连翘提取物对小鼠T淋巴细胞体外活化与增殖的影响

目的:分析连翘(FS)提取物对小鼠淋巴结T细胞的体外活化与增殖的影响,初步探讨其免疫抑制作用机制.方法:无菌分离小鼠淋巴结细胞,加入多克隆刺激剂刀豆蛋白A(ConA)进行刺激,利用荧光标记的单克隆抗体(mAb)染色结合流式细胞术(FCM),检测小鼠T淋巴细胞的表达的活化抗原CD69、CD25、CD71的表达情况;以羧基荧光素乙酰乙酸琥珀酰亚胺酯(CFDA-SE)染色,以FCM分析FS对淋巴细胞体外增殖的影响.结果:终浓度为40、80、160 mg/L的FS均对ConA刺激诱导的T细胞CD69、CD25和CD71的表达有降低作用(P＜0.05).CFDA-SE染色分析显示,上述浓度的FS对ConA诱导的小鼠T淋巴细胞增殖具有抑制作用(P＜0.05).结论:FS对ConA诱导的T细胞早、中、后期活化和体外增殖有抑制作用.     

可溶性Jagged 1/Fc嵌合蛋白对小鼠淋巴细胞活化、增殖和周期的影响

目的:研究可溶性Jagged 1/Fc嵌合蛋白在小鼠淋巴细胞活化、增殖和周期中的作用.方法:选择有效剂量为500 μg/L Jagged 1/Fc嵌合蛋白(Jagged 1/Fc),以活体染料/羧基荧光素乙酰乙酸琥珀酰亚胺酯染色,建立在多克隆刺激剂刀豆蛋白A(ConA)或佛波醇酯(PDB)加离子霉素(Ion)刺激下评价淋巴细胞增殖的模型,通过流式细胞术分析Jagged 1/Fc对淋巴细胞增殖的作用;采用碘化丙锭染色检测Jagged 1/Fc对PDB加Ion刺激的淋巴细胞周期变化的影响;利用荧光标记的mAb双染技术观察Jagged 1/Fc对T细胞早期和中期活化标志CD69和CD25表达的影响.结果:Jagged 1/Fc对ConA刺激或非刺激的CD3 细胞CD69和CD25的表达无明显影响,对ConA或PDB加Ion刺激或非刺激的淋巴细胞的增殖指数也无明显影响,导致非刺激的淋巴细胞sub-G0期细胞百分比增高,S期细胞百分比降低,但并不影响PDB加Ion诱导的淋巴细胞各期的变化.结论:这些结果提示500 μg/L Jagged 1/Fc对小鼠淋巴细胞活化和增殖无明显作用,对PDB加Ion刺激的淋巴细胞周期也无明显影响,但能促进未受刺激的淋巴细胞凋亡,使细胞停滞于GO/G1期,阻止其进入S期.     

紫杉醇对小鼠T细胞的影响

为研究抗癌药紫杉醇(PTX)对T细胞行为的影响及其分子机制,利用流式细胞术分析多克隆刺激剂ConA刺激下T细胞行为:羧基荧光素乙酰乙酸琥珀酰亚胺酯(CFSE)标记技术分析T细胞增殖相关指数;碘化丙锭染色分析细胞周期分布;AnnexinV-PI染色检测T细胞凋亡;荧光标记的单克隆抗体染色检测T细胞活化表达CD25的百分率。结果显示.PTX对ConA刺激下小鼠T细胞增殖具有明显的抑制作用,且呈剂量依赖性。该浓度范围PTX阻滞T细胞于G2/M期,诱导凋亡及抑制CD25表达。25nmol/L的PTX与10nmol/L的环孢素A(CsA)具有明显的协同抑制效应。以上结果表明PTX可明显抑制多克隆刺激剂ConA诱导的T细胞体外增殖,是G2/M期阻滞、凋亡诱导和CD25表达抑制等多种机制共同作用的结果。     

Forskolin对佛波醇酯类刺激的小鼠体外T淋巴细胞行为的影响

目的 分析Forskolin对佛波醇酯多克隆刺激剂(phorbol 12,13-dibutyrate,PDB)联合离子霉素(ionomycin,Ion)刺激的小鼠CD3+T淋巴细胞体外增殖和周期的影响,在此基础上进一步研究Forskolin对单纯PDB刺激的小鼠CD3+T淋巴细胞早期活化标志CD69分子和中期活化标志CD25分子的影响,从而阐明其作用机制.方法 无菌分离小鼠淋巴结并制备单个淋巴细胞悬液,与不同浓度的Forskolin孵育48h后,运用羧基荧光素已酰已酸(CFDA-SE)染色技术和碘化丙锭(PI)染色技术结合流式细胞术、CRLLQuest 和ModFitLT软件,分别榆测Fomkolin对PDB+Ion刺激下小鼠CD3+T淋巴细胞增殖和周期的影响;与不同浓度的Forskolin孵育2 h、10 h,运用流式细胞术结合双色荧光抗体染色技术检测Fomkolin对PDB诱导下的小鼠CD3+T淋巴细胞CD69分子和CD25分子表达的影响.结果 Forskolin(10-7、10-6、10-5 mol·L-1)均能明显抑制PDB+Ion刺激的小鼠CD3+T淋巴细胞的增殖并将细胞阻滞在G0/G1期;同时也能明显抑制单纯PDB刺激下的CD3+T细胞早期和中期活化,且呈明显的量效关系.结论 提示Forskolin在CD3+T细胞活化过程中信号转导的某个环节上有抑制作用,从而通过抑制T淋巴细胞的活化,发挥免疫抑制作用,是一种潜在的免疫抑制剂.     

芹菜素对小鼠T淋巴细胞体外活化和增殖的抑制作用

研究芹菜素(apigenin,AP)对小鼠T细胞体外活化和增殖的影响,探讨其作用机制,以及将其开发为免疫抑制药物的可能。无菌分离小鼠淋巴结细胞,加入不同浓度(25μmol/L、50μmol/L、100μmol/L、150μmol/L和200μmol/L)的芹菜素预孵育4 h,用多克隆刺激剂刀豆蛋白A(concanavalin A,ConA)诱导T细胞活化和增殖,并用MTT法检测该药物浓度对T细胞的毒性作用。荧光标记抗体双染色结合流式细胞术,检测各浓度AP对ConA诱导的小鼠T细胞表达早期、中期和晚期活化抗原CD69、CD25和CD71的影响;以二乙酰羧基荧光素-琥珀酰亚胺酯(carboxyfluoresceindiacetate-succinim-idyl ester,CFDA-SE)染色结合流式细胞术,检测各浓度AP对ConA诱导的小鼠T细胞增殖的影响,并应用ModFit软件分析其增殖指数(proliferation index,PI)。结果显示,25~200μmol/L AP对ConA诱导的T细胞CD69、CD25的表达有显著抑制作用(P<0.01),且呈剂量依赖关系;25μmol/L和50μmol/L的AP抑制CD71的表达,但高浓度(大于100μmol/L)才有显著抑制作用(P<0.01)。各浓度AP对ConA诱导的T细胞增殖均有显著抑制作用(P<0.01),且呈剂量依赖关系。表明在一定浓度范围内,AP可显著抑制ConA诱导的小鼠T细胞体外活化及增殖,有望通过进一步研究将其开发成免疫抑制药物。     

双氢青蒿素对小鼠T细胞的免疫抑制作用

目的:研究双氢青蒿素(DHA)在体外对ConA诱导的小鼠T细胞增殖的影响,探讨其可能的免疫作用机制。方法:加入不同浓度DHA,以多克隆刺激剂刀豆蛋白A(ConA)诱导T细胞活化增殖,用羧基荧光素双醋酸盐琥珀酰亚胺酯(CFDA-SE)染色法分析T细胞增殖情况;利用流式细胞术(FCM)结合双色免疫荧光染色技术检测CD3+T细胞早、中、晚期活化标志CD69、CD25、CD71表达情况;用Fluo-4/AM荧光钙离子探针技术检测细胞内钙离子([Ca2+]i)浓度的变化;以碘化丙锭(PI)染色分析细胞周期分布;运用流式细胞术(FCM)结合三色荧光染色技术检测CD4+CD25highTreg早期活化抗原CD69表达情况。结果:CFDA-SE染色结果显示,DHA能有效抑制ConA诱导的T细胞增殖,并呈时间-剂量依赖性;DHA对ConA刺激的CD3+T细胞CD69、CD25的表达有促进作用,而对CD71的表达有抑制作用,均呈剂量依赖性;DHA单独作用不能引起T细胞[Ca2+]i的升高,在ConA的刺激下能引起[Ca2+]i浓度升高;PI染色流式分析结果显示,DHA阻滞细胞于G0/G1期,阻止细胞进入S期和G2/M期;DHA能够下调CD4+CD25highTreg细胞CD69的表达。结论:DHA对小鼠淋巴细胞的增殖有明显的抑制作用,是一种潜在的免疫抑制剂。     

槲皮素对小鼠T细胞体外活化的抑制作用

目的:通过分析槲皮素对淋巴细胞早期活化标记物CD69表达的影响,探讨其对T淋巴细胞体外活化抑制作用的机制。方法:分离小鼠淋巴结细胞,加入多克隆刺激剂及槲皮素共同培养,分别于2、6、24h收获细胞,进行双色免疫荧光标记,以流式细胞仪对T细胞的CD69分子表达情况进行分析并计算抑制率。结果:槲皮素(终浓度10μmol/L)对未受刺激的T细胞CD69表达百分率无明显影响,而经佛波醇酯(PDB)及刀豆蛋白A(ConA)活化同时加入槲皮素的T细胞CD69表达百分率在2h、6h及24h均显著下降(P＜0.01)。槲皮素对PDB的抑制率随作用时间延长而明显下降,对ConA的抑制率平缓而持久。结论:槲皮素对PDB、ConA活化的T淋巴细胞均显示明显的抑制效应,表明该药可能作用于T细胞活化信号传递通路蛋白激酶Cθ或其下游部位,并且,这种抑制效应表现出一定的可逆性。     

双黄连粉针剂对小鼠T淋巴细胞体外活化与增殖的影响

目的:探讨双黄连粉针剂(以下简称SHL)对小鼠T淋巴细胞的体外活化和增殖的影响.方法:MTT法检测SHL对小鼠淋巴细胞的毒副作用;双色荧光抗体染色技术结合流式细胞术分析SHL对小鼠T淋巴细胞在多克隆刺激剂(ConA)刺激下体外活化抗原CD69表达的影响;MTT法以及羧基荧光素乙酰乙酸(CFDA-SE)标记技术结合流式细胞术分析SHL对小鼠T淋巴细胞在ConA诱导下体外增殖的影响.结果:SHL对小鼠淋巴结来源的淋巴细胞毒副作用非常小;终质量浓度为60、 80、 100、 120 mg/L的SHL对ConA刺激下的T淋巴细胞体外活化抗原CD69表达具有抑制作用(P<0.01);MTT法和CFDA-SE染色法都显示, 终质量浓度为60、 80、 100、 120 mg/L的SHL对ConA诱导的T淋巴细胞增殖作用具有明显的抑制作用(P<0.01).结论:SHL对小鼠T淋巴细胞的体外活化和增殖具有明显的抑制作用.     

红车轴草提取物对小鼠T淋巴细胞体外活化的抑制作用

探讨红车轴草提取物(Trifolium pratense Leguminosae extract,TLE)对小鼠T淋巴细胞的体外活化的影响。无菌条件下制备小鼠淋巴细胞悬液;双色荧光抗体染色结合流式细胞术分别分析TLE对小鼠T淋巴细胞在刀豆蛋白A(ConA)或佛波醇酯(PDB)刺激下的体外分化抗原CD69、CD25、CD71表达的影响。终质量浓度为20、30、40 mg/L的TLE对小鼠T淋巴细胞在ConA或PDB刺激下的体外分化抗原CD69、CD25、CD71表达具有明显的抑制作用(P<0.01)。TLE对ConA或PDB刺激的不同时期的小鼠T淋巴细胞的体外活化具有明显的抑制作用。     

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。     

Microgravity Inhibits Resting T Cell Immunity in an Exposure Time-Dependent Manner

Background: Decline immune function is well documented after spaceflights. Microgravity is one of the key factors directly suppressing the function of immune system. Though T cell immune response was inhibited by microgravity, it is not clearly whether activation would be inhibited after a pre-exposure of microgravity on T lymphocytes at the resting state. Methods: We herein investigated the response ability of resting CD4⁺ and CD8⁺ T cells experiencing pre-exposure of modeled microgravity (MMg) for 0, 8, 16 and 24 hrs to concanavalin A (ConA) stimulation. The phenotypes and subsets of immune cells were determined by flow cytometry. Results: Both CD4⁺ and CD8⁺ T cells with an MMg pre-exposure exhibited decreased expressions of activation-markers including CD25, CD69 and CD71, inflammatory cytokine secretion and cell proliferation in response to ConA compared with T cells with 1g controls in an MMg exposure time- dependent manner. Moreover, short term MMg treatment caused more severe decreased proliferation in CD4⁺ T cells than in CD8⁺ T cells. Conclusions: MMg can directly impact on resting T cell subsets. CD4⁺ T cells were more sensitive to the microgravity inhibition than CD8⁺ T cells in respect of cell proliferation. These results offered new insights for the MMg-caused T cell functional defects.     

Positive regulation of human T cell activation by Gi2 proteins and interleukin-8

We investigated whether pertussis toxin (PT)-sensitive heterotrimeric Gi proteins (Gi1, Gi2, Gi3) are involved in the regulation of TCR-induced activation of human T cells. First, Gi proteins were inactivated by PT: pretreatment with PT of purified blood T lymphocytes before CD3 cross-linking inhibited cell proliferation (-71.1 +/- 22.0%, P < 0.001), production of interleukin-2 (IL-2; -47.3 +/- 12.6%, P = 0.008), and expression of CD25 (-24.6 +/- 11.7%, P < 0.001) and CD69 (-25.7 +/- 9.0%, P < 0.001). Then, to identify which of the three Gi was involved, Gi1, Gi2, and Gi3 proteins were specifically inactivated by stably transfecting dominant-negative mutated forms of their alpha subunit in Jurkat cells. After activation, IL-2 production and CD69 expression were inhibited only in cells expressing inactive Gi2. We then studied the effects of interleukin-8 (IL-8), a CXC-chemokine with receptors coupled to Gi2 and produced in an autocrine fashion by activated T cells. Although its effects varied among donors, exogenous IL-8 stimulated proliferation and CD25 expression (up to, respectively, 200 and 77%) of PB T lymphocytes in response to CD3 activation, in a PT-sensitive manner. IL-8 also stimulated IL-2 production (by up to 42%) and CD69 expression, although weakly (+27%). Anti-human IL-8 antibody inhibited proliferation (-43%) and CD25 up-regulation (-45%) of activated T lymphocytes. In summary, several major responses of human T lymphocytes to TCR-mediated activation are regulated by Gi2 proteins, which for this function can be activated by IL-8 in an autocrine manner.     

通痹灵总碱对活化的小鼠T淋巴细胞CD69表达的影响

目的：研究通痹灵（TBL）总碱对活化的小鼠T淋巴细胞表达CD69的影响及其可能的免疫调控机制。方法：培养小鼠淋巴细胞，加入不同浓度的TBL总碱预孵1h后，再加佛波醇酯（PDB）或刀豆蛋白（ConA).24h后，用流式细胞术检测T淋巴细胞CD69的表达率。结果；不同质量浓度的TBL总碱对PDB或ConA激活的T淋巴细胞表达CD69，均有明显的下调作用（对ConA激活的T淋巴细胞表达CD69。均有明显的下调作用（对ConA激活的T淋巴细胞的作用要强于PDB激活的T淋巴细胞）。呈明显的量效关系。结论：TBL总碱可明显抑制活化的小鼠T淋巴细胞CD69的表达，为其用于类风湿性关节炎的治疗提供了实验依据。     

Inhibitory effect of somatostatin on human T lymphocytes proliferation

Somatostatin (SOM) was originally described as a growth hormone release inhibiting factor, but SOM and its specific receptors (SOM-r) have been shown to be expressed on both normal and activated T and B lymphocytes and other immunocompetent cells. In the present study we have demonstrated that SOM strongly inhibits the proliferation of human T lymphocytes when stimulated by PHA, Con A or alloantigens. However, SOM was most effective when the T cells were stimulated by an alloantigen rather than a polyclonal activator such as PHA and ConA. Moreover, SOM strongly inhibited the expression of activation markers such as CD69 and CD25 that are expressed on T lymphocytes during alloantigen stimulation. SOM also inhibited both CD28 and CD2 mediated T cell proliferation. Whereas proliferation of T cells induced by the engagement of CD3 antigen using specific mAbs was only marginally affected. Our results would support the concept that in humans SOM plays a key role in the modulation of T cell activation by interfering with the antigen-independent pathways CD2 and CD28.     

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。     

钛离子对T淋巴细胞体外增殖及活化的影响

BACKGROUND: Titanium ions have been proved to stimulate the secretion of bone remodeling-related factors from T lymphocytes; however, the effects of titanium ions on the early activation, intermediate activation, and cell cycle of T lymphocytes remain unclear. OBJECTIVE: To investigate the effects of titanium ions on the proliferation and activation of T lymphocytes in vitro. METHODS: Cell proliferation and cycle test: Jurkat E6-1 T lymphocytes in logarithmic phase were collected and cultured in the medium containing 0 (control), 25 (low concentration), 50 (middle concentration), and 100 μmol/L (high concentration) titanium ions for 24 hours to detect the cell relative proliferation rate and cell cycle. Cell activation trial: Jurkat E6-1 T lymphocytes were divided into two groups that were subdivided into four groups containing 0, 25, 50, and 100 μmol/L titanium ions, respectively with or without phytohemagglutinin (PHA) pre-stimulation. The expressions of CD69 and CD25 were measured after cultured for 24 hours. RESULTS AND CONCLUSION: Titanium ions enhanced T lymphocytes proliferation in a concentration-dependent manner (P < 0.05). Compared with the control group, the percentages of G₀/G₁ phase decreased and the proportions of cells in S and G2/M phase increased significantly in the low, middle and high concentration groups (P < 0.05). The proportion of G₀/G₁-phase cells in the high concentration group was less and the proportion of G₂/M phase cells was higher than those in the middle and low concentration groups (P < 0.05). With PHA pre-stimulation, the expression of CD69 in the high concentration group was higher than that in the middle and low concentration groups (P < 0.05); whereas the difference of CD25 expression was not significant among four subgroups. Titanium ions promoted the expression of CD69 in a concentration-dependent manner (P < 0.05), but there was no CD25 expression in each subgroup without PHA pre-stimulation. To conclude, titanium ions can significantly promote T lymphocyte proliferation and early activation in vitro, and moreover, induce S and G₂/M phase arrest in T lymphocytes.