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bioRxiv · 10.1101/2024.02.28.582497

Expansion microscopy for super-resolution imaging of collagen-abundant tissues

Chuang, Y.-H.·Wu, Y.-F.·Lin, Y.-H.·Zhou, Y.-X.·Hsu, S.-C.·Lin, S.-J.·Chu, L.-A.
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Abstract

Expansion microscopy (ExM) is popular for three-dimensional ultrastructural imaging of cultured cells and tissue slices at nanoscale resolution with conventional microscopes via physical expansion of biological tissues. However, the application of this technology to collagen-abundant thick tissues is challenging. We demonstrate a new method, collagen expansion microscopy (ColExM), optimized for expanding tissues containing more than 70% collagen. ColExM succeeded in 4.5-fold linear expansion with minimal structural distortion of corneal and skin tissues. It was also compatible with immunostaining, allowing super-resolution visualization of three-dimensional neural structures innervating hair follicles and corneas. With ColExM, we succeeded in identifying individual mitochondria and previously unrecognized dendritic spine-like structures of corneal nerves. ColExM also enabled fine mapping of structural rearrangement of tight junctions and actin cytoskeletons. Therefore, this method can facilitate the exploration of three-dimensional nanoscale structures in collagen-rich tissues.

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Chuang, Y.-H., Wu, Y.-F., Lin, Y.-H., Zhou, Y.-X., Hsu, S.-C., Lin, S.-J., Chu, L.-A.. 2024-03-02. Expansion microscopy for super-resolution imaging of collagen-abundant tissues. https://doi.org/10.1101/2024.02.28.582497

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