alexa Macrophage and foam cell release of matrix-bound growth factors. Role of plasminogen activation.


Journal of Clinical & Experimental Dermatology Research

Author(s): Falcone DJ, McCaffrey TA, HaimovitzFriedman A, Vergilio JA, Nicholson AC

Abstract Share this page

Abstract We have determined whether macrophage derived-foam cells, a prominent component of the atherosclerotic lesion, express more urokinase-type plasminogen activator (uPA) and whether their ability to generate plasmin stimulates the release of matrix-bound growth factors. Steady state levels of uPA mRNA and both membrane and intracellular uPA activities were significantly increased in foam cells. When cultured on cell-derived matrices containing bound 125I-basic fibroblast growth factor (bFGF), both macrophage and foam cells released intact 125I-bFGF into their media. The release of 125I-bFGF by either cell was significantly enhanced in the presence of plasminogen. However, foam cells, which expressed more membrane uPA, released more 125I-bFGF than control cells. The release of matrix-bound bFGF was independent of heparanase activity, since neither macrophage nor foam cells degraded 35SO4-labeled heparan sulfate proteoglycans. In addition, media derived from foam cells cultured on cell-derived matrices in the presence of plasminogen had increased levels of transforming growth factor (TGF) beta activity as compared to cells grown in the absence of plasminogen. In contrast, plasminogen had no effect on TGF-beta activity recovered in the media of foam cells grown on plastic. Moreover, when macrophage were cultured on matrices containing bound 125I-TGF-beta, the release of labeled TGF-beta was increased in the presence of plasminogen. This is the first demonstration that foam cells can release two important growth regulators, bFGF and TGF-beta, from the extracellular matrix, and provides a mechanism by which macrophage and foam cells can stimulate atherosclerotic lesion development.
This article was published in J Biol Chem and referenced in Journal of Clinical & Experimental Dermatology Research

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version