Cerebrospinal IGF Binding Proteins : Isolation and Characterization
In biological fluids, IGFs (insulin-like growth factors I and II) are associated with specific, high-affinity (≈ 1010 M-1) binding proteins (BPs) which control both their bioavailability and their action at target cell level (Review in 1). Research done in our laboratory has shown that the BPs are molecularly and functionally heterogenous. Using Western ligand blotting, we have identified five molecular forms in man, of 41.5, 38.5, 34, 30 and 24 kDa. The proportions of these forms vary in different biological fluids and culture media and their regulation and affinities for IGF-I and IGF-II are different (2–6).
KeywordsAmniotic Fluid Human Amniotic Fluid Selective Affinity Target Cell Level Western Ligand Blot Analysis
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