恶性疟原虫裂殖子表面蛋白2融合HBS基因重组质粒的免疫原性研究

目的　构建恶性疟原虫海南分离株 (FCC1/HN)裂殖子表面蛋白 2 (MSP2 )融合HBsAg基因片断真核重组表达质粒 pVXORF1-PfMSP2 -HBS ,观察该DNA疫苗的免疫特性。方法　 (1)以恶性疟原虫海南分离株 (FCC1/HN)基因组为模板 ,扩增出pfMSP2 DNA片断 ,将该片段克隆入质粒pVXORF1-HBS中HBS的上游并与之紧密相连 ,构建质粒 pVXORF1-PfMSP2 -HBS ;构建真核重组表达质粒 pVXORF1-PfMSP2 以作为对照。 (2 )用上述构建的质粒及空质粒 pVXORF1免疫KM小鼠 ,以ELISA检测血清IgG抗体。 结果　 (1)筛选出的重组子为编码FCC1/HNMSP2 基因片断的重组质粒 pVXORF1-PfMSP2 -HBS及 pVXORF1-PfMSP2 。 (2 )裸DNA尾根多点注射KM小鼠 ,显示 pVXORF1-PfMSP2 -HBS组小鼠较pVXORF1-PfMSP2 组小鼠产生抗PfMSP2 蛋白的抗体效价明显增高 ,二者比较 ,差异有非常显著意义 (P <0 0 1)。结论　PfMSP2 融合HBsAg基因片段激发机体产生抗PfMSP2 抗体的能力显著增强 ,提示PfMSP2 融合HBsAg基因有可能作为高效抗红内期恶性疟原虫复合多价基因疫苗的有效组成部分

Construction and immunogenicity in mice of eukaryotic expression recombinant plasmid expressing the Plasmodium falciparum merozoite surface protein 2 fused to HBS gene

Aim To construct recombinant plasmid of the southern China isolate FCC1/HN of Plasmodium falciparum bearing the gene coding for hybrid merozoite surface protein 2 fused to Hepatitis B virus gene as well as to exam the immune properties Methods (1) Using polymerase chain reaction (PCR) techique,the pfMSP 2 gene was amplified from genomic DNA of prokaryotic expression recombinant plasmid PET28 α pfMSP 2 of isolate FCC1/HN,then cloned into the plasmid pVXORF1 HBS,located the upstream of HBS and ligated directly Eukaryotic recombinant plasmid pVXORF1 PfMSP 2 HBS was constructed,as control,eukaryotic recombinant plasmid pVXORF1 PfMSP 2 was also constructed (2)Immunization of mice with the constructed plasmids above and non modified plasmid pVXORF1 Post immunization sera IgG was detected by ELISA Result Both the recombinant plasmid pVXORF1 PfMSP 2 HBS and pVXORF1 PfMSP 2 contained the MSP 2 gene from FCC1/HN isolate of Plasmodium falciparum The tites of antibody againsts PfMSP 2 immune with plasmid pVXORF1 PfMSP 2 HBS in mice has risen significantly Conclusion The protective antibody titers stimulating by Plasmodium falciparum bearing the gene coding for hybid merozoite surface protein 2 Hepatitis B virus gene fusion has risen significantly Plasmodium falciparum bearing the gene coding for hybrid merozoite surface protein 2 Hepatitis B virus gene fusion maybe used as the efficient component of a genetic vaccine against the asexual blood stages of plasmodium