Molecular Determinants of Sporozoite / Host Cell Interactions

子孢子/宿主细胞相互作用的分子决定因素

• 批准号: 10192640
• 负责人: Stefan HI Kappe
• 金额: $ 47.08万
• 依托单位: SEATTLE CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-07-09 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10192640
• 关键词: Affinity Chromatography; Architecture; Bacterial Adhesins; Binding; Bite; Blocking Antibodies; Blood; Blood Cells; CD81 gene; Cell Communication; Cell Surface Receptors; Cell membrane; Cells; Cessation of life; Clinical; Complex; Culicidae; Data; Development; Disease; EphA2 Receptor; Epitopes; Erythrocytes; Future; Goals; Hepatocyte; Human; Infection; Intervention; Invaded; Link; Liver; Maintenance; Malaria; Maps; Mediating; Membrane; Membrane Proteins; Methods; Molecular; PDGFRB gene; Parasites; Parasitic infection; Pathway interactions; Plasmodium; Platelet-Derived Growth Factor beta Receptor; Process; Proteins; Publishing; Receptor Cell; Role; Site; Skin; Skin Tissue; Sporozoites; Stream; Surface; Symptoms; TRAP Complex; Travel; Vacuole; Work; base; cell motility; design; disease transmission; effective intervention; global health; in vivo; liver infection; malaria infection; novel; novel strategies; prevent; protein complex; receptor; small molecule inhibitor; spatiotemporal; therapy design; transmission process; vector mosquito

PROJECT SUMMARY/ABSTRACT Malaria, caused by Plasmodium parasites, continues to be a major global health problem, with more than 200 million new infections and nearly 500 thousand deaths annually. Infection initiates when sporozoite stages are inoculated into the skin by the mosquito vector. Sporozoites then move in the skin tissue, enter the blood stream and reach the liver. Sporozoites traverse cells before eventually infecting a hepatocyte within a replication-permissive parasitophorous vacuole (PV). Ensconced in the PV membrane (PVM), a single sporozoite will transmogrify into a liver stage that replicates and then forms tens of thousands of merozoites. These are released from the liver and infect and replicate in blood cells, which causes all clinical symptoms of malaria and enables further parasite transmission. Targeting the pre-erythrocytic sporozoites thus represents an attractive intervention point since they are small in number, and successful disruption of the molecular interactions required for infection would completely prevent disease and transmission. However, little is known about the critical molecular interactions leading to productive sporozoite entry into the host, infection of the liver and invasion of hepatocytes. In this proposal, using novel approaches, we will focus on elucidating the molecular map of infection that involves the sporozoite protein complexes containing P52, P36 and the TRAP complex, and their interactions with the host receptors EphA2, CD81 and PDGFR, respectively. Currently we only know that P36 and P52 are essential for establishing productive hepatocyte infection with a PVM and that the hepatocyte surface receptors EphA2 and CD81 are critical for PVM formation as well. In Aim 1, we will investigate the dynamics and conditions of release of P52 and P36 from sporozoites during interaction with hepatocytes. Following our preliminary isolation of a P52/P36 complex, we will proceed to determine the precise molecular interactions within this complex and its interaction with EphA2, CD81 and any other novel putative receptor(s) identified. In Aim 2, we will focus on the hepatocyte surface to further study the functional significance of EphA2 during hepatocyte invasion and PV formation as well as its relationship to CD81 and novel receptors. In Aim 3, we will investigate a novel parasite-host interaction pair identified by us between host protein PDGFR and the sporozoite adhesin TRAP, and the importance of this interaction for host infection in the context of a large TRAP-containing sporozoite protein complex that we have recently identified. Upon completion of the proposed work we will have a clear molecular map of the interactions of critical sporozoite invasion-related protein complexes and host receptor complexes. This data will be important to design targeted interventions such as infection-blocking antibodies or small molecule inhibitors and as such will contribute to the goal of preventing malaria infection.

项目摘要/摘要 由疟原虫寄生虫引起的疟疾仍然是一个主要的全球健康问题，有200多个 每年有百万个新感染和近50万个死亡。 通过蚊子接种到皮肤中。 流向肝脏，在最终感染肝细胞之前 复制 - 抗寄生虫液泡（PV）。 Sporozoite将转移到复制和成千上万的梅罗佐氏菌的肝脏阶段。 这些是从肝脏中释放出来的，并在血细胞中感染并复制，这会导致所有临床症状 疟疾并实现进一步的寄生虫转移。 一个有吸引力的干预点，因为它们的数量很小，并且成功破坏了 感染所需的相互作用将完全预防疾病和传播。 关于临界分子相互作用与生产生产性孢子虫属于宿主的生产性孢子虫感染 和肝细胞的发明。 分子图涉及竞争性p52，p36和陷阱的孢子岩蛋白 复合物以及与宿主受体Epha2，CD81和PDGFR的相互作用，分别是我们。 只知道p36和p52是用PVM建立生产性肝感染的明显的 肝细胞表面受体Epha2和CD81对于AIM 1中的PVM形成至关重要。 在与Sporozoits释放p52和p36的动态和条件 肝细胞。 在该复合物中的精确分子相互作用，与Epha2，CD81和任何其他新型的相互作用 推定的受体在AIM 2中确定，我们将重点放在肝细胞表面上 肝细胞和PV形成过程中EPHA2的重要性以及与CD81的关系 新的受体。 宿主蛋白PDGFR和Sporozoite粘附蛋白陷阱，以及这种相互作用对家庭的重要性 在我们最近确定的含大型捕获诱捕的孢子素蛋白蛋白复合物的背景下，感染。 在压缩支撑工作后，我们将有一个清晰的分子图 Sporozoite Invision相关的蛋白质复合物和宿主受体复合物。 设计有针对性的型或小分子抑制剂，因此将会 有助于预防疟疾感染的目标。