外周血单核细胞诱导的CD123＋髓系树突状细胞的特性研究

目的:探讨体外髓系培养体系中外周血单核细胞来源的CD123+髓系树突状细胞(mDC)的生物学特性.方法:分离健康人外周血单核细胞,用重组的粒/单核细胞集落刺激因子(GM-CSF)和白细胞介素4(IL-4)将其诱导为树突状细胞(DC).用流式细胞术(FCM)检测DC表面共刺激分子、 CD304 、 CD123和CD11C的表达,并用间接免疫磁珠法将其中CD123+DC加以分离纯化; 激光共聚焦显微镜、扫描电镜观察CD123+DC形态; ELISA法检测CD123+DC的IL-12 分泌量; 葡聚糖吞噬试验和3H-TdR渗入法分别检测CD123+DC的吞噬功能和对同种异体T细胞的刺激能力.结果:外周血单核细胞经GM-CSF和IL-4诱导7 d后,细胞表面高度表达CD86和CD11C,中等量表达CD1a和CD123,低表达CD83,丧失CD14的表达,其中,CD123和CD11C均匀分布于DC表面.免疫磁珠纯化后的CD123+DC呈现典型的不成熟DC形态,除细胞体积较小外,其表面突起类似于CD123-DC.CD123+DC仅微量分泌IL-12,其吞噬能力强于CD123-DC(P<0.05),但抗原刺激功能低于后者(P<0.05).结论:GM-CSF和IL-4培养体系中的CD123+DC可能是DC分化发育过程中更早期的未成熟mDC,具有独特的生物学特性.     

转染HPV16E6基因人树突状细胞疫苗的制备及生物学特性

目的：制备来源于人外周血并转染HPV16E6基因的树突状细胞（DC）疫苗，检测其细胞形态、分子表型及诱导的免疫效应。方法：细胞因子扩增人外周血DC，Lipofectamine转染HPV16E6制备DC疫苗。动态形态学观察，免疫细胞化学及流式细胞术检测分子表达．体外诱导并测定CTL活性。结果：转染DC呈形态迥异的多突起状，其E6蛋白、CD80、CD86和CD83分子的表达率依次为47．3％、82．5％、79．8％和85．7％，诱导杀伤Caski细胞的活性明显高于对照组（P〈0．01）。结论：转染DC疫苗保持了功能成熟DC的形态特征，且内源性表达E6蛋白，能诱导高效的特异性抗肿瘤免疫应答。     

人外周血树突状细胞培养和地塞米松对其分化的影响作用

目的分离培养和鉴定人外周血树突状细胞（DC）,以及探讨地塞米松对其分化的影响作用。方法密度梯度离心法分离人外周血单个核细胞,贴壁后加入GM-CSF、IL-4和LPS培养,部分组另加入地塞米松,观察细胞形态学、流式标志和DC与T淋巴细胞共培养后的增殖变化。结果外周血单核细胞诱导培养后具有DC形态学特征,CD83表达上调,CD14表达下调,DC与T淋巴细胞共培养后呈增殖反应。培养液中加入地塞米松后CD83表达下调,CD14表达上调,DC与T淋巴细胞共培养后增殖反应减弱。结论外周血单核细胞经联合细胞因子可诱导为DC;地塞米松可使DC在功能上处于不成熟状态。     

小鼠肺微血管内皮细胞磁珠分选法分离和原代培养

背景:肺组织的功能依赖于肺微血管内皮细胞的活性,因此肺微血管内皮细胞是相关研究的重要细胞模型,但目前国内多采用的组织块贴壁法培养所得的肺微血管内皮细胞常有其他细胞混杂。目的:建立一种有效分离、培养、扩增小鼠肺微血管内皮细胞的方法。方法:采用酶消化、免疫磁珠二次分选法分离纯化小鼠肺微血管内皮细胞,贴壁培养法体外扩增,CCK-8法测定细胞的生长情况,相差显微镜观察培养细胞的形态,透射电子显微镜观察细胞的超微结构,流式细胞仪对其表型进行鉴定。结果与结论:培养所得小鼠肺微血管内皮细胞具有典型的铺路石样形态学特征,含有大量内皮细胞特有的杆状细胞器Weibel-Palade小体,较稳定地表达内皮细胞特异性表面标记CD105,不表达淋巴管内皮细胞特异性表面标记血管内皮生长因子受体3。说明免疫磁珠二次分选法可成功分离纯化小鼠肺微血管内皮细胞,体外培养所获细胞纯度高、自我更新能力强,并保留了包括构成、表面抗原表达等特性。     

罗勒多糖对树突状细胞表面分子表达的影响

目的：观察罗勒多糖对人外周血单核细胞来源的树突状细胞（Dendritic cell，DC）表面分子表达的影响，探讨其抗肿瘤免疫机制。方法：从正常人外周血分离获得单核细胞，加入含10％胎牛血清、CM-CSF及IL-4的RPMI1640，37℃培养5天，实验组加入罗勒多糖，对照组加入PBS，流式细胞仪检测细胞表面分子的表达。结果：在细胞因子的诱导下，CD14^＋单核细胞逐渐分化为DC，罗勒多糖作用组与对照组DC均表达CD209、CD80、CD83、CD86、CD1a和HLA-DR，与对照组相比，罗勒多糖组DC表面分子CD80和HLA-DR的表达均明显上调。结论：罗勒多糖能够调节DC表面分子CD80和HLA-DR的表达，这可能是罗勒多糖发挥其抗肿瘤免疫的机制之一。     

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。     

单核细胞源性树突状细胞表达淋巴细胞趋化因子mRNA的初步研究

目的:体外诱导、培养单核细胞源性树突状细胞(DC),研究其淋巴细胞趋化因子(lymphotactin,Lptn)mRNA表达的动态变化。方法:采用密度梯度离心的方法分离人外周血中的单个核细胞(PBMC),用重组人粒细胞-巨噬细胞集落群体刺激因子(rhGM-CSF)、重组人白细胞介素-4(rhIL-4)刺激贴壁的单核细胞,诱导培养DC,第6天用重组人肿瘤坏死因子-α(rhTNF-α)诱导DC成熟。用流式细胞术检测成熟和未成熟的DC表面分子CD1a和CD83;在电镜下观察成熟DC的形态;以RT-PCR法扩增其LptncDNA并克隆至pGM-TEasyT载体中,测序;以RT-PCR结合凝胶成像分析系统,半定量分析培养3、5及7dDC的LptnmRNA表达的强度。结果:电镜观察培养7d的细胞具有典型的DC形态,流式细胞术检测DC表面分子CD83呈高水平表达。用RT-PCR法克隆的cDNA序列与GenBank中U23772(登陆号)提供的序列一致。培养3d的DC不表达LptnmRNA,培养7d的DC较培养5d的DCLptnmRNA表达增强。结论:单核细胞源性DC能表达LptnmRNA,随着DC的成熟,LptnmRNA的表达增强。     

γδT细胞的扩增及其信号转导分子ζ链相关蛋白-70的免疫印迹检测

目的 检测人外周血γδT细胞的信号转导分子ζ链相关蛋白-70 （ZAP-70）的表达.方法 应用淋巴细胞分离液常规分离获取健康人外周血单个核细胞（PBMC）,用结核杆菌低分子多肽抗原（Mtb-Ag）刺激PBMC增殖培养,10d后收集细胞,用免疫磁珠阳性分选法分离获取高纯度的γδT细胞;采用免疫印迹方法检测γδT细胞内的ZAP-70分子.结果 新鲜分离的PBMC中γδT细胞的比例仅为4.9％,Mtb-Ag刺激培养10d后升为69.2％,免疫磁珠阳性分选后达99.3％.免疫印迹显示检测到γδT细胞内相对分子质量为70 000的ZAP-70分子的表达.结论 ZAP-70分子在活化增殖的人外周血γδT细胞内高表达.     

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。     

慢性乙型肝炎患者树突状细胞形态、表型和功能的变化

目的 观察慢性乙型肝炎病毒（hepatitis B virus,HBV)感染者树突状细胞（dendritic cells,DC)形态、表型和功能的改变。方法 从13例慢性乙肝患者和11例健康人外周血中分离和培养DC,观察DC的形态。用流式细胞仪检测DC的表面标志,HLA－DR、CD1a,CD80和CD86的表达。用^3H-TdR掺入法,检测DC诱导混合性淋巴细胞反应（mixed leukocytes reaction,MLR)的能力。结果 正常人的DC较慢乙肝患者的DC在形态上更为典型。前者的DC不规则,细胞可表达较多的HLA－DR、CD80和CD86分子（P＜0．05）,诱导MLR的能力也较强（P＜0．05）。结论 慢乙肝患者外周血DC处于不完全成熟状态,其免疫刺激能力较低。     

未成熟树突状细胞快速分离与体外诱导培养及其鉴定研究

目的:以人外周血来源的单核细胞为前体细胞,建立体外快速分离和诱导培养未成熟树突状细胞(Immature dendritic cell,iDC)的方法。方法:采用Ficoll 密度梯度离心方法和MACS 磁珠分选系统,收集高纯度CD14+ 单核细胞;用rhGM-CSF、rhIL-4 联合诱导培养CD14+单核细胞,第4 天获得未成熟树突状细胞(iDC),应用流式细胞术检测细胞表面标记(CCR5)和抗原吞噬能力,普通光学显微镜、扫描电镜和透射电镜观察细胞表面和内部结构特征。结果:CD14 免疫磁珠技术获得CD14+单核细胞纯度达94%以上,诱导分化第4 天的iDC 具有CCR5 特征性标志和吞噬能力,普通光学显微镜及电镜观察到iDC 出现树突状细胞典型特征。结论:体外快速诱导培养是获得大量具有典型特征的iDC 的有效方法,并可应用于进一步实验研究。     

食管黏膜树突状细胞表型分析

目的:研究食管黏膜树突状细胞(DCs)表型特点。方法:内镜下收集健康人食管黏膜标本,Ficoll-Hypaque密度梯度离心法分离食管黏膜标本中的单个核细胞,采用磁珠分选技术分离DCs,流式细胞仪分析食管黏膜DCs表型。结果:健康人食管黏膜含3类单个核细胞:HLA-DRhigh/CD13low,HLA-DRmed/CD13+和HLA-DR-/CD13+;HLA-DRhigh/CD13low细胞表达不同DCs亚群表面标志,是食管黏膜DCs;健康人食管黏膜DCsCD80、CD83、CD86表达水平低,是不成熟DCs。结论:成功分离了食管黏膜DCs,证实HLA-DRhigh/CD13low细胞是食管黏膜DCs。     

Isolation and characterization of dendritic cells from common marmosets for preclinical cell therapy studies

Dendritic cells (DCs) have important functions as modulators of immune responses, and their ability to activate T cells is of great value in cancer immunotherapy. The isolation of DCs from the peripheral blood of rhesus and African green monkeys has been reported, but the immune system in the common marmoset remains poorly characterized, although it offers many potential advantages for preclinical studies. In the present study, we devised methods, based on techniques developed for mouse and human DC preparation, for isolating DCs from three major tissue sources in the common marmoset: bone marrow (BM), spleen and peripheral blood. Each set of separated cells was analysed using the cell surface DC-associated markers CD11c, CD80, CD83, CD86 and human leucocyte antigen (HLA)-DR, all of which are antibodies against human antigens, and the cells were further characterized both functionally and morphologically as antigen-presenting cells. BM proved to be an excellent cell source for the isolation of DCs intended for preclinical studies on cell therapy, for which large quantities of cells are required. In the BM-derived CD11c(+) cell population, cells exhibiting the characteristic features of DCs were enriched, with the typical DC morphology and the abilities to undergo endocytosis, to secrete interleukin (IL)-12, and to stimulate Xenogenic T cells. Moreover, BM-derived DCs produced the neurotrophic factor NT-3, which is also found in murine splenic DCs. These results suggest that BM-derived DCs from the common marmoset may be useful for biological analysis and for preclinical studies on cell therapy for central nervous system diseases and cancer.     

尼克酰胺、β-细胞调节素、bFGF、HGF联合诱导人脐血CD34+细胞向胰岛素分泌细胞的分化

目的 探讨在体外培养条件下用尼克酰胺、β-细胞调节素(betacellulin)、bFGF、HGF诱导人脐血CD34 细胞向胰岛细胞的分化.方法 用磁性细胞分选试剂盒(MACS)分离出CD34 细胞后在含5?S,1×ITS,4.7mg/L亚油酸,10-4mol/L 2-磷酸抗坏血酸的低糖型DMEM中培养,扩增后于培养第5d加入尼克酰胺、betacellulin、bFGF、HGF进行诱导,并于诱导14d、24d留取细胞.应用RT-PCR、免疫细胞化学染色方法检测分化细胞中胰岛细胞标志物,并用ELISA方法检测培养液中胰岛素水平.结果 流式细胞仪检测结果显示,CD34 细胞的平均分离纯度＞90%,达到分离要求.RT-PCR检测到诱导后的CD34 细胞表达nestin、ngn3、IPF-1 mRNA.免疫细胞化学染色可见诱导的CD34 细胞中出现nestin和insulin阳性表达细胞.胰岛素分泌细胞的分化率平均为(9.8±2.7)%.ELISA检测发现诱导组和未诱导组培养液中的insulin含量有显著性差异(P＜0.01).结论 体外联合应用上述因子能诱发脐血CD34 造血干细胞向胰岛素分泌细胞的分化.     

胃癌患者PBMCs中CD4+CD25+T细胞体外增殖及对CD4+CD25-T细胞增殖的影响

目的:探讨胃癌患者外周血单个核细胞（PBMCs）中的CD4+CD25+T细胞体外增殖及对CD4+CD25-T细胞增殖的影响。 方法:以免疫磁性分离方法 （MACS）分选出胃癌患者外周血单个核细胞中的CD4+CD25+T及CD4+CD25-T细胞后，用流式细胞仪分析细胞的纯度及活力；再以小鼠抗人CD3单抗、小鼠抗人CD28单抗及rh IL-2作为共刺激因子，观察与CD4+CD25-T细胞共培养时，CD4+CD25+T细胞对CD4+CD25-T细胞增殖的抑制效应。 结果:（1）分选后健康对照组及胃癌患者PBMC 中CD4+CD25+ T细胞纯度分别为83.8%±1.84%、84.13%±2.77％，两者相比，无显著差异（P＞0.05）;(2)经MACS 分选后正常对照组与胃癌患者CD4+CD25+ T细胞活力分别为98.52%±0.72%、97.80%±0.95%，两者相比，无显著差异（P＞0.05）；(3)无论是健康对照还是胃癌患者的CD4+CD25+T均具有明显抑制效应性T细胞如CD4+CD25-T细胞的增殖，随着CD4+CD25+T细胞数的增加，这种抑制增殖的能力也相应增加，当CD4+CD25+∶〖KG-*2〗CD4+CD25-T达 1∶〖KG-*2〗1时，抑制率最大达到50％。 结论:MACS分选法能够分选出高纯度及活力的CD4+CD25+T细胞，分选后CD4+CD25+T细胞在体外均能抑制CD4+CD25-T细胞增殖，且这种抑制效应呈一定效靶比关系。     

Flow cytometric analysis of T cell proliferation in a mixed lymphocyte reaction with dendritic cells

BACKGROUND: Dendritic cells (DCs) are the most potent antigen-presenting cells. They can be generated in vitro from CD14+ cells, and also from CD34+ progenitor cells. Although T cell proliferation using [3H] thymidine incorporation assay has been used widely to check DC function, this technique only provides limited information about the T cell proliferation. Here, we describe a novel method for quantitative analysis of T cell proliferation using flow cytometry. MATERIALS AND METHODS: DCs were generated from CD14+ cells from six healthy blood donors. Monocytes were isolated using positive selection with magnetic cell sorting (MACS) and then cultured with IL-4, GM-CSF, IL-1beta, IL-6, TNF-alpha and PGE(2) to yield fully mature DCs. Allogeneic naive T lymphocytes with known mismatches in HLA classes I and II were cocultured with DCs. Naive T cells without DC stimulation served as negative controls. T cells were harvested on days 0, 3, 5, 7, 9, 11 and analysed by flow cytometry. CD3-ECD and CD4-fluorescein isothiocyanate (FITC) or CD8-FITC antibodies were used to distinguish T cell subsets, whereas T cell activation was measured by assessment of HLA-DR, CD45RO, CD25 and CD71 expression. For T cell quantification, fluorescent microparticles were used. Dead cells were excluded with 7-AAD. The bromdeoxyridine (BrdU)-incorporation ELISA procedure was also performed in order to compare with the T cell proliferation assay with regard to absolute cell counts and CD71 expression. RESULTS: The initial T cell concentration on day 1 was 203.9+/-39.7 (173-265) CD3+/CD4+ cells/micro l and 184.5+/-41.6 (148-260) CD3+/CD8+ cells/micro l. The maximal T cell proliferation was recorded on day 7 with a five- to tenfold T cell expansion which resulted in 1994.9+/-383 (1446-2404) CD3+/CD4+ cells/micro l and 944+/-303.7 (560-1483) CD3+/CD8+ cells/micro l. Furthermore, activation markers of both cell lineages were upregulated and reached maxima on days 7 (CD71) and 9 (CD25, HLA-DR). T cell count/micro l as well as CD71 expression both correlated significantly with BrdU incorporation. CONCLUSION: Flow cytometric analysis permits simple, precise and rapid quantification of T cell proliferation in a mixed lymphocyte reaction with DCs. Activation, proliferation and cell viability can be simultaneously determined. CD71 is particularly well suited as an activation marker for the simultaneous measurement of T cell proliferation. Thus, specific T cell subsets involved in antigen-specific proliferation can be evaluated in detail.     

Predominance of Th2-promoting dendritic cells in early human pregnancy decidua

Dendritic cells (DCs) are specialized antigen-presenting cells required for the priming and activation of T cells and promote the differentiation of na?ve CD4+ T cells toward the T helper cell type 1 (Th1) or Th2 phenotype. Here, we describe the characterization of CD45+CD3-CD14-CD16-CD19-CD20-CD56-HLA-DRbright DCs from early human pregnancy decidua by flow cytometry. The percentage of DCs to mononuclear cells (leukocytes) in the decidua was significantly higher than that in the peripheral blood. Moreover, decidual DCs expressed costimulatory molecules such as CD80 and CD86 and a mature marker such as CD83 on their surface. The percentage of CD11c+CD123- myeloid DCs in the decidua was significantly higher than that in the peripheral blood. Conversely, the ratio of CD11c-CD123+ lymphoid DCs in the decidua was significantly lower than that in the peripheral blood. The number of interleukin (IL)-12-producing cells in the total DC population and the myeloid DCs in the decidua was significantly lower than that in the peripheral blood. IL-12 secretion by activated decidual myeloid DCs was significantly lower than that by peripheral DCs. Na?ve CD4+ T cells primed with decidual myeloid DCs led to a higher percentage of Th2 cells in comparison with that with peripheral myeloid DCs. This finding was abolished by exogenous IL-12 administration with decidual myeloid DCs. Thus, the DCs in the decidua could regulate the Th1/Th2 balance to maintain a Th2-dominant state, leading to maintenance of pregnancy.     

热处理淋巴瘤细胞增强树突状细胞介导的抗瘤效应研究

目的:探讨淋巴瘤细胞热处理后作为抗原,冲击树突状细胞而引发的抗淋巴瘤免疫效应。方法:用健康人外周血分离出单核细胞,体外培养树突状细胞(Dendritic cells,DCs),将淋巴瘤细胞株热处理(42℃,2小时)培养24小时后负载于DCs,在流式细胞仪上检测DCs的免疫表型变化;负载抗原后的DCs与淋巴细胞混合反应,以MTT法评价细胞毒性及在流式细胞仪上检测淋巴细胞的免疫表型;ELISPOT法检测细胞内因子IFNγ-的释放。结果:在两实验组中,DCs负载了热处理的淋巴瘤抗原后,细胞表面的共刺激分子和MHCⅡ类分子表达水平较对照组明显增加(P0.05),而两组之间差别无显著性(P0.05);经热处理的肿瘤细胞负载于DCs后,与淋巴细胞混合后IFNγ-的释放量明显增加;混合淋巴细胞反应后,细胞毒性实验(MTT法)和流式细胞仪检测结果均显示两实验组的杀瘤作用强于对照组(P0.05),两组之间无显著差别(P0.05)。结论:用热处理的淋巴瘤细胞作为肿瘤抗原冲击DC,能够增强抗淋巴瘤效应。