A model system for detection and isolation of a tumor cell surface antigen using antibody phage display.
To establish a screening procedure for tumor cell-surface reactive Fabs, we used a model antigen/antibody system including the epidermal growth factor receptor (EGF-R) and the anti-EGF-R monoclonal antibody 425. The 425 Fab was displayed on the surface of M13 filamentous phage. In a screening assay for 425 phage binding to tumor cell surfaces, biotinylated 425-phage bound specifically to EGF-R-positive A431 epidermoid carcinoma cells and not to K562 non-expressor erythroleukemia cells. With a model library, the sensitivity of phage enrichment by phage binding to cell surfaces was one 425-phage in 20,000 unrelated phages after 4 rounds of panning on A431 cells. In a phage tissue screening assay, 425-phage, but not unrelated phage, bound specifically to melanoma cells expressing EGF-R. Epitope and idiotope specificity of 425-phage was demonstrated in phage competition assays, using as targets A431 cells and anti-idiotypic antibodies to monoclonal antibody 425, respectively. Finally, the EGF-R protein was directly isolated from A431 cell extracts, using biotinylated 425-phage. The data obtained with the 425 model library system demonstrate the usefulness of antibody phage display for the rapid identification and isolation of tumor or other disease-related cell surface antigens.
Pereira
S
S
Wistar Institute, Philadelphia, PA 19104, USA.
Maruyama
H
H
Siegel
D
D
Van Belle
P
P
Elder
D
D
Curtis
P
P
Herlyn
D
D
D000230:Adenocarcinoma / Q000276:immunology / Q000378:metabolism / Q000821:virology; D000888:Antibodies, Anti-Idiotypic / Q000378:metabolism; D000911:Antibodies, Monoclonal / Q000737:chemistry* / Q000378:metabolism; D000951:Antigens, Neoplasm / Q000276:immunology / Q000302:isolation & purification*; D000954:Antigens, Surface / Q000276:immunology / Q000302:isolation & purification*; D017104:Bacteriophage M13 / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D001666:Binding Sites, Antibody; D066246:ErbB Receptors / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000378:metabolism; D008545:Melanoma / Q000378:metabolism / Q000821:virology; D018448:Models, Immunological; D011485:Protein Binding / Q000276:immunology; D014407:Tumor Cells, Cultured
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D007140:Immunoglobulin Fab Fragments; D066246:ErbB Receptors