Cells transmit piconewton forces to receptors to mediate processes such as migration and immune recognition. A major challenge in quantifying such forces is the sparsity of cell mechanical events. Accordingly, molecular tension is typically quantified with high resolution fluorescence microscopy, which hinders widespread adoption and application. Here, we report a mechanically triggered hybridization chain reaction (mechano‐HCR) that allows chemical amplification of mechanical events. The amplification is triggered when a cell receptor mechanically denatures a duplex revealing a cryptic initiator to activate the HCR reaction in situ. Importantly, mechano‐HCR enables direct readout of pN forces using a plate reader. We leverage this capability and measured mechano‐IC50for aspirin, Y‐27632, and eptifibatide. Given that cell mechanical phenotypes are of clinical importance, mechano‐HCR may offer a convenient route for drug discovery, personalized medicine, and disease diagnosis.
Mechanics play a fundamental role in cell biology, but detecting piconewton (pN) forces is challenging because of a lack of accessible and high throughput assays. A mechanically induced catalytic amplification reaction (MCR) for readout of receptor‐mediated forces in cells is described. Mechanically labile DNA duplexes presenting ligands are surface immobilized such that specific receptor forces denature the duplex and thus expose a blocked primer. Amplification of primers is achieved using an isothermal polymerization reaction and quantified by fluorescence readout. As a proof of concept, the assay was used to test the activity of a mechanomodulatory drug and integrin adhesion receptor antibodies. To the best of our knowledge, this is the first example of a catalytic reaction triggered in response to molecular piconewton forces. The MCR may transform the field of mechanobiology by providing a new facile tool to detect receptor specific mechanics with the convenience of the polymerase chain reaction (PCR).
more » « less- NSF-PAR ID:
- 10215312
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 128
- Issue:
- 18
- ISSN:
- 0044-8249
- Page Range / eLocation ID:
- p. 5578-5582
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Cells transmit piconewton forces to receptors to mediate processes such as migration and immune recognition. A major challenge in quantifying such forces is the sparsity of cell mechanical events. Accordingly, molecular tension is typically quantified with high resolution fluorescence microscopy, which hinders widespread adoption and application. Here, we report a mechanically triggered hybridization chain reaction (mechano‐HCR) that allows chemical amplification of mechanical events. The amplification is triggered when a cell receptor mechanically denatures a duplex revealing a cryptic initiator to activate the HCR reaction in situ. Importantly, mechano‐HCR enables direct readout of pN forces using a plate reader. We leverage this capability and measured mechano‐IC50for aspirin, Y‐27632, and eptifibatide. Given that cell mechanical phenotypes are of clinical importance, mechano‐HCR may offer a convenient route for drug discovery, personalized medicine, and disease diagnosis.
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