IL15 and atherosclerosis: The former type of macrophages releases proinflammatory cytokines (e.g., interleukin (IL)-1α, IL-1β, IL-6, IL-12, IL-15, IL-18, and TNF-α), which are known to contribute to the progression of atherosclerosis, while the latter type releases anti-inflammatory cytokines (e.g., IL-10 and transforming growth factor (TGF-β), which play a critical role in inflammation resolution and plaque healing [22,23].