H. influenzae Genes Associated with Acute Otitis Media

与急性中耳炎相关的流感嗜血杆菌基因

• 批准号: 6661988
• 负责人: JANET R GILSDORF
• 金额: $ 37.68万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-20 至 2007-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6661988
• 关键词: DNA; Haemophilus influenzae; bacterial genetics; beta lactamase; children; clinical research; genetic screening; genetic strain; genotype; host organism interaction; human data; microarray technology; middle ear; molecular cloning; nasopharynx; nucleic acid sequence; otitis media; pulsed field gel electrophoresis; subtraction hybridization; virulence

DESCRIPTION (provided by applicant): Acute otitis media results from a complex interplay of host defenses, environmental factors, and virulence characteristics of bacteria. Previous studies suggest that Haemophilus influenzae (Hi), an important cause of acute otitis media in children, possess unique genes important in the pathogenesis of this infection. In this project, we will identify potential virulence factors specific for Hi otitis media. Using a subtractive hybridization technique, we will identify DNA fragments present in Hi otitis media isolates and absent in Hi throat isolates. The subtracted DNA fragments will be cloned, sequenced and used to determine their prevalence among large panels of Hi strains grouped by various epidemiologic parameters. Our large collection of Hi strains will be screened for the otitis media associated genes using a gene detection-based microarray consisting of genomes of the Hi strains and associations among these genes as well as between these genes and epidemiologic factors established. The Specific Aims of this project are: 1. Characterize Hi isolated from middle ear effusions of children with acute otitis media and from nasopharyngeal throat specimens of children by biotype, serotype, b-lactamase production and genotype by pulsed field gel electrophoresis. 2. Identify candidate Hi otitis media associated genes through subtractive hybridization. 3. Describe associations among candidate Hi otitis media associated genes and between Hi otitis media associated genes and epidemiologic parameters, including site of isolation, geographic location, persistence of nasopharyngeal colonization and ability to be transmitted child to child, using a microarray of Hi genomic DNA from each strain in our collections. 4. Characterize the Hi otitis media associated genes by size, predicted function, and location in the Hi chromosome. Identification of unique Hi otitis media virulence factors will facilitate the development of novel approaches to the prevention and treatment of Hi otitis media.

描述（由申请人提供）：急性中耳炎是由宿主防御、环境因素和细菌毒力特征的复杂相互作用引起的。先前的研究表明，流感嗜血杆菌（Hi）是儿童急性中耳炎的重要病因，其独特的基因在这种感染的发病机制中发挥着重要作用。在这个项目中，我们将确定 Hi 中耳炎特有的潜在毒力因子。使用消减杂交技术，我们将鉴定 Hi 中耳炎分离株中存在而 Hi 咽喉分离株中不存在的 DNA 片段。减去的 DNA 片段将被克隆、测序并用于确定其在按各种流行病学参数分组的大量 Hi 毒株中的流行情况。我们将使用基于基因检测的微阵列来筛选我们大量的 Hi 菌株中的中耳炎相关基因，该微阵列由 Hi 菌株的基因组和这些基因之间以及这些基因与已建立的流行病学因素之间的关联组成。该项目的具体目标是： 1.通过脉冲场凝胶电泳对从患有急性中耳炎的儿童的中耳积液和儿童的鼻咽喉标本中分离出的Hi进行生物型、血清型、β-内酰胺酶的产生和基因型的表征。 2.通过消减杂交鉴定候选Hi中耳炎相关基因。 3. 使用我们收集的每个菌株的 Hi 基因组 DNA 微阵列，描述候选 Hi 中耳炎相关基因之间以及 Hi 中耳炎相关基因与流行病学参数之间的关联，包括分离地点、地理位置、鼻咽定植的持续性和儿童传播的能力。 4. 通过 Hi 染色体的大小、预测功能和位置来表征 Hi 中耳炎相关基因。 独特的 Hi 中耳炎毒力因子的鉴定将有助于开发预防和治疗 Hi 中耳炎的新方法。