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bioRxiv · 10.64898/2025.12.12.694048

A multi-tiered microDicer with hierarchical blades achieves protein-preserving microdissection down to 10 microns

Arif, A.·Kumar, R.·Kwon, Y.·Rodriguez, R.·Cordts, S. C.·Koppaka, S.·Zhu, Y.·Pasa-Tolic, L.·Tang, S. K. Y.
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Abstract

To study tissue heterogeneity at the sub-millimeter scale, laser capture microdissection (LCM) has been the leading technology for isolating regions of interest (ROI) for downstream molecular profiling. As the ROI approaches cellular dimensions ([~]10 m), laser-induced photothermal damage and challenges in capturing microtissues in conventional LCM can compromise protein preservation and quantitative fidelity. This work introduces multi-tiered Dicers, fabricated by two-photon polymerization, to mechanically dissect tissue slices into uniform microtissues down to 10 m. The hierarchical blade architecture limits instantaneous blade-tissue engagement and lowers the cutting force relative to single-tier designs. For benchmarking, proteomic analysis is performed on ethanol-fixed human squamous cell carcinoma microtissues generated by Dicers and by LCM. Under identical Nanodroplet Processing in One pot for Trace Samples (nanoPOTS) and liquid chromatography-mass spectrometry (LC-MS) conditions, Dicers yield more peptides and proteins than LCM, with the largest gains at 10-20 m spatial resolution. Confocal imaging shows catapult-associated cavities in LCM-generated microtissues. This material loss, along with membrane-limited protein extraction, likely reduces protein coverage. In contrast, multi-tiered Dicers enables reproducible microdissection down to 10 m while maintaining high protein coverage. With spatial registration of microtissues under development, Dicers have potential to complement LCM for next-generation spatial proteomic workflows.

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Arif, A., Kumar, R., Kwon, Y., Rodriguez, R., Cordts, S. C., Koppaka, S., Zhu, Y., Pasa-Tolic, L., Tang, S. K. Y.. 2025-12-16. A multi-tiered microDicer with hierarchical blades achieves protein-preserving microdissection down to 10 microns. https://doi.org/10.64898/2025.12.12.694048

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