High affinity interleukin-6 receptor is a hexameric complex consisting of two molecules each of interleukin-6, interleukin-6 receptor, and gp-130 Academic Article uri icon

abstract

  • The high affinity human interleukin-6 (IL-6) receptor complex consists of IL-6 and two membrane-associated receptor components, the IL-6 receptor (alpha-subunit) and the high affinity converter and signal transducing molecule, gp-130 (beta-subunit). Recombinant IL-6 and the extracellular ("soluble") components of the IL-6 receptor (sIL-6R) and gp-130 (sgp-130) have been prepared in order to investigate the stoichiometry and binding of these components in the low affinity (IL-6.sIL-6R) and high affinity (IL-6.sIL-6R.sgp-130) IL-6 receptor complexes. Using a combination of size-exclusion chromatography and analytical ultracentrifugation analysis, in the low affinity receptor complex, IL-6 was shown to bind sIL-6R in a stoichiometric ratio of 1:1, whereas the high affinity ternary complex is hexameric consisting of two molecules each of IL-6, sIL-6R, and sgp-130. This is the first direct demonstration of a higher order arrangement for receptor cytokine interactions that exhibit both high and low affinity complexes.

authors

  • Ward, LD
  • Howlett, GJ
  • Discolo, G
  • Yasukawa, K
  • Hammacher, A
  • Moritz, RL
  • Simpson, RJ

publication date

  • September 16, 1994