Perlecan: a major IL-2-binding proteoglycan in murine spleen.
Although interleukin-2 (IL-2) is typically considered a soluble cytokine, our laboratory has shown that the availability of IL-2 in lymphoid tissues is regulated, in part, by an association with heparan sulfate glycosaminoglycan. Heparan sulfate is usually found in proteoglycan form, in which the heparan sulfate chains are covalently linked to a specific core protein. We now show that perlecan is one of the major IL-2-binding heparan sulfate proteoglycans in murine spleen. IL-2 binds perlecan via heparan sulfate chains, as enzymatic removal of heparan sulfate from splenic perlecan abolishes its ability to bind IL-2. Furthermore, we demonstrate that perlecan-bound IL-2 supports the proliferation of an IL-2-dependent cell line. Identification of perlecan as a major heparan sulfate proteoglycan that binds IL-2 has implications for both the localization and regulation of IL-2 in vivo.
Division of Transplantation, University of Nebraska Medical Center, Omaha, NE 68198-7690, USA. jmillerd@unmc.edu
John D
JD
Miller
Elliott T
ET
Stevens
Deandra R
DR
Smith
Thomas N
TN
Wight
Lucile E
LE
Wrenshall
D000818:Animals; D049109:Cell Proliferation; D019812:Heparan Sulfate Proteoglycans / Q000276:immunology* / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D007376:Interleukin-2 / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D013154:Spleen / Q000166:cytology / Q000276:immunology* / Q000378:metabolism
D019812:Heparan Sulfate Proteoglycans; D007376:Interleukin-2; C071927:perlecan