间充质干细胞对系统性红斑狼疮CD4+Foxp3+T淋巴细胞的调节

目的 探讨同种异体骨髓间充质干细胞(MSC)体内外对系统性红斑狼疮(SLE)患者外周血CD4+Foxp3+T淋巴细胞及人脐带MSC移植对MRL/lpr鼠脾脏和淋巴结CD4+Foxp3+T淋巴细胞水平的影响.方法 血缘相关供者骨髓中分离培养MSC移植治疗5例SLE患者,采用流式细胞术检测移植前后外周血CD4+Foxp3+T淋巴细胞百分率.7例SLE患者外周血单个核细胞(PBMC)分别与SLE患者和正常人骨髓MSC按不同比例体外共培养72 h,检测共培养后PBMC中CD4+Foxp3+T淋巴细胞百分率.MRL/Ipr鼠输注脐带MSC后检测脾脏和淋巴结CD4+Foxp3+T淋巴细胞百分率.结果 SLE患者异基因骨髓MSC移植后1周外周血CD4+Foxp3+T淋巴细胞百分率(4.8±1.6)%和移植后3个月(6.0±2.6)%均较移植前(2.1±1.2)%明显升高(5例,P<0.05).正常骨髓MSC与SLE患者PBMC共培养后CD4+Foxp3+T淋巴细胞百分率明显升高(P<0.05).且存在剂量依赖性,狼疮MSC也可上调SLE患者CD4+Foxp3+T淋巴细胞水平,但作用较正常MSC弱(P<0.05);正常MSC培养上清也可上调SLE患者PBMC中CD4+Foxp3+T淋巴细胞水平,但作用弱于MSC:PBMC=1:1组(P<0.05).MRL/Ipr鼠经1次或3次脐带MSC移植后脾脏CD4+Foxp3+T淋巴细胞百分率均较对照组高(P<0.05),但淋巴结CD+Foxp3+T淋巴细胞百分率均较对照组低(p<0.01),1次和3次移植组间差异无统计学意义.结论 异基因甚至异种MSC移植可上调SLE患者或MRL/Ipr鼠CD4+Foxp3+T淋巴细胞水平,同时体外试验也得出相同结论,且体外上调作用呈一定剂量依赖性,CD4+Foxp3+T淋巴细胞水平上调可能是MSC移植治疗SLE有效的机制之一.     

失代偿期乙型肝炎肝硬化患者骨髓间充质干细胞对自体外周血淋巴细胞及调节性T细胞亚群增殖的影响

目的研究乙型肝炎肝硬化失代偿期患者骨髓间充质干细胞(BMSCs)对其外周血中淋巴细胞、调节性T细胞亚群(Tregs)增殖的影响。方法 12例乙型肝炎肝硬化失代偿期患者骨髓分离培养出间充质干细胞,采用倒置显微镜观察培养后的贴壁细胞形态、采用流式细胞仪技术观察间充质细胞免疫表型;在植物血凝素(PHA)刺激下、自体血清作为培养基,实施BMSCs和患者自体外周血淋巴细胞共培养,分为A组(BMSCs+淋巴细胞+PHA接触培养)、B组(BMSCs+淋巴细胞+PHA非接触培养)、C组(淋巴细胞+PHA培养)、D组(淋巴细胞),均72 h后观察BMSCs对外周血淋巴细胞增殖及Tregs细胞表达的影响。结果流式细胞仪分析结果显示:培养3代后的间充质干细胞主要高表达T细胞亚群(Tregs)中的CD44(95.26%)、CD29(92.18%),低表达CD34(1.27%)、CD25(1.33%)。C组淋巴细胞增殖率显著高于A、B、D组(P0.05),A、B两组显著高于D组(P0.05),但A、B两组差异无统计学意义(P0.05)。A、B、C组Tregs细胞表达率显著高于D组(P0.05),A、B两组显著高于C组(P0.05),A、B两组差异无统计学意义(P0.05)。结论乙型肝炎肝硬化失代偿期患者BMSCs对其外周血中淋巴细胞增殖具有抑制作用、同时调上调T细胞亚群表达,BMSCs可能具有免疫抑制作用。     

类风湿关节炎骨髓间充质干细胞的体外培养和一般生物学特性的初步研究

目的 建立类风湿关节炎(RA)患者骨髓间充质干细胞(BMSCs)的体外培养、扩增方法,了解其一般生物学特性.方法 采集RA患者的骨髓标本,经密度梯度离心加贴壁法分离、纯化获得其BMSCs,进行体外培养扩增,观察原代和传代细胞的形态和生长状况、免疫表型分析及增殖能力检测,并对BMSCs进行成纤维细胞集落(CFU-F)形成分析.结果 来自RA患者的BMSCs呈典型的成纤维样细胞形态,表型鉴定CIM5阴性,SH2(CD105)、CD71、CD44阳性,其增殖能力和CFU-F形成能力与源于正常供者的BMSCs相当.结论 RA患者骨髓中存在具有多向分化能力的MSCs,来源于RA患者的BMSCs在体外具有良好的细胞增殖能力,在细胞形态、集落形成能力以及细胞免疫表型方面与正常供者的BMSCs差异无统计学意义.     

成纤维滑膜细胞p53基因表达对类风湿关节炎患者CD4+T淋巴细胞的调节

目的 研究人成纤维滑膜细胞(FLS)p53基因表达对类风湿关节炎(RA)患者CD4+T淋巴细胞的调节作用.方法 采用小分子干扰RNA(siRNA)转染抑制FKS内p53基因表达,并与RA患者外周血CD4+T淋巴细胞共同培养.检测转染后FLS中骨保护素(OPG)表达及白细胞介素(IL)-6分泌.并对与之共培养的CD4+细胞膜胞质内蛋白干扰素(IFN)-γ、IL-17、IL-4和CD25以及IFN-γ孤儿核受体γt(RORγt)、IL-17、Foxp3 RNA水平进行测定.结果 p53基因被抑制后,FLS分泌IL-6减少,但OPG表达未受影响.p53基因被抑制的FLS使共培养的CD4+T淋巴细胞内IL-17及IFN-γ蛋白和RNA表达上调,但对CD4+T淋巴细胞RORγt RNA影响不大.虽可上调Foxp3表达,但CD4+CD25high细胞阳性率并无明显变化.结论 FKS内D53表达对RA外周血Th1、Th17有调节作用.     

骨髓源性间充质干细胞联合来氟米特对小鼠T淋巴细胞的免疫调节作用

目的 探讨骨髓源性间充质干细胞(BMSCs)在体外联合来氟米特(LEF)对小鼠T淋巴细胞的免疫调节作用.方法 直接贴壁筛选法分离培养小鼠BMSCs,流式细胞分析(FCM)鉴定BMSCs的纯度.用EZ-SepTMm Mouse 1X分离异体BALB/c小鼠的脾淋巴细胞,在刀豆球蛋白A(ConA)诱导的同时,先经LEF处理,洗去LEF后,脾淋巴细胞再和BMSCs共培养.分组:A组:脾淋巴细胞;B组:脾淋巴细胞+BMSCs;C组:LEF处理的脾淋巴细胞;D组:LEF处理的脾淋巴细胞+BMSCs.用四甲基噻唑蓝(MTT)比色法检测各组T淋巴细胞的增殖情况,流式细胞术分析各组T淋巴细胞的活化及凋亡情况,定量反转录-聚合酶链反应(RT-PCR)检测各组T淋巴细胞的白细胞介素(IL)-2、IL-10基因水平.结果 在体外,BM-SCs处理组(B组)T淋巴细胞的A570 nm值为0.578±0.042,LEF处理组(C组)A570 nm值为0.5024±0.040,两组A570 nm值均显著低于对照组(A组)A570 nm值为0.778±0.035(P<0.01).BMSCs联合LEF组(D组)A570 nm值为0.218±0.033,显著低于BMSCs处理组及LEF处理组(P<0.01). BMSCs联合LEF对CD3+CD69+、CD3+CD28+表达、IL-2基因表达均无明显影响.BMSCs单独或联合LEF组T淋巴细胞凋亡率分别为(2.29±0.32)%、(4.22±0.98)%,较A组T淋巴细胞凋亡率(8.08±1.20)%均明显下降.BMSCs处理组和LEF处理组T淋巴细胞IL-10基因相对表达分别为:0.098±0.039、0.054±0.022明显低于A组(IL-10基因相对表达为1.000)(P<0.01),MSCs联合LEF组IL-10基因相对表达为:0.023±0.015,显著低于BMSCs处理组及LEF处理组(P<0.01).结论 BMSCs联合LEF对小鼠T淋巴细胞有一定程度的协同免疫调节作用.     

异基因骨髓间充质干细胞对类风湿关节炎患者主要细胞因子分泌的影响

目的 探讨在体外环境中,异基因骨髓间充质干细胞( Allo-BM-MSCs)对类风湿关节炎(RA)患者的白细胞介素(IL)-1、肿瘤坏死因子(TNF)-α和转化生长因子(TGF)-β1分泌的影响。方法 采集健康供者的骨髓标本,经密度梯度离心分离、纯化获得其骨髓间充质干细胞(bMSCs),进行体外培养扩增。同时采集RA患者的外周血,分离单个核细胞。将来源于健康供者的bMSCs分别与来源于RA患者的单个核细胞和健康供者的单个核细胞在体外进行共培养,用酶联免疫吸附试验( ELISA)法检测bMSCs与淋巴细胞混合培养液中细胞因子IL-1、TNF-α和TGF-β1的变化。采用方差分析和相关性分析进行统计学分析。结果 经bMSCs与RA淋巴细胞共培养7d后,培养液中IL-1浓度(6.2±1.0) ng/L和TNF-α浓度(4.6± 1.2) ng/L低于单独RA组浓度(38.4±0.5)和(29.4±1.3) ng/L,差异均有统计学意义(P＜0.05);但是单独正常淋巴细胞和bMSCs与正常淋巴细胞共培养后,培养液中IL-1浓度(4.4±l.3)和(4.4±1.1) ng/L及TNF-α浓度(5.3±1.7)和(5.0±1.7) ng/L之间比较差异均无统计学意义（P＞0.05）;经bMSCs与RA淋巴细胞共培养7d后,培养液中TGF-β1浓度(22.5±2.2) ng/L高于单独RA组(2.6± 1.0) ng/L,差异有统计学意义(P＜0.05);单独正常淋巴细胞和bMSCs与正常淋巴细胞共培养后,培养液中TGF-β1浓度(4.8±1.4)和(10.5±1.2) ng/L比较差异有统计学意义(P＜0.05)。IL-1与TNF-α呈正相关（r=0.896,P=0.000）,TGF-β1 与TNF-α呈负相关（r=-0.356,P=0.019）,TGF-β1与IL-1呈负相关（r=-0.380,P=0.000）。结论 AlloBM-MSCs在体外可以特异性调节RA患者细胞因子的分泌。bMSCs可能在RA发病和发展中起一定的作用,有希望用于RA治疗。     

慢性乙型肝炎患者浆样树突状细胞体外诱导CD4+CD25+调节性T细胞的研究

目的 观察慢性乙型肝炎患者,乙型肝炎恢复者和健康人浆样树突状细胞(pDCs)体外诱导CD4+CD25+调节性T细胞(CD4+CD25+Treg)能力的差异,为阐明HBV感染慢性化的机制奠定基础.方法 采用免疫磁珠分离法体外分离46例慢性乙型肝炎患者,10例乙型肝炎恢复者和25名健康人外周血单个核细胞中pDCs,并将其分别与健康人CD4+CD45RA+初始T细胞共培养.采用HBcAg或破伤风毒素对去除CD25+细胞的外周血单个核细胞进行增殖刺激后,使用流式细胞仪及RT-PCR对pDCs-T共培养细胞中CD4+CD25+Treg的数量、表型及FOXP3基因表达情况进行测定;采用酶联免疫吸附法对共培养细胞上清液中的白细胞介素-10和转化生长因子β1进行了进一步检测.两组数据比较采用Mann Whitney U-test.结果 当细胞增殖刺激物为HBcAg时,细胞增殖幅度慢性乙型肝炎患者组为(7999.36±374.74)cpm,乙型肝炎恢复者组为(11 282.56±1174.46)cpm和健康人组为(12 304.58±1462.81)cpm,慢性乙型肝炎患者组细胞增殖幅度明显小于乙型肝炎恢复者组和健康人组,U=0～22.0,P值均<0.05·乙型肝炎恢复者组和健康人组间增殖幅度差异无统计学意义.当增殖刺激物为破伤风毒素时,细胞增殖幅度与阳性对照组之间,差异无统计学意义.CD4+CD25+Treg比例慢性乙型肝炎患者组为5.99%±1.85%,乙型肝炎恢复者组为3.04%±0.79%,健康人组为3.01%±1.53%,慢性乙型肝炎患者组中韵CD4+CD25+Treg比例明显高于乙型肝炎恢复者组和健康人组,U=6.0～71.5,P值均<0.05.3组人群pDCs-T共培养细胞的CD4+CD25+T细胞均检测到Fox p3 RNA,而在CD4+CD25 T细胞中,均未检测到Fox p3RNA.3组人群pDCs-T共培养细胞实验组上清液的白细胞介素-10和转化生长因子β1含量均明显高于阳性对照组.结论 pDCs以诱导CD4+CD25+Treg形式参与了乙型肝炎的慢性化.     

活动期类风湿关节炎患者外周血CD3+T淋巴细胞、NK细胞与IL-6水平的相关研究

目的探讨外周血T淋巴细胞、NK细胞分群在类风湿关节炎(RA)中的意义及与IL-6水平的相关情况。方法流式细胞仪法检测外周血淋巴细胞,记录20例RA患者和15例正常人的类风湿因子、血沉、抗核抗体(ANA)及免疫球蛋白、补体C3水平,ELISA法检测血清IL-6水平,并记录RA患者临床资料。结果活动期RA患者外周血CD3+T细胞计数与对照组分别为(68.8±7.8)、(62.3±4.2),活动期RA患者外周血CD3+T细胞计数轻度增高,但无统计学差异;RA患者外周血NK细胞(CD3-CD56+NK)计数与对照组分别为(9.8±1.8)、(12.3±2.0),RA患者明显低于对照组,P0.05;活动期RA患者IL-6水平高于对照组,分别为(13.8±4.4)ng/L、(4.8+3.0)ng/L,有统计学意义。结论IL-6水平增高、CD3+T细胞和NK细胞表达失衡,其各自免疫调节作用在RA中可能体现不同的效应作用,RA的发病机制中三者间可能具有相互调节的免疫机制。     

沙利度胺对类风湿关节炎T淋巴细胞的免疫调节作用

目的 探讨沙利度胺(Thd)对类风湿关节炎(RA)患者外周血T淋巴细胞的免疫调节作用.方法 在植物血凝素(PHA)刺激下,RA患者外周血T淋巴细胞与不同浓度的Thd(2.5、25、100、300、500μg/ml)共同培养.用四甲基噻唑蓝(MTT)比色法检测T淋巴细胞的增殖,用流式细胞术检测T淋巴细胞的凋亡和T淋巴细胞CD152、CD28的表达情况,用Real-time聚合酶链反应(PCR)检测T淋巴细胞的自细胞介素(IL)-6、IL-10、肿瘤坏死因子(TNF)-α mRNA表达水平.结果 在体外,与阴性对照组相比,500μg/ml,Thd组显著抑制T淋巴细胞的增殖,促进T淋巴细胞早期凋亡,抑制T淋巴细胞CD3+CD28+表达,促进CD8+CD152+表达,而≤300μg/ml,对T淋巴细胞未见明显影响.与对照组相比,(100～500)μg/ml剂量组可抑制T淋巴细胞IL-6、TNF-α mRNA表达,(2.5～500)μg/ml可促进IL-10 mRNA的表达.结论 Thd可能通过影响RA患者外周血T淋巴细胞增殖、早期凋亡、CD3*CD28+和CD8+CD152+表达,以及IL-6、IL-10、TNF-α mRNA表达,反转RA患者的免疫平衡失控.     

HBV相关原发性肝癌患者外周血T、NK、B细胞及胸腺功能特征

目的:观察乙型肝炎相关原发性肝癌患者(hepatitis B virus-related primary liver cancer,H B V-P L C)发生和进展过程中外周血T、N K、B细胞数量的变化,并初步探讨T淋巴细胞减少与胸腺功能的联系.方法:收集在首都医科大学附属北京地坛医院住院的73例HBV-PLC患者,50例乙型肝炎肝硬化患者(liver cirrhosis,LC),37例慢性乙型肝炎(chronic hepatitis B,CHB)患者.收集3组患者一般资料和临床生化指标.采用流式方法检测3组患者外周血中CD3~+T淋巴细胞、CD4~+T、CD8~+T、CD3-CD16~+CD56~+NK、CD3-CD19~+B的分布情况,并检测了T淋巴细胞表面CD31、CD45RA分子的表达水平.结果:与CHB和LC患者相比,HBV-PLC患者外周血中性粒细胞升高,淋巴细胞减少(P0.001);与CHB患者相比,HBV-PLC患者外周血NK细胞计数减少(P=0.011),T淋巴细胞、CD4~+T、C D8~+T、B细胞计数减少,纯真CD4~+和CD8~+T细胞表面CD31表达降低(P0.001).在肝癌Child、Okuda、BCLC分期中晚期比早期淋巴细胞计数、T、CD4~+T、CD8~+T计数均降低(P0.05).结论:随着肝癌的发生和进展,HBV-PLC患者外周血抗肿瘤免疫细胞减少,这种减少与胸腺迁出功能降低有关.     

Mechanisms of CD23 hyperexpression on B cells from patients with rheumatoid arthritis.

OBJECTIVE: To analyze the mechanisms involved in the characteristic hyperexpression of CD23 on peripheral blood B cells from patients with rheumatoid arthritis (RA). METHODS: Peripheral blood mononuclear cells (PBMC) were obtained from patients with active disease and activated during 18 h with an anti-CD3 monoclonal antibody in the presence or absence of blocking antibodies to CD154 or CD40. PBMC were further purified by rosetting and CD23 expression was assessed on B cells by flow cytometry after double staining (CD19/CD23). Lymphocytes were also isolated from synovial fluid (SF). CD154 expression was analyzed on PB or SF CD4+ T cells after double staining (CD4/CD154) by flow cytometry at basal conditions and after different stimuli [anti-CD3 or phorbol myristic acetate (PMA) plus ionomycin]. Co-culture experiments between SF and PB cells were performed to analyze the involvement of the CD40-CD154 interaction on CD23 expression. CD154 and CD23 expression was also analyzed on synovial membrane by immunohistochemical techniques. RESULTS: A high proportion of activated CD23 B cells was detected in patients with RA. Blocking experiments with both anti-CD40 and anti-CD154 Mab showed a significant reduction in the proportion of PB B cells expressing CD23. Following activation with anti-CD3 Mab or PMA plus ionomycin, CD154 expression was mainly induced on PB CD4+ T cells. In co-culture experiments, SF T cells were more efficient than PB T cells in inducing CD40 dependent CD23 expression on PB B cells. In addition, CD4+ T cells from synovial membrane clearly expressed CD154. CONCLUSION: Our results establish a link between CD154-CD40 pathway and CD23 expression on PB B cells from patients with RA. T cells from the synovial microenvironment were active participants in this CD23 expression, presumably in the context of cell recirculation.     

Expression and function of inducible costimulator on peripheral blood T cells in patients with systemic lupus erythematosus

OBJECTIVE: To investigate the role of inducible costimulator (ICOS) in the pathogenesis of SLE, we assessed its expression on peripheral blood CD4 and CD8 T cells and functional roles in patients with systemic lupus erythematosus (SLE). METHODS: Expression of ICOS on peripheral blood CD4 and CD8 T cells and ICOS ligand (ICOSL) on peripheral blood CD19 B cells from patients with SLE, patients with rheumatoid arthritis (RA) and healthy volunteers were determined by two-colour flow cytometry. The functional costimulatory effects of ICOS on peripheral blood mononuclear cells (PBMC) were assessed by T-cell proliferative responses, cytokines, anti-double-stranded DNA (anti-dsDNA) antibody and total IgG production. RESULTS: Peripheral blood CD4 and CD8 T cells expressing ICOS were significantly increased in patients with SLE compared with patients with RA and healthy subjects. Peripheral blood CD19 B cells expressing ICOSL in SLE were markedly reduced compared with RA. Proliferative responses of anti-CD3/ICOS costimulation were significantly higher than those of anti-CD3/hamster IgG (HIgG) in healthy subjects, but not in patients with SLE. Anti-CD3/ICOS-stimulated SLE PBMC secreted similar levels of IL-10 and IFN-gamma but a significantly lower level of IL-2 than healthy PBMC. Anti-CD3/ICOS-mediated costimulation significantly enhanced the production of anti-dsDNA antibodies and total IgG in patients with SLE. CONCLUSION: Hyperexpression of ICOS on peripheral blood CD4 and CD8 T cells from patients with SLE contributed to the dysregulated T-cell proliferation, T-cell activation and pathogenic autoantibody production, which showed that the abnormality of ICOS costimulation may play an immunopathological role(s) in the pathogenesis of SLE.     

The CD69 activation pathway in rheumatoid arthritis synovial fluid t cells

Objective. To study the CD69 activation pathway in synovial fluid (SF) T lymphocytes from patients with rheumatoid arthritis (RA). Methods. Peripheral blood mononuclear cells (PBMC) or SF mononuclear cells (SFMC) were used in proliferation assays with anti-CD69, anti-CD28, anti-CD3, phorbol myristate acetate (PMA), and/or recombinant interleukin-2 (IL-2). CD69+, CD69—, and resting SF T cells were also proliferated. CD25 expression and production of IL-2 after CD69 activation were assessed by flow cytometry and in a bioassay with the IL-2-dependent cell line CTLL-2. Results. RA SFMC did not proliferate either in the presence of anti-CD69 monoclonal antibodies alone or with concomitant PMA activation, when compared with paired or control PBMC. Similar low proliferative responses via the CD3 or CD28 pathway with PMA were observed. This defective proliferation of RA SFMC after stimulation through the CD69 molecule was explained in part by a failure to express CD25 and to produce IL-2. SF CD69- T cells and resting SF T cells had higher rates of proliferation through the alternative costimulatory pathway CD28 than did SF CD69+ T cells or freshly isolated SF T cells. Conclusion. Freshly isolated SF T cells present a profound state of hyporesponsiveness through the CD69 and CD28 costimulatory pathways. This state appears to be dependent on the activation status of SF T cells, since CD69— and resting SF T cells showed recovery of the ability to proliferate through the CD28 activation pathway.     

Functional abnormalities of CD8+ T cells define a unique subset of patients with common variable immunodeficiency

A substantial subgroup of patients with common variable immunodeficiency (CVI) exhibit an abnormal T-cell phenotype characterized by a low CD4/CD8 ratio associated with a significant increase in the absolute number of CD8+ T cells (CVI4/8low patients). In the present study, we examined the phenotypic and functional properties of purified T-cell subsets in this group of CVI patients. CD8+ T cells from CVI4/8low patients manifested increased expression of HLA-DR and CD57 and decreased expression of CD45RA as compared with CD8+ T cells from normal controls. When stimulated with anti-CD3 and phorbol 12-myristate 13-acetate, purified patient CD8+ T cells exhibited significantly decreased proliferation, c-myc expression, and interleukin-2 (IL-2) production compared with that of normal CD8+ T cells. Nevertheless, mitogen-activated patient CD8+ T cells secreted elevated amounts of gamma-interferon and IL-5 and normal amounts of IL- 4. This abnormal pattern of proliferation and cytokine production was limited to the CD8+ T-cell subset as CD4+ T cells from these patients exhibited normal proliferation and cytokine production. In further functional studies, purified CD8+ T cells from CVI4/8low patients manifested increased cytotoxic T-lymphocyte activity and suppressor activity, as compared with normal CD8+ T cells, when they were tested in (1) an anti-CD3 "redirected" cytotoxicity assay and (2) a suppressor assay consisting of CD8+ T cells and Staphylococcus aureus Cowan I (SAC) plus IL-2-stimulated normal (allogeneic) B cells. In the latter case, patient CD8+ T cells suppressed IgG production, but not IgM production. Finally, in studies to evaluate the role of patient CD8+ T cells in the pathogenesis of hypogammaglobulinemia, we determined the capacity of SAC and IL-2 to induce Ig production in highly purified patient B cells, ie, in the absence of patient CD8+ T cells. We found that, whereas B cells from one patient produced normal amounts of IgG, B cells from three patients were unable to produce normal amounts of IgG under these conditions. These data establish the phenotypic and functional characteristics of CD8+ T cells in CVI4/8low and clearly distinguish CVI4/8low patients from other patients with this syndrome. The data do not support the contention that hypogammaglobulinemia in CVI4/8low patients is due to a direct effect of CD8+ T cells on terminal B-cell differentiation, except in the occasional patient. The abnormal CD8+ T cells may, nevertheless, have more subtle effects of lymphoid function that play a role in disease pathogenesis.     

The repertoire of rheumatoid factor–producing b cells in normal subjects and patients with rheumatoid arthritis

Objective. To compare the B cell repertoire of normal individuals and patients with rheumatoid arthritis (RA) and, specifically, to identify precursor B cells with the potential to secrete rheumatoid factor (RF) and to understand the T helper cell requirements for the production of this autoantibody. Methods. Frequencies of precursors of IgM, IgG, and RF-producing B cells were measured in a limiting-dilution system. Two distinct sources of T cell help were compared. T cell help was provided by anti-CD3–activated CD4+ human T cell clones, or T cell–B cell interaction was facilitated by the bacterial superantigen staphylococcal enterotoxin D (SED). Results. A subset of 2–14% of peripheral blood B cells secreted IgM and IgG in SED-driven cultures. The SED-responsive B cell subpopulation was present at 10 times higher frequency in normal donors compared with RA patients. However, the repertoires were very similar, particularly for RF+ precursors, which represented approximately one-third of all SED-responsive B cells. In normal individuals, most of these RF+ precursor B cells did not respond to anti-CD3–activated T helper cells, with only a very small fraction of B cells activated by anti-CD3–driven helper cells maturing into RF-secreting B cells (from 1 of 182 to 1 of 889 IgM-producing B cells). This subset was expanded approximately 50-fold in RA patients. Conclusion. Normal subjects and RA patients share a pool of B cells which secrete RF when activated in the presence of SED and T helper cells. These B cells are frequent and obviously anergic in normal individuals. The B cell subset with the potential to produce RF when help is provided in noncognate T–B interaction (anti-CD3–driven T cells) is considerably expanded in RA patients, probably reflecting an increased responsiveness of such B cells to helper signals.     

CD4+CD25+Foxp3+调节性T细胞在慢性乙型肝炎患者中的作用

目的 探讨CD4+CD25+Foxp3+调节性T细胞与乙型肝炎慢性化和病毒清除之间的关系.方法 收集慢性活动性乙型肝炎(CAH)患者19例、HBV携带者(AsC)21例、HBV感染恢复者12例和健康对照者15例.通过流式细胞术分析外周血CD4+CD25+Foxp3+T细胞的表型和频率,磁珠分选(MACS)CD4+CD25+T细胞,实时荧光定量PCR方法 分析Foxp3 mRNA基因在CD4+CD25+T细胞的表达水平.统计学处理采用单因素方差分析或非参数检验.结果CAH或AsC组外周血CD4+CD25+Foxp3+T细胞频率以及CD4+CD25+T细胞中Foxp3 mRNA的表达水平显著高于健康对照组或HBV感染恢复者(F=6.8,F=3.72,均P<0.05).免疫组织化学染色发现,CAH患者肝组织Foxp3'T细胞浸润累积较对照组明显增高,但AsC较CAH减少.HBeAg阳性患者(包括CAH和AsC)CD4'CD25'T细胞频率显著高于HBeAg阴性患者(t=2.3,P<0.05),抗-HBe阴性患者显著高于抗-HBe阳性患者(t=2.4,P<0.05).CD4+CD25+Foxp3+T细胞频率与慢性乙型肝炎患者血清中HBV病毒载量存在正相关(r=0.56,P<0.01).结论 慢性乙型肝炎患者CD4+CD25+Foxp3+调节性T细胞异常与乙型肝炎慢性化和病毒清除有关.     

CD4+CD25+CD127low/-T淋巴细胞在类风湿关节炎患者外周血中的表达及意义

目的 检测调节性T淋巴细胞新旧标志在活动性类风湿关节炎(RA)患者外周血中的表达,探讨用CD127代替FOXP3对调节性T淋巴细胞进行研究的可能性.方法 选取活动性RA患者32例,其中未经缓解病情抗风湿药(DMARDs)治疗者20例,经DMARDs治疗效果不佳者12例,以25例原发性干燥综合征(pSS)患者和24名健康人作为对照,采用流式细胞术检测外周血中CD4+CD25high、CD4+CD25+CD127low/-及CD4*CD25+FOXP3+T淋巴细胞的比例,同时检测外周血C反应蛋白(CRP)、红细胞沉降率(ESR)、免疫球蛋白、补体等水平并进行相关性分析.结果 RA患者CD4+CD25highT淋巴细胞百分率与健康对照组相比差异无统计学意义(P>0.05).其CD4+CD25+FOXP3+T淋巴细胞与CD+CD25+CD127low/-T淋巴细胞的百分率均低于健康对照组(P<0.05),但CD4+D25+FOXP3+、CD4+CD25+CD127low/-T淋巴细胞在RA患者与pSS患者中的表达差异无统计学意义(P>0.05);这三群细胞的表达水平在RA未经治疗组和治疗效果不佳组之间差异均无统计学意义(P>0.05). RA患者CD4+CD25+FOXP3+T淋巴细胞与CD4+CD25+CD127low/-T淋巴细胞之间呈明显正相关(r=0.698,P=0.001),但这两群细胞与患者的CRP、ESR等水平及抗环瓜氨酸肽(CCP)抗体、类风湿因子(RF)均无相关性(P>0.05).结论 活动性RA患者外周血中,CD4+CD25+CD127low/-T淋巴细胞的百分率降低,并且与CD4+CD25+FOXP3+T淋巴细胞呈显著正相关性,提示CD127可能被作为Treg细胞中FOXP3的替代标记.     

Proinflammatory mediator-induced reversal of CD4+,CD25+ regulatory T cell-mediated suppression in rheumatoid arthritis

OBJECTIVE: We previously demonstrated that CD4+,CD25+ regulatory T (Treg) cells are present in increased numbers in the synovial fluid (SF) of rheumatoid arthritis (RA) patients and display enhanced suppressive activity as compared with their peripheral blood (PB) counterparts. Despite the presence of these immunoregulatory cells in RA, chronic inflammation persists. The purpose of the present study was to investigate whether particular proinflammatory mediators that are associated with RA could abrogate CD4+,CD25+ Treg-mediated suppression. METHODS: Monocyte phenotype was determined by flow cytometry and cytokine levels by enzyme-linked immunosorbent assay. Magnetically sorted CD4+,CD25- and CD4+,CD25+ T cells derived from the PB and SF obtained from RA patients were stimulated alone or in coculture with anti-CD3 monoclonal antibody (mAb) and autologous antigen-presenting cells, in the absence or presence of anti-CD28 mAb or the proinflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor alpha (TNFalpha), or IL-7. RESULTS: Monocytes from the SF of RA patients displayed increased expression of HLA class II molecules, CD80, CD86, and CD40 as compared with PB-derived monocytes, indicating their activated status. Mimicking this increased costimulatory potential, addition of anti-CD28 mAb to cocultures of CD4+,CD25- and CD4+,CD25+ T cells resulted in reduced CD4+,CD25+ Treg-mediated suppression in both PB and SF. Furthermore, IL-7 and, to a limited extent, TNFalpha, both of which are produced by activated monocytes and were detected in SF, abrogated the CD4+,CD25+ Treg-mediated suppression. In contrast, IL-6 did not influence Treg-mediated suppression. CONCLUSION: Our findings suggest that the interaction of CD4+,CD25+ Treg cells with activated monocytes in the joint might lead to diminished suppressive activity of CD4+,CD25+ Treg cells in vivo, thus contributing to the chronic inflammation in RA.     

Th17细胞/调节性T细胞偏倚在类风湿关节炎中的意义

目的 探讨白细胞介素(IL)-17+CD4+炎症性T细胞(Th17细胞)和Foxp3+CD4+调节性T细胞在类风湿关节炎(RA)的相互关系及可能机制.方法 采用前瞻性随机开放研究.测定RA患者外周血IL-17+CD4+T细胞及Foxp3+CD4+T细胞的比例变化及其相关细胞因子转化生长因子(TGF)-β、IL-6、IL-23和IL-17水平.结果 RA患者外周血IL-17+CD4+T细胞明显升高(P<0.01),而Foxp3+CD4+T细胞明显降低(P<0.01).同时,血清中IL-6、IL-23和IL-17水平明显升高(均P<0.01),而TGF-β水平无明显变化(P>0.05).结论 RA患者Th17细胞数量增高,而调节性T细胞数量减少,体内相关细胞因子的变化是引起上述改变的重要原因.