Hu Osteopontin, 100 _g

This recombinant human cytokine from STEMCELL Technologies is Osteopontin (OPN), also known as secreted phosphoprotein 1 (SPP1), a member of the SIBLING family of glycoproteins. The protein is expressed in HEK293 cells with a polyhistidine tag at the N-terminus and is initially secreted as a 317 amino acid protein subject to tissue-specific post-translational modifications by glycosylation, phosphorylation, and transglutamination. Alternative names include BNSP, BSPI, ETA-1, OPN, and SPP1, and the expressed construct covers Ile17–Gly166 (accession NP_001035147.1).

The product is supplied as a lyophilized powder from sterile PBS, pH 7.4, with trehalose (5 - 8%), mannitol, and 0.01% TWEEN® 80 added as protectants before lyophilization. Human Recombinant Osteopontin has a predicted molecular mass of 20.64 kDa but an apparent molecular mass of 35 kDa due to glycosylation, as shown by SDS-PAGE analysis under reducing and non-reducing conditions with Coomassie Blue staining. Purity is ≥ 92% and the endotoxin level is ≤ 1 EU/μg protein as determined by kinetic Limulus amebocyte lysate (LAL) analysis. Activity data is not available.

Osteopontin is expressed in and secreted by a wide range of cells and plays an important role in cell signaling, migration, and activation. It also functions as a T-helper 1 cytokine and has been shown to regulate inflammation both in vitro and in vivo. The protein has been implicated in the pathophysiology of various cancers, including prostate, lung, ovarian, and breast cancer. The product is stable as supplied for 12 months from the date of receipt when stored at -20 to -80°C, and should be reconstituted in sterile PBS (pH 7.4) to at least 0.25 mg/mL without vortexing.