Functional epitope mapping of human interleukin-1 beta by surface plasmon resonance

Eur Cytokine Netw. 1997 Jun;8(2):161-71.

Abstract

A panel of monoclonal antibodies to human IL-1 beta has been used to probe its conformational and functional characteristics. Real time antibody-protein interaction was assessed by surface plasmon resonance with a BIAcore apparatus, in order to determine the kinetic and thermodynamic parameters of the interaction and to map the recognition sites of the antibodies on the IL-1 beta surface. Topological analysis was thus compared to the inhibitory capacity of antibodies for IL-1 beta bioactivity and binding to the activating receptor IL-1RI. This functional mapping analysis allows the following hypothesis. At least two discrete areas of IL-1 beta, located within the sequences 133-147 and 177-186 (as defined by mAbs MhC1 and BRhD2, respectively), are apparently involved in IL-1RI-independent agonist activity, and thus possibly take part in the interaction with the receptor accessory protein IL-1RAcP. Another area in the 133-147 sequence (defined by mAb BRhC3) is involved in agonist binding to its receptor CDw121a (IL-1RI), whereas a site recognized by mAb BRhG5 within the sequence 218-243 is selectively responsible for non-agonist binding to the activating receptor. The loop between the 4th and the 5th beta-strand, at the open end of the IL-1 beta-barrel structure, may possibly take part in both non-agonist binding to IL-1RI and in the interaction with IL-1RAcP.

MeSH terms

  • Amino Acid Sequence
  • Antibodies, Monoclonal
  • Antigen-Antibody Reactions
  • Binding Sites
  • Biosensing Techniques
  • Epitope Mapping / methods*
  • Epitopes / chemistry*
  • Epitopes / genetics
  • Epitopes / metabolism
  • Humans
  • In Vitro Techniques
  • Interleukin-1 / chemistry
  • Interleukin-1 / genetics
  • Interleukin-1 / immunology*
  • Interleukin-1 Receptor Accessory Protein
  • Kinetics
  • Models, Molecular
  • Protein Conformation
  • Proteins / chemistry
  • Proteins / metabolism
  • Receptors, Interleukin-1 / chemistry
  • Receptors, Interleukin-1 / metabolism
  • Thermodynamics

Substances

  • Antibodies, Monoclonal
  • Epitopes
  • IL1RAP protein, human
  • Interleukin-1
  • Interleukin-1 Receptor Accessory Protein
  • Proteins
  • Receptors, Interleukin-1