Bioengineering of Transport Across Bruch's Membrance

跨布鲁赫膜运输的生物工程

• 批准号: 6602199
• 负责人: MARK JOHNSON
• 金额: $ 27.78万
• 依托单位: NORTHWESTERN UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-05-01 至 2007-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6602199
• 关键词: basement membrane; bioengineering /biomedical engineering; biological fluid transport; choroid uvea; early diagnosis; electron microscopy; extracellular matrix; freeze etching; histopathology; human tissue; lipid transport; macular degeneration; membrane activity; membrane structure; morphometry; physical model; retinal pigment epithelium

DESCRIPTION (provided by applicant): Better understanding of the pathophysiology of the early stages of age-related maculopathy (ARM) may guide development of better treatments and/or preventions of age-related macular degeneration. Prominent clinical and histopathologic lesions of early ARM involve Bruch's membrane, a thin connective tissue between the choriocapillaris and the RPE. Unlike the case for late ARM, for which several risk factors have been identified, the only consistently identified risk factor for early ARM is advanced age. It is, therefore, important to understand how age-related changes in Bruch's membrane predispose some individuals for retinal dysfunction. A decreased transport capacity of Bruch's membrane, perhaps caused by lipid accumulation, has been postulated to be a critical early event in the pathogenesis of ARM. However, morphometric studies have not yet been successful in identifying those moieties responsible for limiting the transport capacity of Bruch's membrane. QFDE is a morphological technique that preserves extracellular matrix in exquisite detail and allows structures to be visualized that are not seen using conventional transmission electron microscopy (TEM) techniques. QFDE offers a technology that, in other connective tissues, has provided new insights into the transport characteristics of these tissues. Our goal is to combine the technique of quick-freeze/deep-etch (QFDE) morphology with bioengineering analytic methods to evaluate this hypothesis, using well-preserved eyes from normal human donors. Our specific aims are (i) to use the methods of quick-freeze/deep-etch (QFDE) morphology and lipid histochemistry in conjunction with conventional electron microscopy methods to characterize quantitatively the earliest ultrastructural changes in Bruch's membrane associated with lipid deposition in 20-70 year old donor eyes; (ii) to combine these results with analytical bioengineering tools to evaluate the effects of age-related changes on transport properties of Bruch's membrane; and (iii) to use an in vitro model of fluid and lipid transport through extracellular matrix to validate the results of the analytical studies and characterize the impact of lipid accumulation on transport.

描述（由申请人提供）：更好地了解年龄相关性黄斑病变（ARM）早期阶段的病理生理学可能会指导开发更好的治疗和/或预防年龄相关性黄斑变性的方法。早期ARM的突出临床和组织病理学病变涉及Bruch膜，一种在脉络膜毛细血管和RPE之间的薄结缔组织。与晚期ARM的情况不同，已经确定了几个风险因素，早期ARM唯一一致确定的风险因素是高龄。因此，重要的是要了解年龄相关的变化，在布鲁赫膜易患视网膜功能障碍的一些人。 一个降低的转运能力的布鲁赫的膜，可能是由脂质积累，已被假定为一个关键的早期事件的发病机制ARM. However，形态计量学研究尚未成功地确定那些负责限制布鲁赫的膜的转运能力的部分。QFDE是一种形态学技术，其以精致的细节保留细胞外基质，并允许使用常规透射电子显微镜（TEM）技术看不到的结构可视化。QFDE提供了一种技术，在其他结缔组织中，为这些组织的运输特性提供了新的见解。我们的目标是将联合收割机快速冷冻/深蚀刻（QFDE）形态学技术与生物工程分析方法相结合，使用保存完好的正常人供体眼睛来评估这一假设。 我们的具体目标是（i）使用快速冷冻/深蚀刻（QFDE）形态学和脂质组织化学的方法结合常规的电子显微镜方法来定量表征与20-70岁供体眼的脂质沉积相关的Bruch膜的早期超微结构变化;（ii）将这些结果与生物工程分析工具联合收割机结合，以评估与年龄相关的变化对布鲁赫膜转运特性的影响;和（iii）使用液体和脂质通过细胞外基质转运的体外模型来验证分析研究的结果并表征脂质积累对转运的影响。