Activation-dependent surface expression of LOX-1 in human platelets.
Lectin-like oxidized LDL receptor-1 (LOX-1) was initially identified as an oxidized LDL receptor in aortic endothelial cells. Here we identified LOX-1 mRNA and protein in human platelets in addition to recent findings on the expression in macrophages and smooth muscle cells. The presence of LOX-1 was further confirmed in the megakaryocytic cell lines. Flow cytometric analyses revealed that LOX-1 was exposed on the surface of platelets in an activation-dependent manner. Consistently, the activation-dependent binding of OxLDL to platelets was mostly inhibited by anti-LOX-1 antibody. Immunohistochemistry of the atherosclerotic plaque from a patient with unstable angina pectoris (UAP) revealed accumulation of LOX-1 protein at the site of thrombus. As LOX-1 recognizes and binds activated platelets, exposure of LOX-1 on activated platelets surface might assist thrombosis formation.
National Cardiovascular Center Research Institute, Suita, Osaka, 565-8565, Japan.
M
M
Chen
M
M
Kakutani
T
T
Naruko
M
M
Ueda
S
S
Narumiya
T
T
Masaki
T
T
Sawamura
D000818:Animals; D001483:Base Sequence; D001792:Blood Platelets / Q000201:enzymology*; D016466:CHO Cells; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D006224:Cricetinae; D017931:DNA Primers; D006801:Humans; D008077:Lipoproteins, LDL / Q000378:metabolism; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics; D011973:Receptors, LDL / Q000235:genetics / Q000378:metabolism*; D051131:Receptors, Oxidized LDL; D020133:Reverse Transcriptase Polymerase Chain Reaction; D051127:Scavenger Receptors, Class E
D017931:DNA Primers; D008077:Lipoproteins, LDL; C495137:OLR1 protein, human; D012333:RNA, Messenger; D011973:Receptors, LDL; D051131:Receptors, Oxidized LDL; D051127:Scavenger Receptors, Class E; C099252:oxidized low density lipoprotein