title: A high-affinity CDR-grafted antibody against influenza A H5N1 viruses recognizes a conserved epitope of H5 hemagglutinin.
abstract: Highly pathogenic avian influenza (HPAI) H5N1 virus infection is still a potential threat to public health worldwide. While vaccines and antiviral drugs are currently under development, neutralizing antibodies could offer an alternative strategy to prevent and treat H5N1 virus infection. In the present study, we had developed a humanized antibody against H5N1 viruses from mouse-derived hybridoma in order to minimize its immunogenicity for potential clinical application. The humanized antibody hH5M9 was generated by transferring the mouse complementarity determining region (CDR) residues together with four key framework region (FR) residues onto the FR of the human antibody. This humanized antibody exhibited high affinity and specificity comparable to the parental mouse or chimeric counterpart with broad and strong neutralization activity against all H5N1 clades and subclades except for Egypt clades investigated. Furthermore, through epitope mapping we identified a linear epitope on the top region of hemagglutinin (HA) that was H5N1 specific and conserved. Our results for the first time reported a humanized antibody against H5N1 viruses by CDR grafting method. With the expected lower immunogenicity, this humanized antibody was expected to be more efficacious than murine or human-mouse chimeric antibodies for future application in humans.
authors.affiliation: School of Life Science and Technology, Tongji University, Shanghai, China ; Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China.
authors.forename: Feifei
authors.initials: F
authors.lastname: Xiong
authors.affiliation: Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China.
authors.forename: Liliang
authors.initials: L
authors.lastname: Xia
authors.affiliation: Shanghai Center for Systems Biomedicine, Shanghai Jiaotong University, Shanghai, China.
authors.forename: Jingfang
authors.initials: J
authors.lastname: Wang
authors.affiliation: Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China.
authors.forename: Biao
authors.initials: B
authors.lastname: Wu
authors.affiliation: Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China.
authors.forename: Dengyu
authors.initials: D
authors.lastname: Wang
authors.affiliation: Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China.
authors.forename: Longfang
authors.initials: L
authors.lastname: Yuan
authors.affiliation: Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China.
authors.forename: Yating
authors.initials: Y
authors.lastname: Cheng
authors.affiliation: Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China.
authors.forename: Hongying
authors.initials: H
authors.lastname: Zhu
authors.affiliation: Central Laboratory, Zhujiang Hospital, The Southern Medical University, Guangzhou, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Che
authors.affiliation: School of Life Science and Technology, Tongji University, Shanghai, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China.
authors.forename: Guoping
authors.initials: G
authors.lastname: Zhao
authors.affiliation: Shanghai-MOST Key Laboratory of Health and Disease Genomics, Chinese National Human Genome Center at Shanghai, Shanghai, China ; Shanghai Institute of Immunology, Shanghai Jiaotong University School of Medicine, Shanghai, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D061067:Antibodies, Monoclonal, Humanized / Q000737:chemistry / Q000276:immunology*; D057134:Antibodies, Neutralizing / Q000737:chemistry / Q000276:immunology; D022801:Complementarity Determining Regions / Q000276:immunology*; D017124:Conserved Sequence; D018604:Epitope Mapping; D000939:Epitopes / Q000276:immunology*; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000276:immunology*; D006801:Humans; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology*; D051379:Mice; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D057134:Antibodies, Neutralizing; D022801:Complementarity Determining Regions; D000939:Epitopes; D019267:Hemagglutinin Glycoproteins, Influenza Virus