Early Response to Hemorrhagic Fever-Causing Arenaviruses

描述(由申请人提供)：我们的申请将解决诊断的需要，以确定感染了一种强毒出血热病毒，拉沙热病毒(LASV)。在进入人体的几个小时内，病原体就会从循环中的白细胞中引发反应。病原体改变细胞基因表达的能力可以通过分析细胞RNA来监测。我们的方法是将标准化的白细胞培养暴露于病原体，并在基因芯片上监测细胞mRNA表达的变化。对选定药物的初步研究显示，基因表达发生了几个病原体特有的变化。在这里，我们建议将我们的分析扩大到一种引起出血热的阿拉伯病毒--拉沙热病毒。我们将检验这样一个假设，即我们可以区分危险的引起出血热的病毒和不会导致疾病的密切相关的病毒。通过监测不同时间点的基因表达反应，我们将确定病原菌特异性基因表达信号出现的最早时间。这些基因表达的变化可以通过对人和猴子外周血单个核细胞(PBMC)的RNA分析来验证，并将作为暴露于危险病原体的诊断标志。将确定一组基因，将拉沙热病毒感染与相关无毒病毒感染区分开来，这些基因将被用于制造更小的微阵列，以进一步简化诊断。这样的诊断将消除在确定病原体之前等待症状或病原体复制的需要。这将使对生物恐怖袭击作出更适当和更迅速的反应成为可能。

DESCRIPTION (provided by applicant): Our application will address the need for diagnostics to identify infection with a virulent hemorrhagic fever virus, Lassa fever virus (LASV). Within hours of entering the body, pathogens elicit responses from circulating white blood cells. The pathogen's capacity to alter cellular gene expression can be monitored by analysis of cellular RNA. Our approach has been to expose a standardized culture of white blood cells to a pathogen and to monitor changes in cellular mRNA expression on gene microarrays. Preliminary studies with select agents revealed several pathogen-specific changes in gene expression. Here we propose to expand our analyses to a hemorrhagic fever-causing arenavirus, Lassa Fever virus. We will test the hypothesis that we can discriminate between a dangerous hemorrhagic fever-causing virus and closely related viruses that do not cause disease. By monitoring gene expression responses at different timepoints we will determine the earliest time at which pathogen-specific gene expression signals arise. These gene-expression changes can be validated by the analysis of RNA from human and monkey peripheral blood mononuclear cells (PBMCs), and will serve as diagnostic markers of exposure to dangerous pathogens. Sets of genes will be identified that discriminate infection with Lassa Fever virus from infection with a related avirulent arenavirus, and these genes will be used to make smaller microarrays to further streamline diagnosis. Such diagnostics would eliminate the need to wait for symptoms or for pathogen replication before identifying the pathogen. This would enable more appropriate and rapid responses to a bioterrorist attack.