印度北部和西北部地区间日疟原虫 merozoite 表面蛋白-1 基因的多态性。

Polymorphism in merozoite surface protein-1 gene in north & northwest Indian field isolates of Plasmodium vivax.

机构信息

Department of Parasitology, Postgraduate Institute of Medical Education & Research, Chandigarh 160 012, India.

出版信息

Indian J Med Res. 2009 Dec;130(6):736-41.

PMID:20090136

Abstract

BACKGROUND & OBJECTIVE: Merozoite surface protein-1 of Plasmodium vivax (Pvmsp-1) is a strong vaccine candidate against asexual blood stages. Extensive polymorphism in msp-1 gene has been reported in P. vivax isolates from different geographical regions which is necessary before a field trial of any malaria vaccine based on msp-1 is undertaken. There are only a few reports available on polymorphism in msp-1 gene in Indian field isolates of P. vivax. The aim of the present study was therefore to investigate the polymorphism in Pvmsp-1 gene in 25 isolates of P. vivax collected from malaria patients from regions of north and northwest India.

METHODS

DNA was extracted from whole blood samples collected in citrated anticoagulant. The polymorphic region-5, the most variable region of the Pvmsp-1 gene was amplified by PCR. The PCR products were further analyzed by restriction fragment length polymorphism (RFLP) using Mva-1 restriction enzyme. The DNA fragments obtained on PCR and RFLP were analyzed by agarose gel electrophoresis.

RESULTS

On the basis of PCR, significant size polymorphism was seen and 4 allelic types were observed amongst the 25 isolates. Further analysis by RFLP discriminated these 4 allelic types into 9 sub-allelic types indicating that PCR-RFLP can be a good tool to study polymorphism in msp-1 gene of Plasmodium.

INTERPRETATION & CONCLUSION: Marked genetic polymorphism was observed in msp-1 gene among the isolates of P. vivax. These observations stress the need to study larger numbers of isolates from different regions of India. The findings could have important implications on the vaccine development strategies for P. vivax.

摘要

背景与目的

间日疟原虫（Plasmodium vivax）裂殖子表面蛋白-1（Pvmsp-1）是一种针对无性血期的强力疫苗候选物。在不同地理区域的间日疟原虫分离株中，已经报道了 msp-1 基因的广泛多态性，这是在基于 msp-1 的任何疟疾疫苗进行现场试验之前必须进行的。关于印度间日疟原虫田间分离株中 msp-1 基因的多态性，仅有少数报道。因此，本研究旨在调查来自印度北部和西北部疟疾患者的 25 株间日疟原虫分离株中 Pvmsp-1 基因的多态性。

方法

从枸橼酸盐抗凝全血样本中提取 DNA。通过 PCR 扩增 Pvmsp-1 基因的多态性区域-5，这是 Pvmsp-1 基因中最具变异性的区域。使用 Mva-1 限制酶对 PCR 产物进行进一步的限制性片段长度多态性（RFLP）分析。通过琼脂糖凝胶电泳分析 PCR 和 RFLP 获得的 DNA 片段。