IL-6 plays an essential role in neutrophilia under inflammation

Cytokine. 2011 Apr;54(1):92-9. doi: 10.1016/j.cyto.2011.01.007. Epub 2011 Feb 2.


In the present study, we explored the involvement of interleukin-6 (IL-6) in neutrophilia under inflammatory conditions. The neutrophil count in the peripheral blood was high in arthritic monkeys, and anti-IL-6 receptor antibody reduced neutrophil counts to normal levels. IL-6 injection into normal monkeys significantly increased neutrophil counts in the blood 3h after injection. The expression of cluster of differentiation (CD) 162 on circulating neutrophils was reduced by IL-6 injection. IL-6 treatment in vitro did not affect CD162 expression on neutrophils from human blood. In IL-6-treated monkeys, IL-8 and granulocyte-macrophage colony-stimulating factor (GM-CSF) levels in plasma were clearly elevated. IL-8 and GM-CSF treatment in vitro reduced cell-surface CD162 expression on human neutrophils, and moreover, increased soluble CD162 expression in the cell supernatant. The addition of IL-6 into human whole peripheral blood induced IL-8 production and reduced CD162 expression on neutrophils. Furthermore, IL-8 and GM-CSF augmented mRNA expression of a disintegrin and metalloprotease like domain 10 (ADAM10) in neutrophils. Knock-down of ADAM10 by siRNA in neutrophil-like HL-60 cells partially reversed the expression of CD162 reduced by GM-CSF and IL-8 on HL-60 cells. In conclusion, IL-6 induced neutrophilia and reduced CD162 expression on neutrophils in inflammation.

MeSH terms

  • ADAM Proteins / blood
  • ADAM10 Protein
  • Amyloid Precursor Protein Secretases / blood
  • Animals
  • Arthritis, Experimental / blood
  • Flow Cytometry / methods
  • Granulocyte-Macrophage Colony-Stimulating Factor / blood
  • HL-60 Cells
  • Humans
  • Inflammation / blood*
  • Interleukin-6 / blood*
  • Interleukin-8 / blood
  • Macaca fascicularis
  • Membrane Glycoproteins / blood*
  • Membrane Proteins / blood
  • Neutrophils / cytology*
  • RNA, Messenger / metabolism
  • Recombinant Proteins / chemistry
  • Reverse Transcriptase Polymerase Chain Reaction
  • Time Factors


  • Interleukin-6
  • Interleukin-8
  • Membrane Glycoproteins
  • Membrane Proteins
  • P-selectin ligand protein
  • RNA, Messenger
  • Recombinant Proteins
  • Granulocyte-Macrophage Colony-Stimulating Factor
  • Amyloid Precursor Protein Secretases
  • ADAM Proteins
  • ADAM10 Protein
  • ADAM10 protein, human