Heparin also interacts with selectins and modulates the cell adhesion process.

Abstract

To the Editor: We read with great interest the article by Peter and coworkers1 in the October 5, 1999 issue of Circulation in which the authors demonstrated the binding of heparin to integrin Mac-1 on stimulated leukocytes. Recent investigations have revealed that heparin can modulate biological processes, such as binding to adhesion receptors on endothelial cells and leukocytes.2 Leukocyte adhesion is a complex molecular process, and multiple adhesion receptor systems mediate the recruitment of leukocytes from the blood. The initial trafficking of circulating leukocytes to sites of inflammation is mediated by the selectin family of adhesion receptors; this is followed by the engagement of additional cellular recognition receptors, including the immunoglobulin superfamily and integrins. Heparin interacts with adhesion molecules, including integrin Mac-1 (CD11b/CD18) and selectins.3 4 Peter …