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IL-12 is a heparin-binding cytokine.
- Source :
-
Journal of immunology (Baltimore, Md. : 1950) [J Immunol] 1999 Jan 15; Vol. 162 (2), pp. 1064-70. - Publication Year :
- 1999
-
Abstract
- Using an ELISA approach, we demonstrate that recombinant human IL-12 (rhIL-12) binds strongly to an immobilized heparin-BSA complex. This binding is completely displaceable with soluble heparin, IC50 approximately 0.1 microg/ml, corresponding to approximately 10 nM. By interpolation with our previous findings, this indicates an affinity for heparin greater than that of antithrombin III and comparable with that of FGF-2, two high-affinity heparin-binding proteins. Recombinant murine IL-12 also binds strongly to heparin. The binding of rhIL-12 to heparin shows specificity because chondroitin sulfates A and C fail to compete, whereas chondroitin B inhibits weakly. A highly sulfated heparan sulfate is a strong competitor, whereas other heparan sulfates show weak or no activity. Small heparin fragments inhibit binding, although activity decreases with size. An octasaccharide pool derived by cleavage of heparin with nitrous acid is a significantly stronger inhibitor than its heparinase I-derived counterpart, further indicating structural specificity in the interaction between rhIL-12 and heparin. The binding of recombinant p40 to heparin appears indistinguishable from that of the IL-12 heterodimer, implying that the heparin binding site is largely if not solely located in this subunit. These results show for the first time that IL-12 is a heparin-binding cytokine, a property common to the other Th1-response-inducing cytokines, IFN-gamma and IL-2. Our findings strongly suggest that IL-12 will tend to be retained close to its sites of secretion in the tissues by binding to heparin-like glycosaminoglycans, thus favoring a paracrine role for IL-12.
- Subjects :
- Animals
Binding, Competitive
Carrier Proteins chemistry
Cattle
Cytokines chemistry
Cytokines metabolism
Dalteparin metabolism
Dimerization
Enzyme-Linked Immunosorbent Assay
Glycosaminoglycans metabolism
Heparin, Low-Molecular-Weight metabolism
Heparitin Sulfate metabolism
Humans
Interleukin-12 chemistry
Intestinal Mucosa
Mice
Nadroparin metabolism
Recombinant Proteins metabolism
Serum Albumin, Bovine metabolism
Swine
Tinzaparin
Carrier Proteins metabolism
Heparin metabolism
Interleukin-12 metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 0022-1767
- Volume :
- 162
- Issue :
- 2
- Database :
- MEDLINE
- Journal :
- Journal of immunology (Baltimore, Md. : 1950)
- Publication Type :
- Academic Journal
- Accession number :
- 9916734