CAREER: Impact of MRI contrast agent design on nanoscale interactions with neutrophils and platelets

了解纳米颗粒的特性如何介导它们与体内血细胞的相互作用，对于提高它们的安全性和有效性至关重要。递送到血流中的纳米颗粒被红细胞、各种白色血细胞和血小板包围。尽管血液的复杂性，大多数研究开发的纳米粒子成像应用集中在评估脱靶纳米粒子与一个亚型的白色血细胞称为巨噬细胞的相互作用。巨噬细胞是人体防御外来物体的防御机制的一部分，并且已知可以将纳米载体隔离在体内。尽管血小板和其他白色血细胞如嗜中性粒细胞的丰度，这些血细胞往往被忽略在纳米颗粒显像剂的设计。一旦激活，中性粒细胞和血小板可以粘在一起，形成细胞聚集体，阻止血液流动，就像一团头发堵塞排水管一样。这个CAREER项目将产生关于金属氧化物纳米颗粒的物理特性（其金属含量，表面涂层和尺寸）如何影响与中性粒细胞和血小板的相互作用的新知识。Bennewitz博士将研究纳米颗粒设计如何介导细胞摄取和运输，中性粒细胞和血小板的激活，以及它们在静态和动态系统中的下游细胞-细胞相互作用。该项目将通过更智能的设计策略来最大限度地减少脱靶效应，从而为磁共振成像创造更安全，更有效的纳米粒子造影剂。综合教育计划将针对来自西弗吉尼亚州农村，低收入和第一代大学家庭的服务不足的学生，他们面临着不推进教育的风险。总的来说，该教育计划将激发西弗吉尼亚州从学前班到高中学生的所有年龄组对STEM的兴趣。通过结合动手研究，体验式学习，艺术和科学的创造性融合，以及接触纳米技术，成像和生物材料的真实的世界应用，这些推广活动将激励下一代的年轻科学家和工程师。传统的新型纳米粒子造影剂的测试依赖于评估与巨噬细胞的脱靶相互作用，忽略了中性粒细胞和血小板。活化的中性粒细胞和血小板可以形成嗜中性粒细胞-血小板聚集体，其触发下游损伤，包括释放称为中性粒细胞胞外陷阱的网状DNA纤维。中性粒细胞胞外陷阱引起内皮损伤、血小板活化和中性粒细胞募集以促进血管阻塞。因此，迫切需要阐明纳米粒子造影剂如何与中性粒细胞和血小板相互作用以最大化安全性。Bennewitz博士的研究小组已经表明，纳米颗粒造影剂涂层和金属含量通过中性粒细胞胞外陷阱、活性氧和细胞因子的差异释放来调节中性粒细胞功能。该CAREER项目旨在确定用于磁共振成像的金属氧化物纳米颗粒的物理特性如何介导与中性粒细胞和血小板在互补系统中的相互作用，包括静态体外测定，微流控芯片和原理验证小鼠模型。中心假设是纳米颗粒造影剂的物理性质调节中性粒细胞和血小板纳米颗粒转运、细胞活化、嗜中性粒细胞-血小板聚集体形成、中性粒细胞胞外陷阱的释放和血栓形成。中心假设将通过以下研究目标进行检验：（1）研究中性粒细胞和血小板中的金属氧化物纳米颗粒摄取和转运（2-3）评价静态和动态流动条件下金属氧化物纳米颗粒介导的中性粒细胞和血小板活化、聚集和中性粒细胞胞外陷阱释放。该项目将是变革性的，因为Bennewitz博士将能够确定氧化锰纳米颗粒、氧化铁纳米颗粒和常规钆螯合物造影剂如何影响体外和体内嗜中性粒细胞-血小板串扰、中性粒细胞胞外陷阱和血栓形成，以提高造影剂的安全性。这个职业项目的教育目标是：（1）通过向上拓展计划，接待10名西弗吉尼亚州农村低收入高中生进行暑期实践研究。学生将接触到纳米粒子的合成和孵育研究与中性粒细胞和血小板在静态和动态系统。(2)创建和传播生物医学工程模块通过西弗吉尼亚州科学公共外展队全州4,000初中和高中学生。两个实践活动将被整合到演示文稿中，以激发学生对荧光成像和聚合物刺激驱动交付的兴趣，这是该项目的两个关键研究概念。(3)设计和领导一个互动的科学满足艺术活动的重点是荧光绘画下的黑光灯为10岁及以下的儿童在火花！想象力和科学中心该教育计划将培养对STEM教育和职业的兴趣，为服务不足的西弗吉尼亚州学生和公众。本科生和研究生将获得宝贵的指导和教学经验，通过他们在创建和传播的推广活动，这将加强他们的信心，领导和保留在干他们的整体作用。该项目由CBET内的纳米级相互作用计划和刺激竞争研究的既定计划（EPSCoR）共同资助。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Understanding how nanoparticle characteristics mediate their interactions with blood cells in the body is crucial to promoting their safety and effectiveness. Nanoparticles delivered to the bloodstream are surrounded by red blood cells, a variety of white blood cells, and platelets. Despite blood’s complexity, most studies developing nanoparticles for imaging applications have focused on assessing off-target nanoparticle interactions with a subtype of white blood cells called macrophages. Macrophages are part of the body’s defense mechanism against foreign objects and are known to sequester nanocarriers in the body. Despite the abundance of platelets and other white blood cells such as neutrophils, these blood cells are often ignored in the design of nanoparticle imaging agents. Upon activation, neutrophils and platelets can stick together to form cellular aggregates that can block blood flow, just as a clump of hair clogs a drainpipe. This CAREER project will generate new knowledge on how the physical characteristics of metal oxide nanoparticles (their metal content, surface coating, and size) impact interactions with neutrophils and platelets. Dr. Bennewitz will investigate how nanoparticle design mediates cell uptake and transport, activation of neutrophils and platelets, and their downstream cell-cell interactions in static and dynamic systems. This project will lead to the creation of safer and more effective nanoparticle contrast agents for magnetic resonance imaging by smarter design strategies to minimize off-target effects. The integrated education plan will target underserved students from rural, low-income, and first-generation college households in West Virginia, who are at-risk for not advancing their education. Collectively, the education plan will spark interest in STEM for all age groups from preschool to high school students in West Virginia. By combining hands-on research, experiential learning, creative integration of art and science, and exposure to real world applications in nanotechnology, imaging, and biomaterials, these outreach activities will inspire the next generation of young scientists and engineers.Conventional testing of novel nanoparticle contrast agents relies on evaluating off-target interactions with macrophages, disregarding neutrophils, and platelets. Activated neutrophils and platelets can form neutrophil-platelet aggregates that trigger downstream damage including release of web-like DNA fibers called neutrophil extracellular traps. Neutrophil extracellular traps provoke endothelial injury, platelet activation, and neutrophil recruitment to promote vessel blockage. Thus, there is a critical need to elucidate how nanoparticle contrast agents interact with neutrophils and platelets to maximize safety. Dr. Bennewitz’s group has shown that nanoparticle contrast agent coating and metal content modulates neutrophil function via differential release of neutrophil extracellular traps, reactive oxygen species, and cytokines. This CAREER project aims to determine how the physical characteristics of metal oxide nanoparticles used in magnetic resonance imaging mediate interactions with neutrophils and platelets in complementary systems including static in vitro assays, microfluidic chips, and a proof-of-principle mouse model. The central hypothesis is that the physical properties of nanoparticle contrast agents modulate neutrophil and platelet nanoparticle transport, cell activation, neutrophil-platelet aggregate formation, release of neutrophil extracellular traps, and thrombosis. The central hypothesis will be tested with the following research objectives: (1) Investigate metal oxide nanoparticle uptake and transport in neutrophils and platelets (2-3) Evaluate metal oxide nanoparticle-mediated neutrophil and platelet activation, aggregation, and release of neutrophil extracellular traps under static and dynamic flow conditions. This project will be transformative, as Dr. Bennewitz will be able to determine how manganese oxide nanoparticles, iron oxide nanoparticles, and conventional gadolinium chelate contrast agents impact neutrophil-platelet crosstalk, neutrophil extracellular traps, and thrombosis in vitro and in vivo to enhance contrast agent safety. The educational objectives of this CAREER project are to: (1) Host 10 rural, low-income West Virginia high school students in hands-on summer research through the Upward Bound Program. Students will be exposed to nanoparticle synthesis and incubation studies with neutrophils and platelets in static and dynamic systems. (2) Create and disseminate a Biomedical Engineering module to 4,000 middle and high school students state-wide via the West Virginia Science Public Outreach Team. Two hands-on activities will be integrated into the presentation to spark student interest in fluorescence imaging and polymer stimulus driven delivery, two key research concepts of this project. (3) Design and lead an interactive science meets art activity focused on fluorescent painting under blacklights for children aged 10 and under at the Spark! Imagination and Science Center. The education plan will cultivate interest in STEM education and careers for underserved West Virginia students and the public. Undergraduate and graduate students will gain valuable mentoring and teaching experience via their integral roles in creating and disseminating the outreach activities which will bolster their confidence, leadership, and retention in STEM. This project is jointly funded by the Nanoscale Interactions Program within CBET 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.