Multiphoton Imaging and Rheology of Fibrosis Models

纤维化模型的多光子成像和流变学

• 批准号: 7407804
• 负责人: Christopher B Raub
• 金额: $ 3.13万
• 依托单位: UNIVERSITY OF CALIFORNIA-IRVINE
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7407804
• 关键词: Affect; Animal Model; Arterial Fatty Streak; Asthma; Basic Science; Biochemical; Biological Assay; Blood Vessels; Clinic; Collagen; Data; Deposition; Diagnosis; Disease; Electrons; Engineering; Environment; Fibroblasts; Fibrosis; Fluorescence; Gel; Generations; Human; Hydroxyproline; Image; Light; Mechanics; Mediating; Microscopy; Modeling; Monitor; Patients; Photons; Polymers; Property; Rattus; Rheology; Scanning Electron Microscopy; Signal Transduction; Spectrum Analysis; Structure; Tissue Engineering; Tissue Model; Tissues; Variant; Wound Healing; asthmatic airway; crosslink; density; fluorescence imaging; image processing; in vivo; novel; second harmonic; theories; tool; tumor; two-photon

DESCRIPTION (provided by applicant): Collagen structure, density, and concentration changes in tissues affected by various diseases. Subepithelial fibrosis in asthmatic airways, atherosclerotic lesions in blood vessels, and matrix changes near tumors all can be studied using multiphoton microscopy. Collagen responds to near infrared light by second harmonic generation (SHG, photons emitted at half the excitation wavelength) and two-photon fluorescence (TPF). Whereas SHG originates from electrons within the helical fibril structure, TPF arises from certain enzymatic and nonenzymatic crosslinks. By imaging SHG and TPF in acellular collagen, engineered fibrosis models, and rat airway fibrosis models, this proposal will characterize the two signals, explaining reasons for the signal variation by fitting quantitative image data to models and correlating data with: 1) collagen gel microstructure, cross linking , and mechanical properties, assessed by scanning electron microscopy, biochemical assays, and rheology, respectively; 2) fibroblast-mediated collagen deposition, degradation, and remodeling, assessed by hydroxyproline assays, zymography, and multiphoton imaging, and; 3) an in vivo wound healing environment, from a rat model of asthma. This proposal seeks to develop multiphoton imaging of SHG and TPF as a tool to predict and monitor mechanical and structural properties of engineered tissue and of shallow fibrosis in animal models and clinically in humans. Novel image processing tools, such as image correlation spectroscopy, will be applied to SHG and TPF images to estimate microstructurai parameters that serve as inputs to a structural mechanical model of tissue, derived from semiflexible polymer network theory. Automated and standardized image processing and mechanical property modeling developed by this project will find applications in basic research and in the clinic, where noninvasively-collected information about tissue mechanical properties will aid in the study of engineered tissues, diseased tissues from patients, and in diagnosis and treatment of fibrotic diseases.

描述（由申请人提供）：受各种疾病影响的组织中胶原蛋白的结构、密度和浓度变化。哮喘气道的上皮下纤维化、血管中的动脉粥样硬化病变以及肿瘤附近的基质变化都可以使用多光子显微镜进行研究。胶原蛋白通过产生二次谐波（SHG，以激发波长一半发射的光子）和双光子荧光 (TPF) 来响应近红外光。 SHG 源自螺旋原纤维结构内的电子，而 TPF 则源自某些酶促和非酶促交联。通过对无细胞胶原、工程纤维化模型和大鼠气道纤维化模型中的 SHG 和 TPF 进行成像，该提案将表征这两个信号，通过将定量图像数据拟合到模型并将数据与以下各项相关联来解释信号变化的原因：1) 胶原凝胶微观结构、交联和机械性能，分别通过扫描电子显微镜、生化测定和流变学进行评估； 2) 成纤维细胞介导的胶原蛋白沉积、降解和重塑，通过羟脯氨酸测定、酶谱分析和多光子成像进行评估； 3）来自哮喘大鼠模型的体内伤口愈合环境。该提案旨在开发 SHG 和 TPF 的多光子成像，作为预测和监测动物模型和人类临床工程组织和浅层纤维化的机械和结构特性的工具。新型图像处理工具（例如图像相关光谱）将应用于 SHG 和 TPF 图像，以估计微观结构参数，这些参数可作为源自半柔性聚合物网络理论的组织结构力学模型的输入。该项目开发的自动化和标准化图像处理和机械性能建模将在基础研究和临床中找到应用，其中无创收集的有关组织机械性能的信息将有助于工程组织、患者患病组织的研究和诊断和纤维化疾病的治疗。