Quantitative and Multiplexed Fluorescence Lifetime Imaging of Intercellular Tensile Forces

Abstract

Mechanical interactions between cells have been shown to play critical roles in regulating cell signaling and communications.H owever,t he precise measurement of intercellular forces is still quite challenging,e specially considering the complex environment at cell-cell junctions.Inthis study,we report af luorescence lifetime-based approach to image and quantify intercellular molecular tensions.U sing this method, tensile forces among multiple ligand-receptor pairs can be measured simultaneously.W efirst validated our approach and developed lifetime measurement-based DNAtension probes to image E-cadherin-mediated tension on epithelial cells.T hese probes were then further applied to quantify the correlations between E-cadherin and N-cadherin tensions during an epithelial-mesenchymal transition process.T he modular design of these probes can potentially be used to study the mechanical features of various physiological and pathological processes.

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Recent developments in DNA-based mechanical nanodevices

“…Using epithelial-to-mesenchymal transition (EMT) as a model system, the correlation between E-cadherin- and N-cadherin-mediated tensile forces was imaged during different stages of the EMT process. 82 A larger contribution of N-cadherin tension and a reduced percentage of E-cadherin tension was observed during the EMT. The mechanical effects of different EMT inducers can also be distinguished with the help of these FLIM-MDTPs.…”

“…5A). 82 The fluorescence lifetime signal is independent of the probe concentration, and as a result, quantitative force measurement can be achieved without the use of a reference fluorophore. The FLIM-MDTP can also allow multiple ligand-receptor interactions to be studied simultaneously.…”