Table of Contents
International Journal of Proteomics
Volume 2012, Article ID 247059, 5 pages
Research Article

A Miniaturized Ligand Binding Assay for EGFR

1NMI Natural and Medical Sciences Institute at the University of Tübingen, Markwiesenstraße 55, 72770 Reutlingen, Germany
2Science for Life Laboratory Stockholm, School of Biotechnology, KTH Royal Institute of Technology, P.O. Box 1031, 171 21 Solna, Sweden
3Molecular Oncology Group, Department of Obstetrics and Gynecology, Medical University of Vienna, Währinger Gürtel 18-20, 5Q, 1090 Vienna, Austria

Received 9 September 2011; Revised 17 January 2012; Accepted 18 January 2012

Academic Editor: Ákos Végvári

Copyright © 2012 Jochen M. Schwenk et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


In order to study receptor abundance and its function in solutions or in homogenates from clinical specimen, methods such as sandwich or radioimmunoassays are most commonly employed. For the determination of epidermal growth factor receptor (EGFR), we describe the development of a miniaturized bead-based ligand binding assay using its ligand EGF as immobilized capture reagent. This assay was used to analyze lysates from cell lines, and the ligand-bound EGFR was detected using an EGFR-specific antibody combined with a fluorescence-based reporter system. In a proof-of concept study with lysates from breast biopsies, the assay allowed to classify breast cancer samples in accordance to clinically the relevant EGFR cut-off level. The study suggests that such a ligand binding receptor assay could become an integral part of protein profiling procedures to provide additional information about receptor functionality in addition to its abundance.