title: Engineering fully human monoclonal antibodies from murine variable regions.
abstract: Fully human monoclonal antibodies (mAbs) derived from transgenic mice or human antibody libraries are the current state of the art for reducing the immunogenicity risk of antibody drugs. Here, we describe a novel method for generating fully human mAbs from nonhuman variable regions using information from the human germline repertoire. Central to our strategy is the rational engineering of residues within and proximal to CDRs and the V(H)/V(L) interface by iteratively exploring substitutions to the closest human germline sequences using semi-automated computational methods. Starting from the parent murine variable regions of three currently marketed mAbs targeting CD25, vascular endothelial growth factor, and tumor necrosis factor alpha, we have generated fully human antibodies with 59, 46, and 45 substitutions, respectively, compared to the parent murine sequences. A large number of these substitutions were in the CDRs, which are typically avoided in humanization methods. Antigen affinities of the fully human variants were comparable to the chimeric mAbs in each case. Furthermore, in vitro functional characterization indicated that all retain potency of the chimeric mAbs and have comparable activity to their respective marketed drugs daclizumab, bevacizumab, and infliximab. Based on local and global sequence identity, the sequences of our engineered mAbs are indistinguishable from those of fully human mAbs isolated from transgenic mice or human antibody libraries. This work establishes a simple rational engineering methodology for generating fully human antibody therapeutics from murine mAbs produced from standard hybridoma technology.
authors.affiliation: Xencor, Inc, 111 West Lemon Avenue, Monrovia, CA 91016, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Bernett
authors.forename: Sher
authors.initials: S
authors.lastname: Karki
authors.forename: Gregory L
authors.initials: GL
authors.lastname: Moore
authors.forename: Irene W L
authors.initials: IW
authors.lastname: Leung
authors.forename: Hsing
authors.initials: H
authors.lastname: Chen
authors.forename: Erik
authors.initials: E
authors.lastname: Pong
authors.forename: Duc-Hanh T
authors.initials: DH
authors.lastname: Nguyen
authors.forename: Jonathan
authors.initials: J
authors.lastname: Jacinto
authors.forename: Jonathan
authors.initials: J
authors.lastname: Zalevsky
authors.forename: Umesh S
authors.initials: US
authors.lastname: Muchhal
authors.forename: John R
authors.initials: JR
authors.lastname: Desjarlais
authors.forename: Greg A
authors.initials: GA
authors.lastname: Lazar
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D000911:Antibodies, Monoclonal / Q000235:genetics*; D002478:Cells, Cultured; D022801:Complementarity Determining Regions / Q000235:genetics; D006801:Humans; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D066298:In Vitro Techniques; D053645:Interleukin-2 Receptor alpha Subunit / Q000037:antagonists & inhibitors; D051379:Mice; D008822:Mice, Transgenic; D008969:Molecular Sequence Data; D019151:Peptide Library; D015202:Protein Engineering / Q000379:methods*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D013601:T-Lymphocytes / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors; D042461:Vascular Endothelial Growth Factor A / Q000037:antagonists & inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D022801:Complementarity Determining Regions; C508017:IL2RA protein, human; D007135:Immunoglobulin Variable Region; D053645:Interleukin-2 Receptor alpha Subunit; D019151:Peptide Library; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A