Immunodetection of the ligand-activated receptor for epidermal growth factor

Growth Factors. 1991;4(4):305-16. doi: 10.3109/08977199109043916.

Abstract

Many receptors for cellular growth factors are known to be protein tyrosine kinases which become activated upon ligand binding at their extracellular domain. We describe here a method to detect the activation state of Epidermal Growth Factor receptor (EGFr) with a monoclonal antibody (mAb74). This antibody was found to preferentially recognize the ligand-activated EGFr as detected by immunoprecipitation, Western blotting and immunocytochemical techniques. mAb74 did not recognize other tyrosine-phosphorylated proteins and was not inhibited by phosphotyrosine, suggesting that it is recognizing an epitope specific for the ligand-activated EGF receptor. The reactivity of mAb74 towards EGFr was closely correlated with the EGF-dependent tyrosine phosphorylation of endogenous substrates. This antibody allows one to detect the activated EGF receptor in vitro or in vivo even in a complex mixture of other tyrosine kinases and substrates.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Antibodies, Monoclonal
  • Blotting, Western
  • Cell Line
  • Epidermal Growth Factor / pharmacology
  • Epitopes
  • ErbB Receptors / immunology
  • ErbB Receptors / metabolism*
  • Fluorescent Antibody Technique
  • Humans
  • Phosphorylation
  • Phosphotyrosine
  • Precipitin Tests
  • Protein-Tyrosine Kinases / metabolism
  • Tyrosine / analogs & derivatives
  • Tyrosine / metabolism

Substances

  • Antibodies, Monoclonal
  • Epitopes
  • Phosphotyrosine
  • Tyrosine
  • Epidermal Growth Factor
  • ErbB Receptors
  • Protein-Tyrosine Kinases