Natural killer cells in the innate immunity network of atherosclerosis

Natural killer (NK) cells are innate lymphocytes which have recently been proposed to play an immunoregulatory role in the pathogenesis and progression of atherosclerosis. Although several studies have evaluated the frequency and the functions of NK cells both in human and in experimental animal models of atherosclerosis, it is yet not clear whether NK cells might behave as protective or pro-atherogenic effectors. Here, we review current knowledge regarding the role of NK cells in atherosclerosis and discuss the potential interactions that might occur in atherosclerotic lesions between NK cells and antigen presenting cells, such as macrophages and dendritic cells. A clearer depiction of the innate immune cell network operating in atherosclerosis might pave the way to novel interesting approaches for the prevention and treatment of this disease.