T lymphocytes bearing the gamma/delta T-cell receptor in cutaneous lesions of dermatitis herpetiformis

T lymphocytes bearing the gamma/delta T-cell receptor are a rare component of normal human GI epithelium and skin. Recently, however, an unusually high percentage of T lymphocytes with gamma/delta receptors has been described in gastrointestinal biopsies from patients with dermatitis herpetiformis, implicating the gamma/delta T cell subset in the pathogenesis of this disease. We investigated a possible role for this subset of lymphocytes in the pathogenesis of the cutaneous lesions of dermatitis herpetiformis. Using a standard immunoperoxidase technique, we labelled perilesional skin biopsies from patients with dermatitis herpetiformis and other inflammatory dermatoses with monoclonal antibodies to CD3, CD4, CD8, alpha/beta T cell receptor, gamma/delta T cell receptor, and IL-2 receptor. We found no differences in the percentage of gamma/delta positive T lymphocytes in skin lesions of dermatitis herpetiformis as compared to other selected inflammatory conditions. These findings suggest that the pathogenesis of the cutaneous lesions of dermatitis herpetiformis is not mediated through gamma/delta T cells, and that the cutaneous lesions may develop through mechanisms different from those operative in the gastrointestinal tract.