Suppression of tumorigenicity 2 receptor (ST2)

Suppression of tumorigenicity 2 receptor (ST2) is a member of the interleukin-1 receptor superfamily encoded by the IL1RL1 gene, located on chromosome 2q12[2][8]. It exists as both a transmembrane (ST2L) and soluble form (sST2), generated through alternative splicing[2][4]. ST2 binds interleukin-33 (IL-33) as its ligand, mediating immune responses, particularly in type 2 helper T cells and regulatory T cells, as well as influencing cardiac remodeling and fibrosis[4][8]. The sST2 isoform acts as a decoy receptor that binds IL-33 in circulation, preventing it from interacting with cell-surface ST2L, thereby attenuating IL-33/ST2 signaling. Elevated blood levels of sST2 are clinically used as prognostic biomarkers in heart failure and other cardiac and inflammatory diseases[7][3]. ST2 is under investigation as a diagnostic and therapeutic target in inflammatory, cardiovascular, and some oncologic conditions[1][8].

Other names

ST2Interleukin-1 receptor-like 1 (IL1RL1)DER4T1FIT-1

Antagonist antibodies block IL-33 binding to ST2, inhibiting downstream signaling[8]. sST2 acts as an endogenous soluble decoy receptor, sequestering IL-33 and preventing signaling via the membrane-bound receptor[7].