Determinants of H. influenzae Virulence in Otitis Media

中耳炎中流感嗜血杆菌毒力的决定因素

• 批准号: 7850050
• 负责人: Lauren O Bakaletz
• 金额: $ 23.22万
• 依托单位: RESEARCH INST NATIONWIDE CHILDREN'S HOSP
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-07-17 至 2011-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7850050
• 关键词: Acute; Adjuvant; Amino Acids; Animal Model; Animals; Antigens; Biological; Biological Assay; Biophotonics; Childhood; Chinchilla (genus); Chronic; Clinical; Complex; Data; Development; Diagnosis; Disease; Eustachian Tube; Evaluation; Facilities and Administrative Costs; Focus Groups; Funding; Gene Expression Profile; Gene Expression Profiling; Genes; Genome; Goals; Haemophilus influenza virulence; Haemophilus influenzae; Image; Immune response; Immunization; Immunobiology; In Situ; In Vitro; Incidence; Infection; Invaded; Investigation; Laboratories; Lead; Life; Mediating; Methodology; Methods; Microarray Analysis; Modeling; Molecular; Molecular Profiling; Monitor; Morbidity - disease rate; Mutagenesis; Nasopharynx; Nontypable Haemophilus influenza; Office Visits; Otitis Media; Otitis Media with Effusion; Outcome Measure; Pathogenesis; Phase; Positioning Attribute; Prevention; Process; Relative (related person); Research Personnel; Resources; Role; Route; Series; Staging; System; Time; Tympanic cavity; Upper respiratory tract; Vaccines; Virulence; Virus; adenylate; antimicrobial; base; cost; design; dosage; ear infection; experience; human disease; improved; in vivo; interest; middle ear; mortality; mutant; novel; parent grant; pathogen; plasmid DNA; pre-clinical; prevent; promoter; protective efficacy; research study; response; socioeconomics; superinfection; therapeutic target; vaccine candidate; vaccine development

DESCRIPTION (provided by applicant): Middle ear infection or otitis media (OM) is a highly prevalent pediatric disease worldwide. There were nearly twenty-five million physician's office visits made for OM in 1990, and available evidence suggests that the incidence is increasing. While only very rarely associated with mortality, the morbidity associated with OM is significant. The socioeconomic impact of OM is also great. Direct and indirect costs of diagnosing and managing OM exceed $5 billion annually in the U.S. alone. Clearly, there is a tremendous need to develop more effective and accepted approaches to the management and preferably, the prevention of OM. Vaccine development holds the greatest promise and would be the most cost-effective method to accomplish this goal. However, progress in terms of vaccine development for nontypeable Haemophilus influenzae (NTHI), the Gram-negative pathogen that both predominates in chronic otitis media with effusion or OME, as well as being a significant etiologic agent of acute OM, continues to be hampered by our incomplete understanding of the pathogenesis and immunobiology ofOM, a polymicrobial disease caused by one or more of the three predominant bacterial pathogens, whose ability to invade the tympanum is facilitated by virtually any upper respiratory tract (URT) virus. During the past 4 years, we have: sequenced and will soon complete the annotation of the genome of an OM isolate of nontypeable Haemophilus influenzae (NTHI); developed and used DNA plasmid based microarrays to conduct strain comparison studies for two clinical OM isolates; developed a promoter trap system in NTHI with which we have monitored gene expression in vivo, during experimental OM; and have developed a signature tag mutagenesis system in NTHI that provided us with a complementary system to identify genes that are essential for colonization and induction of OM. Not only are all these tremendous resources available to us to capitalize upon as we extend our studies of the pathogenesis of NTHI-induced OM, but they have also already resulted in the identification of multiple potential new virulence determinants for NTHI. We propose experiments for the next funding period designed to continue to enhance our understanding of both NTHI pathogenesis in OM at the molecular level as well as further our investigation of a focused group of novel virulence determinants. We will first rigorously assess the feasibility of using lux-expressing NTHI strain 86-028NP to provide a non-invasive, whole animal imaging system to be applied to, and significantly advance, our studies of both pathogenesis and vaccine-mediated prevention of OM. Secondly, we will use a chinchilla super infection model to assess the protective efficacy of one well-developed candidate antigen and one novel and highly promising, but less developed candidate, for ability to prevent ascending OM after intranasal immunization. We will also continue to identify and characterize putative virulence determinants and assess their potential as vaccine or therapeutic targets via a variety of methodologies, including gene expression profiling by microarray analysis. Overall, our studies will lead to an improved understanding of OM caused by NTHI and lead to new strategies to prevent OM.

描述（由申请人提供）：中耳感染或中耳炎（OM）是全球高度普遍的小儿疾病。 1990年，有近2500万医师的办公室就诊，可用的证据表明发病率正在增加。虽然很少与死亡率相关，但与OM相关的发病率很重要。 OM的社会经济影响也很大。仅在美国，诊断和管理OM的直接和间接成本超过50亿美元。显然，巨大的需求需要开发更有效和公认的管理方法，最好是预防OM。疫苗开发是最大的希望，将是实现这一目标的最具成本效益的方法。然而，在疫苗发育的进展方面进展不可抑制嗜血性流感（NTHI），这两者在慢性耳鼻炎培养基中均占主导地位，这些病原体在慢性耳炎培养基中占主导地位或OME的重要病因，并且是对急性OM的重要病因学因素，它会因我们对经济学疾病的不良疾病而受到一定的理解，并受到较大的理解，即一种疾病的疾病，即一种或免疫学的疾病，一种或免疫生物学的疾病，是一种或免疫生物学作用。主要的细菌病原体，其侵入鼓膜的能力几乎由任何上呼吸道（URT）病毒促进。 在过去的四年中，我们已经进行了：测序并将很快完成对不可能流感嗜血杆菌的OM分离株的注释（NTHI）；开发和使用基于DNA质粒的微阵列进行两种临床OM分离株进行菌株比较研究。在实验OM期间，在NTHI中开发了一个启动子陷阱系统，我们在体内监测了基因表达。并在NTHI中开发了一个签名的TAG诱变系统，该系统为我们提供了一个补充系统，以识别对OM定植和诱导至关重要的基因。当我们扩展对NTHI诱导的OM的发病机理的研究时，我们不仅可以利用所有这些巨大的资源来利用，而且它们也已经导致了NTHI的多种潜在的新毒力决定因素的鉴定。 我们建议在下一个融资期间进行实验，旨在继续增强我们对分子水平OM中NTHI发病机理的理解，并进一步研究集中的新型毒力决定因素。首先，我们将严格评估使用表达Lux的NTHI菌株86-028NP的可行性，以提供一种无创的，全动物成像系统，可用于应用于我们对发病机理和疫苗介导的OM预防的研究。其次，我们将使用龙猫超级感染模型来评估一种发达的候选抗原和一种新颖且高度有前途但发达的候选者的保护作用，以防止鼻内免疫后升高OM。我们还将继续识别和表征推定的毒力决定因素，并通过多种方法评估其作为疫苗或治疗靶标的潜力，包括通过微阵列分析进行基因表达分析。 总体而言，我们的研究将导致对NTHI引起的OM的了解，并导致预防OM的新策略。