C-X-C motif ligand 13 (CXCL13), a chemokine for B cell, has been linked to multiple biological processes, including protective antibody production in autoimmune disease, and is reported as a biomarker in many inflammatory conditions such as multiple sclerosis (MS), systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and asthma (17–20). This evidence concerns the gene CXCL13 and rheumatoid arthritis.