滤泡调节性T细胞在桥本甲状腺炎中的作用

Role of follicular regulatory T cells in the pathogenesis of Hashimoto thyroiditis

目的探讨外周血滤泡调节性T细胞(Tfr)、调节性T细胞(Treg)在桥本甲状腺炎(HT)中的作用。方法检测30例HT患者和30名体检健康者血清甲状腺功能指标[游离三碘甲状腺原氨酸(FT3)、游离甲状腺素(FT4)、促甲状腺激素(TSH)、抗甲状腺球蛋白抗体(TgAb)和抗甲状腺过氧化物酶抗体(TPOAb)]及外周血Treg(CD4^+CD25^+CD127^low/-)及Tfr(CD4^+CXCR5^+CD25^+CD127^low/-)比例。根据血清甲状腺功能指标将HT患者分为甲状腺功能正常组和甲状腺功能减低组。各项目之间的相关性采用Pearson相关分析。结果HT组血清TSH及TgAb、TPOAb水平均明显高于正常对照组(P<0.05、P<0.000 1),血清FT4水平及外周血Treg比例、Tfr比例均低于正常对照组(P<0.05、P<0.001),2个组之间血清FT3水平及Tfr/Treg比值差异无统计学意义(P>0.05)。甲状腺功能正常组和甲状腺功能减低组Treg比例、Tfr比例均低于正常对照组(P<0.05、P<0.01、P<0.001);甲状腺功能减低组血清TSH及TPOAb水平均高于甲状腺功能正常组(P<0.05、P<0.01),血清FT4水平低于甲状腺功能正常组(P<0.05);2个组之间血清FT3、TgAb水平及Treg比例、Tfr比例、Tfr/Treg比值差异均无统计学意义(P>0.05)。TPOAb水平与Treg比例、Tfr比例及Tfr/Treg比值均呈负相关(r值分别为-0.428、-0.562、-0.402,P<0.05)。TgAb水平与Treg比例、Tfr比例及Tfr/Treg比值均无相关性(r值分别为-0.353、-0.178、-0.310,P>0.05)。结论Treg比例和Tfr比例降低可能参与了HT的发病。

Objective To investigate the roles of peripheral blood follicular regulatory T cells(Tfr)and regulatory T cells(Treg)in Hashimoto thyroiditis(HT).Methods A total of 30 patients with HT and 30 healthy subjects were enrolled.Free triiodothyronine(FT3),free thyroxine(FT4),thyroid stimulating hormone(TSH),anti-thyroid globulin antibody(TgAb),anti-thyroid peroxidase antibody(TPOAb)and the ratio of peripheral blood Treg(CD4^+CD25^+CD127^low/-)and Tfr(CD4^+CXCR5^+CD25^+CD127^low/-)were determined.According to the results of serum thyroid function indicators,HT patients were classified into normal thyroid function group and hypothyroid function group.The correlations were evaluated by Pearson correlation analysis.Results Serum TSH,TgAb and TPOAb levels in HT group were higher than those in healthy control group(P<0.05,P<0.0001),and serum FT4 level and peripheral blood Treg and Tfr ratios were lower than those in healthy control group(P<0.05,P<0.001).There was no statistical significance for serum FT3 level and Tfr/Treg ratio between the 2 groups(P>0.05).The ratios of Treg and Tfr in normal thyroid function group and hypothyroid function group were lower than those in healthy control group(P<0.05,P<0.01,P<0.001).Serum TSH and TPOAb levels in hypothyroid function group were higher than those in normal thyroid function group(P<0.05,P<0.01),and serum FT4 level was lower than that in normal thyroid function group(P<0.05).There was no statistical significance for serum FT3,TgAb level,Treg ratio,Tfr ratio and Tfr/Treg ratio between the 2 groups(P>0.05).TPOAb levels were negatively correlated with Treg ratio,Tfr ratio and Tfr/Treg ratio(r=-0.428,-0.562 and-0.402,P<0.05).There was no correlation of TgAb level with Treg ratio,Tfr ratio and Tfr/Treg ratio(r=-0.353,-0.178 and-0.310,P>0.05).Conclusions The decreasing of Treg and Tfr ratios may be involved in the pathogenesis of HT.