Separation of the molecular forms of the insulin-like growth factor (IGF)—Binding proteins by affinity chromatography

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Analytical technologies in the biomedical and life sciences, 2009-03, Vol.877 (8), p.743-746
• Main Authors: Nedić, Olgica, Masnikosa, Romana
• Format: Article
• Language: English
• Subjects: Adult; Affinity chromatography; Analysis; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Chromatography, Affinity - methods; Female; Fundamental and applied biological sciences. Psychology; General pharmacology; Humans; IGFBP-1; IGFBP-2; IGFBP-3; Insulin-Like Growth Factor Binding Proteins - blood; Insulin-Like Growth Factor Binding Proteins - chemistry; Insulin-Like Growth Factor Binding Proteins - isolation & purification; Male; Medical sciences; Middle Aged; Molecular forms; Pharmacology. Drug treatments; Placenta - chemistry; Protein Binding
• ISSN: 1570-0232; 1873-376X
• DOI: 10.1016/j.jchromb.2009.02.011

Association of IGFBP-1, IGFBP-2 and IGFBP-3 with other proteins in human serum and placental cell membranes was investigated using affinity chromatography matrix with immobilized antibodies. Circulating IGFBP-1 was found to be predominantly bound to α 2-macroglobulin and not in the binary complex with its ligand, IGFBP-2 complexes and/or polymers were detected, which was not acknowledged before, and IGFBP-3 molecular forms were differentiated into those that form binary/ternary complexes and those that form stable associations with other serum proteins. As for placental membranes, both IGFBP-1 dimers and high molecular mass IGFBP-1 associations, most probably with α 2-macroglobulin, were recognized and resolved.