Flow-cytometric characterization of normal versus psoriatic epidermis using improved cell separation methodology

Recently a new approach for epidermal cell characterization was developed: three-parameter flow cytometrical analysis of pure and complete epidermal cell suspensions prepared from punch biopsies followed by dermoepidermal separation by thermolysin. The aim of the present communication is the comparison between psoriatic lesional skin and normal skin using this new approach with respect to the percentage of suprabasal keratinocytes (keratin 10+ cells), mesenchymal cells, including the infiltrate cells (vimentin+ cells) and the percentage of basal cells in SG2 M phase, in order to validate this methodology in studies on psoriatic skin. Punch biopsies were taken from 7 healthy volunteers and in 7 psoriatic patients 4 biopsies were taken in each of them from comparable lesions. The present study reconfirmed that the percentage of basal keratinocytes in psoriasis was increased and the percentage of keratin 10+ cells was substantially decreased as compared to normal skin. The new methodology revealed data with a narrow range. In psoriatic lesional skin the intra individual variation was less compared to the inter individual variation.