The Emerging Role of CCL17 in the Immunologic Regulation of Inflammatory Bowel Disease.

Chemokine (C-C) ligand 17 (CCL17) is a key molecule that mediates immune cell migration and inflammation. As a ligand for the type 4 C-C chemokine receptor (CCR4), CCL17 mainly affects T cells, but also influences other cell types, suggesting a broader role in immune regulation. This review comprehensively demonstrates the molecular structure and function of CCL17, its interaction with CCR4, and its involvement in the pathogenesis of inflammatory bowel disease (IBD). Additionally, we also discuss how CCL17 regulates the behavior of various immune cells, including T cells, dendritic cells, monocytes/macrophages, eosinophils, neutrophils, and fibroblasts, highlighting its involvement in the pathogenesis of IBD and its potential contribution to IBD-related colon cancer. In conclusion, this review emphasizes the important role of CCL17 in the pathogenesis of IBD and its potential as a therapeutic target.