A New Era in Nephrology: The Role of Super-Resolution Microscopy in Research, Medical Diagnostic, and Drug Discovery.

Abstract

For decades, electron microscopy (EM) has been the primary method to visualize ultrastructural details of the kidney, including podocyte foot processes and the slit diaphragm. Despite its status as the gold standard, EM has significant limitations: it requires laborious sample preparation, works only with very small samples, is mainly qualitative, and is prone to misinterpretation due to section angle bias. Additionally, combining imaging and protein staining with antibodies poses a challenge, limiting EM's integration into routine research and diagnostic workflows. As imaging technology advances, super-resolution microscopy, with optical resolutions below 100 nm, presents a promising alternative for detailed insights into glomerular ultrastructure. This review explores various super-resolution techniques, particularly 3D-SIM, and demonstrates how they can be applied to standard histologic sections. The 3D-SIM-based measurement procedure PEMP offers a novel approach to quantifying podocyte foot process (PFP) morphology and can detect PFP changes even before proteinuria is present. Furthermore, PEMP can be combined with mRNA detection, multiplex staining, and deep learning algorithms, making it a powerful tool for kidney research, preclinical studies, and personalized diagnostics. This advancement has the potential to accelerate drug development and enhance therapeutic precision, heralding a new era of high-precision nephrology.