An overview of the pathogenesis of atherosclerosis. The influence of high-density lipoprotein (HDL) and oxidized low-density lipoprotein (oxLDL) on atherosclerosis is one part of the story, as shown in the open circle on the right. However, many other processes impact on arterial health, including additional factors influencing inflammation, oxidation, and the immune response. Proinflammatory HDLs (piHDLs) play a role in each of these processes. EC, endothelial cell; IFNγ, interferon-gamma; IL, interleukin; iNOS, inducible nitric oxide synthase; L, lymphocyte; M, monocyte; MCP-1, monocyte chemotactic protein-1; OxPL, oxidized phospholipid; TNFα, tumor necrosis factor-alpha.