Quantification of fast molecular adhesion by fluorescence footprinting

Abstract

Rolling adhesion is a unique process in which the adhesion events are short-lived and operate under highly nonequilibrium conditions. These characteristics pose a challenge in molecular force quantification, where in situ measurement of these forces cannot be achieved with molecular force sensors that probe near equilibrium. Here, we demonstrated a quantitative adhesion footprint assay combining DNA-based nonequilibrium force probes and modeling to measure the molecular force involved in fast rolling adhesion. We were able to directly profile the ensemble molecular force distribution in our system during rolling adhesion with a dynamic range between 0 and 18 pN. Our results showed that the shear stress driving bead rolling motility directly controls the molecular tension on the probe-conjugated adhesion complex. Furthermore, the shear stress can steer the dissociation bias of components within the molecular force probe complex, favoring either DNA probe dissociation or receptor-ligand dissociation.

Altering Cell Junctional Tension in Spheroids through E-Cadherin Engagement Modulation

“…To align the TGTs with the force-dependent lifetime of Ecad, which is less than 0.1 s within the physiological range, we have defined the TGTs’ force thresholds as the force where the TGT lifetimes match that of Ecad–Ecad interactions . Following previously established models, , we show that the force reporting thresholds for Ecad-TGT (15 bp unzip), Ecad-TGT (20 bp unzip), and Ecad-TGT (21 bp shear) are 9.7, 11.8, and ∼62 pN, respectively (Scheme S1), and are labeled as Ecad-TGT-10, Ecad-TGT-12, and Ecad-TGT-62.…”

The effect of type-2 diabetes conditions on neutrophil rolling adhesion

“…The flow chamber construction has been reported previously [ 12 – 14 ]. Briefly, the flow chamber consisted of double-sided tape with channels cut into it sandwiched between a coverslip and a glass slide.…”

Optothermal rotation of micro-/nano-objects

“…Compared to in-plane rotation, out-of-plane rotation finds a variety of unique applications in fields such as single-cell mechanics, 3D bio-imaging, and micro-/nano-surgery. 16,[109][110][111][112][113][114][115] However, outof-plane rotation is known to be more challenging to accomplish especially for highly symmetric or isotropic targets. 116 In the past five years, a few groups have proposed diverse strategies for out-of-plane rotation under broken symmetries generated in light-driven temperature fields.…”

“…Rotation of single cells is important for the identification of cellular phenotypes, cell-cell communication, and, particularly, single-cell mechanics. 109,132 Among different measurements of single-cell mechanics, 133 cell adhesion has attracted a lot of attention as it is highly involved in many biological processes such as viral infections. However, the existing single-cell adhesion kinetics measurements can only give qualitative results since they are usually performed under conditions far away from the in situ physiological environments.…”