Failure to detect gliadin or gliadin binding sites in the skin of patients with dermatitis herpetiformis: immunofluorescence, organ culture and autoradiographic studies.

Recent investigations indicate an abnormal binding of gluten or gliadin to lymphocytes or intestinal mucosa cells in gluten sensitive enteropathy. Since dermatitis herpetiformis is closely associated to gluten sensitive enteropathy, similar receptors could also exist in the skin of patients with dermatitis herpetiformis. To prove this hypothesis, skin of normal volunteers and uninvolved skin of 3 patients with dermatitis herpetiformis was investigated for the presence of gliadin and gliadin binding sites. In vivo bound gliadin was not found by direct immunofluorescence using 3 different rabbit antigliadin antisera. In order to test skin for gliadin binding sites, normal sera and autologous dermatitis herpetiformis sera containing 25 mg% gliadin and tritium labeled gliadin, respectively, were used for incubation of normal and dermatitis herpetiformis skin cryocut sections and of normal and dermatitis herpetiformis skin specimens, grown under organ culture conditions. As checked by direct immunofluorescence and autoradiography, there was no specific in vitro binding of gliadin, indicating that gliadin does not fix to normal human or dermatitis herpetiformis skin. Thus, the role of gliadin in the fixation in vivo, of antibodies or immune complexes to skin in dermatitis herpetiformis, remains obscure.