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采用基因工程技术，将编码恶性疟原虫有性期特异抗原Ｐｆｓ８／４５的基因克隆到真核表达质粒ｐｃＤ－ＮＡ３，并进行ＤＮＡ序列测定，再通过磷酸钙—ＤＮＡ共沉淀转化法将重组质粒ｐｃＤＮＡ３－ｐＦＳ４８／４５导入ＨｅＬａ细胞，建立稳定分泌Ｐｆｓ４８／４５蛋白的阳性克隆株。结果显示，我国海南ＦＣＣ１／ＨＮ株Ｐｆｓ４８／４５抗原基因序列与ＮＦ５４株者高度同源，提示该基因在不同虫株间高度保守，是研制疟疾疫苗的理想靶抗原；在ＨｅＬａ细胞中表达的Ｐｆｓ４８／４５蛋白分子量约为４６／４３．５ｋＤａ双联体蛋白，其表达量占细胞培养上清蛋白总量的１８．２７％。经ＷｅｓｔｅｒｎＢｌｏｔ分析显示，表在蛋白能被配子体免疫鼠血清特异性识别，提示表达的重组蛋白Ｐｆｓ４８／４５具有免疫活性。真核表达系统ｐｃＤＮＡ３／Ｐｆｓ４８／４５／ＨｅＬａ的建立为进一步研究重组Ｐｆｓ４８／４５抗原的免疫原性和保护性奠定基础。
The gene encoding P. falciparum Ps8 / 45 with the sex-specific antigen was cloned into the eukaryotic expression plasmid pcD-NA3 using gene engineering technology, and the DNA sequence was determined. The recombinant plasmid pcDNA3 -pFS48 / 45 into HeLa cells to establish a stable clone secreting Pfs48 / 45 protein. The results showed that the sequence of Pfs48 / 45 antigen in Hainan FCC1 / HN strain was highly homologous with that of NF54 strain, suggesting that this gene is highly conserved among different insect strains and is an ideal target antigen for the development of malaria vaccine. The expression of Pfs48 / 45 protein has a molecular weight of about 46 / 43.5kDa doublet protein, and its expression amount accounted for 18.27% of the total amount of cell culture supernatant protein. Western Blot analysis showed that the protein was specifically recognized by the serum of gametophytic mice, suggesting that the expressed recombinant protein Pfs48 / 45 was immunocompetent. The establishment of eukaryotic expression system pcDNA3 / Pfs48 / 45 / HeLa laid the foundation for further study on the immunogenicity and protection of recombinant Pfs48 / 45 antigen.