人胎盘源间充质干细胞对脐血CD8~+T细胞活化及周期和IL-17分泌的影响

目的:探讨人胎盘源间充质干细胞(hPMSCs)对脐血CD8+T细胞活化、周期及IL-17分泌的调节作用,为其在临床细胞治疗中的应用提供理论依据。方法:应用消化法分离、培养hPMSCs,体外扩增培养3代后用于实验;应用免疫磁珠法分选脐血CD8+T细胞;应用流式细胞术(FCM)分析hPMSCs对植物血凝素(PHA)刺激下脐血CD8+T细胞早期表型CD25、CD69表达和细胞周期的影响;佛波酯(PMA)刺激下脐血CD8+T细胞对IL-17分泌的影响。结果:hPMSCs体外可使脐血CD8+T细胞滞留于细胞周期的G0/G1期,下调活化脐血CD8+T细胞早期表型CD25、CD69的表达,上调其IL-17的分泌。结论:hPMSCs体外可通过对脐血CD8+T细胞周期的影响抑制其活化,并且上调脐血CD8+T细胞IL-17的分泌。     

黄连素对T淋巴细胞活化和增殖的抑制作用

目的:研究黄连素(Ber)对T细胞体外活化和增殖的影响及作用机制。方法:正常人外周血全血培养,以植物血凝素(PHA)或佛波醇酯(PDB)加离子霉素(Ion)刺激活化淋巴细胞,双荧光染色及溶血获取有核细胞后,以流式细胞仪分析T细胞表达活化抗原CD69和CD25的水平,并以碘化丙锭染色分析细胞周期分布,7-AAD活染分析细胞死亡率。结果:浓度为100μmol/L和50μmol/L的Ber对PDB+Ion或PHA激活T细胞表达CD69有明显抑制,而25μmol/L的Ber抑制效应无显著性;随时间延长,对CD69表达的抑制程度下降;对于CD25表达,上述3个浓度的Ber抑制作用均有显著性,且呈剂量依赖性。同时,这3个浓度的Ber均能明显阻止淋巴细胞进入S期和G₂/M,对细胞周期的抑制作用没有时相特异性。活染分析显示Ber对淋巴细胞无明显细胞毒性。结论:Ber通过干扰早期活化信号转导通路而抑制T细胞活化和增殖,发挥其免疫抑制作用。     

PD-L1信号对T细胞体外激发的调节作用

目的　探讨PD L1信号在PHA体外激发体系中对人外周血T细胞的协同调节作用。方法　采用 10 μg/mlPHA刺激人外周血T细胞体外培养体系 ,加入转基因细胞PD L1/L92 9混合培养 ;免疫荧光标记和流式细胞仪分析T细胞表型及细胞周期 ;3 H TdR掺入法观察T细胞的增殖 ;ELISA法检测T细胞对IL 2和IFN γ的产生。结果　PD L1转基因细胞在PHA激发T细胞增殖的培养体系中 ,具有显著下调T细胞活化表型 ,抑制T细胞对PHA促增殖的反应性 ,这种抑制效应与其阻断T细胞于G0 /G1细胞周期及使活化T细胞分泌IL 2和IFN γ的水平下降有关。同时还发现PD L1信号能抑制PHA介导的T细胞活化诱导凋亡。结论　PD L1信号在体外PHA激发T细胞培养体系中 ,具有显著的负性调节其活化增殖和相应功能的作用     

棉酚对多克隆激活剂活化人T淋巴细胞的抑制作用

目的:以体外培养的人外周血单个核细胞为材料,研究多酚类抗生育药物棉酚对正常人外周血T淋巴细胞体外活化作用的影响。方法:利用双荧光染色流式细胞术分析棉酚对人T淋巴细胞在丝裂原或佛波醇酯刺激下早期活化抗原CD69表达的影响。结果:100μmol/L的棉酚预先与T细胞温育,能完全抑制10mg/L植物血凝素(PHA)刺激的CD3^＋T细胞活化抗原CD69的表达,又可阻断10^－7mol/L佛波醇酯(PDB)对T细胞的活化作用。这种抑制作用呈剂量依赖性,棉酚对PDB及PHA抑制作用的IC₅₀分别为(35.7±2.9)μmol/L和(32.8±1.5)μmol/L。此外,棉酚对CD3^－的淋巴细胞CD69表达也有类似的抑制作用。然而,它对多克隆激活剂引起的T细胞表面分子CD3的下调无明显影响。结论:在体外活化模型中,棉酚能够同时抑制多克隆激活剂PHA和PDB对T细胞的活化作用,提示其作用部位可能位于PKC或下游,并提示棉酚具有潜在的免疫调节作用。     

B7-H3在人肝癌细胞株HepG2对外周血CD8+T细胞活化、周期及分泌IL-17调节中的作用

目的 研究B7-H3在人肝癌细胞株HepG2对人外周血CD8+T细胞活化、周期及IL-17分泌等调节中的作用.方法 RT-PCR及FCM检测B7-H3在HepG2细胞上的表达;应用脂质体法将PGPU6/GFP/neo-B7-H3shRNA质粒转入肝癌细胞株HepG2,阻断B7-H3的表达;免疫磁珠分选健康人外周血CD8+T细胞;FCM分析B7-H3分子在HepG2细胞对PHA刺激下CD8+T细胞活化、周期及PMA刺激下CD8+T细胞分泌IL-17调节中的作用.结果 肝癌细胞株HepG2高表达B7-H3分子,PGPU6/GFP/neo-B7-H3 shRNA质粒能有效阻断B7-H3在HepG2细胞上的表达;FCM分析结果显示,肝癌细胞株HepG2对CD8+T细胞活化及周期均有抑制作用;阻断B7-H3的表达后,明显减弱HepG2细胞对CD8+T细胞早期活化表型CD69表达的抑制作用,且能够通过下调CD8+T细胞Go/G1期细胞数量,上调S期细胞数量逆转HepG2细胞对CD8+T细胞周期的阻滞作用;在HepG2存在条件下,CD8+T细胞对IL-17的分泌明显增加,阻断B7-H3的表达后,IL-17的分泌被进一步上调.结论 HepG2细胞高表达B7-H3分子;B7-H3能够协同HepG2细胞对CD8+T细胞活化表型CD69的表达及细胞周期的抑制作用;HepG2细胞上调CD8+T细胞对IL-17的分泌作用,但B7-H3可抑制该上调作用.     

环孢素A治疗再障和骨髓增生异常综合征T淋巴细胞异常激活的变化

研究再生障碍性贫血(AA)用环孢素A(CsA)治疗前后和骨髓增生异常综合征(MDS)患者外周血CD4+、CD8+T淋巴细胞培养前后早期激活标志CD69的表达及其意义。将外周血在PHA20μg/ml条件下进行全血细胞培养,于0h和4h分别用双色免疫荧光标记流式细胞仪对CD4+、CD8+T淋巴细胞CD69的表达进行分析。发现PHA刺激前初治SAA和MDS-RA+MDS-RAS患者CD4+、CD8+细胞CD69的表达率增高,CAA与RAEB+RAEB-T患者CD8+细胞CD69的表达率增高;PHA刺激后AA与MDS患者CD4+、CD8+细胞表达CD69明显增强,AA患者CD4+细胞CD69的表达率高于CD8+细胞。CsA治疗后SAA患者PHA刺激前CD4+、CD8+细胞CD69的表达率较治疗前明显减低,CAA患者CD8+细胞CD69的表达率较治疗前明显减低。治疗后AA患者PHA刺激后CD4+、CD8+细胞CD69的表达率较治疗前明显减低。CsA治疗有效的AA患者治疗前PHA刺激前后CD4+、CD8+细胞CD69的表达率明显增高,治疗后明显减低。初治AA患者PHA刺激前后CD4+细胞CD69的表达率均明显高于MDS患者。说明T细胞早期活化及其活化潜能增强,以及产生针对自身造血干/祖细胞的细胞毒效应在AA和MDS发病中起重要作用,CsA能抑制AA患者T细胞的早期激活。     

对早期凋亡细胞的吞噬抑制T淋巴细胞活化的实验研究

目的:研究早期凋亡细胞及吞噬早期凋亡细胞的巨噬细胞对T淋巴细胞活化的影响。方法:体外以紫外线照射,诱导出早期凋亡的Jurkat细胞;建立早期凋亡细胞的吞噬模型;ELISA法分析早期凋亡细胞对LPS刺激下巨噬细胞分泌细胞因子的影响及在早期凋亡细胞和吞噬了早期凋亡细胞的巨噬细胞干预下,ConA刺激T淋巴细胞活化后CD69、CD25、CD71表达的变化。结果:巨噬细胞吞噬了早期凋亡细胞后,抑制性细胞因子(TGF_β1)的分泌明显上调,并且在一定程度上抑制了ConA刺激下的T淋巴细胞活化;具体表现为CD69、CD25、CD71等T淋巴细胞活化标志的表达受到明显抑制。当加入TGF_β1中和抗体后,这种抑制作用消失。结论:巨噬细胞吞噬了早期凋亡细胞后抑制ConA刺激下的T淋巴细胞CD69、CD25、CD71的表达,这种抑制作用依赖于的TGF_β1分泌增强。     

间充质干细胞对混合淋巴细胞反应体系中T淋巴细胞的免疫调节作用

目的:探讨间充质干细胞(MSC)在体外对T淋巴细胞免疫调节作用的特点。方法:通过Ficoll梯度密度离心法分离出正常人骨髓单个核细胞,体外培养扩增MSC,获取第3代细胞。将其按照不同的比例加入双向混合淋巴细胞培养(MLC)体系中,在第3、5天,采用MTT比色法检测各组MLC中的T淋巴细胞的增殖情况,再用流式细胞术分析其与MSC共孵育前后细胞表面标记的变化情况。结果:加入了MSC的MLC体系中,MSC对T淋巴细胞的增殖抑制具有剂量依赖性,且随着时间延长,抑制程度增强;其中,CD4 T细胞亚群受抑不如CD8 T细胞亚群显著;另外,T淋巴细胞表面CD25的表达虽然较对照组有所下降,但是CD4、CD25共表达的细胞却较对照组有明显的上升趋势。T淋巴细胞表面活化抗原HLA-DR的表达较对照组有轻度减低。结论:MSC在体外能够明显抑制T淋巴细胞的增殖,其主要是针对CD8 T细胞(CTL)。另外,它还能下调活化T淋巴细胞上一些较特异的表面标记CD25和HLA-DR的表达。     

PD-L1在人胎盘源间充质干细胞对脐血CD8~+T细胞免疫调节中的作用

目的:研究PD-L1在人胎盘源间充质干细胞(Human placenta mesenchymal stem cell,hPMSCs)介导的对脐血CD8+T细胞活化、周期及对IL-17分泌免疫调节中的作用。方法:RT-PCR及FCM检测hPMSCs对PD-L1的表达;应用化学合成的PD-L1 siRNA阻断PD-L1在hPMSCs上的表达;免疫磁珠分选脐血CD8+T细胞;FCM分析阻断PD-L1后,hPMSCs对PHA刺激下CD8+T细胞活化、周期及PMA活化下CD8+T细胞分泌IL-17的影响。结果:hPMSCs高表达PD-L1分子,PD-L1 siRNA能有效阻断hPMSCs对PD-L1的表达;FCM分析结果显示,hPMSCs能够抑制CD8+T细胞对CD69的表达,但阻断PD-L1后,CD69的表达与未阻断组相比无明显变化;与未阻断组相比,处于G0/G1期的CD8+T细胞数量明显减少,处于S期的细胞数量明显增加;在hPMSCs存在条件下,脐血CD8+T细胞对IL-17的分泌明显增加,阻断PD-L1的表达后,IL-17的分泌被进一步上调。结论:PD-L1在hPMSCs上表达能够协同hPMSCs对脐血CD8+T细胞周期的抑制,并且能够抑制hPMSCs上调CD8+T细胞对IL-17的分泌。     

染料木黄酮对小鼠T细胞体外活化及增殖的影响

目的:研究染料木黄酮(Gen)对T细胞体外活化及增殖的影响,并探讨其机制。方法:利用荧光标记的单克隆抗体染色结合流式细胞术,检测多克隆刺激剂佛波醇酯(PDB)或刀豆蛋白(ConA)刺激下小鼠T细胞表达活化抗原CD69、CD25的百分率;以羧基荧光素乙酰乙酸(CFSE)标记技术结合流式细胞术,分析PDB＋Ion(Ionomycin)或ConA刺激下T细胞增殖相关指数。结果:Gen对ConA刺激组T细胞CD69、CD25表达有明显抑制作用(P＜0.05),且呈剂量依赖关系,而对PDB刺激组T细胞CD69及CD25表达的抑制需要较高浓度(＞50μmol/L);Gen无论对ConA或PDB＋Ion刺激组T细胞增殖均有显著抑制作用(P＜0.01),且均呈剂量依赖关系。结论:Gen可明显抑制多克隆刺激剂诱导的T细胞体外活化及增殖,其作用机制可能是抑制早期活化相关蛋白酪氨酸激酶活性。     

Enhanced antigen-specific primary CD4+ and CD8+ responses by codelivery of ovalbumin and toll-like receptor ligand monophosphoryl lipid A in poly(D,L-lactic-co-glycolic acid) nanoparticles

The purpose of this research was to investigate the use of biodegradable poly(D,L-lactic-co-glycolic acid) nanoparticles (PLGA-NP) as a vaccine delivery system to codeliver antigen, ovalbumin (OVA) along with monophosphoryl lipid A (MPLA) as adjuvant for induction of potent CD4(+) and CD8(+) T cell responses. The primary CD4(+) T responses to OVA/MPLA NP were investigated using OVA-specific T cells from DO11.10 transgenic mice. Following adoptive transfer of these cells, mice were immunized s.c. by NP formulations. For assessing the CD8(+) responses, bone marrow derived dendritic cells (DCs) were pulsed with different OVA formulations, then, cocultured with CD8(+) T cells from OT-1 mice. T cell proliferation/activation and IFN-gamma secretion profile have been examined. Particulate delivery of OVA and MPLA to the DCs lead to markedly increase in in vitro CD8(+) T cell T cell proliferative responses (stimulation index >3000) and >13-folds increase in in vivo clonal expanded CD4(+) T cells. The expanded T cells were capable of cytokine secretion and expressed an activation and memory surface phenotype (CD62L(lo), CD11a(hi), and CD44(hi)). Codelivery of antigen and MPLA in PLGA-NP offers an effective method for induction of potent antigen specific CD4(+) and CD8(+) T cell responses.     

Differentiation of human mesenchymal stem cells into mesangial cells in post-glomerular injury murine model

AIMS: Adult human bone marrow contains a population of mesenchymal stem cells (MSC) that contributes to the regeneration of tissues such as bone, cartilage, muscle, tendon, and fat. In recent years, it has been shown that functional stem cells exist in the adult bone marrow, and they can contribute to renal remodelling or reconstitution of injured renal glomeruli, especially mesangial cells. The purpose of this study is to examine the ability of MSC isolated from human bone marrow to differentiate into mesangial cells in glomerular injured athymic mice. METHODS: MSC were isolated from human bone marrow mononuclear cells based on plastic adherent properties and expanded in vitro in the culture medium. Human mesenchymal stem cells (hMSC) were characterised using microscopy, immunophenotyping, and their ability to differentiate into adipocytes, chondrocytes, and osteocytes. hMSC were then injected into athymic mice, which had induced glomerulonephropathy (GN). RESULTS: Test mice (induced GN and infused hMSC) were shown to have anti-human CD105(+) cells present in the kidneys and were also positive to anti-human desmin, a marker for mesangial cells. Furthermore, immunofluorescence assays also demonstrated that anti-human desmin(+) cells in the glomeruli of these test mice were in the proliferation stage, being positive to anti-human Ki-67. CONCLUSIONS: These findings indicate that hMSC found in renal glomeruli differentiated into mesangial cells in vivo after glomerular injury occurred.     

Virus-induced non-specific signals cause cell cycle progression of primed CD8(+) T cells but do not induce cell differentiation.

In this report the significance of virus-induced non-specific T cell activation was re-evaluated using transgenic mice in which about half of the CD8(+) T cells expressed a TCR specific for amino acids 33-41 of lymphocytic choriomeningitis virus glycoprotein I. This allowed tracing of cells with known specificity and priming history in an environment also containing a normal heterogeneous CD8(+) population which served as an intrinsic control. Three parameters of T cell activation were analyzed: cell cycle progression, phenotypic conversion and cytolytic activity. Following injection of the IFN inducer poly(I:C), proliferation of memory (CD44(hi)) CD8(+) T cells but no phenotypic or functional activation was observed. Following injection of an unrelated virus [vesicular stomatitis virus (VSV)], naive TCR transgenic cells did not become significantly activated with respect to any of the parameters investigated. In contrast, memory TCR transgenic cells were found to proliferate extensively early after VSV infection (day 0-3), whereas limited proliferation was observed later (day 3-6) when proliferation of non-transgenic CD8(+) T cells is maximal. This aborted response did not result from anergy to TCR stimulation, as memory TCR transgenic cells proliferated vigorously upon stimulation with their nominal peptide. Despite the massive proliferation of memory cells observed early after VSV infection, no phenotypic or functional activation was observed. Together these findings indicate that both non-specific and antigen-specific signals contribute to the initial virus-induced proliferation of CD8(+) T cells, but for further proliferation and differentiation to take place, TCR-ligand interaction is required. The implications for maintenance of T cell memory is discussed.     

水仙环素抑制T细胞增殖的作用机制

目的探究水仙环素抑制T细胞增殖与功能的作用机制。方法密度梯度离心法及免疫磁珠法纯化人外周血T细胞,anti-CD3/anti-CD28抗体活化T细胞。使用流式细胞仪检测细胞增殖、CD25的表达、细胞毒性及细胞周期;酶联免疫吸附试验检测细胞因子IL-2、IL-6、IL^-17及IFN-γ的分泌水平。结果水仙环素抑制anti-CD3/anti-CD28抗体活化的T细胞增殖,IC₅₀为(0.011±0.001)μmol·L^-1,且浓度达0.24μmol·L^-1也不影响静息T细胞的存活。水仙环素抑制活化T细胞表达CD25和分泌IL-2,阻滞T细胞周期于G_0/G_1期。水仙环素对细胞因子IL-6、IL^-17及IFN-γ的抑制作用呈剂量依赖效应。结论水仙环素抑制T细胞增殖活化并显著抑制促炎细胞因子分泌,提示水仙环素有望成为先导化合物开发新型免疫抑制剂。     

Role of autologous CD4+ T cell clones in human B non-Hodgkin's lymphoma: aborted activation and G1 blockade induced by cell-cell contact.

This article describes the study of the functional relationship between auto-tumor-reactive CD4(+) T cell clones (TCC) and autologous malignant B cells. Four auto-tumor-reactive CD4(+) TCC were derived from tumor-infiltrating T lymphocytes (TIL-T) from a freshly isolated human follicular lymphoma by the following technique: total CD4(+) TIL-T were negatively purified by an immunomagnetic procedure, then CD4(+) TCC were obtained by limiting dilution in the presence of IL-2 and autologous non-irradiated follicular lymphoma cells as feeders. After expansion, these CD4(+) TCC were co-cultured with non-irradiated autologous malignant B cells. All four TCC were activated by B lymphoma cells and proliferated, as assessed by CD25 expression and cell cycle analysis. Activation and proliferation of B lymphoma cells were studied in response to activated CD4(+) T cells. Although all four TCC were able to induce B lymphoma cell activation (Ki-67 antigen induction and CD40 up-regulation), cells were subsequently blocked in G1 phase. Activation of B-NHL cells was mediated by TCR-HLA class II interaction, as shown by a blocking experiment using an anti-CD4 monoclonal antibody (mAb). Since anti-CD40 mAb with or without IL-4 did not induce proliferation of B lymphoma cells in contrast to normal B cells, we suggest that the blockade in G1 phase is due to the presence of abnormalities in B lymphoma cells. This is the first evidence that autologous reactive CD4(+) TCC can engage follicular lymphoma B cells to enter the cell cycle and induce an aborted activation stage.     

体外传代培养成体大鼠骨髓间充质干细胞生物学特性的观察

目的观察成体大鼠骨髓间充质干细胞（MSC）体外培养过程中生物学特性的改变,为骨髓间充质干细胞的应用研究提供实验依据。方法成体大鼠骨髓MSC的分离培养,流式细胞仪观察MSC免疫表型及细胞周期,检测细胞的诱导分化能力以及细胞的生长曲线,TRAP—ELISA方法检测其端粒酶活性。结果体外培养的成体大鼠MSC,随着传代次数的增加,长梭形细胞的体积逐渐增大。第4代时免疫表型阳性细胞率分别为CD29：（94．75±3．68）％,CD71：（95．43±2．23）％,CD90：（98．08±3．88）％;当传到第7代时,阳性细胞率仅为CD29：（50．00±3．35）％,CD71：（50．70±2．43）％,CD90：（48．60±2．83）％;第9代时MSC检测不到任何阳性免疫表型。前5代MSC增殖较快,第3代时处于S期和G2／M期的细胞比例为（38．36±2．01）％,处于G0／G1期细胞为（61．64±2．13）％;第7代以后细胞增殖能力明显降低,第12代时处于S期和G2／M期的细胞为（10．83±1．63）％,而G0／G1期的细胞为（89．17±1．96）％,此时MSC已经基本停止增长。当体外培养的MSC传到第9代以后,在成骨和成脂肪诱导体系作用下,细胞丧失了分化为Von Kossa法染色和油红O染色阳性细胞的能力;同时其端粒酶活性也随着传代次数的增多由最初的（52．7±0．78）％逐渐降低为阴性。结论体外培养的成体大鼠骨髓MSC随着传代次数的增加,其生物学特性发生明显改变。     

芍药苷对骨髓间充质干细胞增殖的影响

背景：研究显示芍药苷具有补血及治疗自身免疫性疾病的功效,骨髓间充质干细胞对机体的造血及免疫功能也起着重要的作用,但芍药苷对骨髓间充质干细胞的增殖及细胞因子的分泌和表达有何影响报道较少。 目的：探讨芍药苷对人骨髓间充质干细胞增殖及白细胞介素6表达的影响。 方法：采用密度梯度离心法和贴壁培养法体外分离培养人骨髓间充质干细胞,用流式细胞术和成脂及成骨诱导法鉴定人骨髓间充质干细胞生物学特性,MTT法检测不同浓度芍药苷对人骨髓间充质干细胞增殖的影响,ELISA 法测定芍药苷干预人骨髓间充质干细胞后培养上清液中白细胞介素6的分泌水平,RT-PCR 检测芍药苷干预后白细胞介素6 mRNA的表达情况。 结果与结论：成功分离出骨髓间充质干细胞,具有成骨、成脂分化潜能。与对照组相比,芍药苷浓度为2 μmol/L和10 μmol/L可明显促进骨髓间充质干细胞增殖。10 μmol/L芍药苷干预骨髓间充质干细胞后,G₀/G₁期细胞比例显著降低,S期细胞比例显著升高。10 μmol/L芍药苷干预组骨髓间充质干细胞白细胞介素6的分泌和mRNA表达均显著高于对照组(P < 0.01)。由此得出,一定浓度的芍药苷可促进骨髓间充质干细胞增殖,并提高骨髓间充质干细胞分泌白细胞介素6水平和基因表达。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：