title: An antibody with a variable-region coiled-coil "knob" domain.
abstract: The X-ray crystal structure of a bovine antibody (BLV1H12) revealed a unique structure in its ultralong heavy chain complementarity determining region 3 (CDR3H) that folds into a solvent-exposed β-strand "stalk" fused to a disulfide crosslinked "knob" domain. We have substituted an antiparallel heterodimeric coiled-coil motif for the β-strand stalk in this antibody. The resulting antibody (Ab-coil) expresses in mammalian cells and has a stability similar to that of the parent bovine antibody. MS analysis of H-D exchange supports the coiled-coil structure of the substituted peptides. Substitution of the knob-domain of Ab-coil with bovine granulocyte colony-stimulating factor (bGCSF) results in a stably expressed chimeric antibody, which proliferates mouse NFS-60 cells with a potency comparable to that of bGCSF. This work demonstrates the utility of this novel coiled-coil CDR3 motif as a means for generating stable, potent antibody fusion proteins with useful pharmacological properties.
authors.affiliation: Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037 (USA); Present address: California Institute for Biomedical Research (Calibr), 11119 N. Torrey Pines Road, La Jolla, CA 92037 (USA).
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Devrishi
authors.initials: D
authors.lastname: Goswami
authors.forename: Danling
authors.initials: D
authors.lastname: Wang
authors.forename: Tsung-Shing Andrew
authors.initials: TS
authors.lastname: Wang
authors.forename: Shiladitya
authors.initials: S
authors.lastname: Sen
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Magliery
authors.forename: Patrick R
authors.initials: PR
authors.lastname: Griffin
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.forename: Peter G
authors.initials: PG
authors.lastname: Schultz
mesh_terms: D000818:Animals; D002417:Cattle; D049109:Cell Proliferation; D002942:Circular Dichroism; D051379:Mice; D008958:Models, Molecular; D010455:Peptides / Q000737:chemistry*; D015202:Protein Engineering; D017433:Protein Structure, Secondary
chemical_list: D010455:Peptides
keywords: CDR; antibodies; coiled coil; polypeptide; protein engineering