Monomer-dimer equilibria of interleukin-8 and neutrophil-activating peptide 2. Evidence for IL-8 binding as a dimer and oligomer to IL-8 receptor B

J Leukoc Biol. 1994 Jun;55(6):763-70. doi: 10.1002/jlb.55.6.763.


By chemical cross-linking experiments we show that at physiologically relevant concentrations IL-8 and NAP-2 monomers are in an equilibrium with dimers and even oligomers (KD approximately 300-800 nM). Oligomerization seems to be more prevalent for IL-8 than for NAP-2. The form in which IL-8 and NAP-2 bind to their specific receptors was analyzed in binding experiments with COS-1 cells expressing IL-8 receptor A or B in recombinant forms. Both receptors were cloned from the human myeloid leukemic cell line AML-193. Type A receptor had high affinity for IL-8 (KD approximately 4 nM) and low affinity for NAP-2 (KD > or = 700 nM), whereas the type B receptor was of equally high affinity (KD approximately 2 nM) for both IL-8 and NAP-2. However, IL-8 receptor B could bind specifically three to four times more IL-8 than NAP-2, and NAP-2 was a weak competitor for IL-8 binding to the same receptor. In addition, IL-8, but not NAP-2, could be cross-linked to dimers when bound to IL-8 receptor B. We suggest from these findings that IL-8, but not NAP-2, binds as a dimer and oligomer to IL-8 receptor.

MeSH terms

  • Animals
  • Cell Line
  • Chlorocebus aethiops
  • Cloning, Molecular
  • Cross-Linking Reagents
  • Electrophoresis, Polyacrylamide Gel
  • Humans
  • Interleukin-8 / isolation & purification
  • Interleukin-8 / metabolism*
  • Iodine Radioisotopes
  • Kinetics
  • Leukemia, Myeloid
  • Macromolecular Substances
  • Peptides / isolation & purification
  • Peptides / metabolism*
  • Receptors, Interleukin / biosynthesis
  • Receptors, Interleukin / metabolism*
  • Receptors, Interleukin-8A
  • Recombinant Proteins / biosynthesis
  • Recombinant Proteins / metabolism
  • Transfection
  • Tumor Cells, Cultured
  • beta-Thromboglobulin


  • Cross-Linking Reagents
  • Interleukin-8
  • Iodine Radioisotopes
  • Macromolecular Substances
  • PPBP protein, human
  • Peptides
  • Receptors, Interleukin
  • Receptors, Interleukin-8A
  • Recombinant Proteins
  • beta-Thromboglobulin
  • connective tissue-activating peptide