Molecular Analysis of the PfEMP1 Binding Activity

PfEMP1 结合活性的分子分析

• 批准号: 7740795
• 负责人: JOSEPH D SMITH
• 金额: $ 41.74万
• 依托单位: SEATTLE BIOMEDICAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-07-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7740795
• 关键词: Adhesions; Adhesives; Affect; Antigenic Variation; Binding; Biological Assay; Blood Vessels; Brain; Cells; Clinical; Cloning; Communicable Diseases; Disease; Endothelial Cells; Endothelium; Erythrocyte Membrane; Erythrocytes; Falciparum Malaria; Family; Genes; Genetic; Genetic Variation; Genotype; Grant; Heart; Infection; Laboratories; Lung; Malaria; Membrane Proteins; Molecular; Molecular Analysis; Organ; Parasites; Pathogenesis; Phenotype; Placenta; Plasmodium falciparum; Pregnancy; Property; Protein Binding; Proteins; Recombinant Proteins; Recombinants; Research; Research Personnel; Reverse Transcription; Serum; Specificity; Surface; Testing; Time; Tropism; Variant; Virulence Factors; base; cell type; design; functional group; gene conservation; human disease; parasite genome; programs; receptor

Malaria caused by Plasmodium falciparum is one of the most important infectious diseases of humankind. Each year there is an estimated 300-660 million episodes of clinical P. falciparum malaria and 1-2 million will die from the infection. In P. falciparum, the family of var genes encode erythrocyte membrane proteins (PfEMPI), which act as virulence factors responsible for both antigenic variation and binding of infected erythrocytes to endothelium. Each parasite genome encodes approximately 60 PfEMPI proteins that differ between parasite strains and bind different host receptors. Severe malaria occurs when infected erythrocytes sequester in brain or placenta. The specific hypothesis behind the proposed research is that particular adhesive types may predispose to severe malaria because of their binding tropism. This study will determine the binding properties of PfEMPI proteins and how they affect infected erythrocyte selectivity for different microvascular endothelial cells. PfEMPI binding will be studied from a well characterized parasite isolate that has been adapted to grow in the laboratory. Parasite lines expressing specific PfEMPI variants will be generated by limited dilution cloning or by selection on different host receptors. Real-time PCR approaches with gene-specific primers to the family of var genes will be used to define the var genes expressed in the various lines. The specific adhesion properties of each PfEMPI protein will be determined by characterizing infected erythrocyte adhesion against an extensive panel of host receptors and microvascular endothelial cells. These studies will contribute to a detailed characterization of the cytoadhesive properties of a parasite and enable a greater understanding of the molecular basis of malaria pathogenesis.

由恶性疟原虫（Plasmodiumfalciparum）引起的疟疾是人类最重要的传染病之一。 据估计，每年有3亿至6.6亿例恶性疟原虫疟疾临床病例， 死于感染在恶性疟原虫中，var基因家族编码红细胞膜蛋白 （PfEMPI），其作为毒力因子，负责抗原变异和感染的 红细胞到内皮细胞。每个寄生虫基因组编码大约60种PfEMPI蛋白， 并结合不同的宿主受体。严重的疟疾发生在感染 红细胞在脑或胎盘中隔离。拟议研究背后的具体假设是， 特定的粘附类型由于它们的结合向性而可能易患严重疟疾。本研究将 确定PfEMPI蛋白的结合特性以及它们如何影响感染的红细胞对 不同的微血管内皮细胞。将从充分表征的寄生虫中研究PfEMPI结合 已适应在实验室中生长的分离物。表达特异性PfEMPI变体的寄生虫系 将通过有限稀释克隆或通过在不同宿主受体上选择来产生。实时pcr 将使用针对var基因家族的基因特异性引物的方法来定义var基因 用不同的线条来表达。将测定每种PfEMPI蛋白的特异性粘附特性 通过表征受感染的红细胞对大量宿主受体的粘附， 微血管内皮细胞这些研究将有助于详细描述 寄生虫的细胞粘附特性，并使人们能够更好地了解疟疾的分子基础 发病机制