The soluble interleukin 6 receptor: mechanisms of production and implications in disease

FASEB J. 2001 Jan;15(1):43-58. doi: 10.1096/fj.99-1003rev.


Interleukin 6 (IL-6) performs a prominent role during disease and has been described as both a pro- and anti-inflammatory cytokine. A key feature in the regulation of IL-6 responses has been the identification of a soluble interleukin 6 receptor (sIL-6R), which forms a ligand-receptor complex with IL-6 that is capable of stimulating a variety of cellular responses including proliferation, differentiation and activation of inflammatory processes. Elevated sIL-6R levels have been documented in numerous clinical conditions indicating that its production is coordinated as part of a disease response. Thus, sIL-6R has the potential to regulate both local and systemic IL-6-mediated events. This review will outline the central role of sIL-6R in the coordination of IL-6 responses. Details relating to the mechanisms of sIL-6R production will be provided, while the potential significance of sIL-6R during the development of clinical conditions will be emphasized. We want to convey, therefore, that when thinking about the inflammatory capability of IL-6, it is essential to consider not only the action of IL-6 itself, but also the effect sIL-6R may have on cellular processes.

Publication types

  • Review

MeSH terms

  • Alternative Splicing
  • Amino Acid Sequence
  • Animals
  • Arthritis / metabolism
  • Arthritis / pathology
  • Base Sequence
  • Cell Differentiation
  • Cell Division
  • Crohn Disease / metabolism
  • Crohn Disease / pathology
  • Disease*
  • Humans
  • Interleukin-6 / physiology
  • Molecular Sequence Data
  • Multiple Myeloma / metabolism
  • Multiple Myeloma / pathology
  • Protein Isoforms / antagonists & inhibitors
  • Protein Isoforms / biosynthesis
  • Protein Isoforms / chemistry
  • Protein Isoforms / metabolism
  • Receptors, Interleukin-6 / antagonists & inhibitors
  • Receptors, Interleukin-6 / biosynthesis*
  • Receptors, Interleukin-6 / chemistry
  • Receptors, Interleukin-6 / metabolism*
  • Signal Transduction
  • Solubility


  • Interleukin-6
  • Protein Isoforms
  • Receptors, Interleukin-6