重组核酸疫苗诱导小鼠抗血吸虫感染的免疫学研究

目的为日本血吸虫病的防治寻求新的高效联合基因免疫策略。方法构建共表达日本血吸虫相对分子质量23000表膜蛋白(Sj23)基因与鼠IL12基因的核酸疫苗质粒pVIVO2IL12Sj23,转染HEK293细胞,通过RTPCR,Westernblot及ELISA法检测Sj23和IL12蛋白的表达。接种并攻击感染BALB/c小鼠,以减虫率和减卵率评价其免疫保护力,同时设攻击感染对照组、空白质粒pVIVO2组、pVIVO2IL12组和pVIVO2Sj23组。用ELISA法和WesternBlot分析免疫小鼠血清中抗体。以脾细胞培养法检测经SEA刺激后,小鼠脾细胞分泌IFNγ和IL4的水平。并以FCM分析脾细胞亚群。结果经瞬时转染HEK293细胞证明质粒pVIVO2IL12Sj23能在体外进行表达。免疫小鼠后获得了4553%的减虫率和5835%的减卵率,较单价DNA疫苗pVIVO2Sj23免疫效果好(P<005)。ELISA法和WesternBlot检测抗体结果表明免疫小鼠产生了抗Sj23特异性IgG抗体。pVIVO2IL12Sj23免疫组IFNγ的水平较对照组显著升高而IL4水平较对照组低。攻击感染后各实验组小鼠脾细胞的CD4+,CD8+亚群比率无显著差别(P>005)。结论pVIVO2IL12Sj23DNA疫苗具有诱导BALB/c小鼠产生较好的抗血吸虫感染免疫保护效果。细胞因子IL12作为基因佐剂,具有诱导Th1型免疫反应从而增强DNA疫苗免疫保护性的作用。     

日本血吸虫多价DNA疫苗pBK-Sj26(Sj32)-Sj23免疫效果的观察

为了观察血吸虫病多价DNA疫苗的保护力,将小鼠分成5组空白对照组、空质粒对照组、单价抗原DNA疫苗pBK-CMV-Sj23组、多价抗原DNA疫苗pBK-CMV-Sj26-Sj23和pBK-CMV-Sj32-Sj23组.大量提取各组质粒DNA后,各组于0、3、5周在BALB/c小鼠股四头肌注射相应质粒DNA,9周用血吸虫尾蚴攻击感染,15周剖杀小鼠计算减虫率及减卵率.结果显示与对照组比较,实验组小鼠减虫率及减卵率有极显著性差异(P<0.01);与单价pBK-CMV-Sj23组比较,多价DNA疫苗组的减虫率及减卵率有显著性差异.提示血吸虫多价DNA疫苗诱导小鼠对血吸虫的保护力优于单价DNA疫苗.     

日本血吸虫抗原的表位模拟肽筛选及免疫保护性

目的　筛选日本血吸虫雄虫抗原的表位模拟肽 ,并探讨其诱导小鼠抗日本血吸虫的免疫保护性。　方法　用日本血吸虫可溶性雄虫抗原的IgG对噬菌体随机 1 2肽库进行亲和筛选。 3轮筛选后 ,经Dot-ELISA检测获得阳性噬菌体克隆 ,并用混合特异性噬菌体克隆免疫小鼠及进行抗日本血吸虫免疫保护性分析。　结果　 1 8个特异性噬菌体克隆均显示有抗原性 ,其噬菌体混合克隆免疫诱导小鼠产生了特异性抗体 ,以及 31 72 %的减虫率和 51 54%的减卵率 ,与对照组比较差异有显著性 (P <0 0 0 1 )。　结论　筛选噬菌体肽库获得的日本血吸虫可溶性雄虫抗原的表位模拟肽分子能诱导小鼠产生抗日本血吸虫的保护性免疫。     

日本血吸虫DNA疫苗的构建及其保护性免疫的研究

为探讨血吸虫ＤＮＡ疫苗保护性免疫效果,首先构建、鉴定和表达日本血吸虫ＤＮＡ疫苗（ｐＣＤ－Ｓｊ３２）。实验结果表明：ｐＣＤ－Ｓｊ３２免疫ＢＡＬＢ／Ｃ小鼠能诱导产生抗日本血吸虫感染免疫力,减虫率为３５．６％～４４．４％,减卵率为３９．４％～６９．０％;１００μｇＤＮＡ一次肌肉注射,免疫后８周攻击感染组的效果好;ＣＤ８＋Ｔ淋巴细胞、ＩＬ－２、ＴＮＦ和ＩＮＦ－γ可能在血吸虫病免疫功能调控中起重要作用;ｐＣＤ－Ｓｊ３２能诱导宿主产生高滴度特异性抗体,并在体外能介导巨噬细胞产生抗体依赖细胞介导的细胞毒性（ＡＤＣＣ）免疫效应。结果提示,ｐＣＤ－Ｓｊ３２有可能发展为新的预防血吸虫病的亚单位疫苗。     

核酸疫苗Sj31BIN联合IL-12免疫抗日本血吸虫攻击感染的实验研究

目的：在证明日本血吸虫重组蛋白酶B核酸疫苗Sj31BIN具有抗生殖免疫作用的基础上,联合使用IL-12,观察IL-12是否具有佐剂效果。方法：分别用Sj31BIN IL-12和IL-12免疫Balb／C小鼠。攻击感染后6周计数成虫负荷和组织内虫卵数及肝脏表面虫卵结节数。结果：Sj31BIN IL-12免疫小鼠可降低成虫发育率。肝组织减卵率为59．74％;肠组织减卵率为59．60％;肝脏表面虫卵结节减少率为71．30％;单独使用IL-12有一定的免疫保护作用。结果：Sj31BIN IL-12能诱导小鼠产生较强的抗生殖免疫作用。     

DNA vaccine pCD-Sj32 and its efficacy of protective immunity against infection of Schistosoma japonicum

Ｓｃｈｉｓｔｏｓｏｍｉａｓｉｓｉｓａｇｒｏｕｐｏｆｓｅｖｅｒｅｐａｒａｓｉｔｉｃｄｉｓｅａｓｅｓｉｎｈｕｍａｎｂｅｉｎｇｓａｎｄｄｏｍｅｓｔｉｃａｎｉｍａｌｓ．ＡｃｃｏｒｄｉｎｇｔｏＷＨＯｄａｔａ（１９９０）,ｗｉｔｈａｐｒｅｖａｌｅｎｃｅｏｆ２００ｍｉｌｌｉｏｎｐｅｏｐｌｅｉｎｆｅｃｔｅｄａｎｄｓｏｍｅ２００ｔｈｏｕｓａｎｄｓｄｅａｔｈｓｐｅｒｙｅａｒ．ＳｃｈｉｓｔｏｓｏｍｉａｓｉｓｒｅｍａｉｎｓａｍａｊｏｒｈｅａｌｔｈｐｒｏｂｌｅｍｉｎｔｈｅｄｅｖｅｌｏｐｉｎｇｗｏｒｌｄｉｎｃｌｕｄｉｎｇＣ…     

Construction and Expression of DNA Vaccine pIRES-Sj97-Sj14-Sj26 and Its Immunogenicity in Mice

To find a new preventive strategy for the infection of Schistosoma japonica, plasmid pIRES-Sj97-Sj 14-Sj26 that contains fatty binding protein （Sj 14）, GST （Sj26） and paramyocin （Sj97） that are expressed on the membrane, was constructed. RT-PCR was used to detect the expression of Sj 14 mRNA, Sj26 mRNA and Sj97 mRNA in the Hela cells, the indirect immunofluorescent test was employed for the detection of the expression of trans-membrane Sj26 after the plasmid was transfected into Hela cells. Fifty BALB/c mice were randomly divided into 5 groups and plRES-Sj97-SjI4-Sj26 plasmid DNA, plRES-Sj 14-Sj26 plasmid DNA, plRES-Sj26 plasmid DNA, plRES blank vector and normal saline were respectively injected into the quadriceps muscles of thigh Eight weeks after the immunization the mice were killed and significantly higher level of IgG was detected in the plRES-Sj97-Sj 14-Sj26 group as compared with the plRES blank vector, normal saline and plRES-Sj26 groups （P〈 0.01） and the plRES-Sj 14-Sj26（P〈0.05）. Single splenocyte suspension was prepared to detected the level of IFN-T by ELISA and the lymphocyte stimulating index （SI） by MTT. SI was significantly higher of in the plRES-Sj97-Sj 14-Sj26 group than in other groups （P〈 0.01）, while the IFN-T level was significantly higher the plRES-Sj97-Sj 14-Sj26 group than in plRES blank vector and normal saline groups （P〈0.01）, but no significant differences were found when compared with plRES-Sj 14-Sj26 and plRES-Sj26 groups. Flow cytometery showed that the percentages of CD4＋ and CD8＋ T cells were much higher in the plRES-Sj97-Sj 14-Sj26 group （P〈 0.01, P〈0.05）. It was concluded that plRES-Sj97-Sj 14-Sj26 vaccine may induce stronger immune response in BALB/c mice.     

日本血吸虫Rho GTPaseDNA及重组蛋白免疫保护效果研究

目的研究日本血吸虫中国大陆株Rho家族小分子G蛋白(Sj-Rho GTPase)DNA疫苗及重组蛋白疫苗免疫保护效果.方法将pcDNA3.1-SjRho GTPase DNA疫苗和pGEX-5X-3原核载体所表达的重组蛋白疫苗三次分别或联合免疫昆明鼠,3周后,每鼠感染40条尾蚴,42 d后剖杀小鼠,记数成虫和肝脏虫卵数. 结果与佐剂或空白质粒对照组相比,DNA疫苗、重组蛋白疫苗及联合免疫分别获得22.16%(P<0.01)、18.71%(P<0.05)和39.20%(P<0.001)的减虫率以及34.55%、20.07%和49.55%(P<0.001)的肝组织减卵率.结论 Sj-Rho GTPase DNA疫苗及重组蛋白疫苗均可诱导小鼠产生一定的免疫保护作用,且联合免疫方案保护效果好于单一疫苗.     

日本血吸虫复合DNA疫苗的组织表达及免疫保护效果研究

目的 :观察本课题组所构建日本血吸虫大陆株复合DNA疫苗VR10 12 SjGST和VR10 12 SjGST Sj32在小鼠肌肉组织中的表达 ,并进行免疫保护效果测定。方法 :用纯化质粒免疫昆明鼠 :4 8只小鼠分为 4组 ,两个对照组的小鼠分别于股四头肌注射生理盐水 10 0 μl或空质粒VR10 12 10 0 μg,两个实验组的小鼠则同法分别注射VR10 12 SjGST和VR10 12 SjGST Sj32各 10 0 μg。末次免疫后 ,每组解剖两只小鼠 ,以间接免疫荧光法观察SjGST、Sj32在肌肉组织中的表达。其余每只鼠经腹部感染 10条尾蚴 ,4 5d后剖杀计数各小鼠成虫数和肝卵数。结果 :小鼠肌肉组织表达出抗原特异性蛋白质抗原分子。与生理盐水组比较 ,两个实验组的减虫率分别为 33.9%和及 2 7.14 %(均为P <0 .0 5 ) ,减卵率分别为 6 1.86 %和 6 8.87% (均为P <0 .0 0 1)。与VR10 12 SjGST组相比 ,VR10 12 SjGST Sj32组的减卵率为 18.5 1% (P <0 .0 5 )。结论 :DNA疫苗VR10 12 SjGST和VR10 12 SjGST Sj32能在组织中正常表达 ,能诱导小鼠产生一定水平的抗日本血吸虫感染保护作用 ,复合疫苗的保护效果要大于单价疫苗     

日本血吸虫重组BCG-Sj26GST疫苗诱导小鼠脾细胞IL-6变化的研究

目的：研究日本血吸虫重组BCG－Si26GST疫苗对小鼠脾细胞IL－6的影响,方法：实验1采用该疫苗皮下免疫小鼠,免疫后8周用日本血吸虫尾缦进行攻击感染,感染后6周剖杀小鼠,同时设有PBS对照组,实验2用该疫苗皮下和静脉注射分免疫小鼠,于免疫后,0,4,8,10,14和16周各剖杀4只,分离脾脏,用Si26或PHA刺激脾细胞,用ELISA法检测5 清液中IL－6含量,结果：疫苗免疫尾缦攻击后,IL－6水平无明显变化;动态观察发现IL－6于疫苗免疫后8－10周达最高水平,结论：IL－6可能与日本血吸虫重组BCG－Si26GST疫苗诱导的保护性免疫力无关。     

Sj Dad1反义核酸抗日本血吸虫感染的实验研究

目的 进一步鉴定已获得的日本血吸虫新基因 Ｓｊ Ｄａｄ１的功能。方法 构建Ｓｊ Ｄａｄ１反义（ａｎｔｉｓｅｎｓｅ）核酸载体ＰＥＧＦＰ－Ｎ３－Ｓｊ Ｄａｄ１和正义（ｓｅｎｓｅ）核酸载体 ｐＥＧＦＰ－Ｎ３－Ｓｊ Ｄｅｄ１．ＢＡＬＢ／ｃ小鼠感染日本血吸虫尾蚴后第 ３天,通过小鼠尾静脉分别注射ＰＥＧＦＰ－Ｎ３－Ｓｊ Ｄａｄ１（ａｎｔｉｓｅｎｓｅ）、ｐＥＧＦＰ－Ｎ３－Ｓｊ Ｄａｄｌ（ｓｅｎｓｅ）、空载体和生理盐水。４５ｄ后解剖实验小鼠进行保护性效果评价。结果 在ＰＥＧＦＰ－Ｎ３－Ｓｊ　Ｄａｄ１（ａｎｔｉｓｅｎｓｅ）组、ｐＥＧＦＰ－Ｎ３－Ｓｊ　Ｄａｄｌ（ｓｅｎｓｅ）组以及ｐＥＧＦＰ－Ｎ３组小鼠肺部冰冻切片检查发现在童虫周围有绿色荧光出现,而在生理盐水组则无此现象。但各实验组保护性效果无统计学差异（Ｐ＞ ０．０５）。结论Ｓｊ Ｄａｄ１反义核酸无明显的抗日本血吸虫感染的效果,尚需寻找其它方法对 Ｓｊ Ｄａｄ１的疫苗候选基因价值作进一步的鉴定。     

日本血吸虫（大陆株）融合蛋白保护性免疫力的研究

采用日本血吸虫(大陆株)融合蛋白加福氏佐剂免疫小鼠,攻击感染后,不但可减少虫负荷(减虫率为29.2—51.0%),还可降低血吸虫雌虫的产卵量(减卵率为52.1—74.3%),血清抗体在初次免疫后3周即明显升高,并持续维持较高的水平。结果表明,经大肠杆菌表达的日本血吸虫重组融合蛋白能诱导抗攻击感染的保护性免疫力,可望作为混合多价疫苗的候选组份而大规模的生产。     

核酸疫苗Sj31BIN联合IL-12免疫抗日本血吸虫攻击感染的实验研究

目的 :在证明日本血吸虫重组蛋白酶B核酸疫苗Sj31BIN具有抗生殖免疫作用的基础上 ,联合使用IL 12 ,观察IL 12是否具有佐剂效果。方法 :分别用Sj31BIN +IL 12和IL 12免疫Balb/C小鼠。攻击感染后 6周计数成虫负荷和组织内虫卵数及肝脏表面虫卵结节数。结果 :Sj31BIN +IL 12免疫小鼠可降低成虫发育率。肝组织减卵率为5 9 74% ;肠组织减卵率为 5 9 6 0 % ;肝脏表面虫卵结节减少率为 71 30 % ;单独使用IL 12有一定的免疫保护作用。结论 :Sj31BIN +IL 12能诱导小鼠产生较强的抗生殖免疫作用。     

重组日本血吸虫SjGST-Sj32蛋白诱导小鼠保护性免疫的研究

应用基因工程技术分别表达出ＳｊＧＳＴＳｊ３２,Ｓｊ３２和ＳｊＧＳＴ,用于保护性免疫的动物实验及其体液免疫机制的初步探讨。结果：与对照组相比,重组ＳｊＧＳＴＳｊ３２组,Ｓｊ３２组,Ｓｊ３２＋ＳｊＧＳＴ组均有明显的减虫效果（Ｐ＜０．０５）。上述三组及ＳｊＧＳＴ组的肝脏虫卵计数均较对照组为少（Ｐ＜０．０１）。提示重组Ｓｊ３２ｋＤ蛋白可诱导小鼠产生明显的抗日本血吸虫攻击感染的保护性免疫及抗生殖免疫效果,而ＳｊＧＳＴ仅表现出一定的抗生殖免疫效果。     

重组日本血吸虫SjGT—Sj32蛋白诱导小鼠保护免疫的研究

应用基因工程技术分别表达出ＳｊＧＳＴ－Ｓｊ３２,Ｓｊ３２和ＳｊＧＳＴ,用于保护性免疫的动物实验及其体液免疫机制的初步探讨。结果：与对照组相比,重组ＳｊＧＳＴ－Ｓｊ３２组,Ｓｊ３２组,Ｓｊ３２＋ＳｊＧＳＴ组均有明显的减虫效果。上述三组及ＳｊＧＳＴ组的肝脏虫卵计数的均较对照组为少。提示重组Ｓｊ３２ｋＤ蛋白可诱导小鼠产生明显的抗日本血吸虫攻击感染的保护性免疫及抗生殖免疫效果,而ＳｊＧＳＴ仅表现出一定的抗     

Nanoparticles as a vaccine adjuvant of anti-idiotypic antibody against schistosomiasis

Background The development of new adjuvants for human use has been the focus of attention. This study’s aim is to explore the possibility of using nanoparticle Ca nanoparticles (CA) as a vaccine adjuvant of anti-idiotypic antibody NP30 against schistosomiasis and its protective mechanisms. Methods Nanoparticle CA-NP30 conjugate (CA-NP30) was fabricated. BALB/c mice were immunized actively with CA-NP30 to evaluate its effects of protective immunity on mice. The serum levels of specific IgG, IgG1 and IgG2a antibodies against NP30 and the concentrations of IFN-γ and IL-4 in supernatant of splenocytes were determined via ELISA. Results Nanoparticle CA could enhance significantly the protective immunity of NP30 against infection of Schistosoma japonicum and the worm reduction rose from 36.0% (NP30 alone) to 52.6%. The serum levels of specific IgG, IgG1 and IgG2a antibodies against NP30 increased remarkably, as compared with those of the group immunized with NP30 alone. The concentration of IFN-γ in supernatant of splenocyte was drastically elevated ［the groups immunized with CA-NP30 and NP30 alone were (493.80±400.74) pg/ml and (39.03±39.58) pg/ml, respectively］, but the concentration of IL-4 showed no significant difference from that of NP30 alone ［(27.94±9.84） pg/ml vs （27.28±14.44） pg/ml］. Conclusions Nanoparticle CA could act as a vaccine adjuvant of anti-idiotypic antibody NP30 against schistosomiasis. The mechanism could be that CA-NP30 enhances humoral and cellular immune responses in mice.     

Construction and Expression of Bivalent Membrane-anchored DNA Vaccine Encoding Sj14FABP and Sj26GST Genes

In order to construct a eukaryotic co-expression plasmid containing membrane-anchored Sjc14FABP and Sjc26GST genes and identify their expression in vitro, Sj 14 and Sj26 genes were obtained by RT-PCR with total RNA of Schistosoma japonicum adult worms as the template and cloned into eukaryotic expression plasmid pVAC to construct recombinant plasmids pVAC-Sj14 and pVAC-Sj26. Then a 23 amino-acid signal peptide of human interleukin-2 (IL-2) upstream Sj14 or Sj26 gene and a membrane-anchored sequence containing 32 amino-acids of carboxyl-terminal of human plaeental alkaline phosphatase (PLAP) downstream were amplified by PCR as the template of plasmid pVAC-Sj14 or pVAC-Sj26 only to get two gene fragments including Sj14 gene and Sj26 gene. The two modified genes were altogether cloned into a eukaryotic co-expression plasmid pIRES, resulting in another new recombinant plasmid pIRES-Sj26-Sj 14. The expression of Sl14 and Sl26 genes was detected by RT-PCR and indirect immunofluorescent assays (IFA) when the plasmid pIRES-Sj26-Sj14 was transfected into eukaryotic Hela cells. Restriction enzyme analysis, PCR and sequencing results revealed that the recombinant plasmids pVAC-Sj14, pVAC-Sj26 and pIRES-Sj26-Sj 14 were successfully constructed and the expression of modified Sj 14 and Sj26 genes could be detected by RT-PCR and IFA. A bivalent membrane-anchored DNA vaccine encoding Sj14 and Sj26 genes was acquired and expressed proteins were proved to be mostly anchored in cellular membranes.     

日本血吸虫重组BCG-Sj26GST疫苗免疫小鼠血清IgG动态观察及免疫保护力的研究

为检测血吸虫重组BCG-Sj26GST疫苗免疫小鼠血清IgG动态变化和免疫保护力,采用106CFU疫苗皮下1次和3次接种小鼠,接种后8周用日本血吸虫尾蚴攻击感染。感染后6周剖杀小鼠,计算减虫率和减卵率,同时设有BCG对照组。结果发现实验组免疫后血清IgG抗体迅速升高并持续于高水平;减虫率分别为39.74%和39.74%,减卵率分别为62.86%和55.62%,与对照组相比均有非常显著的差异（P<0.01）。而免疫3次和免疫1次小鼠血清IgG抗体水平及减虫率、减卵率均无显著差异。血吸虫重组BCG-Sj26GST疫苗皮下注射1次即能诱导小鼠较高水平的IgG抗体和免疫保护力,是一种比较理想的新型疫苗,值得进一步研究。     

Construction and expression of DNA vaccine pIRES-Sj97-Sj14-Sj26 and its immunogenicity in mice

Summary To find a new preventive strategy for the infection of Schistosoma japonica, plasmid pIRES-Sj97-Sj14-Sj26 that contains fatty binding protein (Sj14), GST (Sj26) and paramyocin (Sj97) that are expressed on the membrane, was constructed. RT-PCR was used to detect the expression of Sj14 mRNA, Sj26 mRNA and Sj97 mRNA in the Hela cells, the indirect immunofluorescent test was employed for the detection of the expression of trans-membrane Sj26 after the plasmid was transfected into Hela cells. Fifty BALB/c mice were randomly divided into 5 groups and pIRES-Sj97-Sj14-Sj26 plasmid DNA, pIRES-Sj14-Sj26 plasmid DNA, pIRES-Sj26 plasmid DNA, pIRES blank vector and normal saline were respectively injected into the quadriceps muscles of thigh. Eight weeks after the immunization the mice were killed and significantly higher level of IgG was detected in the pIRES-Sj97-Sj14-Sj26 group as compared with the pIRES blank vector, normal saline and pIRES-Sj26 groups (P<0.01) and the pIRES-Sj14-Sj26(P<0.05). Single splenocyte suspension was prepared to detected the level of IFN-γ by ELISA and the lymphocyte stimulating index (SI) by MTT. SI was significantly higher of in the pIRES-Sj97-Sj14-Sj26 group than in other groups (P<0.01), while the IFN-γ level was significantly higher the pIRES-Sj97-Sj14-Sj26 group than in pIRES blank vector and normal saline groups (P<0.01), but no significant differences were found when compared with pIRES-Sj14-Sj26 and pIRES-Sj26 groups. Flow cytometery showed that the percent-ages of CD4+ and CD8+ T cells were much higher in the pIRES-Sj97-Sj14-Sj26 group (P< 0.01, P<0.05). It was concluded that pIRES-Sj97-Sj14-Sj26 vaccine may induce stronger immune response in BALB/c mice. This project was supported by grants from National Natural Sciences Foundation of China (No. 30471603).     

Construction and Expression of Bivalent Membrane-anchored DNA Vaccine Encoding Sj14FABP and Sj26GST Gene

In order to construct a eukaryotic co-expression plasmid containing membrane-anchored Sjc14FABP and Sjc26GST genes and identify their expression in vitro, Sj 14 and Sj26 genes were ob- tained by RT-PCR with total RNA of Schistosoma japonicum adult worms as the template and cloned into eukaryotic expression plasmid pVAC to construct recombinant plasmids pVAC-Sjl4 and pVAC-Sj26. Then a 23 amino-acid signal peptide of human interleukin-2 （IL-2） upstream Sj 14 or Sj26 gene and a membrane-anchored sequence containing 32 amino-acids of carboxyi-terminal of human placental alkaline phosphatase （PLAP） downstream were amplified by PCR as the template of plasmid pVAC-Sj14 or pVAC-Sj26 only to get two gene fragments including Sj14 gene and Sj26 gene. The two modified genes were altogether cloned into a eukaryotic co-expression plasmid plRES, resulting in another new recombinant plasmid plRES-Sj26-Sj14. The expression of Sj 14 and Sj26 genes was detected by RT-PCR and indirect immunofluorescent assays （IFA） when the plasmid plRES-Sj26-Sj 14 was transfected into eukaryotic Hela cells. Restriction enzyme analysis, PCR and sequencing results revealed that the recombinant plasmids pVAC-Sj14, pVAC-Sj26 and plRES-Sj26-Sj 14 were successfully constructed and the expression of modified Sj 14 and Sj26 genes could be detected by RT-PCR and IFA. A bivalent membrane-anchored DNA vaccine encoding Sj 14 and Sj26 genes was acquired and expressed proteins were proved to be mostly anchored in cellular membranes.