P. aeruginosa type III secreted effectors in corneal disease

角膜疾病中铜绿假单胞菌 III 型分泌效应子

基本信息

批准号：
8597435
负责人：
Arne Rietsch
金额：
$ 38.47万
依托单位：
CASE WESTERN RESERVE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-01-01 至 2015-07-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8597435
关键词：
ADP Ribose Transferases Acute Address Animal Model Bacteria Blindness Cells Complement Contact Lenses Cornea Corneal Diseases Corneal Stroma Data Development Disease Disease Progression Dose Enzymes Epithelial Cells Extended-Wear Contact Lenses Eye Infections Eye Injuries Genome Grant Immune Immune response Immune system Individual Infection Infection prevention Invaded Keratitis Lead Left Link Lung Mediating Modeling Molecular Mus Neutrophil Infiltration Organism Pathogenesis Patients Peptide Hydrolases Phenotype Phospholipase Pilum Positioning Attribute Production Properdin Proteins Pseudomonas aeruginosa Reporting Research Role Severity of illness Shapes Signal Transduction Site Staging Syringes TLR4 gene TLR5 gene Toll-like receptors Type III Secretion System Pathway Virulence Virulence Factors Visual impairment bacterial genetics chemokine combat corneal epithelium cytotoxic design extracellular in vivo killings macrophage microbial neutrophil prevent research study rho uptake

项目摘要

P. aeruginosa infections are a common cause of corneal disease associated with extended-wear contact lens use here in the US. One of the primary virulence factors P. aeruginosa uses to promote disease is its type III secretion system, a molecular syringe that allows the bacterium to directly inject effector proteins into targeted host cells. The role of type III secretion in corneal disease has not been studied extensively, but initial reports suggest that corneal disease depends on the complement of effectors being expressed by the infecting bacteria. "Cytotoxic" strains expressing the potent phospholipase ExoU rely extensively on type III secretion to promote disease, whereas ExoS-producing "invasive" strains, appear to not rely on type III secretion in order to elicit corneal disease. We have revisited the role of type III secretion in the pathogenesis of corneal disease elicited by ExoS+ "invasive" isolates of P. aeruginosa. Our preliminary data demonstrates that corneal disease relies critically on type III secretion and on the two effectors ExoS and ExoT, in particular. In addition, we provide evidence that the primary role of type III secretion in corneal disease is to stave off killing by infiltrating neutrophils. Accordingly, the focus of this proposal is to determine the role of the individual enzymatic activities of ExoS and ExoT in preventing clearance by neutrophils in vivo. We will correlate these findings with experiments aimed at examining the role of ExoS and ExoT in preventing phagocytic killing by isolated primary neutrophils. We will also examine the difference in pathogenesis between ExoU-expressing "cytotoxic" and ExoS- expressing "invasive" strains of P. aeruginosa in order to determine if any differences can be directly linked to the activities of these two effectors. Understanding the role of effector proteins in corneal disease is an important step towards formulating new strategies for preventing and treating P. aeruginosa infections of the eye.

铜绿假单胞菌感染是与长时间佩戴相关的角膜疾病的常见原因在美国使用隐形眼镜。铜绿假单胞菌用来促进疾病的主要毒力因子之一是它的III型分泌系统是一种分子注射器，可以让细菌直接注射效应蛋白进入目标宿主细胞。 III 型分泌物在角膜疾病中的作用尚未得到广泛研究，但初步报告表明，角膜疾病取决于角膜表达的效应器的补充。感染细菌。表达强效磷脂酶 ExoU 的“细胞毒性”菌株广泛依赖于 III 型分泌促进疾病，而产生 ExoS 的“侵入性”菌株似乎不依赖 III 型分泌物以引起角膜疾病。我们重新审视了 III 型分泌物在 ExoS+ 引起的角膜疾病发病机制中的作用铜绿假单胞菌的“侵入性”分离株。我们的初步数据表明，角膜疾病主要依赖于 III 型分泌，特别是对两个效应器 ExoS 和 ExoT 的影响。此外，我们提供证据表明 III 型分泌物在角膜疾病中的主要作用是避免浸润性中性粒细胞造成的杀伤。因此，本提案的重点是确定 ExoS 各个酶活性的作用 ExoT 可以防止体内中性粒细胞的清除。我们将把这些发现与实验联系起来旨在研究 ExoS 和 ExoT 在防止分离的初级中性粒细胞吞噬细胞杀伤中的作用。我们还将检查表达“细胞毒性”的 ExoU 和表达“细胞毒性”的 ExoS 之间发病机制的差异。表达铜绿假单胞菌的“侵入性”菌株，以确定是否有任何差异可以直接与这两个效应器的活动。了解效应蛋白在角膜疾病中的作用是制定治疗方案的重要一步预防和治疗眼部铜绿假单胞菌感染的新策略。