Mahajan R C, Farooq Umar, Dubey M L, Malla N
Department of Parasitology, PGIMER, Chandigarh.
Indian J Pathol Microbiol. 2005 Oct;48(4):429-38.
Malaria is still a major public health problem in many tropical and subtropical countries. Malaria vaccine is highly desirable as an adjunct to existing malaria control measures. The polymorphisms in malaria vaccine candidates antigens might be a hurdle in developing an effective vaccine. The present article reviews the genetic polymorphism in several antigens expressed on the parasite surface, which are targets for immunological responses of the host and are good candidates for vaccine development against P. falciparum. Variable regions of most genes are generally dimorphic probably as a result of intragenic recombinations. Each allele in turn shows polymorphism resulting from point mutations, or other mechanisms. Several antigens like merozoite surface protein-1 and 2 (MSP-1 and MSP-2) and S antigen show high polymorphism while in others like circumsporozoite protein (CSP), apical membrane antigen-1 (AMA-1) and erythrocyte binding antigen-175 (EBA-175) functional constraints limit the degree of polymorphism. Polymorphism reported in these genes is discussed.
疟疾在许多热带和亚热带国家仍然是一个主要的公共卫生问题。疟疾疫苗作为现有疟疾控制措施的辅助手段非常必要。疟疾候选疫苗抗原的多态性可能是开发有效疫苗的一个障碍。本文综述了几种在寄生虫表面表达的抗原的遗传多态性，这些抗原是宿主免疫反应的靶点，也是开发抗恶性疟原虫疫苗的良好候选抗原。大多数基因的可变区通常是二态的，这可能是基因内重组的结果。每个等位基因又因点突变或其他机制而呈现多态性。几种抗原，如裂殖子表面蛋白-1和-2（MSP-1和MSP-2）以及S抗原，表现出高度多态性，而在其他抗原中，如环子孢子蛋白（CSP）、顶膜抗原-1（AMA-1）和红细胞结合抗原-175（EBA-175），功能限制限制了多态性的程度。本文讨论了这些基因中报道的多态性。
