| Background:Myasthenia gravis(MG)is an acquired autoimmune disease(AID),caused mainly by acetylcholine receptor auto-antibodies(AChR-Ab)at the neuromuscular junction(NMJ).MG is mainly characterized by skeletal muscle weakness,fatigue and volatility.It has been clear that the interaction between T and B cells leads to the formation of AChR-Ab.Pathogenic AChR-Ab is a high affinity for IgG.T-helper 22(Th22)cells are a new CD4+ T-helper subset,characterized by the secretion of cytokines Interleukin-22(IL-22).Th22 cells and IL-22 play an important role in many autoimmune diseases.However,their changes in various diseases are not the same.In patients with rheumatoid arthritis(RA)and idiopathic thrombocytopenic purpura(ITP),the percentage of Th22 cells in peripheral blood mononuclear cells(PBMCs)and the expression of IL-22 in serum were significantly higher than those in healthy controls(HC);however,in patients with aplastic anemia(AA)and systemic lupus erythematosus nephritis(LN),the percentage of Th22 cells in PBMCs and the expression of IL-22 in serum were significantly reduced.Up to now,the research about Th22 cells in PBMCs of patients with MG has not been reported at home and abroad.Therefore,it is very important to further explore the related mechanism of Th22 cells in the pathogenesis of MG,that investigate the expression of Th22 cells in PBMCs and IL-22 in serum of MG with patients,and their correlations with AChR-Ab.Objective:To investigate the expression of Th22 cells in PBMCs and related cytokines in serum of MG with patients,and the correlations among Th22 cells,IL-22 and AChR-Ab,which provide a new research basis for the pathogenesis of MG.Methods:25 patients with MG and 24 healthy controls were recruited.The percentage of Th22 cells in PBMCs of patients with MG and healthy controls was detected by flow cytometry.The levels of IL-22 and AChR-Ab in serum were detected by enzyme-linked immunosorbent assay(ELISA).Compared the percentage of Th22 cells,the levels of IL-22 and the expression of AChR-Ab between the patients with MG and healthy controls respectively,and analyzed the correlations among Th22,IL-22 and AChR-Ab.Results:The percentage of Th22 cells in PBMCs of patients with MG was significantly lower than that of healthy controls,[(0.60 ± 0.07)% versus(0.92 ± 0.09)%,P <0.01].The percentage of Th22 cells in PBMCs of ocular myasthenia gravis(OMG)was higher than that of generalized myasthenia gravis(GMG),[(0.64±0.10)% versus(0.55±0.09)%,P> 0.05].The levels of IL-22 in serum of patients with MG was significantly lower than that of healthy controls,[(18.65±1.38)pg/ml versus(24.54±1.85)pg/ml,P <0.05].The levels of IL-22 in serum of OMG was higher than that of GMG,[(20.82±1.92)pg/ml versus(15.89±1.69)pg/ml,P> 0.05 ].The optical density(OD)value of AChR-Ab in serum of patients with MG was significantly higher than that of healthy controls,[(0.27±0.04)versus(0.17±0.03),P <0.05].The OD value of AChR-Ab in serum of patients with OMG was lower than that of GMG,[(0.22±0.03)versus(0.34±0.07),P >0.05].The percentage of Th22 cells in PBMCs of patients with MG was positively correlated with the expression of IL-22 in serum,r = 0.55,P <0.01;The expression of AChR-Ab in serum of patients with MG was negatively correlated with the percentage of Th22 cells,r=-0.50,P <0.05;The expression of AChR-Ab in serum of patients with MG was negatively correlated with the expression of IL-22,r=-0.64,P <0.01.Conclusions:The decrease of the proportion of Th22 cells and the expression of IL-22 may be involved in the pathogenesis of MG.AChR-Ab and Th22,AChR-Ab and IL-22 were all significantly negative correlation.The above indicated that Th22 cells and IL-22-mediated immune disorders may be affected by the secretion of AChR-Ab,which in turn affected the incidence of MG. |
