IL33 and acute coronary syndrome: In addition, interleukin-33 (IL-33), a tissue-derived nuclear cytokine from the IL-1 family expressed in endothelial cells, epithelial cells, and fibroblast-like cells, and its unique receptor, ST2, have been shown to correlate with increased risk for all-cause death among individuals with established atherosclerotic CVD, especially in those who recently experienced an acute coronary syndrome [13].