CAREER: A Multi-phase Biosensing Approach towards Point-of-Care Evaluation of Pseudomonas aeruginosa Virulence in Infected Chronic Wounds

职业生涯：用于护理点评估慢性感染伤口中铜绿假单胞菌毒力的多阶段生物传感方法

• 批准号: 2340867
• 负责人: Jordon Gilmore
• 金额: $ 55万
• 依托单位: Clemson University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-05-01 至 2029-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2340867&HistoricalAwards=false
• 关键词: CAREER; Multi; phase; Biosensing; Approach

Infections from bacteria that are resistant to antibiotics are a major source of healthcare costs ($4.6B annually) and treatment complications that lead to death. More than 2.8 million drug-resistant infections occur each year in the US, with more than 35,000 deaths despite widespread availability of antibiotics, mostly because they are not effective against drug-resistant bacteria. The likelihood of complication or death is increased for patients with weakened immune systems. The bacteria form complex structures called biofilms that protect themselves from antibiotic treatment. These biofilms are developed through a bacteria cell communication strategy called quorum sensing. This project seeks to study how quorum sensing can be tracked by an inexpensive, rapid, and flexible sensor that provides information on how quickly bacteria are growing and how fast biofilms are being developed. The sensor developed and used in this study is unique because of its flexibility and ability to measure electrical and chemical activity related to bacteria growth. The long-term research goal of this project is to make possible the fast (less than 5 minutes) determination of infection so that the correct antibiotics and dosage can be delivered at the most opportune time. Importantly, this sensing approach can also be used in other applications, like water filtering and agriculture. The educational goal of this project is to support research and graduate education for underrepresented students, especially veterans and non-traditional students. These students often face unique obstacles to participating in traditional undergraduate research experiences, such as work, family, or military commitments. This project will address these challenges through a combination of coursework, research, and workshop experiences designed to expose and engage students in new ideas and job opportunities.The primary motivation for this project is the development of a strategy to quickly measure bacterial infections in chronic, non-healing wounds for the inhibition of antibiotic resistance/tolerance, which is both an important societal problem and of fundamental scientific interest. More than 2.8 million antimicrobial-resistant infections occur each year in the US, with more than 35,000 deaths despite widespread availability of antibiotics in large part because they are ineffective against resistant strains and biofilms, especially but not only in immune compromised patients. The research objective of this project is to leverage concentration-dependent quorum sensing (QS) molecules to quantify key transitions in biofilm formation that relate to the progression of virulence in bacterial pathogens. This project focuses on Pseudomonas aeruginosa biofilm formation and virulence, as a model system for other bacterial pathogens commonly found in chronic wounds. This project uses a nonwoven nanofiber composite electrode design in electrochemical impedance spectroscopy and voltammetric experiments to quantify virulence progression via pyocyanin and 3OC12HSL (QS molecules used to mediate virulence) detection and quantification. The following scientific contributions will result from this work: 1) A directly quantifiable relationship between bacterial concentration (P. aeruginosa), QS molecule concentration (Pyocyanin and AHLs - 3OC12HSL), and stage of biofilm development; 2) Enablement of a flexible, tunable voltametric sensor that offers highly sensitive and specific electrochemical detection of redox species while being easily incorporated into wearable fabrics or wound dressings given its bio-textile design; and 3) The functionalization of nanofiber composite aptasensors, enabling generation of quantifiable electrochemical signals to greatly reduce the Limit of Detection (LOD) and improve specificity. This work addresses the critical challenge of quantifying species-specific signaling molecules associated with progression of bacterial load (bioburden). The long-term importance of this work is increased understanding of more effective treatment timing, while reducing the risk for development of drug resistance. Understanding the precise moments in which a bacterial pathogen may be advancing in virulence is important for any organism that may be infected by these bacteria, including plants, animals, and humans.This project is jointly funded by the Biosensing Program and the Established Program to Stimulate Competitive Research (EPSCoR).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

对抗生素有抗药性的细菌引起的感染是医疗费用（每年 4.6B 美元）和导致死亡的治疗并发症的主要来源。尽管抗生素已广泛使用，但美国每年仍发生超过 280 万例耐药感染，仍有超过 35,000 人死亡，主要原因是抗生素对耐药细菌无效。免疫系统较弱的患者出现并发症或死亡的可能性会增加。细菌形成称为生物膜的复杂结构，可以保护自己免受抗生素治疗。这些生物膜是通过称为群体感应的细菌细胞通讯策略形成的。该项目旨在研究如何通过廉价、快速且灵活的传感器跟踪群体感应，该传感器提供有关细菌生长速度和生物膜形成速度的信息。本研究中开发和使用的传感器是独一无二的，因为它具有灵活性和测量与细菌生长相关的电和化学活动的能力。该项目的长期研究目标是使快速（不到5分钟）确定感染成为可能，以便在最合适的时间提供正确的抗生素和剂量。重要的是，这种传感方法还可以用于其他应用，例如水过滤和农业。该项目的教育目标是支持代表性不足的学生，特别是退伍军人和非传统学生的研究和研究生教育。这些学生在参与传统的本科研究经历时经常面临独特的障碍，例如工作、家庭或军事承诺。该项目将通过课程作业、研究和研讨会经验相结合来应对这些挑战，旨在让学生接触新想法和工作机会并让他们参与其中。该项目的主要动机是制定一种快速测量慢性、抑制抗生素耐药性/耐受性的不愈合伤口，这既是一个重要的社会问题，又具有根本的科学意义。尽管抗生素已广泛使用，但美国每年仍发生超过 280 万例抗菌药物耐药性感染，其中超过 35,000 人死亡，这在很大程度上是因为抗生素对耐药菌株和生物膜无效，尤其是（但不仅限于）免疫受损的患者。该项目的研究目标是利用浓度依赖性群体感应（QS）分子来量化与细菌病原体毒力进展相关的生物膜形成的关键转变。该项目重点研究铜绿假单胞菌生物膜的形成和毒力，作为慢性伤口中常见的其他细菌病原体的模型系统。该项目在电化学阻抗谱和伏安实验中使用非织造纳米纤维复合电极设计，通过绿脓素和 3OC12HSL（用于介导毒力的 QS 分子）检测和定量来量化毒力进展。这项工作将产生以下科学贡献： 1) 细菌浓度（铜绿假单胞菌）、QS 分子浓度（绿脓菌素和 AHL - 3OC12HSL）和生物膜发育阶段之间的直接可量化关系； 2) 实现灵活、可调谐的伏安传感器，该传感器可对氧化还原物质进行高灵敏度和特异性电化学检测，同时由于其生物纺织品设计，可轻松融入可穿戴织物或伤口敷料中； 3）纳米纤维复合适体传感器的功能化，能够生成可量化的电化学信号，从而大大降低检测限（LOD）并提高特异性。这项工作解决了量化与细菌负荷（生物负载）进展相关的物种特异性信号分子的关键挑战。这项工作的长期重要性是增加对更有效治疗时机的了解，同时降低产生耐药性的风险。了解细菌病原体毒力增强的精确时刻对于任何可能被这些细菌感染的生物体（包括植物、动物和人类）都很重要。该项目由生物传感计划和既定刺激计划共同资助竞争性研究 (EPSCoR)。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。