1
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Pismen LM. Nematodynamics with odd and rotational viscosities. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2024; 47:50. [PMID: 39068304 PMCID: PMC11283408 DOI: 10.1140/epje/s10189-024-00441-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Accepted: 07/05/2024] [Indexed: 07/30/2024]
Abstract
We explore a novel mechanism of interactions between nematic order and flow including odd and rotational viscosities, and investigate activity-induced instabilities in the framework of this model. We show how these modes of viscous dissipation can be incorporated in the Ericksen-Leslie formalism, but it does not eliminate deficiencies of the approach based on Onsager's reciprocal relations that lead to spurious instabilities. The suggested way of deriving nematodynamic equations, based on a specific mechanism applicable to rigid rods, is not universal, but it avoids referring to Onsager's relations and avoids spurious instabilities in the absence of an active inputs. The model is further applied to the analysis of instabilities in active media.
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Affiliation(s)
- L M Pismen
- Department of Chemical Engineering, Technion - Israel Institute of Technology, 32000, Haifa, Israel.
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2
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Wang W, Law RA, Perez Ipiña E, Konstantopoulos K, Camley BA. Confinement, jamming, and adhesion in cancer cells dissociating from a collectively invading strand. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.28.601053. [PMID: 38979161 PMCID: PMC11230418 DOI: 10.1101/2024.06.28.601053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
When cells in a primary tumor work together to invade into nearby tissue, this can lead to cell dissociations-cancer cells breaking off from the invading front-leading to metastasis. What controls the dissociation of cells, and whether they break off singly or in small groups? Can this be determined by cell-cell adhesion or chemotactic cues given to cells? We develop a physical model for this question, based on experiments that mimic aspects of cancer cell invasion using microfluidic devices with microchannels of different widths. Experimentally, most dissociation events ("ruptures") involve single cells breaking off, but we observe some ruptures of large groups ( ∼ 20 cells) in wider channels. The rupture probability is nearly independent of channel width. We recapitulate the experimental results with a phase field cell motility model by introducing three different cell states (follower, guided, and high-motility metabolically active leader cells) based on their spatial position. These leader cells may explain why single-cell rupture is the universal most probable outcome. Our simulation results show that cell-channel adhesion is necessary for cells in narrow channels to invade, and strong cell-cell adhesion leads to fewer but larger ruptures. Chemotaxis also influences the rupture behavior: Strong chemotaxis strength leads to larger and faster ruptures. Finally, we study the relationship between biological jamming transitions and cell dissociations. Our results suggest unjamming is necessary but not sufficient to create ruptures.
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3
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Radman BA, Alhameed AMM, Shu G, Yin G, Wang M. Cellular elasticity in cancer: a review of altered biomechanical features. J Mater Chem B 2024; 12:5299-5324. [PMID: 38742281 DOI: 10.1039/d4tb00328d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
A large number of studies have shown that changes in biomechanical characteristics are an important indicator of tumor transformation in normal cells. Elastic deformation is one of the more studied biomechanical features of tumor cells, which plays an important role in tumourigenesis and development. Altered cell elasticity often brings many indications. This manuscript reviews the effects of altered cellular elasticity on cell characteristics, including adhesion viscosity, migration, proliferation, and differentiation elasticity and stiffness. Also, the physical factors that may affect cell elasticity, such as temperature, cell height, cell-viscosity, and aging, are summarized. Then, the effects of cell-matrix, cytoskeleton, in vitro culture medium, and cell-substrate with different three-dimensional structures on cell elasticity during cell tumorigenesis are outlined. Importantly, we summarize the current signaling pathways that may affect cellular elasticity, as well as tests for cellular elastic deformation. Finally, we summarize current hybrid materials: polymer-polymer, protein-protein, and protein-polymer hybrids, also, nano-delivery strategies that target cellular resilience and cases that are at least in clinical phase 1 trials. Overall, the behavior of cancer cell elasticity is modulated by biological, chemical, and physical changes, which in turn have the potential to alter cellular elasticity, and this may be an encouraging prediction for the future discovery of cancer therapies.
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Affiliation(s)
- Bakeel A Radman
- Department of Pathology, Xiangya Hospital, School of Basic Medical Sciences, Central South University, Changsha, China.
- Department of Biology, College of Science and Education, Albaydha University, Yemen
| | | | - Guang Shu
- Department of Histology and Embryology, School of Basic Medical Sciences, Central South University, Changsha, 410013, China
- China-Africa Research Center of Infectious Diseases, School of Basic Medical Sciences, Central South University, Changsha, 410013, China
| | - Gang Yin
- Department of Pathology, Xiangya Hospital, School of Basic Medical Sciences, Central South University, Changsha, China.
| | - Maonan Wang
- Department of Pathology, Xiangya Hospital, School of Basic Medical Sciences, Central South University, Changsha, China.
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4
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Monfared S, Ravichandran G, Andrade JE, Doostmohammadi A. Short-range correlation of stress chains near solid-to-liquid transition in active monolayers. J R Soc Interface 2024; 21:20240022. [PMID: 38715321 PMCID: PMC11077009 DOI: 10.1098/rsif.2024.0022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 02/28/2024] [Accepted: 03/08/2024] [Indexed: 05/12/2024] Open
Abstract
Using a three-dimensional model of cell monolayers, we study the spatial organization of active stress chains as the monolayer transitions from a solid to a liquid state. The critical exponents that characterize this transition map the isotropic stress percolation onto the two-dimensional random percolation universality class, suggesting short-range stress correlations near this transition. This mapping is achieved via two distinct, independent pathways: (i) cell-cell adhesion and (ii) active traction forces. We unify our findings by linking the nature of this transition to high-stress fluctuations, distinctly linked to each pathway. The results elevate the importance of the transmission of mechanical information in dense active matter and provide a new context for understanding the non-equilibrium statistical physics of phase transition in active systems.
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Affiliation(s)
- Siavash Monfared
- Niels Bohr Institute, University of Copenhagen, Kobenhavn, 2100, Denmark
| | - Guruswami Ravichandran
- Division of Engineering and Applied Science, California Institute of Technology, , CA, 91125, USA
| | - José E. Andrade
- Division of Engineering and Applied Science, California Institute of Technology, , CA, 91125, USA
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5
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Sarkar T, Krajnc M. Graph topological transformations in space-filling cell aggregates. PLoS Comput Biol 2024; 20:e1012089. [PMID: 38743660 PMCID: PMC11093388 DOI: 10.1371/journal.pcbi.1012089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Accepted: 04/19/2024] [Indexed: 05/16/2024] Open
Abstract
Cell rearrangements are fundamental mechanisms driving large-scale deformations of living tissues. In three-dimensional (3D) space-filling cell aggregates, cells rearrange through local topological transitions of the network of cell-cell interfaces, which is most conveniently described by the vertex model. Since these transitions are not yet mathematically properly formulated, the 3D vertex model is generally difficult to implement. The few existing implementations rely on highly customized and complex software-engineering solutions, which cannot be transparently delineated and are thus mostly non-reproducible. To solve this outstanding problem, we propose a reformulation of the vertex model. Our approach, called Graph Vertex Model (GVM), is based on storing the topology of the cell network into a knowledge graph with a particular data structure that allows performing cell-rearrangement events by simple graph transformations. Importantly, when these same transformations are applied to a two-dimensional (2D) polygonal cell aggregate, they reduce to a well-known T1 transition, thereby generalizing cell-rearrangements in 2D and 3D space-filling packings. This result suggests that the GVM's graph data structure may be the most natural representation of cell aggregates and tissues. We also develop a Python package that implements GVM, relying on a graph-database-management framework Neo4j. We use this package to characterize an order-disorder transition in 3D cell aggregates, driven by active noise and we find aggregates undergoing efficient ordering close to the transition point. In all, our work showcases knowledge graphs as particularly suitable data models for structured storage, analysis, and manipulation of tissue data.
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Affiliation(s)
- Tanmoy Sarkar
- Department of Theoretical Physics, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Matej Krajnc
- Department of Theoretical Physics, Jožef Stefan Institute, Ljubljana, Slovenia
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6
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Graham JN, Zhang G, Yeomans JM. Cell sorting by active forces in a phase-field model of cell monolayers. SOFT MATTER 2024; 20:2955-2960. [PMID: 38469688 DOI: 10.1039/d3sm01033c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Cell sorting, the segregation of cells with different properties into distinct domains, is a key phenomenon in biological processes such as embryogenesis. We use a phase-field model of a confluent cell layer to study the role of activity in cell sorting. We find that a mixture of cells with extensile or contractile dipolar activity, and which are identical apart from their activity, quickly sort into small, elongated patches which then grow slowly in time. We interpret the sorting as driven by the different diffusivity of the extensile and contractile cells, mirroring the ordering of Brownian particles connected to different hot and cold thermostats. We check that the free energy is not changed by either partial or complete sorting, thus confirming that activity can be responsible for the ordering even in the absence of thermodynamic mechanisms.
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Affiliation(s)
- James N Graham
- Rudolf Peierls Centre for Theoretical Physics, Parks Road, University of Oxford, Oxford, OX1 3PU, UK.
| | - Guanming Zhang
- Center for Soft Matter Research, Department of Physics, New York University, New York 10003, USA
- Simons Center for Computational Physical Chemistry, Department of Chemistry, New York University, New York 10003, USA
| | - Julia M Yeomans
- Rudolf Peierls Centre for Theoretical Physics, Parks Road, University of Oxford, Oxford, OX1 3PU, UK.
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7
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Happel L, Voigt A. Coordinated Motion of Epithelial Layers on Curved Surfaces. PHYSICAL REVIEW LETTERS 2024; 132:078401. [PMID: 38427891 DOI: 10.1103/physrevlett.132.078401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 12/21/2023] [Indexed: 03/03/2024]
Abstract
Coordinated cellular movements are key processes in tissue morphogenesis. Using a cell-based modeling approach we study the dynamics of epithelial layers lining surfaces with constant and varying curvature. We demonstrate that extrinsic curvature effects can explain the alignment of cell elongation with the principal directions of curvature. Together with specific self-propulsion mechanisms and cell-cell interactions this effect gets enhanced and can explain observed large-scale, persistent, and circumferential rotation on cylindrical surfaces. On toroidal surfaces the resulting curvature coupling is an interplay of intrinsic and extrinsic curvature effects. These findings unveil the role of curvature and postulate its importance for tissue morphogenesis.
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Affiliation(s)
- L Happel
- Institute of Scientific Computing, TU Dresden, 01062 Dresden, Germany
| | - A Voigt
- Institute of Scientific Computing, TU Dresden, 01062 Dresden, Germany
- Center for Systems Biology Dresden, Pfotenhauerstr. 108, 01307 Dresden, Germany
- Cluster of Excellence, Physics of Life, TU Dresden, Arnoldstr. 18, 01307 Dresden, Germany
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张 德, 张 豪, 李 博. [The Dynamic Model of the Active-Inactive Cell Interface]. SICHUAN DA XUE XUE BAO. YI XUE BAN = JOURNAL OF SICHUAN UNIVERSITY. MEDICAL SCIENCE EDITION 2024; 55:39-46. [PMID: 38322532 PMCID: PMC10839493 DOI: 10.12182/20240160508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2023] [Indexed: 02/08/2024]
Abstract
Objective To explore the morphodynamics of the active-inactive cell monolayer interfaces by using the active liquid crystal model. Methods A continuum mechanical model was established based on the active liquid crystal theory and the active-inactive cell monolayer interfaces were established by setting the activity difference of cell monolayers. The theoretical equations were solved numerically by the finite difference and the lattice Boltzmann method. Results The active-inactive cell interfaces displayed three typical morphologies, namely, flat interface, wavy interface, and finger-like interface. On the flat interfaces, the cells were oriented perpendicular to the interface, the -1/2 topological defects were clustered in the interfaces, and the interfaces were negatively charged. On the wavy interfaces, cells showed no obvious preference for orientation at the interfaces and the interfaces were neutrally charged. On the finger-like interfaces, cells were tangentially oriented at the interfaces, the +1/2 topological defects were collected at the interfaces, driving the growth of the finger-like structures, and the interfaces were positively charged. Conclusion The orientation of the cell alignment at the interface can significantly affect the morphologies of the active-inactive cell monolayer interfaces, which is closely associated with the dynamics of topological defects at the interfaces.
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Affiliation(s)
- 德清 张
- 清华大学工程力学系 生物力学与医学工程研究所 (北京 100084)Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - 豪舜 张
- 清华大学工程力学系 生物力学与医学工程研究所 (北京 100084)Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
| | - 博 李
- 清华大学工程力学系 生物力学与医学工程研究所 (北京 100084)Institute of Biomechanics and Medical Engineering, Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
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9
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Armengol-Collado JM, Carenza LN, Giomi L. Hydrodynamics and multiscale order in confluent epithelia. eLife 2024; 13:e86400. [PMID: 38189410 PMCID: PMC10963026 DOI: 10.7554/elife.86400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2023] [Accepted: 01/05/2024] [Indexed: 01/09/2024] Open
Abstract
We formulate a hydrodynamic theory of confluent epithelia: i.e. monolayers of epithelial cells adhering to each other without gaps. Taking advantage of recent progresses toward establishing a general hydrodynamic theory of p-atic liquid crystals, we demonstrate that collectively migrating epithelia feature both nematic (i.e. p = 2) and hexatic (i.e. p = 6) orders, with the former being dominant at large and the latter at small length scales. Such a remarkable multiscale liquid crystal order leaves a distinct signature in the system's structure factor, which exhibits two different power-law scaling regimes, reflecting both the hexagonal geometry of small cells clusters and the uniaxial structure of the global cellular flow. We support these analytical predictions with two different cell-resolved models of epithelia - i.e. the self-propelled Voronoi model and the multiphase field model - and highlight how momentum dissipation and noise influence the range of fluctuations at small length scales, thereby affecting the degree of cooperativity between cells. Our construction provides a theoretical framework to conceptualize the recent observation of multiscale order in layers of Madin-Darby canine kidney cells and pave the way for further theoretical developments.
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Affiliation(s)
| | | | - Luca Giomi
- Instituut-Lorentz, Leiden UniversityLeidenNetherlands
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10
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Zhang Y, Fodor É. Pulsating Active Matter. PHYSICAL REVIEW LETTERS 2023; 131:238302. [PMID: 38134789 DOI: 10.1103/physrevlett.131.238302] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 07/18/2023] [Accepted: 11/13/2023] [Indexed: 12/24/2023]
Abstract
We reveal that the mechanical pulsation of locally synchronized particles is a generic route to propagate deformation waves. We consider a model of dense repulsive particles whose activity drives periodic change in size of each individual. The dynamics is inspired by biological tissues where cells consume fuel to sustain active deformation. We show that the competition between repulsion and synchronization triggers an instability which promotes a wealth of dynamical patterns, ranging from spiral waves to defect turbulence. We identify the mechanisms underlying the emergence of patterns, and characterize the corresponding transitions. By coarse-graining the dynamics, we propose a hydrodynamic description of an assembly of pulsating particles, and discuss an analogy with reaction-diffusion systems.
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Affiliation(s)
- Yiwei Zhang
- Department of Physics and Materials Science, University of Luxembourg, L-1511 Luxembourg, Luxembourg
| | - Étienne Fodor
- Department of Physics and Materials Science, University of Luxembourg, L-1511 Luxembourg, Luxembourg
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11
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Ioratim-Uba A, Liverpool TB, Henkes S. Mechanochemical Active Feedback Generates Convergence Extension in Epithelial Tissue. PHYSICAL REVIEW LETTERS 2023; 131:238301. [PMID: 38134807 DOI: 10.1103/physrevlett.131.238301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 11/07/2023] [Indexed: 12/24/2023]
Abstract
Convergence extension, the simultaneous elongation of tissue along one axis while narrowing along a perpendicular axis, occurs during embryonic development. A fundamental process that contributes to shaping the organism, it happens in many different species and tissue types. Here, we present a minimal continuum model, that can be directly linked to the controlling microscopic biochemistry, which shows spontaneous convergence extension. It is comprised of a 2D viscoelastic active material with a mechanochemical active feedback mechanism coupled to a substrate via friction. Robust convergent extension behavior emerges beyond a critical value of the activity parameter and is controlled by the boundary conditions and the coupling to the substrate. Oscillations and spatial patterns emerge in this model when internal dissipation dominates over friction, as well as in the active elastic limit.
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Affiliation(s)
| | | | - Silke Henkes
- School of Mathematics, University of Bristol, Bristol BS8 1UG, United Kingdom
- Lorentz Institute for Theoretical Physics, Leiden University, Leiden 2333 CA, The Netherlands
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12
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Mori F, Bhattacharyya S, Yeomans JM, Thampi SP. Viscoelastic confinement induces periodic flow reversals in active nematics. Phys Rev E 2023; 108:064611. [PMID: 38243430 DOI: 10.1103/physreve.108.064611] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Accepted: 11/22/2023] [Indexed: 01/21/2024]
Abstract
We use linear stability analysis and hybrid lattice Boltzmann simulations to study the dynamical behavior of an active nematic confined in a channel made of viscoelastic material. We find that the quiescent, ordered active nematic is unstable above a critical activity. The transition is to a steady flow state for high elasticity of the channel surroundings. However, below a threshold elastic modulus, the system produces spontaneous oscillations with periodic flow reversals. We provide a phase diagram that highlights the region where time-periodic oscillations are observed and explain how they are produced by the interplay of activity and viscoelasticity. Our results suggest experiments to study the role of viscoelastic confinement in the spatiotemporal organization and control of active matter.
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Affiliation(s)
- Francesco Mori
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Saraswat Bhattacharyya
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Julia M Yeomans
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Sumesh P Thampi
- Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai-36, India
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13
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Rozman J, Yeomans JM, Sknepnek R. Shape-Tension Coupling Produces Nematic Order in an Epithelium Vertex Model. PHYSICAL REVIEW LETTERS 2023; 131:228301. [PMID: 38101347 DOI: 10.1103/physrevlett.131.228301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 06/26/2023] [Accepted: 10/20/2023] [Indexed: 12/17/2023]
Abstract
We study the vertex model for epithelial tissue mechanics extended to include coupling between the cell shapes and tensions in cell-cell junctions. This coupling represents an active force which drives the system out of equilibrium and leads to the formation of nematic order interspersed with prominent, long-lived +1 defects. The defects in the nematic ordering are coupled to the shape of the cell tiling, affecting cell areas and coordinations. This intricate interplay between cell shape, size, and coordination provides a possible mechanism by which tissues could spontaneously develop long-range polarity through local mechanical forces without resorting to long-range chemical patterning.
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Affiliation(s)
- Jan Rozman
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Julia M Yeomans
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - Rastko Sknepnek
- School of Science and Engineering, University of Dundee, Dundee DD1 4HN, United Kingdom
- School of Life Sciences, University of Dundee, Dundee DD1 5EH, United Kingdom
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14
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Yang S, Palmquist KH, Nathan L, Pfeifer CR, Schultheiss PJ, Sharma A, Kam LC, Miller PW, Shyer AE, Rodrigues AR. Morphogens enable interacting supracellular phases that generate organ architecture. Science 2023; 382:eadg5579. [PMID: 37995219 DOI: 10.1126/science.adg5579] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Accepted: 09/27/2023] [Indexed: 11/25/2023]
Abstract
During vertebrate organogenesis, increases in morphological complexity are tightly coupled to morphogen expression. In this work, we studied how morphogens influence self-organizing processes at the collective or "supra"-cellular scale in avian skin. We made physical measurements across length scales, which revealed morphogen-enabled material property differences that were amplified at supracellular scales in comparison to cellular scales. At the supracellular scale, we found that fibroblast growth factor (FGF) promoted "solidification" of tissues, whereas bone morphogenetic protein (BMP) promoted fluidity and enhanced mechanical activity. Together, these effects created basement membrane-less compartments within mesenchymal tissue that were mechanically primed to drive avian skin tissue budding. Understanding this multiscale process requires the ability to distinguish between proximal effects of morphogens that occur at the cellular scale and their functional effects, which emerge at the supracellular scale.
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Affiliation(s)
- Sichen Yang
- Laboratory of Morphogenesis, The Rockefeller University, New York, NY 10065, USA
| | - Karl H Palmquist
- Laboratory of Morphogenesis, The Rockefeller University, New York, NY 10065, USA
| | - Levy Nathan
- Laboratory of Morphogenesis, The Rockefeller University, New York, NY 10065, USA
| | - Charlotte R Pfeifer
- Laboratory of Morphogenesis, The Rockefeller University, New York, NY 10065, USA
| | - Paula J Schultheiss
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
- Department of Medicine, Columbia University, New York, NY 10032, USA
| | - Anurag Sharma
- Electron Microscopy Resource Center, The Rockefeller University, New York, NY 10065, USA
| | - Lance C Kam
- Department of Biomedical Engineering, Columbia University, New York, NY 10027, USA
- Department of Medicine, Columbia University, New York, NY 10032, USA
| | - Pearson W Miller
- Center for Computational Biology, Flatiron Institute, New York, NY 10010, USA
| | - Amy E Shyer
- Laboratory of Morphogenesis, The Rockefeller University, New York, NY 10065, USA
| | - Alan R Rodrigues
- Laboratory of Morphogenesis, The Rockefeller University, New York, NY 10065, USA
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15
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Maleki F, Najafi A. Instabilities in a growing system of active particles: scalar and vectorial systems. SOFT MATTER 2023; 19:8157-8163. [PMID: 37850327 DOI: 10.1039/d3sm00880k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2023]
Abstract
The physics of micron-scale biological colonies usually benefits from different out-of-equilibrium sources. In bacterial colonies and cellular tissues, the growth process is among the important active sources that determine the dynamics. In this article, we study the generic dynamical instabilities associated with the growth phenomena that may arise in both scalar and vectorial systems. In vectorial systems, where the rotational degrees of particles play a role, a phenomenological growth-mediated torque can affect the rotational dynamics of individual particles. We show that such a growth-mediated torque can result in active traveling waves in the bulk of a growing system. In addition to the bulk properties, we analyze the instabilities in the shape of growing interfaces in both scalar and vectorial systems.
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Affiliation(s)
- Forouh Maleki
- Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
| | - Ali Najafi
- Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran
- Research Center for Basic Sciences & Modern Technologies (RBST), Institute for Advanced Studies in Basic Sciences, Zanjan, Iran.
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16
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Hopkins A, Loewe B, Chiang M, Marenduzzo D, Marchetti MC. Motility induced phase separation of deformable cells. SOFT MATTER 2023; 19:8172-8178. [PMID: 37850477 DOI: 10.1039/d3sm01059g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2023]
Abstract
Using a multi-phase field model, we examine how particle deformability, which is a proxy for cell stiffness, affects motility induced phase separation (MIPS). We show that purely repulsive deformable, i.e., squishy, cells phase separate more effectively than their rigid counterparts. This can be understood as due to the fact that deformability increases the effective duration of collisions. In addition, the dense regions become increasingly disordered as deformability increases. Our results contextualize the applicability of MIPS to biological systems and have implications for how cells in biological systems may self-organize.
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Affiliation(s)
- Austin Hopkins
- Department of Physics, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
| | - Benjamin Loewe
- School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, UK
| | - Michael Chiang
- School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, UK
| | - Davide Marenduzzo
- School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, UK
| | - M Cristina Marchetti
- Department of Physics, University of California Santa Barbara, Santa Barbara, CA 93106, USA.
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17
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Hadjifrangiskou I, Ruske LJ, Yeomans JM. Active nematics with deformable particles. SOFT MATTER 2023; 19:6664-6670. [PMID: 37609906 DOI: 10.1039/d3sm00627a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
The hydrodynamic theory of active nematics has been often used to describe the spatio-temporal dynamics of cell flows and motile topological defects within soft confluent tissues. Those theories, however, often rely on the assumption that tissues consist of cells with a fixed, anisotropic shape and do not resolve dynamical cell shape changes due to flow gradients. In this paper we extend the continuum theory of active nematics to include cell shape deformability. We find that circular cells in tissues must generate sufficient active stress to overcome an elastic barrier to deforming their shape in order to drive tissue-scale flows. Above this threshold the systems enter a dynamical steady-state with regions of elongated cells and strong flows coexisting with quiescent regions of isotropic cells.
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Affiliation(s)
- Ioannis Hadjifrangiskou
- The Rudolf Peierls Centre for Theoretical Physics, Beecroft Building, Parks Road, Oxford, OX1 3PU, UK.
| | - Liam J Ruske
- The Rudolf Peierls Centre for Theoretical Physics, Beecroft Building, Parks Road, Oxford, OX1 3PU, UK.
| | - Julia M Yeomans
- The Rudolf Peierls Centre for Theoretical Physics, Beecroft Building, Parks Road, Oxford, OX1 3PU, UK.
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18
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Jain HP, Voigt A, Angheluta L. Robust statistical properties of T1 transitions in a multi-phase field model of cell monolayers. Sci Rep 2023; 13:10096. [PMID: 37344548 DOI: 10.1038/s41598-023-37064-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 06/15/2023] [Indexed: 06/23/2023] Open
Abstract
Large-scale tissue deformation which is fundamental to tissue development hinges on local cellular rearrangements, such as T1 transitions. In the realm of the multi-phase field model, we analyse the statistical and dynamical properties of T1 transitions in a confluent monolayer. We identify an energy profile that is robust to changes in several model parameters. It is characterized by an asymmetric profile with a fast increase in energy before the T1 transition and a sudden drop after the T1 transition, followed by a slow relaxation. The latter being a signature of the fluidity of the cell monolayer. We show that T1 transitions are sources of localised large deformation of the cells undergoing the neighbour exchange, and they induce other T1 transitions in the nearby cells leading to a chaining of events that propagate local cell deformation to large scale tissue flows.
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Affiliation(s)
- Harish P Jain
- Njord Centre, Department of Physics, University of Oslo, 0371, Oslo, Norway.
| | - Axel Voigt
- Institute of Scientific Computing, Technische Universität Dresden, 01062, Dresden, Germany
- Center of Systems Biology Dresden, Pfotenhauerstr. 108, 01307, Dresden, Germany
- Cluster of Excellence - Physics of Life, TU Dresden, 01062, Dresden, Germany
| | - Luiza Angheluta
- Njord Centre, Department of Physics, University of Oslo, 0371, Oslo, Norway
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19
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Dow LP, Parmar T, Marchetti MC, Pruitt BL. Engineering tools for quantifying and manipulating forces in epithelia. BIOPHYSICS REVIEWS 2023; 4:021303. [PMID: 38510344 PMCID: PMC10903508 DOI: 10.1063/5.0142537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 04/20/2023] [Indexed: 03/22/2024]
Abstract
The integrity of epithelia is maintained within dynamic mechanical environments during tissue development and homeostasis. Understanding how epithelial cells mechanosignal and respond collectively or individually is critical to providing insight into developmental and (patho)physiological processes. Yet, inferring or mimicking mechanical forces and downstream mechanical signaling as they occur in epithelia presents unique challenges. A variety of in vitro approaches have been used to dissect the role of mechanics in regulating epithelia organization. Here, we review approaches and results from research into how epithelial cells communicate through mechanical cues to maintain tissue organization and integrity. We summarize the unique advantages and disadvantages of various reduced-order model systems to guide researchers in choosing appropriate experimental systems. These model systems include 3D, 2D, and 1D micromanipulation methods, single cell studies, and noninvasive force inference and measurement techniques. We also highlight a number of in silico biophysical models that are informed by in vitro and in vivo observations. Together, a combination of theoretical and experimental models will aid future experiment designs and provide predictive insight into mechanically driven behaviors of epithelial dynamics.
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Affiliation(s)
| | - Toshi Parmar
- Department of Physics, University of California Santa Barbara, Santa Barbara, California 93106, USA
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20
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Monfared S, Ravichandran G, Andrade J, Doostmohammadi A. Mechanical basis and topological routes to cell elimination. eLife 2023; 12:82435. [PMID: 37070647 PMCID: PMC10112887 DOI: 10.7554/elife.82435] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 03/22/2023] [Indexed: 04/19/2023] Open
Abstract
Cell layers eliminate unwanted cells through the extrusion process, which underlines healthy versus flawed tissue behaviors. Although several biochemical pathways have been identified, the underlying mechanical basis including the forces involved in cellular extrusion remains largely unexplored. Utilizing a phase-field model of a three-dimensional cell layer, we study the interplay of cell extrusion with cell-cell and cell-substrate interactions in a flat monolayer. Independent tuning of cell-cell versus cell-substrate adhesion forces reveals that extrusion events can be distinctly linked to defects in nematic and hexatic orders associated with cellular arrangements. Specifically, we show that by increasing relative cell-cell adhesion forces the cell monolayer can switch between the collective tendency towards fivefold, hexatic, disclinations relative to half-integer, nematic, defects for extruding a cell. We unify our findings by accessing three-dimensional mechanical stress fields to show that an extrusion event acts as a mechanism to relieve localized stress concentration.
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Affiliation(s)
- Siavash Monfared
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, United States
| | - Guruswami Ravichandran
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, United States
| | - José Andrade
- Division of Engineering and Applied Science, California Institute of Technology, Pasadena, United States
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21
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Selvamani P, Chelakkot R, Nandi A, Inamdar MM. Emergence of Spatial Scales and Macroscopic Tissue Dynamics in Active Epithelial Monolayers. Cells Tissues Organs 2023; 213:269-282. [PMID: 37044075 DOI: 10.1159/000528501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Accepted: 11/22/2022] [Indexed: 04/14/2023] Open
Abstract
Migrating cells in tissues are often known to exhibit collective swirling movements. In this paper, we develop an active vertex model with polarity dynamics based on contact inhibition of locomotion (CIL). We show that under this dynamics, the cells form steady-state vortices in velocity, polarity, and cell stress with length scales that depend on polarity alignment rate (ζ), self-motility (v0), and cell-cell bond tension (λ). When the ratio λ/v0 becomes larger, the tissue reaches a near jamming state because of the inability of the cells to exchange their neighbors, and the length scale associated with tissue kinematics increases. A deeper examination of this jammed state provides insights into the mechanism of sustained swirl formation under CIL rule that is governed by the feedback between cell polarities and deformations. To gain additional understanding of how active forcing governed by CIL dynamics leads to large-scale tissue dynamics, we systematically coarse-grain cell stress, polarity, and motility and show that the tissue remains polar even on larger length scales. Overall, we explore the origin of swirling patterns during collective cell migration and obtain a connection between cell-level dynamics and large-scale cellular flow patterns observed in epithelial monolayers.
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Affiliation(s)
- Padmalochini Selvamani
- Center for Research in Nanotechnology and Science, Indian Institute of Technology Bombay, Mumbai, India
| | | | - Amitabha Nandi
- Department of Physics, Indian Institute of Technology Bombay, Mumbai, India
| | - Mandar M Inamdar
- Department of Civil Engineering, Indian Institute of Technology Bombay, Mumbai, India
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22
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Kuang X, Guan G, Tang C, Zhang L. MorphoSim: an efficient and scalable phase-field framework for accurately simulating multicellular morphologies. NPJ Syst Biol Appl 2023; 9:6. [PMID: 36806172 PMCID: PMC9938209 DOI: 10.1038/s41540-023-00265-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Accepted: 01/04/2023] [Indexed: 02/19/2023] Open
Abstract
The phase field model can accurately simulate the evolution of microstructures with complex morphologies, and it has been widely used for cell modeling in the last two decades. However, compared to other cellular models such as the coarse-grained model and the vertex model, its high computational cost caused by three-dimensional spatial discretization hampered its application and scalability, especially for multicellular organisms. Recently, we built a phase field model coupled with in vivo imaging data to accurately reconstruct the embryonic morphogenesis of Caenorhabditis elegans from 1- to 8-cell stages. In this work, we propose an improved phase field model by using the stabilized numerical scheme and modified volume constriction. Then we present a scalable phase-field framework, MorphoSim, which is 100 times more efficient than the previous one and can simulate over 100 mechanically interacting cells. Finally, we demonstrate how MorphoSim can be successfully applied to reproduce the assembly, self-repairing, and dissociation of a synthetic artificial multicellular system - the synNotch system.
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Affiliation(s)
- Xiangyu Kuang
- Center for Quantitative Biology, Peking University, Beijing, 100871, China
| | - Guoye Guan
- Center for Quantitative Biology, Peking University, Beijing, 100871, China
| | - Chao Tang
- Center for Quantitative Biology, Peking University, Beijing, 100871, China.
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
- School of Physics, Peking University, Beijing, 100871, China.
| | - Lei Zhang
- Center for Quantitative Biology, Peking University, Beijing, 100871, China.
- Beijing International Center for Mathematical Research, Peking University, Beijing, 100871, China.
- Center for Machine Learning Research, Peking University, Beijing, 100871, China.
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23
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Lin SZ, Merkel M, Rupprecht JF. Structure and Rheology in Vertex Models under Cell-Shape-Dependent Active Stresses. PHYSICAL REVIEW LETTERS 2023; 130:058202. [PMID: 36800465 DOI: 10.1103/physrevlett.130.058202] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 08/19/2022] [Accepted: 01/04/2023] [Indexed: 06/18/2023]
Abstract
Biological cells can actively tune their intracellular architecture according to their overall shape. Here we explore the rheological implication of such coupling in a minimal model of a dense cellular material where each cell exerts an active mechanical stress along its axis of elongation. Increasing the active stress amplitude leads to several transitions. An initially hexagonal crystal motif is first destabilized into a solid with anisotropic cells whose shear modulus eventually vanishes at a first critical activity. Increasing activity beyond this first critical value, we find a re-entrant transition to a regime with finite hexatic order and finite shear modulus, in which cells arrange according to a rhombile pattern with periodically arranged rosette structures. The shear modulus vanishes again at a third threshold beyond which spontaneous tissue flows and topological defects of the nematic cell shape field arise. Flow and stress fields around the defects agree with active nematic theory, with either contractile or extensile signs, as also observed in several epithelial tissue experiments.
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Affiliation(s)
- Shao-Zhen Lin
- Aix Marseille Université, Université de Toulon, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, Marseille, France
| | - Matthias Merkel
- Aix Marseille Université, Université de Toulon, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, Marseille, France
| | - Jean-François Rupprecht
- Aix Marseille Université, Université de Toulon, CNRS, Centre de Physique Théorique, Turing Center for Living Systems, Marseille, France
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24
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Noordstra I, Morris RG, Yap AS. Cadherins and the cortex: A matter of time? Curr Opin Cell Biol 2023; 80:102154. [PMID: 36822056 DOI: 10.1016/j.ceb.2023.102154] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 01/16/2023] [Accepted: 01/18/2023] [Indexed: 02/23/2023]
Abstract
Cell adhesion systems commonly operate in close partnership with the cytoskeleton. Adhesion receptors bind to the cortex and regulate its dynamics, organization and mechanics; conversely, the cytoskeleton influences aspects of adhesion, including strength, stability and ductility. In this review we consider recent advances in elucidating such cooperation, focusing on interactions between classical cadherins and actomyosin. The evidence presents an apparent paradox. Molecular mechanisms of mechanosensation by the cadherin-actin apparatus imply that adhesion strengthens under tension. However, this does not always translate to the broader setting of confluent tissues, where increases in fluctuations of tension can promote intercalation due to the shrinkage of adherens junctions. Emerging evidence suggests that understanding of timescales may be important in resolving this issue, but that further work is needed to understand the role of adhesive strengthening across scales.
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Affiliation(s)
- Ivar Noordstra
- Centre for Cell Biology of Chronic Disease, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Brisbane, Queensland, 4072 Australia
| | - Richard G Morris
- School of Physics, Sydney, NSW 2052, Australia; EMBL Australia Node in Single Molecule Science, School of Medical Sciences, University of New South Wales, Sydney, NSW 2052, Australia.
| | - Alpha S Yap
- Centre for Cell Biology of Chronic Disease, Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Brisbane, Queensland, 4072 Australia.
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25
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Ruske LJ, Yeomans JM. Activity-driven tissue alignment in proliferating spheroids. SOFT MATTER 2023; 19:921-931. [PMID: 36625444 DOI: 10.1039/d2sm01239a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
We extend the continuum theory of active nematic fluids to study cell flows and tissue dynamics inside multicellular spheroids, spherical, self-assembled aggregates of cells that are widely used as model systems to study tumour dynamics. Cells near the surface of spheroids have better access to nutrients and therefore proliferate more rapidly than those in the resource-depleted core. Using both analytical arguments and three-dimensional simulations, we find that the proliferation gradients result in flows and in gradients of activity both of which can align the orientation axis of cells inside the aggregates. Depending on environmental conditions and the intrinsic tissue properties, we identify three distinct alignment regimes: spheroids in which all the cells align either radially or tangentially to the surface throughout the aggregate and spheroids with angular cell orientation close to the surface and radial alignment in the core. The continuum description of tissue dynamics inside spheroids not only allows us to infer dynamic cell parameters from experimentally measured cell alignment profiles, but more generally motivates novel mechanisms for controlling the alignment of cells within aggregates which has been shown to influence the mechanical properties and invasive capabilities of tumors.
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Affiliation(s)
- Liam J Ruske
- Rudolf Peierls Centre For Theoretical Physics, University of Oxford, UK.
| | - Julia M Yeomans
- Rudolf Peierls Centre For Theoretical Physics, University of Oxford, UK.
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26
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Rønning J, Marchetti MC, Angheluta L. Defect self-propulsion in active nematic films with spatially varying activity. ROYAL SOCIETY OPEN SCIENCE 2023; 10:221229. [PMID: 36816847 PMCID: PMC9929493 DOI: 10.1098/rsos.221229] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
We study the dynamics of topological defects in active nematic films with spatially varying activity and consider two set-ups: (i) a constant activity gradient and (ii) a sharp jump in activity. A constant gradient of extensile (contractile) activity endows the comet-like +1/2 defect with a finite vorticity that drives the defect to align its nose in the direction of decreasing (increasing) gradient. A constant gradient does not, however, affect the known self-propulsion of the +1/2 defect and has no effect on the -1/2 that remains a non-motile particle. A sharp jump in activity acts like a wall that traps the defects, affecting the translational and rotational motion of both charges. The +1/2 defect slows down as it approaches the interface and the net vorticity tends to reorient the defect polarization so that it becomes perpendicular to the interface. The -1/2 defect acquires a self-propulsion towards the activity interface, while the vorticity-induced active torque tends to align the defect to a preferred orientation. This effective attraction of the negative defects to the wall is consistent with the observation of an accumulation of negative topological charge at both active/passive interfaces and physical boundaries.
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Affiliation(s)
- Jonas Rønning
- Njord Centre, Department of Physics, University of Oslo, PO Box 1048, Oslo 0316, Norway
| | - M. Cristina Marchetti
- Department of Physics and Biomolecular Science and Engineering Program, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Luiza Angheluta
- Njord Centre, Department of Physics, University of Oslo, PO Box 1048, Oslo 0316, Norway
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27
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Ascione F, Caserta S, Esposito S, Villella VR, Maiuri L, Nejad MR, Doostmohammadi A, Yeomans JM, Guido S. Collective rotational motion of freely expanding T84 epithelial cell colonies. J R Soc Interface 2023; 20:20220719. [PMID: 36872917 PMCID: PMC9943890 DOI: 10.1098/rsif.2022.0719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 01/23/2023] [Indexed: 02/25/2023] Open
Abstract
Coordinated rotational motion is an intriguing, yet still elusive mode of collective cell migration, which is relevant in pathological and morphogenetic processes. Most of the studies on this topic have been carried out on epithelial cells plated on micropatterned substrates, where cell motion is confined in regions of well-defined shapes coated with extracellular matrix adhesive proteins. The driver of collective rotation in such conditions has not been clearly elucidated, although it has been speculated that spatial confinement can play an essential role in triggering cell rotation. Here, we study the growth of epithelial cell colonies freely expanding (i.e. with no physical constraints) on the surface of cell culture plates and focus on collective cell rotation in such conditions, a case which has received scarce attention in the literature. One of the main findings of our work is that coordinated cell rotation spontaneously occurs in cell clusters in the free growth regime, thus implying that cell confinement is not necessary to elicit collective rotation as previously suggested. The extent of collective rotation was size and shape dependent: a highly coordinated disc-like rotation was found in small cell clusters with a round shape, while collective rotation was suppressed in large irregular cell clusters generated by merging of different clusters in the course of their growth. The angular motion was persistent in the same direction, although clockwise and anticlockwise rotations were equally likely to occur among different cell clusters. Radial cell velocity was quite low as compared to the angular velocity, in agreement with the free expansion regime where cluster growth is essentially governed by cell proliferation. A clear difference in morphology was observed between cells at the periphery and the ones in the core of the clusters, the former being more elongated and spread out as compared to the latter. Overall, our results, to our knowledge, provide the first quantitative and systematic evidence that coordinated cell rotation does not require a spatial confinement and occurs spontaneously in freely expanding epithelial cell colonies, possibly as a mechanism for the system.
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Affiliation(s)
- Flora Ascione
- Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale (DICMAPI), Università di Napoli Federico II, P.le Tecchio 80, 80125 Napoli, Italy
| | - Sergio Caserta
- Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale (DICMAPI), Università di Napoli Federico II, P.le Tecchio 80, 80125 Napoli, Italy
- CEINGE Biotecnologie Avanzate, Via Sergio Pansini 5, 80131 Naples, Italy
| | - Speranza Esposito
- Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale (DICMAPI), Università di Napoli Federico II, P.le Tecchio 80, 80125 Napoli, Italy
- European Institute for Research in Cystic Fibrosis, San Raffaele Scientific Institute, Milan, Italy
| | - Valeria Rachela Villella
- Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale (DICMAPI), Università di Napoli Federico II, P.le Tecchio 80, 80125 Napoli, Italy
- European Institute for Research in Cystic Fibrosis, San Raffaele Scientific Institute, Milan, Italy
| | - Luigi Maiuri
- European Institute for Research in Cystic Fibrosis, San Raffaele Scientific Institute, Milan, Italy
| | - Mehrana R. Nejad
- The Rudolf Peierls Centre for Theoretical Physics, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK
| | | | - Julia M. Yeomans
- The Rudolf Peierls Centre for Theoretical Physics, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK
| | - Stefano Guido
- Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale (DICMAPI), Università di Napoli Federico II, P.le Tecchio 80, 80125 Napoli, Italy
- CEINGE Biotecnologie Avanzate, Via Sergio Pansini 5, 80131 Naples, Italy
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28
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Ai BQ, Ma J, Zeng CH, He YF. Emergence of macroscopic directional motion of deformable active cells in confined structures. Phys Rev E 2023; 107:024406. [PMID: 36932507 DOI: 10.1103/physreve.107.024406] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
There is now growing evidence of collective turbulentlike motion of cells in dense tissues. However, how to control and harness this collective motion is an open question. We investigate the transport of deformable active cells in a periodically asymmetric channel by using a phase-field model. We demonstrate that collective turbulent-like motion of cells can power and steer the macroscopic directional motion through the ratchet channel. The active intercellular forces proportional to the deformation of cells can break thermodynamical equilibrium and induce the directional motion. This directional motion is caused by the ratchet effect rather than the spontaneous symmetry breaking. The motion direction is determined by the asymmetry of the channel. Remarkably, there exits an optimal nonequilibrium driving (depending on the active strength, the elasticity, and the packing fraction) at which the average velocity reaches the maximum. In addition, the optimized packing fraction and the optimized minimum width of the channel can facilitate the directional motion of cells. Our findings are relevant to understanding how macroscopic directional motion relates to the local force transmission mediated by cell-cell contacts in cellular monolayers.
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Affiliation(s)
- Bao-Quan Ai
- Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006, China
- Guangdong-Hong Kong Joint Laboratory of Quantum Matter, South China Normal University, Guangzhou 510006, China
| | - Jian Ma
- Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006, China
| | - Chun-Hua Zeng
- Faculty of Science, Kunming University of Science and Technology, Kunming 650500, China
| | - Ya-Feng He
- College of Physics Science and Technology, Hebei University, Baoding 071002, China
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29
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Zhang G, Yeomans JM. Active Forces in Confluent Cell Monolayers. PHYSICAL REVIEW LETTERS 2023; 130:038202. [PMID: 36763395 DOI: 10.1103/physrevlett.130.038202] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 12/22/2022] [Indexed: 06/18/2023]
Abstract
We use a computational phase-field model together with analytical analysis to study how intercellular active forces can mediate individual cell morphology and collective motion in a confluent cell monolayer. We explore the regime where intercellular forces dominate the tissue dynamics, and polar forces are negligible. Contractile intercellular interactions lead to cell elongation, nematic ordering, and active turbulence characterized by motile topological defects. Extensile interactions result in frustration, and perpendicular cell orientations become more prevalent. Furthermore, we show that contractile behavior can change to extensile behavior if anisotropic fluctuations in cell shape are considered.
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Affiliation(s)
- Guanming Zhang
- Department of Physics, The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Julia M Yeomans
- Department of Physics, The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
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30
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Khoromskaia D, Salbreux G. Active morphogenesis of patterned epithelial shells. eLife 2023; 12:75878. [PMID: 36649186 PMCID: PMC9844985 DOI: 10.7554/elife.75878] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2021] [Accepted: 11/18/2022] [Indexed: 01/11/2023] Open
Abstract
Shape transformations of epithelial tissues in three dimensions, which are crucial for embryonic development or in vitro organoid growth, can result from active forces generated within the cytoskeleton of the epithelial cells. How the interplay of local differential tensions with tissue geometry and with external forces results in tissue-scale morphogenesis remains an open question. Here, we describe epithelial sheets as active viscoelastic surfaces and study their deformation under patterned internal tensions and bending moments. In addition to isotropic effects, we take into account nematic alignment in the plane of the tissue, which gives rise to shape-dependent, anisotropic active tensions and bending moments. We present phase diagrams of the mechanical equilibrium shapes of pre-patterned closed shells and explore their dynamical deformations. Our results show that a combination of nematic alignment and gradients in internal tensions and bending moments is sufficient to reproduce basic building blocks of epithelial morphogenesis, including fold formation, budding, neck formation, flattening, and tubulation.
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Affiliation(s)
| | - Guillaume Salbreux
- The Francis Crick InstituteLondonUnited Kingdom
- University of GenevaGenevaSwitzerland
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31
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Cockerell A, Wright L, Dattani A, Guo G, Smith A, Tsaneva-Atanasova K, Richards DM. Biophysical models of early mammalian embryogenesis. Stem Cell Reports 2023; 18:26-46. [PMID: 36630902 PMCID: PMC9860129 DOI: 10.1016/j.stemcr.2022.11.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 11/02/2022] [Accepted: 11/24/2022] [Indexed: 01/12/2023] Open
Abstract
Embryo development is a critical and fascinating stage in the life cycle of many organisms. Despite decades of research, the earliest stages of mammalian embryogenesis are still poorly understood, caused by a scarcity of high-resolution spatial and temporal data, the use of only a few model organisms, and a paucity of truly multidisciplinary approaches that combine biological research with biophysical modeling and computational simulation. Here, we explain the theoretical frameworks and biophysical processes that are best suited to modeling the early mammalian embryo, review a comprehensive list of previous models, and discuss the most promising avenues for future work.
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Affiliation(s)
- Alaina Cockerell
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Liam Wright
- Department of Mathematics, University of Exeter, North Park Road, Exeter EX4 4QF, UK
| | - Anish Dattani
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Ge Guo
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Austin Smith
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK
| | - Krasimira Tsaneva-Atanasova
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK; Department of Mathematics, University of Exeter, North Park Road, Exeter EX4 4QF, UK; EPSRC Hub for Quantitative Modelling in Healthcare, University of Exeter, Exeter EX4 4QJ, UK; Department of Bioinformatics and Mathematical Modelling, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, 105 Acad. G. Bonchev Street, 1113 Sofia, Bulgaria
| | - David M Richards
- Living Systems Institute, University of Exeter, Stocker Road, Exeter EX4 4QD, UK; Department of Physics and Astronomy, University of Exeter, North Park Road, Exeter EX4 4QL, UK.
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32
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Sonam S, Balasubramaniam L, Lin SZ, Ivan YMY, Jaumà IP, Jebane C, Karnat M, Toyama Y, Marcq P, Prost J, Mège RM, Rupprecht JF, Ladoux B. Mechanical stress driven by rigidity sensing governs epithelial stability. NATURE PHYSICS 2023; 19:132-141. [PMID: 36686215 PMCID: PMC7614076 DOI: 10.1038/s41567-022-01826-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Epithelia act as a barrier against environmental stress and abrasion and in vivo they are continuously exposed to environments of various mechanical properties. The impact of this environment on epithelial integrity remains elusive. By culturing epithelial cells on 2D hydrogels, we observe a loss of epithelial monolayer integrity through spontaneous hole formation when grown on soft substrates. Substrate stiffness triggers an unanticipated mechanical switch of epithelial monolayers from tensile on soft to compressive on stiff substrates. Through active nematic modelling, we find that spontaneous half-integer defect formation underpinning large isotropic stress fluctuations initiate hole opening events. Our data show that monolayer rupture due to high tensile stress is promoted by the weakening of cell-cell junctions that could be induced by cell division events or local cellular stretching. Our results show that substrate stiffness provides feedback on monolayer mechanical state and that topological defects can trigger stochastic mechanical failure, with potential application towards a mechanistic understanding of compromised epithelial integrity during immune response and morphogenesis.
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Affiliation(s)
- Surabhi Sonam
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
| | | | - Shao-Zhen Lin
- Aix Marseille Univ, Université de Toulon, CNRS, CPT, Turing Center for Living Systems, Marseille, France
| | | | - Irina Pi Jaumà
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
| | - Cecile Jebane
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
| | - Marc Karnat
- Aix Marseille Univ, Université de Toulon, CNRS, CPT, Turing Center for Living Systems, Marseille, France
| | - Yusuke Toyama
- Mechanobiology Institute, National University of Singapore, Singapore
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Philippe Marcq
- Physique et Mécanique des Milieux Hétérogènes, CNRS, ESPCI Paris, PSL University, Sorbonne Université, Université de Paris, 75005, Paris, France
| | - Jacques Prost
- Mechanobiology Institute, National University of Singapore, Singapore
- Physico-Chimie Curie, Institut Curie, CNRS UMR 168, Paris, France
| | - René-Marc Mège
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
| | - Jean-François Rupprecht
- Aix Marseille Univ, Université de Toulon, CNRS, CPT, Turing Center for Living Systems, Marseille, France
- Corresponding authors Dr. Benoit Ladoux, , Dr. Jean-François Rupprecht,
| | - Benoît Ladoux
- Université de Paris, CNRS, Institut Jacques Monod, F-75006 Paris, France
- Corresponding authors Dr. Benoit Ladoux, , Dr. Jean-François Rupprecht,
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33
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Katuri J, Snezhko A, Sokolov A. Motility of acoustically powered micro-swimmers in a liquid crystalline environment. SOFT MATTER 2022; 18:8641-8646. [PMID: 36342339 DOI: 10.1039/d2sm01171a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Suspensions of microswimmers in liquid crystals demonstrate remarkably complex dynamics and serve as a model system for studying active nematics. So far, experimental realization of microswimmers suspended in liquid crystalline media has relied on biological microorganisms that impose strict limitations on the compatible media and makes it difficult to regulate activity. Here, we demonstrate that acoustically powered bubble microswimmers can efficiently self-propel in a lyotropic liquid crystal. The velocity of the swimmers is controlled by the amplitude of the acoustic field. Histograms of swimming directions with respect to the local nematic field reveal a bimodal distribution: the swimmers tend to either fully align with or swim perpendicular to the director field of the liquid crystal, occasionally switching between these two states. The bubble-induced streaming from a swimmer locally melts the liquid crystal and produces topological defects at the tail of the swimmer. We show that the defect proliferation rate increases with the angle between the swimmer's velocity and the local orientation of the director field.
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Affiliation(s)
- Jaideep Katuri
- Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL, 60439, USA.
| | - Alexey Snezhko
- Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL, 60439, USA.
| | - Andrey Sokolov
- Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL, 60439, USA.
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34
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Zhang YX, Liu CY, Chen HY, I L. Spontaneous multi-scale void formation and closure in densifying epithelial and fibroblast monolayers from the sub-confluent state. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2022; 45:89. [PMID: 36346482 DOI: 10.1140/epje/s10189-022-00242-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 10/23/2022] [Indexed: 06/16/2023]
Abstract
Using time-lapse phase contrast microscopy, the formation and closure of spontaneously generated voids in the densifying monolayers of isotropic epithelial cells (ECs) and elongated fibroblast cells (FCs) through proliferation from the sub-confluent state are investigated. It is found that, in both types of monolayers after forming a connected network composed of nematic patches with different orientations, numerous multi-scale voids can be spontaneously formed and gradually close with increasing time. The isotropic fluctuations of deformation and crawling of ECs and the anisotropic axial motion/alignment polarizations of FCs are the two keys leading to the following different generic dynamical behaviors. In EC monolayers, voids exhibit irregular boundary fluctuations and easier cell re-orientation of front layer cells (FLCs) surrounding void boundaries. Void closures are mainly through pinching the gap between the opposite fluctuating void boundaries, and the inward crawling of FLCs to reduce void area associated with topological rearrangement to reduce FLC number. In FC monolayers, large voids have piecewise smooth convex boundaries, and cusp-shaped concave boundaries with cells orienting toward the void at cusp tips. The extension of a thin cell bridge from the cusp tip can bisect a large void into smaller voids. For smaller FC voids dominated by convex boundaries, along which cell alignment prohibits inward crawling, the reduction of FLC number through successive outward squeezing of single FLCs by neighboring FLCs sliding along the void boundary plays an important role for topological rearrangement and void closure. Unlike those surrounding artificial wounds in dense EC monolayers, the absence of ring-like purse-strings surrounding EC and FC voids allows topological rearrangements for reducing void perimeter and void area.
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Affiliation(s)
- Yun-Xuan Zhang
- Department of Physics and Center for Complex Systems, National Central University, Jhongli, 32001, Taiwan
| | - Chun-Yu Liu
- Department of Physics and Center for Complex Systems, National Central University, Jhongli, 32001, Taiwan
| | - Hsiang-Ying Chen
- Department of Physics and Center for Complex Systems, National Central University, Jhongli, 32001, Taiwan
| | - Lin I
- Department of Physics and Center for Complex Systems, National Central University, Jhongli, 32001, Taiwan.
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35
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Fuji K, Tanida S, Sano M, Nonomura M, Riveline D, Honda H, Hiraiwa T. Computational approaches for simulating luminogenesis. Semin Cell Dev Biol 2022; 131:173-185. [PMID: 35773151 DOI: 10.1016/j.semcdb.2022.05.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 05/24/2022] [Accepted: 05/24/2022] [Indexed: 12/14/2022]
Abstract
Lumens, liquid-filled cavities surrounded by polarized tissue cells, are elementary units involved in the morphogenesis of organs. Theoretical modeling and computations, which can integrate various factors involved in biophysics of morphogenesis of cell assembly and lumens, may play significant roles to elucidate the mechanisms in formation of such complex tissue with lumens. However, up to present, it has not been documented well what computational approaches or frameworks can be applied for this purpose and how we can choose the appropriate approach for each problem. In this review, we report some typical lumen morphologies and basic mechanisms for the development of lumens, focusing on three keywords - mechanics, hydraulics and geometry - while outlining pros and cons of the current main computational strategies. We also describe brief guidance of readouts, i.e., what we should measure in experiments to make the comparison with the model's assumptions and predictions.
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Affiliation(s)
- Kana Fuji
- Universal Biology Institute, Graduate School of Science, the University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Sakurako Tanida
- Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, Japan
| | - Masaki Sano
- Institute of Natural Sciences, School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Makiko Nonomura
- Department of Mathematical Information Engineering, College of Industrial Technology, Nihon University, 1-2-1 Izumicho, Narashino-shi, Chiba 275-8575, Japan
| | - Daniel Riveline
- Laboratory of Cell Physics IGBMC, CNRS, INSERM and Université de Strasbourg, Strasbourg, France
| | - Hisao Honda
- Division of Cell Physiology, Department of Physiology and Cell Biology, Graduate School of Medicine Kobe University, Kobe, Hyogo, Japan
| | - Tetsuya Hiraiwa
- Mechanobiology Institute, Singapore, National University of Singapore, 117411, Singapore.
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36
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Zadeh P, Camley BA. Picking winners in cell-cell collisions: Wetting, speed, and contact. Phys Rev E 2022; 106:054413. [PMID: 36559372 DOI: 10.1103/physreve.106.054413] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 09/27/2022] [Indexed: 06/17/2023]
Abstract
Groups of eukaryotic cells can coordinate their crawling motion to follow cues more effectively, stay together, or invade new areas. This collective cell migration depends on cell-cell interactions, which are often studied by colliding pairs of cells together. Can the outcome of these collisions be predicted? Recent experiments on trains of colliding epithelial cells suggest that cells with a smaller contact angle to the surface or larger speeds are more likely to maintain their direction ("win") upon collision. When should we expect shape or speed to correlate with the outcome of a collision? To investigate this question, we build a model for two-cell collisions within the phase field framework, which allows for cell shape changes. We can reproduce the observation that cells with high speed and small contact angles are more likely to win with two different assumptions for how cells interact: (1) velocity aligning, in which we hypothesize that cells sense their own velocity and align to it over a finite timescale, and (2) front-front contact repolarization, where cells polarize away from cell-cell contact, akin to contact inhibition of locomotion. Surprisingly, though we simulate collisions between cells with widely varying properties, in each case, the probability of a cell winning is completely captured by a single summary variable: its relative speed (in the velocity-aligning model) or its relative contact angle (in the contact repolarization model). Both models are currently consistent with reported experimental results, but they can be distinguished by varying cell contact angle and speed through orthogonal perturbations.
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Affiliation(s)
- Pedrom Zadeh
- William H. Miller III Department of Physics & Astronomy, Johns Hopkins University, Baltimore, Maryland 21210, USA
| | - Brian A Camley
- William H. Miller III Department of Physics & Astronomy, Johns Hopkins University, Baltimore, Maryland 21210, USA
- Department of Biophysics, Johns Hopkins University, Baltimore, Maryland 21218, USA
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37
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Hopkins A, Chiang M, Loewe B, Marenduzzo D, Marchetti MC. Local Yield and Compliance in Active Cell Monolayers. PHYSICAL REVIEW LETTERS 2022; 129:148101. [PMID: 36240394 DOI: 10.1103/physrevlett.129.148101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Accepted: 08/23/2022] [Indexed: 06/16/2023]
Abstract
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 of motile cells to simulate active microrheology within a tissue monolayer. When unperturbed, the tissue exhibits a transition between a solidlike state and a fluidlike state tuned by cell motility and deformability-the ratio of the energetic costs of steric cell-cell repulsion and cell-edge tension. When perturbed, solid tissues exhibit local yield-stress behavior, with a threshold force for the onset of motion of a probe particle that vanishes upon approaching the solid-to-liquid transition. This onset of motion is qualitatively different in the low and high deformability regimes. At high deformability, the tissue is amorphous when solid, it responds compliantly to deformations, and the probe transition to motion is smooth. At low deformability, the monolayer is more ordered translationally and stiffer, and the onset of motion appears discontinuous. Our results suggest that cellular or nanoparticle transport in different types of tissues can be fundamentally different and point to ways in which it can be controlled.
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Affiliation(s)
- Austin Hopkins
- Department of Physics, University of California Santa Barbara, Santa Barbara, California 93106, USA
| | - Michael Chiang
- SUPA, School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, United Kingdom
| | - Benjamin Loewe
- SUPA, School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, United Kingdom
| | - Davide Marenduzzo
- SUPA, School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, United Kingdom
| | - M Cristina Marchetti
- Department of Physics, University of California Santa Barbara, Santa Barbara, California 93106, USA
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38
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Ruske LJ, Yeomans JM. Activity gradients in two- and three-dimensional active nematics. SOFT MATTER 2022; 18:5654-5661. [PMID: 35861255 DOI: 10.1039/d2sm00228k] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
We numerically investigate how spatial variations of extensile or contractile active stress affect bulk active nematic systems in two and three dimensions. In the absence of defects, activity gradients drive flows which re-orient the nematic director field and thus act as an effective anchoring force. At high activity, defects are created and the system transitions into active turbulence, a chaotic flow state characterized by strong vorticity. We find that in two-dimensional (2D) systems active torques robustly align +1/2 defects parallel to activity gradients, with defect heads pointing towards contractile regions. In three-dimensional (3D) active nematics disclination lines preferentially lie in the plane perpendicular to activity gradients due to active torques acting on line segments. The average orientation of the defect structures in the plane perpendicular to the line tangent depends on the defect type, where wedge-like +1/2 defects align parallel to activity gradients, while twist defects are aligned anti-parallel. Understanding the response of active nematic fluids to activity gradients is an important step towards applying physical theories to biology, where spatial variations of active stress impact morphogenetic processes in developing embryos and affect flows and deformations in growing cell aggregates, such as tumours.
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Affiliation(s)
- Liam J Ruske
- Rudolf Peierls Centre for Theoretical Physics, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK.
| | - Julia M Yeomans
- Rudolf Peierls Centre for Theoretical Physics, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK.
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39
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Ardaševa A, Mueller R, Doostmohammadi A. Bridging microscopic cell dynamics to nematohydrodynamics of cell monolayers. SOFT MATTER 2022; 18:4737-4746. [PMID: 35703313 DOI: 10.1039/d2sm00537a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
It is increasingly being realized that liquid-crystalline features can play an important role in the properties and dynamics of cell monolayers. Here, we present a cell-based model of cell layers, based on the phase-field formulation, that connects cell-cell interactions specified at the single cell level to large-scale nematic and hydrodynamic properties of the tissue. In particular, we present a minimal formulation that reproduces the well-known bend and splay hydrodynamic instabilities of the continuum nemato-hydrodynamic formulation of active matter, together with an analytical description of the instability threshold in terms of activity and elasticity of the cells. Furthermore, we provide a quantitative characterisation and comparison of flows and topological defects for extensile and contractile stress generation mechanisms, and demonstrate activity-induced heterogeneity and spontaneous formation of gaps within a confluent monolayer. Together, these results contribute to bridging the gap between cell-scale dynamics and tissue-scale collective cellular organisation.
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Affiliation(s)
| | - Romain Mueller
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, UK
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40
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Sultan SA, R Nejad M, Doostmohammadi A. Quadrupolar active stress induces exotic patterns of defect motion in compressible active nematics. SOFT MATTER 2022; 18:4118-4126. [PMID: 35579323 DOI: 10.1039/d1sm01683k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
A wide range of living and artificial active matter exists in close contact with substrates and under strong confinement, where in addition to dipolar active stresses, quadrupolar active stresses can become important. Here, we numerically investigate the impact of quadrupolar non-equilibrium stresses on the emergent patterns of self-organisation in non-momentum conserving active nematics. Our results reveal that beyond having stabilising effects, the quadrupolar active forces can induce various modes of topological defect motion in active nematics. In particular, we find the emergence of both polar and nematic ordering of the defects, as well as new patterns of self-organisation that comprise topological defect chains and transient topological defect asters. The results contribute to further understanding of emergent patterns of collective motion and non-equilibrium self-organisation in active matter.
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Affiliation(s)
- Salik A Sultan
- The Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
| | - Mehrana R Nejad
- Rudolf Peierls Centre for Theoretical Physics, University of Oxford, UK
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41
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Jain HP, Wenzel D, Voigt A. Impact of contact inhibition on collective cell migration and proliferation. Phys Rev E 2022; 105:034402. [PMID: 35428163 DOI: 10.1103/physreve.105.034402] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 02/09/2022] [Indexed: 06/14/2023]
Abstract
Contact inhibition limits migration and proliferation of cells in cell colonies. We consider a multiphase field model to investigate the growth dynamics of a cell colony, composed of proliferating cells. The model takes into account the mechanism of contact inhibition of proliferation by local mechanical interactions. We compare nonmigrating and migrating cells, in order to provide a quantitative characterization of the dynamics and analyze the velocity of the colony boundary for both cases. Additionally, we measure single cell velocities, number of neighbor distributions, as well as the influence of stress and age on positions of the cells and with respect to each other.
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Affiliation(s)
- H P Jain
- Institute of Scientific Computing, Technische Universität Dresden, D-01062 Dresden, Germany
| | - D Wenzel
- Institute of Scientific Computing, Technische Universität Dresden, D-01062 Dresden, Germany
| | - A Voigt
- Institute of Scientific Computing, Technische Universität Dresden, D-01062 Dresden, Germany
- Center for Systems Biology Dresden (CSBD), Pfotenhauerstr. 108, D-01307 Dresden, Germany
- Cluster of Excellence - Physics of Life, TU Dresden, D-01062 Dresden, Germany
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42
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Killeen A, Bertrand T, Lee CF. Polar Fluctuations Lead to Extensile Nematic Behavior in Confluent Tissues. PHYSICAL REVIEW LETTERS 2022; 128:078001. [PMID: 35244433 DOI: 10.1103/physrevlett.128.078001] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 11/10/2021] [Accepted: 01/06/2022] [Indexed: 06/14/2023]
Abstract
How can a collection of motile cells, each generating contractile nematic stresses in isolation, become an extensile nematic at the tissue level? Understanding this seemingly contradictory experimental observation, which occurs irrespective of whether the tissue is in the liquid or solid states, is not only crucial to our understanding of diverse biological processes, but is also of fundamental interest to soft matter and many-body physics. Here, we resolve this cellular to tissue level disconnect in the small fluctuation regime by using analytical theories based on hydrodynamic descriptions of confluent tissues, in both liquid and solid states. Specifically, we show that a collection of microscopic constituents with no inherently nematic extensile forces can exhibit active extensile nematic behavior when subject to polar fluctuating forces. We further support our findings by performing cell level simulations of minimal models of confluent tissues.
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Affiliation(s)
- Andrew Killeen
- Department of Bioengineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Thibault Bertrand
- Department of Mathematics, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Chiu Fan Lee
- Department of Bioengineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
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43
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Krause V, Voigt A. Deformable active nematic particles and emerging edge currents in circular confinements. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2022; 45:14. [PMID: 35175445 PMCID: PMC8854302 DOI: 10.1140/epje/s10189-022-00162-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Accepted: 01/08/2022] [Indexed: 06/14/2023]
Abstract
We consider a microscopic field theoretical approach for interacting active nematic particles. With only steric interactions the self-propulsion strength in such systems can lead to different collective behaviour, e.g. synchronized self-spinning and collective translation. The different behaviour results from the delicate interplay between internal nematic structure, particle shape deformation and particle-particle interaction. For intermediate active strength an asymmetric particle shape emerges and leads to chirality and self-spinning crystals. For larger active strength the shape is symmetric and translational collective motion emerges. Within circular confinements, depending on the packing fraction, the self-spinning regime either stabilizes positional and orientational order or can lead to edge currents and global rotation which destroys the synchronized self-spinning crystalline structure.
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Affiliation(s)
- Veit Krause
- Institut für Wissenschaftliches Rechnen, TU Dresden, 01062, Dresden, Germany
| | - Axel Voigt
- Institut für Wissenschaftliches Rechnen, TU Dresden, 01062, Dresden, Germany.
- Center for Systems Biology Dresden (CSBD), Pfotenhauerstr. 108, 01307, Dresden, Germany.
- Cluster of Excellence, Physics of Life, TU Dresden, 01062, Dresden, Germany.
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44
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Rønning J, Marchetti CM, Bowick MJ, Angheluta L. Flow around topological defects in active nematic films. Proc Math Phys Eng Sci 2022; 478:20210879. [PMID: 35153617 PMCID: PMC8791053 DOI: 10.1098/rspa.2021.0879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 12/22/2021] [Indexed: 11/14/2022] Open
Abstract
We study the active flow around isolated defects and the self-propulsion velocity of +1/2 defects in an active nematic film with both viscous dissipation (with viscosity η) and frictional damping Γ with a substrate. The interplay between these two dissipation mechanisms is controlled by the hydrodynamic dissipation length ℓd=η/Γ that screens the flows. For an isolated defect, in the absence of screening from other defects, the size of the shear vorticity around the defect is controlled by the system size R. In the presence of friction that leads to a finite value of ℓd, the vorticity field decays to zero on the lengthscales larger than ℓd. We show that the self-propulsion velocity of +1/2 defects grows with R in small systems where R<ℓd, while in the infinite system limit or when R≫ℓd, it approaches a constant value determined by ℓd.
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Affiliation(s)
- Jonas Rønning
- Njord Centre, Department of Physics, University of Oslo, PO Box 1048, Oslo 0316, Norway
| | - Cristina M Marchetti
- Department of Physics, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Mark J Bowick
- Kavli Institute for Theoretical Physics, University of California Santa Barbara, Santa Barbara, CA 93106, USA
| | - Luiza Angheluta
- Njord Centre, Department of Physics, University of Oslo, PO Box 1048, Oslo 0316, Norway
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45
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Wenzel D, Voigt A. Multiphase field models for collective cell migration. Phys Rev E 2021; 104:054410. [PMID: 34942697 DOI: 10.1103/physreve.104.054410] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 11/05/2021] [Indexed: 01/23/2023]
Abstract
Confluent cell monolayers and epithelia tissues show remarkable patterns and correlations in structural arrangements and actively driven collective flows. We simulate these properties using multiphase field models. The models are based on cell deformations and cell-cell interactions and we investigate the influence of microscopic details to incorporate active forces on emerging phenomena. We compare four different approaches, one in which the activity is determined by a random orientation, one where the activity is related to the deformation of the cells, and two models with subcellular details to resolve the mechanochemical interactions underlying cell migration. The models are compared with respect to generic features, such as coordination number distribution, cell shape variability, emerging nematic properties, as well as vorticity correlations and flow patterns in large confluent monolayers and confinements. All results are compared with experimental data for a large variety of cell cultures. The appearing qualitative differences of the models show the importance of microscopic details and provide a route towards predictive simulations of patterns and correlations in cell colonies.
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Affiliation(s)
- D Wenzel
- Institute of Scientific Computing, Technische Universität Dresden, 01062 Dresden, Germany
| | - A Voigt
- Institute of Scientific Computing, Technische Universität Dresden, 01062 Dresden, Germany.,Center for Systems Biology Dresden (CSBD), Pfotenhauerstr. 108, 01307 Dresden, Germany.,Cluster of Excellence-Physics of Life, TU Dresden, 01062 Dresden, Germany
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46
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Aslyamov T, Akhatov I. Extension of van der Waals theory for supersaturated thin films. Phys Chem Chem Phys 2021; 23:25776-25783. [PMID: 34755731 DOI: 10.1039/d1cp03619j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The vapor/liquid interface properties play an essential role in both fundamental models and practical applications. Here, we describe a thin planar film surrounded by supersaturated vapor using the extension of van der Waals theory. We derive the analytical equilibrium conditions, which allow us to define the stress tensor and surface tension. Our model provides the surface tension dependence on the film thickness, correctly reflecting the vapor/liquid interface until full disappearance. The numerical estimations show that the surface tension crucially depends on the film thickness-a decrease in the thickness of 50% results in an 85% reduction in the surface tension.
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Affiliation(s)
- Timur Aslyamov
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow, 121205, Russia.
| | - Iskander Akhatov
- Skolkovo Institute of Science and Technology, Bolshoy Boulevard 30, bld. 1, Moscow, 121205, Russia.
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47
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Paoluzzi M, Angelani L, Gosti G, Marchetti MC, Pagonabarraga I, Ruocco G. Alignment interactions drive structural transitions in biological tissues. Phys Rev E 2021; 104:044606. [PMID: 34781522 DOI: 10.1103/physreve.104.044606] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/23/2021] [Indexed: 12/24/2022]
Abstract
Experimental evidence shows that there is a feedback between cell shape and cell motion. How this feedback impacts the collective behavior of dense cell monolayers remains an open question. We investigate the effect of a feedback that tends to align the cell crawling direction with cell elongation in a biological tissue model. We find that the alignment interaction promotes nematic patterns in the fluid phase that eventually undergo a nonequilibrium phase transition into a quasihexagonal solid. Meanwhile, highly asymmetric cells do not undergo the liquid-to-solid transition for any value of the alignment coupling. In this regime, the dynamics of cell centers and shape fluctuation show features typical of glassy systems.
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Affiliation(s)
- Matteo Paoluzzi
- Departament de Física de la Matèria Condensada, Universitat de Barcelona, C. Martí Franquès 1, 08028 Barcelona, Spain
| | - Luca Angelani
- ISC-CNR, Institute for Complex Systems, Piazzale A. Moro 2, I-00185 Rome, Italy.,Dipartimento di Fisica, Sapienza Università di Roma Piazzale A. Moro 2, I-00185 Rome, Italy
| | - Giorgio Gosti
- Center for Life Nano Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, I-00161 Rome, Italy
| | - M Cristina Marchetti
- Department of Physics, University of California Santa Barbara, Santa Barbara, California 93106, USA
| | - Ignacio Pagonabarraga
- Departament de Física de la Matèria Condensada, Universitat de Barcelona, C. Martí Franquès 1, 08028 Barcelona, Spain.,CECAM Centre Européen de Calcul Atomique et Moléculaire, École Polytechnique Fédérale de Lausanne (EPFL), Batochime, Avenue Forel 2, 1015 Lausanne, Switzerland.,UBICS University of Barcelona Institute of Complex Systems, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Giancarlo Ruocco
- Dipartimento di Fisica, Sapienza Università di Roma Piazzale A. Moro 2, I-00185 Rome, Italy.,Center for Life Nano Science, Istituto Italiano di Tecnologia, Viale Regina Elena 291, I-00161 Rome, Italy
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48
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Physics of liquid crystals in cell biology. Trends Cell Biol 2021; 32:140-150. [PMID: 34756501 DOI: 10.1016/j.tcb.2021.09.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 09/28/2021] [Accepted: 09/30/2021] [Indexed: 11/21/2022]
Abstract
The past decade has witnessed a rapid growth in understanding of the pivotal roles of mechanical stresses and physical forces in cell biology. As a result, an integrated view of cell biology is evolving, where genetic and molecular features are scrutinised hand in hand with physical and mechanical characteristics of cells. Physics of liquid crystals has emerged as a burgeoning new frontier in cell biology over the past few years, fuelled by an increasing identification of orientational order and topological defects in cell biology, spanning scales from subcellular filaments to individual cells and multicellular tissues. Here, we provide an account of the most recent findings and developments, together with future promises and challenges in this rapidly evolving interdisciplinary research direction.
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49
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Sampat PB, Mishra S. Polar swimmers induce several phases in active nematics. Phys Rev E 2021; 104:024130. [PMID: 34525577 DOI: 10.1103/physreve.104.024130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 07/16/2021] [Indexed: 01/04/2023]
Abstract
Swimming bacteria in passive nematics in the form of lyotropic liquid crystals are defined as a new class of active matter known as living liquid crystals in recent studies. It has also been shown that liquid crystal solutions are promising candidates for trapping and detecting bacteria. We ask the question, can a similar class of matter be designed for background nematics which are also active? Hence, we developed a minimal model for the mixture of polar particles in active nematics. It is found that the active nematics in such a mixture are highly sensitive to the presence of polar particles and show the formation of large scale higher order structures for a relatively low polar particle density. Upon increasing the density of polar particles, different phases of active nematics are found and it is observed that the system shows two phase transitions. The first phase transition is a first order transition from quasi-long-ranged ordered active nematics to disordered active nematics with larger scale structures. On further increasing density of polar particles, the system transitions to a third phase, where polar particles form large, mutually aligned clusters. These clusters sweep the whole system and enforce local order in the nematics. The current study can be helpful for detecting the presence of very low densities of polar swimmers in active nematics and can be used to design and control different structures in active nematics.
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Affiliation(s)
- Pranay Bimal Sampat
- Department of Physics, Indian Institute of Technology (BHU), Varanasi, U.P. - 221005 India
| | - Shradha Mishra
- Department of Physics, Indian Institute of Technology (BHU), Varanasi, U.P. - 221005 India
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50
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Balasubramaniam L, Doostmohammadi A, Saw TB, Narayana GHNS, Mueller R, Dang T, Thomas M, Gupta S, Sonam S, Yap AS, Toyama Y, Mège RM, Yeomans JM, Ladoux B. Investigating the nature of active forces in tissues reveals how contractile cells can form extensile monolayers. NATURE MATERIALS 2021; 20:1156-1166. [PMID: 33603188 PMCID: PMC7611436 DOI: 10.1038/s41563-021-00919-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Accepted: 12/23/2020] [Indexed: 05/24/2023]
Abstract
Actomyosin machinery endows cells with contractility at a single-cell level. However, within a monolayer, cells can be contractile or extensile based on the direction of pushing or pulling forces exerted by their neighbours or on the substrate. It has been shown that a monolayer of fibroblasts behaves as a contractile system while epithelial or neural progentior monolayers behave as an extensile system. Through a combination of cell culture experiments and in silico modelling, we reveal the mechanism behind this switch in extensile to contractile as the weakening of intercellular contacts. This switch promotes the build-up of tension at the cell-substrate interface through an increase in actin stress fibres and traction forces. This is accompanied by mechanotransductive changes in vinculin and YAP activation. We further show that contractile and extensile differences in cell activity sort cells in mixtures, uncovering a generic mechanism for pattern formation during cell competition, and morphogenesis.
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Affiliation(s)
| | - Amin Doostmohammadi
- Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark.
- The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, UK.
| | - Thuan Beng Saw
- Mechanobiology Institute (MBI), National University of Singapore, Singapore, Singapore
- National University of Singapore, Department of Biomedical Engineering, Singapore, Singapore
| | | | - Romain Mueller
- The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, UK
| | - Tien Dang
- Université de Paris, CNRS, Institut Jacques Monod (IJM), Paris, France
| | - Minnah Thomas
- Mechanobiology Institute (MBI), National University of Singapore, Singapore, Singapore
| | - Shafali Gupta
- Division of Cell and Developmental Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Surabhi Sonam
- Université de Paris, CNRS, Institut Jacques Monod (IJM), Paris, France
- D Y Patil International University, Pune, India
| | - Alpha S Yap
- Division of Cell and Developmental Biology, Institute for Molecular Bioscience, The University of Queensland, Brisbane, Australia
| | - Yusuke Toyama
- Mechanobiology Institute (MBI), National University of Singapore, Singapore, Singapore
| | - René-Marc Mège
- Université de Paris, CNRS, Institut Jacques Monod (IJM), Paris, France.
| | - Julia M Yeomans
- The Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford, UK.
| | - Benoît Ladoux
- Université de Paris, CNRS, Institut Jacques Monod (IJM), Paris, France.
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