Zhao, YongxinBucur, OctavianIrshad, HumayunChen, FeiWeins, AstridStancu, AndreeaOh, Eun-YoungDiStasio, MarcelloTorous, VandaGlass, BenjaminStillman, IsaacSchnitt, StuartBeck, AndrewBoyden, Edward S.2018-02-262017Zhao, Y., O. Bucur, H. Irshad, F. Chen, A. Weins, A. L. Stancu, E. Oh, et al. 2017. “Nanoscale imaging of clinical specimens using pathology-optimized expansion microscopy.” Nature biotechnology 35 (8): 757-764. doi:10.1038/nbt.3892. http://dx.doi.org/10.1038/nbt.3892.http://nrs.harvard.edu/urn-3:HUL.InstRepos:34868849Expansion microscopy (ExM), a method for improving the resolution of light microscopy by physically expanding the specimen, has not been applied to clinical tissue samples. Here we report a clinically optimized form of ExM that supports nanoscale imaging of human tissue specimens that have been fixed with formalin, embedded in paraffin, stained with hematoxylin and eosin (H&E), and/or fresh frozen. The method, which we call expansion pathology (ExPath), converts clinical samples into an ExM-compatible state, then applies an ExM protocol with protein anchoring and mechanical homogenization steps optimized for clinical samples. ExPath enables ~70 nm resolution imaging of diverse biomolecules in intact tissues using conventional diffraction-limited microscopes, and standard antibody and fluorescent DNA in situ hybridization reagents. We use ExPath for optical diagnosis of kidney minimal-change disease, which previously required electron microscopy (EM), and demonstrate high-fidelity computational discrimination between early breast neoplastic lesions that to date have challenged human judgment. ExPath may enable the routine use of nanoscale imaging in pathology and clinical research.en-USJournal Article2018-02-2610.1038/nbt.3892