雌激素与IL-6、IL-8在卵巢癌细胞中的调节作用

目的 探讨雌激素与IL-6、IL-8在卵巢癌细胞中的交互调节作用及作用机制.方法 选择兼有雌激素受体(estrogen receptor,ER)及IL-6、IL-8受体表达的卵巢癌细胞系CAOV-3和OVCAR-3作为研究模型,分别探讨17B-雌二醇(estradiol,E2)对IL-6、IL-8及其受体表达的作用以及IL-6、IL-8对EB表达及ER转录活性的作用.结果 一方面E2不仅可经NF-κB途径促进卵巢癌细胞IL-6、IL-8分泌,而且还对二者受体的表达具有一定的调节作用.E2诱导的促IL-6、IL-8分泌作用可被其受体阻断剂他莫昔芬(tamoxifen,Txf)完全阻断.另一方面在无雌激素的条件下,IL-6、IL-8能上调卵巢癌细胞Erα表达及下调ERB表达,且还能分别通过丝裂原活化蛋白激酶(MAPK)信号通路和Src活化增强卵巢癌细胞ER的转录活性,该作用可被Txf完全封闭.结论 雌激素与IL-6、IL-8两种细胞因子在卵巢癌细胞中交互调节,由此通过产生的放大信号通路促进卵巢癌的生长和发展.     

DHT、IL-6和IL-8对卵巢癌细胞体外增殖的作用

目的探讨雄激素与细胞因子在上皮性卵巢癌生长中可能存在的相互调节作用。方法应用免疫印迹（Western blot）和RT-PCR技术对5种常见的上皮性卵巢癌细胞系雄激素受体（AR）、ID6受体（IL-6Rα、gp130）及IL-8受体（IL-8RA、IL-8RB）的表达进行检测，选择兼有AB、IL-6R及IL-8R的卵巢癌细胞系作为研究模型，应用MTT法观察5α-二氢睾酮（5α-dihydrotestosterone，DHT）及IL-6、ID-8两种细胞因子对卵巢癌细胞体外增殖作用的影响。结果（1）5种上皮性卵巢癌细胞系中AR、ID-6Rα、gp130、IL-8RA以及IL-8RB的表达存在差异性。（2）在SKOV-3细胞，低剂量DHT（0．1～1nmol／L）作用后的前72h抑制细胞增殖，中高剂量DHT（1～100nmol／L）作用后的72、96、120h促进细胞增殖；在OVCAR-3细胞，与对照组相比，DHT作用48h时细胞增殖差异无统计学意义，作用96h和144h时才有明显的促增殖作用。DHT对这两种细胞增殖的作用具有明显的剂量依赖性和时间依赖性。（3）AR阻断剂氟他胺（flutamide，Flu）可完全阻断DHT的促增殖作用，而抗IL-6中和抗体和抗IL-8中和抗体则可部分阻断其促增殖作用。（4）ID6和ID8可促进SKOV-3和OVCAR-3细胞增殖，其促增殖作用亦具有一定的剂量依赖性和时间依赖性，且二者在SKOV-3细胞有一定的协同效应，而在OVCAR-3细胞则未见到。ID-6和ID-8诱导的促增殖作用可被其相应的中和抗体完全阻断，而不能被无关抗体即同种型羊IgG所阻断。结论雄激素促进上皮性卵巢癌生长的作用机制可能有二：一是雄激素的直接刺激作用，二是通过调节细胞因子（如ID-6和IL-8）分泌和/或其受体表达量，从而促进细胞的生长。     

雄激素调节卵巢癌细胞IL-6基因启动子活性的研究

目的探讨雄激素诱导卵巢癌细胞IL-6基因启动子活化的分子机制。方法选择SKOV-3细胞作为研究模型，应用ELISA、RT-PCR及荧光素酶检测技术观察5廿二氢睾酮（5a-dihvdrotest—osterone，DHT）对IL-6表达水平及IL-6基因启动子活性的影响，并对DHT诱导IL-6基因启动子活化的机制进行研究。结果（1）DHT可促进SKOV-3细胞IL-6分泌及相应mRNA的表达，该作用可被雄激素受体（AR）阻断剂氟他胺（flutamide，nu）完全阻断，提示DHT诱导上述作用是AR途径介导的。（2）IL-6本身能以剂量依赖性的方式增强SKOV-3细胞IL-6基因启动子的转录活性，DHT也具有与IL-6相似的作用。DHT的这种作用可被Flu完全阻断，也可被抗IL-6中和抗体部分阻断。（3）转录因子NF-IL-6、NF-xB及其亚单位pSO、p65均可诱导SKOV-3细胞IL-6基因启动子的活性。DHT不改变NF-IL-6介导的IL-6基因启动子的转录活化，而增强NF-xB（pSO＋p65）及其亚单位pSO、p65介导的IL-6基因启动子的转录活化。结论雄激素增强的IL-6基因启动子转录活性是AR途径介导的，同时有部分是通过IL-6的作用而实现。雄激素很可能通过AR与转录因子NF-xB或其亚单位pSO和p65之间蛋白-蛋白的相互作用反式激活IL-6基因启动子的活性。     

DHT对卵巢癌细胞IL-6、IL-8及其受体表达的调节作用

目的 初步探讨雄激素对卵巢癌细胞IL-6、IL-8及其受体表达的调节作用及作用机制.方法 选择兼有雄激素受体(AR)、IL-6和IL-8及其受体表达的卵巢癌细胞系SKOV-3和OVCAR-3作为研究模型,观察5a-二氢睾酮(DHT)对IL-6、IL-8及其受体表达以及NF-κB加转录的调节作用.结果 DHT可促进卵巢癌细胞IL-6、IL-8分泌及相应mRNA表达,并增强IL-6基因启动子的转录活性,DHT的上述作用可被AR阻断剂氟他胺完全阻断.DHT显著提高卵巢癌细胞NF-κB加亚单位p50、p65(RelA)mRNA的表达水平,其中对后者的作用与对IL-6、IL-8 mRNA的作用相平行.此外,DHT尚能调节IL-6、IL-8受体的表达.结论 雄激素可能通过NF-κB信号传导途径促进卵巢癌细胞IL-6、IL-8的分泌,同时对二者受体的表达也有一定的凋节作用.     

IL-4诱导THP-1细胞表达DC-SIGN的信号通路调节研究

目的 研究IL-4诱导THP-1细胞表达DC-SIGN的信号调节通路,探索DC -SIGN表达的信号调控网络.方法 以佛波脂(PMA)刺激THP-1细胞24h后加入IL-4作用48 h诱导DC-SIGN的表达,并设ERK阻断剂、NF-κB阻断剂、JAK-STAT阻断剂和MAPK阻断剂处理组.用RT-PCR检测DC-SIGN的mRNA表达,Western blot检测胞质内DC-SIGN蛋白的表达,流式细胞术检测细胞表面DC-SIGN的表达.另外,提取IL-4诱导0、10、20、30、60和120 min的THP-1细胞胞质和胞核蛋白,Western blot检测不同信号通路的信号蛋白及其磷酸化蛋白的变化.结果 IL-4可以大幅提高DC-SIGN在THP-1细胞上的表达,包括mRNA和胞膜蛋白水平.在mRNA、胞质和细胞表面蛋白表达3个水平上,ERK通路阻断剂阻断效果最好,几乎完全阻断了IL-4的诱导效果,JAK-STAT和NF-κB通路阻断剂具有部分阻断效果,而p38通路阻断剂无阻断效果.信号蛋白检测结果显示,IL-4诱导0～120 min内,胞质磷酸化ERK1/2、磷酸化STAT6以及NF-κBp65、NF-κBp50、磷酸化IKB和磷酸化AKT随时间推移浓度逐渐升高,而p38MAPK及其磷酸化蛋白浓度无明显改变.胞核内胞质磷酸化ERK1/2、磷酸化STAT6以及NF-κBp65和NF-κBp50随时间推移浓度逐渐升高.结论 ERK、JAK-STAT和NF-κB通路参与了DC-SIGN启动子的活化,其中以ERK通路为主.     

IL-34诱导肺成纤维细胞IL-6、IL-8表达机制研究

目的:探究IL-34诱导肺成纤维细胞IL-6、IL-8表达的分子机制。方法:体外培养原代人肺成纤维细胞,给予外源性重组IL-34刺激,检测IL-6、IL-8 mRNA和蛋白的变化及MAPK、PI3K-Akt、JAK等信号通路的活化;MAPK、PI3K-Akt、JAK等信号分子抑制剂预处理细胞,观察IL-34刺激IL-6、IL-8 mRNA和蛋白的变化。结果:IL-34可以诱导肺成纤维细胞中IL-6、IL-8表达上调及MAPK、PI3K-Akt、JAK、NF-κB信号通路的活化;特异性信号分子抑制剂可以逆转IL-34诱导肺成纤维细胞中IL-6、IL-8 mRNA和蛋白表达的升高。结论:IL-34可以诱导肺成纤维细胞中IL-6、IL-8表达上调,MAPK、PI3K-Akt、JAK、NF-κB等多种信号通路参与了IL-34诱导IL-6、IL-8表达的信号转导过程。     

胡椒碱抑制LPS活化的人结肠腺癌细胞SW480表达IL-8的作用机制研究

目的研究胡椒碱(piperine,PIP)对脂多糖(LPS)活化的人结肠腺癌细胞SW480表达炎症因子的调节效应及可能的作用机制。方法采用WST-1法检测PIP对SW480细胞增殖的作用,利用流式微球捕获蛋白定量技术(cytometric beads array,CBA)检测炎症因子的蛋白表达水平,以实时定量PCR(qRT-PCR)检测炎症因子mRNA的表达水平,免疫印迹法检测p38MAPK信号通路和JNK信号通路的活化水平。结果 PIP处理可剂量依赖性地抑制SW480细胞的增殖,但PIP对细胞的毒性较小;CBA检测结果显示PIP以剂量依赖性方式抑制LPS诱导的SW480细胞中IL-8的分泌;实时定量RT-PCR检测显示,LPS+PIP处理组与LPS刺激组相比,IL-8的mRNA表达水平明显下降;免疫印迹分析表明,PIP可抑制LPS诱导的p38和JNK MAPK信号通路的活化水平。结论 PIP能够抑制LPS激活的人结肠腺癌细胞SW480中IL-8的分泌从而发挥抗炎作用,其机制可能与抑制p38和JNK MAPK信号通路有关。     

内源性IL-8诱导卵巢癌细胞对顺铂与紫杉醇产生耐药的机制研究

目的探讨内源性IL-8诱导卵巢癌细胞对顺铂和紫杉醇产生耐药的机制及相关信号转导通路。方法在原有工作基础上,以2种人卵巢癌细胞系A2780(不分泌IL-8,对顺铂、紫杉醇敏感)和SKOV-3(高分泌IL-8,对顺铂、紫杉醇耐药)为研究模型,分别将正义(sense,ss)IL-8基因或反义(antisense,as)IL-8基因稳定转染至A2780细胞或SKOV3细胞,应用MTT法、Caspase-3活性测定、RT-PCR及Western blot技术等观察内源性IL-8是否影响卵巢癌细胞对顺铂和紫杉醇的敏感性,并对其作用的机制和可能的信号传导通路进行研究。结果 1)内源性过表达IL-8可诱导A2780细胞对顺铂和紫杉醇产生耐药,而抑制IL-8表达可恢复SKOV3细胞对顺铂和紫杉醇的敏感性,IL-8诱导的卵巢癌细胞化疗耐药是通过降低Caspase-3活性来实现的;2)内源性过表达IL-8可上调A2780细胞的耐药相关基因MDR1和凋亡抑制基因Bcl-2、Bcl-xL及XIAP的表达,而抑制IL-8表达可使上述基因的表达明显降低;3)Wortmannin(PI3K抑制剂)和PD98059(MEK1/2抑制剂)能分别阻断IL-8诱导下卵巢癌细胞的Akt和ERK活化及化疗耐药作用。结论 IL-8诱导的卵巢癌细胞化疗耐药可能与其上调耐药相关基因MDR1和凋亡抑制基因Bcl-2、Bcl-xL及XIAP的表达以及活化Raf/MEK/ERK和PI3K/Akt信号通路相关,提示调节IL-8表达或其相关信号通路可能是治疗耐药性卵巢癌的一种良好策略。     

自分泌IL-6经Ras/MEK/ERK、PI3K/Akt通路促进卵巢癌细胞黏附和侵袭功能的研究

目的探讨内源性IL-6表达改变对卵巢癌细胞黏附和侵袭功能的影响及相关信号转导通路。方法利用以往构建的内源性过表达IL-6的人卵巢癌A2780细胞系和内源性抑制IL-6表达的人卵巢癌SKOV-3细胞,分别采用细胞体外黏附实验、Transwell小室体外侵袭实验、免疫印迹技术等观察IL-6对卵巢癌细胞黏附、侵袭能力的影响,并对其可能的信号通路进行研究。结果与对照组相比,内源性过表达IL-6可促进卵巢癌细胞的体外黏附和侵袭功能;抑制IL-6表达则可抑制卵巢癌细胞的上述功能。过表达或抑制表达IL-6可增加或减少卵巢癌细胞磷酸化ERK、Akt的表达水平,应用ERK或Akt特异性信号阻断剂可显著抑制高表达IL-6的卵巢癌细胞黏附和侵袭作用,提示可能与其活化Ras/MEK/ERK、PI3K/Akt通路有关。结论卵巢癌细胞产生的IL-6可经Ras/MEK/ERK和PI3K/Akt通路增强自身的黏附和侵袭能力,调节IL-6表达及相关信号转导通路可能是未来临床控制卵巢癌进展的一种良好策略。     

ErbB2通过FAK-Src-MAPK信号通路诱导细胞转化和移动侵袭

目的： 探讨表皮生长因子受体2（ErbB2）诱导肿瘤转化和侵袭的分子机制。方法: 用表达ErbB2逆病毒颗粒感染FAK+/+细胞，Western印迹检测ErbB2在FAK+/+细胞中的表达，免疫沉淀检测ErbB2的功能。用Src阻断剂-PP2阻断Src，用MAPK阻断剂-UO126阻断MAPK，观察Src或MAPK被阻断后对ErbB2诱导的细胞移动和细胞转化的影响。结果: 感染后ErbB2在FAK+/+细胞中稳定表达和激活。PP2抑制ErbB2诱导的FAK磷酸化以及ErbB2诱导的细胞移动。UO126阻断ErbB2诱导的MAPK磷酸化以及ErbB2诱导的细胞锚定依赖性生存-细胞转化。结论: ErbB2通过FAK-Src-MAPK信号转导通路诱导FAK+/+细胞转化和移动。     

HLA-DQ2-restricted gluten-reactive T cells produce IL-21 but not IL-17 or IL-22

We have analyzed the production of the effector cytokines interleukin (IL)-17, IL-21, and IL-22 in gluten-reactive CD4⁺ T cells of celiac disease patients, either cultured from small intestinal biopsies or isolated from peripheral blood after an oral gluten challenge. Combining intracellular cytokine staining with DQ2-α-II gliadin peptide tetramer staining of intestinal polyclonal T-cell lines, we found that gluten-specific T cells produced interferon-γ (IFN-γ) and IL-21, but not IL-17 or IL-22, even if other T cells of the same lines produced these cytokines. Similarly, in DQ2-α-II-specific T cells in peripheral blood of gluten-challenged patients, very few stained for intracellular IL-17, whereas many cells stained for IFN-γ. We conclude that gluten-reactive T cells produce IL-21 and IFN-γ, but not IL-17. Their production of IL-21 suggests a role for this cytokine in the pathogenesis of celiac disease.     

T lymphocytes need IL-7 but not IL-4 or IL-6 to survive in vivo

The role of IL-4, -6 and -7 in the survival of T lymphocytes was studied in vivo. The decay of polyclonal populations of CD4(+) and CD8(+) T cells was monitored in thymectomized anti-cytokine receptor mAb-treated and/or cytokine-deficient mice. The lack of IL-4 or -6 did not have any detectable effect on T cell survival, but IL-7 played an important role in the survival of the naive T cell compartment, especially of naive CD4(+) T cells.     

IL-12 synergizes with IL-18 or IL-1beta for IFN-gamma production from human T cells

IL-18 is a proinflammatory cytokine that plays an important role in NK cell activation and T(h)1 response. IL-18 has a structural homology to IL-1, particularly IL-1beta. IL-18R, composed of IL-1R-related protein (IL-18Ralpha) and IL-1R accessory protein-like (IL-18Rbeta), belongs to the IL-1R family. Furthermore, IL-18R at least partly shares the signal transducing system with IL-1R. Thus, the IL-18-IL-18R system has a striking similarity to the IL-1-IL-1R system. For this reason, we regarded it important to investigate whether, like IL-18, IL-1beta synergizes with IL-12 in inducing IFN-gamma production from human T cells and plays an important role in the T(h)1 response. Here we show that IL-12 and IL-1beta synergistically induce T cells to proliferate and produce IFN-gamma without their TCR engagement. IL-12 stimulation induced an increase in the proportion of T cells positive for IL-18R. Then, IL-12-stimulated T cells responded to IL-18 or IL-1beta by their proliferation and IFN-gamma production, although levels of IL-1beta-induced responses were lower. CD4(+)CD45RA(+) T cells, although they constitutively expressed IL-18Rbeta mRNA, did not express IL-18Ralpha mRNA. Phytohemagglutinin (PHA) stimulation alone induced IL-18Ralpha mRNA without affecting the expression of IL-18Rbeta mRNA. T(h)1-inducing conditions (PHA, IL-12 and anti-IL-4) further increased this expression. We also show that T(h)1 cells but not T(h)2 cells have increased expression of IL-18R and IL-1R, and produce IFN-gamma in response to IL-18 and/or IL-1beta.     

Responses to Leishmania donovani in mice deficient in interleukin-12 (IL-12), IL-12/IL-23, or IL-18

Interleukin-12 (IL-12) orchestrates acquired resistance in intracellular Leishmania donovani infection in the liver, inducing gamma interferon and, in turn, macrophage activation and parasite killing. Nevertheless, testing in IL-18(-/-) mice compared to wild-type mice and in IL-12p40(-/-) compared to IL-12p35(-/-) mice also suggested both early-acting (IL-18) and late-acting (IL-23) antileishmanial effects independent of IL-12.     

Coimmunization with IFN-gamma or IL-2, but not IL-13 or IL-4 cDNA can enhance Th1-type DNA vaccine-induced immune responses in vivo.

As we explore the potential improvements to the current DNA vaccine strategies, it may be desirable to investigate methods to improve the level of resulting immune responses. One strategy is the use of cytokine cDNA as molecular adjuvants for DNA-based vaccines. Codelivery of these molecular adjuvants consisting of expression plasmid encoding for cytokines with DNA vaccine constructs is an effective method to modulate the magnitude and direction (humoral or cellular) of the immune responses. We have previously reported on the immunomodulatory effects of codelivering cDNA for interleukin-2 (IL-2) and IL-4 as molecular adjuvants for DNA-based vaccines. In this report, we extend these finding and compare the immunomodulatory effects of IL-2 and IL-4 with those of cDNA for prototypical Thl-type cytokine interferon-y (IFN-gamma) and Th2-type cytokine IL-13. We observed that distinct antigen-specific immune modulation can be achieved by the coinjection of IFN-gamma or IL-13 genes with DNA immunogen cassettes. We observed that IFN-gamma is a strong driver of Thl immune responses. Furthermore, in contrast to previous reports on their similarities in biologic activities, IL-13 and IL-4 cDNA coimmunizations modulated vaccine-induced immune responses differently in this model. Overall, these results further support the potential utility of this strategy as an important tool for the development of vaccines and immune therapies.     

Esculetin inhibits T cell activation without suppressing IL-2 production or IL-2 receptor expression

Esculetin (6,7-dihydroxycoumarin) was found to inhibit dose-dependently the proliferation of human T cells stimulated by PHA or phorbolester plus ionomycin. Proliferation in autologous and allogeneic MLR and generation of cytotoxic T cells under limiting dilution conditions were also suppressed, with more than 90% inhibition seen at 50 microM esculetin. The immunosuppressive effect of esculetin was not due to toxicity. Esculetin did not inhibit interleukin-2 (IL-2) production, nor did it interfere with the appearance of IL-2 receptors on stimulated T cells, as judged by immunofluorescence using anti-Tac monoclonal antibody. These results show that esculetin inhibits T-cell activation at a site distal to production of IL-2 and IL-2 receptor expression.     

Interplay between IL-2 and IL-4 in human thymocyte differentiation: antagonism or agonism

The effect of recombinant interleukin 2 (IL-2) and IL-4, as well as a combination of both lymphokines on human post-natal thymocytes at different maturation stages, was analyzed by culturing highly purified pro-T cells, pre-T cells, double-negative and double-positive thymocyte subsets in the presence of IL-2 and/or IL-4. Both IL-2 and IL-4 responsiveness are developmentally regulated in human thymocytes, since IL-2 and IL-4 responses decline with increasing thymocyte differentiation, double-positive T cells displaying far less proliferation than immature thymocytes. IL-2 and IL-4 may influence pro-T cell growth in both an antagonistic and additive fashion. At low doses, IL-4 inhibits IL-2-supported growth of pro-T cells, whereas, at higher concentrations, this inhibitory effect is masked by the ability of IL-4 to stimulate pro-T cell proliferation. In contrast to peripheral lymphocytes, IL-4 does not down-regulate the expression of the IL-2 receptor light chain on thymocytes. In pro-T cell cultures, IL-2 and IL-4 favour the differentiation of distinct cell populations, namely lymphocytes displaying preferentially a TCR alpha/beta+ and CD4+CD8- phenotype versus predominantly TCR gamma/delta+ and CD4-CD8+ cells, respectively. The effect of IL-2 dominates over that of IL-4, since the composition of cultures set up in the presence of IL-2 plus IL-4 resembles that of cells cultured with IL-2 alone. In synthesis, IL-2 and IL-4 exhibit reciprocal inter-relations in human thymocyte cultures, thus supporting the notion that these lymphokines are implicated in the complex regulation of a local cytokine network.     

Helicobacter pylori preferentially induces interleukin 12 (IL-12) rather than IL-6 or IL-10 in human dendritic cells

Dendritic cells are potent antigen-presenting cells that are present in the gastrointestinal tract and are required for the induction of a Th1 T-cell acquired immune response. Since infection with the gastric pathogen Helicobacter pylori elicits a Th1 cell response, the interaction of these organisms with dendritic cells should reflect the Th1 bias. We incubated H. pylori with cultured human dendritic cells and measured the cytokine induction profile, comparing the response to that induced by Salmonella enterica serovar Typhimurium. We found that H. pylori induced little interleukin 6 (IL-6) and essentially no IL-10 in contrast to S. enterica. However, H. pylori induced levels of IL-12 that were 30% of those induced by S. enterica, indicating a Th1 response. An isogenic cagE mutant of H. pylori lost about 50% of its IL-12-inducing ability, suggesting a role for the cag type IV secretion system in the stimulation of dendritic cells.