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  

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

作　　者：郑丽[1] 徐卫民[2] 刘英杰[3] 杨毅梅[4] 曹雅明[1] 

机构地区：[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

出　　处：《中国寄生虫学与寄生虫病杂志》2004年第1期16-19,共4页Chinese Journal of Parasitology and Parasitic Diseases

基　　金：国家自然科学基金 (No 30 0 70 71 8)~~

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Pvs2 5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Pvs2 5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 ,Pvs2 5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 ,Pvs2 5具有有限的抗原多态性 ,提示以Pvs2Objective 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.

关 键 词：间日疟原虫 传播阻断疫苗 基因多态性 Pvs25抗原 聚合酶链反应 

分 类 号：R531.3[医药卫生—内科学] R446.62[医药卫生—临床医学]