Subpopulations of T lymphocytes in peripheral blood and in skin lesions in lichen ruber planus.

Peripheral blood lymphocytes and different immunocompetent cells of the cutaneous inflammatory infiltrate were characterized by reactivity with monoclonal antibodies directed to surface antigens of T lymphocytes and Langerhans cells by means of the indirect immunofluorescence technique in 10 patients suffering from lichen ruber planus. In contrast to the controls (n = 10), lichen patients had a significantly reduced percentage of the suppressor/cytotoxic T cell subset in peripheral blood (p less than 0.002). At the dermoepidermal junction suppressor/cytotoxic T lymphocytes and Langerhans cells predominated. Some possible conclusions are discussed.