Cell Proliferation in the Lichen Planus Infiltrate

Abstract

In 7 patients suffering from lichen planus (LP) light microscopic and EM 3H-thymidine (3HT) labeling studies were performed and the following results were obtained. Using the light microscope, a large number of 3HT labeled cells can be observed in the dermal infiltrate of LP. Most of the labeled nuclei belong to mononuclear, round cells while isolated endothelial cells, fibroblasts, histiocytes and mast cells could be found labeled. The mean labeling index of round cells in the patients was 4.27 .+-. 1.57%. The evaluation of the EM autoradiographs showed that, as far as round cells were concerned, nuclei of cells showing the morphological criteria of stimulated lymphocytes were labeled exclusively. In LP, as in allergic contact dermatitis, a high proliferative activity of lymphocytes apparently takes place.