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(申请人提供)：受各种疾病影响的组织中的胶原结构、密度和浓度变化。哮喘呼吸道的上皮下纤维化、血管中的动脉粥样硬化病变以及肿瘤周围的基质变化都可以用多光子显微镜来研究。胶原蛋白通过二次谐波(倍频，激发波长的一半)和双光子荧光(TPF)对近红外光做出反应。SHG来源于螺旋纤维结构中的电子，而TPF来源于某些酶和非酶的交联键。通过对无细胞胶原、工程化纤维化模型和大鼠呼吸道纤维化模型中SHG和TPF的成像，这项建议将表征这两种信号，并通过将定量图像数据与模型相匹配并将数据与以下各项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、生化分析和流变学进行评估；2)成纤维细胞介导的胶原沉积、降解和重塑；以及3)来自哮喘大鼠模型的体内伤口愈合环境。这项建议旨在开发SHG和TPF的多光子成像，作为一种工具来预测和监测工程组织的机械和结构特性，以及动物模型和临床上的浅层纤维化。新的图像处理工具，如图像相关光谱，将应用于SHG和TPF图像，以估计微结构参数，作为组织结构力学模型的输入，该模型源于半柔性聚合物网络理论。该项目开发的自动化和标准化的图像处理和力学特性建模将在基础研究和临床中得到应用，其中非侵入性收集的组织力学特性信息将有助于工程组织的研究，患者的病变组织，以及纤维化疾病的诊断和治疗。