Immunohistochemical Staining of S - 100 Protein in Human Fetal Skin

Chung, Byung Soo; Chung, In Ae; Hwang, Sun Wook

Abstract

The authors attempted to examine the distribution of S-100 protein in the human fetal skin. Immunohistochemical staining(ABC rnethod) using anti-S-100 antibodies was carried out on skin specimens taken from 11 human fetuses ranging from 9 weeks to 27 weeks of estimated gestational age. At 9 weeks of estimated gestational age, the embryonic epidermis consisted of three cell layers,' the basal layer, intermediate layer and periderm, all of them being stained for S-100 protein. But after 18 weeks, the basal layer changed to be negative. Granular and cornified layer's, beginning their development at 22 weeks, were not stained for S-100 protein. Hair germ of 12 week-fetuses was recognized unstained as a bulge of basal cells. In fully differentiated structural components of the hair follicle after 18 weeks, the outer root sheath only was stained for S-100 protein whereas the inner root sheath, hair matrix cells and sebaceous glands were unstained. Eccrine gland germs developed at 12 weeks of embryonic life as undulation of the basal layer and were not, stained. And at 22 weeks, the secretory portion of the eccrine glands were formed in the dermis and stained for S-100 protein. Our present study suggests that the expression of S-100 protein can undergo considerable changes during ernbryonic differentiation in the epidermis and epidermal appendages.