BACKGROUND: Atherosclerosis is a chronic inflammatory disease characterized by lipid-driven immune dysregulation. Argininosuccinate synthase 1 (ASS1) has been implicated in macrophage inflammation, yet its precise mechanistic role in foam cell-mediated vascular injury during atherosclerosis remains unclear. This study investigates whether ASS1 promotes disease progression via the NLRP3/IL-33/ST2 axis. METHODS: An in vitro foam cell model was established using phorbol 12-myristate 13-acetate (PMA...