The C-X-C motif chemokine ligand 13 (CXCL13), a B cell attracting chemokine known to mediate the homing and motility of B cells in lymphoid tissues [36], was also up-regulated in MG compared with non-MG thymomas, suggesting that the higher degree of B cell infiltration in thymomas from MG patients could be due to CXCL13 overexpression (Figure 3D). The gene discussed is CXCL13; the disease is myasthenia gravis.