TNFRSF11B, also known as Osteoprotegerin (OPG)/Osteoclastogenesis Inhibitory Factor (OCIF), is a member of the tumor necrosis factor receptor superfamily that lacks any apparent cell association motifs and exists as a soluble secreted protein. Natural TNFRSF11B/OPG/OCIF has been found to exist predominantly as disulfide linked dimers. Two TNF superfamily ligands, RANKL (receptor activator of NFκB ligand) and TRAIL (TNF related apoptosis inducing ligand), have been shown to be the cellular ligands for TNFRSF11B. TNFRSF11B acts as decoy receptor for RANKL and thereby neutralizes its function in osteoclastogenesis. TNFRSF11B inhibits the activation of osteoclasts and promotes osteoclast apoptosis in vitro. It may also play a role in preventing arterial calcification. TNFRSF11B may act as decoy receptor for TRAIL. TRAIL binding blocks the inhibition of osteoclastogenesis.

·Description
Recombinant Human TNFRSF11B produced by transiently transfected human cell is a secreted protein with sequence (Accession#O00300)(Glu22-Leu401) of human TNFRSF11B fused with a polyhistidine tag at the C-terminus.

·Quality Control

Biological activity:
The ED50 of recombinant TNFRSF11B is 8-24ng/mL in the presence of 12 ng/mL crosslinked rhTRAIL as measured by its ability to inhibit TRAIL mediated cytotoxicity using L929 mouse fibrosarcoma cells treated with TRAIL.

Purity: Greater than 90.0% as determined by:
(a) Analysis by RP-HPLC.
(b) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.
Amino-Acid Sequence: Predicted N terminal amino acid is Glu22.
Endotoxin:Less than 0.1ng/μg (1EU/μg) of rHu TNFRSF11B.

·Formulation
Sterile and Lyophilized from a 0.2 μm filtered solution in PBS.

·Reconstitution
It is recommended to reconstitute the lyophilized rHuTNFRSF11B in sterile water not less than 100μg/ml.

·Storage
Lyophilized rHu MMP3 although stable at room temperature for 3 weeks, should be stored Lyophilized rHuTNFRSF11B although stable at room temperature for 3 weeks, should be stored desiccated below -18°C. Upon reconstitution rHuTNFRSF11B should be stored at 4°C between 2-7 days and aliquots of reconstituted samples containing 0.1% BSA are stable up to 3 months below -18°C for future use.

Please avoid freeze-thaw cycles.