Non-linear antigenic regions in epidermal growth factor (EGF) and transforming growth factor α (TGFα) studied by EGF–TGFα chimaeras

• Published in: Biochemical journal 2000-07, Vol.349 (1), p.267-274
• Main Authors: VAN DE POLL, Monique L. M., VAN ROTTERDAM, Walter, GADELLAA, Mireille M., STORTELERS, Catelijne, VAN VUGT, Marianne J. H., VAN ZOELEN, Everardus J. J.
• Format: Article
• Language: English
• ISSN: 0264-6021; 1470-8728
• DOI: 10.1042/bj3490267

With the help of 16 chimaeras between human epidermal growth factor (hEGF) and human transforming growth factor α (hTGFα), a detailed analysis was performed on the epitope recognized by two polyclonal antibodies raised against hEGF, and one polyclonal antibody raised against hTGFα. All three antibodies recognized essentially the same antigenic site, a non-linear and conformation-dependent sequence that is located near the second and fourth disulphide-bonded cysteines and that includes the start of the B-loop β-sheet. The epitope recognized by the anti-hEGF antibodies was further characterized using 8 chimaeras between hEGF and an EGF-repeat from Drosophila Notch and was found to include Met21, Ala30 and Asn32. All three polyclonal antibodies were able to neutralize the biological activity of the respective growth factor when tested on 32D murine haematopoietic progenitor cells transfected with ErbB-1, indicating that the receptor binding domain is shielded upon binding of the antibody.