title: Selection of an affinity-matured antibody against a defined epitope by phage display of an immune antibody library.
abstract: In a previous study, we generated a murine hepatitis B virus (HBV)-neutralizing monoclonal antibody (mAb), KR127, that binds to an epitope (amino acids 37-45, NSNNPDWDF) of the preS1 antigen. Furthermore, an epitope tag, S1 (NANNPDWDF), was developed for protein tagging. The aim of the present study was to develop a high-affinity antibody to the same preS1 epitope. Mice were immunized with the N-terminal domain of human thrombopoietin fused to the S1 tag (nTPO-S1), and a phage-displayed chimeric Fab library was constructed and screened by panning against nTPO-S1. A high-affinity antibody (3-34) was selected that binds to the preS1 antigen. The IgG molecules of 3-34 showed approximately nine-fold higher affinity (K(D) 1.2 nM) for preS1 compared with KR127 (K(D) 10.4 nM), competed with KR127 for binding to the epitope, and bound to HBV particles. This study provides a simple and efficient way to develop a high-affinity antibody to a defined epitope by phage display of an immune antibody library.
authors.affiliation: Therapeutic Antibody Research Center, Korea Research Institute of Bioscience and Biotechnology, Yuseong, Daejon 305-333, South Korea.
authors.forename: Sang Jick
authors.initials: SJ
authors.lastname: Kim
authors.forename: Myeong Hee
authors.initials: MH
authors.lastname: Jang
authors.forename: Hyun Joo
authors.initials: HJ
authors.lastname: Ahn
authors.forename: Jin Hong
authors.initials: JH
authors.lastname: Kim
authors.forename: Ji Hye
authors.initials: JH
authors.lastname: Lim
authors.forename: Chun Jeih
authors.initials: CJ
authors.lastname: Ryu
authors.forename: Nam-Kyu
authors.initials: NK
authors.lastname: Lim
authors.forename: Keun-Soo
authors.initials: KS
authors.lastname: Kim
authors.forename: Mi-Ju
authors.initials: MJ
authors.lastname: Park
authors.forename: Insoo
authors.initials: I
authors.lastname: Park
authors.forename: Hyo Jeong
authors.initials: HJ
authors.lastname: Hong
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification*; D000915:Antibody Affinity; D000918:Antibody Specificity; D001666:Binding Sites, Antibody; D000939:Epitopes; D006514:Hepatitis B Surface Antigens / Q000276:immunology* / Q000378:metabolism; D006515:Hepatitis B virus / Q000276:immunology* / Q000378:metabolism; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000096:biosynthesis / Q000235:genetics / Q000302:isolation & purification*; D051379:Mice; D008807:Mice, Inbred BALB C; D019151:Peptide Library; D011498:Protein Precursors / Q000276:immunology* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000276:immunology; D013926:Thrombopoietin / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000939:Epitopes; D006514:Hepatitis B Surface Antigens; D007140:Immunoglobulin Fab Fragments; D019151:Peptide Library; D011498:Protein Precursors; D011993:Recombinant Fusion Proteins; C050806:presurface protein 1, hepatitis B surface antigen; D013926:Thrombopoietin