慢性乙型肝炎患者外周血调节性T细胞对树突状细胞功能的抑制作用  

Immunosuppression effects of CD4+CD25+regulatory T cells on dendritic cells from patients with chronic hepatitis B

作　　者：周培培[1] 颜学兵[2] 徐娟[2] 武桂萍[2] 石银月[2] 赵爽[3] 

机构地区：[1]新泰市人民医院,新泰市271200 [2]徐州医学院附属医院感染病科 [3]无锡市第四人民医院消化科

出　　处：《中华实验和临床感染病杂志（电子版）》2013年第3期66-70,共5页Chinese Journal of Experimental and Clinical Infectious Diseases(Electronic Edition)

基　　金：2011年江苏省"科教兴卫"医学重点人才培养基金(No.RC2011117);2011年江苏省"六大人才高峰"项目;2011年江苏省"333高层次人才培养工程"第三层次培养对象

摘　　要：目的研究慢性乙型肝炎(CHB)患者外周血CD4+CD25+调节性T细胞(Treg)对树突状细胞(DCs)免疫功能的抑制作用,探讨治疗CHB的新方法。方法采用密度梯度离心法获得CHB患者和健康对照组(NC组)外周血单个核细胞(PBMC);部分PBMC体外诱导培养获得DCs,部分PBMCs用特异性免疫磁珠分选获得CD4+CD25+Treg和CD4+CD25-T细胞;不同来源的DCs和正常对照组CD4+CD25-T细胞混合为反应细胞,将不同来源和不同比例的Treg分别加入到反应细胞中培养3 d,MTT法检测Treg抑制DCs的抑制指数(SI),并在培养DCs的不同时间加入Treg,应用流式细胞术检测DCs表面共刺激分子CD80和HLA-DR的表达。结果来源于CHB患者及NC组的Treg均可抑制DCs的免疫作用,来源于CHB患者Treg抑制DCs能力显著高于NC,差异具有统计学意义(P<0.01)。不同比例的Treg均可抑制DCs的免疫功能,随着Treg比例的增高抑制作用也越明显,抑制指数亦越高。在DCs培养的不同时间加入相同比例的Treg,发现Treg对DCs表面分子CD80、HLA-DR的表达均有抑制作用,与对照组相比,差异具有统计学意义(P<0.01),同时发现加入Treg的时间越早,DCs表面分子表达降低越明显。结论 CHB患者Treg可显著抑制DCs免疫功能且呈时间和量的依赖,抑制DCs表面分子CD80和HLA-DR表达,可能是Treg抑制DC免疫功能的机制之一。Objective To investigate the suppression of regulatory T cells （Treg） on dendritic cells （DCs） in the pathogenesis of chronic hepatitis B （CHB）, and to find out new method for CHB treatment. Methods Total of 15 cases with CHB and 15 healthy persons were enrolled in the study. Peripheral blood mononuclear cells （PBMCs） were isolated from patients with CHB and normal controls （NC） with density gradient centrifugation. DCs generated from peripheral blood mononuclear cells were cultured and induced by GM-CSF, IL-4 and TNF-a in vitro. Magnetic activatied cell sorting （MACS） was applied to purify Treg and CD4＋CD25- T cell from PBMCs. Mature DCs were mixed with CD4＋CD25- T cell and cocultured with Treg derived from different sources and with different proportionalities for 3 days. MTT assay was used to determine the suppressing index. Treg were added to DCs at different culture stages. Costimulatory molecules CD80 and HLA-DR on DCs surface were analyzed by flow cytometry, respectively. Results Treg from CHB patients and NC suppressed DCs immunity. And treg from patients with CHB suppressed DCs much stronger than that from NC （P 〈 0.01）. DCs were cultured with Treg at different proportions in three days. Thesuppressing rate and index of Treg on DCs immunocapacity both increased with Treg proportion increasing. The expression level of CD80 and HLA-DR in DCs decreased, when adding Treg to the culture system at different times. Earlier addition of Treg, lower expression levels of CD80 and HLA-DR were observed. Conclusions Treg from patients with CHB had stronger suppressing capacity on DCs immunocapacity than those from NC, which was time and dose dependent. Expression decreasing of DCs surface marker of CD80 and HLA-DR may be the possible .

关 键 词：肝炎 乙型 慢性 CD4+CD25+ 调节性T细胞 树突状细胞 

分 类 号：R512.62[医药卫生—内科学]