Fibrous proteins of normal and abnormal human epidermis.

Keratin proteins of human epidermis have been isolated from normal and abnormal tissues. The normal proteins whether removed from living layers (prekeratin) or from the stratum corneum (keratin) are shown to consist of three chains, molecular weights 65,000 (A), 60,000 (B) and 52,000 (C). When compared with the epidermal proteins isolated from abnormal tissues, differences can be detected in the electrophoretic pattern of the subunits. In general, relative amounts of the individual chains are altered and in specific cases or two of the polypeptides found normally are missing. All the alpha-fibrous proteins extracted are found to be very similar in amino acid composition.