慢性乙型肝炎患者MoDCs表面PD-L1分子的表达及其对T淋巴细胞功能的影响  

The expression of PD-L1 on monocyte derived dendritic cells and its effect on immune function of T lymphocytes in patients with chronic hepatitis B

作　　者：杨帆[1] 潘修成[2] 陈明[2] 郭忠胜[2] 李丽[2] 冯霞[2] 张言超[2] 

机构地区：[1]解放军第264医院感染病科 [2]徐州医学院附属医院感染病科,徐州市221002

出　　处：《中华实验和临床感染病杂志（电子版）》2012年第4期8-12,共5页Chinese Journal of Experimental and Clinical Infectious Diseases(Electronic Edition)

基　　金：徐州市科委科研基金(No.XM08C079);江苏省重点学科建设基金(No.苏教研【2006】4号

摘　　要：目的探讨慢性乙型肝炎(CHB)患者外周血单核细胞来源的树突状细胞(MoDCs)表面PD-L1的表达水平及其对MoDCs诱导的HBV特异性T淋巴细胞功能的影响。方法采用流式细胞术检测CHB患者、慢性乙型肝炎病毒携带者(ASC组)、健康对照者(NC组)外周血MoDCs表面PD-L1的表达,采用全自动生化分析仪检测ALT(正常参考值<40U/L)和荧光定量聚合酶链反应测定HBVDNA水平。替比夫定抗病毒治疗前后分别体外培养CHB患者的MoDCs。流式细胞术检测MoDCs表面PD-L1表达的变化;负载HBsAg的MoDCs和异体T淋巴细胞混合培养,以PD-L1单克隆抗体阻断PD-L1/PD-1途径后,MTT法检测HBV特异性T淋巴细胞增殖能力;酶联免疫吸附试验(ELISA)测定混合淋巴细胞反应(MLR)上清液中IL-12、IFN-γ和IL-10的浓度。结果 CHB患者外周血MoDC表面PD-L1的表达高于ASC组和NC组,且与患者ALT、HBVDNA水平呈正相关。随抗病毒时间的延长,MoDCs表面PD-L1水平下降,但差异无统计学意义(P>0.05)。封闭PD-L1途径后,MoDCs诱导的T淋巴细胞的增殖能力及MLR中IL-12、IFN-γ水平均升高,IL-10水平降低的程度大于相应的未封闭PD-L1途径组。结论 CHB患者外周血MoDCs表面PD-L1表达水平的升高,降低了HBV特异性T淋巴细胞免疫功能;替比夫定抗病毒治疗对MoDCs表面PD-L1的表达无显著影响;阻断PD-L1/PD-1途径能够提高MoDCs诱导的HBV特异性T淋巴细胞免疫反应。Objective To investigate the expression of PD-L1 on monocyte derived dendritic cells （MoDCs） and its effect on immune function of HBV-specific T lymphocytes in patients with chronic hepatitis B. Methods The levels of PD-L1 on MoDCs in CHB patients, asymptomatic carrier （ASC） and health controls were detected by fluorescence activated cell sorter （FACS）. Before and during telbivudine treatment, MoDCs generated from peripheral blood mononuclear cells （PBMC） were cultured in vitro. The expression of PD-L1 was detected by flow cytometry simultaneously. Followed by mature MoDCs cocuhured with xenogenic T cells, in presence or absence of anti-PD-L1 monoclone, MTT assay was applied to determine the proliferation of HBV-specific xenogenic T cells and enzyme-linked immunosorbent assay （ELISA） was applied to test the concentrations of IL-12, IFN-γ and IL-10 in the supernatants of mixed lymphocytes reaction （MLR）. Results PD-L1 expression was up-regulated on MoDCs in CHB patients, compared to that of ASC and control groups （P 〈 0.05 ）. The level of PD-L1 was positively correlated with serum ALT and HBV DNA. During antiviral treatment, the level of PD-L1 decreased, but with no significant changes （ P 〉0. 05 ）. Blocking of PD-L1 signaling with anti-PD-L1 monoclone enhanced the proliferation of MoDCs mediated xenogenic T cells and the levels of IL-12 and IFN-γ, but the level of IL-10 reduced. Conclusions Increasing PD-L1 on MoDCs could decrease the immune function of T cell in patients with CHB. The effect of telbivudine treatment on the level of PD-L1 on MoDCs is not significant. Blockage of the PD-L1 pathway may enhance the MoDCs mediating HBV specific T cells immune function.

关 键 词：髓样树突状细胞 T淋巴细胞 肝炎 乙型 慢性 替比夫定 

分 类 号：R512.62[医药卫生—内科学]