Effect of Hydrocortisone on the Keratinization of Chick Embryonic Skin cultured in a Chemically Defined Medium

Abstract

DURING keratinization of the epidermis—a process of cell maturation—synthesis of specific protein(s) within the cells is accompanied by degradation of the cellular constituents. Hormones may be involved as controlling factors. This has been one of the most attractive topics of tissue culture studies ever since Strangeways and Fell¹ cultured chick embryonic skin by the watchglass method using a natural plasma clot medium. Later, Fell et al.^2,3 found that hydrocortisone accelerated the keratinization of chick and rat embryonic skin cultured on a plasma clot. Chemically defined media have been used successfully for cultivating rat⁴, chick^5,6 and human⁷ foetal skin, and Wessells⁵ demonstrated that thyroxine initiated keratinization of the epidermis of chick embryonic skin growing in such media. These histological findings suggest that hormones are probably important in keratinization in embryonic development.