title: Rational design of CXCR4 specific antibodies with elongated CDRs.
abstract: The bovine antibody (BLV1H12) which has an ultralong heavy chain complementarity determining region 3 (CDRH3) provides a novel scaffold for antibody engineering. By substituting the extended CDRH3 of BLV1H12 with modified CXCR4 binding peptides that adopt a β-hairpin conformation, we generated antibodies specifically targeting the ligand binding pocket of CXCR4 receptor. These engineered antibodies selectively bind to CXCR4 expressing cells with binding affinities in the low nanomolar range. In addition, they inhibit SDF-1-dependent signal transduction and cell migration in a transwell assay. Finally, we also demonstrate that a similar strategy can be applied to other CDRs and show that a CDRH2-peptide fusion binds CXCR4 with a K(d) of 0.9 nM. This work illustrates the versatility of scaffold-based antibody engineering and could greatly expand the antibody functional repertoire in the future.
authors.affiliation: Department of Chemistry and the Skaggs Institute for Chemical Biology, The Scripps Research Institute , La Jolla, California 92037, United States.
authors.forename: Tao
authors.initials: T
authors.lastname: Liu
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Mitchell
authors.initials: M
authors.lastname: Hull
authors.forename: Peter G
authors.initials: PG
authors.lastname: Schultz
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D000918:Antibody Specificity; D002417:Cattle; D002460:Cell Line; D054377:Chemokine CXCL12 / Q000276:immunology; D022801:Complementarity Determining Regions / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D015202:Protein Engineering; D017433:Protein Structure, Secondary; D019718:Receptors, CXCR4 / Q000276:immunology*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000276:immunology
chemical_list: D000906:Antibodies; D054377:Chemokine CXCL12; D022801:Complementarity Determining Regions; D010455:Peptides; D019718:Receptors, CXCR4; D011993:Recombinant Fusion Proteins