Expansion Microscopy for the Interrogation of Nanoscale Features in Complex Biological Systems

Abstract

Super-resolution fluorescence microscopy enables researchers to directly observe details of biological systems on the nanoscale. However, current methods are often costly, require considerable skill, and necessitate the use of specialized instrumentation, all of which have limited the widespread use of super-resolution techniques. Expansion microscopy, which physically enlarges the specimen and enables ~65 nm resolution using standard confocal microscopy, is an inexpensive and easy-to-implement compliment to current super-resolution imaging modalities. Due to its low barrier of entry and ability to resolve nanoscale features with standard microscopes, it has the potential to find use in a broad range of biological research areas. Here, I discuss the development, validation, and optimization of new expansion microscopy protocols for various biological specimens including those which have previously been incompatible with this method. Additionally, I demonstrate applications in Drosophila neurobiology as well as mouse and human nephrology.