Anti-IGFBP5 (Insulin-like Growth Factor-binding Protein 5, IBP-5, IGF-binding Protein 5, IGFBP-5, IB

The insulin like growth factors (IGFs) are the major growth- promoting factors in the plasma. IGFs are secreted by a variety of cells and exert a multitude of effects on cellular survival, growth and differentiation. The A and B domains of IGFs are identical to insulin. IGF initiates their biological action through binding to the type IGF receptor (IGF-1R), a heterotrimeric protein complex with a tyrosine kinase activity. The IGF-IIR lacks the kinase activity and is actually identical to the mannose- 6-phophate receptor. Unlike most other peptide hormones, IGFs are complexed with specific binding proteins in the plasma known IGF Binding proteins (IGFBPs). At least 6 related IGFBPs (IGFBP1-6) have been well characterized. Recently, IGFBP-7/Mac25/prostacyclin- stimulating factor (PSF)/tumor adhesion factor (TAF) was originally identified as a cDNA derived from leptomeninges. These proteins are present in plasma in high concentration as compared to the membrane IGFRs. Therefore, IGFBPs have the potential to modulate the IGF action. IGFBPs have been shown to either inhibit or stimulate the IGF effects. The primary structures of mammalian IGFBPs appear to contain three distinct domains of roughly equivalent sizes: the conserved N-terminal domain, the highly variable mid region, and the conserved C-terminal domain. Human IGFBPs share approximately 36% identity. Human IGFBP-5 is a 252aa mature protein that is expressed by fibroblasts, myoblasts and osteoblasts, making it the predominant IGFBP found in bone extracts. IGFBP-5 has a strong affinity for hydroxyapatite, allowing it to bind to bone cells. When bound to extracellular matrix, IGFBP-5 is protected from proteolysis and potentiates IGF activity, but when it is soluble, IGFBP-5 is cleaved to a biologically inactive 21kD fragment. , Applications:, Suitable for use in ELISA. Western Blot, though not tested, may potentially be used as an application. Other applications not tested. Recommended Dilution: Western Blot: 1-2ug/ml, ELISA: 1:10,000 (using 50-100ng control peptide/well), Optimal dilutions to be determined by the researcher. Storage and Stability: Lyophilized powder may be stored at -20°C. Stable for 12 months at -20°C. Reconstitute with sterile ddH2O or PBS. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 12 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.