Recombinant Human IGFBP3

Human Insulin-like Growth Factor Binding Protein-3 (hIGFBP-3) is a 264 amino acid protein that is one of the six iclassicali IGF binding proteins that play an important role in stabilizing and regulating the activity of IGFs in vivo. Human IGFBP-3 is a 40-44 kDa glycoprotein that is the most abundant IGFBP in serum and milk. It is produced by non-parenchymal hepatic cells and circulates in serum, binding IGF-I or IGF-II in conjunction with an acid labile subunit (ALS) to form a (1:1:1) 150 kDa circulating complex at a serum concentration of about 100 nM. Free IGF-I has a half-life of ca.10 min in serum. This can be increased to ca.25 min if bound to IGFBP-3 and to ca.15 h if complexed with IGFBP-3 and ALS.

43 - 45 kDa

Characteristic doublet of glycoforms detected by Western ligand blot using mono-biotinyl IGF-II as probe.