Topological action potentials in engineered tissues

Ori, H.; Duque Ramirez, M.; Hayward, R. F.; Tian, H.; Ortiz, G.; Cohen, A. E.

doi:10.1101/2022.03.16.484369

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bioRxiv · 10.1101/2022.03.16.484369

Topological action potentials in engineered tissues

Ori, H.·Duque Ramirez, M.·Hayward, R. F.·Tian, H.·Ortiz, G.·Cohen, A. E.

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Abstract

Due to the nonlinear current-voltage relations of ion channels, an interface between two tissues can have very different bioelectrical properties compared to either tissue on its own. Here we show experimentally that gap junction-coupled interfaces between non-excitable tissues can be electrically excitable. This topologically protected excitability occurs over a far larger range of ion channel expression levels than does excitability in the bulk. Topological excitations at tissue interfaces can cause local elevations in calcium concentration, possibly providing a bioelectrical mechanism for interface sensing. As in condensed matter physics, topological excitations in electrophysiology constitute a distinct class of phenomena which may show exotic and novel properties.

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Ori, H., Duque Ramirez, M., Hayward, R. F., Tian, H., Ortiz, G., Cohen, A. E.. 2022-03-18. Topological action potentials in engineered tissues. https://doi.org/10.1101/2022.03.16.484369

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