In fact, the pathological role of XCL1-XCR1 axis has been implicated in numerous chronic inflammatory diseases, including rheumatoid arthritis, inflammatory arthritis, Crohn's disease, acute allograft rejection, autoimmune disorders, encephalomyelitis, crescentic glomerulonephritis, and inflammatory bowel disease (18–23). The gene discussed is XCR1; the disease is inflammatory bowel disease.