Analysis of the macrophage membrane proteome: effects of viral infection

 描述(申请人提供)：HCMV是一种β-疱疹病毒，在受感染宿主的一生中作为一种持续性感染而存在。从历史上看，感染这种病毒会对免疫功能受损的人构成威胁，包括艾滋病患者和接受器官移植的人。这种病毒无处不在，大多数成年人在40岁之前感染。在健康宿主中，感染的急性期是自我限制的，病毒建立了一种潜伏感染，可以 在应对各种细胞压力时被重新激活。髓系细胞是病毒的储存库。人巨细胞病毒感染可诱导慢性炎症，因此，人巨细胞病毒持续感染在心血管疾病、癌症等炎症性疾病的发病机制中的作用一直是众多研究的热点。巨细胞病毒在感染细胞的细胞质中获得一个脂膜，但对感染对脂类代谢和转运的影响知之甚少。我们之前已经证明，感染阻止了THP-1来源的巨噬细胞转化为富含脂质的泡沫细胞，以回应氧化型低密度脂蛋白的治疗。随后，我们观察到病毒抑制了细胞与脂蛋白结合的能力，以及 细胞表面清道夫受体介导的相互作用。我们的研究表明，感染可能破坏质膜上的脂筏微区，从而抑制清道夫受体的功能。这个项目的最终目标是了解控制脂筏稳定性和HCMV感染细胞清道夫受体功能的机制。为了实现这一目标，我们将研究感染后质膜组成的变化，并通过对脂筏稳定性的影响来确定毒蛇毒素、ABCA1和SR-BI在调节受体活性中的作用。本研究将为今后的工作奠定基础。

 DESCRIPTION (provided by applicant): HCMV is beta-herpesvirus and is maintained for the lifetime of the infected host as a persistent infection. Historically, infection with this virus poes a threat to the immunocompromised, including patients with AIDS and those receiving organ transplants. The virus is ubiquitous and most adults are infected by age 40. In the healthy host, the acute phase of infection is self-limiting and the virus establishes a latent infection that can be reactivated in response to a variety of cellular stresses. Cells of the myeloid lineage are the reservoir for the virus. HCMV infection induces chronic inflammation; thus, the role of HCMV persistence in the pathology of diseases with inflammatory components, such as cardiovascular disease and cancer, is the focus of many studies. HCMV acquires a lipid envelope in the cytoplasm of infected cells but little is known about the effects of infection on lipid metabolism and trafficking. We have previously shown that infection blocked the conversion of THP-1 derived macrophages into lipid-laden foam cells in response to treatment with oxidized LDL. Subsequently, we observed that the virus inhibited the ability of cells to bind the lipoprotein, an interaction mediated by scavenger receptors on the cell surface. Our studies indicate that infection likely disrupts lipid raft microdomains on the plasma membrane and thereby inhibits scavenger receptor functions. The ultimate goal of this project is to understand the mechanisms that control lipid raft stability and scavenger receptor function in HCMV- infected cells. To accomplish this goal we will investigate changes in plasma membrane composition after infection and determine the roles of viperin, ABCA1, and SR-BI in regulation of receptor activity through their effects on lipid raft stability. The present studies will provide the foundation for future work.