For instance, the CXC-chemokines (CXCL5, CXCL8, CXCL9, CXCL10, CXCL12, CXCL13 and CXCL16), the CC-chemokines (CCL2, CCL3, CCL4, CCL5, CCL18, CCL19, CCL20, CCL21, CCL25), and the CX3C-chemokine CX3CL1 are increased in serum, synovial fluid, and synovial tissue of RA patients, compared with healthy controls (10), (11), (12), (13), (14), (15). Here, CXCL12 is linked to rheumatoid arthritis.