人膀胱癌bcl-2-siRNA慢病毒载体的构建及稳定转染细胞株的建立

目的 构建表达人膀胱癌bcl-2基因的小分子RNA(siRNA)的慢病毒载体并建立稳定转染细胞株.方法 根据GenBank提供的bcl-2 cDNA序列,设计3条针对bcl-2 siRNA序列,分别构建pSIH1-H1-copGFP重组质粒.筛选出最有效沉默靶基因的siRNA后,将携带目的 序列的慢病毒载体转染到293T细胞中,感染膀胱癌细胞株T24,建立稳定转染细胞株.结果 设计的针对bcl-2的序列中第3条的抑制效果最好,下调59.0%.以此目的 序列构建稳定转染细胞株,对bcl-2 mRNA抑制率达65.6%,对bcl-2蛋白的抑制率高达74.5%.结论 成功构建表达人膀胱癌bcl-2-siRNA的慢病毒载体,它能有效沉默bcl-2基因在膀胱癌细胞株T24中的表达并建立了稳定转染细胞株.

Abstract：

Objective To obtain small interfering RNA (siRNA) sequences that can stably block the expression of bcl-2 in the bladder cancer cells, construct the bcl-2-siRNA lentiviral vector and establish a stably transfected cell line. Methods According to genetic information, 3 siRNA targeting bcl-2 were designed. The corresponding pSIH1-H1-copGFP recombinant plasmids were constructed. After the most effective siRNA was achieved, the shuttle plasmid pSIH-bcl-2-siRNA with lentiviral packaging plasmid was mixed, and 293T cells were transfected. Virus solution was collected to infect T24 cells and a stably transfected cell line was established. Results The third siRNA sequence, located in bcl-2 1210-1228, showed the best gene silencing effect as 59. 0%. The lentiviral vector was constructed successfully and the inhibition ratio was 65. 6% for bcl-2 mRNA and 74. 5% for bcl-2 protein. Conclusion It is successful to obtain bcl-2-siRNA lentiviral vector that can stably block the expression of bcl-2 in the bladder cancer cell line T24 and establish a stably transfected cell line which provides foundation for further experimental studies on the function of bcl-2.     

c-myc基因慢病毒载体的构建及其意义

目的 构建携带c-myc基因野生型及T58A突变型的慢病毒载体.方法 应用聚合酶链反应(PCR)方法 扩增c-myc野生型及T58A突变型基因,利用Gateway技术构建携带绿色荧光蛋白(GFP)基因的慢病毒载体,经PCR及基因测序鉴定后,转染293FT包装细胞,产生相应慢病毒,测定其滴度.结果 PCR和测序证实,构建分别携带c-myc野生型及T58A突变型基因的慢病毒载体,并包装慢病毒,病毒滴度测定结果　分别为6.10 × 107、5.65×107 TU/ml.结论　成功构建含有c-myc野生型及T58A突变型基因的慢病毒载体并包装出具高效感染力的慢病毒颗粒.

Abstract：

Objective To construct a lentiviral vector with c-myc gene, including wild type and mutation type. Methods The lentiviral vector with green fluorescent protein (GFP) was constructed by polymerase chain reaction (PCR) and gateway technology and identified by PCR and gene sequencing,then transfecte dinto the package cells 293FT by lipofectin to produce mature lentivirus. The virus titer was measured. Results According to PCR and gene sequencing, the myc-lentiviral vectors were successfully constructed with the virus titer being 6. 10 × 107 ( wild type) and 5.65 × 107 ( mutation type) TU/ml, respectively. Conclusion The myc-lentiviral vector was successfully constructed and efficient lentivirus particles were packaged.     

Cox7a2荧光载体构建及其对小鼠支持细胞细胞色素C氧化酶活性的影响

目的 构建pEYFP-C1-Cox7a2表达载体,研究其在小鼠睾丸支持细胞(TM4)中的表达及对细胞色素C氧化酶(COX)活性的影响.方法 应用RT-PCR方法从TM4细胞克隆Cox7a2,利用BamH I和EcoR I酶切位点将Cox7a2克隆到pEYFP-C1载体,经酶切、测序及蛋白印迹等技术进行鉴定,并将重组质粒pEYFP-C1-Cox7a2转染TM4细胞后6、12、24、48 h,采用分光光度计测定COX活性.结果从TM4细胞克隆到Cox7a2基因完整的编码序列,大小为252 bp.构建pEYFP-C1-Cox7a2表达载体,经酶切、测序鉴定证实克隆正确,转染TM4细胞的效率达70%,融合蛋白表达产物相对分子质量为37 000.重组质粒转染后6、12、24、48 h时COX活性分别为(0.642±0.051)、(0.542±0.049)、(0.311±0.021)和(0.216±0.010)U/mg,不转染组和转染空载体组分别为(0.714±0.064)、(0.653±0.031)U/mg.与不转染组相比,重组质粒转染后12、24、48 h组COX活性显著降低(P＜0.05).结论重组质粒pEYFP-C1-Cox7a2 载体成功构建.Cox7a2基因对TM4细胞COX活性具有抑制作用,可能对调控COX活性发挥重要作用.

Abstract：

Objective To construct Cox7a2 fluorescent vector and study its effect on cytochrome C oxidase (COX) activity in mouse Sertoli cell line TM4. Methods The coding region of Cox7a2 was amplified from mouse Sertoli cell line TM4 by RT-PCR. The PCR product was inserted into pEYFP-C1 vector with BamH I and EcoR I restriction site, and confirmed by DNA sequencing. The recombinant fusion protein vector was amplified by transforming into DH5a and transfected into TM4 cells. The protein expression was identified by Western blot. COX activity was measured by spectrophotometer 6, 12, 24 and 48 h after the transfection of recombinant vector into the TM4 cell line. Results The entire coding sequence of Cox7a2 was cloned with 252 bp length. Plasmid pEYFP-C1-Cox7a2 vector was constructed and the positive clones were verified by restriction enzymes digestion and DNA sequencing. The transfection efficiency of the TM4 cell line was about 70% and 37000 D fusion protein was obtained. The COX activities were (0.642±0.051), (0.542±0.049), (0.311±0.021) and (0.216±0.010) U/mg 6, 12, 24 and 48 h after the transfection of recombinant vector in the TM4 cell line. Meanwhile, the COX activities were (0.714±0.064) and (0.653±0.031) U/mg in non-tranfected and naked vector group respectively. Compared with the non-tranfected group, COX activity decreased significantly 12, 24 and 48 h after the transfection. Conclusions The recombint plasmid vector was successfully constructed. Cox7a2 gene has an inhibiting effect on COX activity and may play an important role in the regulation of COX activity in mouse Sertoli cell line TM4.     

短发卡RNA稳定沉默FOXM1对肝癌细胞体外生长的影响

目的 探讨短发夹RNA(short hairpin RNA,shRNA)表达载体稳定沉默叉头框M1(forkhead box M1,FOXM1)基因对人肝癌细胞体外生长的影响.方法 构建针对人类FOXM1mRNA的不同干扰靶点的4个shRNA表达载体,选择干扰效果最佳的表达载体和阴性对照质粒转染人肝癌细胞QGY-7703,用新霉素(G418)筛选稳定转染的克隆.用四甲基偶氮唑盐(MTT)比色法和平板克隆形成实验检测FOXM1基因沉默前后肝癌细胞体外生长能力的变化.用Annexin V-APC/PI双染法检测细胞凋亡.结果 不同人肝癌细胞株中普遍表达FOXM1蛋白.4个shRNA表达载体中,shRNA-1026表达载体的干扰效果最佳,对FOXM1 mRNA和蛋白表达水平的抑制率分别为38.5%和53.2%.用shRNA-1026稳定沉默FOXM1基因后,QGY-7703细胞增殖受到抑制,培养48、72和96 h后,沉默组的吸光值均显著低于对照组(分别t=10.830,3.578,5.734,均P＜0.05);沉默组的克隆形成能力较对照组显著降低(t=5.336,P＜0.05),而细胞凋亡较对照组显著增加(t=6.827.P＜0.05).结论 shRNA表达载体稳定沉默FOXM1基因抑制肝癌细胞的生长.

Abstract：

Objective To evaluate the effect of sustained silencing Forkhead box Ml (F0XM1) gene by short-hairpin RNA (shRNA) expression vector on cell growth of hepatocelluar carcinoma (HCC) in vitro.Methods Four shRNA expression vectors targeting different sequences of human F0XM1 mRNA were constructed.The expression vector with the best interfering effect and the negative control plasmid were used to transfect HCC cell line QGY-7703, stably transfected cell clones were selected by neomycin (G418).Cell growth was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and colony formation was assessed by clonogenic assay.Cell apoptosis was detected by double staining with APC conjugated Annexin V and PI.Results F0XM1 protein was detected with different levels in all these studied human cell lines.The expression vector shRNA-1026 exhibited excellent interference effect after transient transfection, which showed 38.5% and 53.2% reduction of FOXM1 mRNA and protein level respectively.The growth of QGY-7703 cells was inhibited after stable inhibition of FOXM1 expression by shRNA-1026, which was indicated by decreased absorbance value of the test group after culture for 48, 72 and 96 h compared to control group (t = 10.830,3.578 and 5.734 respectively, P ＜ 0.05).Stable inhibition of F0XM1 also led to reduced colony formation ( t = 5.336, P ＜ 0.05 ) and increased apoptosis of QGY-7703 cells in comparison to control cells (t = 6.827, P ＜ 0.05 ).Conclusions Stable silencing F0XM1 gene by shRNA suppresses the growth of HCC cells in vitro.     

Radioprotective effects of the expression of FLT3 ligand regulated by Egr-1 regulated element on radiation injury of SCID mice

Objective:In order to explore the radioprotective effects of the expression of hematopoietic growth factors regulated by radio-inducible promoter on radiation injury. Methods:The human FL (Flt3 ligand) cDNA and EGFP (enhanced green fluorescent protein) cDNA were linked together with IRES and then inserted into the eukaryotic expression vector pCI-Egr, which was constructed by substituting CMV promoter in pCIneo with the Egr-1 promoter (Egr-EF). The vector was transferred into human bone marrow stromal cell line HFCL by lipofectin. The transduced cell clones (HFCL/EF) had been selected by the addition of G418. The cells were exposed to γ-radiation by 60 Co source for 0.5-20Gy. The expressions of transduced cells were detected with FACS, Northern blot ELISA and CFU assay. The HFCL/EF and CD34+ cells from human umbilical cord blood were one after the other transplanted i.v. into sublethally irradiated severe combined immunodeficient (SCID) mice. The white blood cell amount in peripheral blood and human cell engrafted in recipent mice were detected by flow cytometry and CFU-GM etc. Results:The activity of EGFP in transduced cells increased by 3.1 fold as compared to non-transduced cells at 18h after exposure to 2.5Gy. The amounts of secreted FL in serum-free supernatants of Egr-EF increased by 605.46±107.21pg/ml, which were significantly higher than the control group (214.45±35.61pg/ml). The effects of FL in HFCL/EF cultural supernatants on expansion of CD34+ cells derived from cord blood in the presence of SCF, IL-6 and IL-3 were also studied. The results showed that at day 10 of culture the number of CD34+ cells increased by 173. 09±11.58×103/ml, which was significantly higher than that of non-radiation group(68. 04± 13. 73 × 103/ml). It showed that radiation can enhance the ability of the supernatants containing FL of HFCL/EF to expand early hematopoietic progenitor cells and protect hematopoietic cells from radiation-injury effects. The HFCL/EF and CD34+cells from human umbilical cord blood were one after the other transplanted i. v. into sublethally irradiated severe combined immunodeficient (SCID) mice. In contrast to two control groups (HFCL and HFCL/F), HFCL/EF (the Egr-1 regulatory element-drived expression of FL gene therapy) resulted in a proportionally obvious increase in the number of the white blood cell at early stage after radiation, while no significant differences were found for CD45+ 、CD34+ cells in bone marrow cells. In contrast to two control groups (HFCL and HFCL/F), HFCL/EF (the Egr1 regulatory element-drived expression of FL gene therapy) resulted in a proportionally obvious increase in the number of the white blood cell at early stage after radiation, without significant differences being found for CD45+、CD34+ 、CFU-GM and marrow nucleared cells in bone marrow cells. Conclusions:The results suggested both in vivo and in vitro use of the gene therapy of FL gene regulated by Egr-1 promoter could protect hematopoiesis from irradiation-induced damage.     

靶向Survivin的siRNA联合吉西他滨抑制胰腺癌细胞增殖

Objective To construct the siRNA eukaryotic expression vector targeting Survivin gene, and investigate the chemotherapy sensitivity of pancreatic cancer line Panc-1 treated by gemcitabine. Methods The siRNA eukaryotic expression vector targeting Survivin gene was constructed. Panc-1 cells were transfected with negative control vector or siRNA vector and selected by G418, and the cell growth curve was drawn. The expression of Survivin mRNA and protein was detected by RT-PCR and Western blot respectively. Panc-1 cells or transfected cells were treated with gemcitabine for 24 h,and then the growth inhibition rate was measured by MTT assay, and cell apeptosis rate was measured by flow cytometry. Results The result of endonuclease digestion and DNA sequencing revealed that the recombinant plasmid psiRNA-Survivin was constructed successfully. Survivin mRNA and protein levels were reduced by 79.2% and 83.6% respectively in stably transfected Panc-1 cells as compared with control group, and the cell growth curve was much smoother, and the growth inhibition rate [ ( 24.6±4.5 ) % / (38.7±5.2 ) % ] and apoptosis rate of these cells [ ( 16.7±2.5 ) %/( 26.8±3.4 ) % ] were significantly increased after treatment by gemcitabine (P < 0.05 ). Conclusion The constructed siRNA eukaryotie expression vector targeting Survivin could decrease the Survivin expression,inhibit the growth of Panc-1 cells significantly,and increase the chemotherapy sensitivity to gemcitabine.     

靶向Survivin的siRNA联合吉西他滨抑制胰腺癌细胞增殖

Objective To construct the siRNA eukaryotic expression vector targeting Survivin gene, and investigate the chemotherapy sensitivity of pancreatic cancer line Panc-1 treated by gemcitabine. Methods The siRNA eukaryotic expression vector targeting Survivin gene was constructed. Panc-1 cells were transfected with negative control vector or siRNA vector and selected by G418, and the cell growth curve was drawn. The expression of Survivin mRNA and protein was detected by RT-PCR and Western blot respectively. Panc-1 cells or transfected cells were treated with gemcitabine for 24 h,and then the growth inhibition rate was measured by MTT assay, and cell apeptosis rate was measured by flow cytometry. Results The result of endonuclease digestion and DNA sequencing revealed that the recombinant plasmid psiRNA-Survivin was constructed successfully. Survivin mRNA and protein levels were reduced by 79.2% and 83.6% respectively in stably transfected Panc-1 cells as compared with control group, and the cell growth curve was much smoother, and the growth inhibition rate [ ( 24.6±4.5 ) % / (38.7±5.2 ) % ] and apoptosis rate of these cells [ ( 16.7±2.5 ) %/( 26.8±3.4 ) % ] were significantly increased after treatment by gemcitabine (P < 0.05 ). Conclusion The constructed siRNA eukaryotie expression vector targeting Survivin could decrease the Survivin expression,inhibit the growth of Panc-1 cells significantly,and increase the chemotherapy sensitivity to gemcitabine.     

人PPFP基因的重组慢病毒载体的构建和表达

目的 构建含人PAX8/PPARγ/融合基因(PPFP)基因重组慢病毒载体并检测其表达性能.方法 从已构建好的含PPFP的质粒克降模板PEGFP-C-PPFP中,利用聚合酶链反应(PCR)方法钓取目的 基因PPFP,将该基因克隆到慢病毒载体表达质粒pGC-FU(含Flag基因)中,得到重组的pGC-FU-PPFP,通过PCR、酶切、测序和分析比对验证PPFP基因后,将pGC-FU-PPFP质粒和包装质粒pHelper1.0、pHelper2.0共同转染人胚胎肾上皮细胞株293T细胞,获得携带PPFP基因和Flag基因的重组慢病毒,收集并浓缩病毒上清液,测定重组病毒的滴度.通过Western blot鉴定PPFP-Flag融合蛋白在靶细胞内的表达进一步验证目的 基因在靶细胞中的表达.结果 经PCR扩增获得2591 bp的目的 基因片段,构建的重组质粒经PCR、酶切及测序和分析比对鉴定正确;该质粒与包装质粒共转染293T细胞获取的慢病毒滴度达3.5×10~7转导单位TU/ml;感染的293T细胞,Western blot结果显示条带大小为90 KDr,可判断目的 基因PPFP在293T细胞中表达.结论 成功构建PPFP基因慢病毒载体质粒pGC-FU-PPFP,并建立慢病毒过表达系统.     

HyTK基因逆转录病毒重组质粒的构建及其在PA317细胞中的高表

目的:为开展逆转录病毒介导的HyTK基因治疗恶性肿瘤奠定实验基础。方法:利用逆转录病毒载体与潮霉素磷酸转移酶和单纯疱疹病毒胸腺嘧啶核苷激酶的融合基因(HyTK)连接构建重组质粒pL(HyTK)SN,应用新一代的非脂质体基因转导系统FuGENETM6将构建的pL(HyTK)SN导入Ψ2单嗜性包装细胞并获得瞬间表达,继而再转染PA317双嗜性细胞。结果:获得高滴度重组病毒,上清逆转录病毒滴度为5.4×106cfu/ml。结论:所构建的HyTK基因可用于治疗恶性肿瘤。     

中国人肠道产甲酸草酸杆菌frc基因的分离及其在真核细胞中的表达

目的：探讨中国人肠道产甲酸草酸杆菌甲酰辅酶A转移酶基因（frc）的分离、克隆和鉴定。方法：提取中国人肠道产甲酸草酸杆菌的基因组DNA,利用PCR技术扩增frc基因片段并克隆入真核表达载体pEGFP—C1,重组质粒命名为pEGFP—frc,通过限制性内切酶酶切电泳和测序鉴定插入片段。将pEGFP—frc通过脂质体转染293细胞,通过逆转录PCR（RT—PCR）和蛋白印迹（Western blot）分别从mRNA和蛋白水平检测frc基因在真核细胞中的表达。结果：中国人肠道产甲酸草酸杆菌fre基因全长1287bp,存在53个碱基和4个氨基酸残基的变异,与GenBank中的frc基因的碱基序列的同源性为95．88％,氨基酸残基序列的同源性为99．07％。转染293细胞后24-72h,可观察到明亮的绿色荧光,RT—PCR和Western blot分别从mRNA和蛋白水平上检测到frc基因在真核细胞中的表达。结论：中国人肠道产甲酸草酸杆菌中可以分离出frc基因;中国人肠道产甲酸草酸杆菌frc基因存在一定的变异;frc基因可在真核细胞293细胞中表达。     

中国人肠道产甲酸草酸杆菌oxc基因的克隆及其在真核细胞中的表达

目的 观察中国人肠道产甲酸草酸杆菌(Ox.F)草酰辅酶A脱羧酶基因(oxc)的分离、克隆及其在293细胞中的表达.方法 提取中国人肠道Ox.F的基因组DNA,PCR扩增oxc基因片段并克隆入真核表达载体pEGFP-C1,通过限制性内切酶酶切电泳和测序鉴定基因片段.将重组质粒脂质体转染至293细胞,利用RT-PCR和Western blot分别从mRNA和蛋白水平检测oxc基因在真核细胞中的表达.结果 中国人肠道产甲酸草酸杆菌oxc基因全长1707 bp,与Gene Bank中的序列比较,碱基序列的同源性为93.61%,氨基酸残基序列的同源性为97.18%.重组质粒转染293细胞后24～48 h,可观察到明亮的绿色荧光,从mRNA和蛋白水平上可以检测到oxc基因在真核细胞中的表达.结论 中国人肠道产甲酸草酸杆菌中可以分离出oxc基因;中国人肠道产甲酸草酸杆菌oxc基因存在一定的变异;oxc基因可在真核细胞293细胞中表达.     

shRNA慢病毒表达载体对人结肠癌细胞CXCR7表达的影响

目的 探讨CXCR7的shRNA慢病毒表达载体对人结肠癌细胞HT-29 CXCR7表达的影响.方法 设计CXCR7的3条siRNA的靶点序列,合成含干扰序列的双链DNA发卡结构shRNA,分别与双酶切后的plVTHM载体连接,构建3种重组穿梭质粒plVTHM shRNA1,plVTHM shRNA2和plVTHM shR-NA3,并转化于DH5α感受态细胞,Amp筛选阳性克隆,抽取质粒行酶切鉴定并测序.分别将3种重组质粒与慢病毒包装质粒共转染293T细胞,生产慢病毒颗粒,并检测病毒滴度.将3种重组慢病毒及阴性对照病毒分别感染人结肠癌细胞HT-29,实时定量PCR和Western blot分别检测CXCR7 mRNA和蛋白的沉默效果.结果 酶切鉴定及测序结果 证实3种慢病毒载体均包装成功,滴度分别为6×107 TU/mL,4×107 TU/mL和5×107 TU/mL.感染HT-29后,CXCR7 mRNA及蛋白的表达量均较阴性对照组和未感染组明显降低(P＜0.05);其中以LV-CXCR7 shRNA-2和LV-CXCR7 shRNA-3作用显著,mRNA表达分别下调72%和67%,蛋白表达下调68%和55%(P＜0.05);而阴性感染对照组和未感染组相比差异无统计学意义(P＞0.05)结论 成功构建了3种CXCR7 shRNA慢病毒表达,可有效下调HT-29细胞CXCR7mRNA和蛋白的表达,其为进一步研究以CXCR7为靶点的结肠癌基因治疗提供稳定转染细胞的载体奠定基础.     

可诱导共刺激分子与人IgG Fc融合蛋白诱导同种免疫低应答的体内外实验

目的 探讨真核表达人可诱导共刺激分子(ICOS)与人IgG Fc融合蛋白(ICOS-Ig融合蛋白)在体内外对同种免疫应答的影响.方法 构建ICOS-Ig融合蛋白表达载体,在CHO细胞中表达并纯化ICXIS-Ig融合蛋白.以Balb/c小鼠脾细胞为反应细胞,经Co60照射灭活的(257BL/6小鼠脾细胞为刺激细胞,进行初次混合淋巴细胞反应(MLR),MLR体系中分别加入50μ,/ml IOOS-Ig融合蛋白(ICOS-Ig组)或对照IgG(IgG组),采用氚标记胸腺嘧啶脱氧核苷(3H-TdR)掺入法检测反应细胞的增殖情况,酶联免疫吸附试验(ELSA)检测培养上清液中自细胞介素(IL)2、4、10以及γ干扰素(IFN-γ)的含量.收集初次MLR细胞,与灭活的C57BL/6小鼠脾细胞或C3H小鼠脾细胞共培养,进行再次MLR,检测指标同初次MLR.以Co60照射Balb/c小鼠,经尾静脉输注用羟基荧光素二醋酸盐琥珀酰亚胺脂(CFSE)标记的C57BL/6小鼠脾细胞,每天腹腔注射ICOS-Ig融合蛋白0.2 mg(IOOS-Ig组)、IgG(对照IgG组)或环孢素A(CsA组),3 d后取Balb/c小鼠脾细胞,流式细胞仪测定CFSE荧光强度以判断同种T淋巴细胞的体内增殖情况.结果 初次MLR显示,ICOS-Ig组同种T淋巴细胞活化增殖的抑制率为(58±8)%,其培养上清液中IFN-γ的水平明显高于IgG组(P<0.05).再次MLR显示,IOOS-Ig融合蛋白能特异性抑制C57BL/6小鼠脾细胞所致的细胞增殖,抑制率为(42±8)%,IL-4和Ⅱ-10的分泌受到抑制,而IFN-γ7的分泌增加;ICOS-Ig融合蛋白并不抑制第三方细胞所致的细胞增殖.体内实验显示,ICOS-Ig组和CsA组的CFSE荧光强度明显强于空白对照组和对照IgG组(P<0.05),而联合处理组CFSE荧光强度强于ICOS-Ig组和CsA组(P<0.05).结论 ICOS-Ig融合蛋白在体内外均可抑制同种T淋巴细胞的活化增殖,且这种作用具有特异性.     

视黄醇类核内受体α基因慢病毒表达载体构建

目的 通过构建大鼠视黄醇类核内受体-α(RXR-α)基因慢病毒表达载体,获得可供转染的滴度.方法 大鼠RXR-α基因序列进行聚合酶链反应(PCR)扩增,与经AgeI酶切后的pCC-FU-3FLAG载体连接产生慢病毒载体表达质粒pGC-fu-3flag-Rxra,转化DH5α,PCR筛选阳性克隆,片段长为411bp.测序并转入293T细胞Western blot鉴定,90 KDr处有特征条带.将pGC-fu-3flag-Rxra、pHelper 1.0、pHelper 2.0三质粒共转染293T细胞,包装成慢病毒,测病毒滴度,1.00E-04μl组和Control组的Ct值存在差异(2.775).结果 DNA测序及Western blot鉴定证实构建的大鼠RXR-α基因慢病毒表达载体pGC-fu-3flag-Rxra正确,浓缩慢病毒悬液滴度为2×108TU/ml.结论 成功构建携带大鼠RXR-α基因的重组慢病毒表达载体.     

慢病毒介导的RNA干扰沉默Wip1基因对人脑胶质母细胞瘤细胞生长的影响

目的 构建人Wip1基因的RNA干扰(RNAi)慢病毒载体,有效沉默人胶质瘤U251细胞的Wip1基因并观察其对细胞生长的影响.方法 设计并合成3条Wip1基因特异性RNAi靶序列,构建到慢病毒pFU-GW-iRNA载体中.慢病毒包装转染HEK293T细胞,获得病毒上清并测定其滴度;感染U251细胞,实时定量聚合酶链反应(PCR)及Western blot鉴定RNA干扰效率;筛选出基因沉默效率最高的慢病毒感染U251细胞,CCK-8法检测细胞的增殖,Western blot检测RNA干扰后的bcl-2蛋白表达.结果 PCR扩增和测序表明成功构建Wip1慢病毒干扰载体,病毒载体包装获得的病毒上清滴度在3×10~8～8×10~8 TU/ml.可以有效地沉默U251细胞中Wip1基因的表达,构建的RNAi慢病毒载体感染U251细胞后Wip1基因的mRNA表达量同对照组比较分别为36.3%、32.9%、23.8%.稳定Wip1 RNA干扰后的U251细胞4 d后细胞增殖能力下降35.1%.结论 慢病毒介导的RNA干扰可以高效稳定地沉默基因表达,Wip1基因促进了U251细胞的增殖.     

靶向性蛋白激酶B1和环氧合酶-2 shRNA腺病毒载体的构建和在人胃癌细胞的表达

目的 构建靶向性蛋白激酶B1(PKB1/Akt1)和环氧合酶-2(COX-2)的短发夹RNA(shRNA)腺病毒载体,观察其在人胃癌细胞株SGC-7901中的表达.方法 利用同源重组技术构建重组腺病毒载体pGSadeno-Akt1+COX-2(pGSadeno-A+C),经酶切及测序鉴定后转染人胚肾细胞HEK293包装成为重组rAd5-A+C腺病毒,并测定病毒的滴度.体外转染人胃癌细胞株SGC-7901后,Real-time PCR和蛋白印迹分别检测Akt1和COX-2 mRNA和蛋白质的表达.结果 成功构建rAd5-A+C重组腺病毒,测定包装的病毒滴度为1.0×1010pfu/ml.转染组Akt1和COX-2 mRNA表达明显下调,其△Ct值分别是(12.26±0.05)和(5.41±0.09),比rAd5-HK空载组(10.63±0.02)、(3.75±0.08)和对照组(10.57±0.02)、(3.73±0.08)增高(P<0.01),而空载组和对照组比较ΔCt值无明显变化(P>0.05).同样转染组Akt1和COX-2蛋白表达量与空载组和对照组比较分别下调70.5%和63.7%(P<0.01),空载组和对照组比较Akt1和COX-2蛋白表达差异无统计学意义(P>0.05).结论 靶向性Akt1和COX-2的shRNA腺病毒载体可以特异性抑制Akt1和COX-2的表达,可能成为胃癌靶向性Akt1和COX-2基因治疗的新策略.     

FasL逆转录病毒转移体系的建立及其在肝癌细胞中的表达

目的　研究Fas/FasL系统的生物学功能,探讨转FasL基因治疗肿瘤的可行性。方法将大鼠FasL全长cDNA亚克隆到逆转录病毒载体pLXSN中,获得FasL正向单拷贝插入子pLXSN/FasL