重症肌无力患者外周血中IL-21的表达及其与血清抗AChR抗体类别转换的关系  

Expression of IL-21 in the peripheral blood of myasthenia gravis patients and its correlation with anti-AChR-Ab class switch

作　　者：胡波[1] 田晓琳[1] 黄慧芬[1] 翦爱[1] 欧阳松[1] 尹炜凡[1] 段维维[1] 杨欢[1] 

机构地区：[1]中南大学湘雅医院神经内科,长沙410008

出　　处：《中南大学学报（医学版）》2010年第9期958-963,共6页Journal of Central South University ：Medical Science

基　　金：国家自然科学基金(30870857);湖南省自然科学基金(09JJ3079)~~

摘　　要：目的:探讨白细胞介素(IL)-21在重症肌无力(MG)发病中的作用及其对血清抗乙酰胆碱受体(AChR)抗体类别转换的影响。方法:采集26例MG患者和18例健康对照者的外周血,应用ELISA技术检测外周血血清中抗AChR-IgG及其亚型IgG1,IgG2,IgG3的水平以及IL-21的浓度,利用RT-PCR技术检测外周血单个核细胞上IL-21RmRNA的表达水平,采用流式细胞学技术检测其中8例患者B细胞上IL-21R的表达水平,并分析它们之间的关系。结果:MG患者组血清中IL-21浓度(31.686±8.499pg/mL)高于正常对照组(15.147±6.366 pg/mL),差异具有统计学意义(P<0.01);MG患者组PB-MCs上IL-21RmRNA的表达(0.139±0.052)高于正常对照组(0.101±0.022),差异具有统计学意义(P<0.05);但二者在眼肌型和全身型亚组中差异均无统计学意义(P>0.05)。8例MG患者B细胞上的IL-21R的表达水平(1.074±0.375)高于正常对照组(0.389±0.391),差异具有统计学意义(P<0.05)。抗AChR-Ab阳性患者血清IL-21浓度与抗AChR-IgG水平呈正相关,相关系数为0.689(P<0.05),但其与IgG1,IgG2,IgG3亚型的水平均无相关性(P>0.05);PBMCs上IL-21RmRNA的表达与血清抗AChR-IgG及其IgG1,IgG2,IgG3亚型的水平均无相关性(P>0.05);B细胞上IL-21R的表达与抗AChR-IgG及IgG1,IgG3亚型水平呈正相关(分别为P<0.05,P<0.01,P<0.05),而与抗AChR-IgG2的水平无相关性(P>0.05)。结论:IL-21可能通过作用于B细胞上的IL-21R,影响MG患者血清中抗AChR抗体向IgG1和IgG3亚型转换,从而对MG发病起促进作用。Objective To explore the role of IL-21 in the pathogenesis of myasthenia gravis（MG） and its influence on the the class switch of anti-AChR antibodies.Methods Blood was taken from 26 patients and 18 healthy controls,and the expression of IL-21R mRNA in peripheral blood mononuclear cells（PBMCs） was detected by RT-PCR.The expression of IL-21R on B lymphocytes was measured by flow cytometry,while the concentrations of serum IL-21 and the levels of anti-AChR-IgG and its isotype IgG1,IgG2,and IgG3 were tested by ELISA.Results The serum concentration of IL-21 in the MG group was higher than that in the control group（31.686±8.499 pg/mL,15.147±6.366 pg/mL） and the difference was significant（P〈0.01）.IL-21R mRNA expressed on PBMCs in the MG group was higher than that in the control group（0.139±0.052,0.101±0.022）,and the difference was significant（P〈0.05）.There was no difference between ocular MG and generalized MG subgroup（P〉0.05）.Compared with the control group,the expression of IL-21R on B lymphocytes also increased in the MG group（P〈0.05）.In the anti-AChR-Ab positive MG group,the serum concentration of IL-21 showed positive correlation with anti-AChR-IgG（P〈0.05）,but no correlation with its isotype IgG1,IgG2,and IgG3,respectively（P〉0.05）.Expression of IL-21R mRNA in the PBMCs showed no correlation with the level of serum anti-AChR-IgG and its isotype IgG1,IgG2,and IgG3,respectively（P〉0.05）;however the expression of IL-21R in B lymphocytes showed positive correlation with anti-AChR-IgG and it＇s isotype IgG1 and IgG3（P〈0.05,P〈0.01,P〈0.05）,but no correlation with IgG2（P〉0.05）.Conclusion IL-21 might induce the class switch of anti-AChR antibodies to IgG1 and IgG3 isotype through IL-21R on B lymphocytes which promotes the pathogenesis of the MG.

关 键 词：重症肌无力 白细胞介素21 白细胞介素21受体 抗乙酰胆碱受体抗体 抗体类别转换 

分 类 号：R746.1[医药卫生—神经病学与精神病学]