Interleukin-2 is present in human blood vessels and released in biologically active form by heparanase

Immunol Cell Biol. 2012 Feb;90(2):159-67. doi: 10.1038/icb.2011.45. Epub 2011 May 24.


Interleukin-2 (IL-2) is a multifaceted cytokine with immunostimulatory and immunosuppressive properties. Our laboratory recently demonstrated that the availability of IL-2 is regulated, in part, by association with perlecan, a heparan sulfate proteoglycan. Given the abundance of perlecan in blood vessels, we asked whether IL-2 is present in vessel walls. Our results indicate that IL-2 is associated with endothelial and smooth muscle cells within the human arterial wall. This IL-2 is released by heparanase, and promotes the proliferation of an IL-2-dependent cell line. Given the presence of IL-2 in human arteries, we asked whether the large vessels of IL-2-deficient mice were normal. The aortas of IL-2-deficient mice exhibited a loss of smooth muscle cells, suggesting that IL-2 may contribute to their survival. In their entirety, these results suggest a here-to-fore unrecognized role of IL-2 in vascular biology, and have significant implications for both the immune and cardiovascular systems.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Aortic Aneurysm / metabolism
  • Arteries / cytology
  • Arteries / metabolism
  • Cells, Cultured
  • Endothelial Cells / metabolism
  • Endothelium, Vascular / metabolism*
  • Extracellular Matrix Proteins / metabolism
  • Glucuronidase / metabolism*
  • Heparan Sulfate Proteoglycans / metabolism
  • Humans
  • Interleukin-2 / metabolism*
  • Mice
  • Mice, Knockout
  • Muscle, Smooth, Vascular / metabolism*
  • Receptors, Interleukin-2 / metabolism


  • Extracellular Matrix Proteins
  • Heparan Sulfate Proteoglycans
  • Interleukin-2
  • Receptors, Interleukin-2
  • perlecan
  • heparanase
  • Glucuronidase