title: Production of a novel camel single-domain antibody specific for the type III mutant EGFR.
abstract: Camelids have a unique immune system capable of producing single-domain heavy-chain antibodies. The antigen-specific domain of these heavy-chain IgGs (VHH) are the smallest binding units produced by the immune system. In this study, we report the isolation and characterization of several binders against the epidermal growth factor receptor (EGFR) vIII retrieved from immune library of camels (Camelus bactrianus and Camelus dromedarius). The EGFRvIII is a ligand-independent, constitutively active, mutated form of the wild-type EGFR. The expression of EGFRvIII has been demonstrated in a wide range of human malignancies, including gliomas, and breast, prostate, ovarian and lung cancer. Camels were immunized with a synthetic peptide corresponding to a mutated sequence and tissue homogenates. Single-domain antibodies (VHH) were directly selected by panning a phage display library on successively decreasing amounts of synthetic peptide immobilized on magnetic beads. The anti-EGFRvIII camel single-domain antibodies selectively bound to the EGFRvIII peptide and reacted specifically with the immunoaffinity-purified antigen from a non-small cell lung cancer patient. These antibodies with affinities in the nanomolar range recognized the EGFRvIII peptide and affinity-purified mutated receptor. We concluded that using the phage display technique, antigen-specific VHH antibody fragments are readily accessible from the camelids. These antibodies may be good candidates for tumor-diagnostic and therapeutic applications.
authors.affiliation: Department of Biochemistry, School of Medical Sciences, Tarbiat Modarres University, Tehran, Iran.
authors.forename: K
authors.initials: K
authors.lastname: Omidfar
authors.forename: M J
authors.initials: MJ
authors.lastname: Rasaee
authors.forename: H
authors.initials: H
authors.lastname: Modjtahedi
authors.forename: M
authors.initials: M
authors.lastname: Forouzandeh
authors.forename: M
authors.initials: M
authors.lastname: Taghikhani
authors.forename: N
authors.initials: N
authors.lastname: Golmakani
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis*; D000917:Antibody Formation; D014408:Biomarkers, Tumor / Q000032:analysis; D001943:Breast Neoplasms / Q000276:immunology; D002162:Camelus / Q000276:immunology; D002289:Carcinoma, Non-Small-Cell Lung / Q000276:immunology; D066246:ErbB Receptors / Q000235:genetics* / Q000276:immunology*; D005260:Female; D006258:Head and Neck Neoplasms / Q000276:immunology; D006801:Humans; D007114:Immunization / Q000662:veterinary; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G / Q000276:immunology*; D007143:Immunoglobulin Heavy Chains; D008175:Lung Neoplasms / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology; D019151:Peptide Library; D014407:Tumor Cells, Cultured; D014846:Vulvar Neoplasms / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D007128:Immunoglobulin Fragments; D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains; D019151:Peptide Library; C410723:epidermal growth factor receptor VIII; D066246:ErbB Receptors