M1 macrophages, induced by stimuli such as interferon-gamma (IFN-γ) and lipopolysaccharide (LPS), secrete pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and reactive oxygen species (ROS), thereby amplifying vascular inflammation and contributing to endothelial dysfunction and plaque instability [253]. The gene discussed is IL1B; the disease is endothelial dysfunction.