Detection of Host Response In Clostridium Difficile Infection

艰难梭菌感染中宿主反应的检测

• 批准号: 8859073
• 负责人: Jian-Ping Jin
• 金额: $ 24.4万
• 依托单位: NORTHSHORE UNIVERSITY HEALTHSYSTEM
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-07-01 至 2017-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8859073
• 关键词: Anaerobic Bacteria; Antibiotics; Antibodies; Archives; Biological Assay; Biological Markers; Campylobacter; Cessation of life; Clinical; Clinical Microbiology; Clostridium difficile; Colitis; Communicable Diseases; Communities; Community-Acquired Infections; Cytoskeleton; Data; Detection; Development; Diagnosis; Diagnostic; Diagnostic tests; Diarrhea; Disease; Enteral; Epithelial; Epithelial Cells; Escherichia coli; Etiology; Evaluation; Feces; Food; Generations; Goals; Gold; Health Care Costs; Health care facility; Healthcare; Hospital Costs; Hospitals; Immune response; Immunocompromised Host; Incidence; Individual; Infection; Inflammatory Bowel Diseases; Intestines; Laboratories; Large Intestine; Lead; Measures; Methodology; Methods; Morbidity - disease rate; Muscle; Organism; Parasites; Patient Care; Patients; Proteins; Protocols documentation; Pseudomembranous Colitis; Records; Recovery; Reproduction spores; Research; Research Project Grants; Salmonella; Sampling; Series; Shigella; Signs and Symptoms; Specificity; Specimen; Symptoms; Testing; Toxic Megacolon; Toxin; Tropomyosin; Uncertainty; Universities; Virulent; base; clinically significant; cost; design; enteric pathogen; high risk; improved; industry partner; mortality; next generation; novel; novel diagnostics; pathogen; patient population; protocol development; prototype; public health relevance; research clinical testing; response marker

 DESCRIPTION (provided by applicant): The aim of this research application is to develop a paradigm shift in diagnostic testing for a globally important, yet poorly diagnosed, healthcare-associated infectious disease, namely Clostridium difficile infection (CDI). CDI results from infection of the bowel by C. difficile, a Gram-positive, spore-forming, obligate anaerobic bacterium. It can cause (diarrheal) illness ranging from moderate diarrhea to severe colitis (toxic megacolon) with a high risk of death. For the last two decades CDI has re-emerged in healthcare facilities with nearly a 10- fold increase in mortality and significant excess healthcar cost. Current CDI diagnostics is limited to detection of the organism and/or its toxin product(s) i conjunction with clinical symptoms, and does not differentiate infected from simply colonized patients, thus leading to inaccurate diagnosis as well as antibiotic mis/overuse. To overcome these limitations and resolve uncertainty of CDI diagnosis, a ground-breaking concept for CDI diagnosis will be developed and evaluated during this research project. The project rationale is that C. difficile toxin B mechanism of action causes cytoskeletal disruption of colonic epithelial cells with release of non- muscle tropomyosin (Tm). Our hypothesis is that increased levels of Tm, a major protein in colonic epithelial cytoskeleton, in the patient's stool indicates a specific host response to CDI and can be used as a diagnostic target signifying active infection from C. difficile. The application objective is to develop and evaluate Tm detection in stool specimens as a biomarker for clinically significant manifestations of CDI. To accomplish it, we will pursue two specific aims: 1) Determine the feasibility of clinically appropriate fecal Tm detection. This aim will be accomplished by performing multiple tasks - generation of Tm specific antibodies, optimization of Tm recovery method from stool specimens, Tm detection protocol development and optimization utilizing controls mimicking CDI negative and positive specimens, and testing for potential interferences. 2) Evaluate fecal Tm as a CDI specific host response marker on specimens obtained from clinically diverse patient populations. For that, CDI positive and negative clinical specimens will be utilized for Tm detection and data comparison to clinical and microbiological records of the same specimens. The records are available due to access and use of remnant samples from the clinical microbiology laboratory. The specificity of CDI diagnostics will be validated on stool specimens from patients with diarrhea due to other enteric bacterial pathogens (E. coli, Salmonella, Shigella spp, and Campylobacter), parasites, antibiotic-associated diarrhea (not due to infection), and bowel disorders like inflammatory bowel disease. This proposed concept has great potential to allow development of a novel diagnostic application for CDI. It will serve as an example for the next generation of infectious disease diagnostics measuring host response instead of detecting pathogens or their products. Our long term goal is to improve patient care by delivering a host response CDI test ready for development with an industry partner, such as TechLab(r), Inc., as a commercial assay that can undergo FDA clearance trials.

 描述（应用程序提供）：本研究申请的目的是为全球重要但诊断较差的医疗保健相关感染疾病（即艰难梭菌感染（CDI））进行诊断测试的范式转移。 CDI results from infection of the bowel by C. difficile, a Gram-positive, sporre-forming, obligate anaerobic bacteria.它可能引起（腹泻）疾病，从中度腹泻到严重结肠炎（有毒 巨型）具有高死亡风险。在过去的二十年中，CDI已重新出现在医疗机构中，死亡率增加了几乎10倍，大量超过医疗费用。当前的CDI诊断仅限于检测生物体和/或其毒素产物与临床症状的整合，并且不会将感染与简单定植的患者区分开，从而导致不准确的诊断症以及抗生素错误/过度使用。为了克服这些局限性并解决CDI诊断的不确定性，将在此研究项目中开发和评估CDI诊断的开创性概念。该项目的理由是，艰难梭菌毒素B作用机理会导致结肠上皮细胞的细胞骨架破坏，并释放非肌肉肌动蛋白（TM）。我们的假设是，TM的水平增加，TM的水平是结肠上皮细胞骨架中的主要蛋白 宿主对CDI的反应，可以用作诊断目标，象征着艰难梭菌的主动感染。应用目标是开发和评估粪便物种中的TM检测，作为CDI临床显着表现的生物标志物。为了实现这一目标，我们将追求两个具体的目标：1）确定临床适当的粪便TM检测的可行性。该目标将通过执行多个任务来实现 - TM特定抗体的生成，从粪便样本中优化TM恢复方法，使用模仿CDI负面标本的控件的TM检测协议开发和优化，以及对潜在接口的测试。 2）评估粪便TM作为CDI特异性宿主反应标记，对从临床多样化的患者人群获得的标本中评估。为此，将使用CDI阳性和阴性临床标本用于TM检测，并将数据与同一标本的临床和微生物记录进行比较。这些记录是由于临床微生物实验室的残留样品的访问和使用而获得的。由于其他肠道细菌病原体（大肠杆菌，沙门氏菌，志贺氏菌和弯曲杆菌），寄生虫，抗生素相关的腹泻（不引起感染）以及炎症性疾病性弓形病。这个提出的概念具有巨大的潜力，可以允许开发新的CDI诊断应用。它将作为测量宿主反应的下一代传染病诊断，而不是检测病原体或其产品的一个例子。我们的长期目标是通过提供与行业合作伙伴（例如TechLab（R），Inc。）的宿主响应CDI测试来改善患者护理，作为可以接受FDA清算试验的商业测定法。