Acquired and Congenital Cholesteatoma: Determination of Tumor Necrosis Factor-alpha, Intercellular Adhesion Molecule-1, Interleukin-1-alpha and Lymphocyte Functional Antigen-1 in the Inflammatory Process

Abstract

The molecular and cellular factors resulting in the pathologic features of acquired and congenital cholesteatomas are not completely known. Recently, proinflammatory cytokines like interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor-alpha (TNF-alpha) have been shown to induce bone resorption, in vitro. To elucidate the key molecules involved in bone resorption and cell infiltration associated with cholesteatoma, we examined the in vivo levels of IL-1 alpha and TNF-alpha, intercellular adhesion molecule-1 (ICAM-1) and lymphocyte functional antigen-1 (LFA-1) in acquired and congenital cholesteatomas, by reverse transcriptase-polymerase chain reaction, immunohistochemistry, and ELISA. Increased levels of IL-1 and TNF-alpha were detected in both types of cholesteatomas as compared to normal skin. Increased ICAM-1 expression and LFA-1+ cells were detected in acquired but not congenital cholesteatoma. Strong correlation was detected between TNF-alpha and bone resorption in both types of cholesteatoma, and between TNF-alpha and ICAM, TNF-alpha and severity of infection, or cell infiltration in acquired cholesteatoma. No correlation existed between various parameters and IL-1 alpha. These results suggest that TNF-alpha may play a crucial role in the pathogenesis of both acquired and congenital cholesteatomas by regulating bone resorption and cell infiltration.