HOST-PATHOGEN GENE EXPRESSION DURING A PULMONARY MYCOBAC

结核分枝杆菌(Mtb)对免疫功能低下和免疫功能正常的人群都是一个重大威胁。结核分枝杆菌是一种细胞内生物体，具有极其复杂的生命周期，包括对正常宿主防御机制的抵抗和随后的潜伏状态的发展。同样，宿主对结核分枝杆菌感染的反应是一系列复杂的免疫事件，导致肉芽肿性炎症来控制结核分枝杆菌的增殖，随后形成肉芽肿，使结核分枝杆菌处于潜伏状态。耐药结核分枝杆菌菌株的发展使了解其发病机制成为高度优先事项，以便确定抗生素和免疫调节干预的潜在靶点。最近对结核分枝杆菌基因组的测序为帮助解剖结核分枝杆菌的发病机制提供了一个令人兴奋的数据库。随着微阵列技术在体内感染中的应用，有可能分析感染不同阶段的全基因组表达。我们假设，在宿主和结核分枝杆菌之间的动态相互作用过程中，环境会发生一系列变化，导致基因的差异表达，从而提高宿主和结核分枝杆菌的存活率。我们打算使用微阵列分析来确定在小鼠肺部感染结核分枝杆菌期间发生的基因表达。我们将使用包含结核分枝杆菌基因组所有开放阅读框架的阵列，以及包含大约100个免疫应答小鼠基因的阵列。这将使我们能够关联宿主的变化，从而导致有机体的变化。最后，我们将使用基于体内荧光素酶的技术来实时跟踪结核分枝杆菌感染和基因表达。这一模型的开发将提供一个高通量的系统，用于测试治疗干预措施，使用比标准测试更少的小鼠，并显著增强我们监测体内特定Mtb基因表达的能力。

Mycobacterium tuberculosis (Mtb) is a significant threat to both immunocompromised and immunocompetent populations. Mtb is an intracellular organism with an extremely complicated life cycle involving resistance to normal host defense mechanisms and subsequent development of a latent state. Similarly, the host response to Mtb infection is a complex series of immune events resulting in granulomatous inflammation to control Mtb proliferation with subsequent formation of granulomas that maintain Mtb in a latent state. The development of drug resistant Mtb strains has made the understanding of its pathogenesis a high priority in order to identify potential targets for antibiotics and immunomodulatory interventions. The recent sequencing of the Mtb genome has provided an exciting database for aiding in dissecting Mtb pathogenesis. Together with the application of microarray technology to in vivo infections, there is the potential for an analysis of genome wide expression during different stages of infection. We hypothesize that during the dynamic interactions between the host and the Mtb there is a series of changes in the environment that lead to differential expression of genes that enhance survival for both the host and the Mtb. We intend to use microarray analysis to determine the gene expression that occurs during a pulmonary infection with Mtb in the mouse. We will use arrays that contain all open reading frames of the Mtb genome as well as an array containing approximately 100 immunoresponsive murine genes. This will allow us to correlate changes in the host that result in changes in the organism. Finally, we will use an in vivo luciferase based technology to track Mtb infections and gene expression in real time. The development of this model will provide a high through put system for testing therapeutic interventions using fewer mice than standard assays as well as significantly enhance our ability to monitor specific Mtb gene expression in vivo.