DH, then DH patients must have dermal characteristics, as yet undefined, that explain the initiation of their skin disease.