title: Epitope mapping of PR81 anti-MUC1 monoclonal antibody following PEPSCAN and phage display techniques.
abstract: PR81 is an anti-MUC1 monoclonal antibody (MAb) which was generated against human MUC1 mucin that reacted with breast cancerous tissue, MUC1 positive cell line (MCF-7, BT-20, and T-4 7 D), and synthetic peptide, including the tandem repeat sequence of MUC1. Here we characterized the binding properties of PR81 against the tandem repeat of MUC1 by two different epitope mapping techniques, namely, PEPSCAN and phage display. Epitope mapping of PR81 MAb by PEPSCAN revealed a minimal consensus binding sequence, PDTRP, which is found on MUC1 peptide as the most important epitope. Using the phage display peptide library, we identified the motif PD(T/S/G)RP as an epitope and the motif AVGLSPDGSRGV as a mimotope recognized by PR81. Results of these two methods showed that the two residues, arginine and aspartic acid, have important roles in antibody binding and threonine can be substituted by either glycine or serine. These results may be of importance in tailor making antigens used in immunoassay.
authors.affiliation: Tarbiat Modares University, School of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Mohammadi
authors.forename: Mohammad Javad
authors.initials: MJ
authors.lastname: Rasaee
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Rajabibazl
authors.forename: Malihe
authors.initials: M
authors.lastname: Paknejad
authors.forename: Mehrak
authors.initials: M
authors.lastname: Zare
authors.forename: Sara
authors.initials: S
authors.lastname: Mohammadzadeh
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000737:chemistry*; D000918:Antibody Specificity; D001667:Binding, Competitive; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping / Q000379:methods; D006801:Humans; D006825:Hybridomas; D051379:Mice; D008969:Molecular Sequence Data; D018396:Mucin-1 / Q000276:immunology*; D019151:Peptide Library; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment
chemical_list: D000911:Antibodies, Monoclonal; D018396:Mucin-1; D019151:Peptide Library