Identification and characterization of tumor antigens by using antibody phage display and intrabody strategies.
Journal: 2007/July - Molecular Immunology
ISSN: 0161-5890
Abstract:
To generate a panel of antibodies binding human breast cancers, a human single chain Fv phage display library was selected for rapid internalization into the SK-BR-3 breast cancer cell line. Thirteen unique antibodies were identified within the 55 cell binding antibodies studied, all of them showing specific staining of tumor cells compare to normal epithelial cells. Two of the antibodies bound the ErbB2 oncogene while 6 bound the tumor marker transferrin receptor (TfR). By developing a scFv immunoprecipitation method, we were able to use LC-MS/MS to identify the antigen bound by one of the antibodies (3GA5) as FPRP (prostaglandin F2alpha receptor-regulatory protein)/EWI-F/CD9P-1 (CD9 partner 1) an Ig superfamily member that has been described to interact directly with CD9 and CD81 tetraspanins and to be overexpressed in adherent cancer cell lines. Although the 3GA5 scFv had no direct anti-proliferative effect, intracellular expression of the scFv was able to knockdown CD9P-1 expression and could be used to further define the role of the tetraspanin system in proliferation and metastasis. Moreover, the 3GA5 scFv was rapidly internalized into breast tumor cells and could have potential for the targeted delivery of cytotoxic agents to breast cancers. This study is the proof of principle that the direct selection of phage antibody libraries on tumor cells can effectively lead to the identification and functional characterization of relevant tumor markers.
Relations:
Content
Citations
(16)
References
(53)
Grants
(46)
Chemicals
(6)
Organisms
(4)
Processes
(8)
Anatomy
(2)
Similar articles
Articles by the same authors
Discussion board
Mol Immunol 44(15): 3777-3788

Identification and characterization of tumor antigens by using antibody phage display and intrabody strategies

+2 authors
Laboratoire de Biotechnologie et Pharmacologie Génétique Appliquée (LBPA), UMR CNRS 8113, 61 avenue du Président Wilson, 94235 Cachan Cedex, FRANCE
Departments of Anesthesia and Pharmaceutical Chemistry, University of California, San Francisco, Rm. 3C-38, San Francisco General Hospital, 1001 Potrero Avenue, San Francisco, CA, 94110, USA
Departments of Developmental & Cell Biology and Physiology & Biophysics. University of California, Irvine, Irvine, CA 92697-4560
Hermes Biosciences, 61 Airport Blvd., Suite D, South San Francisco, CA, 94080, USA
Corresponding author: Marie-Alix Poul is to be contacted, E-mail address: rf.nahcac-sne.apbl@luop, Fax 33 (0)1 47 40 76 84
Contributed equally to this work
Publisher's Disclaimer

Abstract

To generate a panel of antibodies binding human breast cancers, a human single chain Fv phage display library was selected for rapid internalization into the SK-BR-3 breast cancer cell line. Thirteen unique antibodies were identified within the 55 cell binding antibodies studied, all of them showing specific staining of tumor cells compare to normal epithelial cells. Two of the antibodies bound the ErbB2 oncogene while 6 bound the tumor marker transferrin receptor (TfR). By developing a scFv immunoprecipitation method, we were able to use LC-MS/MS to identify the antigen bound by one of the antibodies (3GA5) as FPRP (prostaglandin F2alpha receptor-regulatory protein)/EWI-F/CD9P-1 (CD9 partner 1) an Ig superfamily member that has been described to interact directly with CD9 and CD81 tetraspanins and to be overexpressed in adherent cancer cell lines. Although the 3GA5 scFv had no direct anti-proliferative effect, intracellular expression of the scFv was able to knockdown CD9P-1 expression and could be used to further define the role of the tetraspanin system in proliferation and metastasis. Moreover, the 3GA5 scFv was rapidly internalized into breast tumor cells and could have potential for the targeted delivery of cytotoxic agents to breast cancers. This study is the proof of principle that the direct selection of phage antibody libraries on tumor cells can effectively lead to the identification and functional characterization of relevant tumor markers.

Keywords: phage display, scFv, intrabody, tumor marker, internalization, CD9P-1, transferrin receptor
Abstract

Footnotes

Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Footnotes
Collaboration tool especially designed for Life Science professionals.Drag-and-drop any entity to your messages.