title: Epitope mapping of mouse monoclonal antibody EP-5C7 which neutralizes both human E- and P-selectin.
abstract: The epitope of mouse monoclonal antibody (mAb) EP-5C7, which binds to and blocks both human E- and P-selectin, was mapped onto the protein structure of E-selectin. Analyses with E- and L-selectin chimeric proteins and randomly mutagenized E-selectins demonstrated that the EP-5C7 epitope consists of the amino acid residues at positions 21, 22, 23, 119 and 120 of E-selectin. The binding of three neutralizing anti-E-selectin mAb's (E-1E4, H18/7 and CL2), whose epitopes were found to overlap with the E-selectin binding site for carbohydrate ligands, was not affected by the amino acid substitutions at these five positions. Inspection of the three-dimensional structure of E-selectin indicated that the EP-5C7 epitope is located near the junction between the lectin and EGF-like domains. The ligand binding site was distant from the EP-5C7 epitope, suggesting that the amino acid residues in the EP-5C7 epitope play an important role other than ligand binding in selectin-mediated cell adhesion.
authors.affiliation: Protein Design Labs, Inc., Mountain View, California 94043, USA. naoya@pdl.com
authors.forename: N
authors.initials: N
authors.lastname: Tsurushita
authors.forename: H
authors.initials: H
authors.lastname: Fu
authors.forename: J
authors.initials: J
authors.lastname: Melrose
authors.forename: E L
authors.initials: EL
authors.lastname: Berg
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D058846:Antibodies, Monoclonal, Murine-Derived; D001665:Binding Sites; D019040:E-Selectin / Q000235:genetics / Q000276:immunology*; D004815:Epidermal Growth Factor / Q000276:immunology; D018604:Epitope Mapping; D000939:Epitopes / Q000235:genetics / Q000276:immunology; D006801:Humans; D007249:Inflammation / Q000628:therapy; D037102:Lectins / Q000276:immunology; D051379:Mice; D016296:Mutagenesis; D009500:Neutralization Tests; D019007:P-Selectin / Q000276:immunology*; D011993:Recombinant Fusion Proteins / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D019040:E-Selectin; C110220:EP-5C7 monoclonal antibody; D000939:Epitopes; D037102:Lectins; D019007:P-Selectin; D011993:Recombinant Fusion Proteins; D004815:Epidermal Growth Factor