CD4~＋CD25~＋FoxP3~＋免疫调节细胞在不同免疫应答状态乙型肝炎疫苗接种者中的表达(英文)

CD4^+CD25^+ FoxP3^+ T regulatory cells in subjects responsive or unresponsive to hepatitis B vaccination

目的:通过对乙型肝炎病毒疫苗接种后不同免疫应答人群CD4+CD25+T调节细胞(T regulatorycells,Tregs)及FoxP3 mRNA的表达及细胞因子分泌的检测,探讨乙型肝炎病毒疫苗接种后免疫应答与免疫调节细胞和细胞因子之间的内在联系。方法:采集不同反应人群(应答组18例,无应答组22例,对照组10例)全血,流式细胞术对外周血单核细胞的表面标志物CD4和CD25进行检测;实时荧光定量PCR检测人外周血单个核细胞FoxP3 mRNA的表达;酶联免疫吸附实验(ELISA)检测外周血单个核细胞经植物血凝素(phytohe-magglutinin,PHA)和乙型肝炎表面抗原(hepatitis B surface antigen,HBsAg)刺激后IL-4,IL-12,IL-18,IFN-γ的产生水平。结果:无应答组外周血CD4+CD25+Tregs占CD4+T细胞的百分比明显高于应答组(P<0.05),但低于对照组(P<0.01)。PHA和HBsAg刺激前后,无应答组FoxP3的表达均高于应答组和对照组(P<0.01或P<0.05)。各组外周血单个核细胞经PHA和HBsAg刺激后,无应答组的IFN-γ浓度明显低于应答组和对照组(P<0.05)。各组外周血单个核细胞经PHA和HBsAg刺激后,IL-18,IL-4和IL-12的浓度差异均无统计学意义(P>0.05)。结论:CD4+CD25+FoxP3+Tregs在一定程度上参与了乙型肝炎疫苗接种应答的负性调控;乙型肝炎病毒疫苗接种后无应答可能与IFN-γ分泌不足有关。

Objective To determine CD4＋CD25＋ T regulatory cells（Tregs）,forkhead box P3（FoxP3） mRNA expression and levels of cytokines secreted by peripheral blood mononuclear cells（PBMCs） in individuals responsive or unresponsive to hepatitis B（HB） vaccination,and to explore the relationships between immune response and immune regulatory cells or cytokines.Methods Based on the antibody against hepatitis B surface antigen（HBsAg） after HB vaccination,the CD4＋CD25＋ Tregs frequencies in PBMCs from 18 responders,22 nonresponders and 10 non-immunized healthy controls were analyzed by flow cytometry.The expression of FoxP3 mRNA in PBMCs with or without stimulation of phytohemagglutinin（PHA）and HBsAg was analyzed by real-time quantitative PCR.Levels of IL-4,IL-12,IL-18,and IFN-γ secreted by PBMCs after PHA and HBsAg stimulation were analyzed by enzyme-linked immunosorbent assay.Results The ratio of CD4＋CD25＋ Tregs to CD4＋ T cells in the nonresponders was markedly higher than that in the responders（P0.05）,but lower than that in the controls（P0.01）.FoxP3 was differentially expressed among the responders,nonresponders,and controls in PBMCs before and after PHA and HBsAg stimulation,and nonresponders had the highest FoxP3 mRNA expression（P0.05 or P0.01）.The content of IFN-γ by PBMCs after PHA and HBsAg stimulation was markedly lower in the nonresponders as compared with the controls and responders（P0.05）.However,there were no significant differences in the levels of IL-18,IL-4,and IL-12 from PBMCs after PHA and HBsAg stimulation between the responders and controls as well as the nonresponders（P0.05）.Conclusion CD4＋CD25＋ FoxP3＋ Tregs may be involved in the negative regulation of responses to hepatitis B vaccination.Immunologic non-responses to hepatitis B vaccination may be related to IFN-γ hyposecretion in PBMCs.