IL-27促进外周血单个核细胞来源树突状细胞分化成熟

目的:研究IL-27体外对人外周血单个核细胞(PBMC)的来源树突状细胞(DC)分化、成熟及其免疫活性的影响。方法:采集健康成人外周血,密度梯度离心法获得PB-MC,给予GM-CSF、IL-4诱导DC,第5天后根据不同处理因素将DC分为3组:IL-27组、TNF-α组和阴性对照组。倒置显微镜和透射电镜下观察DC形态;流式细胞术(FCM)检测DC表面分子CD1a、CD80、CD83和CD86的表达情况;MTT法检测DC刺激T细胞增殖的能力。结果:IL-27刺激后PB-MC来源DC呈现典型的成熟DC形态学特征。IL-27组DC表面CD1a、CD80、CD83和CD86表达水平较对阴性对照组均明显上调(P<0.05),与TNF-α组DC相比无显著差异。IL-27组DC诱导T细胞增殖的能力较对照组DC明显增高(P<0.05)。结论:IL-27可刺激PBMC来源DC的成熟。     

树突状细胞分化成熟障碍在肿瘤免疫逃逸中的研究

大量研究证实,肿瘤病人体内存在广泛的免疫逃逸现象。目前所知肿瘤逃逸的机制很多,其中重要的一个就是树突状细胞的分化成熟异常导致的功能障碍。近来国内外研究发现许多因素能够影响肿瘤内树突状细胞的正常分化成熟和功能,这些因素包括一些免疫抑制性细胞因子（TGF-β,IL-10,IL-6,VEGF）,神经节苷脂,吲哚咹-2-3加双氧酶等等。     

树突状细胞和HBV感染的研究进展

树突状细胞(Dendritic Cell,DC)是一类专职抗原提呈细胞(Antigen-presenting Cell,APC),目前认为DC与机体抗乙型肝炎病毒(Hepatitis B Virus,HBV)免疫和HBV感染后慢性化的作用机制相关,DC易影响HBV并且细胞内HBV的存在与DC功能缺陷有关,这在HBV慢性化中起到重要作用.现将DC的特点,及HBV与DC之间相互影响及作用机制作一综述.     

JAK/STAT信号转导通路在树突状细胞分化成熟过程中的作用

树突状细胞(DC)是目前发现的效能最高的专职性抗原提呈细胞,其分化成熟过程对机体免疫功能的发挥起着至关重要的作用.大量研究表明JAK/STAT信号转导通路与DC分化成熟密切相关.JAK/STAT是一种多效联级的信号转导通路,是大量细胞因子和生长因子传递信号的主要途径,参与细胞生长发育繁殖凋亡等过程的调节.多种肿瘤病人体内DC分化成熟障碍可能与JAK/STAT通路的异常表达有关.     

雷帕霉素和地塞米松对小鼠树突状细胞分化成熟的调控

目的：观察雷帕霉素（rapamycin，Rap）和地塞米松（dexamethasone，Dex）对堵养的小鼠骨髓来源的树突状细胞（DC）分化发育的影响。方法：（1）用GM-CSF＋IL-4定向诱导C57BL／6小鼠骨髓细胞分化为DC，分别加入Rap或Dex，然后用脂多糖（LPS）刺激。在倒置显微镜和扫描电镜下，动态观察DC形态学E的变化。（2）通过流式细胞术（荧光抗体双标记法）测定CD11c^＋细胞的比例及CD86和MHC-Ⅱ类分子表达的变化。（3）通过单向混合淋巴细胞反应（MLR）观察，Rap和Dex处理的DC刺激BALB／c小鼠同种异基因T细胞增殖的情况。结果：（1）经Rap和Dex处理后，DC在形态学上呈现稳定不成熟状态。（2）Rap处理的细胞表面CDIlc和MHC-Ⅱ类分子的表达仅有轻度降低，而CD86的表达明显降低。Dex处理的细胞表面CDIlc的表达与Dex的剂量呈负相关，CD86和MHC-Ⅱ类分子的表达均明硅降低。两种药物处理的DC均可抵抗LPS的促成熟作用。（3）MLR的结果显示，Rap和Dex处理的DC刺激同种异基因BALB／c小鼠T细胞增殖的能力均较低。结论：Rap和Dex均可使DC处于稳定的不成熟状态。与Dex相比，Rap对骨髓造血F细胞向DC分化的过程影响较小，而且在抑制DC表面协同刺激分子CD86表达的同时，对MHC-Ⅱ类分子的表达影响较小。     

人外周血单核细胞来源树突状细胞的成熟诱导

目的：探讨诱导树突状细胞成熟的最优方法。方法：以细胞因子GM-CSF和IL-4体外诱导人单核细胞来源的树突状细胞，分别采用CD40L、LPS、TNF-α、细胞因子鸡尾酒法（TNF-α、IL-6、IL-1β、PGE2）诱导成熟，24小时后收获DCs以流式细胞仪检测其成熟表型CD80、CD83、CD86、HLA-DR和FITC-Dextran的内吞能力，ELISA法检测其IL-12的分泌，MTT法检测其刺激淋巴细胞增殖活性。结果：CD40L、LPS、TNF-α、鸡尾酒法均可诱导DCs的成熟，其中以鸡尾酒法诱导成熟的效果最优，CD83的表达率为66.91%（P〈0.05）；成熟DCsFITC-Dextran的内吞能力明显下降；成熟DCsIL-12分泌量明显高于未成熟DCs，其中鸡尾酒法诱导成熟的DCs的IL-12分泌量最高，成熟的DCs有较强的刺激淋巴细胞增殖能力。结论：细胞因子鸡尾酒法是诱导DCs成熟的最佳方法。     

碳纳米管对树突状细胞成熟和T细胞分化作用研究

Th分化在免疫应答过程中起着关键性的作用,主要由树突状细胞来调控。碳纳米管是由碳元素组成的空心管状纳米材料,可作为抗原载体。碳纳米管对树突状细胞和Th分化的影响是决定其免疫响应的关键因素。分析氧化多壁碳纳米管(CNT)对小鼠骨髓来源的树突状细胞(BMDCs)功能的影响,以及对过敏抗原多肽OVA_323-339的 Th1和Th2免疫反应的影响。实验结果显示,BMDCs大量吞噬CNT,但对其细胞表面活化标志分子CD86、MHCII以及细胞因子TNF-α表达没有明显变化。CNT/抗原复合物可促进BMDCs表面MHCII的表达和CD8⁺T细胞增殖,增殖细胞的比例由28.7%分别增加到40.6%、41.3%和29.6%。Th2型细胞因子IL-4、IL-13和IL-10的表达和CD4⁺T的增殖受到抑制,增殖细胞的比例由54.4%减少到38.9%、46.6%和39.8%。研究结果提示,CNT不影响DCs的成熟和活化,但CNT可以影响过敏抗原的Th分化平衡,可抑制Th2型细胞因子的表达,促进Th1型免疫响应。     

雷公藤内酯醇对人树突状细胞分化成熟的抑制

雷公藤内酯醇是雷公藤提取物中生物活性最强的物质。其免疫抑制功能主要是通过抑制T细胞的活性，包括抑制T细胞的激活和细胞因子的基因转录以及一些转录因子和信号转导通路调节因子的表达等。本研究以人单核细胞衍生的树突状细胞（monocyte-derived dendritic cells，moDC）为研究对象，探讨雷公藤内酯醇对DC的体外分化和成熟过程的影响。     

Gp130分子的活化在树突状细胞分化和成熟中的意义

目的 :研究激发型抗gp130分子单抗B S12对树突状细胞 (DC)分化成熟和功能的影响。方法 :人外周血单核细胞在GM CSF和IL 4作用下分化为未成熟DC后 ,加入B S12单抗 ,观察它对DC表型、摄取抗原的能力以及DC分泌IL 12、进行混合淋巴细胞反应及趋化T细胞能力的影响 ;同时比较B S12和激发型抗CD4 0单抗 5C11对DC的作用。结果 :激发型抗gp130分子单抗B S12作用于未成熟DC ,可以上调DC上CD1a和共刺激分子CD80、CD86以及成熟DC的标志CD83分子的表达 ,下调CD14的表达 ,降低DC摄取抗原的能力 ,增强DC分泌IL 12、进行混合淋巴细胞反应及趋化T细胞的能力 ,但这些作用都稍弱于 5C11对DC的作用。结论 :未成熟DC上gp130分子的直接活化可以诱导DC的分化和功能成熟。     

浆细胞样树突状细胞与实体肿瘤免疫逃逸

浆细胞样树突状细胞(pDC)以快速分泌Ⅰ型IFN、抑制病毒及细菌等病原入侵的固有免疫应答著称.同时,pDC作为一种专职抗原提呈细胞,能呈递抗原,参与适应性免疫应答.近年来越来越多的研究证明,其分布于实体肿瘤组织内,呈递肿瘤抗原,参与免疫调节,导致肿瘤免疫逃逸.     

MBL对树突状细胞体外分化成熟的影响

目的: 探讨甘露聚糖结合凝集素 (MBL)对人外周血单核细胞来源的树突状细胞 (MoDC)分化成熟的影响。方法: 以天然人MBL刺激MoDC, 在倒置显微镜下观察DC的形态; 用FACS分析DC的表型; 用 3H- TdR掺入法测定DC刺激同种异体T细胞增殖的能力; 以酵母多糖颗粒吞噬试验评估DC的抗原摄取能力; 用ELISA检测DC培养上清中IL- 12和TNF- α的含量。结果: MBL刺激的DC表面分子CD1a、CD83、CD40、CD80、CD86和MHC DR的表达均上调,摄取酵母多糖颗粒的能力降低, 激发初始T细胞增殖的能力加强, 分泌的IL- 12增多但几乎不分泌TNF- α。结论: MBL能诱导DC分化成熟, 提示其可能通过调节DC的功能而参与获得性免疫应答。     

Origin and differentiation of dendritic cells

Despite extensive, recent research on the development of dendritic cells (DCs), their origin is a controversial issue in immunology, with important implications regarding their use in cancer immunotherapy. Although, under defined experimental conditions, DCs can be generated from myeloid or lymphoid precursors, the differentiation pathways that generate DCs in vivo remain unknown largely. Indeed, experimental results suggest that the in vivo differentiation of a particular DC subpopulation could be unrelated to its possible experimental generation. Nevertheless, the analysis of DC differentiation by in vivo and in vitro experimental systems could provide important insights into the control of the physiological development of DCs and constitutes the basis of a model of common DC differentiation that we propose.     

The current immune function of hepatic dendritic cells

While only a small percentage of the liver as dendritic cells, they play a major role in the regulation of liver immunity. Four major types of dendritic cell subsets include myeloid CD8α^-B220^-, lymphoid CD8α^＋B220^-, plasmacytoid CD8α^-B220^＋, and natural killer dendritic cell with CD8α^-B220^-NK1.1^＋ phenotype. Although these subsets have slightly different characteristics, they are all poor naive T cell stimulators. In exchange for their reduced capacity for allostimulation, hepatic DCs are equipped with an enhanced ability to secrete cytokines in response to TLR stimulation. In addition, they have increased level of phagocytosis. Both of these traits suggest hepatic DC as part of the innate immune system. With such a high rate of exposure to the dietary and commensal antigens, it is important for the hepatic DCs to have an enhanced innate response while maintaining a tolerogenic state to avoid chronic inflammation. Only upon secondary infectivity does the hepatic DC activate memory T cells for rapid eradication of recurring pathogen. On the other hand, overly tolerogenic characteristics of hepatic DC may be responsible for the increase prevalence of autoimmunity or liver malignancies.     

The effect of human immunodeficiency virus-1 on monocyte-derived dendritic cell maturation and function

Dendritic cells (DC) are mediators of the adaptive immune response responsible for antigen presentation to naive T cells in secondary lymph organs. Human immunodeficiency virus (HIV-1) has been reported to inhibit the maturation of DC, but a clear link between maturation and function has not been elucidated. To understand further the effects of HIV-1 on DC maturation and function, we expanded upon previous investigations and assessed the effects of HIV-1 infection on the expression of surface molecules, carbohydrate endocytosis, antigen presentation and lipopolysaccharide (LPS) responsiveness over the course of maturation. In vitro infection with HIV-1 resulted in an increase in the expression of DC-specific intercellular adhesion molecule-3-grabbing non-integrin (DC-SIGN) as well as decreases in maturation-induced CCR7 and major histocompatibility complex (MHC)-II expression. Retention of endocytosis that normally occurs with DC maturation as well as inhibition of antigen presentation to CD8(+) T cells was also observed. Mitogen-activated protein kinase (MAPK) responsiveness to LPS as measured by phosphorylation of p38, c-Jun N-terminal kinase (JNK) and extracellular-regulated kinase (ERK)1/2 was not affected by HIV-1 infection. In summary, in-vitro HIV-1 impairs DC maturation, as defined by cell surface protein expression, with selective alterations in mature DC function. Understanding the mechanisms of DC dysfunction in HIV infection will provide further insight into HIV immune pathogenesis.     

钙离子载体诱导HL-60细胞分化成树突状细胞的实验研究

目的 :探讨一种钙离子载体 (calciumionophore,CI)A2 3187,能否诱导早幼粒白血病细胞株HL 6 0分化成具有活性的树突状细胞 (dendriticcells,DCs)。方法 :将生长状态良好的HL 6 0细胞分别加在普通培养液中 ,或在含不同浓度 (2 5～ 16 0 0 μg/L)的A2 3187及 10 0 μg/L重组人粒 /单集落刺激因子 (rhGM CSF)的普通培养液中培养。 2 4～ 96h后 ,在光镜及电镜下观察细胞的形态 ;用流式细胞仪检测细胞的表面标志 ,MTT比色法检测其刺激同种异体T细胞增殖的作用。结果 :HL 6 0细胞以适量 (2 0 0 μg/L)的A2 3187诱导 2 4h ,DC的特征性表面标志CD83分子的表达最高 ,72h可出现典型的树突状突起 ,96h细胞表面CD80 (B7.1)、CD86 (B7.2 )、MHC II分子及细胞间黏附分子CD5 4的表达最高 ,且能明显激活同种异体T细胞。结论 :钙离子载体A2 3187可将HL 6 0细胞诱导成具有活性的DC样细胞。     

青藤碱促进树突状细胞分化抑制其成熟

目的 探讨青藤碱对树突状细胞(Dendritic cell,DC)体外分化发育、成熟、抗原递呈及刺激T细胞活化能力的影响.方法 DC体外培养时,青藤碱处理,观察细胞生长情况,流式检测细胞表型及抗原内吞能力,混合淋巴细胞反应检测DC刺激T细胞活化的能力,E(I)ISA检测细胞因子分泌.结果 与对照组相比,青藤碱处理DCCD1a表达上调而CD14下调,IL-12分泌减少,共刺激分子表达减少,同种T细胞刺激活性降低.结论 合适剂量的青藤碱能刺激单核细胞分化为不成熟DC但能抑制其进一步成熟.     

The role of a nuclear protein, histone H1, on signalling pathways for the maturation of dendritic cells

We have demonstrated previously that liver allograft tolerance is associated with the immunosuppressive activity of anti-histone H1 autoreactive antibodies induced in the serum of liver transplantation. Furthermore, we and others have shown that nuclear proteins such as histone H1 and high mobility group box 1 play an important role in maturation of dendritic cells (DCs), although the precise mechanisms are still unknown. In the present study, we focus upon the significance of histone H1 on DCs in terms of the intracellular signalling pathway of DCs. Our immunostaining and immunoblot studies demonstrated that histone H1 was detected in cytoplasm and culture supernatants upon the activation of DCs. Histone H1 blockage by anti-histone H1 antibody down-regulated the intracellular activation of mitogen-activated protein kinases (MAPKs) (p38) and IkappaBalpha of DCs, and inhibited DC activity in the proliferation of CD4+ T cells. On the other hand, the addition of histone H1 without endotoxin stimulation up-regulated major histocompatibility complex class II, the CD80 and CD86 surface markers of DCs and the activation of MAPKs (p38 and extracellular-regulated kinase 1/2) and IkappaBalpha. These results suggest that the translocation of histone H1 from nuclei to cytoplasm and the release of their own histone H1 are necessary for the maturation of DCs and the activation for T lymphocytes.     

gp130-linked signal transduction promotes the differentiation and maturation of dendritic cells

In order to explore the role of gp130-linked signal transduction in the differentiation and maturation of dendritic cells (DC), the mAb, B-S12, an agonist of gp130, was used for the activation of gp130 on DC. The effects of cytokines and of anti-gp130 mAb on the proliferation of DC, and their expression of IL-12 and CD80 (B7-1) by DC were evaluated. DC differentiating from peripheral blood mononuclear cells did not express the IL-6 receptor alpha chain, but expressed gp130. Anti-gp130 mAb promoted the proliferation of DC, induced by IL-4 and granulocyte macrophage colony stimulating factor (GM-CSF), by up-regulating the GM-CSF receptor on DC. DC induced by gp130 mAb and cytokines expressed DC-derived CC chemokine, as measured by RT-PCR. Induced DC also stimulated strong proliferation of autologous T cells in mixed lymphocyte reaction since an up-regulated expression of IL-12 and CD80 (B7-1) was observed in DC activated by anti-gp130 mAb. Thus, gp130 signal transduction is important for the differentiation and maturation of DC.     

肺癌DC融合细胞诱导的抗肿瘤免疫应答

目的 研究肺癌DC融合细胞FLD－A11体内外诱导免疫应答的能力,方法 用MTT法测定FLD－A11细胞诱导淋巴细胞增殖的能力;ELISA法检测其诱导淋巴细胞分泌IL－2的水平;LDH释放法测定FLD－A11细胞免疫后小鼠脾淋巴细胞的特异性CTL活性。结果 FLD－A11有有效刺激淋巴细胞的增殖反应（SC：RC＝1：50时,SI＝2.38）,诱导淋巴细胞分泌IL－2。FLD－A11细胞免疫后,小鼠的胸腺和脾脏重量均高于对照组（P＜0.05）,脾淋巴细胞对Lewis肺癌细胞的杀伤活性显著高于对照组。结论 FLD－A11细胞具有诱导初次抗肿瘤免疫应答的能力,不仅能在体外诱导淋巴细胞的增殖和IL－2的分泌,而且体内免疫接种也能引起小鼠免疫器官的增生反应,产生针对Lewis肺癌的特异性CTL杀伤作用。