| [ Summary ] |
Osteoclasts are terminally differentiated cells derived from hematopoietic stem cells or monocyte / macrophage lineage cells. The most characteristic feature of osteoclasts is multinucleation by cell-cell fusion of mononuclear osteoclasts. In order to isolate the cell-cell fusion-inducing molecule in osteoclasts, we undertook DNA subtraction screening between multinuclear osteoclasts and mononuclear macrophages. It was found that DC-STAMP was highly expressed in osteoclasts compared with macrophages. To understand the role of DC-STAMP in vivo, DC-STAMP deficient mice were generated. DC-STAMP deficient mice show a complete lack of cell-cell fusion of osteoclasts and foreign body giant cells. It was also found that DC-STAMP is an essential cell-cell fusion regulator in macrophage lineage cells. |