摘要
目的阐明我国疟疾流行区间日疟原虫传播阻断疫苗候选抗原pvs25基因多态性特点。方法收集全年流行区云南省血样31份;提取疟原虫基因组DNA;聚合酶链反应(PCR)扩增pvs25基因;Sanger双脱氧链终止法测序;DnaSPversion4.0软件统计学分析。结果成功扩增pvs25全长基因31个序列。与标准株SalI比较,检测出4个错义突变位点,5种基因型,4处氨基酸置换。C103G289C389C391为主导基因型,L35E97T130Q131是相应主导氨基酸型,其突变与季节流行区的主导基因型和氨基酸型完全一致。核苷酸多态性π值为0.0014。组间多态性π值比较表明全年流行区明显高于季节流行区。结论我国分离株间日疟原虫传播阻断疫苗候选抗原Pvs25只有1种主导基因型和1种主导氨基酸型。有限的基因突变再次提示Pvs25是理想的候选抗原,以Pvs25为基础构建的传播阻断疫苗在我国具有广泛应用的可行性。
The genetic polymorphism of the candidate antigen pvs25 for transmission-blocking vaccine of vivax malaria isolated in China was investigated in the present study. Thirty one blood samples were collected in the epidemic area of malaria of Yunnan province, and the genomic DNA of malaria parasites was extracted from the blood samples. The pvs25 gene was amplified by PCR, and the PCR products were directly sequenced with data analyzed by DnaSP version 4.0 software. In the present study, the full length of pvs25 gene with 31 segments of sequences was successfully amplified. Compared with the Sal sequence of pvs25 gene, 4 non-synonymous mutation sites, 5 varieties of haplotype and 4 amino acid substitutions were detected, in which the C^(103)G^(289)C^(389)C^(391) was the predominant haplotype and L^(35)E^(97)T^(130)Q^(131) was the main type of amino acids, that were consistent with those of isolates in Zhejiang and Hubei provinces previously reported. The π value of genetic diversity was 0.0014, and the DNA divergence between populations found higher polymorphism in Yunnan isolates than in Zhejiang-Hubei isolates.It is concluded that there exist only one predominant haplotype and one main type of amino acids of the candidate antigen Pvs25 for the transmission blocking vaccine in the Chinese isolates. The limited gene mutation of Pvs25 reinforces the fact that Pvs25 is a good candidate antigen for the construction of the transmission blocking vaccine used in China.
出处
《中国人兽共患病杂志》
CSCD
北大核心
2005年第6期458-460,481,共4页
Chinese Journal of Zoonoses
基金
国家自然科学基金资助项目(No.30371347)
