单元型相同骨髓移植后患者单核细胞来源的DC表面分子的检测

对单元型相同骨髓移植患者造血重建后的外周血单个核细胞加GM-CSF、IL-4进行DC诱导,7d后加入TNF-α于培养DC中,继续诱导3d。测定DC的表型、混合淋巴细胞反应对T细胞增殖能力的测定,并与健康志愿者外周血来源的DC进行比较。探讨单元型相同造血干细胞移植后患者单个核细胞来源的DC的生物学特性。结果显示,单元型相同造血干细胞移植患者外周血单个核细胞和正常人外周血单个核细胞来源的DC均高表达CD1α、CD83、CD80、CD86和HLA-DR等DC的相关抗原和共刺激分子,患者的未成熟DC经TNF-α诱导后,成为成熟和有功能的DC,单元型相同造血干细胞移植患者单个核细胞来源的DC在体外具有激发同种异体外周血T细胞增殖的能力,与健康人外周血来源DC组相比均无统计学意义(P>0.05)。     

HBsAg体外冲击的慢性乙肝患者树突状细胞的生物学特性及其对HBV特异性CTL的诱导作用

目的 :研究HBsAg冲击的慢性乙肝患者单核细胞来源的树突状细胞 (DCs)的功能状况及体外对HBV特异性CTL的诱导作用 ,初步探讨诱导特异性抗HBV细胞免疫的途径。方法 :分离慢性乙肝患者外周血单核细胞 ,以GM CSF +IL 4 +TNF α培养诱导DCs,加入HBsAg冲击以诱导HBV特异性DCs。采用FCM测定细胞表面免疫分子CD1a、CD83、CD86、CD80、CD4 0以及HLA DR的表达水平 ,ELISA法检测培养上清中细胞因子IL 6、IL 12的分泌含量 ,MTT法测定DC刺激同种异体淋巴细胞增殖的能力 ,LDH法检测DC诱导的患者外周血T细胞对HepG2 2 2 15 (转染HBVDNA)、HepG2肝癌细胞株及K5 6 2白血病细胞株的细胞毒作用。结果 :HBsAg冲击的DC其表达CD1a、CD83、CD86、CD80、CD4 0、HLA DR表面分子明显高于对照组 (P <0 0 1,P <0 0 5 ) ,分泌IL 12的水平也高于对照组 (P <0 0 1) ,而分泌IL 6的水平则较对照组显著降低(P <0 0 1) ;HBsAg冲击的DC刺激同种异体淋巴细胞增殖的能力明显增强 (P <0 0 5 ) ,并可有效地诱导自体CTL对转HBV基因的HepG2 2 2 15细胞高效特异性杀伤作用 (P <0 0 1)。结论 :慢性乙型肝炎患者单核细胞来源的DCs经HBsAg抗原冲击后 ,生物学活性增强 ,并且能有效地诱导对HBV特异性反应的CTL。     

慢性乙肝患者树突状细胞对Th1/Th2分化的影响

探讨慢性乙肝患者树突状细胞(dendritic cells,DC)对CD4+Th细胞亚群分化的影响。分离慢性乙肝患者外周血单个核细胞(PBMC),以rhIL-4(50 ng/ml)、rhGM-CSF(10 ng/ml)和rhTNF-α(100 u/ml)诱导培养DC。以流式细胞仪检测DC表面CD1a、CD83、CD80、CD86、HLA-DR分子表达情况。MTT法检测DC刺激同种异体淋巴细胞增殖能力。免疫磁珠分离外周血CD4+T细胞亚群,PMA+Ionomycin刺激后胞内荧光染色,流式细胞仪检测辅助性T细胞(helper T cell,Th)内特征性细胞因子IFN-γ/IL-4以判断Th1/Th2分化。ELISA法检测DC或Th细胞培养上清中IL-6、IL-12、IFN-γ和IL-4的含量。结果:慢性乙肝患者的DC表达CD1a、CD83、CD80、CD86、HLA-DR分子水平明显低于正常人(P<0.01);培养至第7天,慢性乙肝患者DC分泌的IL-12水平低于正常人(P<0.01),而分泌的IL-6水平增高(P<0.05)。与正常人相比,慢性乙肝患者外周血中Th1细胞占CD4+T细胞的百分比较低(P<0.01),其Th细胞培养上清中IFN-γ的量也较低(P<0.01)。患者DC与同种异体的健康人Th细胞共培养,刺激Th1型细胞因子IFN-γ产生的能力低于正常人(P<0.01)。慢性乙肝患者体内DC功能的异常可能导致了外周血Th1细胞分化不足。     

少量人外周血体外培养鉴定单核细胞来源树突状细胞方法初探

目的:在少量人外周血条件下体外培养并鉴定单核细胞来源树突状细胞(Monocyte-derived dendritic cells,Mo DC)。方法:取健康成人少量新鲜外周血经改良密度梯度离心法分离获得单核细胞,加入重组人粒-巨噬细胞集落刺激因子(rh GM-CSF)、重组人白细胞介素4(rh IL-4)诱导Mo DC生长,并用肿瘤坏死因子α(TNF-α)刺激成熟,倒置显微镜及扫描电镜观察细胞形态;分别于培养第4天和第7天用流式进行表型鉴定、CCK-8法检测同种异体混合淋巴细胞反应鉴定抗原递呈能力。结果:Mo DC呈类圆形,聚集成团,悬浮生长,扫描电镜观察其表面有典型毛刺状突起;流式检测Mo DC高表达CD11c、CD1a,经TNF-α刺激后的Mo DC表面MHCⅡ、CD80、CD83、CD86表达均较培养4 d的Mo DC明显升高,具有统计学意义(P0.05);经TNF-α刺激后的Mo DC刺激同种异体淋巴细胞增殖能力较培养4 d的Mo DC明显升高,具有统计学意义(P0.05)。结论:用本实验方法可从少量人外周血中获得成熟Mo DC,为其在多种变态反应疾病、自身免疫性疾病及肿瘤疫苗等领域的研究提供基础保障。     

慢性乙型肝炎患者外周血来源树突状细胞的功能状态

通过比较细胞因子诱导的外周血来源的慢性乙型肝炎患者树突状细胞 (DC )和正常人DC在免疫分子表达和免疫功能等方面的差别 ,探讨慢性乙型肝炎患者DC所处的功能状态。以细胞计数、间接荧光表型分析、MTT法测定DC对同种异体淋巴细胞的刺激作用、ELISA法测定DC分泌IL 1 2、IL 6等方法进行研究。实验结果表明 :慢性乙型肝炎患者相同数量的前体细胞经诱导分化形成的DC数量明显减少 ;在培养的 3、 6、 9d,与同期正常人相比 ,慢性乙型肝炎患者的DC表达CD1、CD83、CD80和HLA DR分子水平均较低 ,而CD1 4分子表达水平较高 ;刺激同种异体淋巴细胞增殖能力也低于同期正常人 ;在培养的第 6天DC分泌的上清液中 ,慢性乙型肝炎患者DC分泌的IL 1 2水平低于正常人 ,而分泌的IL 6水平高于正常人。结果提示 ,慢性乙肝患者外周血来源的DC免疫功能处于抑制状态 ,细胞因子表达异常。     

转染自体胃癌细胞总RNA的树突状细胞诱导个体化免疫治疗的体外实验

目的探讨转染自体胃癌细胞总RNA的树突状细胞(DC)体外介导抗胃癌的免疫效应。方法制备短期培养的原代胃癌细胞。用rhGM-CSF、rhIL-4和TNF-α体外诱导胃癌患者外周血单个核细胞(PBMC)中DC的发育和成熟,并转染自体肿瘤细胞总RNA,激活自体T细胞产生CTL,用CCK-8试剂盒检测CTL的杀伤活性。应用流式细胞术及混合淋巴细胞培养技术检测DC的免疫功能状态。用ELISA法测定IL-12和INF-γ的水平。结果转染自体肿瘤细胞总RNA的成熟DC,不仅可高表达MHC-I、II类分子及CD80、CD83和CD86协同刺激分子,并可获得高效刺激自体或异体T细胞增殖的能力。转染RNA的成熟DC,分泌IL-12的水平及其刺激产生的CTL培养上清液中INF-γ的水平显著高于单纯成熟DC及未成熟DC;且CTL对自体胃癌细胞的杀伤率显著高于异体组。结论转染自体胃癌细胞总RNA的成熟DC能够体外诱导产生对自体肿瘤细胞具有高度抗原特异性杀伤活性的CTL。     

亚硒酸钠对慢性乙型肝炎病毒感染者外周血树突状细胞功能的影响

目的 探讨体外培养诱导慢性乙型肝炎患者外周血树突状细胞(DCs)功能状态改善的方法.方法 用GM-CSF IL-4 INF-a诱生慢性乙型肝炎患者及健康人外周血来源的DCs,在乙肝患者DCs成熟前加入营养浓度的硒(0.3mmol/L)共培养.流式细胞仪(FCM)检测细胞表面CD80、CD86表达水平,四甲基偶氮唑盐比色法(MTT法)检测DCs刺激同种异体淋巴细胞增殖能力及酶联免疫吸附测定法(ELISA法)检测DCs培养上清中白细胞介素12(IL-12)的分泌水平.结果 经营养浓度硒(0.3mmol/L)作用后的乙肝患者的DCs刺激淋巴细胞增殖能力明显高于未经硒作用的乙肝组(P<0.01),IL-12的分泌水平和表面刺激分子也明显高于乙肝组(P<0.01),加硒组和健康组之间则没有显著性差异.结论 体外经营养浓度的硒作用后的乙肝患者的DCs可有效刺激淋巴细胞增殖反应,提高IL-12分泌水平,在一定程度上能恢复DCs的免疫功能,这些为今后DCs的慢性乙型肝炎的免疫治疗提供新思路.     

姜黄素诱导的免疫耐受性人树突状细胞的研究

目的:探讨姜黄素(Curcumin)诱导免疫耐受性人树突状细胞(Dendritic cell,DC)的效果。方法:聚蔗糖-泛影葡胺(ficoll-hypaque,F-H)密度梯度离心法获得健康人外周血单个核细胞(PBMC),在含有重组人粒-巨噬细胞集落刺激因子(rhGM-CSF)、重组人白介素4(rhIL-4)的培养基中培养6天。实验共分四组:①未成熟DC组(imDC组)、②姜黄素组(Curcumin,Cur组)、③姜黄素+脂多糖组(Cur+LPS组)、④脂多糖组(LPS组)。流式细胞术检测DC表型CD80、CD86、CD83及HLA-DR的表达情况和DC吞噬葡聚糖的能力,酶联免疫吸附法(ELISA)检测DC分泌白介素-12(IL-12)的能力,混合淋巴细胞反应(MLR)检测DC刺激同种异体T淋巴细胞增殖的能力。结果:Cur能够显著抑制DC共刺激分子CD80、CD86、CD83及HLA-DR的表达,并呈剂量依赖性,与imDC组比较差异无统计学意义;与LPS组比较,Cur+LPS组DC吞噬葡聚糖的阳性细胞百分率显著提高(P<0.05),而刺激同种异体T淋巴细胞增殖的能力则显著下降(P<0.05),IL-12的分泌量也显著下降(P<0.05)。结论:姜黄素能够抑制人树突状细胞的成熟,从而获得免疫耐受性的人树突状细胞。     

钙离子载体在诱导人外周血单核细胞分化为树突状细胞中的作用

目的研究钙离子载体(CI)能否诱导人外周血单核细胞(PBMC)分化为树突状细胞(DC)，并初步探讨其信号转导途径。方法分离健康献血者的PBMC，在体外用CI(A23187)或人重组粒细胞／巨噬细胞集落刺激因子(rhGM—CSF)和CI培养40h，或rhGM-CSF和白细胞介素4(IL-4)培养7d，部分PBMC预先用W-7或CsA或K35926处理30min后，再加入上述细胞因子或CI。相差显微镜下观察细胞形态，流式细胞仪检测细胞表面CD14、CD80、CD86、CD83等分子的表达，MTT比色法检测其对同种异体混合T淋巴细胞的刺激增殖作用。结果健康献血者的PBMC经CI培养40h，或rhGM—CSF与CI培养40h，或rhGM-CSF与IL-4培养7d，均可获得DC的典型形态和表面分子的表达，包括CD14表达下调、共刺激分子(CD80、CD86)表达上调，以及较强刺激同种异体混合T淋巴细胞增殖的作用；CI诱导的DC其CD14分子的下调及CD83分子的上调更明显，刺激混合T淋巴细胞的增殖能力更强；rhGM-CSF可协同CI诱导PBMC向DC的分化。经rhGM—CSF及CI处理的PBMC，其形态、表面标志物及对T细胞的刺激增殖能力，均受到W-7或CsA或KT5926不同程度的抑制；而rhGM-CSF及IL-4所诱导的PBMC其形态、表面分子的表达以及刺激T细胞增殖的作用却不受上述抑制剂的影响。结论CI可快速诱导PBMC向DC分化，其分化过程可能受控于Ca^2 /钙调蛋白及其下游的多个细胞信号转导途径的调节。     

钙动员诱导人外周血单核细胞分化为树突状细胞的信号转导

目的初步探讨钙离子载体（CI）在体外迅速诱导人外周血单核细胞（PBMC）分化为树突状细胞（DC）的信号转导途径。方法分离健康献血者的PBMC,在体外用人重组粒／巨噬细胞集落刺激因子（rhGM-CSF）和CI培养40h或rhGM-CSF和TNF-α培养5d,部分PBMC用环胞菌素A（CsA）预处理30min后,再加入CI或TNF-α;相差显微镜下观察细胞的形态;流式细胞仪检测细胞表面CD14、CD80、CD86、CD83、HLS-DR等分子的表达;MTT比色法检测其对同种异体T淋巴细胞的刺激增殖作用;凝胶电泳迁移率变动分析（EMSA）检测不同方法培养的细胞其核转录因子-κB（NF-κB）的活化水平。结果健康献血者的PBMC经rhGM-CSF与CI培养40h或rhGM-CSF与TNF-α培养5d,均可获得DC的典型形态和表面分子的表达,包括CD14表达下调,CD80、CD86及HLA-DR等分子表达的上调,以及较强刺激同种异体T淋巴细胞增殖的作用;其中CI诱导的DC其CD80、CD86、CD83、HLA-DR等分子的上调更明显,刺激T淋巴细胞的增殖能力更强。经TNF-α及CI所诱导分化的DC均具有较好的NF-κB活性。但经CI诱导的DC,其形态、表面标志物、对T淋巴细胞的刺激增殖能力及NF-κB的活性,均受到CsA的抑制;而TNF-α所诱导的DC却不受CsA的影响。结论CI比TNF-α更迅速、更高效地诱导PBMC向DC分化的原因,是信号转导途径的不同,但不论上游信号转导途径有何不同,两者最终都通过激活NF-κB诱导细胞的分化。     

Enhanced in vitro stimulation of rhesus macaque dendritic cells for activation of SIV-specific T cell responses

The macaque-simian immunodeficiency virus (SIV) system is one of the best animal models available to study the role of dendritic cells (DCs) in transmission and pathogenesis of HIV, as well as to test DC-based vaccine and therapeutic strategies. To better define and optimize this system, the responsiveness of macaque monocyte-derived DCs to a variety of maturation stimuli was examined. Characteristic immunophenotypic and functional DC maturation induced by standard monocyte conditioned medium (MCM) was compared to the activation induced by a panel of stimuli including soluble CD40L, LPS, Poly I:C, PGE₂/TNF, and a cocktail mixture of PGE₂/TNF/IL-1β/IL-6. Immunophenotypic analysis confirmed that all stimuli induced stable up-regulation of CD25, CD40, CD80, CD83, CD86, HLA-DR, DC-LAMP (CD208), and DEC-205 (CD205). In general, macaque DCs exhibited weaker responses to LPS and Poly I:C than human DCs, and soluble CD40L stimulation induced variable expression of CD25. Interestingly, while the endocytic capacity of CD40L-matured cells was down-modulated comparably to DCs matured with MCM or the cocktail, the T cell stimulatory activity was not enhanced to the same extent. The particularly reproducible and potent T cell stimulatory capacity of cocktail-treated DCs correlated with a more homogenous mature DC phenotype, consistently high levels of IL-12 production, and better viability upon reculture compared to DCs activated by other stimuli. Furthermore, cocktail-matured DCs efficiently captured and presented inactivated SIV to SIV-primed T cells in vitro. Thus, the cocktail represents a particularly potent and useful stimulus for the generation of efficacious immunostimulatory macaque DCs.     

Human lung dendritic cells have an immature phenotype with efficient mannose receptors.

Dendritic cells (DC) can be present at distinct stages of differentiation within the immune system. Sallusto and colleagues have recently described an in vitro culture system suitable for analyzing the maturation processes of DC (Sallusto and colleagues, J. Exp. Med. 1994;179:1109-1118). Monocytes cultured for 6 d in the presence of granulocyte macrophage colony-stimulating factor and interleukin-4 develop into immature DC with a high endocytic capacity but a low capacity to stimulate T cells. When challenged by lipopolysaccharide, these cells upregulate costimulatory molecules, express CD83, and become mature DC. CCR1 and CCR5 chemokine receptors are highly expressed on immature DC and downregulated on mature DC. This in vitro system was used to characterize human lung DC. Lung DC were shown to express some characteristics of in vitro immature DC. These are: (1) low expression of the costimulatory molecules CD40, CD80, and CD86; (2) poor expression of the differentiation marker CD83 and no CD1a; and (3) good capacity to incorporate dextran. Lung DC express moderate levels of CCR1 and CCR5. However, lung DC, like in vitro mature DC, express high levels of major histocompatibility complex Class II molecules, show low expression of CD14 and CD64, and are characterized by their high capacity to stimulate allogeneic T cells to proliferate during mixed leukocyte reactions (MLRs). Although lung DC express low levels of CD80 and CD86, the important role of these costimulatory molecules in inducing high MLR was demonstrated by using blocking antibodies. Therefore, while lung DC have overall a phenotype and an endocytic capacity close to in vitro immature DC, they share, like in vitro mature DC, a powerful capacity to stimulate T cells.     

Maturation of dendritic cells for enhanced activation of anti-HIV-1 CD8(+) T cell immunity

Maturation of dendritic cells (DC) to enhance their capacity to activate T cell immunity to HIV-1 is a key step in immunotherapy of HIV-1 infection with DC. We compared maturation of DC derived from HIV-1-uninfected subjects and infected subjects on antiretroviral therapy (ART) or ART na?ve by CD40 ligand (CD40L) and combinations of TLR3 ligand polyinosinic:polycytidylic acid [poly(I:C)] and inflammatory cytokines IFN-gamma, IFN-alpha, IL-1beta, and TNF-alpha. The greatest levels of virus-specific IFN-gamma production by CD8(+) T cells were stimulated by DC treated with CD40L, followed by DC treated with the poly(I:C)-cytokine combination. The highest levels of IL-12p70 were produced by DC treated with CD40L + IFN-gamma, followed by CD40L and the poly(I:C)-cytokine combination. Neutralization of IL-12p70 indicated that it was only partially involved in direct enhancement of antiviral CD8(+) T cell activity. DC stimulation of antiviral CD8(+) T cell reactivity was enhanced by activated CD4(+) T cells at low concentrations but was suppressed at higher CD4(+) T cell concentrations. Maturation of DC with CD40L obviated the need for CD4(+) T cell help and overcame this suppressive activity. Finally, we showed that DC from HIV-1-infected subjects on ART, which were treated with the poly(I:C)-cytokine combination, retained the capacity to produce IL-12p70 and activate anti-HIV-1 CD8(+) T cell responses after restimulation with CD40L, with or without IFN-gamma. Thus, DC from HIV-1-infected subjects can be engineered with CD40L or a poly(I:C)-cytokine combination for enhancing CD8(+) T cell responses to HIV-1, which has potential applications in HIV-1 immunotherapy.     

Immunomodulatory effect of DC/CIK combined with chemotherapy in multiple myeloma and the clinical efficacy

To investigate the clinical efficacy of adoptive immunotherapy using dendritic cells (DC) and cytokine-induced killer (CIK) cells combined with chemotherapy in multiple myeloma. The immunomodulatory effect of the therapy was discussed by detecting the levels of peripheral blood T cell subsets and CD4⁺CD25⁺ regulatory cells (Treg). Fifty MM patients were randomly divided into two groups: 24 cases in the simple chemotherapy group and 26 cases in the combined therapy group (chemotherapy plus DC/CIK immunotherapy). The therapeutic efficacy and the proportions of peripheral blood T cell subsets and Treg cells were compared between the two groups. The cellular immunity indicators were also compared, including IL-2, IFN-γ, IL-4, IL-10, AgNORs ratio and TGF-β. After 3 weeks of treatment, the life quality and clinical efficacy of the combined therapy group were superior to those of the simple chemotherapy group (P<0.05). CD3⁺CD8⁺ ratio, CD4⁺CD25⁺ ratio, CD4⁺CD25⁺/CD4⁺ ratio, CD4⁺CD25⁺FoxP3⁺/CD4⁺CD25⁺ ratio, IL-4, IL-10 and TGF-β levels of the combined therapy group were obviously lower than those of the simple chemotherapy group (P<0.05). The CD3⁺CD4⁺/CD3⁺CD8⁺ ratio, AgNOR ratio, IL-2 and IFN-γ level and positive rate of NKG2D in the combined therapy group were significantly higher than those of the simple chemotherapy group (P<0.05). These results indicated better immunomodulatory effect of the combined therapy. DC/CIK immunotherapy combined with chemotherapy has a good clinical efficacy and prospect for MM, reversing the Th1 to Th2 shift and increasing the anti-tumor capacity of the immune system.     

CCR7在多器官功能障碍综合征小鼠脾脏树突状细胞迁移变化中的作用

目的:探讨CCR7在多器官功能障碍综合征(MODS)脾脏中的表达变化及其对树突状细胞(DC)迁移的影响.方法:用酵母多糖腹腔注射复制小鼠MODS模型,分为正常对照组和实验3～6小时组、24～48小时组、5～7天组及10～12天组.运用免疫组化方法检测CD11c和CD205标记阳性DC在各组小鼠脾脏中分布的变化,用流式细胞术检测CD86/CD11c和CCR7/CD11c标记阳性细胞在脾脏中含量的变化.结果:正常小鼠脾脏DC含量较少,主要分布在脾脏边缘区;在3～6小时组CCR7表达率较正常对照组显著增加,DC含量显著增加、活性增高,并向白髓T细胞区大量迁移;24～48小时组T细胞区中DC含量开始减少,而CCR7表达率升高达到峰值;5～7天组DC与CCR7含量接近正常对照组,边缘区和T细胞区均可见DC分布;10～12天组DC含量再次升高,但多呈不成熟状态,且以边缘区分布为主,CCR7表达率下降.结论:在MODS病程中脾脏DC的含量和分布变化与CCR7的表达率密切相关,CCR7可以作为评估脾脏DC迁移能力及功能活性的重要指标.     

雌激素通过调节MSC分泌细胞因子影响其对DC成熟与功能的抑制

目的:本研究试图检测不同浓度17β雌二醇(F2)存在的情况下人胎肺间充质干细胞(MSC)增殖和表型的变化,并分析这种状态的MSC对树突状细胞(DC)成熟和功能影响及其可能的机制.方法:分离培养人胎肺MSC,加入不同浓度E2,在24小时后对MSC进行细胞计数、测定其增殖和贴壁能力,并用流式细胞仪分析MSC表面标志,RT-PCR测定MSC中细胞因子(IL-6、TGF-β和VEGF)mRNA的表达情况.进一步探讨了E2处理24小时后的MSC对DC成熟和功能的影响.结果:分离得到的MSC纯度达到95%以上;E2影响MSC的增殖和贴壁能力,但不影响MSC表面标记的表达;MSC与DC共培养后DC表面CD86、MHCⅡ和CD80的表达均有所降低,而当DC与经E2预处理过的MSC共培后,DC表面MHCⅡ、CD80和CD86的表达回升;高浓度E2作用MSC 24小时后,MSC表达的TGF-β与对照组相比减少,而IL-6和VEGF与对照组相比增加.结论:E2可能通过调节MSC分泌细胞因子的水平,改变MSC对DC的免疫抑制作用.     

香加皮羽扇豆烷乙酸酯(CPLA)对树突状细胞分化成熟的影响

目的：探讨香加皮羽扇豆烷乙酸酯（CPLA）对人外周血单个核细胞（PBMC）来源的树突状细胞（DC）在体外分化成熟及免疫活性的影响。方法：从人外周血分离单个核细胞，与细胞因子GM—CSF、IL-4共培养，于第5天加入DC的促成熟刺激剂TNF-α（阳性对照组）或CPLA。倒置显微镜和透射电镜下观察DC的形态；应用流式细胞术检测成熟DC的表面标志CD1a、CD83、CD80和CD86的表达情况；用ELISA检测DC培养上清中IL-12和IFN-γ的含量；用MTT法测定DC刺激T细胞增殖的能力。结果：培养10d后，经CPLA刺激的PBMC呈现出典型DC的形态学特征；成熟DC的特征性表面分子CD1a、CD83、CD80和CD86表达水平均明显上调（P〈0．05）；细胞培养上清中IL-12和IFN-γ含量明显增高（P〈0．05）；刺激T细胞增殖的能力明显增强（P〈0．05）。结论：CPLA可诱导PBMC来源的DC分化成熟，并可促进其细胞因子的分泌，增强DC的免疫调节活性。     

Enhanced T-cell activation and T-cell-dependent IL-2 production by CD83+, CD25high, CD43high human monocyte-derived dendritic cells

Although standardized protocols are widely used for the generation of monocyte-derived immunostimulatory dendritic cells (DC(ims)), the inducibility of Th1 cells by DC(ims) may considerably differ. As a measure for the quality of DC(ims) generated from an individual donor at a certain time point, CD83 is used in combination with HLA-DR and CD86 to assess DC maturation. When phenotypically analyzing DC(ims), we identified a subpopulation ( approximately 60%) of CD83+, CD86+, and HLA-DR+ DC(ims) that co-expressed CD25. DC within a given DC(ims) preparation identified by lower expression of CD83 and by selective expression of CD14, however, did not co-express CD25. In order to establish CD25 as an additional maturation marker of DC(ims), we studied the DC phenotype of these cells as well as the DC-dependent T-cell proliferation and T-cell cytokine production profile after co-incubation with sorted CD25(high) and CD25(low) subpopulations of CD83+, HLA-DR+, CD86+ DC(ims). CD25(high) DC(ims) showed significant up-regulation of the DC activation molecule CD43 and induced increased levels of IL-2 secretion in allogeneic T-cells (170.7+/-86.7pg/mL) as compared to T-cells coincubated with CD25(low) DC(ims) (86.6+/-37.6pg/mL) [p=0.0224]. This was reflected by a significantly lower T-cell stimulatory capacity of CD25(low) DC(ims) (84.0% of CD25(high) DC(ims), 1:10 ratio; p=0.014) whereas the T-cell stimulatory capacity of CD25(low) DC(ims) was much higher when compared to IL-10 induced regulatory DC (55.3% of CD25(high) DC(ims); 1:10 ratio). With regard to cancer vaccination protocols, we propose to use CD25 and CD43 as additional markers for DC quality control, assessment of maturational status, and positive selection.     

Generation of functionally mature dendritic cells from elutriated monocytes using polyinosinic : polycytidylic acid and soluble CD40 ligand for clinical application

Despite the increasing use of dendritic cell (DC) vaccination in clinical trials, optimal conditions for the generation of functionally mature DCs remain to be established. The current standard DC maturation protocol for clinical trials has been used as an inflammatory cytokine cocktail [tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, IL-6 and prostaglandin E(2)], but this cocktail induced insufficient maturation of DCs derived from elutriated monocytes when cultured in X-VIVO 15. The aim of this study was to define effective combinations of stimulators for generating functionally mature DCs from elutriated monocytes under current good manufacturing practice conditions. We compared the functional capacity of DCs in response to all possible pairwise combinations of four different classes of stimuli: TNF-alpha, peptidoglycan, polyinosinic : polycytidylic acid [poly(I:C)] and soluble CD40 ligand (CD40L). Maturation status of DCs stimulated with combination of four stimuli was similar to that of the cytokine cocktail as assessed by the cell surface phenotype. However, only the combination of poly(I:C) + CD40L induced complete functional activation of the whole DC population, assessing IL-12p70 production, allostimulatory activity, migratory response to CCL19 and T helper 1-polarizing capacity. Thus, the protocol based on the combination of poly(I:C) and CD40L is more effective for the induction of clinical-grade DCs from elutriated monocytes than the standard cytokine cocktail.     

Defective tumor necrosis factor alpha-induced maturation of monocyte-derived dendritic cells in patients with myelodysplastic syndromes

Myelodysplastic syndromes (MDS) are clonal stem cell disorders, characterized by ineffective and dysplastic hematopoiesis. MDS patients have a defective immune response manifested by increased susceptibility to bacterial infections, autoimmune phenomena, and high incidence of lymphoid malignancies. Presently, we investigated the phenotype and function of monocyte-derived dendritic cells (MoDC) in 23 MDS patients and 15 controls at different stages of differentiation using the maturation stimuli tumor necrosis factor-alpha (TNF-alpha) and LPS. Monocytes from MDS patients showed low potential to differentiate into dendritic cells (DC), as determined by low cell yield and CD1a expression. MDS-MoDCs exhibited low expression of mannose receptor and reduced endocytic capacity. MDS-MoDCs showed a diminished response to TNF-alpha with low CD83, CD80, and CD54 expression and allostimulatory capacity. In patients with 5q syndrome, monocytes and MoDCs were positive for the 5q deletion, suggesting their origin from the malignant clone. Our data indicate that MoDCs in MDS display quantitative and functional abnormalities that may contribute to the defective immune response of these patients.