Method for determining cytokine receptor activation by the use of an antibody

摘要

A method for determining cytokine receptor activation, especially growth hormone receptor (GHR) activation, using an antibody capable of discriminating between an activated and an inactive cytokine receptor conformation, especially GHR or growth hormone binding protein (GHBP) conformation. The method comprises contacting the antibody and the cytokine receptor to form a complex, contacting a candidate ligand to the complex, measuring the antibody binding to inactive cytokine receptor and thereby discriminating between an activated and an inactive conformation. It also relates to a method for screening for functionally cytokine agonists and antagonists, especially functionally growth hormone (GH) agonists, among candidate ligands by the use of an antibody specific for activated cytokine receptor conformation. The antibody is directed to the hinge spanning subdomains I and II of the growth hormone receptor extracellular region and is capable of discriminating between an activated and an inactive receptor conformation.