- H Sudhoff: Hals-Nasen-Ohrenklinik der Ruhr-Universität Bochum, St. Elisabeth Hospital, Bochum, Germany. Holger.Sudhoff@ruhr-uni-bochum.de
BACKGROUND: The pathology associated to cholesteatoma is predominantly a consequence of osteoclast-mediated bone resorption within the middle ear. To assess its pathogenesis a murine model for dermal-implant induced osteolysis was evaluated for the expression of osteoclast stimulating and differentiating factors.
METHODS: Mouse calvaria were analysed for the expression of osteoprotegerin ligand (OPGL), osteoprotegerin (OPG) and macrophage-colony stimulating factor (M-CSF) using immunohistochemistry. The detection of osteoclast cell lineage was acquired by immunohistochemistry using markers CD 4, CD 11a, CD 11b, CD 14, CD 51, CD 68 and TRAP.
RESULTS: An increased expression of the investigated cytokines M-CSF, OPG and OPGL was demonstrated by immunohistochemistry. The presence of osteoclast precursor cells and mature resorbing osteoclasts was confirmed in time-dependent manner triggered by dermal implantation.
CONCLUSIONS: This study reveals the basic events in osteoclast biology in localized inflammatory bone resorption and provides new insights into the comprehension of cholesteatoma-induced bone resorption.