CAJ | 학술논문

目的观察原发免疫性血小板减少症(ITP)患儿外周血滤泡调节性T细胞(Tff)、滤泡辅助性T细胞(Tfh)变化,探讨其在ITP发病机制中的作用.方法 32例ITP患儿纳入研究,男18例、女14例,中位年龄2岁7个月(8个月～10岁);以健康体检儿童20名(男、女各10名)为对照组.用流式细胞术检测ITP患儿外周血Tfr细胞(CD4+Foxp3+CXCR5+ICOS+)、Tfh细胞(CD4+ CXCR5+ICOS+)比例及Tfr/Tfh比值变化;实时荧光定量PCR法检测转录及调控因子Bcl-6、c-MAF、Blimp-1、PD-1 mRNA表达变化;ELISA法检测血浆IL-2、IL-6、IL-10、IL-21浓度.结果 ①与对照组比较,ITP患儿外周血Tfr细胞比例降低[(2.16±1.31)％对(5.31±1.68)％,P＜0.05],Tfh细胞比例增高[(17.30±7.47)％对(8.28±3.83)％,P＜0.05],Tfr/Tfh比值降低(0.15±0.10对0.43±0.29,P＜0.05);②ITP患儿Tfr细胞比例及Tfr/Tfh比值与外周血血小板计数呈正相关、与PA-IgG水平呈负相关,而Tfh细胞比例与PA-IgG呈正相关、与血小板计数呈负相关;③CD4+T细胞Bcl-6及c-MAF mRNA表达明显增高,转录抑制因子Blimp-1 mRNA表达低于对照组;调节性T细胞PD-1 mRNA明显降低;④血浆细胞因子IL-2浓度降低,IL-21浓度增高.结论 ①外周血Tfr细胞比例减少、Tfh细胞比例增加、Tfr/Tfh比值失衡可能参与了儿童ITP的发病过程,Tfr、Tfh细胞及其比值异常可能是造成ITP患儿血小板数量减少的主要原因之一;②转录及调控因子Bcl-6、c-MAF mRNA和调节性T细胞PD-1 mRNA过表达,以及局部微环境IL-2、IL-21浓度改变可能与Tfr/Tfh细胞分化失衡有关.
목적 관찰원발면역성혈소판감소증(ITP)환인외주혈려포조절성T세포(Tff)、려포보조성T세포(Tfh)변화,탐토기재ITP발병궤제중적작용.방법 32례ITP환인납입연구,남18례、녀14례,중위년령2세7개월(8개월～10세);이건강체검인동20명(남、녀각10명)위대조조.용류식세포술검측ITP환인외주혈Tfr세포(CD4+Foxp3+CXCR5+ICOS+)、Tfh세포(CD4+ CXCR5+ICOS+)비례급Tfr/Tfh비치변화;실시형광정량PCR법검측전록급조공인자Bcl-6、c-MAF、Blimp-1、PD-1 mRNA표체변화;ELISA법검측혈장IL-2、IL-6、IL-10、IL-21농도.결과 ①여대조조비교,ITP환인외주혈Tfr세포비례강저[(2.16±1.31)％대(5.31±1.68)％,P＜0.05],Tfh세포비례증고[(17.30±7.47)％대(8.28±3.83)％,P＜0.05],Tfr/Tfh비치강저(0.15±0.10대0.43±0.29,P＜0.05);②ITP환인Tfr세포비례급Tfr/Tfh비치여외주혈혈소판계수정정상관、여PA-IgG수평정부상관,이Tfh세포비례여PA-IgG정정상관、여혈소판계수정부상관;③CD4+T세포Bcl-6급c-MAF mRNA표체명현증고,전록억제인자Blimp-1 mRNA표체저우대조조;조절성T세포PD-1 mRNA명현강저;④혈장세포인자IL-2농도강저,IL-21농도증고.결론 ①외주혈Tfr세포비례감소、Tfh세포비례증가、Tfr/Tfh비치실형가능삼여료인동ITP적발병과정,Tfr、Tfh세포급기비치이상가능시조성ITP환인혈소판수량감소적주요원인지일;②전록급조공인자Bcl-6、c-MAF mRNA화조절성T세포PD-1 mRNA과표체,이급국부미배경IL-2、IL-21농도개변가능여Tfr/Tfh세포분화실형유관.
Objective To investigate the changes and roles of follicular regulatory T cells (Tfr) and follicular T helper cells (Tfh) in the pathogenesis of children immune thrombocytopenia (ITP).Methods 32 untreated ITP patients,as well as 20 healthy controls were enrolled in this study.The proportion of circulating Tfr and Tfh cells were determined by flow cytometry; real-time PCR was performed to detect the expression of transcription factors and regulatory factors of Bcl-6,c-Maf,Blimp-1 and PD-1 mRNA; ELISA was used to detect plasma concentration of IL-2,IL-6,IL-10 and IL-21.Results ①The proportion of Tfh cells were significantly higher (P＜0.05),while the Tfr cells and the ratio of tfr/Tfh cells in ITP patients were significantly lower than that in health controls (P＜0.05); ② Correlation analysis showed that the Tfr cells and the ratio of Tff/Tfh were positively correlated with the platelet counts and negatively with the levels of PA-IgG,while the proportion of Tfh cells was positively correlated with the levels of PA-IgG and negatively with the platelet counts in peripheral blood; ③ Transcription levels of Bcl-6 and c-Maf mRNA in CD4+ T lymphocytes cells were significantly elevated,the Blimp-1 mRNA in CD4+ cells and PD-1 mRNA levels of Treg were lower in ITP patients in comparison with healthy controls; ④The higher Plasma concentration of IL-21,and lower concentration of IL-2 were found in ITP patients.Conclusion ①The lower proportion of Tfr cells and higher proportion of Tfh cells,as well as the abnormal ratio of Tfr/Tfh might account for the decreased platelet counts to be further involved in the immunological pathogenesis of children ITP; ② The changes of plasma cytokines IL-2,IL-21 in microenvironment and the over-expression of Bcl-6 mRNA,c-Maf mRNA and the lowerexpression of Blimp-1 mRNA in CD4+ T cells,and over-expression of PD-1 mRNA in Treg cells might be account for the abnormal ratios of Tfr/Tfh cells in ITP patients.