T4噬菌体诱导肿瘤相关巨噬细胞向M1型再极化

观察T4噬菌体对M2型巨噬细胞向M1型再极化的诱导作用,并检测再极化的M1型巨噬细胞诱导小鼠Lewis肺癌细胞凋亡和抑制其侵袭的作用效果。方法：小鼠巨噬细胞RAW264.7经白细胞介素-4（IL-4）诱导为替代性活化巨噬细胞（M2型）,以T4噬菌体对M2型巨噬细胞再极化诱导;Real-time PCR检测IL-4诱导极化及T4噬菌体再极化后巨噬细胞中〖STBX〗IL-12、TNF-α、Arg-1、TGF-β、IL-10和iNOS〖STBZ〗基因mRNA的变化,Western blotting检测巨噬细胞内iNOS和Arg-1蛋白表达变化,ELISA法检测巨噬细胞培养上清中IL-10和IL-12的含量;流式细胞术和Transwell法分别检测T4噬菌体再极化巨噬细胞诱导小鼠Lewis肺癌细胞凋亡和抑制其侵袭的作用效果。结果：RAW264.7细胞经IL-4处理后被诱导成为M2型巨噬细胞,其〖STBX〗iNOS和IL-12〖STBZ〗 mRNA表达分别下降为对照组的1/2.5和1/6.2,而〖STBX〗Arg-1和IL-10〖STBZ〗 mRNA表达分别增加了161.2和120.3倍。M2型巨噬细胞经野生型和突变型T4噬菌体处理后,〖STBX〗IL-12、TNF-α、iNOS〖STBZ〗在mRNA和蛋白水平均明显逆转上调,〖STBX〗IL-10、TGF-β、Arg-1〖STBZ〗则明显逆转下调,呈现M1型特征;其中突变型T4噬菌体的诱导作用显著强于野生型。野生型和突变型T4噬菌体诱导M1再极化的巨噬细胞致小鼠Lewis肺癌细胞的凋亡率较M2型巨噬细胞显著增高[（35.3±2.44）%、（39.1±208）% vs （4.68±0.56）%;均P<0.01）],同时,显著抑制了肺癌细胞的侵袭能力[侵袭细胞数：（43.8±7.51）、（23.2±4.33）个 vs （1775±12.33）个;均P<0.01]。结论：T4噬菌体能够诱导M2型巨噬细胞向M1型再极化,并增强巨噬细胞诱导肿瘤细胞凋亡和抑制肿瘤细胞侵袭的能力。     

肺腺癌细胞对RAW264.7巨噬细胞分化的影响

摘 要：［目的］ 体外探究Lewis肺腺癌（Lewis lung carcinoma,LLC）细胞培养上清液对小鼠RAW264.7巨噬细胞极化的影响及其可能机制。［方法］ RAW264.7细胞按如下分组：空白对照组、IL-4处理组、LLC细胞培养上清液条件培养基（LLC-CM）培养组和TC-1细胞培养上清液条件培养基（TC-1-CM）培养组。各组培养48h后收集上清液和细胞,酶联免疫吸附测定（ELISA）检测空白对照组、IL-4组、LLC-CM组和TC-1-CM组巨噬细胞及LLC细胞和TC-1细胞培养上清液中补体C1q的含量,实时荧光定量PCR（qRT-PCR）检测巨噬细胞CD68、CD80、CD206、Arg-1、IL-10和IL-27 mRNA,Western blot检测CD68、CD80、CD206、Arg-1、JAK2、p-JAK2、STAT5和p-STAT5的表达。［结果］ 巨噬细胞经IL-4处理后,上清液中补体C1q含量较空白对照组升高（P<0.001）;与空白对照组及IL-4处理组相比,LLC-CM组巨噬细胞培养上清液中补体C1q含量明显升高（P均<0.001）。与空白对照组相比,LLC-CM组巨噬细胞CD80表达明显降低（P<0.001）,CD206、Arg-1、IL-10和IL-27表达明显升高（P均<0.001）,p-JAK2、p-STAT5（P均<0.001）含量降低。此外,LLC-CM组巨噬细胞p-JAK2、p-STAT5表达量低于IL-4处理组（P均<0.001）。［结论］ LLC细胞培养上清液可以通过抑制RAW264.7细胞JAK2/STAT5通路诱导其发生M2型极化并促进补体C1q高表达,高水平补体C1q可能参与促进RAW264.7细胞的M2型极化。     

特女贞苷对脂多糖诱导的巨噬细胞促炎反应的抑制作用及机制

目的：探讨特女贞苷(NED)抑制细菌脂多糖(LPS)诱导巨噬细胞促炎反应的机制。方法：用50μmol/L NED处理RAW264.7巨噬细胞12 h后，采用CCK-8法测定细胞活力，Annexin V-FITC/PI法测定细胞凋亡率，转录组测序分析异常基因表达，免疫荧光检测Nrf2蛋白表达定位。进一步使用100 ng/mL LPS(模型组)与不同浓度(0、12.5、25和50μmol/L)NED联合处理RAW264.7细胞干预12 h后，采用ELISA测定细胞上清液中TNF-α和IL-6含量；实时荧光定量PCR(qPCR)检测细胞TNF-α和IL-6 mRNA的表达；分别采用DCFH-DA、MitoTracker-Green和JC-1染色测定细胞中活性氧、线粒体含量和膜电位；试剂盒测定细胞内抗氧化酶活力、线粒体复合物I和III活性以及ATP合成的变化。结果：与空白对照组相比，50μmol/L NED对巨噬细胞存活和凋亡无明显影响(P>0.05)，但可抑制模型组LPS诱导促炎因子TNF-α、IL-6的表达和分泌(P<0.05)，并增强抗炎因子转录表达(P<0.05)，呈...     

温阳散结汤含药血清通过NF-κB通路调控肿瘤相关巨噬细胞极化对Lewis肺癌的影响

目的:观察温阳散结汤对 Lewis 肺癌小鼠肿瘤生长及瘤组织中巨噬细胞M2型极化的影响,并探索其调控NF-κB信号通路抑制肿瘤相关巨噬细胞M2型极化,对Lewis肺癌细胞侵袭、迁移能力的影响。方法:建立C57BL/6小鼠 Lewis 肺癌移植瘤模型,温阳散结汤干预14 d 后观察小鼠瘤重和肺转移灶,计算肺转移抑瘤率,免疫组化染色检测小鼠瘤组织中巨噬细胞M2型表面标志物 CD206 的表达;温阳散结汤灌胃SD大鼠制备含药血清,采用IL-13干预RAW264.7小鼠巨噬细胞建立巨噬细胞M2型极化模型,CCK-8法检测温阳散结汤含药血清对巨噬细胞增殖的影响,流式细胞术和Western-blot检测 CD206的表达,RT-PCR检测巨噬细胞M2型标志基因的mRNA表达,ELISA法检测细胞上清中IL-1β、IL-10、TGF-β 和TNF-α 的水平变化,Western-blot检测氧化物酶体增殖物激活受体γ（PPARγ）、核因子-κB p65(NF-κB p65)和磷酸化核因子-κB p65（pNF-κB p65）的蛋白表达;收集温阳散结汤含药血清处理的M2型巨噬细胞条件培养基,将其作用于Lewis肺癌细胞,通过Transwell侵袭迁移实验检测Lewis 肺癌细胞的侵袭和运动迁移能力。结果:温阳散结汤干预后,明显减少了小鼠瘤重和肺转移灶数,并抑制了瘤组织CD206的阳性表达（P<0.05）;温阳散结汤含药血清干预后,IL-13诱导的M2型巨噬细胞中F4/80+CD206+的细胞比例和CD206蛋白表达明显减少,MRC1、Arg1、Ym1的mRNA表达水平显著降低,细胞中TNF-α、IL-1β的含量明显升高,IL-10、TGF-β的含量明显降低,同时明显下调了细胞PPARγ、NF-κB p65、pNF-κB p65的蛋白表达及pNF-κB p65/NF-κB p65比值（均P<0.05）;温阳散结汤含药血清处理的M2型巨噬细胞条件培养基干预后,Lewis肺癌细胞迁移和侵袭细胞数明显减少（P<0.05）。结论:温阳散结汤具有抑制肺癌肿瘤生长和转移的作用,其作用机制可能与调节NF-κB通路,抑制IL-13诱导的RAW264.7细胞M2型极化,从而抑制Lewis肺癌细胞侵袭和迁移能力相关。     

两种巨噬细胞系中PKC亚型表达的差别与其抗瘤活性的比较:依赖一氧化氮的杀瘤机制

目的探讨 LPS 诱导的巨噬细胞杀瘤效应以及与 PKC 相关的分子机制。方法两种巨噬细胞系 P388D1和 RAW264.7用 LPS 刺激、或先用 PMA 长期处理下调 PKC 表达、或用 L-NAME 阻断 iNOS 后再以LPS 刺激,检测其杀伤肿瘤细胞系 P815(MTT 法)及分泌 IL-1,TNF-α(ELISA 法)和 NO(Griess 试剂)的作用;并用 Western blot 法检测 PMA 长期作用后两株细胞系中 PKC 亚型的表达。结果 LPS 刺激的 RAW264.7细胞有杀伤靶细胞的功能,而 P388D1几乎没有杀伤作用。PMA 预处理(1μg/mL,24h)后可明显抑制 LPS 诱导的杀瘤作用。因上述结果提示 PKC 在巨噬细胞杀瘤活性中可能的重要作用,比较了 PMA 处理后两株细胞 PKC 亚型的表达:Western blot 结果显示,在所检测的 PKCα,β1,β2,δ及ε5种亚型中,在 P388D1细胞均有表达,而在 RAW264.7细胞仅有 PKCα,PKCβ1,PKCδ表达;1μg/mL PMA 作用24h 后明显下调了 RAW264.7细胞 PKCα,PKCβ1和PKCδ的表达,在 P388D1则有 PKCα、PKCδ和 PKCε下调,而 PKCβ1和 PKCβ2不被下调。结合 LPS 诱导的与 PKC 活化有关的 IL-1、TNF-α及 NO 的产生,发现在 P388D1细胞几乎不产生 NO,而在 RAW264.7细胞,NO 合成酶抑制剂 L-NAME 不仅能阻断 LPS 诱导的 NO 的产生,而且明显抑制 LPS 诱导的杀瘤活性。结论 LPS 诱导的巨噬细胞杀瘤作用主要是 NO 的杀伤作用来完成而非巨噬细胞直接与瘤细胞作用所致;而该作用与 PKCβ活性密切相关。     

胃癌细胞外泌体调控M2型巨噬细胞极化及对胃癌细胞增殖和迁移的影响

目的:探究胃癌细胞外泌体调控M2型巨噬细胞极化及对胃癌细胞增殖和迁移能力的影响。方法:差速离心法提取胃黏膜上皮细胞GES-1和胃癌细胞株MGC-803、SGC-7901外泌体,透射电镜和Western blot鉴定外泌体,将U937细胞与PMA共孵育诱导U937细胞分化为巨噬细胞的同时分别与PBS、GES-1 exo、MGC-803 exo、SGC-7901 exo、IL-4孵育48 h,流式细胞术检测孵育后各组细胞CD206和HLA-DR表达,qRT-PCR检测CCL17、CXCL8、IL-10、TGF-β、TNF-α、IL-6、IL-1β表达,Western blot检测p-NF-κB、NF-κB、IκBα表达水平,将各组诱导后的U937细胞与MGC-803、SGC-7901共培养后,收集MGC-803、SGC-7901细胞,MTT检测各组细胞的增殖能力,Transwell小室法检测各组细胞的迁移能力。结果:差速离心法提取的外泌体符合外泌体的形态特征,并且在激光共聚焦显微镜下观察到外泌体可被U937细胞摄取,与MGC-803 exo、SGC-7901 exo共孵育后的U937细胞CD206显著高表达,HLA-DR低表达（P＜0.05）,CCL17、CXCL8、IL-10、TGF-β表达显著上调（P＜0.05）,TNF-α、IL-6、IL-1β表达显著下调（P＜0.05）,NF-κB磷酸化水平显著增加（P＜0.05）,IκBα表达显著增加（P＜0.05）,并且与MGC-803 exo、SGC-7901 exo诱导极化后的巨噬细胞共培养组MGC-803、SGC-7901细胞增殖和迁移能力显著增强（P＜0.05）。结论:胃癌细胞能够通过激活NF-κB信号通路促进M2型巨噬细胞极化进而诱导MGC-803、SGC-7901细胞增殖和迁移能力的增强。     

肿瘤相关巨噬细胞对鼻咽癌进展和预后的影响

背景与目的:有研究表明,在肺癌、乳腺癌等肿瘤组织中,肿瘤相关巨噬细胞(tumor-associatedmacrophages,TAMs)与肿瘤的预后呈负相关。然而在胃癌和部分结直肠癌的研究中得出了TAMs与预后呈正相关的结论。本研究旨在探讨TAMs对鼻咽癌(nasopharyngealcarcinoma,NPC)进展和预后的影响。方法:应用免疫组化技术检测60例鼻咽癌组织中TAMs标记物CD68的表达;分别培养正常巨噬细胞、鼻咽癌细胞株CNE-1和CNE-2以及肺癌细胞株95D,将同浓度的3种癌细胞株的上清液加入同量的巨噬细胞中共培养1天,6天及加入LPS活化后继续培养1天,应用ELISA技术检测共培养后TAMs释放的细胞因子TNF-α和IL-10的表达。以与肺癌细胞株95D上清液共培养后的巨噬细胞作为阳性对照;正常巨噬细胞作为阴性对照。结果:鼻咽癌组织中TAMs高密度表达者的3年无瘤生存率(85.7%)明显高于低密度表达者(56.3%)(P=0.017)。与阳性对照组比较,接受鼻咽癌细胞株CNE-1和CNE-2上清液刺激后的TAMs分泌TNF-α较少(73pg/ml,64pg/mlvs.7794pg/ml,P=0.001),经LPS活化后明显增多(6905pg/ml,6788pg/mlvs.137pg/ml,P=0.001);分泌IL-10很少(1pg/ml,1pg/mlvs.94pg/ml,P=0.002),经LPS活化后升高不明显(87pg/ml,99pg/mlvs.416pg/ml,P=0.015),与阴性对照组比较差异无显著性。结论:鼻咽癌组织中TAMs的密度与患者的预后呈正相关;与鼻咽癌细胞上清液共培养后TAMs分泌的细胞因子倾向于杀伤肿瘤细胞,促进机体的抗瘤免疫作用。     

靶向人CD70的嵌合抗原受体巨噬细胞制备及其对肾癌的杀伤作用的研究

目的:本研究旨在探讨稳定感染靶向人CD70蛋白的嵌合抗原受体巨噬细胞(chimeric antigen receptor macophages, CAR-M)对人肾癌细胞系(786-O、OS-RC-2和ACHN)的体外杀伤作用,开发靶向人CD70的肾癌细胞的新型细胞疗法。方法:将含人CD70抗体scFv片段的CAR序列插入含有GFP序列的慢病毒质粒中,制备CD70-scFV-CAR-GFP的慢病毒。通过慢病毒感染小鼠巨噬细胞RAW264.7制备CD70-CAR-M,通过流式细胞仪分选出含有绿色荧光标记的CD70-CAR-M细胞并在体外筛选稳定表达细胞株。将CD70-CAR-M细胞与不同类型的肾癌类器官按照1∶1的比例分别共培养后,利用流式细胞术检测CD70-CAR-M对肾癌细胞的杀伤作用。qRT-PCR检测CD70-CAR-M在和肾癌细胞系共培养后TNF-α和TGF-β的表达水平改变情况。结果:通过测序确认了CD70-scFV序列,并成功制备了相应的慢病毒。利用该慢病毒感染巨噬细胞RAW264.7,通过qRT-PCR技术证明CD70-CAR分子稳定表达在RAW264.7。通过和不同类型...     

二苯乙烯苷抗氧化和抗炎作用的机制研究

目的： 以小鼠巨噬细胞RAW264.7细胞为研究对象，探讨二苯乙烯苷（TSG）介导的抗氧化和抗炎作用及其调控机制。方法： 30、60和120 μmol/L的二苯乙烯苷预处理4 h，然后以1 μg/mL的脂多糖（LPS）刺激小鼠巨噬细胞（RAW264.7）12 h，并设置空白对照组、地塞米松（100 nmol/L）阳性对照和Nrf2抑制剂寒鸦子酸（brusato，50 μmol/L）干预组，其中地塞米松和brusatol预处理RAW264.7细胞4 h。观察光镜下RAW264.7细胞形态学的改变并统计其被激活比例；ELISA法检测培养液中TNF-α和IL-6的水平；通过DCFH-DA和Mito-SOX^TM荧光探针染色，流式细胞仪检测细胞内和线粒体内的ROS水平变化；免疫荧光法检测Nrf2的表达水平变化；Western blot检测核内Nrf2蛋白水平变化；Real-time PCR测定Nrf2下游抗氧化酶HO-1、SOD₂、SOD₁、CAT和GPX-1表达。结果： 与空白对照组细胞相比，LPS处理后RAW264.7细胞活化，胞体增大，形成大量伪足，培养基中TNF-α和IL-6增多。二苯乙烯苷可抑制LPS诱导的RAW264.7细胞激活，降低培养基中TNF-α和IL-6，且效果优于阳性对照药物地塞米松。同时，二苯乙烯苷可促进Nrf2核转位，并促进下游抗氧化酶HO-1、SOD₂和CAT表达，减轻细胞内ROS生成。而brusatol可通过阻断Nrf2活性抑制二苯乙烯苷的抗炎作用。结论： 二苯乙烯苷可激活Nrf2及其下游抗氧化酶的表达，具有良好的抗炎和抗氧化作用，是一种炎症相关疾病的候选药物。     

氢气联合巨噬细胞对乳腺癌细胞生长的影响

目的:探究氢气联合巨噬细胞对乳腺癌细胞生长的影响及其机制。方法:CCK8法和流式细胞术检测癌细胞的活力及凋亡情况，ELISA检测巨噬细胞分泌的细胞因子TNF-α，IFN-γ，IL-10，Western blot检测FADD、TRAF2、caspase3的表达，流式细胞术和RT-PCR分析各组巨噬细胞标志物CCR7、CD206的表达情 况。结果:氢气联合巨噬细胞使乳腺癌细胞活力降低，凋亡增加；机制方面，氢气联合巨噬细胞增加了细胞因子TNF-α，IFN-γ的分泌，上调了凋亡通路中FADD、caspase3的表达，并且促进巨噬细胞向M1极化，抑制其向M2极化。结论:氢气联合巨噬细胞能抑制乳腺癌细胞生长。     

A special linker between macrophage and hematopoietic malignant cells: membrane form of macrophage colony-stimulating factor

The membrane form of macrophage colony-stimulating factor (mM-CSF) is an alternative splicing variant of this cytokine. Although its high expression was detected in hematopoietic malignancies, its physiologic and pathologic roles in hematopoietic system have not been established. In this report, stable transfectant clones expressing mM-CSF (Namalwa-M and Ramos-M) were obtained, which showed reduced proliferation potential in vitro. Moreover, the in vivo study showed that Namalwa-M and Ramos-M exhibited enhanced oncogenicity in tumor size in nude mice model, which could be inhibited by M-CSF monoclonal antibody. A remarkable increase in infiltrating macrophage and the vessel densities was found in tumor tissues formed by lymphoma cell lines that stably expressed mM-CSF, which suggested the involvement of macrophages in this process. The in vitro results using coculture system showed that macrophages could promote Namalwa-M and Ramos-M proliferation and activate extracellular signal-regulated kinase/mitogen-activated protein kinase signal pathway. In addition, the expression of murine origin vascular endothelial growth factor, basic fibroblast growth factor, and hepatocyte growth factor was elevated in Namalwa-M formed tumor tissues. These results suggested that mM-CSF should be a positive regulator in the development of hematopoietic malignancies by abnormally activating infiltrating macrophages, which in turn promote the malignant development. Thus, mM-CSF may be a critical linker between macrophages and malignant cells in the development of hematopoietic malignancies.     

磷化铟/硫化锌量子点对小鼠腹腔巨噬细胞功能的影响

目的: 通过建立体外模型研究磷化铟/硫化锌(InP/ZnS)量子点对巨噬细胞功能的影响。方法: 以不同浓度的InP/ZnS量子点作用于小鼠腹腔巨噬细胞RAW264.7不同时间后,采用荧光显微镜观察巨噬细胞对量子点的摄取情况;用CCK-8法检测量子点对巨噬细胞增殖能力的影响;用酶联免疫(ELISA)法检测量子点及免疫原CpG寡脱氧核苷酸(CpG-ODN)对肿瘤坏死因子-α(TNF-α)和白介素-6(IL-6)分泌的影响。结果: 与阴性对照组比较,2.5、5和10 μg/mL InP/ZnS量子点处理4 h后可被巨噬细胞摄取并定位于细胞浆内;当InP/ZnS量子点浓度达到5 μg/mL以上时,作用24和48 h后细胞增殖能力随量子点浓度增加而明显下降(P<0.05和P<0.01);经量子点处理的巨噬细胞在有或无CpG-ODN的刺激下,TNF-α的分泌出现不同程度增加(P<0.01),而IL-6变化不明显(P>0.05)。结论: InP/ZnS量子点可以被巨噬细胞摄取,抑制巨噬细胞的增殖能力,并促进TNF-α的分泌。     

鸢尾素介导抗炎和抗氧化作用的机制

目的：探讨鸢尾素(irisin)介导的小鼠巨噬细胞RAW264.7抗炎和抗氧化作用的机制。方法：用200 ng/mL鸢尾素分别处理RAW264.7细胞0、24和48 h,采用实时荧光定量PCR (qPCR)检测抗炎因子(IL-10、Arg-1、CD206),抗氧化基因(HO-1、SOD2)和PPAR-γ mRNA的表达;酶联免疫吸附实验(ELISA)检测细胞上清中抗炎因子含量;试剂盒测定抗氧化酶活性;Western blot检测PPAR-γ蛋白表达;免疫荧光法检测Nrf2、PPAR-γ的表达和定位。另用200 ng/mL鸢尾素预处理细胞4 h,100 ng/mL脂多糖(LPS)刺激巨噬细胞24 h,采用qPCR检测促炎因子表达,DCFH-DA和Mito-LX染色检测活性氧(ROS)水平。进一步用PPAR-γ抑制剂T0070907(30 μmol/mL)预处理细胞4 h,200 ng/mL鸢尾素培养24 h,采用qPCR检测抗炎因子表达。结果：与对照组相比,200ng/mL鸢尾素可促进IL-10、Arg-1和CD206等抗炎因子的表达(P<0.05),并抑制LPS诱导的TNF-α和IL-6 mRNA表达升高(P<0.05),表明鸢尾素具有抗炎作用。并且200 ng/mL鸢尾素处理RAW264.7细胞4 h后Nrf2发生核转位,HO-1和SOD2表达和酶活性显著增强,GSH含量也升高(P<0.05)。此外,鸢尾素刺激下细胞内PPAR-γ的mRNA和蛋白表达升高,并发生明显核转位,PPAR-γ抑制剂T0070907可阻断鸢尾素介导的抗炎因子表达升高(P<0.05)。结论：鸢尾素通过PPAR-γ启动巨噬细胞M2型极化发挥抗炎作用,并增强Nrf2及下游抗氧化酶谱表达,有望成为炎症疾病候选治疗药物。     

Nitric oxide synthase is induced in tumor promoter-sensitive, but not tumor promoter-resistant, JB6 mouse epidermal cells cocultured with interferon-gamma-stimulated RAW 264.7 cells: the role of tumor necrosis factor-alpha

Expression of inducible nitric oxide synthase (iNOS) has been reported to be involved in certain organs of potential tumorigenesis, including the stomach and colon. The mechanisms for iNOS expression in epithelial cells, however, are not fully understood. In the present study, we investigated the role of macrophages in epithelial iNOS expression by coculturing a stimulated murine macrophage-like cell line, RAW 264.7, with either tumor promoter-sensitive (P+) or promoter-resistant (P-) JB6 murine epidermal cells. After monoculture, treatment of RAW 264.7 cells with IFN-gamma for 24 h generated a large amount of nitrite (NO2-), as reported previously, whereas no increase in NO2- concentration was observed in the IFN-gamma-treated P+ or P-subclones. Interestingly, when IFN-gamma-treated RAW 264.7 cells were cocultured with P+ but not P- cells, we observed a marked increase in NO2- concentration (30.8+/-3.6 microM), which significantly exceeded (P < 0.01) the sum of the concentrations (20.0+/-2.3 microM) added from each cell line monoculture. Western blotting analysis revealed that, after coculture, iNOS protein was up-regulated 55-fold more than the control in JB6 P+ but not in P- cells. IFN-gamma-treated RAW 264.7 cells secreted proinflammatory cytokines, including tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta. The addition of IFN-gamma-treated RAW 264.7 cell-conditioned media to P+ subclones led to a significant enhancement of NO2- formation that was diminished by the TNF-alpha-specific but not IL-1beta-specific antibody. When combined with IFN-gamma, the recombinant TNF-alpha (1-100 ng/ml) enhanced NO2- formation in JB6 P+ cells, whereas IL-1beta (1-100 ng/ml) did not. These results led us to conclude that IFN-gamma-treated RAW 264.7 cells release TNF-alpha to induce iNOS expression in promoter-sensitive JB6 cells. Thus, we propose the hypothesis that macrophages stimulate neoplastic cells with TNF-alpha via a paracrine loop to induce epithelial iNOS protein expression.     

Effect of dominant negative transforming growth factor-beta receptor type II on cytotoxic activity of RAW 264.7, a murine macrophage cell line

Transforming growth factor-beta (TGF-beta) is a potent suppressor of the immune system. In the present study, we investigated the effect of TGF-beta resistance on a murine macrophage cell line, RAW 264.7, by overexpressing a dominant negative TGF-beta receptor type II (TbetaRIIDN) construct. As expected, TbetaRIIDN-expressing RAW cells, designated as RAW-TbetaRIIDN, were resistant to TGF-beta signaling. When these cells were cocultured with the murine renal cell carcinoma cell line, Renca, a dramatic increase in apoptosis of Renca cells was observed. Simultaneously, elevated levels of inducible nitric oxide synthase (iNOS) and tumor necrosis factor-alpha (TNF-alpha) in association with IFN-gamma were detected in RAW-TbetaRIIDN cells. When the effects of TNF-alpha and iNOS were neutralized through the use of neutralizing antibody and N(G)-methyl-L-arginine, respectively, the enhanced cytotoxicity of TbetaRIIDN-RAW cells was partially reversed. Taken together, these results show that TGF-beta-resistant RAW 264.7 murine macrophage cells have increased cytotoxic activity that is in part mediated by iNOS and TNF-alpha.     

M-CSF cooperating with NFκB induces macrophage transformation from M1 to M2 by upregulating c-Jun

Increasing evidence suggests tumor-associated macrophages (TAMs) are polarized M2 subtype of macrophage that exerts pro-tumor effects and promote the malignancy of some cancers, but the concrete mechanism is not well defined. Our previous research exhibited that proto-oncogene AP-1 regulated IL-6 expression in macrophages and promoted the formation of M2 macrophages. In this study, we investigate whether extra-cellular stimulus M-CSF help this process or nuclear factor NFκB has a synergistic role in the activation state of polarized M2 subtype of macrophage. RAW 264.7 macrophage and 4T1 mouse breast cancer cells were co-cultured to reconstruct tumor microenvironment. Being co-cultured with 4T1 or its supernatant, the expression of c-Jun, the member of AP-1 family, has a dramatically increase both on the level of gene and on the protein in RAW 264.7 macrophages, but the expression of c-Fos does not increase neither on the level of gene nor on the protein. After co-cultured with 4T1, RAW 264.7 has a higher consumption of M-CSF than RAW 264.7 macrophages alone. With the stimulation of M-CSF, the mRNA of c-Jun increased significantly, but decreased remarkably after adding the anti-M-CSF. And at the same time, p50, the member of NFκB family, has a similar tendency to c-Jun. WB results suggest that with the stimulation of M-CSF, p-Jun in nuclear increases heavily but decreases after the neutralizing antibody added. Coimmunoprecipitation and immunoblotting techniques confirmed that c-Jun and p50 NFκB coprecipitated, and c-Jun protein expression is properly enhanced with rM-CSF effect. In conclusion, M-CSF induces macrophage transformation by upregulating c-Jun with a certain synergy of NFκB. Our study may present a novel therapeutic strategy against cancer.     

Eryngium foetidum suppresses inflammatory mediators produced by macrophages

Objective: This study assessed anti-inflammatory and antioxidant activities of E. foetidum leaf extract on LPS-activated murine macrophages. Methods: RAW264.7 cells were pretreated with or without E. foetidum extract for 1 h prior to incubation with LPS for 24 h. Anti-inflammatory activity was evaluated with reference to iNOS, COX-2, TNF-α and IL-6 gene expression. In addition, NO and intracellular ROS generation were determined by Griess method and fluorescence intensity and activation of MAPKs and IkB by Western blotting. Results: Prior treatment with E. foetidum leaf extract inhibited elevation of IL-6, TNF-α, iNOS and COX-2, together with their cognate mRNAs in a dose-dependent manner. NO and intracellular ROS contents were similarly reduced. These effects were due to inhibition of LPS-induced phosphorylation of JNK and p38 as well as IkB. E. foetidum ethanol extract were shown to contain lutein, β-carotene, chlorogenic acid, kaempferol and caffeic acid, compounds known to exert these bioactive properties. Conclusions: E. foetidum leaf extract possesses suppressive effects against pro-inflammatory mediators. Thus, E. foetidum has a high potential to be used as a food supplement to reduce risk of cancer associated with inflammation.