Quantitative optical imaging of cilia-driven fluid flow

纤毛驱动流体流动的定量光学成像

• 批准号: 8849968
• 负责人: Michael Andrew Choma
• 金额: $ 41万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2016-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8849968
• 关键词: Accounting; Allergens; Animal Model; Asthma; Biological; Biological Assay; Biological Markers; Biology; Biomechanics; Biomimetics; Cells; Child; Childhood; Cilia; Clinical; Cues; Defect; Detection; Development; Devices; Diagnosis; Diagnostic; Diffusion; Disease; Embryo; Embryonic Development; Frequencies; Genes; Health; Human; Image; Imaging technology; Impairment; Lead; Light; Lighting; Liquid substance; Lung; Lung diseases; Magnetic Resonance Imaging; Measurement; Measures; Mechanics; Methods; Microfluidics; Molecular Genetics; Molecular Motors; Morbidity - disease rate; Mucous body substance; Mus; Nature; Neonatal; Newborn Infant; Optical Coherence Tomography; Optical Methods; Optics; Pattern; Performance; Phenotype; Physiology; Predisposition; Primary Ciliary Dyskinesias; Process; Property; Public Health; Research; Role; Severities; Shapes; Signal Transduction; Signaling Protein; Skin; Speed; Structure; Surface; Tadpoles; Technology; Testing; Time; Translating; Velocimetries; Viscosity; Work; Xenopus; base; clinical care; clinically significant; density; detector; digital; extracellular; fluid flow; genetic manipulation; imaging system; improved; interest; lens; mortality; mouse model; notch protein; novel; optical imaging; optical switch; particle; pathogen; planar cell polarity; quantitative imaging; respiratory; vector

DESCRIPTION (provided by applicant): Respiratory diseases are major causes of pediatric morbidity and mortality. These diseases are incompletely understood, which is a barrier to improving clinical care. Therefore, new mechanisms of disease need to be discovered. Optical imaging (e.g. optical coherence tomography [OCT]) will enable these discoveries since traditional imaging (e.g. x-ray, CT, MRI) cannot visualize structures smaller than ~1 mm. Microfluidic-scale cilia-driven fluid flow clears pathogen and allergen-containing mucus out of the lungs, yet we currently lack quantitative imaging technologies to characterize their flow performance. Moreover, while ciliary defects are traditionally considered a feature of rare but severe diseases (e.g. primary ciliary dyskinesia), development of biomechanical biomarkers extracted from quantitative flow imaging will allow us to test a paradigm-shifting hypothesis: intermediate defects in ciliary performance that are undetectable by current diagnostics are major modifiers of clinical severity in common respiratory diseases (e.g. asthma). Our research therefore has three aims. First, we will develop high-speed, cosine ambiguity-free Doppler OCT imaging systems. Cilia-driven fluid flow is three-dimensional in nature and not amenable to simplifying geometric assumptions such as parabolic flow profile. Traditional Doppler imaging suffers from cosine ambiguity that precludes the measurement of three-component flow velocities (v=vxi+vyj+vzk). We will develop a novel class of OCT interferometers that will enable three-dimensional, three-component flow imaging that will be demonstrated using the ciliated skin of Xenopus (tadpole) embryos, an important animal model in ciliary biology. Second, we will develop quantitative imaging assays of ciliary function that exploit cilia-driven microfluidic mixing. Taking a cue from work in biomimetic cilia, we have (a) demonstrated that ciliated biological surfaces can drive microfluidic mixing and (b) developed a novel microfluidic chip that uses a ciliated biological surface as a microfluidic "component." Building on these results, we will demonstrate that our microfluidic mixing-based assay can quantify biologically relevant perturbations to ciliary physiology including increased fluid viscosity and altered planar cell polarity. Third, we will demonstrate intermediate defects in Xenopus and mouse ciliary function using quantitative imaging. We will target two different classes of genes relevant in the performance of a ciliated surface in Xenopus embryos: ciliary molecular motors and notch signaling proteins (notch signaling controls the density of ciliated cells on the embryo skin). Given the importance of mouse models of pediatric respiratory disease, it is critical to demonstrate that our optical methods can be used to quantify the performance of mouse respiratory cilia. Moreover, this is an important step towards translating our diagnostic technologies to use in humans. We propose to use flow imaging to quantify performance modified by increased fluid viscosity (mechanical perturbation to decrease ciliary beat frequency) and increased extracellular ATP (pharmacological perturbation to increase ciliary beat frequency).

描述（由申请人提供）：呼吸道疾病是小儿发病率和死亡率的主要原因。这些疾病尚不完全了解，这是改善临床护理的障碍。因此，需要发现新的疾病机制。光学成像（例如，光学相干断层扫描[OCT]）将使这些发现能够实现这些发现，因为传统成像（例如X射线，CT，MRI）无法可视化小于〜1 mm的结构。微流体尺度的纤毛驱动的流体流从肺中清除病原体和含有过敏原的粘液，但目前我们缺乏定量成像技术来表征其流动性能。此外，虽然传统上认为睫状缺陷被认为是罕见但严重疾病的特征（例如原发性纤毛运动障碍），但从定量流量成像中提取的生物力学生物标志物的发展将使我们能够测试范式分类的假设：通过当前诊断性的固定性较高的辅助性均具有较高的诊断性（包括诊断性的均为诊断性），这是诊断性的不可测量的（哮喘）。因此，我们的研究有三个目标。首先，我们将开发高速，无歧义的无歧义多普勒OCT成像系统。纤毛驱动的流体流量本质上是三维的，不适合简化几何假设，例如抛物线流谱。传统的多普勒成像遭受余弦的歧义，从而排除了三组分流速度的测量（V = VXI+VYJ+VZK）。我们将开发一类新型的OCT干涉仪，该类别将实现三维三组分流量成像，该成像将使用Xenopus（Tadpole）胚胎的纤毛皮肤（纤毛生物学中的重要动物模型）进行证明。其次，我们将开发用于利用纤毛驱动的微流体的睫状功能的定量成像测定法 混合。从仿生纤毛中的工作中获得提示，我们（a）证明了纤毛的生物表面可以驱动微流体混合，并且（b）开发了一种新型的微流体芯片，该芯片使用纤毛的生物表面作为微富集的“成分”。在这些结果的基础上，我们将证明我们的微流体混合测定可以量化与纤毛生理的生物学相关扰动，包括增加液体粘度和平面细胞极性改变。第三，我们将使用定量成像来证明异武和小鼠睫状功能中的中间缺陷。我们将针对两种不同类别的基因，其中与脱爪卷胚胎中纤毛表面的性能相关：纤毛分子电机和Notch信号传导蛋白（Notch信号传导控制胚胎皮肤上纤毛细胞的密度）。鉴于小鼠呼吸道疾病的小鼠模型的重要性，至关重要的是，可以证明我们的光学方法可用于量化小鼠呼吸纤毛的性能。此外，这是翻译我们用于人类使用的诊断技术的重要一步。我们建议使用流量成像来量化通过液体粘度提高（机械扰动以降低睫状节拍频率）和增加细胞外ATP（药理学扰动以增加睫状节拍频率）。