Immunohistochemical Study of Thrombomodulin in Experimental Cholesteatoma

Abstract

BACKGROUND AND OBJECTIVES: The hyperproliferative character of human cholesteatoma epithelium was confirmed through various hyperproliferation associated antibody expressions. Among the various approaches for evaluating proliferative activity, thrombomodulin (TM) is a cell surface glycoprotein which forms a high affinity non-covalent complex with thrombin and is a differentiation marker for spinous layer keratinocytes. Several animal models have been introduced to study cholesteatoma pathogenesis, among which canal ligation model using Mongolian gerbils is of much interest, because it can potentially provide information on cell differentiation and proliferation of cholesteatoma. In this study, we investigated the hyperproliferative characteristics of canal ligation cholesteatoma by comparing deep meatal skin and retroauricular skin. Another purpose of this study was to provide the morphological basis for further animal studies concerning cholesteatoma pathogenesis. MATERIALS AND METHOD: Using immunohistochemical technique with anti-monoclonal antibody, we investigated TM expression in the canal ligation cholesteatoma, deep meatal skin and retroauricular skin of Mongolian gerbil. RESULTS: Experimental cholesteatoma induced by canal ligation and deep meatal skin showed TM expression especially in the suprabasal layers. TM expression of experimental cholesteatoma is much more intense than that of deep meatal skin. CONCLUSION: Experimental cholesteatoma revealed an altered differentiation in suprabasal layer, suggesting that this animal model can be used for further study in the epithelial differentiation and proliferation of cholesteatoma.