Single variable domain-IgG fusion. A novel recombinant approach to Fc domain-containing bispecific antibodies

J Biol Chem. 2006 Apr 21;281(16):10706-14. doi: 10.1074/jbc.M513415200. Epub 2006 Feb 15.

Abstract

Both laboratory and early clinical studies to date have demonstrated that bispecific antibodies (BsAb) may have potentially significant application in cancer therapy. The clinical development of BsAb as therapeutics has been hampered, however, by the difficulty in preparing the materials in sufficient quantity and quality by traditional methods. In recent years, a variety of recombinant methods has been developed for efficient production of BsAb, both as antibody fragments and as full-length IgG-like molecules. Here we describe a novel recombinant approach for the production of an Fc domain-containing, IgG-like tetravalent BsAb, with two antigen-binding sites to each of its target antigens, by genetically fusing a single variable domain antibody to the N terminus of the light chain of a functional IgG antibody of different specificity. A model BsAb was constructed using a single variable domain antibody to mouse platelet-derived growth factor receptor alpha and a conventional IgG antibody to mouse vascular endothelial growth factor receptor 2. The BsAb was expressed in mammalian cells and purified to homogeneity by one-step protein A affinity chromatography. Furthermore, the BsAb retains the antigen binding specificity and the receptor neutralizing activity of both of its parent antibodies. This design and expression of Fc domain-containing, IgG-like BsAb should be applicable to the construction of similar BsAb from antibodies recognizing any pair of antigens.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antibodies, Bispecific / chemistry*
  • Antibody Specificity
  • Binding Sites
  • Chromatography
  • Chromatography, Affinity
  • Cross-Linking Reagents / pharmacology
  • Dose-Response Relationship, Drug
  • Dose-Response Relationship, Immunologic
  • Electrophoresis, Polyacrylamide Gel
  • Enzyme-Linked Immunosorbent Assay
  • Escherichia coli / metabolism
  • Immunoglobulin Fragments
  • Immunoglobulin G / chemistry*
  • Immunologic Techniques
  • Inhibitory Concentration 50
  • Kinetics
  • Mice
  • Molecular Sequence Data
  • Neoplasms / immunology
  • Neoplasms / metabolism
  • Peptide Library
  • Phosphorylation
  • Platelet-Derived Growth Factor / metabolism
  • Protein Binding
  • Protein Structure, Tertiary
  • Recombinant Fusion Proteins / chemistry*
  • Sequence Homology, Amino Acid
  • Vascular Endothelial Growth Factor A / metabolism
  • Vascular Endothelial Growth Factor Receptor-2 / metabolism

Substances

  • Antibodies, Bispecific
  • Cross-Linking Reagents
  • Immunoglobulin Fragments
  • Immunoglobulin G
  • Peptide Library
  • Platelet-Derived Growth Factor
  • Recombinant Fusion Proteins
  • Vascular Endothelial Growth Factor A
  • platelet-derived growth factor A
  • Vascular Endothelial Growth Factor Receptor-2