Detection of M. paratuberulosis in Crohn's Disease

克罗恩病中副结核分枝杆菌的检测

• 批准号: 8624341
• 负责人: Vivek Kapur
• 金额: $ 21.11万
• 依托单位: PENNSYLVANIA STATE UNIVERSITY, THE
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8624341
• 关键词: Address; Animals; Antibodies; Biological Assay; Blinded; Cattle; Characteristics; Chronic; Clinical; Clinical Sensitivity; Collaborations; Collection; Commit; Crohn' s disease; Detection; Development; Diagnosis; Diagnostic; Diagnostic tests; Disease; Epidemiology; Food Supply; Formalin; Future; Gastrointestinal tract structure; Genetic; Genome; Genus Mycobacterium; Goals; Histologic; Human; Human Milk; Immunohistochemistry; Individual; Infection; Inflammatory; Inflammatory Bowel Diseases; Intestinal Diseases; Intestines; Investigation; Letters; Manure; Milk; Molecular; Monoclonal Antibodies; Mus; Mycobacterium Infections; Mycobacterium avium; Mycobacterium tuberculosis; Organism; Paraffin Embedding; Paratuberculosis; Pathogenesis; Patients; Performance; Play; Predisposition; Prevalence; Public Health; Recombinant DNA; Reproducibility; Resources; Role; Ruminants; Sampling; Sensitivity and Specificity; Specificity; Testing; Time; Tissue Sample; Tissues; animal tissue; base; enteritis; genome wide association study; human tissue; meetings; mycobacterial; pathogen; prevent; public health relevance; tissue fixing; tool; trend

Project Summary Crohn's disease (CD) is a chronic inflammatory disorder of the gastrointestinal tract, and there is strong evidence of considerable overlap between susceptibility loci for CD and mycobacterial infections. Increasing trends of CD are observed worldwide, and it is estimated that there are 400,000-600,000 patients with CD in the US. A clinically and histopathologically similar disease in ruminants, called Johne's disease (JD), is caused by Mycobacterium avium subspecies paratuberculosis (MAP). However, although long hypothesized, the association between MAP and CD remains unproven. This is, in large part, because of a lack of sensitive and specific diagnostic tests that are robust and can be easily applied to screen a sufficiently large number of tissue or clinical samples. After many years of effort, preliminary studies have finally led to the development of a monoclonal antibody (17A12) that specifically recognizes MAP. Hence, we here propose exploratory studies to meet the well-recognized need to develop highly specific and sensitive assays to detect MAP in tissues from CD patients. Two specific aims are proposed. In Aim 1, we will develop and establish performance characteristics of an immunohistochemistry (IHC) assay for the detection of MAP in tissues using the MAP-specific monoclonal antibody, 17A12. The IHC assay will be developed, standardized and validated on a collection of paraffin embedded tissue samples from animals with pluribacillary or pauciacillary infections, and from mice experimentally inoculated with other mycobacteria (M. avium and M. tuberculosis). Performance characteristics such as analytical sensitivity, specificity, precision (repeatability and reproducibility), and accuracy of the newly developed assay will be determined. In Aim 2, we will apply the newly developed IHC assay as a preliminary screen to test intestinal tissue from a convenience sample of CD patients and healthy controls for the presence of MAP and establish initial estimates of analytical and clinical sensitivity and specificity of the newly developed assay. Together, these studies will provide us with a long-needed robust toolkit to specifically detect MAP in tissues from patients with CD, and enable future large scale epidemiologic and mechanistic investigations that can address the association of MAP with CD. In the long-term, the availability of this highly specific and sensitive assay may have important clinical implications for the treatment of CD by enabling the identification of individuals that may benefit from targeted anti- mycobacterial therapy, as well as stimulate the development of control strategies to prevent the contamination of milk and the human food supply with MAP.

项目摘要 克罗恩病(CD)是一种慢性胃肠道炎症性疾病，有很强的 有证据表明CD和分枝杆菌感染的易感基因有相当大的重叠。渐增 全世界都在观察CD的发展趋势，据估计，全世界有40-60万CD患者 美国。反刍动物的一种临床和组织病理学相似的疾病，称为约翰氏病(JD)，是 由禽分支杆菌亚种副结核(MAP)引起。然而，尽管长期以来一直在假设， MAP和CD之间的联系仍未得到证实。这在很大程度上是因为缺乏敏感度 和特定的诊断测试，这些测试是可靠的，可以很容易地应用于筛查足够多的 组织或临床样本。经过多年的努力，初步研究终于导致了 一种能识别MAP的单抗(17A12)。因此，我们在这里建议进行探索性研究。 为了满足公认的需要，开发高特异性和高灵敏度的分析方法来检测组织中的MAP CD患者。提出了两个具体目标。在目标1中，我们将制定和建立绩效 免疫组织化学(IHC)法检测组织中MAP的特点 MAP特异性单抗17A12。将开发、标准化和验证IHC检测方法 在收集来自患有多菌体或少菌体感染的动物的石蜡包埋组织样本时， 以及实验中接种了其他分枝杆菌(禽分枝杆菌和结核分枝杆菌)的小鼠。 性能特征，如分析灵敏度、特异度、精密度(重复性和 重复性)，以及新开发的化验的准确性将被确定。在目标2中，我们将应用 新开发的IHC法作为一种从方便的样品中检测肠道组织的初步筛选 对CD患者和健康对照的MAP的存在进行初步估计并建立分析 以及新开发的检测方法的临床敏感性和特异性。总之，这些研究将为我们提供 使用长期需要的强大工具包来专门检测CD患者组织中的MAP，并使未来 可解决MAP与CD关联的大规模流行病学和机械性调查。在……里面 从长远来看，这种高度特异和敏感的检测方法的可用性可能具有重要的临床意义。 用于CD的治疗，通过识别可能受益于有针对性的抗病毒药物的个人 分枝杆菌治疗，以及刺激制定控制策略，以防止污染 牛奶和人类食物供应的MAP。