Quantifying Kidney Function with Quantum Dot Nanoprobes

描述（由申请人提供）：蛋白尿是许多原发性和继发性肾小球疾病的标志和替代标志，导致糖尿病和高血压患者发生严重肾功能障碍。为了提高与这种严重疾病相关的诊断和治疗需求，该项目旨在通过以下方式以无与伦比的精度量化体内肾小球通透性：（1）应用新一代半导体纳米晶体（CdSe/ZnS量子点）作为高度精确的尺寸标尺和非常敏感的静电纳米传感器，结合（2）最近开发的定量双-光子激发显微成像技术，使用超快近红外激光进行深层组织穿透。目前，我们能够对活体动物肾脏内的单个肾小球和管周结构进行成像。我们假设，使用这些新的量子点（QD）系统结合体内双光子显微镜将大大提高我们的成像的准确性和灵敏度，优于传统的葡聚糖探针用于肾脏研究，从而更好地了解肾小球疾病的过程，并导致早期临床试验的发展，以量化肾小球通透性。我们预测这一结果是因为量子点是刚性和球形的，并且可以以高单分散性、高光稳定性和亮度以及可调节的表面化学性质来生产。通过应用薄的生物惰性极性涂层可以实现“尺寸尺”样的准确性，而中性极性（Ser-封端）和带负电荷（Asp-封端）的肽涂覆的QD将用于产生蛋白质样的表面性质。这个跨学科项目的目标是将有关使用尖端纳米粒子探针用于生物医学应用（Naumann，Long）和最先进的光学成像（Yu，Molitoris）的专业知识联合收割机结合起来，开发出一种显着改进的成像/探针系统，用于活体肾脏成像。拟议的研究将应用这种新的成像策略，与NIH定量成像和纳米医学领域路线图中概述的主要主题高度相关，以提供对肾小球滤过屏障功能的基本了解，并深入了解肾小球损伤与蛋白尿症状发作之间的相关性。我们的研究结果将为早期诊断、提高患者护理质量和寻找未来的治疗方法提供有价值的信息。

DESCRIPTION (provided by applicant): Proteinuria is the hallmark and surrogate marker of many primary and secondary glomerular diseases resulting in serious kidney malfunctions that occur in patients with diabetes and hypertension. To enhance the diagnostic and therapeutic needs related to this serious disease, this project seeks to quantify glomerular permeability in vivo with unmatched precision by: (1) applying a new generation of semiconductor nanocrystals (CdSe/ZnS quantum dots) as highly accurate size rulers and very sensitive electrostatic nanosensors combined with (2) a recently developed quantitative two-photon excitation microscopic imaging technique that uses ultrafast near-infrared laser for deep tissue penetration. Currently, we are able to image individual glomeruli and peritubular structures inside a live animal kidney. We hypothesize that the use of these novel quantum dot (QD) systems in conjunction with in vivo two-photon microscopy will increase vastly the accuracy and sensitivity of our imaging by outperforming traditional dextran probes used in kidney studies, resulting in a better understanding of glomerular disease processes and leading to the development of early clinical tests to quantify glomerular permeability. We predict this outcome because quantum dots are rigid and spherical in shape, and can be produced with high monodispersity, high photostability and brightness as well as adjustable surface chemical properties. A "size ruler"-like accuracy can be achieved by applying thin bioinert polar coatings, whereas neutral-polar (Ser-capped) and negatively charged (Asp-capped) peptide-coated QDs will be used to create protein-like surface properties. The goal of this interdisciplinary project is to combine expertise concerning the use of cutting-edge nanoparticle probes for biomedical applications (Naumann, Long) and the state-of-the-art optical imaging (Yu, Molitoris) to develop a significantly improved and enabling imaging/probe system for intravital kidney imaging. The proposed study will apply this new imaging strategy, highly relevant to a major theme outlined in the NIH Roadmap in areas of Quantitative Imaging and Nanomedicine, to provide a basic understanding of the functions of glomerular filtration barrier and insight into the correlation between glomerular damage and the onset of proteinuric symptoms. The results of our study will offer valuable information important for early diagnosis, improving the quality of patient care, and finding a future cure.