Osteoclast differentiation factor in human osteosarcoma cell line

A sensitive sandwich enzyme-linked immunosorbent assay (ELISA) for human os teoclast differentiation factor (ODF/RANKL/OPGL/TRANCE) utilizing a polyclo nal antibody that recognizes both human soluble ODF and mouse ODF in combin ation with a osteoclasogenesis inhibitory factor (OCIF/OPG) was developed. We can quantify the ODF level in not only human ODF (detection limit: 0.05 ng/ml), but also mouse ODF by virtue of cross-reactivity; Employing this as say system, we demonstrated that ODF is constitutively present as a membran e-bound form in both the human osteosarcoma cell lines, MG-63, HOS and SaOS -2, and the mouse osteoblastic cell line MC3T3-E1.