Redefining the role of autophagy in bacterial disease

重新定义自噬在细菌性疾病中的作用

基本信息

批准号：
10053295
负责人：
Ken Hashigiwa Cadwell
金额：
$ 51.51万
依托单位：
NEW YORK UNIVERSITY SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-11-10 至 2021-10-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10053295
关键词：
Adverse effects Antibiotic Resistance Antibiotics Antimicrobial Resistance Attention Autophagocytosis Bacteria Bacterial Infections Cell Culture Techniques Cell membrane Cell surface Cells Childhood Clinical Communicable Diseases Communities Cytosol Data Defense Mechanisms Development Disease Drug Targeting Drug usage Endothelium Epithelial Genes Goals Health Host Defense Human Immune In Vitro Infection Inflammasome Integration Host Factors Knockout Mice Literature Lysosomes Mediating Mediation Membrane Membrane Proteins Modeling Morbidity - disease rate Multiple Bacterial Drug Resistance Mus Mutant Strains Mice Natural Resistance Outcome Pathway interactions Phagosomes Pharmacology Physiological Pneumonia Process Proteome Publications Recycling Regulation Resistance Resistance to infection Role Salmonella Salmonella infections Salmonella typhimurium Sepsis Signal Transduction Specificity Staphylococcus aureus Staphylococcus aureus infection Streptomycin Testing Therapeutic Tissues Toxin Vacuole Vesicle Virulent alpha Toxin antimicrobial bacterial resistance cell injury cell type enteric infection experimental study improved in vivo inhibition of autophagy inhibitor/antagonist interest methicillin resistant Staphylococcus aureus microbicide mortality mutant novel pathogen pathogenic bacteria prevent prophylactic receptor recruit repaired resistant strain sensor

项目摘要

PROJECT SUMMARY In addition to traditional antimicrobials, targeting host defense pathways is an attractive strategy to limit the adverse effect of bacterial infection. One such pathway that has received considerable attention is autophagy, a process by which cellular constituents are sequestered in a double-membrane vesicle that is subsequently targeted to the lysosome for degradation and recycling. Autophagy is suggested to be critical for cell autonomous defense because many bacterial pathogens are detected within double-membrane vesicles upon internalization. Therefore, it is possible that drugs that target autophagy will be useful in a wide range of diseases downstream of bacterial infections. However, in addition to a direct microbicidal mechanism, autophagy has many substrates and cell type-specific functions that may contribute to the outcome of an infection. Thus, we chose to re-examine the role of autophagy in vivo using two model pathogens – Salmonella enterica Typhimurium and Staphylococcus aureus. We chose to investigate S. Typhimurium because previous in vitro studies extensively demonstrated that this bacterium is targeted for degradation through autophagy. In contrast, in vitro experiments indicate that S. aureus uses the autophagy machinery for intracellular survival. In preliminary data, we demonstrate that inhibiting autophagy in vivo leads to the opposite outcome that is predicted by the literature. Specifically, autophagy mutants were protected from S. Typhimurium and susceptible to S. aureus. The goal of this proposal is to elucidate the physiological mechanism by which autophagy functions during infection by these two important bacterial pathogens. In Aim 1, we will test a model in which S. Typhimurium recruits the autophagy machinery to repair the Salmonella-containing vacuole (SCV) and evade innate immune sensors. In Aim 2, we will define a novel role for autophagy in regulating the cell surface proteome of the host cells, a function that is critical in limiting damage caused by a pore-forming toxin produced by S. aureus. The results from the proposed experiments will challenge the existing paradigm on the role of autophagy in antimicrobial defense and guide the proper use of drugs that target autophagy.

项目概要除了传统的抗菌药物外，针对宿主防御途径是限制细菌感染的一种有吸引力的策略。细菌感染的不利影响之一是自噬，受到广泛关注。细胞成分被隔离在双膜囊泡中的过程，随后针对溶酶体的降解和回收被认为对细胞至关重要。自主防御，因为许多细菌病原体在双膜囊泡内被检测到因此，靶向自噬的药物可能会有广泛的用途。然而，除了直接的杀菌机制之外，自噬具有许多底物和细胞类型特异性功能，可能有助于自噬的结果因此，我们选择使用两种模型病原体——沙门氏菌来重新研究自噬在体内的作用。我们选择研究鼠伤寒沙门氏菌是因为之前的研究。体外研究主要证明该细菌是通过自噬降解的。相反，体外实验表明金黄色葡萄球菌利用自噬机制实现细胞内存活。初步数据表明，抑制体内自噬会导致相反的结果，即具体来说，自噬突变体受到保护，免受鼠伤寒沙门氏菌和鼠伤寒沙门氏菌的侵害。该提案的目的是阐明其生理机制。在这两种重要的细菌病原体感染期间，自噬发挥作用。在目标 1 中，我们将测试一个模型。其中鼠伤寒沙门氏菌招募自噬机制来修复含有沙门氏菌的真空（SCV）在目标 2 中，我们将定义自噬在调节细胞中的新作用。宿主细胞的表面蛋白质组，这种功能对于限制成孔毒素造成的损伤至关重要由金黄色葡萄球菌产生的实验结果将挑战现有的范式。自噬在抗菌防御中的作用并指导正确使用针对自噬的药物。