Biologically active substances of skin affecting proliferation and differentiation of human keratinocytes in culture

The development of new therapeutic agents for use in the treatment of psoriasis is associated with the isolation and purification of dermal peptides, and also the creation of their synthetic analogs [11]. The leading mechanism of disturbance of proliferation of the epidermis in psoriasis is removal of the basal ceils from the influence of the system of proliferative regulation. We know that many interdependent factors, including several synthesized by cells of the proliferating tissues themselves, are involved in the regulation of cellular proliferation [5, 13, 17]. With the development of epidermal cell culture techniques, test systems based on cultures of normal and malignant human and animal keratinocytes have achieved widespread popularity [8, 14, 18]. Numerous investigators have shown that epidermal ceils in culture react to various regulators of cellular proliferation and differentiation, in the same way as epidermal cells in vivo [2, 6, 7]. Processes of growth predominate over differentiation in cultures of keratinocytes, which distinguishes them from the normal epidermis and more closely resembles the skin lesions of psoriasis [3]. The transition from proliferating cells in culture into the differentiated state is accompanied by a whole range of morphological and biochemical changes, characteristic of differentiation of the epidermis, namely the progressive increase in size of the cells, changes in the keratin profile, and the formation of ketatin membranes, clue to activation of cae+-dependent transglutaminase [4]. The aim of this investigation was to study the effect of biologically active substances of skin on growth and differentiation of human epidermal cells in culture.