Osteoprotegerin ELISA

Osteoprotegerin (OPG) or osteoclastogenesis inhibitory factor (OCIF), a product of the TNFRSF11B gene located in chromosome 8q24, is a member of the TNF receptor superfamily that plays a key role in bone remodeling. Human OPG is a 401 amino acid secreted glycoprotein that exists naturally as either a 120 kDA disulfide-linked homodimer or 60 kDa monomer. OPG is active as either a monomer or dimer, with the dimer showing more potent bioactivity. Unlike most members of the TNF receptor superfamily, OPG aparently exists only in a soluble form as a decoy receptor for its ligands, RANKL (TNFSF11, OPGL, ODF, TRANCE) and TRAIL. Human OPG shares 85% and 86% amino acid identity to mouse and rat OPG respectively. In human adults, OPG mRNA is highly expresed in various tissues, e.g. bone, skin, liver, stomach, intestine, heart, brain and lung. Osteoprotegerin inhibits the binding of RANKL to RANK (osteoclast differentiation and activation receptor, ODAR) on the osteoclast surface and thus, OPG is a natural antagonist to RANKL-induced osteoclastogenesis and bone resorption. Since OPG exhibits an inhibitory effect on osteoclasts, it acts as a soluble factor in the regulation of bone mass. Osteoclast formation activity may be monitored principally by determination of the concentration ratio of RANKL/OPG. Alteration of this ratio may be the cause of bone loss in many imbalances in bone metabolism such as osteoporosis, osteopetrosis, hypercalcemia, metastatic osteolytic lesions and rheumatic bone degradation. Product distributed by Tecan. IBL International GmbH. For the QC certificate, please kindly download directly from the homepage www.biovendor.com, entering the lot number in the search field.