Searching for oxidized low-density lipoproteins in vivo

Oxidized low-density lipoprotein (OxLDL) is thought to be involved in the early development of atherosclerosis through foam cell formation. It has been more than 20 years since the importance of OxLDL in atherogenesis was pointed out. During the last decade a couple of groups including ours have successfully detected OxLDL present in human circulating blood, and showed close relationship between the OxLDL levels and cardiovascular diseases. However, the actual nature of OxLDL found in vivo remained obscure until recently. In this article, a basis of the so-called "OxLDL hypothesis" on atherosclerosis will be summarized briefly, and the important issues to be solved in the near future are also discussed.