氧化型α1-抗胰蛋白酶对HBE细胞释放炎症因子的影响

 目的：探讨氧化型α1-抗胰蛋白酶（Ox-AT）对体外培养人支气管上皮(HBE)细胞炎症因子白细胞介素8（IL-8）和单核细胞趋化蛋白1（MCP-1）释放的影响及可能机制。方法：从人血浆中分离纯化获得天然构型AT（N-AT）,加入氧化剂获得Ox-AT;用不同浓度N-AT和Ox-AT分别作用于体外培养的HBE细胞,用ELISA方法检测不同时段培养上清液中IL-8和MCP-1的含量,同时观察NF-κB抑制剂Bay11-7082对Ox-AT引起HBE细胞炎症因子释放的影响。结果：Ox-AT可促进HBE细胞释放IL-8和MCP-1,其促进作用与Ox-AT的浓度及作用时间呈正相关;用0.5 g/L Ox-AT孵育HBE细胞4、10和24 h,其促进HBE细胞分泌IL-8和MCP-1的作用与10 μg/L肿瘤坏死因子 α（TNF-α）的作用基本一致,而 N-AT无刺激HBE细胞分泌IL-8和MCP-1的作用;Ox-AT 能显著增加NF-κB活性; Ox-AT的促炎症作用能被NF-κB抑制剂Bay11-7082抑制。结论：Ox-AT是人正常支气管上皮细胞的强致炎因子,机制可能与NF-κB信号通路激活有关。     

类糜蛋白酶抑制剂对人大肠肥大细胞类胰蛋白酶释放的影响

目的：研究类糜蛋白酶抑制剂对人大肠肥大细胞释放类胰蛋白酶的影响。方法：人大肠组织经酶消化后，细胞成份有全HBSS重新悬浮。激发过程在LP4试管中、37℃条件下完成。类胰蛋白酶水平用酶联免疫吸附试验（ELISA）方法测定。结果：促分泌剂抗IgE抗体和CI在培养15分钟和35分钟时可明显刺激人大肠肥大细胞类胰蛋白酶的释放，在相同实验体系中，类糜蛋白酶抑制剂ZIGPFM、TPCK和α1-抗胰蛋白酶无明显刺激人大肠肥大细胞释放类胰蛋白酶的作用。类糜蛋白酶抑制剂均可以剂量依赖性的方式抑制抗IgE抗体诱导的类胰蛋白酶的释放，最大浓度的ZIGPFM（1 μmol／ml）、TPCK（80 μmol／ml）和α1-抗胰蛋白酶（30 μmol／ml）可分别抑制37％、40％和36．6％的类胰蛋白酶释放。在37℃条件下同大肠细胞预培养20分钟与无预培养相比，ZIGPFM和TPCK对抗IgE抗体诱导的类胰蛋白酶释放的抑制作用略增强。Amastatin对抗IgE抗体诱导的类胰蛋白酶的释放无作用。类糜蛋白酶抑制剂均可以剂量依赖性的方式抑制CI诱导的类胰蛋白酶的释放，抑制范围在23％-35．3％。在37℃条件下同大肠细胞预培养20分钟与无预培养相比，ZIGPFM对CI诱导的类胰蛋白酶释放的抑制作用有增强，TPCK则无此特点。结论：类糜蛋白酶抑制剂可抑制人大肠肥大细胞IgE依赖性和非依赖性类胰蛋白酶的释放，提示类糜蛋白酶抑制剂可望成为炎症性肠病或其它肥大细胞相关疾病的一个新的治疗途径。     

组胺对肥大细胞激活的研究

组胺是肥大细胞和嗜碱性粒细胞内组氨酸脱羧基后产生的一种胺类物质 ,是肥大细胞和嗜碱性粒细胞脱颗粒的标志物 ,本研究通过组胺对人大肠肥大细胞进行体外干预 ,探讨组胺对人肥大细胞类胰蛋白酶释放的调节和可能的机制。结果发现 :1.组胺可诱导人大肠肥大细胞以非剂量依赖性的方式释放类胰蛋白酶 ,引起最大释放量的组胺浓度为 10 0ng/ml,比基础分泌量多出 3.5倍。组胺浓度高至 10 0 0ng/ml和 10 0 0 0ng/ml时 ,其诱导类胰蛋白酶的释放量介于组胺浓度为 10ng/ml与 10 0ng/ml之间。浓度为 10ng/ml的组胺对人肥大细胞的刺激强度与 10 μg/ml的…     

探讨肺纤维化时表达单核细胞趋化蛋白-1的主要效应细胞

目的研究凝血酶对人肺上皮细胞及正常人肺成纤维细胞释放单核细胞趋化蛋白-1（MCP-1）的调节作用。方法人肺支气管上皮细胞（normal human bronchial epithelial cells,NHBE）、人肺癌上皮细胞系A549及正常人肺成纤维细胞（normal human lung fibroblasts,NH-LF）分别培养于96孔或6孔板培养板内,凝血酶诱导4h和24h后,收集上清液及细胞裂解液。ELISA方法检测MCP-1蛋白水平;实时荧光定量RT-PCR技术检测MCP-1mRNA水平。结果凝血酶可诱导NHBE、A549及NH-LF细胞释放MCP-1,但NH-LF细胞的MCP-1释放量远远高于NHBE及A549细胞;凝血酶还可诱导NH-LF细胞mRNA表达。结论人肺成纤维细胞可能是肺内表达MCP-1的主要来源细胞,因此在肺纤维化时可能起重要作用。     

瑞舒伐他汀抑制C-反应蛋白诱导的晚期内皮祖细胞炎症因子的表达

 目的： 观察瑞舒伐他汀对C-反应蛋白（CRP）诱导晚期内皮祖细胞分泌单核细胞趋化蛋白1（MCP-1)、白细胞介素8（IL-8）、血管细胞黏附分子1（VCAM-1）及细胞间粘附分子-1（ICAM-1）的影响。方法：密度离心法获取人脐血单个核细胞并培养获得晚期内皮祖细胞。以不同浓度和不同时间CRP刺激晚期内皮祖细胞,以及将晚期内皮祖细胞用不同浓度（10-8mol/L、10-7mol/L和10-6mol/L）瑞舒伐他汀预孵育12 h后再用CRP 50 mg/L刺激,观察细胞的炎症变化。采用荧光定量PCR方法检测IL-8、MCP-1、VCAM-1和ICAM-1 mRNA表达情况,用ELISA检测细胞上清液MCP-1和VCAM-1蛋白表达情况。结果：IL-8、MCP-1、VCAM-1和ICAM-1 mRNA表达量及MCP-1和VCAM-1蛋白表达量均随CRP刺激浓度的增高逐渐增加;50 mg/L CRP不同时间刺激下IL-8、VCAM-1和ICAM-1 mRNA表达量在6 h达高峰,MCP-1则在3 h即达高峰,而MCP-1和VCAM-1蛋白水平均随CRP刺激时间增加逐渐增高。而以不同浓度瑞舒伐他汀预孵育,可以浓度依赖性地抑制CRP诱导的晚期内皮祖细胞各炎症因子的表达。结论：不同浓度、不同时间的CRP刺激可增加晚期内皮祖细胞炎症因子表达,进一步证明CRP并非仅仅为炎症标志物;瑞舒伐他汀可显著抑制CRP诱导晚期内皮祖细胞炎症因子的表达,从一个新的角度阐明了瑞舒伐他汀的作用机制。     

槲皮素对TGF-β1诱导的大鼠肾小管上皮细胞细胞外基质积聚的影响

目的：观察转化生长因子（TGF）-β₁对大鼠肾小管上皮细胞MCP-1、PAI-1和Col-Ⅰ表达的影响，并探讨槲皮素的作用。方法:以大鼠肾小管上皮细胞（NRK-52E）为研究对象，采用TGF-β₁(10 μg/L)刺激，部分实验中培养的细胞在刺激前用槲皮素(50 μmol/L)预处理90 min。MCP-1及COL-Ⅰ mRNA的表达采用RT-PCR检测。PAI-1mRNA和蛋白的表达分别采用RT-PCR和Western blotting 法检测。结果:NRK-52E 细胞在TGF-β₁刺激后MCP-1 mRNA显著上调，在2 h开始升高，8 h达高峰，呈时间依赖性；PAI-1 mRNA和蛋白的表达也显著增加；同时，TGF-β₁还显著上调Col-ⅠmRNA的表达，24 h为正常的2.4倍（P<0.05）。槲皮素预处理后，TGF-β₁诱导的MCP-1、PAI-1和Col-Ⅰ的上调表达均受到明显抑制（P<0.05）。结论:槲皮素能够通过抑制MCP-1、PAI-1和Col-Ⅰ的表达而部分逆转TGF-β₁诱导的肾小管上皮细胞细胞外基质的积聚，这可能有利于延缓肾间质纤维化的发生和发展。     

组胺对人结肠肥大细胞类胰蛋白酶释放的调节作用

探讨组胺对人结肠肥大细胞类胰蛋白酶释放的调节作用。经酶消化后获取人结肠组织肥大细胞,激发后行多种干预实验。用酶联免疫吸附试验法测定类胰蛋白酶。结果发现组胺可诱导人结肠肥大细胞释放类胰蛋白酶,浓度为100μg/L时组胺释放量最大,为基础值的3．5倍。浓度为10μg/L时对人肥大细胞的刺激强度与10mg/L的抗IgE抗体相似。组胺的作用从加样后10s开始,5min后完成。百日咳毒素和抗霉素A联合2．脱氧-D-葡萄糖可显著抑制组胺诱导人结肠肥大细胞释放类胰蛋白酶。100及1000μg/L的组胺与抗IgE抗体或离子载体钙同时加入细胞中,诱导类胰蛋白酶释放的能力低于组胺单独作用组。结论为组胺可激活人结肠肥大细胞,还以自身放大机制调节肥大细胞的脱颗粒过程。     

黄曲霉毒素G_1对体外培养HPBM增殖及TNF-α分泌的影响

目的 :研究黄曲霉毒素G1(AFG1)对体外培养人外周血单个核细胞 (HPBM)增殖及细胞TNF -α分泌的影响。方法 :采用流式细胞术 (FCM)和MTT比色法研究AFG1对HPBM增殖的影响。以双抗体夹心ELISA法检测AFG1对HPBMTNF -α分泌的影响。结果 :FCM检测结果显示 ,AFG1作用 6h ,10 0 0 μg/L处理组HPBM的增殖指数明显高于对照组。AFG1作用 2 4h ,2 0 0 μg/L和 10 0 0 μg/L浓度的AFG1可明显刺激HPBM增殖 ;回归分析结果表明 ,AFG1作用 6h和 2 4h ,AFG1浓度均与增殖指数呈正相关 (r分别为 0 5 12 2和 0 5 119,P均 <0 0 5 )。MTT比色法结果显示 ,2 0 0 0 μg/LAFG1处理HPBM的A值明显高于对照组。AFG1在 10 0 μg/L浓度下可显著抑制TNF -α分泌 (P <0 0 5 )。结论 :AFG1对体外培养HPBM的增殖有刺激作用 ,在 10 0 μg/L浓度下对HPBMTNF -α的分泌有一定抑制作用。     

MCP—1对培养的人肾小球内皮细胞表达ICAM—1的影响

目的研究单核细胞趋化蛋白 - 1(MCP- 1)对培养的人肾小球内皮细胞 (HU GEC)表达细胞间粘附分子 - 1(ICAM- 1)的影响。方法采用细胞 EL ISA法。结果 1培养的 HU GEC表面有少量 ICAM- 1表达 ,在 10 ng/ m L MCP- 1刺激后 ICAM- 1表达量增多 (P<0 .0 5 ) ,6 h即有 ICAM- 1表达增强 ,12 h达高峰 ,不同浓度的 MCP- 1(10、2 0、40 ng/ m L)刺激HU GEC18h后 ,ICAM- 1表达与对照组比较差异显著 (P<0 .0 1) ;2加入抗 MCP- 1抗体后 ,ICAM- 1表达量下降 ,与对照组比较无差异 (P>0 .0 5 )。结论 MCP- 1可刺激 HU GEC表达 ICAM- 1增加。     

金雀异黄素抑制单核细胞趋化蛋白-1诱导的人脐静脉内皮细胞凋亡

目的： 研究金雀异黄素对单核细胞趋化蛋白-1（MCP-1）诱导人脐静脉内皮细胞(hUVECs)凋亡的影响及可能机制。方法： 培养并鉴定人脐静脉内皮细胞；用不同浓度金雀异黄素（0.1 μmol、1 μmol、10 μmol、50 μmol）和终浓度为10 μg/L的MCP-1作用24 h；先用MTT比色法观察细胞存活率、流式细胞技术检测细胞DNA含量及细胞周期，观察其对hUVECs生长的影响，流式细胞技术及Western印迹法检测凋亡相关蛋白Fas、 Bcl-2、Bax的表达，探讨金雀异黄素对MCP-1诱导hUVECs凋亡干预的可能机制。结果： 金雀异黄素抑制单核细胞趋化蛋白-1诱导的人脐静脉内皮细胞凋亡，抑制效应随剂量增加而增强(P<0.01,P<0.01,P<0.01)。MTT值明显增高；凋亡细胞明显少于对照组（10 μg/L MCP-1）， Bcl-2表达明显高于对照组，Fas、Bax表达明显低于对照组。结论： 金雀异黄素能抑制单核细胞趋化蛋白-1诱导的人脐静脉内皮细胞的凋亡，抑制作用有量效相关性，抑制机制可能与下调Fas、Bax蛋白及上调Bcl-2蛋白的表达有关。     

Neutrophil defensins stimulate the release of cytokines by airway epithelial cells: modulation by dexamethasone

OBJECTIVE AND DESIGN: Neutrophils may contribute to recruiting other cells to sites of inflammation by generating chemotactic signals themselves, or by stimulating other cell types to release chemoattractants such as interleukin-8 (IL-8). Recently, we demonstrated that neutrophil-derived alpha-defensins are able to increase IL-8 expression in airway epithelial cells. In addition, it has previously been reported that neutrophil elastase-induced IL-8 synthesis was insensitive to inhibition by the glucocorticoid dexamethasone. The aim of the present study was to investigate the effect of defensins on the expression of various cytokines in cultured airway epithelial cells and to examine the effect of dexamethasone on defensin-induced cytokine synthesis in these cells. METHODS: Cultures of A549 cells and primary bronchial epithelial cells (PBEC) were stimulated with defensins either alone or in the presence of dexamethasone. Supernatants were analyzed for IL-8, ENA-78, IL-6, MCP-1 and GM-CSF by ELISA. In addition, IL-8 and ENA-78 mRNA was detected by Northern blot analysis. RESULTS: Defensins increased IL-8 expression, ENA-78, MCP-1 and GM-CSF release from A549 cells, whereas in PBEC only IL-8 and IL-6 were increased. Pre-treatment with dexamethasone significantly reduced defensin-induced IL-6, IL-8 and ENA-78 synthesis in airway epithelial cells. In addition, dexamethasone also reduced the neutrophil chemotactic activity in supernatants of these cells. CONCLUSIONS: The results from the present study indicate that defensins differentially induce cytokine secretion by A549 cells and PBEC. Glucocorticoids may interfere with the defensin-induced inflammatory process by reducing defensin-induced cytokine secretion in lung epithelial cells.     

Attenuation of human lung mast cell degranulation by bronchial epithelium

BACKGROUND: Human lung mast cells (HLMC) lie in close proximity to the bronchial epithelium in asthma and adhere with high affinity to bronchial epithelial monolayers in vitro. We investigated the consequences of this adhesive interaction on HLMC activation in response to Fc epsilon RI cross-linking. METHODS: Human lung mast cells were cultured with the bronchial epithelial cell line BEAS-2B or plastic control for either 30 min or 16 h and then activated with anti-IgE. Histamine was measured by radioenzymatic assay. RESULTS: After co-culture for 30 min, IgE-dependent histamine release from HLMC was identical on both BEAS-2B and plastic. After 16 h of co-culture, there was a marked decrease in constitutive and IgE-dependent histamine release from HLMC cultured on BEAS-2B compared with those cultured on plastic or fibronectin. In contrast, the Ca(2+)/ATPase inhibitor thapsigargin produced concentration-dependent histamine release that was significantly increased on BEAS-2B compared with plastic. IgE-dependent degranulation was not significantly affected by BEAS-2B-conditioned medium. CONCLUSIONS: BEAS-2B bronchial epithelial cells attenuate IgE-dependent but not thapsigargin-induced histamine release from HLMC. The differential effect with anti-IgE compared with thapsigargin suggests that the mechanism includes interference with the proximal Fc epsilon RI signalling pathway.     

PDTC对高糖培养大鼠肾成纤维细胞中MCP-1表达的影响

目的:探讨核因子-κB(NF-κB)抑制剂吡咯烷二硫氨基甲酸(PDTC)对高糖培养大鼠肾成纤维细胞(NRK)中单核细胞趋化蛋白-1(MCP-1)表达的影响。方法:将NRK分4组进行体外培养:(1)正常组:5.6mmol/L的葡萄糖;(2)高糖组:30mmol/L葡萄糖;(3)高糖+PDTC1组:30mmo/L葡萄糖+5μmol/LPDTC;(4)高糖+PDTC2组:30mmo/L葡萄糖+10μmol/LPDTC,分别于培养24h、48h取各组NRK采用RT-PCR检测其MCP-1mRNA表达水平,采用WesternBlot检测MCP-1蛋白表达水平。结果:与正常组相比,高糖组MCP-1mRNA和蛋白表达水平显著升高(P<0.05),不同浓度PDTC干预后,MCP-1mRNA和蛋白表达水平显著下降(P<0.05),且随PDTC浓度增大,下降更明显。结论:高糖可使NRK中MCP-1表达增高,PDTC能抑制NRK中MCP-1表达。     

抗苗勒氏管激素对人黄素化颗粒细胞激素分泌的影响

目的：探讨抗苗勒氏管激素（AMH）对人颗粒细胞激素产生分时段的影响。方法：采用人黄素化颗粒细胞原代培养，分组加入不同浓度的AMH，分时段测定细胞培养液中的雌二醇（E2）和孕酮（P）浓度。结果：细胞培养液中E2、P浓度均随培养时间延长而升高，升高幅度渐下降。随着AMH浓度的增加，颗粒细胞的E2和P分泌明显降低， AMH 5μg/L组到20 μg/L组间有剂量依赖性，AMH 50 μg/L组与20 μg/L组比较无显著差别。结论：AMH可以降低体外培养人黄素化颗粒细胞的雌、孕激素分泌，并有一定的剂量依赖性，提示AMH可以影响颗粒细胞的激素合成过程。     

In vitro models for the assessment of inflammatory and immuno-modulatory effects of the volatile organic compound chlorobenzene

An in vitro cell culture system based on an air/liquid culture technique was developed which allows a direct exposure of cells to volatile chemicals without medium coverage. For the establishment of the experimental system, chlorobenzene was used as a model compound. Chlorobenzene is a volatile organic compound which is mainly used as a solvent. Beside other adverse health effects, chlorobenzene exposure has been shown to be associated with respiratory tract irritations, Th2 differentiation, and allergic sensitizations. Human peripheral blood mononuclear cells (PBMC) and lung epithelial cells (A549) were exposed to chlorobenzene via gas phase for 20 h. Additionally, PBMC were incubated with culture supernatants from exposed lung epithelial cells. High chlorobenzene concentrations (100 g/m(3)) induced IL-8 production in A549 cells, whereby lower concentrations (10 microg/m(3)-1 g/m(3)) stimulated the secretion of the monocyte chemoattractant protein-1 (MCP-1). A direct effect of chlorobenzene on the cytokine secretion of PBMC was not found. However, if PBMC were incubated with culture supernatants of exposed lung cells, an enhanced production of the Th2 cytokine IL-13 was observed. This induction was prevented in the presence of an anti-MCP-1 antibody. Our data suggest that chlorobenzene induces the production of inflammatory mediators in lung cells. The primary chlorobenzene caused release of MCP-1 in lung epithelial cells may secondarily result in a Th2 differentiation in T lymphocytes. These findings may contribute to the understanding of how chlorobenzene mediates the development of inflammatory reactions in the airways and contributes to the development of an allergic reactivity.     

Production of matrix metalloproteinase-9 in CaCO-2 cells in response to inflammatory stimuli.

Matrix metalloproteinase-9 (MMP-9) may play an important role in the development of inflammatory bowel disease (IBD). However, the cellular source of MMP-9 in the inflamed mucosa of IBD remains unclear. Here we report that MMP-9 mRNA is expressed in CaCO-2 cells, an intestinal epithelial cell line, and that its expression is upregulated by inflammatory stimuli. Stimulation of CaCO-2 cells with interleukin-1beta (IL-1beta) or tumor necrosis factor-alpha (TNF-alpha) led to a dose-dependent increase in expression and secretion of MMP-9. In contrast, bacterial lipopolysaccharide (LPS) failed to induce expression or secretion of MMP-9, suggesting that an inflammatory reaction leading to cytokine release is a necessary step for the induction of MMP-9 release in intestinal epithelial cells. Additional studies show that induction of MMP-9 mRNA peaked at 16 h of IL-1beta stimulation, whereas expression of monocyte chemoattractant protein-1 (MCP-1) and IL-8 both peaked at 3 h of stimulation. Treatment of CaCO-2 cells with rosiglitazone, a peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist, significantly reduced secretion of MMP-9, indicating that agents that activate PPAR-gamma may have therapeutic use in patients with IBD.     

糖化白蛋白对人脐静脉内皮细胞MCP-1表达的影响及其机制研究

目的:探讨糖化白蛋白对内皮细胞中单核细胞趋化蛋白-1(MCP-1)表达的影响及其机制。方法:将人脐静脉内皮细胞(HUVECs)与不同浓度的糖化白蛋白共同培养,并用糖基化产物抑制剂氨基胍(AG)和抗氧化剂N-乙酰半胱氨酸(NAC)干预。分别用免疫细胞化学和夹心ELISA方法测定细胞MCP-1的表达,硫代巴比妥酸法和黄嘌呤氧化酶法测定细胞内丙二醛含量和超氧化物歧化酶活性。结果:糖化白蛋白促进HUVECs合成和分泌MCP-1。免疫细胞化学显示,HUVECs暴露于50mg/L糖化白蛋白后,随作用时间的延长(4 h、8 h、12h),MCP-1的表达增高(P0.01),分别为对照组的1.3、1.9和2.8倍(P0.01);糖化白蛋白能引起细胞内超氧化物歧化酶活性下降(P0.05)和丙二醛含量升高(P0.01)。氨基胍和N-乙酰半胱氨酸能抑制糖化白蛋白刺激内皮细胞表达MCP-1(P0.01),N-乙酰半胱氨酸能抑制糖化白蛋白对内皮细胞内超氧化物歧化酶和丙二醛的影响(P0.05)。结论:糖化白蛋白可刺激人类内皮细胞表达MCP-1,糖化白蛋白刺激MCP-1表达与其诱导细胞内氧化应激有关。