间日疟原虫中国湖北分离株传播阻断疫苗候选抗原Pvs 28的基因多态性分析

从间日疟原虫感染患者血样制备的干滤纸片中提取寄生虫基因组DNA,以实验室Sall株的Pvs28基因序列设计合成特异性引物,以各分离株基因组DNA为模板,采用PCR技术扩增间日疟原虫传播阻断疫苗候选抗原Pvs28基因全长,其大小为696Bp的片段,将PCR产物直接测序.所获得的序列用Mac Vector软件分析并以Sall株为标准进行突变比较.结果表明,该Pvs28基因在核苷酸水平共存在两种突变形式,即3个点突变与5～7个不同数目的重复片段.点突变情况与我们以前的研究相同,但重复片段数目5和7与以前报道有差异.本文是对我国间日疟原虫单纯流行区湖北省疟原虫分离株传播阻断疫苗候选抗原Pvs28基因多态性的首次报导,研究结果为我国间日疟原虫传播阻断疫苗的实际开发与应用提供了必需的前提依据.

GENETIC POLYMORPHISM ANALYSIS OF THE TRANSMISSION BLOCKING VACCINE CANDIDATE ANTIGEN Pvs28 FROM PLASMODIUM VIVAX ISOLATES FROM HUBEI, CHINA

To investigate the genetic diversity of P.vivax transmission blocking vaccine candidate antigen Pvs28 from 15 isolates of P.vivax in single endemic regions of Hubei Province,China.The parasite DNAs used for the genetic polymorphism assay were obtained from dired on blood spots filter papers.The genes were amplified by PCR and the products were purified,cloned and sequenced.15 complete new sequences were reported.Two types of mutation were found including 3 nucleotide changes that would result in 2 amino acid substitutions and different numbers of repeat fragments range from 5 to 7.These results of Pvs28 antigenic polymorphisms were reported for the first time in China,which supply a necessary basic data for the development and application of transmission blocking vaccine against malaria based on Pvs28.