Objective To construct a recombinant live attenuated Salmonella typhimurium vaccine strain expressing Helicobacter pylori urease subunit B (ureB).Methods ureB gene was amplified by PCR and cloned into a prokaryotic expression plasmid pTrc99a, and the identified recombinant plasmid was then used to transform an attenuated Salmonella typhimurium vaccine strain SL3261. The ureB expressed in the recombinant vaccine strain was analyzed by SDS-PAGE and optical density scanning. Two and 10 days after recombinant strain intragastric immunization, the C57BL/6 mice were sacrificed, and the spleens and terminal ileums were cultured.Results The ureB gene could be amplified from the recombinant prokaryotic expression plasmid pTrc99A-ureB and the plasmids extracted from transformed SL3261 strain. SDS-PAGE and optical density scanning indicated that ureB was expressed in the recombinant vaccine strain SL3261 (pTrc99A-ureB) as a protein with 66*!kD of molecular weight. Recombinant strain was found in both spleen an terminal ileum of each mouse two and ten days after intragastric immunization.Conclusions A recombinant liver attenuated Salmonella typhimurium vaccine strain expressing Helicobacter pylori ureB was constructed and identified, and this study will help to develop an oral recombinant live vaccine against Helicobacter pylori infection.

人乳头瘤病毒6bL1双顺反子载体的构建及其在哺乳动物细胞内的表达

目的构建尖锐湿疣患者人乳头瘤病毒6b型晚期基因(HPV6b L1)的双顺反子表达载体,并使其在哺乳动物细胞内表达,以期建立含有HPV6b L1的细胞模型.方法表达质粒pEGFP-HPV6bL1经双酶切纯化后与经过相同双酶切的真核表达质粒pIRES2-EGFP连接,酶切鉴定,挑选阳性克隆进行测序.重组质粒pIRES2-HPV6bL1-EGFP转染进小鼠成纤维细胞(NIH3T3),荧光显微镜下观察EGFP蛋白的表达.RT-PCR检测HPV6b L1 mRNA的生成.结果成功构建含HPV6b L1的重组质粒pIRES2-HPV6bL1-EGFP.重组体成功转染进NIH3T3细胞,并用G418筛选.同时荧光倒置显微镜下可观察到细胞内有绿色荧光蛋白的表达.进一步进行RT-PCR,检测到HPV6b L1 mRNA的生成.结论成功构建携带HPV6b L1的重组体pIRES2-HPV6bL1-EGFP并转染入NIH3T3细胞.经荧光倒置显微镜观察及RT-PCR方法检测证明HPV6b L1在NIH3T3细胞内成功表达.

弓形虫SAG1 ROP1基因及其复合抗原基因的核酸免疫研究

1 前言刚地弓形虫是一种机会性致病原虫,寄生于宿主的细胞内,在机体免疫力下降的情况下,弓形虫大量增殖,可导致组织器官的损伤,引起弓形虫病.该病呈世界性分布,是严重危害人畜健康的寄生虫病之一.

AIM: PSP94 has been shown promise as a potential prostate cancer marker and it was reported that PSP94 can inhibit the growth of prostate cancer cell in vitro and in vivo. This study aimed to construct recombinant human PSP94 expression vector. METHODS:The PSP94 cDNA was obtained from normal prostate tissue, and recombinant plasmid pUC19-PSP94 was constructed. The target gene was identified and sequenced. Then the PSP94 gene was inserted to the secretory expression vector. RESULTS:The gene sequence of PSP94 was identified. The recombinant vector was constructed. The secreted PSP94 was isolated and identified by Western blot. CONCLUSION:The recombinated PSP94 could expressed PSP94 successfully.

This study investigated the protection against the ND in chickens by a recombinant DNA vaccine. A plasmid vector encoding NDV F protein, which is reqired for virus cell fusion and is important for vaccine induced immunity, was used as a model to study how DNA vaccines may be modulated by the simulaneous expression of chicken IL-2. The NDV D26 strain F gene with CMV promotor and BGH polyA signal sequence was amplified by PCR from eukaryotic plasmid pcDNA-F, which contains the full-length NDV F gene, and clond into reconstructed eukaryotic plasmid pcDNA-IL2, which contains chicken IL-2 gene. Restriction endonuclease cleavage and PCR amplification showed that a bicistronic plasmid encoding NDV F gene and chicken IL-2 separately was successfully constructed. Two-week-old SPF chickens were intramuscularly innoculated the recombinant plasmid. Antibody and lymphocyte proliferative assay showed that the humoral and cellular immunity of chickens vaccinated the recombinant plasmid greatly increased compared with those innoculated only plasmid expressing NDV F protein. Challenged with the lethal dose of NDV F48E9 strain, 72% chickens vaccinated recombinant plasmid were survived, and 30% chickens vaccinated plasmid expressing F protein were survived. These results proved the adjuvant effect of chicken IL-2, and further showed that the efficacy of a DNA vaccine can be greatly improved by simultaneous expression of IL-2.