Molecular dissection of Pseudomonas aeruginosa Exotoxin T virulence functions

铜绿假单胞菌外毒素T毒力功能的分子解析

基本信息

批准号：
9052701
负责人：
SASHA H SHAFIKHANI
金额：
$ 19.38万
依托单位：
RUSH UNIVERSITY MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-05-01 至 2017-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9052701
关键词：
ADP Ribose Transferases Actins Acute Adaptor Signaling Protein Address Adverse effects Animal Model Anti-Inflammatory Agents Antineoplastic Agents Apoptosis Apoptotic Bacteremia Biological Assay CASP1 gene CDC42 gene Cathepsins B Cell Count Cell Culture Techniques Cell Death Cell physiology Cells Chronic Clinical Cytokinesis Cytoplasm Cytoskeleton Data Dissection Environment Enzymes Epithelial Cells Event Exotoxins Guanosine Triphosphate Phosphohydrolases Healed Health Hela Cells Host Defense Immune Immune response Immunocompromised Host Impairment In Vitro Infection Inflammatory Inflammatory Response Link Mediating Membrane Molecular Monomeric GTP-Binding Proteins Nature Necrosis Nosocomial pneumonia Pathogenesis Patients Peptides Phosphoglycerate Kinase Play Pseudomonas Pseudomonas aeruginosa Publications Publishing Reporting Respiratory Failure Role Sepsis Signal Transduction Site Technology Tertiary Protein Structure Therapeutic Intervention Time Toxic effect Toxin Type III Secretion System Pathway Video Microscopy Virulence Virulence Factors Wound Healing Wound Infection base cancer therapy cell motility chemotherapy cytotoxicity healing in vivo mouse model outcome forecast pathogen pathogenic bacteria prevent wound

项目摘要

DESCRIPTION (provided by applicant): Pseudomonas aeruginosa (PA) is the most common cause of hospital-acquired pneumonia and respiratory failure, a leading cause of bacteremia and sepsis in patients receiving cancer drugs, and a killer of immunocompromised patients. PA possesses a number of cell-associated and secreted virulence factors. Chief amongst them is a Type III Secretion System (T3SS) apparatus which functions as a conduit, allowing PA to directly translocate a set of effector exotoxins, namely ExoS, ExoT, ExoU, and ExoY, into the target host cytoplasm where they modify host cellular processes and advance PA infections. ExoT is the only T3SS effector toxin that is present in all P. aeruginosa isolates examined thus far, suggesting a more fundamental role for this virulence factor in PA pathogenesis. Recently, we demonstrated that PA inhibits wound healing in a manner that is primarily dependent on its T3SS effector toxins. We found that ExoT playes a pivotal role in the T3SS-dependent inhibition of wound repair. We and others have further demonstrated that ExoT disrupts the actin cytoskeleton, prevents cell migration, interferes with cell-substratum contacts, and blocks cytokinesis at multiple steps. More recently, we have demonstrated that ExoT blocks the necrotic toxicity associated with T3SS apparatus insertion into target host membrane and reroutes the cell into apoptotic cell death. We propose that although T3SS is essential for PA infection, its activity triggers host inflammatory responses which are harmful to PA pathogenesis. To circumvent these harmful events, we hypothesize that PA employs ExoT as an anti-inflammatory agent to deal with this undesirable side effect of T3SS during infection. In this proposal, we will determine the mechanism(s) by which ExoT inhibits T3SS-induced pro-inflammatory associated cytotoxicity (Aim 1) and determine the role of ExoT as an anti-inflammatory agent in Pseudomonas aeruginosa in the context of wound infection in vivo (Aim 2). Findings from these studies will be essential to define a unique role of ExoT in PA pathogenesis, one that can be exploited for therapeutic intervention to treat PA in the setting of immune compromised patients and/or exploit the powerful ability of ExoT to induce none inflammatory apoptosis for cancer therapy.

描述（由申请人提供）：铜绿假单胞菌（PA）是医院获得性肺炎和呼吸衰竭的最常见原因，是接受癌症药物的患者发生菌血症和败血症的主要原因，也是免疫功能低下患者的杀手。其中最主要的是 III 型分泌系统 (T3SS) 装置，它充当导管，允许 PA 直接移位。一组效应外毒素，即 ExoS、ExoT、ExoU 和 ExoY，进入靶宿主细胞质，在那里它们改变宿主细胞过程并促进 PA 感染，ExoT 是因此检查的所有铜绿假单胞菌分离株中存在的唯一 T3SS 效应毒素。到目前为止，表明这种毒力因子在 PA 发病机制中具有更重要的作用。最近，我们证明 PA 以主要依赖于其 T3SS 效应子的方式抑制伤口愈合。我们发现 ExoT 在 T3SS 依赖性伤口修复抑制中发挥关键作用，我们和其他人进一步证明 ExoT 会破坏肌动蛋白细胞骨架，阻止细胞迁移，干扰细胞与基质的接触，并在多个步骤中阻断胞质分裂。最近，我们证明 ExoT 可以阻断与 T3SS 装置插入靶宿主膜相关的坏死毒性，并使细胞重新进入细胞凋亡状态。 T3SS 对于 PA 感染至关重要，其活性会引发对 PA 发病机制有害的宿主炎症反应，为了避免这些有害事件，我们发现 PA 采用 ExoT 作为抗炎剂来应对感染期间 T3SS 的不良副作用。在本提案中，我们将确定 ExoT 抑制 T3SS 诱导的促炎相关细胞毒性的机制（目标 1），并确定 ExoT 作为抗炎剂在体内伤口感染背景下的铜绿假单胞菌（目标 2）对于确定 ExoT 在 PA 发病机制中的独特作用至关重要，可用于在免疫受损的情况下进行治疗干预。患者和/或利用 ExoT 诱导非炎症性细胞凋亡的强大能力进行癌症治疗。

项目成果

期刊论文数量（7）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Apoptosis and Compensatory Proliferation Signaling Are Coupled by CrkI-Containing Microvesicles.

DOI：
10.1016/j.devcel.2017.05.014
发表时间：
2017-06-19
期刊：
Developmental cell
影响因子：
11.8
作者：
Gupta KH;Goldufsky JW;Wood SJ;Tardi NJ;Moorthy GS;Gilbert DZ;Zayas JP;Hahm E;Altintas MM;Reiser J;Shafikhani SH
通讯作者：
Shafikhani SH

CrkII/Abl phosphorylation cascade is critical for NLRC4 inflammasome activity and is blocked by Pseudomonas aeruginosa ExoT.

DOI：
10.1038/s41467-022-28967-5
发表时间：
2022-03-11
期刊：
Nature communications
影响因子：
16.6
作者：
Mohamed MF;Gupta K;Goldufsky JW;Roy R;Callaghan LT;Wetzel DM;Kuzel TM;Reiser J;Shafikhani SH
通讯作者：
Shafikhani SH

Presence of CrkI-containing microvesicles in squamous cell carcinomas could have ramifications on tumor biology and cancer therapeutics.

DOI：
10.1038/s41598-022-08905-7
发表时间：
2022-03-21
期刊：
Scientific reports
影响因子：
4.6
作者：
Mohamed MF;Al-Khudari S;Cassini-Vieira P;Erra A;Bagabas R;Houser T;Stenson K;Bhayani M;Jelinek MJ;Bishehsari F;Kuzel TM;Shafikhani SH
通讯作者：
Shafikhani SH

Pseudomonas aeruginosa ExoT induces G1 cell cycle arrest in melanoma cells.