IL1RL1 and Myocardial fibrosis: Moreover, IL-33/IL1RL1 signaling could activate TGF-β-mediated fibroblast activation and epithelial-mesenchymal transition in the myocardium, promoting extracellular matrix (ECM) production, thereby driving myocardial fibrosis and structural remodeling characteristic of HCM (Zhu et al., 2023).