The effect of etretinate on fibronectin in psoriatic skin.

The distribution of fibronectin in psoriatic skin was studied in 6 patients during treatment with oral etretinate using indirect immunofluorescence technique. In untreated lesions fibronectin was clearly visualized in the dermo-epidermal junction (DEJ) and in the walls of papillary capillaries, and showed a reticular or fibrillar pattern in the dermis. In the horny layer there was some fluorescence which we regarded largely as unspecific. In all patients a transient accentuation of fibronectin accumulation in DEJ was seen after 3-7 days of treatment. Except for some decrease in the amount and intensity of capillary fluorescence, no other notable changes occurred in the fibronectin distribution during 4 weeks of treatment.