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Living cells are out of equilibrium active materials. Cell-generated forces are transmitted across the cytoskeleton network and to the extracellular environment. These active force interactions shape cellular mechanical behavior, trigger mechano-sensing, regulate cell adaptation to the microenvironment and can affect disease outcomes. In recent years, the mechanobiology community has witnessed the emergence of many experimental and theoretical approaches to study cells as mechanically active materials. In this review, we highlight recent advancements in incorporating active characteristics of cellular behavior at different length scales into classic viscoelastic models by either adding an active tension-generating element or by adjusting the resting length of an elastic element in the model. Summarizing the two groups of approaches, we will review the formulation, and application of these models to understand cellular adaptation mechanisms in response to various types of mechanical stimuli, such as the effect of extracellular matrix properties and external loadings or deformations.
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Mechanically Triggered Hybridization Chain Reaction
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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- PAR ID:
- 10281164
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 60
- Issue:
- 36
- ISSN:
- 1433-7851
- Page Range / eLocation ID:
- p. 19974-19981
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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