C-X-C chemokine receptor type 3 (CXCR3) (CXCR3)

C-X-C chemokine receptor type 3 (CXCR3) is a seven-transmembrane G protein-coupled receptor (GPCR) primarily expressed on activated Th1 lymphocytes, CD8+ cytotoxic T cells, and natural killer (NK) cells (UniProt: P49682). It is activated by three interferon-gamma (IFN-γ)-inducible ligands: CXCL9 (MIG), CXCL10 (IP-10), and CXCL11 (I-TAC), which trigger intracellular signaling pathways to induce chemotaxis and cellular activation (PMID: 30613114). In pathological states, the CXCR3 axis is a key driver of the recruitment of inflammatory cells into tissues, contributing to the progression of autoimmune diseases like rheumatoid arthritis, multiple sclerosis, and type 1 diabetes (PMID: 28250599). In the context of oncology, CXCR3 expression on tumor-infiltrating lymphocytes is generally associated with improved prognosis due to enhanced anti-tumor immunity, although its expression on certain tumor cells can facilitate metastasis (PMID: 25614325). Pharmaceutical development has focused on small molecule CXCR3 antagonists, such as AMG-487 and ACT-777991, to treat inflammatory conditions by preventing the infiltration of pathogenic T cells (PMID: 17003437). Despite promising preclinical data, clinical success has been limited by the inherent redundancy of the chemokine system and the complex, context-dependent roles of CXCR3 in different disease environments.

Other names

CD183G protein-coupled receptor 9GPR9IP-10 receptorCKR-L2CMKAR3

CXCR3 antagonism (competitive inhibition of ligand binding to the receptor to prevent downstream signaling and chemotaxis)