他克莫司治疗重症肌无力作用机制的研究

The Therapeutic Mechanism of Tacrolimus on Myasthenia Gravis

目的:研究他克莫司治疗重症肌无力(MG)的免疫调节机制。方法:收集依据临床表现、实验室和电生理检查确诊的全身型MG患者外周血28份(来自22例患者),健康对照外周血20份(来自20名健康者)。分离单核细胞,稀释后等量分为4份,分别加入他克莫司0、2、10及50 ng·mL^(-1),培养48 h后收集上清液,以ELISA法检测上清液中IL-12、IL-2、IFN-γ、IL-4、IL-10、IL-13、TNF-α、sICAM-1的浓度。结果:对照组随他克莫司浓度的升高(0、2、10和50 ng·mL^(-1)),IL-2、IL-10的浓度显著升高(P<0.05),TNF-α水平有降低趋势,但差异无统计学意义(P<0.05)。MG组IL-12、IL-2、IFN-γ、IL-10、IL-13和sICAM-1的水平均显著升高(P<0.05),而TNF-α水平明显降低(P<0.05)。结论:他克莫司不是一个单纯的免疫抑制剂。它能抑制炎性因子TNF-α和黏附分子的分泌,诱导和影响Th1和Th2细胞因子产生,最终达到治疗MG的效果。

Aim：To investigate the therapeutic mechanisms of tacrolimus on patients with myasthenia gravis （MG）, focusing on soluble cytokines. Methods：28 peripheral blood samples were recruited from 22 general type MG patients who were diagnosed from clinical symptoms, laboratory tests and EMG by two or more neurological doctors. And there were 20 peripheral blood samples from 20 healthy controls.Then peripheral blood mononuclear cells（MNC） were isolated by density gradient centrifugation on Lymphoprep, and divided into 4 parts. Each part was cultured with Tacrolimus of different concentrations（0, 2, 10 and 50 ng.mL^-1 respectively） at 37℃ for 48 hours. Finally, The supernatants were collected, and soluble cytokines （IL-12, IL-2, IFN-γ, IL-4, IL-10, IL-13 and TNF-αand adhesion molecule（sICAM-1） were measured by ELISA. Results：Tacrolimus significantly elevated the production of Thl cytokines（IL-2） and Th2 cytokines（IL-10） in healthy controls（P〈0.05）, and did not inhibit the production of TNF-α significantly（P〉0.05）. However, tacrolimus increased the production of Thl cytokines（IL-2 and IFN-γ） and Th2 cytokines（IL-4 and IL-10） in patients （P〈0.05）, as well as the production of sICAM-1（P〈0.05）, while it significantly decreased the production of TNF-α Conclusion： Tacrolimus is not as simple as an immunosuppressive drug. It inhibits the secretion of inflammatory cytokine, but induces production of Th1/Th2 cytokines and sICAM-1.