Expression of Skin Sulfhydryl Oxidase in Normal Skin , Cultured Skin and Several Abnormally Keratinizing Dermatoses

Kim, Ki Ho; Eun, Hee Chul

Abstract

BACKGROUND: Skin sulfhydryl oxidase(SSO) is the enzyme catalyzing the covalent crosslinking of the protein molecules via disulfide bond formation, which is probably responsible for the formation of tight and stable structures in the skin tissues, However, the lack of its gene cloning and antibody preparation limited the study for the role of the enzyme in the tissues.
OBJECTIVE
It is required to study the role of the enzyme in the normal skin tissues and several dermatosis with abnormal keratinization and its regulation by several materials and drugs in the culture models.
METHODS
We performed immunohistochemical analysis to determine the localization and expression of the enzyme in the normal skin and mucosa and hair tissues and in the skin explant cultures and artificial skins with irritant- and differentiation modifieradded conditions.
RESULTS
In the skin, SSO was most strongly expressed in the granular layers and mostweakly in the basal layers. The similar but weaker expression pattern was observed in the mucosa with stronger expression in the upper flattened layers compared to the lower layers. In the hair, it was expressed in the inner and outer root sheaths at the isthmus portion in weaker stainable patterns. The strong expression of SSO was not observed beneath the Monro microabscess or parakeratosis in the involved aren of psoriasis. In actinic keratosis and Bowen disease, it was expressed more strongly in the dyskeratotic cells or parakeratotic areas. And in the horn pearls of the squamous cell carcinoma, the strong expression of SSO was observed. In the skin ezplant culture, the expression of SSO is induced by treatment with sodium lauryl sulfate or retinoic acid with more extended stained areas compared to the control. In contrast, its expression is not basically modified on the cellular level but inhibited dynamically by a decrease of the granular layers with retinoic acid in the artificial skin(raft culture).
CONCLUSION
And the inducibility of the enzyme by the irritating agents in the skin organ explant culture suggests the role of the enzyme as one of skin defense system. The decrease of granular layers by retinoic acid in the artificial skin(raft culture) reflects the fact that its expression can be inhibited indirectly during the keratinization process. Therefore, it can be summarized that SSO is the enzyme involved in the keratinizing process of skin tissues as well as the protective function for the skin tissues.