Failure to detect specific gluten antigens associated with the immune aggregates in the skin in dermatitis herpetiformis.

The univolved skin of 10 patients with dermatitis herpetiformis (DH) was examined for the presence of gluten antigens with the immunofluorescence technique using a rabbit anti-gliadin antiserum, human antibodies to wheat and to reticulin conjugated to fluorescein-isothiocyanate (FITC) and class-specific anti-human IgA immunoglobulin. In all patients, IgA deposits were found in the tips of the dermal papillae of the uninvolved skin. With the anti-wheat and anti-reticulin conjugates, as well as with the rabbit anti-gliadin antiserum, no specific immunofluorescence was observed in any of the skin specimens. Skin biopsy sections of three DH patients were treated with an acid solution (pH 3.2) in an effort to dissociate antigen-antibody complexes that might be present. After the elution procedure the sections showed undiminished IgA fluorescence, and retesting with the anti-wheat- and anti-reticulin antisera again gave negative results. The skin eluates, two of which contained IgA, had no antibodies to wheat or reticulin. These findings do not give support to the hypothesis that the antigens in the suspected immune complexes in the DH skin consist of gluten.