Ectopic and high CXCL13 chemokine expression in myasthenia gravis with thymic lymphoid hyperplasia

Myasthenia gravis (MG) is an antibody and complement mediated autoimmune disease. Serum CXC chemokine ligand 13 (CXCL13) was found to be elevated in MG patients and high CXCL13 level was associated with severe clinical stages, especially in females with thymic lymphoid hyperplasia. Both protein and mRNA of CXCL13 and CXC chemokine receptor 5 (CXCR5) in the thymic tissues were significantly higher in MG patients with lymphoid hyperplasia than those with thymoma. Our data indicated that serum CXCL13 can be used as an index of disease severity and ectopic thymic expression of CXCL13 might be associated with aberrant cell trafficking to the thymus of MG.