Construction of an oral recombinant DNA vaccine from Hpylori neutrophil activating protein and its immunogenicity

• Published in: World journal of gastroenterology : WJG Vol. 12; no. 43; pp. 7042 - 7046
• Main Author: Bo Sun Zhao-Shen Li Zhen-Xing Tu Guo-Ming Xu Yi-Qi Du
• Format: Journal Article
• Language: English
• Published: 2006
• Subjects: 免疫球蛋白; 幽门螺杆菌; 细菌感染
• ISSN: 1007-9327; 2219-2840

AIM： To construct a live attenuated Salmonella typhimurium （S. typhimurium） strain harboring the H pylori neutrophil activating protein （HP-NAP） gene as an oral recombinant DNA vaccine, and to evaluate its immunogenicity. METHODS： By genetic engineering methods, the genomic DNA of Hpylori was extracted as a template. The total length of the HP-NAP gene was amplified by polymerase chain reaction （PCR） and cloned into pBT vector for sequencing and BLAST analysis, then subcloned into a eukaryotic expression vector pIRES followed by PCR identification and restriction enzyme digestion. The identified recombinant plasmid pIRES-NAP was transfected into COS-7 cells for target fusion protein expression, and its antigenicity was detected by Western blotting. Then the recombinant plasmid was transformed into a live attenuated S. typhimurium strain SL7207 as an oral vaccine strain, and its immunogenicity was evaluated with animal experiments. RESULTS： A 435 bp product was cloned using high homology with HP-NAP gene in GenBank （more than 98%）. With identification by PCR and restriction enzyme digestion, a recomoinant eukaryotic expression plasmid pIRES-NAP containing the HP-NAP gene of H pylori was successfully constructed. The expressed target protein had a specific reaction with Hpyloril whole cell antibody and showed a single strip result detected by Western blotting. Oral immunization of mice with recombinant DNA vaccine strain SL7207 （pIRES-NAP） also induced a specific immune response. CONCLUSION： The successful construction of HP-NAP oral DNA vaccine with good immunogenicity may help to further investigate its immunoprotection effects and develop vaccine against Hpylori infection.