我国HIV/AIDS患者感染人芽囊原虫的基因多态性和致病性研究

项目名称： 我国HIV/AIDS患者感染人芽囊原虫的基因多态性和致病性研究

项目编号： No.81473022

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 医药、卫生

项目作者： 田利光

作者单位： 中国疾病预防控制中心寄生虫病预防控制所

项目金额： 60万元

中文摘要： 人芽囊原虫是一种常见的寄生于人体肠道的原虫，其感染呈世界性分布，在婴幼儿、免疫力低下、HIV感染者以及免疫缺陷人群中该原虫感染率较高。人芽囊原虫的致病性尚存在争议，目前普遍认为人芽囊原虫为机会性致病原虫，当机体抵抗力下降或免疫功能不全时，其繁殖能力和致病性增强，可引起明显的临床症状和体征。艾滋病人群感染人芽囊原虫可能会引起较严重的腹泻症状，甚至死亡。近年来基因检测分析显示人芽囊原虫存在9种或更多亚种，人芽囊原虫的致病与否或强弱与该虫的基因型有关。国内对人芽囊原虫分离株的基因多态性及生物学特性的研究甚少。HIV/AIDS患者感染的人芽囊原虫不同基因型及其对HIV/AIDS病程进展的影响还未见研究报道。本研究拟通过流行病学和分子生物学的方法，在HIV/AIDS患者中开展人芽囊原虫的基因多态性研究，探索人芽囊原虫不同基因型与其致病性以及感染不同基因型人芽囊原虫对HIV/AID病程进展的影响。

中文关键词： 艾滋病；人芽囊原虫；基因多态性；致病性

英文摘要： Blastocystis hominis is an anaerobic unicellular eukaryote that can inhabit the intestinaltrack of humans.Numerous cross-secctional surveys have been carried out in different epidemiological settings and hence B.hominis is known to be one of the most frequently found protozoan parasites in human faecal samples, especialy in children, immunocompetent and immunocompromise patients including cancer and HIV/AIDS. Yet, many aspects of this organism remain to be elucidated, including its taxonomy, speciation, pathogenetic potential, life cycle and mode of transmission.Human infections with B.hominis are called Blastocystosis and it present in both asymptomatic and symptomatic in dividuals.Now widely recognized that B. hominis is an opportunistic pathogenic protozoan，When the body's defenses are weakened or immune dysfunction, its reproductive capacity and enhanced pathogenicity, can cause significant clinical symptoms.HIV/AIDS patients co-infected with B. hominis may cause more severe diarrhea and even death.Genotpic varialility has been reported to play an influential role in the pathogenicity of B.hominis.Different sub types of B.hominis may potentially be the pathogenic one.there are at least 9 sub types of B.hominis have been identified.Subtype 3 and 1 have been speculated to cause gastrointestinal symptoms,however, no compelling evidence exists for theis association.its pathogenic role has not been clearly defined.There are some studys on morphology of B.hominis have been carried out in China.Moreover, little is known about the genetic diversity of B. hominis and the pathogenetic potention of different subtypes in China.In 2009, we conducted research in the HIV/AIDS patients shows B. hominis prevalence rate was 17%,much higher than the general population.Here we conducted a molecular epidemiological survey on B. hominis in HIV/AIDS patients in China. The objectives of the present study were (i) to determine the prevalence of B. hominis in HIV/AIDS patients in China; (ii) to assess the relative frequency of different B. hominis subtypes and the pathogenetic; and (iii) to explore the impact on HIV / AIDS progression in patients coinfected with different genotypes B.hominis.

英文关键词： HIV/AIDS;Blastocystis hominis;genetic polymorphis;pathogenicity