人巨细胞病毒gB和pp150融合基因真核表达载体的构建及其免疫活性研究

目的 构建人巨细胞病毒（human cytomegalovirus,HCMV）糖蛋白（gB）和胞膜蛋白（pp150）的单基因及融合基因的真核表达载体并比较其免疫学活性,为研制HCMV核酸疫苗奠定实验基础.方法 PCR扩增HCMV gB及pp150并将其连接成融合基因,分别克隆至peDNA3.1（＋）真核表达载体;制备纳米粒DNA疫苗并免疫BALB/e小鼠,检测其体液免疫与细胞免疫应答.结果 成功制备了peDNA3.1（＋）-gB、peDNA3.1（＋）-pp150和peDNA3.1（＋）-gB-pp150纳米核酸疫苗;gB和gB-pp150核酸疫苗均能刺激小鼠产生较强的特异性抗体（P〈0.01）;pp150和gB-pp150核酸疫苗免疫组的小鼠脾细胞能产生较多的IFN-γ和较高的刺激指数.结论 HCMV gB单基因核酸疫苗能诱导较强的体液免疫应答,pp150单基因核酸疫苗则能诱导较强的细胞免疫应答;而gB-pp150的融合基因疫苗能诱导较强的体液免疫和细胞免疫应答.     

人巨细胞病毒gB和pp150融合基因真核表达载体的构建及其免疫活性研究

Objective To provide experimental evidence for development of human cytomegalovirus (HCMV) nucleic acid vaccine,HCMV surface protein(gB),membrane protein(pplSO),and gB-pp150 fused gene eukaryotie expression vector were constructed.Methods gB and pp150 genes were amplified and fused into gB-pp150,then were cloned into pcDNA 3.1(+) to obtain recombinant expression plasmids pcDNA 3.1(+)-gB,pcDNA 3.1(+)-pp150 and pcDNA 3.1(+)-gB-pp150,which were encapsulated with chitosan.Mouse were vaccinated and the humoral and eell immune response were determined by ELISA,specific proliferative response of plenie lymphocytes.Results The gB,pp150 and gB-pp150 fusion gene eukaryotie expression vector were successfully constructed.The antibodies A value induced by peDNA3.1(+)-gB or peDNA3.1(+)-gB-pp150 were much higher than that of peDNA3.1(+)(P<0.01).The IFN-γ levels induced by pcDNA3.1(+)-pp150 and peDNA3.1(+)-gB-pp150 were significantly higher than that of pcDNA3.1(+).There are significant diferenee between the stimulating indexes of pcDNA3.1(+)-pp150 or peDNA3.1(+)-gB-pp150 immunized and normal mice.Conclusion The DNA vaccine pcDNA3.1(+)-gB can induce significant humeral immunity response.and pcDNA3.1 (+)-pp150 can induce high cellular immune response,whereas pcDNA3.1(+)-gB-pp150 can induce both humeral and cellar immune responses in BALB/c mice.     

人巨细胞病毒pp65核酸疫苗的构建、表达与动物免疫效应

构建真核重组表达质粒PVAX1-pp65,通过对其表达产物的鉴定和免疫小鼠实验,探讨PVAX1-pp65载体对诱导免疫应答的效果及方式。用已构建的原核表达载体pp65-pet32a,经酶切后与DNA疫苗载体PVAX1连接,构建HCMVpp65核酸疫苗(PVAX1-pp65)。用脂质体法将其转染293细胞,经间接免疫荧光、免疫印迹试验来验证其表达的产物。同时,免疫小鼠后取其脾脏细胞,经流式细胞仪检测其CD4+和CD8+T细胞;并利用MTT法测定免疫小鼠的T细胞对ConA和重组pp65蛋白刺激后的增殖活性。结果显示构建的真核表达载体PVAX1-pp65,经测序验证其序列正确。体外转染实验结果表明转染重组质粒的细胞胞浆内呈现与特异性pp65单克隆抗体反应的颗粒状荧光产物,免疫印迹试验也显示重组质粒转染的细胞裂解物中有pp65蛋白条带。另外,免疫小鼠脾CD8+T细胞的含量明显高于对照组;免疫鼠脾细胞对重组pp65抗原蛋白的刺激后增殖反应明显。综上结果证实,成功地构建了HCMVpp65核酸疫苗,并能有效地表达,表达的蛋白具有良好的免疫原性和免疫反应性。HCMVpp65DNA疫苗可诱导小鼠产生针对HCMV的特异性细胞免疫应答,可作为一种有应用前景的核酸疫苗进一步深入研究。     

新生儿晚期黄疸人巨细胞病毒gB基因分型研究

目的了解引起新生儿晚期黄疸患者人巨细胞病毒（HCMV）gB基因型的分布,探讨HCMVgB基因多态性与黄疸之间的关系。结论采用荧光定量PCR法检测本院新生儿科98例晚期黄疸新生儿标本HCMV-DNA含量,巢式聚合酶链反应扩增阳性标本HCMVgB基因,并进行DNA测序,绘制种系进化树。利用HinfⅠ和RsaⅠ对gB基因进行限制性片段长度多态性（RFLP）分析。结果 30例晚期黄疸新生儿HCMV荧光定量PCR检测阳性,阳性率为30.6%。种系进化树分析结果显示gB基因分为4个基因型,gB1型15株（50%）,gB2型5株（16.7%）,gB3型9株（30.0%）,gB1/3混合型1株（3.3%）。以HCMV实验室标准株AD169作为参考,将序列进行同源性比较,gB1型同源性为94.7%～95.0%,gB2型同源性93.1%～93.4%,gB3型同源性94.7%,gB1/3型同源性93.7%。RFLP分析将gB基因分为4个基因型,分型结果与种系进化树分型一致。结论 HCMV感染是导致新生儿晚期黄疸的原因之一;gB基因的DNA序列比较保守,但仍存在一定的多态性,晚期黄疸新生儿中HCMV感染以gB1、gB3型为主。     

人PSCA基因真核载体的构建与表达

目的 克隆人PSCA(prosaae stem cell antigen)分子的cDNA,构建PSCA基因的真核表达载体,并在体外进行表达和鉴定.方法 从PSCA阳性细胞系LNCaP中提取总RNA,逆转录为cDNA.根据编码人PSCA的基因序列设计引物,以cDNA为模板,采用PCR技术扩增PSCA基因,将该基因插入到pcDNA3.1(+)真核载体,构建pcDNA3.1(+)-PSCA表达质粒.经限制性酶切鉴定和DNA序列测定结果证实后,将重组质粒pcDNA3.1(+)-PSCA转染Hela细胞,检测其体外瞬时表达.结果 测序证实得到人PSCA基因序列,序列分析显示没有发生无义突变.RT-PCR和免疫细胞化学分析结果分别表明转染细胞有目的 基因和分子的表达.结论成功克隆人PSCA基因,并在真核细胞中获得表达,为进一步构建基于PSCA的肿瘤疫苗奠定了基础.     

人巨细胞病毒UL150基因在临床低传代分离株中的多态性研究

目的 研究人巨细胞病毒(human cytomegalovirns,HCMV)UL150序列在临床低传代分离株中的多态性,探讨HCMV基因多态性与其感染引起不同临床症状之间的关系.方法 对29株经荧光定量PCR方法(Q-PCR)检测HCMV-DNA为阳性的临床低传代分离株进行HCMV UL150全序列PCR扩增,并对PCR扩增产物进行序列测定及分析.结果在29株临床低传代分离株中25株PCR扩增阳性.其中18株完成了测序.18株临床分离株HCMV UL150开放阅读框架(open reading frame,ORF)与HCMV Toledo株相应序列进行比较分析,显示18株低传代临床分离株的HCMV UL150 ORF均为1920bp,编码蛋白含有640个氨基酸,临床株的ORF及编码的氨基酸序列的长度均与Merlin株一致.结论 HCMV UL150基因在临床分离株中存在着高度的多态性,未发现其与HCMV感染不同临床症状间存在明显的关系.     

汉滩病毒M、S基因部分片段嵌合基因真核载体的构建与基因免疫

目的 在本室前期工作的基础上,进一步进行汉滩病毒M基因G2片段与S基因0．7Kb片段嵌合基因基因免疫的研究。方法 构建汉滩病毒76－118株M基因G2片段与S基因5‘端700bp片段的嵌合基因真核表达载体pcDNA3.1-G2S0.7。用该质粒免疫Balb/c小鼠,并用ELISA法及淋巴细胞增殖实验,检测基因免疫后的免疫应答效果。结果 限制性内切酶鉴定结果表明真核表达载体的构建正确。用pcDNA3.1-G2S0.7直接免疫小鼠。可诱导产生抗汉滩病毒核蛋白（NP）及糖蛋白（GP）特异性的抗体,抗体效价分别为1：200及1：80。淋巴细胞增殖实验表明,嵌合基因免疫小鼠脾细胞对NP及GP的增殖指数,均明显高于对照组。结论汉滩病毒M基因G2片段及S基因0．7kb片段的嵌合基因,既可刺激机体产生特异性的抗汉滩病毒体液免疫应答,也可刺激机体产生特异性的细胞免疫应答,本研究为进一步进行汉滩病毒基因疫苗的研究奠定了实验基础。     

HCMV pp65核酸疫苗表达载体的构建及其体内免疫效果评价

目的 构建人巨细胞病毒(HCMV)pp65基因表达载体并初步评价其作为核酸疫苗的体内免疫效果。方法利用分子克隆方法构建HCMVpp65表达载体pcDNA3．pp65；对其活性进行体外鉴定后，以肌肉和皮下2种途径、3种剂量组免疫小鼠；测量免疫小鼠的体重、体温等一般状况，利用M3T方法测定免疫小鼠的T细胞增殖活性、NK活性，利用ELISA方法测定小鼠的抗HCMV IgM、IgG抗体，免疫小鼠血清的病毒中和实验。结果成功构建：HCMVpp65表达载体pcDNA3．pp65并免疫小鼠后，小鼠体重、体温等一般状况未见明显变化，T细胞增殖活性增强，NK细胞活性增强，HCMVIgM、IgG抗体增高，且有时间、剂量依赖性，免疫小鼠血清对HCMV有部分中和作用。结论pcDNA3．pp65表达载体可引起机体特异性细胞免疫和体液免疫，可作为一种有一定应用前景的核酸疫苗进一步深入研究。     

gp350及gp350-C3d3融合基因真核载体的构建及其免疫功能研究

目的构建EB病毒包膜糖蛋白gp350全长序列及其与3个补体片段C3d串联基因在人体真核细胞中表达的载体,并进行其免疫功能的初步研究。方法将gp350基因序列分别与经BglⅡ和BamHⅠ双酶切的真核表达载体pSG.SS.YL和pSG.SS.C3d3.YL连接,转化后挑取阳性克隆进行PCR、酶切鉴定并测序;将重组载体利用脂质体法分别转染人类Hela细胞培养16~24 h后,用Western blot及细胞免疫组化染色检测gp350蛋白和gp350-C3d3融合蛋白的表达。结果成功构建含gp350全长基因序列的载体pSG.SS.gp350.YL和pSG.SS.gp350.C3d3.YL,并能够转染人类Hela细胞;经细胞免疫组织化学染色及Westernblot蛋白检测转染组均能常规水平表达,对照组则无该蛋白表达,但两转染组的表达量无明显差异。结论构建成功含有gp350的2个真核表达质粒并能够在人体细胞中表达相应蛋白,为下一步进行检测功能性试验奠定基础。     

人巨细胞病毒反义寡核苷酸抗病毒活性研究

目的观察反义寡核苷酸（ＡＳＯＮ）的抗病毒活性。方法根据ＨＣＭＶ立即早期基因ＵＬ３６序列，设计并合成了３条与该基因互补的硫代反义寡核苷酸，以人胚肺细胞作为病毒感染的靶细胞做了体外抗病毒活性评价。结果研究结果显示作用于剪接供体的ＡＳＯＮ具有较强的抗病毒活性。结论特异的ＡＳＯＮ有一定的抗病毒活性，有可能作为一种新的手段用于人ＨＣＭＶ感染的防治     

Enhanced immunogenicity of DNA fusion vaccine encoding secreted hepatitis B surface antigen and chemokine RANTES

To increase the potency of DNA vaccines, we constructed genetic fusion vaccines encoding antigen, secretion signal, and/or chemokine RANTES. The DNA vaccines encoding secreted hepatitis B surface antigen (HBsAg) were constructed by inserting HBsAg gene into an expression vector with an endoplasmic reticulum (ER)-targeting secretory signal sequence. The plasmid encoding secretory HBsAg (pER/HBs) was fused to cDNA of RANTES, generating pER/HBs/R. For comparison, HBsAg genes were cloned into pVAX1 vector with no signal sequence (pHBs), and further linked to the N-terminus of RANTES (pHBs/R). Immunofluorescence study showed the cytoplasmic localization of HBsAg protein expressed from pHBs and pHBs/R, but not from pER/HBs and pER/HBs/R at 48 h after transfection. In mice, RANTES-fused DNA vaccines more effectively elicited the levels of HBsAg-specific IgG antibodies than pHBs. All the DNA vaccines induced higher levels of IgG(2a) rather than IgG(1) antibodies. Of RANTES-fused vaccines, pER/HBs/R encoding the secreted fusion protein revealed much higher humoral and CD8(+) T cell-stimulating responses compared to pHBs/R. These results suggest that the immunogenicity of DNA vaccines could be enhanced by genetic fusion to a secretory signal peptide sequence and RANTES.     

HCV核心-包膜E2抗原融合基因DNA疫苗的构建及对小鼠的免疫应答试验

目的：观察一种结构新颖的HCV融合抗原DNA疫苗在BALB/c小鼠的免疫效果，探讨其用于防治丙型肝炎的可行性。方法：用重叠延伸PCR拼接编码小鼠IgG kappa链信号肽和通用型辅助性T细胞表位PADRE的DNA片段，PCR分别扩增HCV核心抗原基因和包膜E2抗原基因，将3段基因插入真核表达载体pcDNA3.1，构成重组表达质粒pST-CE2t，转染COS7细胞，免疫组化检测HCV抗原的表达。将pST-CE2t和HCV核心抗DNA疫苗pcDNA3.1core分别肌肉注射接种BALB/c小鼠，检测小鼠的血清抗体、T细胞增殖和CTL反应。结果：pST-CE2t可在COS7细胞内表达HCV核心抗原和E2抗原，接种于BALB/c小鼠能有效诱导体液和细胞免疫应答，其中抗HCV核心抗原免疫应答的强度明显超过pcDNA3.1core，且更趋向于TH1型免疫应答。结论：pST-CE2t对于丙型肝炎的防治有潜在的应用价值。     

优化密码促进HPV 6b E7蛋白表达及DNA疫苗诱导的细胞免疫反应

目的：探讨优化密码对人乳头瘤病毒6b型（HPV 6b）基因表达及免疫原性的影响，为治疗性DNA疫苗的研究奠定基础。方法：设计合成含优化密码及pRB结合位点突变的HPV 6bE7(humE7）全长基因。测序验证无误后，定向克隆于pcDNA3的Kpn I和EcoR I位点，成功构建真核表达质粒pcDNA3-hu-mE7。体外转染COS－1细胞，免疫荧光检测其E7蛋白表达。C57BL／6小鼠胫前肌内接种裸DNA，观察其诱导的细胞免疫反应。结果：pcDNA3-hu-mE7在COS－1细胞获得明显表达，表达产物主要位于细胞核中。DNA免疫结果显示，与含有野生型E7基因的表达质粒pcDNA3-wtE7比较，pcDNA3-hu-mE7免疫小鼠脾细胞培养上清中IFN-γ产生明显升高，CD8^ 和CD4^ 淋巴细胞活性增强。结论：优化密码能促进HPV 6b E7蛋白表达及DNA疫苗诱导的细胞免疫反应。     

人乳头瘤病毒11型L1/E7嵌合DNA疫苗的构建及其诱导的免疫效应

Objective To construct chimerical DNA vaccine plasmid of human papiUomavirus type 11 (HPV11) L1-E7, and to evaluate its immunogenicity. Methods Molecular cloning techniques were used to construct recombinant plasmid PeDNA3 L1-E7 as a DNA vaccine. BALB/c mice were vaccinated with DNA recombinants through muscle injection. IL-2 and γ-INF secreted by immunized spleens lymphocyte and HPV 11 LI or E7 specific antibodies were assayed by ELISA method. Spleens lymphocyte proliferation was measured by MTT assay. Results The chimerical DNA plasmid of pcDNA3 LI-E7 was constructed correctly. Specific anti-HPV11 E7 and L1 antibodies, specific lymphocyte proliferation and secretions of IL-2 and γ-INF were detected in vaccinated mice. Conclusion Specific immune response, including cellular immunity and humoral immunity, could been detected in mice vaccinated with chimerical DNA vaccine of pcDNA3 L1-E7.     

人乳头瘤病毒11型L1/E7嵌合DNA疫苗的构建及其诱导的免疫效应

Objective To construct chimerical DNA vaccine plasmid of human papiUomavirus type 11 (HPV11) L1-E7, and to evaluate its immunogenicity. Methods Molecular cloning techniques were used to construct recombinant plasmid PeDNA3 L1-E7 as a DNA vaccine. BALB/c mice were vaccinated with DNA recombinants through muscle injection. IL-2 and γ-INF secreted by immunized spleens lymphocyte and HPV 11 LI or E7 specific antibodies were assayed by ELISA method. Spleens lymphocyte proliferation was measured by MTT assay. Results The chimerical DNA plasmid of pcDNA3 LI-E7 was constructed correctly. Specific anti-HPV11 E7 and L1 antibodies, specific lymphocyte proliferation and secretions of IL-2 and γ-INF were detected in vaccinated mice. Conclusion Specific immune response, including cellular immunity and humoral immunity, could been detected in mice vaccinated with chimerical DNA vaccine of pcDNA3 L1-E7.     

人乳头瘤病毒11型L1/E7嵌合DNA疫苗的构建及其诱导的免疫效应

Objective To construct chimerical DNA vaccine plasmid of human papiUomavirus type 11 (HPV11) L1-E7, and to evaluate its immunogenicity. Methods Molecular cloning techniques were used to construct recombinant plasmid PeDNA3 L1-E7 as a DNA vaccine. BALB/c mice were vaccinated with DNA recombinants through muscle injection. IL-2 and γ-INF secreted by immunized spleens lymphocyte and HPV 11 LI or E7 specific antibodies were assayed by ELISA method. Spleens lymphocyte proliferation was measured by MTT assay. Results The chimerical DNA plasmid of pcDNA3 LI-E7 was constructed correctly. Specific anti-HPV11 E7 and L1 antibodies, specific lymphocyte proliferation and secretions of IL-2 and γ-INF were detected in vaccinated mice. Conclusion Specific immune response, including cellular immunity and humoral immunity, could been detected in mice vaccinated with chimerical DNA vaccine of pcDNA3 L1-E7.     

人乳头瘤病毒11型L1/E7嵌合DNA疫苗的构建及其诱导的免疫效应

Objective To construct chimerical DNA vaccine plasmid of human papiUomavirus type 11 (HPV11) L1-E7, and to evaluate its immunogenicity. Methods Molecular cloning techniques were used to construct recombinant plasmid PeDNA3 L1-E7 as a DNA vaccine. BALB/c mice were vaccinated with DNA recombinants through muscle injection. IL-2 and γ-INF secreted by immunized spleens lymphocyte and HPV 11 LI or E7 specific antibodies were assayed by ELISA method. Spleens lymphocyte proliferation was measured by MTT assay. Results The chimerical DNA plasmid of pcDNA3 LI-E7 was constructed correctly. Specific anti-HPV11 E7 and L1 antibodies, specific lymphocyte proliferation and secretions of IL-2 and γ-INF were detected in vaccinated mice. Conclusion Specific immune response, including cellular immunity and humoral immunity, could been detected in mice vaccinated with chimerical DNA vaccine of pcDNA3 L1-E7.