High-throughput Screenings to Identify Host Receptors for Staphylococcal Adhesins

高通量筛选鉴定葡萄球菌粘附素宿主受体

基本信息

批准号：
8207921
负责人：
RENATA PASQUALINI
金额：
$ 8.43万
依托单位：
UNIVERSITY OF TX MD ANDERSON CAN CTR
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-01-01 至 2012-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8207921
关键词：
Adherence Adhesions Adhesives Affect Alternative Therapies American Animal Model Antibiotic Resistance Bacteria Bacterial Adhesins Binding Biology Blood Circulation Cell Surface Proteins Cell Wall Communicable Diseases Communities Comorbidity Cost-Benefit Analysis Data Disease Endocarditis Environment Epidemic Event Family Feasibility Studies Genus staphylococcus Gram-Positive Bacteria Healthcare Systems Hospitals Immunocompromised Host Immunomodulators Individual Infection Infectious Skin Diseases Invaded Lactococcus lactis Ligands Lower respiratory tract structure Mediating Medical Methodology Minor Molecular Organism Pathogenesis Pathology Pattern Phage Display Play Pneumonia Process Proteins Recombinants Research Role Screening procedure Sepsis Skin Tissue Soft Tissue Infections Staging Staphylococcal Infections Staphylococcus aureus Staphylococcus epidermidis Surface System Techniques Technology Tissues Toxin United States Vaccination Vaccines Virulence Factors Virulent Work base design disorder prevention drug development high throughput screening microbial mortality mutant novel pathogenic bacteria public health relevance receptor therapeutic target vaccine development

项目摘要

DESCRIPTION (provided by applicant): Staphylococci cause a wide spectrum of infectious diseases spanning from rather minor skin infections to serious conditions such as sepsis, pneumonia and endocarditis. Although Staphylococcus aureus is by far the most virulent of species, Staphylococcus epidermidis and Staphylococcus lugdunensis have also been found to cause severe infections mostly in immunocompromised individuals. In the past, highly virulent S. aureus strains were confined to the hospital environment mostly affecting immunocompromised patients or individuals with underlying co-morbidities. Unfortunately, similar strains have recently emerged in the community causing severe infections in otherwise healthy individuals. To a lesser extent and slightly different pathology, Staphylococcus epidermidis and Staphylococcus lugdunensis seem to follow the same pattern. Most of these strains have evolved to be resistant to antibiotics, which resulted in a worldwide epidemic and an enormous burden for the healthcare system. Therefore, the necessity of a vaccine or identification of novel or alternative therapies for the treatment of these infections has become an unmet and pressing medical need. Despite intense efforts, the molecular mechanism of staphylococcal infections is incompletely understood, but it seemingly involves a large number of virulence factors such as adhesins, toxins and immunomodulators. To date, adhesion to host tissues is considered the foremost stage of infection and plays a vital role in the survival of the invading organism. Most likely, the synthesis of toxins and immunomodulators plays a role later in the disease process and depends on the first step of infection. Hence, proteins responsible for adherence have long been recognized as targets for drug and vaccine development. In staphylococci, as well as other Gram-positive bacteria, adhesion to host tissues is mostly mediated by a family of cell-wall-anchored (CWA) proteins referred to us microbial surface components recognizing adhesive matrix molecules (MSCRAMMs). These proteins have been shown to a) mediate adherence to host proteins, b) participate in self-aggregation and c) modulate the biology of the ligand protein. Furthermore, MSCRAMMs have been shown to be virulence factors in animal models of infection since a mutant lacking all these molecules fails to cause disease. Vaccination with recombinant MSCRAMMs or inhibition of their functions resulted in significant protection against disease. Based on these observations, it is widely agreed that identification of ligands for MSCRAMMs would contribute to a better understanding of molecular events leading to infection and would help us design effective vaccine or targeted therapeutics for disease prevention and treatment. To that end, this proposed research aims to establish a high-throughput phage display methodology to identify ligands for MSCRAMMs. This work will also serve as a feasibility study to determine if this technique is suitable for large-scale ligand discovery for bacterial cell surface proteins. PUBLIC HEALTH RELEVANCE: Staphylococcus aureus is the leading cause of bloodstream, lower respiratory tract, skin and soft tissue infections in the United States with an annual mortality approaching 100,000 Americans lives. Our research aims to better understand staphylococcal infection and to set the grounds for targeted therapies against this disease.

描述（由申请人提供）：葡萄球菌引起多种传染病，从相当轻微的皮肤感染到败血症、肺炎和心内膜炎等严重疾病。尽管金黄色葡萄球菌是迄今为止毒性最强的物种，但表皮葡萄球菌和路邓葡萄球菌也被发现可引起严重感染，主要发生在免疫功能低下的个体中。过去，高毒力金黄色葡萄球菌菌株仅限于医院环境，主要影响免疫功能低下的患者或患有潜在共病的个体。不幸的是，最近社区中出现了类似的菌株，导致健康个体出现严重感染。表皮葡萄球菌和路邓葡萄球菌似乎遵循相同的模式，程度较小且病理学略有不同。这些菌株中的大多数已经进化到对抗生素具有抗药性，这导致了世界范围内的流行，并给医疗保健系统带来了巨大的负担。因此，用于治疗这些感染的疫苗或鉴定新的或替代疗法的必要性已成为未满足且紧迫的医疗需求。尽管付出了巨大的努力，葡萄球菌感染的分子机制仍不完全清楚，但它似乎涉及大量的毒力因子，如粘附素、毒素和免疫调节剂。迄今为止，与宿主组织的粘附被认为是感染的最重要阶段，并且在入侵生物体的生存中发挥着至关重要的作用。最有可能的是，毒素和免疫调节剂的合成在疾病过程的后期发挥作用，并且取决于感染的第一步。因此，负责粘附的蛋白质长期以来一直被认为是药物和疫苗开发的靶标。在葡萄球菌以及其他革兰氏阳性细菌中，对宿主组织的粘附主要是由细胞壁锚定 (CWA) 蛋白家族介导的，CWA 蛋白是指识别粘附基质分子的微生物表面成分 (MSCRAMM)。这些蛋白质已被证明 a) 介导对宿主蛋白质的粘附，b) 参与自我聚集，以及 c) 调节配体蛋白质的生物学特性。此外，MSCRAMM 已被证明是动物感染模型中的毒力因子，因为缺乏所有这些分子的突变体不会引起疾病。重组 MSCRAMM 疫苗接种或抑制其功能可显着预防疾病。基于这些观察结果，人们普遍认为，MSCRAMM 配体的鉴定将有助于更好地了解导致感染的分子事件，并有助于我们设计有效的疫苗或靶向疗法来预防和治疗疾病。为此，本研究旨在建立一种高通量噬菌体展示方法来识别 MSCRAMM 的配体。这项工作还将作为可行性研究，以确定该技术是否适用于细菌细胞表面蛋白的大规模配体发现。公共卫生相关性：金黄色葡萄球菌是美国血液、下呼吸道、皮肤和软组织感染的主要原因，每年导致近 100,000 名美国人死亡。我们的研究旨在更好地了解葡萄球菌感染，并为针对这种疾病的靶向治疗奠定基础。