Sds‐page Analysis of Whole and Fractionated Psoriatic Epidermis

Abstract

The SDS‐PAGE patterns of keratinous proteins extracted from whole epidermis and fractionated epidermal cells were studied. Those from the whole and fractionated epidermal cells of psoriatic involved skin showed an extra 58,000 dalton polypeptide in addition to the four major polypeptides (M.W.: 67,000, 63,000, 59,000 and 55,000) which were demonstrated to be common to normal epidermis and psoriatic‐uninvolved epidermis. The stratum corneum of psoriatic involved skin did not contain a 67,000 dalton polypeptide which was present in the stratum corneum of normal and psoriatic uninvolved skin. The presence of the additional 58,000 dalton polypeptide may be due to abnormal synthesis of keratin proteins in the psoriatic epidermis, since this additional polypeptide was present in the lower living layers of the psoriatic epidermis as well. On the other hand, the absence of the 67,000 dalton polypeptide in the psoriatic stratum corneum may be due to enzymatic modifications during the transition from the living cell layers to the horny layer.