Dissolution of bone by macrophages adhered on bone tissue

Abstract

We investigated the solubilization of bone tissue by macrophages, in terms of lactate production in vitro using bone particles which could not be engulfed by macrophages. The conditions during contact to bone tissue and phagocytosis were observed ultrastructurally. The results indicated that macrophages have soluble action to bone tissue when in contact with the tissue, as suggested by release of Ca, lactate production, rise of lactate dehydrogenase-activity and glucose consumption by macrophages. Significant correlation was also found between production of lactate by macrophages and Ca releases from bone tissue. Electron microscopic observation suggests that macrophages can dissolve bone particles which can then be phagocytized following destruction and solubilization of bone tissue.