LIGAND-MEDIATED IMMUNOFUNCTIONAL HORMONE BINDING PROTEIN ASSAY METHOD

摘要

A ligand-mediated immunofunctional assay (LIFA) method for detecting thepresence and the concentration of polypeptide hormone binding proteins whichcomprises capturing the binding protein with a solid phase bound firstantibody,saturating the bound hormone binding protein with the ligand polypeptidehormone,and detecting the bound ligand polypeptide hormone with a detectably labeledsecondantibody specific for the ligand polypeptide hormone. In the absence of addedsaturating polypeptide hormone, the LIFA measures the amount of hormonebindingprotein bound to the endogenous ligand polypeptide hormone. A growth hormonebinding protein assay illustrates the method of the present invention. LIFAassayresults indicate that increased binding protein substantially increases growthhormone activity. Methods of use and formulations of growth hormone bindingprotein, growth hormone, insulin-like growth factor-I and insulin-like growthfactor binding protein are disclosed.