中国寄生虫学与寄生虫病杂志 ›› 2004, Vol. 22 ›› Issue (1): 5-19.

• 论著 • 上一篇    下一篇

间日疟原虫传播阻断疫苗候选抗原Pvs25中国分离株高度保守

郑丽1,徐卫民2,刘英杰3,杨毅梅4,曹雅明1

  

  1. 1 中国医科大学免疫学教研室,沈阳 110001 ; 2 杭州市疾病预防控制中心, 杭州 310000; 3 中国医科大学病原生物学教研室,沈阳110001; 4 大理医学院寄生虫学教研室 ,大理 671000
  • 收稿日期:1900-01-01 修回日期:1900-01-01 出版日期:2004-02-28 发布日期:2004-02-28

Transmission-blocking Vaccine Candidate of Plasmodium vivax Pvs25 Is Highly Conservative among Chinese Isolates

ZHENG Li1;XU Wei-min2;LIU Ying-jie3;YANG Yi-mei4;CAO Ya-ming1   

  1. 1 Department of Immunology,China Medical University,Shenyang 110001,China
  • Received:1900-01-01 Revised:1900-01-01 Online:2004-02-28 Published:2004-02-28

摘要:

目的 研究我国单纯间日疟流行区 3 1例患者 (湖北18例、浙江13例 )间日疟原虫分离株传播阻断疫苗候选抗原Pvs2 5基因多态性 ,并与 14例孟加拉间日疟原虫株进行比较分析。 方法 从干燥滤纸血膜提取疟原虫基因组DNA ,对Pvs25基因进行聚合酶链反应 (PCR)扩增、纯化和直接序列分析。 结果 与间日疟原虫标准株Sal-I相比 ,获得的 45个Pvs25全长序列中有 3处点突变 ,引起相应氨基酸的替换。并且核苷酸多态性 (π值 )检验结果显示 ,Pvs25在不同流行区或同一流行区不同分离株之间核苷酸及其相应的氨基酸序列高度保守。 结论 与红前期和红内期候选抗原相比 ,Pvs25具有有限的抗原多态性 ,提示以Pvs25为基础构建的传播阻断疫苗在我国流行区具有普遍应用的可能性

关键词: 间日疟原虫, 传播阻断疫苗, Pvs25抗原, 基因多态性

Abstract:

Objective To investigate the genetic diversity of Plasmodium vivax transmission-blocking vaccine candidate antigen (TBV) Pvs25, with P.vivax isolates from Hubei and Zhejiang Provinces, and to compare the genetic polymorphism of Pvs25 with that from Bangladesh. MethodsThe parasite DNA used for the genetic polymorphism assay was obtained from dried filter paper blood spots. The genes were PCR amplified and the products were purified and sequenced directly. Results 45 complete new sequences were analyzed. Only 3 nucleotide changes were found that would result in amino acid substitutions in Pvs25 in comparison with the sequence from P.vivax Sal-I strain. The measurement of nucleotide diversity (π) was remarkably similar for the two populations, indicating that DNA sequences and deduced amino acid sequences were highly homologous among the geographically dispersed isolates or isolates from the same geographical region.Conclusion The results suggest that Pvs25 has limited antigenic polymorphism, especially compared with candidate antigens expressed by hepatic and erythrocytic stage, which may support the development and application of Pvs25-based transmission-blocking vaccine in China.

Key words: Plasmodium vivax, transmission-blocking vaccine, Pvs25, genetic polymorphism