Study On CXCL13in The Occurrence Of Thymoma Complicated With Myasthenia Gravis

BackgroundMyasthenia gravis (MG) is an autoimmune neuromuscular junction disorder. Although the pathogenesis of this disease has not completely clear, But the conclusion that MG results from antibody-mediated, T cell-dependent immunologic attack on the endplate region of the postsynaptic membrane, have been broad consensus. In myasthenia gravis acetylcholine receptors antibody is n-type acetylcholine receptors (nAchR) glycoprotein polyclonal antibody. B lymphocyte is known to be the only kind of cell that could produce antibody, and it plays a very important role in humoral immunity. Chemotatic factor is a group of protein, which can stimulate cells migrating to the target tissue. Chemotatic factors Can be divided into C subfamily, CXC subfamily,CX3C subfamily and CC subfamily,according to the difference of primary structure in polypeptide chain. Chemotatic factors in CXC subfamily can effect neutrophilic granulocyte and stimulate lymphocyte obtaining chemotaxis. Chemotatic factors could bind with their specified receptors to produce a marked effect of chemotaxis. CXCL13is confirmed to be important for the formation and targeting of B-lymphocyte. It is reported that CXCL13plays a key role in several autoimmune disease, but there is rare report about the relationship between CXCL13and MG disease.33%-75%of the thymoma patients complicated with MG, while the other part of thymoma patients have no MG symptoms. Differences on such symptoms are an entry point for our study of myasthenia gravis pathogenesis.ObjectiveThis study aims to explore the meaning of CXCL13chemotactic factor on the occurrence of thymoma complicated with myasthenia gravis (MG) and analyze the relationship among CXCL13, thymoma and myasthenia gravis. MethodsEach50serum samples were collected from the patients of thymoma complicated with MG presurgery and two months after the thymusectomy in the department of thoracic surgery of the first affiliated hospital of Zhengzhou university, and50serum samples of healthy person were also collected as a comparison. Elisa method was applied to detect the level of CXCL13in the serum; RT-PCR method was introduced to evaluate the CXCL13of thymoma tissue in mRNA level. The results of the statistical analyses are shown as mean+standard deviation (x±s). The analyses were conducted with SPSS17.0software. The means of the different groups were compared using One-way analysis of variance, and a value of p<0.05was considered statistically significant.ResultThe serum CXCL13level of thymoma complicated with MG was significantly higher than that of control groups(P<0.05), two months after the thymusectomy, The serum CXCL13level was decreased than presurgery (P<0.05), the mRNA expression level of CXCL13during the thymoma tissue of thymoma complicated with MG patients was higher than that in MG patients.ConclusionThe serum CXCL13and mRNA level are statistically significance between thymoma complicated with MG and MG patients, indicating that the CXCL13has a significant meaning in the occurrence of thymoma complicated with MG.