新型疟疾传播阻断疫苗候选抗原PbPSOP7基因截短片段的克隆及表达特点的研究

Cloning and Expression Characteristics of Truncated Segment from Candidate Antigen PbPSOP7 Gene of a New Type Malaria Transmission-Blocking Vaccine

传播阻断疫苗(transmission-blocking vaccines,TBVs)可以有效地阻断疟原虫从蚊媒向人的传播,是控制疟疾流行的关键,但目前的TBVs候选抗原十分有限,迫切需要寻找有效的候选抗原。动合子分泌蛋白7(putative secreted ookinete protein 7,PSOP7)在疟原虫有性生殖阶段发挥着至关重要的作用,本研究对伯氏疟原虫抗原PSOP7(Pb PSOP7)进行简要的生物信息学分析,并应用原核表达系统高效表达纯化了截短的重组Pb PSOP7蛋白(r Pb PSOP7),免疫BALB/c小鼠后,获得小鼠高滴度多克隆抗体。经Western Blot方法证实该多克隆抗体可识别疟原虫抗原。间接免疫荧光实验显示,Pb PSOP7主要表达于疟原虫的合子与动合子表面。这些特点符合TBVs的基本设计理念,为确认和证实Pb PSOP7蛋白具有疟疾TBVs候选抗原的潜能奠定基础。

Transmission-blocking vaccines（TBVs） could effectively block the transmission from malarial parasite into human body,it is a crux to control the epidemic of malaria,however,at present the candidate antigen is very limited,and it is very urgent to search effective candidate antigens.PSOP7（putative secreted ookinete protein 7） plays most important role in plasmodial sexual reproduction stage.Bioinformatic analysis of Plasmodium berghei antigen PSOP7（Pb PSOP7） was carried out in this study,and expressed purified truncated recombinant Pb PSOP7 protein r Pb PSOP7 using prokaryotic expression system,after immuned on BALB / C mice,and obtained mouse high titter poly-clonal antibody.It was proved that the polyclonal antibody could identify plasmodial antigen through Western Blot.Indirect immuno-fluorescence experiment had showed that the Pb PSOP7 mainly expressed on the surfaces of zygote and ookinete.These features accorded with the design of the basic idea of TBVs,and laid a foundation for the potential of confirmation and provement of the Pb PSOP7 protein possesses TBVs candidate antigen.