A radioimmunoassay for human epidermal growth factor receptor

摘要: Abstract The development of a radioimmunoassay (RIA) for the human epidermal growth factor receptor solubilized with nonionic detergents which employs iodinated (125I-EGF) as specific ligand is described. A monoclonal antibody (R1) that binds specifically to EGF receptors [Waterfield, M. D., et al. (1982) J. Cell Biochem.20, 149–161] was used separate saturated 125I-EGF from free by absorption protein A-Sepharose, and bound radioactivity determined. RIA linear when increasing amounts membrane were added and, compared standard polyethylene glycol assay, more reproducible. In addition, background nonspecific binding obtained in presence hundred-fold excess unlabeled less RIA. Substitution normal mouse serum gave very low avoided use large assay. Two major classes sites observed preparations cervical carcinoma cell line A431 or placental tissue. These present approximately equal amounts, apparent dissociation constants 4 × 10−10 10−9 m . Upon solubilization detergent Triton X-100, only one class detected both cases, constant 3 10−8 can be monitor purification quantitation number affinity various types.