Immunogenic Oxidized Low-density Lipoprotein/β2-glycoprotein I Complexes in the Diagnostic Management of Atherosclerosis

Oxidized low-density lipoprotein (oxLDL) promotes atherosclerosis through a complex interaction of inflammatory and immunologic factors that lead to macrophage lipid uptake and foam cell formation. OxLDL interacts with beta 2-glycoprotein I (beta 2GPI) forming oxLDL/beta 2GPI complexes. These complexes may be formed in the arterial intima during atherogenesis and released into the circulation. Autoantibodies against oxLDL/beta 2GPI complexes have been demonstrated in patients with systemic lupus erythematosus and/or antiphospholipid syndrome, and shown to be significantly associated with arterial thrombosis. The observation that monoclonal autoantibodies against oxLDL/beta 2GPI complexes significantly increased the oxLDL uptake by macrophages strongly suggests that such IgG autoantibodies are pro-atherogenic. In this article, we review the recent progress in our understanding of LDL oxidation, oxLDL/beta 2GPI complex formation, and immune regulation of atherogenesis.