LOX-1, an Oxidized LDL Endothelial Receptor, Induces CD40/CD40L Signaling in Human Coronary Artery Endothelial Cells

Abstract

Background— Despite increasing appreciation that atherogenesis involves participation of inflammatory cells, information on mediators of communication between different constituents of atherosclerotic plaque remain incomplete. We examined the role of LOX-1, a receptor for oxidized (ox) LDL, in the expression of CD40/CD40L in cultured human coronary artery endothelial cells (HCAECs). Methods and Results— We observed that ox-LDL increased the expression of CD40 and CD40L in a concentration (10 to 80 μg/mL)- and time (1 to 24 hours)- dependent manner. These effects of ox-LDL were mediated by activation of LOX-1, because pretreatment of HCAECs with a blocking antibody to LOX-1 (JTX92) prevented the expression of CD40 and CD40L in response to ox-LDL ( P P P Conclusions— These findings indicate that ox-LDL through its receptor LOX-1 triggers the CD40/CD40L signaling pathway that activates the inflammatory reaction in HCAECs. These observations provide novel insight into ox-LDL–mediated inflammation in atherosclerosis.