Isolation of a novel cytokine from human fibroblasts that specifically inhibits osteoclastogenesis

Biochem Biophys Res Commun. 1997 May 8;234(1):137-42. doi: 10.1006/bbrc.1997.6603.


A factor which inhibits osteoclast-like cell formation was found in the conditioned medium of human embryonic lung fibroblasts, IMR-90. The factor, termed osteoclastogenesis inhibitory factor, OCIF, was purified to homogeneity. OCIF is a heparin-binding basic glycoprotein and has been isolated as a monomer with an apparent molecular weight (Mr) of 60,000 and a homodimer with a Mr of 120,000. The N-terminus of OCIF is blocked and the determination of internal amino acid sequences revealed that OCIF has no homology to known proteins. OCIF inhibited in a dose-dependent manner osteoclastogenesis elicited through three distinct signaling pathways stimulated by 1 alpha,25-dihydroxy vitamin D3, parathyroid hormone, and interleukin-11, respectively, in a dose range of 1 to 40 ng/ml (IC50 = 4 to 6 ng/ml). OCIF neither inhibits bone resorption by mature osteoclasts nor exerts any other biological activities. These data strongly suggest that OCIF is a novel cytokine which specifically inhibits osteoclastogenesis.

MeSH terms

  • Acid Phosphatase / metabolism
  • Animals
  • Calcitriol / pharmacology
  • Cell Line
  • Chromatography, Affinity
  • Chromatography, High Pressure Liquid
  • Chromatography, Ion Exchange
  • Culture Media, Conditioned
  • Cytokines / chemistry
  • Cytokines / isolation & purification*
  • Cytokines / pharmacology*
  • Electrophoresis, Polyacrylamide Gel
  • Fibroblasts / chemistry*
  • Humans
  • Mice
  • Molecular Weight
  • Osteoclasts / cytology*
  • Osteoclasts / drug effects
  • Parathyroid Hormone / pharmacology
  • Serine Endopeptidases / metabolism


  • Culture Media, Conditioned
  • Cytokines
  • Parathyroid Hormone
  • Acid Phosphatase
  • Serine Endopeptidases
  • lysyl endopeptidase
  • Calcitriol