TOPICAL CALCIPOTRIOL FOR PSORIASIS - AN IMMUNOHISTOLOGIC STUDY

The aim of the present study was to investigate the distribution of La ngerhans cells and T cells in the lesions and also the phenotypic expr ession of ma!kers of activation on lesional T cells and keratinocytes, before and after 2 weeks of topical treatment of 7 psoriatic patients with calcipotriol. Before treatment, the infiltrate was composed main ly of T cells and there was decreased expression of CD1 on the intra-e pidermal Langerhans cells. ICAM-1 and EGF receptor were present throug hout the epidermis, but keratinocytes expressing Transferrin receptor were detected only in the basal layer. After 14 days of calcipotriol t herapy, there were significantly fen-er CD4T cells in the dermis and a n increased number of intraepidermal CD1 + Langerhans cells. ICAM-1 ex pression on lesional keratinocytes was reduced in all patients, but th e expression of EGF receptor was decreased in 3 patients only, and Tra nsferrin receptor expression on keratinocytes had not changed. All the se changes were concurrent with moderate clinical improvement of the l esions. The results suggest that in the early stages of the clinical r esponse to calcipotriol there is an immunomodulating effect of the dru g associated with variable decreases in keratinocyte expression of mar kers of activation.