流产模型孕鼠脾脏调节性T细胞分离纯化方法的初步建立

目的探索流产模型孕鼠CD4＋CD25＋T细胞和CD4＋CD25-T细胞快速高效的分选方法。方法采用免疫磁珠两步法分离流产模型孕鼠脾脏中T细胞,分离后的细胞经台盼蓝染色检测细胞存活率,经流式细胞仪检测分离的纯度。结果流产模型孕鼠脾脏细胞经过免疫磁珠细胞分选法2次分选得到CD4＋/CD25＋调节性T细胞纯度为（93.5±1.1）%,CD4＋/CD25-T细胞纯度为（96.6±0.6）%。结论采用免疫磁珠细胞分选法能够快速高效的得到高纯度的CD4＋CD25＋T细胞和CD4＋CD25-T细胞。     

大鼠CD4+ CD25+ T调节细胞的分离培养及其功能分析

目的:研究大鼠CD4 CD25 T调节细胞(Tr)的分离培养,并对其功能进行初步分析。方法:无菌条件下切取大鼠脾脏分离脾淋巴细胞。用免疫磁珠细胞分离系统(MACS)分选CD4 CD25 T细胞,并以流式细胞术检测其纯度后,对其进行扩增。采用混合淋巴细胞反应研究CD4 CD25 Tr细胞对CD4 CD25-T细胞的免疫抑制作用。用ELISA法检测培养上清中IL-2、IFN-γ及IL-10水平的差异。结果:MACS分离的CD4 CD25 T细胞的纯度达86%~93%。该细胞与CD4 CD25-T细胞相比能特异性地表达Foxp3基因。体外培养中能明显抑制效应T细胞增殖及其分泌IFN-γ、IL-2,但其自身能分泌Th2型细胞因子IL-10。结论:采用MACS系统阴性加阳性分选,可高效快速的获得理想纯度和免疫抑制功能的大鼠CD4 CD25 T调节细胞,该细胞对CD4 CD25-T细胞具有明显的免疫抑制作用,并能特异性的表达Foxp3基因。     

免疫磁珠两步法分离小鼠脾脏CD4+CD25+调节性T细胞

体外分离CD4+CD25+调节性T细胞(CD4+CD25+Treg)并进行初步鉴定.用磁性细胞分离器(MiniMACS)分离CD4+CD25+Treg细胞,流式细胞术(flow cytometry,FCM)分析细胞纯度和Foxp3蛋白表达,体外检测细胞因子.MACS分离的CD4+CD25+Treg细胞纯度大于90%,细胞存活率大于93%,并且特异性表达Foxp3蛋白,体外能抑制CD4+CD25-Treg分泌IFN-γ,同时CD4+CD25+Treg能分泌抑制性细胞因子TGF-β1、IL-10.结果显示,通过MACS可分离高纯度、高活性的CD4+CD25+Treg细胞.     

大鼠CD4+CD25-T细胞的Foxp3基因转染及其表达***◆

背景：调节性T细胞在维持机体免疫应答稳态和免疫耐受方面具有非常重要的作用,但外周血中CD4+CD25+调节性T细胞含量极低,且增殖能力较差。 目的：以携带Foxp3基因的慢病毒EGFP+载体转染大鼠CD4+CD25- T细胞,观察其在大鼠CD4+CD25- T细胞中的表达。 方法：以免疫磁珠两步法分选大鼠CD4+CD25- T细胞,用携带大鼠Foxp3基因的慢病毒载体体外转染分选的细胞,以转染Foxp3基因的CD4+CD25- T细胞为实验组,EGFP空白质粒组及CD4+CD25- T细胞为阴性对照组,CD4+CD25+ T细胞为阳性对照组。荧光显微镜和RT-PCR分别从蛋白和mRNA水平检测Foxp3基因的表达。 结果与结论：成功完成了免疫磁珠的分选,获得了纯度较高的CD4+CD25-T细胞和CD4+CD25+ T细胞,细胞存活率为(94±2)%,慢病毒转染的CD4+CD25- T细胞高表达Foxp3基因。表明以携带Foxp3基因的慢病毒载体系统可有效介导Foxp3基因在大鼠CD4+CD25- T细胞中高表达。     

免疫磁珠负性分离纯化小鼠脾脏CD8+ T细胞

目的 探讨小鼠脾脏CD8 T细胞的免疫磁珠负性分选方法,并对分选后所得细胞进行纯度、活力及功能检测.方法 以免疫磁珠负性分选法从小鼠脾脏细胞中分离CD8 T细胞,流式细胞术检测所得细胞的纯度,台盼蓝检测细胞活力并用ConA刺激检测增殖能力. 结果 经过流式细胞仪测定免疫磁珠负性分选后的小鼠脾脏CD8 T细胞纯度达到(91.6±3.6)%,台盼兰染色细胞活力为(94.9±3.2)%,ConA刺激72 h后有(56.3±1.7)%的细胞增殖.结论 免疫磁珠负性分选法能够分选出高纯度的CD8 T细胞,并且不影响分选靶细胞的细胞活力和功能.     

ConA刺激对CD4~+CD25~+调节性T细胞趋化特性及其表面趋化因子受体CCR4/CCR6表达的影响

目的体外动态观察ConA激活的调节性T细胞表面趋化因子受体的表达变化及其趋化特性,为利用调节性T细胞诱导免疫耐受提供线索。方法常规分离正常健康人外周血单个核细胞,免疫磁珠阴性分选CD4+T细胞;加FITC-An-tiCD4抗体,APC-AntiCD25抗体,PE-AntiCD127抗体上流式细胞仪分选出CD4hiCD127loCD25hi-int细胞。纯化的调节性T细胞与CD4+CD25-T分别用ConA(10μg/mL)刺激0、24、48h后,用趋化因子CCL1、CCL5、CCL20、CCL22做趋化实验,观察各趋化因子作用下调节性T细胞与CD4+CD25-T细胞的趋化特性。同时,流式细胞仪检测CCR4与CCR6的表达。结果分离得到的调节性T细胞纯度为97.4%,活细胞率为95%,得率:4.1%。CCL1、CCL20、CCL22均可趋化调节性T细胞,且在ConA激活后趋化效率随时间而改变。CCL1与CCL22对调节性T细胞的趋化指数显著高于CD4+CD25-T细胞;CCL20对调节性T细胞和CD4+CD25-T细胞趋化指数都很高;CCL5对调节性T细胞趋化性则显著弱于CD4+CD25-T细胞。ConA刺激后...     

Neuropilin-1+T细胞与CD4+CD25+调节性T细胞的比较

目的:分析Neuropilin-1 T细胞(Nrp-1 T细胞)与经典CD4 CD25 调节性T细胞(Treg)的关系并比较二者的免疫调节作用。方法:流式细胞术分析BALB/c小鼠脾脏T细胞上Nrp-1与CD4、CD25的表达关系并分选Nrp-1 T细胞及CD4 CD25 Treg,通过B16-F10-luc-G5黑色素肿瘤细胞体外培养实验并利用萤光成像系统,观察比较两种细胞对NK细胞杀伤B16-F10-luc-G5黑色素瘤细胞的影响。结果:CD4 CD25 Treg中表达Nrp-1的比例为(27.28±1.17)%,明显高于CD4 CD25-T细胞的(1.63±0.08)%(P<0.01);在体外实验中,Nrp-1 T细胞与CD4 CD25 Treg均能抑制NK细胞杀伤B16-F10-luc-G5黑色素瘤细胞,Nrp-1 T细胞组的肿瘤细胞数目在6、24、48、72h分别为984±15、1015±14、1261±21、1323±38,高于CD4 CD25 Treg组的931±4、983±8、1201±18、1256±18,两组肿瘤细胞数目在各时间点均有统计学意义(P<0.01)。结论:经典CD4 CD25 Treg中表达Nrp-1的细胞比例较高,Nrp-1 T细胞有负性免疫调节作用,抑制功能比CD4 CD25 Treg更强,可以作为一类新的Treg亚群。     

猪CD4+CD25+treg细胞系的建立与功能分析

目的 分析猪淋巴细胞表型,分离猪CD4 CD25 T调节性T细胞系并鉴定其免疫生物学特性.方法用磁珠双阳性分选的方法从健康猪外周血及脾脏淋巴细胞中得到CD4 CD25 T细胞CD4 CD25-T细胞,监测其foxp3的表达,并对其进行体外长期培养、扩增,混合淋巴细胞培养实验分析其免疫抑制功能,流式细胞法分析其表型变化.结果猪CD4 CD25 T细胞与人类和啮齿类动物一样,是具有免疫抑制功能的调节性T细胞系.该T细胞系foxp3基因同样高表达,且能抑制同基因CD4 CD25-T细胞的活化,大剂量IL-2可以逆转其抑制功能,扩增培养的猪CD4 CD25 T细胞和诱导扩增的CD4 CD25-T细胞均具有免疫抑制功能.结论 猪CD4 CD25 T细胞为调节性T细胞,具有免疫抑制功能.     

中国健康人外周血中具有CD4+CD25nt/hiCD127lo特征的调节性T细胞频率

目的:初步确定健康人外周血中具有CD4+CD25nt/hiCD127lo特征的调节性T细胞(Treg)频率,为临床相关疾病的研究及Treg的分选提供参考.方法:采集312名8～60岁(5个年龄组)、不同性别健康人的静脉血,经三重免疫荧光染色,用流式细胞术分析CD4+CD25nt/hiCD127lo Treg细胞频率,并观察细胞内Foxp3转录因子的表达.结果:健康人CD4+CD25nt/hiCD127lo Treg细胞在外周血中约占CD4+T细胞的(6.55±0.11)%,各年龄组之间有差异(P=0.015),组内性别之间也存在统计学意义(P＜0.05);CD25nt/hiCD127lo细胞特异性地表达Foxp3转录因子.结论:初步确定了中国健康人外周血中具有CD4+CD25nt/hiCD127lo表达特征的细胞频率,为Treg细胞的临床研究奠定了基础;CD25nt/hiCD127lo作为CD4+CD25+Treg细胞表面的特征性标志,可在分选时排除其他细胞干扰,获得较完整的Treg细胞.     

CD4+CD25+调节性T细胞在自身免疫性疾病中的研究进展

调节性T细胞(regulation T cells,简称Treg)是不同于Th1和Th2的具有调节功能的T细胞群体,在多种免疫性疾病中起重要调节作用.根据其表面标记、分泌的细胞因子及其作用机制不同,Treg可分为CD4 CD25 调节性T细胞(CD4 CD25 Treg)、Tr1和Tr3等多种亚型.     

慢性肝脏疾病中CD3^-CD161^＋NK和CD3^＋CD161^＋NKT细胞亚群的变化研究

目的探讨CD3^-CD161^＋NK、CD3^＋CD161^＋NKT细胞在慢性肝炎／肝硬化及肝细胞癌患者肝脏组织及外周血中表达及意义。方法利用流式细胞仪对31例肝细胞癌患者、59例慢性肝炎／肝硬化患者肝脏组织及外周血、15例正常肝脏组织、48例正常人外周血中的CD3^-CD161^＋NK和CD3^＋CD161^＋NKT进行定量分析。结果慢性肝炎／肝硬化组CD3^-CD161^＋NK细胞[（13．4±1．3）％]和肝细胞癌癌周组CD3^-CD161^＋NK细胞[（16．7±4．8）％]及远离肝癌组的肝脏组织CD3^-CD161^＋NK细胞[（22．0±4．4）％]与正常肝脏组织CD3^＋CD161^＋NK细胞[（35．1±7．2）％]相比,肝细胞癌癌周肝脏组织内含量最低（t值分别为2．301、2．137、2．034,P〈0．05）;外周血中肝细胞癌组CD3^-CD161^＋NK细胞f（11．6±6．3％）]、CD3^＋CD161^＋NKT细胞[（14．7±6．2）％]与慢性肝炎／肝硬化组CD3^-CD161^＋NK细胞[（10．8±1．7）％]、CD3^＋CD161^＋NKT细胞[（12．5±0．8）％]、正常对照组CD3^＋CD161^＋NK细胞[（7．5±0．8）％]、CD3^-CD161^＋NKT细胞[（13．8±1．7）％]相比肝癌组CD3^-CD161^＋NKT细胞含量最高（t值分别为2．134,2．099,P〈0．05）,肝癌组CD3^＋CD161^＋NKT细胞含量最高（t值分别为2．125,2．154,P〈0．05）。结论由于NK细胞及NKT细胞数量减少或／和活性降低,使肿瘤细胞逃逸了免疫监视,可能促进了肿瘤的发生、发展及转移。     

CD40 ligand-positive CD8+ T cell clones allow B cell growth and differentiation

A fraction of activated CD8⁺ T cells expresses CD40 ligand (CD40L), a molecule that plays a key role in T cell-dependent B cell stimulation. CD8⁺ T cell clones were examined for CD40L expression and for their capacity to allow the growth and differentiation of B cells, upon activation with immobilized anti-CD3. According to CD40L expression, CD8⁺ clones could be grouped into three subsets. CD8⁺ T cell clones expressing high levels of CD40L (≥80% CD40L⁺ cells) were equivalent to CD4⁺ T cell clones with regard to induction of tonsil B cell proliferation and immunoglobulin (Ig) production, provided the combination of interleukin (IL)-2 and IL-10 was added to cultures. CD8⁺ T cell clones, with intermediate levels of CD40L expression (10 to 30% CD40L⁺ cells), also stimulated B cell proliferation and Ig secretion with IL-2 and IL-10. B cell responses induced by these CD8⁺ T cell clones were neutralized by blocking monoclonal antibodies specific for either CD40L or CD40. By contrast, CD40L^?? T cell clones (?5 % CD40L⁺ cells), only induced marginal B cell responses even with IL-2 and IL-10. All three clone types were able to activate B cells as shown by up-regulation of CD25, CD80 and CD86 expression. A neutralizing anti-CD40L antibody indicated that T cell-dependent B cell activation was only partly dependent on CD40-CD40L interaction. These CD40L^?? clones had no inhibitory effects on B cell proliferation induced by CD40L-expressing CD8⁺ T cell clones. Taken together, these results indicate that CD8⁺ T cells can induce B cell growth and differentiation in a CD40L-CD40-dependent fashion.     

CD3-induced apoptosis of CD4+CD8+ thymocytes in the absence of clonotypic T cell antigen receptor

Clonal selection of T cells mediated through the T cell antigen receptor (TCR) mostly occurs at the CD4⁺CD8⁺ double positive thymocyte stage. Immature CD4⁺CD8⁺ thymocytes expressing self-reactive TCR are induced to die upon clonotypic engagement of TCR by self antigens. CD3 engagement by antibody of the surface TCR-CD3 complex is known to induce apoptosis of CD4⁺CD8⁺ thymocytes, a process that is generally thought to represent antigen-induced negative selection in the thymus. The present study shows that the CD3-induced apoptosis of CD4⁺CD8⁺ thymocytes can occur even in TCRα^? mutant mice which do not express the TCRαβ/CD3 antigen receptor. Anti-CD3 antibody induces death of CD4⁺CD8⁺ thymocytes in TCRα^? mice either in cell cultures or upon administration in vivo. Interestingly, most surface CD3 chains expressed on CD4⁺CD8⁺ thymocytes from TCRα^? mice are not associated with clonotypic TCR chains, including TCRβ. Thus, apoptosis of CD4⁺CD8⁺ thymocytes appear to be induced through the CD3 complex even in the absence of clonotypic antigen receptor chains. These results shed light on previously unknown functions of the clonotype-independent CD3 complex expressed on CD4⁺CD8⁺ thymocytes, and suggest its function as an apoptotic receptor inducing elimination of developing thymocytes.     

浆细胞性乳腺炎患者外周血CD4+CD25+CD127-调节性T细胞变化

目的:观察浆细胞性乳腺炎(Plasma cell mastitis,PCM)患者外周血CD4+ CD25+ CD127-调节性T细胞(CD4+CD25+ CD127-Treg)数量和功能变化,以探讨PCM免疫病理机制.方法:将58例浆细胞乳腺炎患者分成三组:其中急性组13例(22％)、亚急性组25例(43％)和慢性组20例(34％).并设正常对照组20例及乳腺癌对照组16例.以流式细胞术检测各型PCM患者外周血中CD4 +CD25+ CD127 Treg细胞百分率;实时荧光定量RT-PCR检测转录因子Foxp3表达及ELISA检测TGF-β水平.结果:三组PCM组与正常组相比,外周血CD4+ CD25+ CD127 Treg数量,外周血PBMC中Foxp3表达及血浆TGF-β水平均下降(P＜0.05),其中急性PCM组下降最为明显(P＜0.01),乳腺癌组三项指标均升高(P＜0.05).结论:浆细胞性乳腺炎患者的CD4+ CD25+ CD127-Treg数量及功能有所下降.     

小细胞和非小细胞肺癌晚期患者CD3~+ CD4~+及CD3~+ CD8~+T淋巴细胞亚群的差异

目的:探索小细胞和非小细胞肺癌晚期患者CD3+CD4+及CD3+CD8+T淋巴细胞亚群是否存在差异,并为治疗提供参考。方法:选取肺癌晚期患者共65例,其中包括小细胞肺癌14例,非小细胞肺癌51例以及20例健康对照。用流式细胞仪检测研究对象外周血淋巴细胞表面CD3+CD4+及CD3+CD8+的表达情况。结果:CD3+CD4+T细胞所占比例无论是小细胞还是非小细胞肺癌晚期的患者都较健康对照显著降低;CD3+CD8+T细胞所占比例在肺癌晚期的患者较健康对照并无显著变化;CD4+/CD8+比值在小细胞肺癌晚期患者较健康对照显著下降。结论:无论是小细胞还是非小细胞肺癌晚期的患者CD3+CD4+T细胞的水平较健康人都显著降低,说明肺癌晚期患者细胞免疫功能严重受损。     

铜绿假单胞菌群体感应系统对CD4~+CD25~+Treg细胞的影响

目的 探讨铜绿假单胞菌(Pseudomonas aeruginosa,PA)群体感应系统(quorum sensing system,QS)对CD4+CD25+Treg细胞的影响及作用机制.方法 60只雄性SD大鼠,随机分为铜绿假单胞菌野生菌株PAO1组,变异菌株PAO-JP2组(lasⅠ、rhlⅠ基因双变异)和空白对照组.将PA包被的硅胶管置入大鼠一侧主支气管建立慢性肺部感染模型,对照组置入无菌硅胶管.28 d后,FACs测外周血CD4+CD25+Treg细胞数量,ELISA测血清IL-10、TGF-β,RT-PCR测脾Foxp3mRNA表达水平,肺组织行HE染色.结果 CD4+CD25+Treg/CD4+T淋巴细胞的百分比:PAO1组(19.79±6.45)%,PAO-JP2组(11.03 ±3.92)%,对照组(5.15±0.47)%,PAO1组的百分比明显高于PAO-JP2组和对照组(P<0.05).IL-10:PAO1组(231.52±54.48)pg/mL,PAO-JP2组(60.10±29.64)ps/mL,对照组(35.43±23.56)PS/mL,PAO1组表达水平高于JP2、对照组(P<0.05).TGF-β:PAO1组、JP2组、对照组水平分别为(121.05±7.98)PS/mL、(63.11±5.73)ps/mL、(36.02±8.94)Pg/mL,PAO1组与PAO-JP2、对照组比较均有统计学意义.Foxp3mRNA相对含量:PAO1组(0.80±0.044),PAO-JP2组(0.41±0.044),对照组(0.25±0.054),PAO1组较其他两组含量显著升高(P<0.05).HE染色可见,PAO1组肺组织大量淋巴细胞聚集、纤维增生明显,脓肿形成;PAO-JP2组炎症细胞浸润叫PAO1组明显减轻,对照组未见明显异常.结论 PA群体感应系统通过提高IL-10、TGF-β和Foxp3mRNA的表达水平,上调CD4+CD25+Treg细胞的数量及功能,在慢性肺部感染中发挥重要作用.     

CD4+ CD25+ Treg regulate the contribution of CD8+ T-cell subsets in repopulation of the lymphopenic environment

Peripheral T‐cell expansion is of major relevance for immune function after lymphopenia. In order to promote regeneration, the process should result in a peripheral T‐cell pool with a similar subpopulation structure as before lymphopenia. We investigated the repopulation of the CD8⁺ central‐memory T cells (T_CM) and effector‐memory T cells (T_EM) pools after adoptive transfer of sorted CD8⁺ T cells from naïve, T_CM and T_EM subsets into T‐cell‐deficient hosts. We show that the initial kinetics of expansion are distinct for each subset and that the contribution to the repopulation of the CD8⁺ T‐cell pool by the progeny of each subset is not a mere function of its initial expansion. We demonstrate that CD4⁺CD25⁺ Treg play a major role in the repopulation of the CD8⁺ T‐cell pool and that CD8⁺ T‐cell subsets impact on each other. In the absence of CD4⁺CD25⁺ Treg, a small fraction of naïve CD8⁺ T cells strongly proliferates, correlating with further expansion and differentiation of co‐expanding CD8⁺ T cells. CD4⁺CD25⁺ Treg suppress these responses and lead to controlled repopulation, contributing decisively to the maintenance of recovered T_CM and T_EM fractions, and leading to repopulation of each pool with progeny of its own kind.     

Deficiencies in CD4+ and CD8+ T cell subsets in ataxia telangiectasia

Chronic sinopulmonary infections that are associated with immunodeficiency are one of the leading causes of death in the multi-systemic disease ataxia telangiectasia (AT). Immunological investigations of AT patients revealed a broad spectrum of defects in the humoral and the cellular immune system. Based on their important role in host defence the aim of our study was an extensive analysis of cell distribution and function of CD4+ and CD8+ T lymphocytes and NK cells. We found that naive (CD45RA+) CD4+ lymphocytes, as well as CD8+/CD45RA+ lymphocytes, are decreased, whereas NK cells (CD3-/CD16+CD56+) are significantly elevated in AT patients. In our culture system proliferation and cytokine production was normal in purified memory (CD45RO+) lymphocytes after stimulation with phorbol-12,13-dibutyrate (PBu2) and after PHA activation, indicating that differences in proliferation and cytokine production are due solely to reduced numbers of CD45RA+ lymphocytes. However, activation, and especially intracellular interferon production of AT lymphocytes, seem to follow different kinetics compared to controls. In contrast to polyclonal activation, stimulation via the T cell receptor results consistently in a reduced immune response. Taken together, our results suggest that deficiency of immunocompetent cells and an intrinsic immune activation defect are responsible for the immunodeficiency in AT.     

CD86对CD8+T细胞分化的影响

目的：探讨CD86(B7-2)对CD8^ T细胞分化的影响。方法：用限制性内切酶Xho Ⅰ酶切质粒pCDM8得到CD86基因，并将其插入pCDNA3，用BamH Ⅰ酶切鉴定。用脂质体法介导pCDNA3-CD86真核表达载体转染人肝癌细胞株HMCT／21，600μg/ml G418筛选，稳定且高表达CD86的抗性克隆用流式细胞仪进行鉴定。从健康志愿者血中分离外周血单个核细胞(PB-MC)，使PBMC与靶细胞之比为20：1，共同培养48h后，用流式细胞仪检测CD3^ T细胞内IL-4和IFN-γ的表达率。结果：成功构建pCDNA3-CD86真核表达载体；CD86在HMC7721-CD86细胞中的表达率为30．8％，而在HMC7721细胞中的表达率为0．98％；健康志愿者CD3^ T细胞内IL-4和IFN-γ的表达率分别为1．92％和24．4％；PBMC与靶细胞共同培养48h后，无论是否用IFN-α刺激，IL-4，IFN-γ的阳性比值在HMC7721-CD86转染组均大于1，而在HMC7721未转染组均小于1。结论：在细胞培养中，CD86可诱导CD8^ T细胞活化，并向Tc2表型转化。