Human IGFBP-4, His Tag (IG4-H52E4) is expressed from human 293 cells (HEK293). It contains AA Asp 22 - Glu 258 (Accession # P22692-1).
Predicted N-terminus: Asp 22
This protein carries a polyhistidine tag at the C-terminus.
The protein has a calculated MW of 27.9 kDa. The protein migrates as 33-37 kDa under reducing (R) condition (SDS-PAGE) due to glycosylation.
Less than 1.0 EU per μg by the LAL method.
>95% as determined by SDS-PAGE.
Lyophilized from 0.22 μm filtered solution in PBS, pH7.4. Normally trehalose is added as protectant before lyophilization.
Contact us for customized product form or formulation.
Please see Certificate of Analysis for specific instructions.
For best performance, we strongly recommend you to follow the reconstitution protocol provided in the CoA.
For long term storage, the product should be stored at lyophilized state at -20°C or lower.
Please avoid repeated freeze-thaw cycles.
This product is stable after storage at:
- -20°C to -70°C for 12 months in lyophilized state;
- -70°C for 3 months under sterile conditions after reconstitution.
Human IGFBP-4, His Tag on SDS-PAGE under reducing (R) condition. The gel was stained overnight with Coomassie Blue. The purity of the protein is greater than 95%.
Immobilized Human IGFBP-4, His Tag (Cat. No. IG4-H52E4) at 2 μg/mL (100 μL/well) can bind Human IGF-I, Fc Tag (Cat. No. IG1-H4269) with a linear range of 4-31 ng/mL (QC tested).
Insulin-like growth factor-binding protein 4 (IGFBP-4) is also known as IGF-binding protein 4, which contains an IGFBP domain and a thyroglobulin type-I domain. IGFBP-4 binds both insulin-like growth factors (IGFs) I and II and circulates in the plasma in both glycosylated and non-glycosylated forms. Binding of this protein prolongs the half-life of the IGFs and alters their interaction with cell surface receptors. IGFBP-4 is a unique protein and it consistently inhibits several cancer cells in vivo and in vitro. Its inhibitory action has been shown in vivo in prostate and colon. IGFBP-4 is secreted by all colon cancer cells.