·临床免疫学·儿童持续性免疫性血小板减少性紫癜患儿滤泡辅助性T细胞改变初探姚鑫李成荣王国兵杨军李长钢DOI:10.3760/cma.j.issn.0254-5101.2013.11.007基金项目:深圳市重点科技计划项目基金(201201005)作者单位:518026遵义医学院深圳市儿童医院儿科研究所通信作者:李成荣,Email:lichengrong_sz@163.com,电话:0755-83936273【摘要】目的探讨滤泡辅助性T细胞(Tfollicularhelper,Tfh)在儿童持续性免疫性血小板减少性紫癜(persistentimmunethrombocytopenicpurpura,pITP)免疫发病机制中的可能作用。方法pITP患儿20例,采用流式细胞术检测外周血循环CD4+CXCR5+ICOShighPD-1highT(cTfh)细胞比例及CD19+B细胞ICOSL(inducibleco-stimulatorligand)的表达,采用实时荧光定量PCR(real-timePCR)检测Bcl-6、c-Maf、IL-21mRNA及CD19+B细胞ICOSLmRNA表达,酶联免疫吸附试验检测血浆IL-2、IL-6、IL-21浓度。结果(1)pITP患儿cTfh细胞比例明显高于正常对照组[(17.45±9.04)%vs(7.57±2.57)%,P<0.05],地塞米松(DEX)治疗7d后cTfh细胞比例明显低于治疗前[(5.93±1.64)%vs(17.45±9.04)%,P<0.05];(2)Tfh细胞转录调节因子Bcl-6及c-Maf表达较正常对照组明显增高(P<0.05);(3)pITP患儿CD19+B细胞ICOSL蛋白和基因表达明显增高(P<0.05),DEX治疗后CD19+B细胞ICOSL表达与治疗前相比无明显改变(P>0.05);(4)Tfh细胞相关细胞因子IL-21血浓度和基因表达水平明显高于正常对照组(P<0.05),DEX治疗后仍显著高于对照组(P<0.05),IL-2及IL-6血浆浓度治疗前后与正常对照组相比无明显改变(P>0.05)。结论ICOSL和IL-21表达异常所致Tfh细胞过度活化可能与pITP患儿免疫发病机制有关;B细胞持续高表达ICOSL和IL-21持续高水平可能是导致pITP患儿病情反复发作的原因之一。【关键词】滤泡辅助性T细胞;Bcl-6;ICOSL;IL-21;免疫性血小板减少性紫癜AlterationofTfollicularhelpercellsinchildrenwithpersistentimmunethrombocytopenicpurpuraYAOXin,LICheng-rong,WANGGuo-bing,YANGJun,LIChang-gang.DepartmentofMolecularImmunol-ogy,ShenzhenInstituteofPediatrics,ShenzhenChildren′sHospital,ZunyiMedicalCollege,Shenzhen518026,ChinaCorrespondingauthor:LICheng-rong,Email:lichengrong_sz@163.com【Abstract】ObjectiveToinvestigatetheroleofTfollicularhelper(Tfh)cellsintheimmuno-pathogenesisofpersistentimmunethrombocytopenicpurpura(pITP).MethodsTwentychildrenwithpITPandtwentyhealthycontrolswereenrolledinthisstudy.TheproportionofCD4+CXCR5+ICOShighPD-1highT(cTfh)cellsandtheexpressionofICOSLonCD19+Bcellsinperipheralbloodofthepatientsandhealthysubjectswereanalyzedbyflowcytometry.TheexpressionsofBcl-6,c-Maf,IL-21andICOSLatmRNAlevelweredetectedbyreal-timePCR.Theplasmaconcentrations...