Functional analysis of erythrocyte determinants of malaria infection

疟疾感染红细胞决定因素的功能分析

• 批准号: 8183448
• 负责人: Manoj T Duraisingh
• 金额: $ 40.38万
• 依托单位: HARVARD SCHOOL OF PUBLIC HEALTH
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8183448
• 关键词: Affect; Anti-malarial drug resistance; Antimalarials; Binding Proteins; Biochemical; Biological; Blood Circulation; Blood Group Antigens; Blood typing procedure; Cell surface; Cessation of life; Childhood; Clinical; Communicable Diseases; Development; Disease; Drug resistance; Environment; Erythrocytes; Gene Targeting; Genes; Genetic; Genetic Polymorphism; Genetic Screening; Glycophorin A; Goals; Growth; Hematopoietic stem cells; Homologous Protein; Human; Human Pathology; Immune; In Vitro; Individual; Infection; Intervention; Knock-out; Lead; Life; Ligands; Malaria; Measures; Membrane Proteins; Molecular Genetics; Parasites; Pathway interactions; Pharmaceutical Preparations; Plasmodium falciparum; Play; Population; Process; Proteins; RNA Interference; Regimen; Relative (related person); Resources; Reticulocytes; Role; Stem cells; Subfamily lentivirinae; Surface; System; Vaccines; Variant; Work; antigen binding; base; blood group; combinatorial; design; erythrocyte receptor; genetic analysis; loss of function; loss of function mutation; member; mortality; mutant; novel; novel strategies; novel therapeutics; parasite invasion; positional cloning; receptor; response; therapeutic target; vaccine candidate; vaccine development

DESCRIPTION (provided by applicant): Malaria remains a major global infectious disease, largely affecting people living in resource poor environments, and is one of the most important causes of childhood mortality. Drug-resistance is constantly undermining the usefulness of antimalarial regimens. There is an urgent need for the development of new therapeutic strategies. Plasmodium falciparum parasites utilize multiple ligand-receptor interactions for the invasion of human erythrocytes. Much work has focused on the characterization of parasite ligands, with the goal of developing them as vaccine candidates. Largely due to the genetic intractabiliy of enucleated human erythrocytes, the function of host human erythrocyte receptors in ligand-receptor interactions has not been comprehensively assessed. We have developed an approach combining an in vitro erythrocyte culture system, which supports P. falciparum invasion and growth, with lentiviral transduction to generate genetically modified erythrocytes. The best characterized ligand-receptor interaction in P. falciparum is that of the ligand EBA-175 and its receptor glycophorin A, with EBA-175 being developed as a vaccine candidate. Using this system, we have achieved knockdown in expression of glycophorin A, genetically demonstrating that it is required for efficient strain-specific parasite invasion. We hypothesize that targeting a limited number of erythrocyte receptors will be sufficient to abrogate P. falciparum invasion in all P. falciparum parasite lines. This project will functionally analyze erythrocyte determinants of the invasion process of P. falciparum. We will use 1) a loss-of- function approach to establish a hierarchy amongst putative erythrocyte receptors for invasion, 2) a combinatorial knockdown approach to identify minimal sets of erythrocyte surface determinants that are essential for invasion and 3) a genetic screen to identify human blood group antigens that are novel determinants of invasion. In the long-term we hope that our studies will provide a functional understanding of critical ligand-receptor interactions for P. falciparum invasion of erythrocytes to inform vaccine development and the design of host-targeted therapeutics. PUBLIC HEALTH RELEVANCE: Malaria parasites interact intimately with molecules on the red blood cell surface of the human host during invasion and growth. The identity of host molecules that are essential for malaria proliferation has remained elusive. We will use a novel approach of genetically manipulating stem cells to study the function of molecules in the host red blood cell. We hypothesize that the identification and analysis of essential host proteins will provide ideal candidates for the development of novel therapeutics and will greatly inform vaccine development.

描述（由申请人提供）：疟疾仍然是一种主要的全球传染病，在很大程度上影响了生活在资源贫困环境中的人们，并且是儿童死亡率最重要的原因之一。抗药性不断破坏抗疟疾方案的有用性。迫切需要制定新的治疗策略。恶性疟原虫寄生虫利用多种配体 - 受体相互作用来侵袭人红细胞。许多工作集中在寄生虫配体的特征上，目的是将其作为候选疫苗发展。在很大程度上，由于人类红细胞的遗传性侵入性，尚未全面评估宿主人类红细胞受体的宿主人红细胞受体的功能。我们已经开发了一种结合体外红细胞培养系统的方法，该系统支持恶性疟原虫的侵袭和生长，以及慢病毒转导，以产生转基因修饰的红细胞。恶性疟原虫中最好的配体 - 受体相互作用是配体EBA-175及其受体糖蛋白A，其EBA-175被发展为疫苗候选者。使用该系统，我们已经在糖蛋白A的表达中实现了敲低，从而证明这是有效的菌株特异性寄生虫侵袭所必需的。我们假设靶向有限数量的红细胞受体将足以消除所有恶性疟原虫寄生虫线中的恶性疟原虫入侵。该项目将在功能上分析恶性疟原虫入侵过程的红细胞决定因素。我们将使用1）一种功能丧失方法来在推定的红细胞受体之间建立层次结构以进行入侵，2）一种组合敲低方法，以识别最小的红细胞表面决定因素，该方法是入侵和3）遗传筛选的遗传筛查，以识别出入侵的遗传性人类血型抗体。从长远来看，我们希望我们的研究能够提供对临界配体 - 受体相互作用的功能理解，以使恶性疟原虫入侵红细胞，以告知疫苗的开发和宿主靶向的治疗剂的设计。 公共卫生相关性：疟疾寄生虫在入侵和生长过程中与人类宿主的红细胞表面上的分子密切相互作用。对于疟疾增殖所必需的宿主分子的身份仍然难以捉摸。我们将使用一种新型的遗传操纵干细胞的方法来研究宿主红细胞中分子的功能。我们假设，对基本宿主蛋白的识别和分析将为开发新的治疗剂提供理想的候选者，并将大大为疫苗开发提供大量信息。