AN ENDOTHELIAL RECEPTOR FOR OXIDIZED LOW-DENSITY-LIPOPROTEIN

Endothelial dysfunction or activation elicited by oxidatively modified low-density lipoprotein (Ox-LDL) has been implicated in the pathogene sis of atherosclerosis(1-4), characterized by intimal thickening and l ipid deposition in the arteries. Ox-LDL and its lipid constituents imp air endothelial production of nitric oxide, and induce the endothelial expression of leukocyte adhesion molecules and smooth-muscle growth f actors, which may be involved in atherogenesis(5-7). Vascular endothel ial cells in culture(8,9) and in vivo(10,11) internalize and degrade O x-LDL through a putative receptor-mediated pathway that does not invol ve macrophage scavenger receptors(12-15). Here we report the molecular cloning, using expression cloning strategy, of an Ox-LDL receptor fro m vascular endothelial cells. The cloned receptor is a membrane protei n that belongs structurally to the C-type lectin family, and is expres sed in vivo in vascular endothelium and vascular-rich organs.