Shear-Driven Solidification and Nonlinear Elasticity in Epithelial Tissues

Physical Review Letters, Год журнала: 2022, Номер 128(17)

Опубликована: Апрель 27, 2022

Biological processes, from morphogenesis to tumor invasion, spontaneously generate shear stresses inside living tissue. The mechanisms that govern the transmission of mechanical forces in epithelia and collective response tissue bulk deformations remain, however, poorly understood. Using a minimal cell-based computational model, we investigate constitutive relation confluent tissues under simple deformation. We show an initially undeformed fluidlike acquires finite rigidity above critical applied strain. This is akin shear-driven observed other soft matter systems. Interestingly, can be understood by scaling analysis vicinity second order point governs liquid-solid transition system. further solidlike responds linearly only small strains but then switches nonlinear at larger stains, with substantial stiffening. Finally, propose mean-field formulation for cells offers physical explanation

Язык: Английский

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Generating active T1 transitions through mechanochemical feedback

eLife, Год журнала: 2023, Номер 12

Опубликована: Апрель 11, 2023

Convergence–extension in embryos is controlled by chemical and mechanical signalling. A key cellular process the exchange of neighbours via T1 transitions. We propose analyse a model with positive feedback between recruitment myosin motors tension cell junctions. The produces active events, which act to elongate tissue perpendicular main direction stress. Using an idealised patch comprising several cells embedded matrix passive hexagonal cells, we identified optimal range stresses trigger event. show that directed also generate chains realistic made entirely random shapes leads convergence–extension over parameters. Our findings intercalations can stress activates events neighbouring resulting tension-dependent reorganisation, qualitative agreement experiments on gastrulation chick embryos.

Язык: Английский

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Hydrodynamics and multiscale orderin confluent epithelia

eLife, Год журнала: 2024, Номер 13

Опубликована: Янв. 8, 2024

We formulate a hydrodynamic theory of confluent epithelia: i.e. monolayers epithelial cells adhering to each other without gaps. Taking advantage recent progresses toward establishing general p-atic liquid crystals, we demonstrate that collectively migrating epithelia feature both nematic (i.e. p = 2) and hexatic 6) orders, with the former being dominant at large latter small length scales. Such remarkable multiscale crystal order leaves distinct signature in system's structure factor, which exhibits two different power-law scaling regimes, reflecting hexagonal geometry clusters uniaxial global cellular flow. support these analytical predictions cell-resolved models - self-propelled Voronoi model multiphase field highlight how momentum dissipation noise influence range fluctuations scales, thereby affecting degree cooperativity between cells. Our construction provides theoretical framework conceptualize observation layers Madin-Darby canine kidney pave way for further developments.

Язык: Английский

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Connecting Anomalous Elasticity and Sub-Arrhenius Structural Dynamics in a Cell-Based Model

Physical Review Letters, Год журнала: 2025, Номер 134(4)

Опубликована: Янв. 31, 2025

Understanding the structural dynamics of many-particle glassy systems remains a key challenge in statistical physics. Over last decade, has also been reported biological tissues, but is far from being understood. It was recently shown that vertex models dense tissue exhibit very atypical, sub-Arrhenius dynamics, and here we ask whether such atypical are related to unusual elastic properties. known at zero temperature these have an elasticity controlled by their underconstrained or isostatic nature, little about how varies with temperature. To address this question investigate 2D Voronoi model measure dependence intermediate-time plateau shear modulus bulk modulus. We find unlike conventional glass formers, moduli increase monotonically until system fluidizes. further show relaxation time can be quantitatively linked G_{p}, i.e. G_{p} modulates typical energy barrier scale for cell rearrangements. This suggests anomalous, originates its Based on our results, hypothesize might more generally give rise new class "ultrastrong" formers.

Язык: Английский

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Cell-Level Modelling of Homeostasis in Confined Epithelial Monolayers

Journal of Elasticity, Год журнала: 2025, Номер 157(2)

Опубликована: Фев. 24, 2025

Abstract Tissue homeostasis, the biological process of maintaining a steady state in tissue via control cell proliferation and death, is essential for development, growth, maintenance, proper function living organisms. Disruptions to this can lead serious diseases even death. In study, we use vertex model cell-level description mechanics investigate impact environment local mechanical properties cells on homeostasis confined epithelial tissues. We find dynamic state, where balance between divisions removals sustains characterise homeostatic terms count, area, pressure, cells’ neighbour count distribution. This work, therefore, sheds light mechanisms underlying highlights importance its control.

Язык: Английский

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Constitutive model for the rheology of biological tissue

Physical review. E, Год журнала: 2023, Номер 108(4)

Опубликована: Окт. 9, 2023

The rheology of biological tissue is key to processes such as embryo development, wound healing, and cancer metastasis. Vertex models confluent monolayers have uncovered a spontaneous liquid-solid transition tuned by cell shape; shear-induced solidification an initially liquidlike tissue. Alongside this jamming/unjamming behavior, also displays inherent viscoelasticity, with slow time rate-dependent mechanics. With motivation, we combine simulations continuum theory examine the vertex model in nonlinear shear across full range rates from quastistatic fast, elucidating its stress-strain curves after inception finite rate, steady state flow stress function strain rate. We formulate rheological constitutive that couples shape captures both solid-liquid rich linear rheology.

Язык: Английский

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Discontinuous Shear Thickening in Biological Tissue Rheology

Physical Review X, Год журнала: 2024, Номер 14(1)

Опубликована: Фев. 22, 2024

During embryonic morphogenesis, tissues undergo dramatic deformations in order to form functional organs.Similarly, adult animals, living cells and are continually subjected forces deformations.Therefore, the success of development proper maintenance physiological functions rely on ability withstand mechanical stresses as well their flow a collective manner.During these events, perturbations can originate from active processes at single cell level, competing with external exerted by surrounding organs.However, study tissue mechanics has been somewhat limited either response or intrinsic ones.In this work, we use an vertex model 2D confluent interplay that applied globally internal arise locally cellular level due motility.We elucidate particular way which between driving determines emergent properties whole.For vicinity solid-fluid jamming/unjamming transition, uncover host fascinating rheological phenomena, including yielding, shear thinning, continuous thickening (CST) discontinuous (DST).These predictions provide framework for understanding recently observed nonlinear behaviors vivo.

Язык: Английский

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Local Yield and Compliance in Active Cell Monolayers

Physical Review Letters, Год журнала: 2022, Номер 129(14)

Опубликована: Сен. 27, 2022

The rheology of biological tissue plays an important role in many processes, from organ formation to cancer invasion. Here, we use a multiphase field model motile cells simulate active microrheology within monolayer. When unperturbed, the exhibits transition between solidlike state and fluidlike tuned by cell motility deformability-the ratio energetic costs steric cell-cell repulsion cell-edge tension. perturbed, solid tissues exhibit local yield-stress behavior, with threshold force for onset motion probe particle that vanishes upon approaching solid-to-liquid transition. This is qualitatively different low high deformability regimes. At deformability, amorphous when solid, it responds compliantly deformations, smooth. monolayer more ordered translationally stiffer, appears discontinuous. Our results suggest cellular or nanoparticle transport types can be fundamentally point ways which controlled.

Язык: Английский

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The role of non-affine deformations in the elastic behavior of the cellular vertex model

Soft Matter, Год журнала: 2023, Номер 19(17), С. 3080 - 3091

Опубликована: Янв. 1, 2023

The vertex model of epithelia describes the apical surface a tissue as tiling polygonal cells, with mechanical energy governed by deviations in cell shape from preferred, or target, area, A0, and perimeter, P0. exhibits rigidity transition driven geometric incompatibility tuned target index, . For p*(6) perimeter regular hexagon unit can simultaneously attain both preferred area perimeter. As result, is mechanically soft compatible state, zero shear Young's moduli. p0 < p*(6), it geometrically impossible for any to realize simultaneously, an incompatible rigid solid state. Using mean-field approach, we present complete analytical calculation linear elastic moduli ordered model. We analyze relaxation step that includes non-affine deformations, leading softer response than previously reported. origin vanishing state presence zero-energy deformations shape. bulk modulus jump discontinuity at be lower fluid-like Poisson's ratio become negative which lowers Our work provides unified treatment elasticity demonstrates this protocol-dependent.

Язык: Английский

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Shape-Tension Coupling Produces Nematic Order in an Epithelium Vertex Model

Physical Review Letters, Год журнала: 2023, Номер 131(22)

Опубликована: Ноя. 27, 2023

We study the vertex model for epithelial tissue mechanics extended to include coupling between cell shapes and tensions in cell-cell junctions. This represents an active force which drives system out of equilibrium leads formation nematic order interspersed with prominent, long-lived +1 defects. The defects ordering are coupled shape tiling, affecting areas coordinations. intricate interplay shape, size, coordination provides a possible mechanism by tissues could spontaneously develop long-range polarity through local mechanical forces without resorting chemical patterning.

Язык: Английский

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