重组腺病毒IκBαM抑制高糖诱导的血管内皮细胞凋亡

目的 研究NF-κB在高浓度葡萄糖(高糖)诱导的ECV-304血管内皮细胞凋亡中的作用。方法 用携有NF-κB抑制物IκBα突变体的IκBαM重组腺病毒(AdIκBαM)感染ECV．-细胞,利用Western Blot、EMSA、电镜、流式细胞仪等检测方法,研究NF-κB在高糖诱导的血管内皮细胞凋亡中所起的作用,以及阻断NK-κB活性对血管内皮细胞凋亡及细胞周期改变的影响。结果 高糖能诱导ECV-304细胞IκBα的降解和NF-κB的激活,G0/G1百分比增加,S和C2／M比例下降,延缓G0/G1向S期过渡,出现细胞凋亡的形态学改变,而感染AdIκBα的ECV-304／IκBαM细胞则能加速G0/G1向S期过渡,未出现细胞凋亡的形态学改变。结论 AdIκBαM能抑制高糖诱导的ECV-304细胞NF-κB的过度活化及对ECV-304细胞的致凋亡作用,加速细胞周期转换,证实NF-κB的激活在高糖所致的内皮细胞凋亡及生长周期的改变过程中起重要作用。     

EB病毒LMP1在鼻咽癌细胞中通过IκBα的降解活化NF-κB

目的　阐明鼻咽癌细胞中EB病毒编码的潜伏膜蛋白 1(LMP1)活化核转录因子NF κB的机制。方法　利用强力霉素Dox诱导表达LMP1的鼻咽癌细胞株Tet on LMP1 HNE2为实验模型 ,首先应用免疫印迹方法测定Dox诱导后不同时相LMP1的表达动力学以及IκBs蛋白量及功能的改变。进而用间接免疫荧光法检测NF κB的亚细胞定位。最后采用瞬间共转染及报道基因活性分析分析NF κB的活性。结果　在鼻咽癌细胞Tet on LMP1 HNE2中 ,Dox处理 15分钟后LMP1的表达迅速升高并维持与较高水平直至 12 0分钟。LMP1的诱导性表达导致IκBα的磷酸化并降解 ,但IκBα蛋白总量无改变。继IκBα的磷酸化并降解 ,NF κB(P6 5 )自胞浆易位至胞核且活性升高。IκBα的显性负性突变子抑制NF κB(P6 5 )的核易位及报道活性。LMP1的诱导性表达并未引起IκBβ蛋白水平变化。结论　在鼻咽癌细胞Tet on LMP1 HNE2中 ,EB病毒LMP1通过IκBα的磷酸化并降解激活核转录因子NF κB的活性 ,并且 ,LMP1诱导的NF κB活性能被IκBα的显性负性突变子完全抑制。IκBβ在此信号传导途径中无改变。LMP1表达前后IκBα蛋白总量维持恒定可能是由于NF κB的活化迅速启动了IκBα的重头合成这一自身调节环路所致。     

腺病毒介导IκBα基因在体外培养U937细胞中的表达及效应研究

目的通过构建IκBα基因的腺病毒表达载体,并用急性相反应蛋白SAA3启动子来指导目的基因IκBα的表达,体外观察在炎性刺激后IκBα蛋白的诱导性表达特性及对NF-κB活性的调控作用,对炎症介质产生的抑制效应. 方法采用DNA重组与同源重组技术,构建含只响应病理信号的启动子-急性相反应蛋白启动子SAA3、目的基因IκBα的炎症诱导性复制缺陷型重组腺病毒载体(AdIκBα).应用AdIκBα,选择在炎症反应中具有代表意义的巨噬细胞,观察AdIκBα在体外培养巨噬细胞U937中诱导性表达IκBα (Western blot)、对NF-κB活性的调控(EMSA)及体外效应.结果①成功构建炎症诱导性IκBα表达质粒(pAdpLpl SAA3 NLS IκBα),该表达框含SAA3启动子,SV40大T抗原核定位信号(NLS),IκBα cDNA和ploy A; ② pAdpLpL SAA3 NLS IκBα质粒与pJM17同源重组,脂质体(DOTAP)介导,共转染入293细胞.PCR法筛选阳性克隆,获得重组腺病毒(Ad IκBα); ③用293细胞扩增Ad IκBα;采用反复冻融法纯化腺病毒,获得高滴度(5×1010 pfu/ml)重组腺病毒; ④体外实验,用50 MOI Ad IκBα预感染体外培养的U937细胞,再用LPS攻击后,该腺病毒诱导性表达IκBα蛋白(Western blot),且表达的IκBα能抑制NF-κB的活化(EMSA)、下调LPS攻击后TNF-α、IL-6的产生.结论该IκBα腺病毒表达载体通过调控NF-κB活性,可调控炎症介质(TNF-α、IL-6)的产生,用于调理细胞的炎症反应.     

FK228对TNFα诱导人肝癌细胞HepG2 凋亡及核因子κB活化的影响

目的 研究FK228对TNFα诱导的人肝癌细胞HepG2凋亡及核转录因子κB(nuclear factor-κB,NF-κB)活化的影响.方法 培养HepG2细胞分别用TNFα刺激和FK228+TNFα共同作用,western blot分析细胞核中NF-κBp65及其细胞浆中抑制因子I κBα的表达;用流式细胞技术测定细胞凋亡.结果 组蛋白去乙酰化酶抑制剂FK228(4～32 ng/mL)能抑制TNFα诱导的NF-κBp65的核转移,减少胞浆中IκBα的降解,且增强TNFα诱导的细胞凋亡.结论 FK228减少胞浆中IκBα降解、抑制NF-κB的活化可能是诱导HepG2细胞凋亡、发挥抗肿瘤作用的重要机制.     

NF-κB/IκB信号通路介导血管紧张素Ⅱ诱导的系膜细胞促炎性细胞因子表达

目的：探讨核因子—κB(NF—κB)／IκB信号通路在血管紧张素Ⅱ(AngⅡ)诱导的肾小球系膜细胞促炎性细胞因子表达中的作用。方法：应用核酸酶保护法检测系膜细胞肿瘤坏死因子α(TNF—α)、IL-1α和IL-1β mRNA表达；应用凝胶电泳迁移率和Western blot检测肾小球系膜细胞中NF—κB活化、p65亚基核转位以及IκBα和IκBβ的降解。结果：正常培养状态下，系膜细胞可组成型表达TNF—α和IL—1β，而不表达IL-1αmRNA，AngⅡ刺激后促炎性细胞因子表达显著上调，NF—κB特异性抑制剂2-硫代氨基甲酸吡咯烷显著抑制AngⅡ诱导的促炎性细胞因子基因表达；AngⅡ诱导系膜细胞NF—κB活化，p65核转位及胞质内IκBα和IκBα的降解。结论：AngⅡ诱导肾小球系膜细胞中促炎性细胞因子表达可能通过NF—κB／IκB信号转导通路来实现。     

核因子-κB在TNF-α诱导HL-60细胞凋亡中的作用

目的　了解白血病细胞系 HL- 60中 ,肿瘤坏死因子 - α( TNF- α)诱导的核因子 - κB( NF- κB)活化与细胞凋亡之间的关系。方法　采用脂质体基因转染技术 ,将突变的核因子抑制蛋白 ( IκBα)质粒 ( p CMV4- IκBαS32 / 36 A)转染 HL-60细胞 ,于 48h后测其瞬时表达效应。用间接免疫荧光和 Western blot技术检测转染组和非转染组 HL- 60细胞的 NF-κB活化状态 ,同时用流式细胞术和 MTT法分别检测 TNF- α对两组 HL- 60细胞的凋亡诱导及生长抑制效应。结果　TNF- α可诱导非转染组 HL- 60细胞的 NF- κB活化 ,不能诱导转染组细胞的 NF- κB活化 ,即突变型 IκBα可特异性抑制HL- 60细胞的 NF- κB活化。结论　用突变型 IκBα特异性抑制 HL- 60细胞的 NF- κB活化 ,能明显增加其对 TNF- α的敏感性     

Adenovirus-mediated overexpression of novel mutated IκBα inhibits nuclear factor κB activation in endothelial cells

Nuclear factor κB （NF-κB） overactivation, requiring phosphorylation and degradation of its inhibitor IκBα, is the basis for chronicity of airway inflammation in asthma. Based on our previous plasmid pShuttle-IκBα, carrying an IκBα gene from human placenta, we optimized a novel IκBα mutant （IκBα） gene, constructed and characterized its replication-deficient recombinant adenovirus （AdIκBαM）, and tested whether AdIκBαM-mediated overexpression of IκBαM could inhibit the NF-κB activation in endothelial cells.     

FK228对TNFα诱导人肝癌细胞HepG2凋亡及核因子κB活化的影响

目的研究FK228对TNFα诱导的人肝癌细胞HepG2凋亡及核转录因子κB(nuclear factor-κB,NF-κB)活化的影响。方法培养HepG2细胞分别用TNFα刺激和FK228 TNFα共同作用,westernblot分析细胞核中NF-κBp65及其细胞浆中抑制因子IκBα的表达;用流式细胞技术测定细胞凋亡。结果组蛋白去乙酰化酶抑制剂FK228(4～32ng/mL)能抑制TNFα诱导的NF-κBp65的核转移,减少胞浆中IκBα的降解,且增强TNFα诱导的细胞凋亡。结论FK228减少胞浆中IκBα降解、抑制NF-κB的活化可能是诱导HepG2细胞凋亡、发挥抗肿瘤作用的重要机制。     

核因子κB激活在急性胰腺炎发病中的作用

目的　探讨急性胰腺炎时核因子κB (NF κB)激活的水平 ;及其肿瘤坏死因α(TNF α)在胰腺炎发病中的作用。方法　将 6 4只Wistar大鼠分成对照组和胰腺炎两组 ,在复模后分别于1 5、3、6、12h用流式细胞术 (FCM )和酶联免疫吸附法 (ELISA)分别检测了NF κB激活的水平和TNF α蛋白表达量。同时测定血清中淀粉酶及脂肪酶含量 ,并行病理切片进行胰腺病理分级。结果　急性胰腺炎组中的NF κB激活的水平和TNF α蛋白表达量在各个时间段均有所增高 (P <0 0 5 )。在复模后 3h胰腺组织中NF κB激活的水平达到高峰 ,TNF α蛋白表达量和血清中淀粉酶及脂肪酶升高最明显 (P <0 0 1) ;胰腺组织充血、水肿明显 ,至 6hNF κB激活趋缓 ,而TNF α蛋白表达量和血清中淀粉酶及脂肪酶仍处于升高趋势 ,同时胰腺组织出现大片的出血及坏死。结论　在急性胰腺炎的发病过程中 ,NF κB的活化作为始动因子激活一系列的炎症介质 ,尤以TNF α最为明显 ,同时大量的消化酶类物质释放 ,引起胰腺组织快速的炎症反应 ,最终导致胰腺的出血和坏死     

NO对内毒素诱导的肺泡巨噬细胞核因子-κB活化和TNF -α的调节

目的 探讨一氧化氮对内毒素（lipopolysaccharide,LPS）诱导肺泡区噬细胞核因子－κB（NF－κB）活化及肿瘤坏死因子α（TNF－α）基因表达的调节。方法 用支气管肺泡灌洗法收集肺泡巨噬细胞（pulmonary alveolar Macrophages,PAM）进行培养，分正常对照组，LPS组，NO＋LPS组。用凝胶电泳迁移率改变分析（EMSA）法和ELISA法分别检测核提取物中NF－κB活性和细胞培养上清中TNF－α含量。结果 LPS组NF－κB活性和TNF－α含量在刺激24h后明显高于正常对照组（P＜0.01）；NO＋LPS组NF－κB活性和TNF－α含量均显低于LPS组（P＜0.01）。结论 LPS诱导PAM的NF－κ活化，导致TNF－α基因表达增强；NO可抑制NF－κB活化而减少TNF－α的释放。     

Inhibition of NF-κB by mutant IκBα enhances TNF-α-induced apoptosis in HL-60 cells by controlling bcl-xL expression

Backgound The aim of this study was to explore whether the inhibition of nuclear factor-κB (NF-κB)activation by mutant IκBα (S32,36→A) can enhance TNF-α-induced apoptosis of leukemia cells and to investigate the possible mechanism. Methods The mutant IκBα gene was transfected into HL-60 cells by liposome-mediated techniques. G418 resistant clones stably expressing mutant IκBα were obtained by the limiting dilution method. TNF-α-induced NF-κB activation was measured by electrophoretic mobility shift assay (EMSA). The expression of bcl-xL was detected by RT-PCR and Western blot after 4 hours exposure of parental HL-60 and transfected HL-60 cells to a variety of concentrations of TNF-α. The percentage of apoptotic leukemia cells was evaluated by flow cytometry (FCM). Results Mutant IκBα protein was confirmed to exist by Western blot. The results of EMSA showed that NF-κB activation by TNF-α in HL-60 cells was induced in a dose-dependent manner, but was almost completely inhibited by mutant IκBα repressor in transfected cells. The levels of bcl-xL mRNA and protein in HL-60 cells increased after exposure to TNF-α, but changed very little in transfected HL-60 cells. The inhibition of NF-κB activation by mutant IκBα enhanced TNF-α-induced apoptosis. Thecytotoxic effects of TNF-α were amplified in a time- and dose-dependent manner. Conclusions NF-κB activation plays an important role in the resistance to TNF-α-induced apoptosis. The inhibition of NF-κB by mutant IκBα could provide a new approach that may enhance the antileukemia effects of TNF-α or even of other cytotoxic agents.     

Effects of over-expression of ANXA10 gene on proliferation and apoptosis of hepatocellular carcinoma cell line HepG2

The effects of over-expression of ANXA10 gene on proliferation and apoptosis of hepatocellular carcinoma cell line HepG2 were elucidated.The human ANXA10 gene was subcloned into the lentiviral vector,PGC-FU,to generate the lentiviral expression vector,PGC-FU-ANXA10.The corrected ANXA10 was confirmed by endoenzyme digestion,and sequencing.Recombinant lentiviruses were produced by 293T cells following the co-transfection of PGC-FU-ANXA10 with the packaging plasmids pHelper1.0 and pHelper2.0.The resulting recombinant lentiviruses carrying ANXA10 were then used to infect human embryonic kidney epithelial cells,and lentiviral particles were produced.The ANXA10 expression in 293T cells was detected by using fluorescent microscope and Western blotting.HepG2 cells were infected,and divided into PGC-Fu-ANXA10 group,PGC-Fu group and HepG2 cell group.The changes of ANXA10 mRNA and protein expression were detected by using RT-PCR and Western blotting respectively.Flow cytometry and MTT assay were performed to examine the changes in cell apoptosis and proliferation respectively.The recombinant PGC-FU-ANXA10 vector was successfully constructed,the ANXA10 protein was detected by using Western blotting,and virus titer was 2×108 TU/mL.The recombinant lentiviruses were effectively infected into HepG2 cells in vitro and the infection efficiency was 70%.At 72 h after infection,the ANXA10 mRNA and protein expression levels in PGC-Fu-ANXA10 group were significantly higher than in PGC-Fu group and HepG2 cell group (P<0.05);the in vitro growth inhibition rate of HepG2 cells in PGC-Fu-ANXA10 group was 24.65%,significantly higher than that in PGC-Fu group and HepG2 cell group (P<0.05),but there was no significant difference between PGC-Fu group and HepG2 cell group;the apoptosis rate in PGC-Fu-ANXA10 group,PGC-Fu group and HepG2 cell group was (51.92±1.41)%,(19.00±1.12)% and (3.59±0.89)% respectively.The apoptosis rate in PGC-Fu-ANXA10 group was significantly higher than in PGC-Fu group and HepG2 cell group (P<0.05).The reco     

稳定表达人细胞色素P450 1A2的HepG2细胞的建立及其代谢效应

目的：建立稳定表达人细胞的色素P450 1A2(CYP1A2)的HepG2细胞。方法：将所克隆的野生型CYP1A2 cDNA从重组质粒pGEM-CYP1A2中用Kpn Ⅰ／BamHⅠ双酶切，并亚克隆到哺乳动物细胞表达栽体pREP9中。再将重组质粒转化感受态大肠杆菌Top10，用氨苄青霉素抗性筛选和限制酶谱鉴定。改良的磷酸钙介导的细胞转染法将重组质粒pREP9-CYP1A2转染肝癌细胞HepG2，用RT-PCR技术对转基因细胞的CYP1A2mRNA表达作了分析，并用MTT法比较转基因细胞对黄曲霉素B1(AFB1)细胞毒敏感试验。结果：与HepG2细胞相比，HepG2-CYP1A2转基因细胞表达CYP1A2 mRNA，能增强AFB1的细胞毒作用。结论：建立了稳定表达CYP1A2的转基因细胞系，可用于由CYP1A2参与的毒理学与药物代谢研究。     

表达UGT1A1重组腺相关病毒载体的构建

目的 获得表达胆红素尿苷二磷酸葡萄糖醛酸酶（UGT1A1）基因；构建UGT1A1重组腺相关病毒载体，制备腺相关病毒。方法 设计、合成引物，通过逆转录聚合酶链反应（RT—PCR）从HepG2细胞总RNA中扩增UGT1A1基因，最终连接于pAAV—MCS．双酶切、PCR鉴定阳性重组质粒。并在HEK293T细胞表达，制备高滴度重组腺相关病毒。结果 成功扩增了人类UGT1A1基因．构建表达UGT1A1基因重组腺相关病毒载体。并成功表达于HEK293T细胞。结论 本实验构建的人类UGT1A1重组腺相关病毒将为因UGT1A1活性不足导致的高胆红素血症的基因治疗奠定基础。     

Recombinant adenovirus with human indoleamine-2,3- dioxygenase and hepatitis B virus preS was constructed and expressed in HepG2 cells

Background  Indoleamine-2,3-dioxygenase (IDO) is proven to suppress hepatitis B virus (HBV) specific immune response and depletion of IDO may be a useful approach for HBV therapy. To test this concept, we constructed recombinant adenovirus with human IDO and HBV preS, which would form the basis for future in vivo experiments. 

Methods  The fragment of human IDO and HBV preS cDNA were subcloned into multiple cloning sites in an adenoviral vector system containing two cytomegalovirus (CMV) promoters. Recombination was conducted in the Escherichia coli BJ5183. The recombinant adenovirus containing hIDO gene and HBVpreS gene was packaged and amplified in 293 cells. Integration was confirmed by polymerase chain reaction as well as the quantification of viral titers. HepG2 cells were infected with the recombinant adenovirus and mRNA and protein specific for hIDO and HBVpreS was detected by RT- PCR and Western blotting respectively.

Results  The recombinant adenovirus was produced successfully. Its titer was 2.5×10⁹ efu/ml. IDO and HBVpreS mRNA as well as the encoded proteins could be found in transfected HepG2 cells, but not in control HepG2 cells.

Conclusion  The transfer of hIDO-HBVpreS with double-promoter adenoviral vector was efficient. The recombinant adenovirus with hIDO and HBV preS would provide the experimental basis for future studies.

     

Anti-tumor effect of recombinant retroviral vector-mediated human ANGPTL4 gene transfection

Angiopoietin like 4 (ANGPTL4 )isanangiopoietin relatedgenediscoveredrecently 1 3　Itsproteinisabout 6 0kDainsizeandconsistsof 4 0 6aminoacids RecentstudieshaveshownthatANGPTL4isexpressedinhumanlivertissueinthefollowingatdecreasingconcentrations :normalliver≥noncancerouslivertissue >primaryhepatocellularcarcinoma(HCC) Inaddition ,itisexpressedataveryhighlevelintheplacentamediumlevelsintheheart,liver ,muscle ,pancreas,andlung ,whilelowlevelsinthebrainandkidney 4 　ANGPTL4geneplaysarol…     

p38丝裂原激活蛋白激酶基因重组慢病毒载体的构建及其在建立人前列腺癌稳定细胞株中的应用

目的构建p38丝裂原激活蛋白激酶基因(MAPK)重组慢病毒载体并建立表达外源性p38基因的人前列腺癌稳定细胞株。方法采用限制性内切酶酶切、T4 DNA连接酶连接等方法,将EGFP/p38融合基因插入慢病毒载体pTYF-EF1α-IRES-EGFP中,构建启动子EF1α调控的EGFP/p38共表达慢病毒载体pTYF-EF1α-EGFP/p38,经酶切鉴定后,利用慢病毒三质粒系统,通过脂质体法转染包装细胞HEK 293T细胞,收集病毒上清后转导人前列腺癌DU145细胞株,经有限稀释法筛选重组EGFP/p38稳定细胞株,用Western blotting检测细胞总p38的表达,用计数法绘制细胞的生长曲线。结果经酶切鉴定,成功构建EGFP/p38重组慢病毒载体,并包装慢病毒,检测病毒悬液的滴度为4.7×106 TU/ml,利用此病毒悬液感染DU145细胞,成功筛选到EGFP/p38稳定表达细胞株,Western blotting显示该细胞株能稳定表达外源性EGFP/p38融合蛋白,这种过表达p38的细胞株的生长速度明显低于对照组。结论成功构建p38 MAPK重组慢病毒载体并建立了表达外源性p38 MAPK基因的稳定细胞株EGFP/p38-DU145,细胞内p38过表达能够抑制DU145细胞的增殖。     

p16β基因重组腺病毒质粒的构建及对喉癌细胞的作用

目的探讨野生型p16β对体外喉癌Hep-2细胞周期信号传导的干预作用。方法以重组腺病毒为载体,构建p16β的重组腺病毒AdEasy-GFP-p16β质粒,并在293细胞中包装、纯化。将已纯化的重组腺病毒AdEasy-GFP-p16β在体外转染Hep-2喉癌细胞,采用MTT实验、流式细胞术（FCM）、免疫组化、Western blot等实验手段检测Hep-2细胞的抑制／杀伤作用及其细胞周期信号、DNA含量、细胞凋亡率的变化;检测P16蛋白的表达和Hep-2细胞的超微结构变化。结果本研究成功地构建和制备了高滴度的AdEasy-GFP-p16β重组腺病毒,并高效地转移到Hep-2细胞内和表达P16蛋白,有效地抑制了Hep-2细胞的生长。被转染的Hep-2细胞被有效地阻滞在G0／G1期,提高了转染细胞的凋亡率。结论重组腺病毒AdEasy-GFP-p16β能高效感染Hep-2细胞,表达P16蛋白;有效抑制Hep-2细胞增殖;干预Hep-2细胞周期的信号传导机制和细胞周期,诱导凋亡,从而抑制肿瘤细胞增殖活性。     

大肠杆菌内同源重组法构建含mIκBα基因的重组腺病毒及其在Hep G2细胞中的表达

OBJECTIVE: To develop a rapid and efficient method for preparing recombinant adenovirus containing human mIkappaBalpha gene by homogenous recombination in E.coli. and detect its expression in Hep G2 cells. METHODS: The mIkappaBalpha gene was cloned into the shuttle plasmid pAdTrack-CMV containing green fluorescent protein (GFP) reporter gene, followed by linearization of the resultant plasmid pAdTrack-CMV- mIkappaBalpha by Pme I digestion and subsequent cotransformation into E.coli BJ5183 cells along with an adenoviral backbone plasmid pAdEasy-1. The recombinant plasmid pAd- mIkappaBalpha was selected for kanamycin resistance and confirmed by multiple restriction endonuclease analyses. Finally, the linearized recombinant plasmid was transfected into 293 cells, in which Ad- mIkappaBalpha were generated within 7 to 10 days. The virus titer in 293 cells and its infection efficiency in Hep G2 cells were detected and calculated with the aid of GFP expression. RESULTS: PCR indicated that the recombinant adenovirus contained mIkappaBalpha gene and the titer of Ad- mIkappaBalpha was 2.7x10(9) PFU/ml. With a multiplicity of infection (MOI) of 10, Ad- mIkappaBalpha could be expressed stably and efficiently in Hep G2 cells and the infection efficiency was 57% at 24 h and 100% at 48 h after transfection. CONCLUSIONS: Homogenous recombination in E.coli can efficiently and conveniently construct recombinant adenovirus containing mIkappaBalpha gene capable of amplification in 293 cells and efficient infection of Hep G2 cells. The recombinant adenovirus may serve as a good gene transfer vector for study the function of mIkappaBalpha gene and therapy for hepatocarcinoma.