Biomimetic alveolar interstitium model for investigation of nanomaterials-induced fibrogenesis

项目摘要/摘要 虽然快速发展的纳米技术在电子、能源、医疗保健和许多领域显示出了希望 在其他领域，人们越来越关注基因工程对健康的不利影响 纳米材料。活体研究表明，吸入的碳纳米管可以迅速进入肺部 间质刺激胶原生成并诱导进行性间质性肺纤维化，是一种致命的和 没有已知的有效治疗方法的不治之症。为了评估纳米材料的毒性，动物研究 是必要的，但昂贵，耗时和设备有限；而目前的大多数体外模型 从一系列缺点来看，最重要的是，它们缺乏体内微环境的特点，导致 体内关键细胞表型和反应性的丧失。因此，迫切需要在 与生理相关的体外模型为毒理学提供可靠、快速和廉价的方法 纳米材料的研究和风险评估。肺间质细胞外基质明显 纳米级的形貌，表现出不同程度的硬度，并富含间隙流体。这个 生理性的呼吸运动也会产生周期性的机械压力。尽管物理(衬底) 纳米形貌和硬度)和机械(流体诱导力和机械应变)的关键提示 影响体内许多发育、生理和病理过程，并具有深远的 在体外对细胞表型和功能的影响，目前还没有关于整合这些因素的报道。 成为毒物学研究的单一平台。我们的假设是间质纤维化反应 在体外，纳米材料可以在生理相关的微环境中更准确地进行评估。 因此，本项目的目标是开发一种结合物理模型的肺泡间质模型。 以及与生理相关的机械线索，以研究纳米材料诱导的肺纤维化。我们 已经组建了一个跨学科的研究团队，在体内和体外进行纳米毒理学研究， 并提供了强有力的证据，证明纳米形貌、硬度和流体剪应力具有深远的影响 对细胞行为的影响。基于令人信服的初步结果，我们提出了本项目的两个具体目标：(1) 剖析底物纳米拓扑学和刚性调制的人肺成纤维细胞传感纳米材料，以及(2) 构建集成肺部关键物理、机械和结构特征的微流控平台 间质，以评估纳米材料诱导的纤维化。这一项目的顺利完成将推进 我们对细胞行为的物理和机械调节的基本理解，并开发了一种新的， 仿生间质微环境以超前的“经典”体外细胞毒方法。这 仿生模型有望填补当前体外模型与传统模型之间的知识和技术空白 动物研究，并有可能促进纳米技术的可持续发展。

PROJECT SUMMARY/ABSTRACT While the rapidly evolving nanotechnology has shown promise in electronics, energy, healthcare and many other fields, there is an increasing concern about the adverse health consequences of engineered nanomaterials. In vivo studies have shown that inhaled carbon nanotubes can rapidly enter the lung interstitium to stimulate collagen production and induce progressive interstitial lung fibrosis, which is a fatal and incurable disease with no known effective treatment. To evaluate the toxicity of nanomaterials, animal studies are necessary but costly, time-consuming and facility limited; while the majority of current in vitro models suffer from a series of drawbacks, most importantly, they lack characteristics of in vivo microenvironment, leading to losses of critical in vivo cell phenotypes and responsiveness. There is, therefore, a critical need to develop in vitro models of physiological relevance to provide reliable, rapid and inexpensive methods for toxicology studies and risk assessment of nanomaterials. The extracellular matrix of lung interstitium manifests significant nanoscale topographies, exhibits various degrees of stiffness, and is enriched with interstitial fluids. The physiological breathing movements also provide cyclic mechanical strain. Although the physical (substrate nanotopography and stiffness) and mechanical (fluid-induced forces and mechanical strain) cues critically influence numerous developmental, physiological and pathological processes in vivo and have a profound influence on cell phenotype and function in vitro, there has been no effort reported on integrating these factors into a single platform for toxicology studies. Our hypothesis is that the interstitial fibrotic response to nanomaterials in vitro can be more accurately evaluated in a physiologically relevant microenvironment. Therefore, the objective of this project is to develop an alveolar interstitium model integrated with the physical and mechanical cues of physiological relevance to investigate nanomaterials induced lung fibrogenesis. We have assembled an interdisciplinary research team to carry out nanotoxicology studies both in vivo and in vitro, and provided strong evidence that nanotopography, stiffness and fluidic shear stress have profound influences on cell behavior. Based on the compelling preliminary results, we propose two Specific Aims in this project: (1) dissect substrate nanotopography and stiff modulated human lung fibroblast sensing nanomaterials, and (2) build a microfluidic platform integrated with key physical, mechanical and structural characteristics of lung interstitium to assess nanomaterials induced fibrogenesis. Successful completion of this project will advance our fundamental understanding of physical and mechanical modulation of cell behavior and develops a novel, biomimetic interstitium microenvironment to advances over the “classic” in vitro cytotoxicity methods. This biomimetic model is expected to fill the knowledge and technology gaps between current in vitro models and animal studies, and potentially promote sustainable development of nanotechnology.