CCL20 is a chemokine that serves as the exclusive high-affinity ligand for chemokine receptor CCR6, playing crucial roles in immune cell trafficking and inflammatory responses 1. The primary function involves mediating chemotaxis of various immune cells including dendritic cells, T cells, and B cells through CCR6 binding and calcium mobilization 1. CCL20 is predominantly produced by epithelial cells and hepatic progenitor cells/cholangiocytes, with expression significantly increased under inflammatory conditions 12. In autoimmune diseases, the CCR6-CCL20 axis facilitates recruitment of pathogenic immune cells to inflammation sites, with genome-wide association studies showing strong correlations between CCR6 expression and disease severity in inflammatory bowel disease, psoriasis, rheumatoid arthritis, and multiple sclerosis 1. The chemokine promotes IL-17A-producing Th17 cell recruitment in psoriasis, creating feed-forward inflammatory loops 3. In cancer contexts, CCL20 contributes to tumor progression by recruiting immunosuppressive regulatory T cells and promoting macrophage M2 polarization in colorectal and hepatocellular carcinomas 45. Additionally, CCL20 plays roles in metabolic dysfunction-associated steatohepatitis by promoting cholesterol deposition in hepatocytes through the CCR6-JNK-OLR1 pathway 2. CCL20 also serves as a potential biomarker for preeclampsia 6.