Three-dimensional (3D) imaging has advanced basic research and clinical medicine. However, limited resolution and imperfections of real-world 3D image material often preclude algorithmic image analysis. Here, we present a methodologic framework for such imaging and analysis for functional and spatial relations in experimental nephritis. First, optical tissue-clearing protocols were optimized to preserve fluorescence signals for light sheet fluorescence microscopy and compensated attenuation effects using adjustable 3D correction fields. Next, we adapted the fast marching algorithm to conduct backtracking in 3D environments and developed a tool to determine local concentrations of extractable objects. As a proof-of-concept application, we used this framework to determine in a glomerulonephritis model the individual proteinuria and periglomerular immune cell infiltration for all glomeruli of half a mouse kidney. A correlation between these parameters surprisingly did not support the intuitional assumption that the most inflamed glomeruli are the most proteinuric. Instead, the spatial density of adjacent glomeruli positively correlated with the proteinuria of a given glomerulus. Because proteinuric glomeruli appear clustered, this suggests that the exact location of a kidney biopsy may affect the observed severity of glomerular damage. Thus, our algorithmic pipeline described here allows analysis of various parameters of various organs composed of functional subunits, such as the kidney, and can theoretically be adapted to processing other image modalities.

中文翻译：

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通过 3 维快速行进算法确定清除的小鼠肾脏中的个体肾小球蛋白尿和肾小球周围浸润

三维（3D）成像具有先进的基础研究和临床医学。然而，有限的分辨率和现实世界 3D 图像材料的缺陷常常妨碍算法图像分析。在这里，我们提出了一种用于实验性肾炎功能和空间关系的成像和分析的方法框架。首先，优化了光学组织透明化方案，以保留用于光片荧光显微镜的荧光信号，并使用可调节的 3D 校正场补偿衰减效应。接下来，我们采用快速行进算法在 3D 环境中进行回溯，并开发了一种工具来确定可提取物体的局部浓度。作为概念验证应用，我们使用该框架在肾小球肾炎模型中确定半个小鼠肾脏的所有肾小球的个体蛋白尿和肾小球周围免疫细胞浸润。令人惊讶的是，这些参数之间的相关性并不支持炎症最严重的肾小球蛋白尿最多的直觉假设。相反，相邻肾小球的空间密度与给定肾小球的蛋白尿呈正相关。由于蛋白尿肾小球出现聚集，这表明肾活检的确切位置可能会影响观察到的肾小球损伤的严重程度。因此，我们这里描述的算法管道允许分析由功能子单元组成的各种器官（例如肾脏）的各种参数，并且理论上可以适应处理其他图像模式。