Diagnosis and Pathobiology of Emerging Enterohepatic Helicobacter spp. in Mice

描述（由申请方提供）：我们很高兴有机会对NCRR RFA-RR-10-005“实验室动物新发病原体的病理学”做出回应。在过去的15年中，8个新的肠肝螺杆菌。(EHS)已经正式命名，并且在我们的实验室中已经培养和鉴定了9个新物种的额外簇（基于16 S rRNA序列）。我们已经收集了，我们认为，是世界上最大的EHS培养物收集，并准备表征这些鼠株，既方便他们的诊断，也建立他们的致病潜力。H. EHS的原型hepaticus引起持续的肠道感染，并且在全世界的学术小鼠群体中普遍存在。H.肝球菌感染引起肝癌，已知在几种肝癌发生模型中是强肿瘤促进剂，并在免疫受损小鼠中诱导炎性肠病。EHS的存在已经混淆了许多研究，可以污染肿瘤细胞系，导致免疫缺陷小鼠和选定的免疫活性小鼠品系的显著发病率和死亡率，并且最近与小鼠群体的生殖失败有关。我们在2007年进行的一项研究表明，全球学术环境中使用的小鼠中有85%感染了一种或多种EHS。然而，大多数EHS，我们和其他人已经确定，不容易培养，没有特定的分子或血清学检测诊断，也不知道是否和在什么条件下，这些H。spp.具有致病潜力。因此，我们打算开发敏感和特异性的分子检测来诊断小鼠EHS。我们期望开发一种微型微阵列芯片，供研究界用于检测EHS并防止其在已建立的H。spp.自由殖民地由于IL-10-/-在本实验室和其他人使用H. hepaticus来探讨IBD的发病机制，我们将利用该模型筛选新的H. spp.致病潜力以及确定毒力基因在新测序的H. spp.这些结果将与我们用于预测H.肝本项目的具体目标是：1）提供新的肠肝螺杆菌（EHS）的形态学、遗传学和生物化学特征，并开发种特异性检测方法来诊断从小鼠分离的EHS; 2）确定小鼠EHS的体外毒力因子与IL 10-/-细胞中的体内致病潜力的关系，小鼠模型，并确定宿主的免疫应答如何影响疾病进展;和3）鉴定和表征3种肠螺杆菌属的基因组序列中的毒力决定因子。分离自啮齿动物和患有临床疾病的人类，以及H.并确定这些基因在C57 BL IL 10-/-小鼠中诱导IBD中是否是可操作的。为了实现这些目标，我们组建了一个科学家团队，他们在过去十年中成功地合作研究了H。小鼠肝胃肠道疾病。

DESCRIPTION (provided by applicant): We are excited about the opportunity to respond to the NCRR RFA-RR-10-005 "Pathobiology of Emerging Pathogens in Laboratory Animals". During the past 15 years, 8 novel enterohepatic Helicobacter spp. (EHS) in mice have been formally named, and 9 additional clusters (based on 16S rRNA sequences) of novel species have been cultured and identified in our lab. We have collected, what we believe, is the largest EHS culture collection available worldwide and are poised to characterize these murine strains, both to facilitate their diagnosis and also to establish their pathogenic potential. H. hepaticus, the prototype EHS, causes a persistent enteric infection and is prevalent in academic mouse colonies throughout the world. H. hepaticus infection causes liver cancer, is known to be a strong tumor promoter in several models of hepatocarcinogenesis, and induces inflammatory bowel disease in immunocompromised mice. The presence of EHS has confounded a number of studies, can contaminate tumor cell lines, causes significant morbidity and mortality in immunodeficient mice and selected strains of immune-competent mice, and has been recently associated with reproductive failures in mouse colonies. A 2007 study conducted by us indicated that 85% of mice used in academic settings worldwide are infected with one or more EHS. However the majority of EHS, we and others have identified, are not easily cultured, do not have specific molecular or serological assays for diagnosis, nor is it known whether and under what conditions these H. spp. have pathogenic potential. We therefore intend to develop sensitive and specific molecular assays to diagnose EHS in mice. We anticipate the development of a mini-microarray chip for use by the research community to detect EHS and prevent their colonization in established H. spp. free colonies. Because of the utility of the IL10-/- in our lab and others in using H. hepaticus to dissect etiopathogenesis of IBD, we will employ this model in screening novel H. spp. for pathogenic potential as well as determine the putative role of virulence genes in newly sequenced H. spp. These results will be compared and validated with in vitro tests we have used to predict virulence potential in H. hepaticus. The specific aims of the project are: 1) To provide morphologic, genetic, and biochemical characterization of novel enterohepatic Helicobacter species (EHS) and develop species specific assays to diagnose EHS isolated from mice; 2) To define the relationship of in vitro virulence factors of murine EHS to in vivo pathogenic potential in the IL10-/- mouse model and to determine how the hosts' immune responses influence disease progression; and 3) To identify and characterize virulence determinants in the genome sequences of 3 enteric Helicobacter spp. isolated from rodents and humans with clinical disease, as well as those of H. hepaticus and determine if these genes are operable in inducing IBD in C57BL IL10-/- mice. To accomplish these aims we have assembled a team of scientists who have successfully collaborated together for the last decade to study the etiopathogenesis of H. hepaticus gastrointestinal disease in mice.