Cellular Determinants of Hantavirus Pathogenesis

汉坦病毒引起两种高致死性的人类疾病，肾综合征出血热（HFRS）和汉坦病毒肺综合征（HPS），并有可能被用作生物恐怖剂。汉坦病毒主要在内皮细胞中复制，但对受感染的内皮细胞不造成明显损伤。非致病性汉坦病毒也感染人内皮细胞，表明细胞内事件决定汉坦病毒致病的能力。使用DNA阵列，我们发现非致病性汉坦病毒前景希尔病毒（PHV）在内皮细胞内快速诱导干扰素（IFN）应答，而致病性汉坦病毒（HTNV）（HFRS）或纽约-1病毒（NY-1V）（HPS）不诱导该应答。PHV复制因此被抑制，而HTNV和NY-1V在人内皮细胞内复制。此外，PHV和NY-1V的共感染降低了PHV导向的IFN应答，表明NY-1V负调节防御性细胞应答。这些发现表明，致病性和非致病性汉他病毒差异调节先天性细胞防御，并表明致病性汉他病毒改变内皮细胞反应的能力是汉他病毒发病机制的基本决定因素。虽然没有关于汉坦病毒蛋白如何指导或调节IFN应答的信息，但我们最近 确定汉坦病毒蛋白质相互作用，可能会影响干扰素的反应。我们的初步结果表明，致病性汉坦病毒蛋白发挥作用，阻断细胞防御，从而允许致病性汉坦病毒在内皮细胞内复制。目的：研究致病性和非致病性血管内皮细胞对内皮细胞反应的不同调节， 非致病性汉坦病毒。我们将定义抑制IFNb反应的汉他病毒蛋白，并确定IRF-3和NF-kB激活对汉他病毒复制的作用，以确定致病性汉他病毒调控的信号通路和蛋白质。这些实验提供了对汉坦病毒调节先天免疫缺陷的基本理解。 细胞防御，确定汉他病毒发病机制的决定因素，并有望为汉他病毒疾病干预提供治疗靶点。特定目的：目的1）确定调节细胞IFN应答的汉坦病毒蛋白。目的2）探讨致病性汉坦病毒对信号通路的调控机制。

Hantaviruses cause two highly lethal human diseases, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS), and have the potential to be used as bioterrorism agents. Hantaviruses replicate predominantly in endothelial cells but cause no apparent damage to the infected endothelium. Non-pathogenic hantaviruses also infect human endothelial cells, indicating that intracellular events determine the capacity for hantaviruses to cause disease. Using DNA arrays we have found that the non-pathogenic hantavirus Prospect Hill Virus (PHV) rapidly induces interferon (IFN) responses within endothelial cells that are not elicited by pathogenic Hantaan virus (HTNV) (HFRS) or New York-1 virus (NY-1V) (HPS). PHV replication is consequently inhibited while HTNV and NY-1V replicate within human endothelial cells. In addition, co-infection of PHV and NY-1V reduced PHV-directed IFN responses, suggesting that NY-1V negatively regulates defensive cellular responses. These findings indicate that pathogenic and non-pathogenic hantaviruses differentially regulate innate cellular defenses and suggest that the ability of pathogenic hantaviruses to alter endothelial cell responses is a fundamental determinant of hantavirus pathogenesis. Although there is no information about how hantavirus proteins might direct or regulate IFN responses, we recently identified hantavirus protein interactions that may influence IFN responses. Our preliminary results suggest that pathogenic hantavirus proteins play a role in blocking cellular defenses and thereby permit pathogenic hantaviruses to replicate within endothelial cells. Objective: We propose to investigate the differential regulation of endothelial cell responses by pathogenic and non-pathogenic hantaviruses. We will define hantavirus proteins that repress IFNb responses and determine the role of IRF-3 and NF-kB activation on hantavirus replication in order to define signaling pathways and proteins that are regulated by pathogenic hantaviruses. These experiments provide a fundamental understanding of hantavirus regulation of innate cellular defenses, define determinants of hantavirus pathogenesis and are anticipated to provide therapeutic targets for hantavirus disease interventions. Specific Aims: Aim 1) Define Hantavirus Proteins that Regulate Cellular IFN Responses. Aim 2) Evaluate Mechanisms of Signaling Pathway Regulation by Pathogenic Hantaviruses.