INSPIRE: How Do Cilia-driven Flows Shape the Chemical and Mechanical Environment in Bacteria-Host Associations?

这是一项INSPIRE奖，由生物科学委员会、分子和细胞生物科学部(MCB)、系统和合成生物学(SSB)计划以及工程委员会(土木、机械和制造创新部门(CMMI)、动力学、控制和系统诊断(DCSD)计划)共同资助。有益细菌和致病细菌一样，通常沿着粘膜上皮与宿主细胞相互作用。这些表面通常排列着密集的可移动纤毛场，既有产生粘液纤毛流的生物力学功能，也有检测和呈现分子信号的生化功能。这个项目的目标是调查健康和疾病的纤毛组织之间的动态联系。该项目假设纤毛产生的流动影响细菌与宿主的相互作用，从而挑战生物学中的传统观点，即细菌招募主要归因于主动的细菌行为和被动扩散，忽视了纤毛产生的流动对运动和质量运输的影响。这项研究的更广泛的影响是，这个项目在不同学科的交叉提供了极好的教育和培训机会，同时也在微生物宿主定植方面产生了新的见解，这可能揭示出有效的策略的途径，以阻止病原体定植宿主，同时增强有益组织的定植潜力。该方法结合了从尖端成像和遗传工具到新型微流控技术的跨学科方法，所有这些方法都与强大的数学和计算框架相结合，以研究细菌-宿主关联中的这一基本问题，即纤毛生成的流动在塑造这些关联中的作用。该项目将建立一个定量和预测模型，该模型由两个互补的模型系统的实验测试提供信息：1.体内无脊椎动物模型：鱿鱼-弧菌系统是在其自然流体环境中运行的完整动物宿主，将被用于研究宿主的纤毛上皮如何启动与其天然的、流传的细菌群落的接触。鱿鱼-弧菌协会中的事件与宿主对人类相关病原体的反应有显著的相似之处，同时仍然可以进行成像和实验操作。在硅微流控技术中：经过适当设计的微流控通道将被用作分析细菌细胞对精心控制的微环境的反应的工具。这种方法旨在补充鱿鱼弧菌的研究，提供一个平台，分离在体内模型中观察到的化学梯度和流动剪切梯度，从而允许揭开决定细菌行为的机制，并可能触发细菌基因表达的变化，导致从自由游泳状态向生物膜状态的转变。

This is an INSPIRE award that was co-funded by the Biosciences Directorate, Division of Molecular and Cellular Biosciences (MCB), Systems and Synthetic Biology (SSB) program, and the Engineering Directorate, Division of Civil, Mechanical, and Manufacturing Innovation (CMMI), Dynamics, Control and System Diagnostics (DCSD) program. Beneficial and pathogenic bacteria alike, commonly interact with host cells along mucosal epithelia. These surfaces are often lined with dense fields of motile cilia that serve both a biomechanical function for generating mucociliary flows, and a biochemical function to detect and present molecular signals. The goal of this project is to investigate a the dynamic association of healthy and diseased ciliated tissues. The project posits that cilia-generated flows influence bacteria-host interactions, thereby challenging the conventional view in biology that attributes bacterial recruitment mostly to active bacterial behavior and passive diffusion, ignoring the effect of cilia-generated flows on both motility and mass transport. The broader impacts of this study are that this project provides excellent educational and training opportunities at the intersection of disciplines, while also generating new insight in microbial host colonization that are likely to reveal avenues for impactful strategies to block pathogenic bacteria from colonizing the host, while enhancing the colonization potential of beneficial organisms.The approach incorporates interdisciplinary methods, ranging from cutting-edge imaging and genetic tools to novel microfluidic technologies, all combined with powerful mathematical and computational framework, to investigate this fundamental problem in bacteria-host associations, namely, the role of cilia-generated flows in shaping these associations. The project will build a quantitative and predictive model that is informed by experimental assays in two complementary model systems:1. In vivo invertebrate model: the squid-vibrio system, an intact animal host operating in its natural fluid environment, will be used to study how the host's ciliated epithelium initiates contact with its native, flow-borne bacterial community. Events in the squid-vibrio association share remarkable similarities with host responses to human-relevant pathogens, while still being accessible to imaging and experimental manipulation.2. In silico microfluidics: properly designed microfluidic channels will be used as a tool to analyze the response of bacterial cells to carefully controlled microenvironment. This approach is aimed at complementing the squid-vibrio studies by providing a platform that isolates the chemical gradients and flow shear gradients observed in the in vivo model, thus allowing to unravel the mechanisms dictating bacterial behavior and possibly triggering the changes in bacterial gene expressions causing the transition from free-swimming to biofilm state.