[OxLDL/β2-glycoprotein I complex as a pro-atherogenic autoantigen. Is atherosclerosis an autoimmune disease?]

Oxidation of atherogenic low-density lipoproteins (LDL) plays a key role in the pathogenesis of atherosclerosis. Oxidation stress and inflammation are closely interrelated and they can potentiate one another. In the subendothelial space of the arterial intima, monocytes/macrophages become activated and phagocyte oxidized LDL (oxLDL) via scavenger receptors. It has been demonstrated that oxLDL forms complex with plasma β2-glycoprotein I (β2GPI) and becomes autoantigenic triggering synthesis of specific antiphosholipid antibodies. It has been documented that oxLDL/β2GPI in immune complex with IgG autoantibody is internalized by macrophages through the Fcγ receptor. Increased levels of oxLDL/β2GPI were first observed in patients with systemic lupus erythematodes (SLE) and antiphospholipid syndrome (APS), further in individuals with coronary heart disease (CHD) and type 2 diabetes mellitus (DM2T). In a prospective study, initial plasma concentrations of oxLDL/β2GPI correlated with the number and severity of cardiovascular events in patients with chronic CHD over a 2-year period.Key words: atherosclerosis - β2-glycoprotein I - inflammation - oxidative stress - oxLDL.