> 95 % as determined by SDS-PAGE
< 1.0 EU per μg of the protein as determined by the LAL method
Measured by its ability to inhibit the biological activity of IGFII on MCF7 human breast adenocarcinoma cells (Karey, K.P. et al. (1988) Cancer Research 48:4083.).
The ED50 for this effect is typically 0.15-0.75 μg/mL in the presence of 14 ng/mL human IGFII.
A DNA sequence encoding the cynomolgus IGFBP3 (Gly28-Lys291) was expressed with a polyhistide tag at the N-terminus.
The recombinant heterodimer of cynomolgus IGFBP3 comprises 284 amino acids and has a calculated molecular mass of 31.1 KDa. The apparent molecular mass of the protein is approximately 41-44 KDa respectively in SDS-PAGE.
Lyophilized from sterile PBS, pH 7.4
1. Normally 5 % - 8 % trehalose, mannitol and 0.01% Tween80 are added as protectants before lyophilization. Specific concentrations are included in the hardcopy of COA.
2. Please contact us
for any concerns or special requirements.
In general, recombinant proteins are provided as lyophilized powder which are shipped at ambient temperature.
Bulk packages of recombinant proteins are provided as frozen liquid. They are shipped out with blue ice unless customers require otherwise.
Stability & Storage
Samples are stable for up to twelve months from date of receipt at -70℃
Store it under sterile conditions at -20℃ to -80℃. It is recommended that the protein be aliquoted for optimal storage. Avoid repeated freeze-thaw cycles.
A hardcopy of COA with reconstitution instruction is sent along with the products. Please refer to it for detailed information.
The Insulin-like Growth Factor (IGF) signaling system plays a central role in cellular growth, differentiation and proliferation. IGFBP3 is the most abundant IGF binding protein in human serum and has been shown to be a growth inhibitory, apoptosis-inducing molecule, capable of acting via IGF-dependent and IGF-independent mechanisms. It appears to function both by cell cycle blockade and the induction of apoptosis. IGFBP3 can be transported to the nucleus by an importin beta mediated mechanism, where it has been shown to interact with the retinoid X receptor alpha and possibly other nuclear elements. IGFBP3 antiproliferative signalling appears to require an active transforming growth factor beta (TGF-beta) signalling pathway, and IGFBP3 stimulates phosphorylation of the TGF-beta signalling intermediates Smad2 and Smad3. IGFBP3 has IGF-independent roles in inhibiting cell proliferation in cancer cell lines. Nuclear transcription factor, retinoid X receptor (RXR)-alpha, and IGFBP3 functionally interact to reduce prostate tumor growth and prostate-specific antigen in vivo. Several clinical studies have proposed that individuals with IGFBP3 levels in the upper range of normal may have a decreased risk for certain common cancers. This includes evidence of a protective effect against breast cancer, prostate cancer, colorectal cancer, and lung cancer. Moreover, IGFBP3 inhibits insulin-stimulated glucose uptake into adipocytes independent of IGF.
Baxter RC. (2001) Signalling pathways involved in antiproliferative effects of IGFBP-3: a review. Mol Pathol. 54(3): 145-8.Butt AJ, et al. (2001) IGFBP-3 and apoptosis--a license to kill? Apoptosis. 6(3): 199-205.Ali O, et al. (2003) Epidemiology and biology of insulin-like growth factor binding protein-3 (IGFBP-3) as an anti-cancer molecule. Horm Metab Res. 35(11-12): 726-33.Yamada PM, et al. (2009) Perspectives in mammalian IGFBP-3 biology: local vs. systemic action. Am J Physiol Cell Physiol. 296(5): C954-76.