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bioRxiv · 10.64898/2026.01.01.697161

Unraveling Subcellular Ultrastructure with Cyclically Multiplexed Expansion Microscopy

Gałecki, S.·Chang, B.-J.·Zhou, F. Y.·Shen, Q.·Stoddard, D.·Chen, B.·Nicastro, D.·Fiolka, R. P.·Dean, K. M.
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Abstract

Despite advances in fluorescence microscopy, spectral overlap and limited resolution hinder the dense mapping of the cellular ultrastructure. To overcome these challenges, we developed Cy-ExM, a high-plex imaging strategy that integrates optimized cryo-fixation for antigen preservation, expansion microscopy, and iterative immunofluorescence labeling. Using oblique plane microscopy, we perform three-dimensional super-resolution imaging of 20 biological targets encompassing the full cellular volume of individual mammalian cells.

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Gałecki, S., Chang, B.-J., Zhou, F. Y., Shen, Q., Stoddard, D., Chen, B., Nicastro, D., Fiolka, R. P., Dean, K. M.. 2026-01-02. Unraveling Subcellular Ultrastructure with Cyclically Multiplexed Expansion Microscopy. https://doi.org/10.64898/2026.01.01.697161

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