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Baxendale S, Asad A, Shahidan NO, Wiggin GR, Whitfield TT. The adhesion GPCR Adgrg6 (Gpr126): Insights from the zebrafish model. Genesis 2021; 59:e23417. [PMID: 33735533 DOI: 10.1002/dvg.23417] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 12/13/2022]
Abstract
Adhesion GPCRs are important regulators of conserved developmental processes and represent an untapped pool of potential targets for drug discovery. The adhesion GPCR Adgrg6 (Gpr126) has critical developmental roles in Schwann cell maturation and inner ear morphogenesis in the zebrafish embryo. Mutations in the human ADGRG6 gene can result in severe deficits in peripheral myelination, and variants have been associated with many other disease conditions. Here, we review work on the zebrafish Adgrg6 signaling pathway and its potential as a disease model. Recent advances have been made in the analysis of the structure of the Adgrg6 receptor, demonstrating alternative structural conformations and the presence of a conserved calcium-binding site within the CUB domain of the extracellular region that is critical for receptor function. Homozygous zebrafish adgrg6 hypomorphic mutants have been used successfully as a whole-animal screening platform, identifying candidate molecules that can influence signaling activity and rescue mutant phenotypes. These compounds offer promise for further development as small molecule modulators of Adgrg6 pathway activity.
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Affiliation(s)
- Sarah Baxendale
- Department of Biomedical Science, Bateson Centre and Neuroscience Institute, University of Sheffield, Sheffield, UK
| | - Anzar Asad
- Department of Biomedical Science, Bateson Centre and Neuroscience Institute, University of Sheffield, Sheffield, UK
| | - Nahal O Shahidan
- Department of Biomedical Science, Bateson Centre and Neuroscience Institute, University of Sheffield, Sheffield, UK
| | | | - Tanya T Whitfield
- Department of Biomedical Science, Bateson Centre and Neuroscience Institute, University of Sheffield, Sheffield, UK
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102
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103
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Lv Z, de-Carvalho J, Telley IA, Großhans J. Cytoskeletal mechanics and dynamics in the Drosophila syncytial embryo. J Cell Sci 2021; 134:134/4/jcs246496. [PMID: 33597155 DOI: 10.1242/jcs.246496] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Cell and tissue functions rely on the genetic programmes and cascades of biochemical signals. It has become evident during the past decade that the physical properties of soft material that govern the mechanics of cells and tissues play an important role in cellular function and morphology. The biophysical properties of cells and tissues are determined by the cytoskeleton, consisting of dynamic networks of F-actin and microtubules, molecular motors, crosslinkers and other associated proteins, among other factors such as cell-cell interactions. The Drosophila syncytial embryo represents a simple pseudo-tissue, with its nuclei orderly embedded in a structured cytoskeletal matrix at the embryonic cortex with no physical separation by cellular membranes. Here, we review the stereotypic dynamics and regulation of the cytoskeleton in Drosophila syncytial embryos and how cytoskeletal dynamics underlies biophysical properties and the emergence of collective features. We highlight the specific features and processes of syncytial embryos and discuss the applicability of biophysical approaches.
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Affiliation(s)
- Zhiyi Lv
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao, 266003, China
| | - Jorge de-Carvalho
- Instituto Gulbenkian de Ciência, Fundação Calouste Gulbenkian, 2780-156 Oeiras, Portugal
| | - Ivo A Telley
- Instituto Gulbenkian de Ciência, Fundação Calouste Gulbenkian, 2780-156 Oeiras, Portugal
| | - Jörg Großhans
- Fachbereich Biologie, Philipps-Universität Marburg, 35043 Marburg, Germany
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104
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Du W, Bhojwani A, Hu JK. FACEts of mechanical regulation in the morphogenesis of craniofacial structures. Int J Oral Sci 2021; 13:4. [PMID: 33547271 PMCID: PMC7865003 DOI: 10.1038/s41368-020-00110-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 02/07/2023] Open
Abstract
During embryonic development, organs undergo distinct and programmed morphological changes as they develop into their functional forms. While genetics and biochemical signals are well recognized regulators of morphogenesis, mechanical forces and the physical properties of tissues are now emerging as integral parts of this process as well. These physical factors drive coordinated cell movements and reorganizations, shape and size changes, proliferation and differentiation, as well as gene expression changes, and ultimately sculpt any developing structure by guiding correct cellular architectures and compositions. In this review we focus on several craniofacial structures, including the tooth, the mandible, the palate, and the cranium. We discuss the spatiotemporal regulation of different mechanical cues at both the cellular and tissue scales during craniofacial development and examine how tissue mechanics control various aspects of cell biology and signaling to shape a developing craniofacial organ.
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Affiliation(s)
- Wei Du
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, Sichuan, China
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Arshia Bhojwani
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA
| | - Jimmy K Hu
- School of Dentistry, University of California Los Angeles, Los Angeles, CA, USA.
- Molecular Biology Institute, University of California Los Angeles, Los Angeles, CA, USA.
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105
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Abstract
Epithelial cells possess the ability to change their shape in response to mechanical stress by remodelling their junctions and their cytoskeleton. This property lies at the heart of tissue morphogenesis in embryos. A key feature of embryonic cell shape changes is that they result from repeated mechanical inputs that make them partially irreversible at each step. Past work on cell rheology has rarely addressed how changes can become irreversible in a complex tissue. Here, we review new and exciting findings dissecting some of the physical principles and molecular mechanisms accounting for irreversible cell shape changes. We discuss concepts of mechanical ratchets and tension thresholds required to induce permanent cell deformations akin to mechanical plasticity. Work in different systems has highlighted the importance of actin remodelling and of E-cadherin endocytosis. We also list some novel experimental approaches to fine-tune mechanical tension, using optogenetics, magnetic beads or stretching of suspended epithelial tissues. Finally, we discuss some mathematical models that have been used to describe the quantitative aspects of accounting for mechanical cell plasticity and offer perspectives on this rapidly evolving field.
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Affiliation(s)
- Kelly Molnar
- Sorbonne Université, Institut de Biologie Paris-Seine (IBPS), CNRS UMR7622, 9 Quai St-Bernard, 75005 Paris, France
| | - Michel Labouesse
- Sorbonne Université, Institut de Biologie Paris-Seine (IBPS), CNRS UMR7622, 9 Quai St-Bernard, 75005 Paris, France
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106
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Zhang J, Scarcelli G. Mapping mechanical properties of biological materials via an add-on Brillouin module to confocal microscopes. Nat Protoc 2021; 16:1251-1275. [PMID: 33452504 PMCID: PMC8218248 DOI: 10.1038/s41596-020-00457-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 11/04/2020] [Indexed: 01/29/2023]
Abstract
Several techniques have been developed over the past few decades to assess the mechanical properties of biological samples, which has fueled a rapid growth in the fields of biophysics, bioengineering, and mechanobiology. In this context, Brillouin optical spectroscopy has long been known as an intriguing modality for noncontact material characterization. However, limited by speed and sample damage, it had not translated into a viable imaging modality for biomedically relevant materials. Recently, based on a novel spectroscopy strategy that substantially improves the speed of Brillouin measurement, confocal Brillouin microscopy has emerged as a unique complementary tool to traditional methods as it allows noncontact, nonperturbative, label-free measurements of material mechanical properties. The feasibility and potential of this innovative technique at both the cell and tissue level have been extensively demonstrated over the past decade. As Brillouin technology is rapidly recognized, a standard approach for building and operating Brillouin microscopes is required to facilitate the widespread adoption of this technology. In this protocol, we aim to establish a robust approach for instrumentation, and data acquisition and analysis. By carefully following this protocol, we expect that a Brillouin instrument can be built in 5-9 days by a person with basic optics knowledge and alignment experience; the data acquisition as well as postprocessing can be accomplished within 2-8 h.
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Affiliation(s)
- Jitao Zhang
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA.
| | - Giuliano Scarcelli
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA.
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107
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Shamipour S, Caballero-Mancebo S, Heisenberg CP. Cytoplasm's Got Moves. Dev Cell 2021; 56:213-226. [PMID: 33321104 DOI: 10.1016/j.devcel.2020.12.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 10/22/2020] [Accepted: 11/30/2020] [Indexed: 01/01/2023]
Abstract
Cytoplasm is a gel-like crowded environment composed of various macromolecules, organelles, cytoskeletal networks, and cytosol. The structure of the cytoplasm is highly organized and heterogeneous due to the crowding of its constituents and their effective compartmentalization. In such an environment, the diffusive dynamics of the molecules are restricted, an effect that is further amplified by clustering and anchoring of molecules. Despite the crowded nature of the cytoplasm at the microscopic scale, large-scale reorganization of the cytoplasm is essential for important cellular functions, such as cell division and polarization. How such mesoscale reorganization of the cytoplasm is achieved, especially for large cells such as oocytes or syncytial tissues that can span hundreds of micrometers in size, is only beginning to be understood. In this review, we will discuss recent advances in elucidating the molecular, cellular, and biophysical mechanisms by which the cytoskeleton drives cytoplasmic reorganization across different scales, structures, and species.
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Affiliation(s)
- Shayan Shamipour
- Institute of Science and Technology Austria, Klosterneuburg, Austria
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108
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Özkale B, Sakar MS, Mooney DJ. Active biomaterials for mechanobiology. Biomaterials 2021; 267:120497. [PMID: 33129187 PMCID: PMC7719094 DOI: 10.1016/j.biomaterials.2020.120497] [Citation(s) in RCA: 54] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/23/2020] [Accepted: 10/25/2020] [Indexed: 02/06/2023]
Abstract
Active biomaterials offer novel approaches to study mechanotransduction in mammalian cells. These material systems probe cellular responses by dynamically modulating their resistance to endogenous forces or applying exogenous forces on cells in a temporally controlled manner. Stimuli-responsive molecules, polymers, and nanoparticles embedded inside cytocompatible biopolymer networks transduce external signals such as light, heat, chemicals, and magnetic fields into changes in matrix elasticity (few kPa to tens of kPa) or forces (few pN to several μN) at the cell-material interface. The implementation of active biomaterials in mechanobiology has generated scientific knowledge and therapeutic potential relevant to a variety of conditions including but not limited to cancer metastasis, fibrosis, and tissue regeneration. We discuss the repertoire of cellular responses that can be studied using these platforms including receptor signaling as well as downstream events namely, cytoskeletal organization, nuclear shuttling of mechanosensitive transcriptional regulators, cell migration, and differentiation. We highlight recent advances in active biomaterials and comment on their future impact.
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Affiliation(s)
- Berna Özkale
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA; Wyss Institute for Biologically Inspired Engineering, Cambridge, MA, 02138, USA
| | - Mahmut Selman Sakar
- Institute of Mechanical Engineering and Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015, Lausanne, Switzerland.
| | - David J Mooney
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, 02138, USA; Wyss Institute for Biologically Inspired Engineering, Cambridge, MA, 02138, USA.
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109
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Petet TJ, Deal HE, Zhao HS, He AY, Tang C, Lemmon CA. Rheological characterization of poly-dimethyl siloxane formulations with tunable viscoelastic properties. RSC Adv 2021; 11:35910-35917. [PMID: 35492759 PMCID: PMC9043277 DOI: 10.1039/d1ra03548g] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 10/24/2021] [Indexed: 12/04/2022] Open
Abstract
Studies from the past two decades have demonstrated convincingly that cells are able to sense the mechanical properties of their surroundings. Cells make major decisions in response to this mechanosensation, including decisions regarding cell migration, proliferation, survival, and differentiation. The vast majority of these studies have focused on the cellular mechanoresponse to changing substrate stiffness (or elastic modulus) and have been conducted on purely elastic substrates. In contrast, most soft tissues in the human body exhibit viscoelastic behavior; that is, they generate responsive force proportional to both the magnitude and rate of strain. While several recent studies have demonstrated that viscous effects of an underlying substrate affect cellular mechanoresponse, there is not a straightforward experimental method to probe this, particularly for investigators with little background in biomaterial fabrication. In the current work, we demonstrate that polymers comprised of differing polydimethylsiloxane (PDMS) formulations can be generated that allow for control over both the strain-dependent storage modulus and the strain rate-dependent loss modulus. These substrates requires no background in biomaterial fabrication to fabricate, are shelf-stable, and exhibit repeatable mechanical properties. Here we demonstrate that these substrates are biocompatible and exhibit similar protein adsorption characteristics regardless of mechanical properties. Finally, we develop a set of empirical equations that predicts the storage and loss modulus for a given blend of PDMS formulations, allowing users to tailor substrate mechanical properties to their specific needs. We have generated novel formulations of polydimethyl siloxane with varying viscoelastic properties that can be used to study cellular response. We present equations that can be used to predict the storage and loss moduli of these polymers.![]()
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Affiliation(s)
- Thomas J. Petet
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Halston E. Deal
- Joint Department of Biomedical Engineering, North Carolina State University, University of North Carolina, Chapel Hill, Raleigh, NC, USA
- Comparative Medicine Institute, North Carolina State University, Raleigh, NC, USA
| | - Hanhsen S. Zhao
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Amanda Y. He
- Department of Biology, Duke University, Durham, NC, USA
| | - Christina Tang
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
- Department of Chemical and Life Science Engineering, Virginia Commonwealth University, Richmond, VA, USA
| | - Christopher A. Lemmon
- Department of Biomedical Engineering, Virginia Commonwealth University, Richmond, VA, USA
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110
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Shellard A, Mayor R. Durotaxis: The Hard Path from In Vitro to In Vivo. Dev Cell 2020; 56:227-239. [PMID: 33290722 DOI: 10.1016/j.devcel.2020.11.019] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/21/2020] [Accepted: 11/17/2020] [Indexed: 01/21/2023]
Abstract
Durotaxis, the process by which cells follow gradients of extracellular mechanical stiffness, has been proposed as a mechanism driving directed migration. Despite the lack of evidence for its existence in vivo, durotaxis has become an active field of research, focusing on the mechanism by which cells respond to mechanical stimuli from the environment. In this review, we describe the technical and conceptual advances in the study of durotaxis in vitro, discuss to what extent the evidence suggests durotaxis may occur in vivo, and emphasize the urgent need for in vivo demonstration of durotaxis.
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Affiliation(s)
- Adam Shellard
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Roberto Mayor
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
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111
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Gross-Thebing S, Truszkowski L, Tenbrinck D, Sánchez-Iranzo H, Camelo C, Westerich KJ, Singh A, Maier P, Prengel J, Lange P, Hüwel J, Gaede F, Sasse R, Vos BE, Betz T, Matis M, Prevedel R, Luschnig S, Diz-Muñoz A, Burger M, Raz E. Using migrating cells as probes to illuminate features in live embryonic tissues. SCIENCE ADVANCES 2020; 6:eabc5546. [PMID: 33277250 PMCID: PMC7821905 DOI: 10.1126/sciadv.abc5546] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 10/21/2020] [Indexed: 05/03/2023]
Abstract
The biophysical and biochemical properties of live tissues are important in the context of development and disease. Methods for evaluating these properties typically involve destroying the tissue or require specialized technology and complicated analyses. Here, we present a novel, noninvasive methodology for determining the spatial distribution of tissue features within embryos, making use of nondirectionally migrating cells and software we termed "Landscape," which performs automatized high-throughput three-dimensional image registration. Using the live migrating cells as bioprobes, we identified structures within the zebrafish embryo that affect the distribution of the cells and studied one such structure constituting a physical barrier, which, in turn, influences amoeboid cell polarity. Overall, this work provides a unique approach for detecting tissue properties without interfering with animal's development. In addition, Landscape allows for integrating data from multiple samples, providing detailed and reliable quantitative evaluation of variable biological phenotypes in different organisms.
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Affiliation(s)
- Sargon Gross-Thebing
- Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
| | - Lukasz Truszkowski
- Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
| | - Daniel Tenbrinck
- Applied Mathematics Muenster, University of Muenster, Einsteinstr. 62, 48149 Muenster, Germany.
| | - Héctor Sánchez-Iranzo
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstr. 1, 69117 Heidelberg, Germany
| | - Carolina Camelo
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
- Institute of Animal Physiology, University of Muenster, Schlossplatz 8, 48143 Muenster, Germany
| | - Kim J Westerich
- Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
| | - Amrita Singh
- Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
| | - Paul Maier
- Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
| | - Jonas Prengel
- Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
| | - Pia Lange
- Applied Mathematics Muenster, University of Muenster, Einsteinstr. 62, 48149 Muenster, Germany
| | - Jan Hüwel
- Applied Mathematics Muenster, University of Muenster, Einsteinstr. 62, 48149 Muenster, Germany
| | - Fjedor Gaede
- Applied Mathematics Muenster, University of Muenster, Einsteinstr. 62, 48149 Muenster, Germany
| | - Ramona Sasse
- Applied Mathematics Muenster, University of Muenster, Einsteinstr. 62, 48149 Muenster, Germany
- Mathematics Muenster, University of Muenster, Einsteinstr. 62, 48149 Muenster, Germany
| | - Bart E Vos
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
- Mechanics of Cellular Systems Group, Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
| | - Timo Betz
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
- Mechanics of Cellular Systems Group, Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
| | - Maja Matis
- Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
| | - Robert Prevedel
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstr. 1, 69117 Heidelberg, Germany
| | - Stefan Luschnig
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
- Institute of Animal Physiology, University of Muenster, Schlossplatz 8, 48143 Muenster, Germany
| | - Alba Diz-Muñoz
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Meyerhofstr. 1, 69117 Heidelberg, Germany
| | - Martin Burger
- Applied Mathematics Muenster, University of Muenster, Einsteinstr. 62, 48149 Muenster, Germany
| | - Erez Raz
- Institute of Cell Biology, ZMBE, Von-Esmarch-Str. 56, 48149 Muenster, Germany.
- Cells in Motion (CiM) Interfaculty Center, 48149 Muenster, Germany
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112
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Pan Y, Zhang H, Xu P, Tian Y, Wang C, Xiang S, Boulatov R, Weng W. A Mechanochemical Reaction Cascade for Controlling Load-Strengthening of a Mechanochromic Polymer. Angew Chem Int Ed Engl 2020; 59:21980-21985. [PMID: 32827332 PMCID: PMC7756483 DOI: 10.1002/anie.202010043] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Indexed: 11/08/2022]
Abstract
We demonstrate an intermolecular reaction cascade to control the force which triggers crosslinking of a mechanochromic polymer of spirothiopyran (STP). Mechanochromism arises from rapid reversible force-sensitive isomerization of STP to a merocyanine, which reacts rapidly with activated C=C bonds. The concentration of such bonds, and hence the crosslinking rate, is controlled by force-dependent dissociation of a Diels-Alder adduct of anthracene and maleimide. Because the adduct requires ca. 1 nN higher force to dissociate at the same rate as that of STP isomerization, the cascade limits crosslinking to overstressed regions of the material, which are at the highest rate of material damage. Using comb polymers decreased the minimum concentration of mechanophores required to crosslinking by about 100-fold compared to previous examples of load-strengthening materials. The approach described has potential for controlling a broad range of reaction sequences triggered by mechanical load.
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Affiliation(s)
- Yifei Pan
- Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen University422 South Siming RoadXiamenFujian361005P. R. China
| | - Huan Zhang
- Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen University422 South Siming RoadXiamenFujian361005P. R. China
| | - Piaoxue Xu
- Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen University422 South Siming RoadXiamenFujian361005P. R. China
| | - Yancong Tian
- Department of ChemistryUniversity of Liverpool and Donnan LabG31, Crown St.LiverpoolL69 7ZDUK
| | - Chenxu Wang
- Department of ChemistryUniversity of Liverpool and Donnan LabG31, Crown St.LiverpoolL69 7ZDUK
| | - Shishuai Xiang
- Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen University422 South Siming RoadXiamenFujian361005P. R. China
| | - Roman Boulatov
- Department of ChemistryUniversity of Liverpool and Donnan LabG31, Crown St.LiverpoolL69 7ZDUK
| | - Wengui Weng
- Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen University422 South Siming RoadXiamenFujian361005P. R. China
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113
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Abstract
Magnetically actuated miniature soft robots are capable of programmable deformations for multimodal locomotion and manipulation functions, potentially enabling direct access to currently unreachable or difficult-to-access regions inside the human body for minimally invasive medical operations. However, magnetic miniature soft robots are so far mostly based on elastomers, where their limited deformability prevents them from navigating inside clustered and very constrained environments, such as squeezing through narrow crevices much smaller than the robot size. Moreover, their functionalities are currently restricted by their predesigned shapes, which is challenging to be reconfigured in situ in enclosed spaces. Here, we report a method to actuate and control ferrofluid droplets as shape-programmable magnetic miniature soft robots, which can navigate in two dimensions through narrow channels much smaller than their sizes thanks to their liquid properties. By controlling the external magnetic fields spatiotemporally, these droplet robots can also be reconfigured to exhibit multiple functionalities, including on-demand splitting and merging for delivering liquid cargos and morphing into different shapes for efficient and versatile manipulation of delicate objects. In addition, a single-droplet robot can be controlled to split into multiple subdroplets and complete cooperative tasks, such as working as a programmable fluidic-mixing device for addressable and sequential mixing of different liquids. Due to their extreme deformability, in situ reconfigurability and cooperative behavior, the proposed ferrofluid droplet robots could open up a wide range of unprecedented functionalities for lab/organ-on-a-chip, fluidics, bioengineering, and medical device applications.
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114
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Li Y, Chen M, Hu J, Sheng R, Lin Q, He X, Guo M. Volumetric Compression Induces Intracellular Crowding to Control Intestinal Organoid Growth via Wnt/β-Catenin Signaling. Cell Stem Cell 2020; 28:63-78.e7. [PMID: 33053374 DOI: 10.1016/j.stem.2020.09.012] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 02/26/2020] [Accepted: 09/14/2020] [Indexed: 12/14/2022]
Abstract
Enormous amounts of essential intracellular events are crowdedly packed inside picoliter-sized cellular space. However, the significance of the physical properties of cells remains underappreciated because of a lack of evidence of how they affect cellular functionalities. Here, we show that volumetric compression regulates the growth of intestinal organoids by modifying intracellular crowding and elevating Wnt/β-catenin signaling. Intracellular crowding varies upon stimulation by different types of extracellular physical/mechanical cues and leads to significant enhancement of Wnt/β-catenin signaling by stabilizing the LRP6 signalosome. By enhancing intracellular crowding using osmotic and mechanical compression, we show that expansion of intestinal organoids was facilitated through elevated Wnt/β-catenin signaling and greater intestinal stem cell (ISC) self-renewal. Our results provide an entry point for understanding how intracellular crowdedness functions as a physical regulator linking extracellular physical cues with intracellular signaling and potentially facilitate the design of engineering approaches for expansion of stem cells and organoids.
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Affiliation(s)
- Yiwei Li
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Maorong Chen
- F. M. Kirby Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jiliang Hu
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ren Sheng
- F. M. Kirby Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA; College of Life and Health Science, Northeastern University, Shenyang, Liaoning, 110004, China
| | - Qirong Lin
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Xi He
- F. M. Kirby Center, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Ming Guo
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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115
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Ort C, Lee W, Kalashnikov N, Moraes C. Disentangling the fibrous microenvironment: designer culture models for improved drug discovery. Expert Opin Drug Discov 2020; 16:159-171. [PMID: 32988224 DOI: 10.1080/17460441.2020.1822815] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
INTRODUCTION Standard high-throughput screening (HTS) assays rarely identify clinically viable 'hits', likely because cells do not experience physiologically realistic culture conditions. The biophysical nature of the extracellular matrix has emerged as a critical driver of cell function and response and recreating these factors could be critically important in streamlining the drug discovery pipeline. AREAS COVERED The authors review recent design strategies to understand and manipulate biophysical features of three-dimensional fibrous tissues. The effects of architectural parameters of the extracellular matrix and their resulting mechanical behaviors are deconstructed; and their individual and combined impact on cell behavior is examined. The authors then illustrate the potential impact of these physical features on designing next-generation platforms to identify drugs effective against breast cancer. EXPERT OPINION Progression toward increased culture complexity must be balanced against the demanding technical requirements for high-throughput screening; and strategies to identify the minimal set of microenvironmental parameters needed to recreate disease-relevant responses must be specifically tailored to the disease stage and organ system being studied. Although challenging, this can be achieved through integrative and multidisciplinary technologies that span microfabrication, cell biology, and tissue engineering.
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Affiliation(s)
- Carley Ort
- Department of Chemical Engineering, McGill University , Montreal, Canada
| | - Wontae Lee
- Department of Chemical Engineering, McGill University , Montreal, Canada
| | - Nikita Kalashnikov
- Department of Chemical Engineering, McGill University , Montreal, Canada
| | - Christopher Moraes
- Department of Chemical Engineering, McGill University , Montreal, Canada.,Department of Biomedical Engineering, McGill University , Montreal, Canada.,Rosalind & Morris Goodman Cancer Research Center, McGill University , Montreal, Canada
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116
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Pan Y, Zhang H, Xu P, Tian Y, Wang C, Xiang S, Boulatov R, Weng W. A Mechanochemical Reaction Cascade for Controlling Load‐Strengthening of a Mechanochromic Polymer. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202010043] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Yifei Pan
- Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University 422 South Siming Road Xiamen Fujian 361005 P. R. China
| | - Huan Zhang
- Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University 422 South Siming Road Xiamen Fujian 361005 P. R. China
| | - Piaoxue Xu
- Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University 422 South Siming Road Xiamen Fujian 361005 P. R. China
| | - Yancong Tian
- Department of Chemistry University of Liverpool and Donnan Lab G31, Crown St. Liverpool L69 7ZD UK
| | - Chenxu Wang
- Department of Chemistry University of Liverpool and Donnan Lab G31, Crown St. Liverpool L69 7ZD UK
| | - Shishuai Xiang
- Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University 422 South Siming Road Xiamen Fujian 361005 P. R. China
| | - Roman Boulatov
- Department of Chemistry University of Liverpool and Donnan Lab G31, Crown St. Liverpool L69 7ZD UK
| | - Wengui Weng
- Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University 422 South Siming Road Xiamen Fujian 361005 P. R. China
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117
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Mok S, Al Habyan S, Ledoux C, Lee W, MacDonald KN, McCaffrey L, Moraes C. Mapping cellular-scale internal mechanics in 3D tissues with thermally responsive hydrogel probes. Nat Commun 2020; 11:4757. [PMID: 32958771 PMCID: PMC7505969 DOI: 10.1038/s41467-020-18469-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 08/25/2020] [Indexed: 02/07/2023] Open
Abstract
Local tissue mechanics play a critical role in cell function, but measuring these properties at cellular length scales in living 3D tissues can present considerable challenges. Here we present thermoresponsive, smart material microgels that can be dispersed or injected into tissues and optically assayed to measure residual tissue elasticity after creep over several weeks. We first develop and characterize the sensors, and demonstrate that internal mechanical profiles of live multicellular spheroids can be mapped at high resolutions to reveal broad ranges of rigidity within the tissues, which vary with subtle differences in spheroid aggregation method. We then show that small sites of unexpectedly high rigidity develop in invasive breast cancer spheroids, and in an in vivo mouse model of breast cancer progression. These focal sites of increased intratumoral rigidity suggest new possibilities for how early mechanical cues that drive cancer cells towards invasion might arise within the evolving tumor microenvironment.
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Affiliation(s)
- Stephanie Mok
- Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, QC, H3A 0C5, Canada
| | - Sara Al Habyan
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, 160 Pine Ave W, Montreal, QC, H3A 1A3, Canada
| | - Charles Ledoux
- Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, QC, H3A 0C5, Canada
| | - Wontae Lee
- Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, QC, H3A 0C5, Canada
| | - Katherine N MacDonald
- Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, QC, H3A 0C5, Canada
| | - Luke McCaffrey
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, 160 Pine Ave W, Montreal, QC, H3A 1A3, Canada
| | - Christopher Moraes
- Department of Chemical Engineering, McGill University, 3610 University Street, Montreal, QC, H3A 0C5, Canada.
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, 160 Pine Ave W, Montreal, QC, H3A 1A3, Canada.
- Department of Biomedical Engineering, McGill University, 3775 University Street, Montreal, QC, H3A 2B4, Canada.
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118
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Lim I, Vian A, van de Wouw HL, Day RA, Gomez C, Liu Y, Rheingold AL, Campàs O, Sletten EM. Fluorous Soluble Cyanine Dyes for Visualizing Perfluorocarbons in Living Systems. J Am Chem Soc 2020; 142:16072-16081. [PMID: 32808518 PMCID: PMC8366720 DOI: 10.1021/jacs.0c07761] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The bioorthogonal nature of perfluorocarbons provides a unique platform for introducing dynamic nano- and microdroplets into cells and organisms. To monitor the localization and deformation of the droplets, fluorous soluble fluorophores that are compatible with standard fluorescent protein markers and applicable to cells, tissues, and small organisms are necessary. Here, we introduce fluorous cyanine dyes that represent the most red-shifted fluorous soluble fluorophores to date. We study the effect of covalently appended fluorous tags on the cyanine scaffold and evaluate the changes in photophysical properties imparted by the fluorous phase. Ultimately, we showcase the utility of the fluorous soluble pentamethine cyanine dye for tracking the localization of perfluorocarbon nanoemulsions in macrophage cells and for measurements of mechanical forces in multicellular spheroids and zebrafish embryonic tissues. These studies demonstrate that the red-shifted cyanine dyes offer spectral flexibility in multiplexed imaging experiments and enhanced precision in force measurements.
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Affiliation(s)
- Irene Lim
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Antoine Vian
- Department of Mechanical Engineering, University of California, Santa Barbara, California 93106-5200, United States
| | - Heidi L. van de Wouw
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Rachael A. Day
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
| | - Carlos Gomez
- Department of Mechanical Engineering, University of California, Santa Barbara, California 93106-5200, United States
| | - Yucen Liu
- Department of Mechanical Engineering, University of California, Santa Barbara, California 93106-5200, United States
| | - Arnold L. Rheingold
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093-0505, United States
| | - Otger Campàs
- Department of Mechanical Engineering, University of California, Santa Barbara, California 93106-5200, United States
| | - Ellen M. Sletten
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095-1569, United States
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119
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Mechanical Coupling Coordinates the Co-elongation of Axial and Paraxial Tissues in Avian Embryos. Dev Cell 2020; 55:354-366.e5. [PMID: 32918876 DOI: 10.1016/j.devcel.2020.08.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 06/03/2020] [Accepted: 08/17/2020] [Indexed: 01/20/2023]
Abstract
Tissues undergoing morphogenesis impose mechanical effects on one another. How developmental programs adapt to or take advantage of these effects remains poorly explored. Here, using a combination of live imaging, modeling, and microsurgical perturbations, we show that the axial and paraxial tissues in the forming avian embryonic body coordinate their rates of elongation through mechanical interactions. First, a cell motility gradient drives paraxial presomitic mesoderm (PSM) expansion, resulting in compression of the axial neural tube and notochord; second, elongation of axial tissues driven by PSM compression and polarized cell intercalation pushes the caudal progenitor domain posteriorly; finally, the axial push drives the lateral movement of midline PSM cells to maintain PSM growth and cell motility. These interactions form an engine-like positive feedback loop, which sustains a shared elongation rate for coupled tissues. Our results demonstrate a key role of inter-tissue forces in coordinating distinct body axis tissues during their co-elongation.
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120
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Tlili S, Durande M, Gay C, Ladoux B, Graner F, Delanoë-Ayari H. Migrating Epithelial Monolayer Flows Like a Maxwell Viscoelastic Liquid. PHYSICAL REVIEW LETTERS 2020; 125:088102. [PMID: 32909763 DOI: 10.1103/physrevlett.125.088102] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/16/2020] [Indexed: 06/11/2023]
Abstract
We perform a bidimensional Stokes experiment in an active cellular material: an autonomously migrating monolayer of Madin-Darby canine kidney epithelial cells flows around a circular obstacle within a long and narrow channel, involving an interplay between cell shape changes and neighbor rearrangements. Based on image analysis of tissue flow and coarse-grained cell anisotropy, we determine the tissue strain rate, cell deformation, and rearrangement rate fields, which are spatially heterogeneous. We find that the cell deformation and rearrangement rate fields correlate strongly, which is compatible with a Maxwell viscoelastic liquid behavior (and not with a Kelvin-Voigt viscoelastic solid behavior). The value of the associated relaxation time is measured as τ=70±15 min, is observed to be independent of obstacle size and division rate, and is increased by inhibiting myosin activity. In this experiment, the monolayer behaves as a flowing material with a Weissenberg number close to one which shows that both elastic and viscous effects can have comparable contributions in the process of collective cell migration.
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Affiliation(s)
- S Tlili
- Laboratoire Matière et Systèmes Complexes, Université de Paris-Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13, France
- Mechanobiology Institute, Department of Biological Sciences, National University of Singapore, 5A Engineering Drive, 1, 117411 Singapore
| | - M Durande
- Laboratoire Matière et Systèmes Complexes, Université de Paris-Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13, France
| | - C Gay
- Laboratoire Matière et Systèmes Complexes, Université de Paris-Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13, France
| | - B Ladoux
- Mechanobiology Institute, Department of Biological Sciences, National University of Singapore, 5A Engineering Drive, 1, 117411 Singapore
- Institut Jacques Monod, Université de Paris-Diderot, CNRS UMR 7592, 15 rue Hélène Brion, 75205 Paris Cedex 13, France
| | - F Graner
- Laboratoire Matière et Systèmes Complexes, Université de Paris-Diderot, CNRS UMR 7057, 10 rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13, France
| | - H Delanoë-Ayari
- Univ. Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5306, Institut Lumière Matière, Campus LyonTech-La Doua, Kastler building, 10 rue Ada Byron, F-69622 Villeurbanne Cedex, France
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121
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Hirashima T. Mechanical Tissue Compression and Whole-mount Imaging at Single CellResolution for Developing Murine Epididymal Tubules. Bio Protoc 2020; 10:e3694. [PMID: 33659362 DOI: 10.21769/bioprotoc.3694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 05/19/2020] [Accepted: 05/21/2020] [Indexed: 11/02/2022] Open
Abstract
Cells inside the body are subjected to various mechanical stress, such as stretch or compression provided by surrounding cells, shear stresses by blood or lymph flows, and normal stresses by luminal liquids. Force loading to the biological tissues is a fundamental method to better understand cellular responses to such mechanical stimuli. There have been many studies on compression or stretch experiments that target culture cells attached to a flexible extensible material including polydimethylsiloxane (PDMS); however, the know-how of those targeting to tissues is still incomplete. Here we present the protocol for mechanical tissue compression and image-based analysis by focusing on developing murine epididymis as an example. We show a series of steps including tissue dissection from murine embryos, hydrogel-based compression method using a manual device, and non-destructive volumetric tissue imaging. This protocol is useful for quantifying and exploring the biological mechanoresponse system at tissue level.
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Affiliation(s)
- Tsuyoshi Hirashima
- Department of Pathology and Biology of Diseases, Graduate School of Medicine, Kyoto University, Kyoto, Japan.,Japan Science and Technology Agency, PRESTO, Sakyo-ku, Kyoto, Japan
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122
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Chu CW, Masak G, Yang J, Davidson LA. From biomechanics to mechanobiology: Xenopus provides direct access to the physical principles that shape the embryo. Curr Opin Genet Dev 2020; 63:71-77. [PMID: 32563783 PMCID: PMC9972463 DOI: 10.1016/j.gde.2020.05.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 05/01/2020] [Accepted: 05/06/2020] [Indexed: 11/28/2022]
Abstract
Features of amphibian embryos that have served so well to elucidate the genetics of vertebrate development also enable detailed analysis of the physics that shape morphogenesis and regulate development. Biophysical tools are revealing how genes control mechanical properties of the embryo. The same tools that describe and control mechanical properties are being turned to reveal how dynamic mechanical information and feedback regulate biological programs of development. In this review we outline efforts to explore the various roles of mechanical cues in guiding cilia biology, axonal pathfinding, goblet cell regeneration, epithelial-to-mesenchymal transitions in neural crest, and mesenchymal-to-epithelial transitions in heart progenitors. These case studies reveal the power of Xenopus experimental embryology to expose pathways integrating mechanical cues with programs of development, organogenesis, and regeneration.
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Affiliation(s)
- Chih-Wen Chu
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA.
| | - Geneva Masak
- Integrated Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Jing Yang
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA
| | - Lance A Davidson
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15260, USA; Integrative Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA; Department of Developmental Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA; Department of Computational and Systems Biology, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15260, USA.
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123
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Gillard G, Röper K. Control of cell shape during epithelial morphogenesis: recent advances. Curr Opin Genet Dev 2020; 63:1-8. [PMID: 32092616 DOI: 10.1016/j.gde.2020.01.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 01/15/2020] [Accepted: 01/20/2020] [Indexed: 01/07/2023]
Abstract
Morphogenesis is an essential process by which a given tissue, organ or organism acquires its final shape. A select number of mechanisms are used in order to drive epithelial morphogenesis, including cell shape changes as well as cell death or cell division. A cell's shape results from the combination of intrinsic properties of the actomyosin and microtubule (MTs) cytoskeletons, and extrinsic properties due to physical interactions with the neighbouring environment. While we now have a good understanding of the genetic pathways and some of the signalling pathways controlling cell shape changes, the mechanical properties of cells and their role in morphogenesis remain largely unexplored. Recent improvements in microscopy techniques and the development of modelling and quantitative methods have enabled a better understanding of the bio-mechanical events controlling cell shape during morphogenesis. This review aims to highlight recent findings elegantly unravelling and quantifying the contribution of mechanical forces during morphogenesis.
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Affiliation(s)
- Ghislain Gillard
- MRC-Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
| | - Katja Röper
- MRC-Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge CB2 0QH, UK.
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124
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Tay A. The Benefits of Going Small: Nanostructures for Mammalian Cell Transfection. ACS NANO 2020; 14:7714-7721. [PMID: 32631053 DOI: 10.1021/acsnano.0c04624] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Nanostructures, with their localized interactions with mammalian cells, can offer better efficiency and lower cell perturbation than conventional viral, biochemical, and electroporation transfection techniques. In this Perspective, I describe the different stages of transfection and provide a comparison of transfection techniques based on their mechanisms. Focusing on specific aims of transfection, I also illustrate how recent developments in high-aspect-ratio nanostructures have endowed them with properties that are superior to existing viral, biochemical, and electroporation methods as a versatile technique to deliver a variety of cargoes and to interface with different mammalian cell types for biomedical applications. Finally, I describe the challenges associated with transfection that need to be overcome to enhance cargo delivery efficiency and clinical translation.
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Affiliation(s)
- Andy Tay
- Department of Biomedical Engineering, National University of Singapore, Singapore 117583
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125
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Bonfanti A, Kaplan JL, Charras G, Kabla A. Fractional viscoelastic models for power-law materials. SOFT MATTER 2020; 16:6002-6020. [PMID: 32638812 DOI: 10.1039/d0sm00354a] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Soft materials often exhibit a distinctive power-law viscoelastic response arising from broad distribution of time-scales present in their complex internal structure. A promising tool to accurately describe the rheological behaviour of soft materials is fractional calculus. However, its use in the scientific community remains limited due to the unusual notation and non-trivial properties of fractional operators. This review aims to provide a clear and accessible description of fractional viscoelastic models for a broad audience and to demonstrate the ability of these models to deliver a unified approach for the characterisation of power-law materials. The use of a consistent framework for the analysis of rheological data would help classify the empirical behaviours of soft and biological materials, and better understand their response.
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Affiliation(s)
- A Bonfanti
- Department of Engineering, University of Cambridge, UK.
| | - J L Kaplan
- Department of Engineering, University of Cambridge, UK.
| | - G Charras
- London Centre for Nanotechnology, University College London, UK and Department of Cell and Developmental Biology, University College London, UK
| | - A Kabla
- Department of Engineering, University of Cambridge, UK.
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126
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Herrera-Perez RM, Kasza KE. Manipulating the Patterns of Mechanical Forces That Shape Multicellular Tissues. Physiology (Bethesda) 2020; 34:381-391. [PMID: 31577169 DOI: 10.1152/physiol.00018.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
During embryonic development, spatial and temporal patterns of mechanical forces help to transform unstructured groups of cells into complex, functional tissue architectures. Here, we review emerging approaches to manipulate these patterns of forces to investigate the mechanical mechanisms that shape multicellular tissues, with a focus on recent experimental studies of epithelial tissue sheets in the embryo of the model organism Drosophila melanogaster.
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Affiliation(s)
| | - Karen E Kasza
- Department of Mechanical Engineering, Columbia University, New York, New York
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127
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Wang X, Merkel M, Sutter LB, Erdemci-Tandogan G, Manning ML, Kasza KE. Anisotropy links cell shapes to tissue flow during convergent extension. Proc Natl Acad Sci U S A 2020; 117:13541-13551. [PMID: 32467168 PMCID: PMC7306759 DOI: 10.1073/pnas.1916418117] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Within developing embryos, tissues flow and reorganize dramatically on timescales as short as minutes. This includes epithelial tissues, which often narrow and elongate in convergent extension movements due to anisotropies in external forces or in internal cell-generated forces. However, the mechanisms that allow or prevent tissue reorganization, especially in the presence of strongly anisotropic forces, remain unclear. We study this question in the converging and extending Drosophila germband epithelium, which displays planar-polarized myosin II and experiences anisotropic forces from neighboring tissues. We show that, in contrast to isotropic tissues, cell shape alone is not sufficient to predict the onset of rapid cell rearrangement. From theoretical considerations and vertex model simulations, we predict that in anisotropic tissues, two experimentally accessible metrics of cell patterns-the cell shape index and a cell alignment index-are required to determine whether an anisotropic tissue is in a solid-like or fluid-like state. We show that changes in cell shape and alignment over time in the Drosophila germband predict the onset of rapid cell rearrangement in both wild-type and snail twist mutant embryos, where our theoretical prediction is further improved when we also account for cell packing disorder. These findings suggest that convergent extension is associated with a transition to more fluid-like tissue behavior, which may help accommodate tissue-shape changes during rapid developmental events.
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Affiliation(s)
- Xun Wang
- Department of Mechanical Engineering, Columbia University, New York, NY 10027
| | - Matthias Merkel
- Department of Physics, Syracuse University, Syracuse, NY 13244
- BioInspired Institute, Syracuse University, Syracuse, NY 13244
- Centre de Physique Théorique (CPT), Turing Center for Living Systems, Aix Marseille Univ, Université de Toulon, CNRS, 13009 Marseille, France
| | - Leo B Sutter
- Department of Physics, Syracuse University, Syracuse, NY 13244
- BioInspired Institute, Syracuse University, Syracuse, NY 13244
| | - Gonca Erdemci-Tandogan
- Department of Physics, Syracuse University, Syracuse, NY 13244
- BioInspired Institute, Syracuse University, Syracuse, NY 13244
| | - M Lisa Manning
- Department of Physics, Syracuse University, Syracuse, NY 13244
- BioInspired Institute, Syracuse University, Syracuse, NY 13244
| | - Karen E Kasza
- Department of Mechanical Engineering, Columbia University, New York, NY 10027;
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128
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Abstract
As the crucial non-cellular component of tissues, the extracellular matrix (ECM) provides both physical support and signaling regulation to cells. Some ECM molecules provide a fibrillar environment around cells, while others provide a sheet-like basement membrane scaffold beneath epithelial cells. In this Review, we focus on recent studies investigating the mechanical, biophysical and signaling cues provided to developing tissues by different types of ECM in a variety of developing organisms. In addition, we discuss how the ECM helps to regulate tissue morphology during embryonic development by governing key elements of cell shape, adhesion, migration and differentiation. Summary: This Review discusses our current understanding of how the extracellular matrix helps guide developing tissues by influencing cell adhesion, migration, shape and differentiation, emphasizing the biophysical cues it provides.
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Affiliation(s)
- David A Cruz Walma
- Cell Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892-4370, USA
| | - Kenneth M Yamada
- Cell Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, 20892-4370, USA
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129
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Kaytanlı B, Khankhel AH, Cohen N, Valentine MT. Rapid analysis of cell-generated forces within a multicellular aggregate using microsphere-based traction force microscopy. SOFT MATTER 2020; 16:4192-4199. [PMID: 32286589 DOI: 10.1039/c9sm02377a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We present a new approach to measuring cell-generated forces from the deformations of elastic microspheres embedded within multicellular aggregates. By directly fitting the measured sensor deformation to an analytical model based on experimental observations and invoking linear elasticity, we dramatically reduce the computational complexity of the problem, and directly obtain the full 3D mapping of surface stresses. Our approach imparts extraordinary computational efficiency, allowing tractions to be estimated within minutes and enabling rapid analysis of microsphere-based traction force microscopy data.
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Affiliation(s)
- Buğra Kaytanlı
- Department of Mechanical Engineering, University of California, Santa Barbara, CA 93106, USA.
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130
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D'Angelo A, Solon J. Application of Mechanical Forces on Drosophila Embryos by Manipulation of Microinjected Magnetic Particles. Bio Protoc 2020; 10:e3608. [PMID: 33659573 DOI: 10.21769/bioprotoc.3608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Revised: 02/13/2020] [Accepted: 02/23/2020] [Indexed: 11/02/2022] Open
Abstract
Cells generate mechanical forces to shape tissues during morphogenesis. These forces can activate several biochemical pathways and trigger diverse cellular responses by mechano-sensation, such as differentiation, division, migration and apoptosis. Assessing the mechano-responses of cells in living organisms requires tools to apply controlled local forces within biological tissues. For this, we have set up a method to generate controlled forces on a magnetic particle embedded within a chosen tissue of Drosophila embryos. We designed a protocol to inject an individual particle in early embryos and to position it, using a permanent magnet, within the tissue of our choice. Controlled forces in the range of pico to nanonewtons can be applied on the particle with the use of an electromagnet that has been previously calibrated. The bead displacement and the epithelial deformation upon force application can be followed with live imaging and further analyzed using simple analysis tools. This method has been successfully used to identify changes in mechanics in the blastoderm before gastrulation. This protocol provides the details, (i) for injecting a magnetic particle in Drosophila embryos, (ii) for calibrating an electromagnet and (iii) to apply controlled forces in living tissues.
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Affiliation(s)
- Arturo D'Angelo
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain
| | - Jérôme Solon
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, 08003 Barcelona, Spain.,Universitat Pompeu Fabra (UPF), 08003 Barcelona, Spain.,Instituto Biofisika (UPV/EHU, CSIC), University of the Basque Country and Fundación Biofisica Bizkaia/Biofisika Fundazioa (FBB), 48940 Leioa, Spain.,Ikerbasque, Basque Foundation for Science, 48013 Bilbao, Spain
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131
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Leonard CE, Taneyhill LA. The road best traveled: Neural crest migration upon the extracellular matrix. Semin Cell Dev Biol 2020; 100:177-185. [PMID: 31727473 PMCID: PMC7071992 DOI: 10.1016/j.semcdb.2019.10.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Revised: 09/29/2019] [Accepted: 10/30/2019] [Indexed: 12/22/2022]
Abstract
Neural crest cells have the extraordinary task of building much of the vertebrate body plan, including the craniofacial cartilage and skeleton, melanocytes, portions of the heart, and the peripheral nervous system. To execute these developmental programs, stationary premigratory neural crest cells first acquire the capacity to migrate through an extensive process known as the epithelial-to-mesenchymal transition. Once motile, neural crest cells must traverse a complex environment consisting of other cells and the protein-rich extracellular matrix in order to get to their final destinations. Herein, we will highlight some of the main molecular machinery that allow neural crest cells to first exit the neuroepithelium and then later successfully navigate this intricate in vivo milieu. Collectively, these extracellular and intracellular factors mediate the appropriate migration of neural crest cells and allow for the proper development of the vertebrate embryo.
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Affiliation(s)
- Carrie E Leonard
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD 20742 USA.
| | - Lisa A Taneyhill
- Department of Animal and Avian Sciences, University of Maryland, College Park, MD 20742 USA.
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132
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Nerger BA, Nelson CM. Engineered extracellular matrices: emerging strategies for decoupling structural and molecular signals that regulate epithelial branching morphogenesis. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2020; 13:103-112. [PMID: 32864528 PMCID: PMC7451493 DOI: 10.1016/j.cobme.2019.12.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The extracellular matrix (ECM) is a heterogeneous mixture of proteoglycans and fibrous proteins that form the non-cellular component of tissues and organs. During normal development, homeostasis, and disease progression, the ECM provides dynamic structural and molecular signals that influence the form and function of individual cells and multicellular tissues. Here, we review recent developments in the design and fabrication of engineered ECMs and the application of these systems to study the morphogenesis of epithelial tissues. We emphasize emerging techniques for reproducing the structural and molecular complexity of native ECM, and we highlight how these techniques may be used to decouple the different signals that drive epithelial morphogenesis. Engineered models of native ECM will enable further investigation of the dynamic mechanisms by which the microenvironment influences tissue morphogenesis.
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Affiliation(s)
- Bryan A. Nerger
- Department of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544
| | - Celeste M. Nelson
- Department of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544
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133
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Spatial mapping of tissue properties in vivo reveals a 3D stiffness gradient in the mouse limb bud. Proc Natl Acad Sci U S A 2020; 117:4781-4791. [PMID: 32071242 DOI: 10.1073/pnas.1912656117] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Numerous hypotheses invoke tissue stiffness as a key parameter that regulates morphogenesis and disease progression. However, current methods are insufficient to test hypotheses that concern physical properties deep in living tissues. Here we introduce, validate, and apply a magnetic device that generates a uniform magnetic field gradient within a space that is sufficient to accommodate an organ-stage mouse embryo under live conditions. The method allows rapid, nontoxic measurement of the three-dimensional (3D) spatial distribution of viscoelastic properties within mesenchyme and epithelia. Using the device, we identify an anteriorly biased mesodermal stiffness gradient along which cells move to shape the early limb bud. The stiffness gradient corresponds to a Wnt5a-dependent domain of fibronectin expression, raising the possibility that durotaxis underlies cell movements. Three-dimensional stiffness mapping enables the generation of hypotheses and potentially the rigorous testing of mechanisms of development and disease.
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134
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Vorselen D, Wang Y, de Jesus MM, Shah PK, Footer MJ, Huse M, Cai W, Theriot JA. Microparticle traction force microscopy reveals subcellular force exertion patterns in immune cell-target interactions. Nat Commun 2020; 11:20. [PMID: 31911639 PMCID: PMC6946705 DOI: 10.1038/s41467-019-13804-z] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 11/18/2019] [Indexed: 01/11/2023] Open
Abstract
Force exertion is an integral part of cellular behavior. Traction force microscopy (TFM) has been instrumental for studying such forces, providing spatial force measurements at subcellular resolution. However, the applications of classical TFM are restricted by the typical planar geometry. Here, we develop a particle-based force sensing strategy for studying cellular interactions. We establish a straightforward batch approach for synthesizing uniform, deformable and tuneable hydrogel particles, which can also be easily derivatized. The 3D shape of such particles can be resolved with superresolution (<50 nm) accuracy using conventional confocal microscopy. We introduce a reference-free computational method allowing inference of traction forces with high sensitivity directly from the particle shape. We illustrate the potential of this approach by revealing subcellular force patterns throughout phagocytic engulfment and force dynamics in the cytotoxic T-cell immunological synapse. This strategy can readily be adapted for studying cellular forces in a wide range of applications.
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Affiliation(s)
- Daan Vorselen
- Department of Biochemistry, Stanford University, Stanford, CA, 94305, USA
- Department of Biology and Howard Hughes Medical Institute, University of Washington, Seattle, WA, 98105, USA
| | - Yifan Wang
- Department of Mechanical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Miguel M de Jesus
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Pavak K Shah
- Developmental Biology Program, Sloan Kettering Institute, New York, NY, 10065, USA
| | - Matthew J Footer
- Department of Biochemistry, Stanford University, Stanford, CA, 94305, USA
- Department of Biology and Howard Hughes Medical Institute, University of Washington, Seattle, WA, 98105, USA
| | - Morgan Huse
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, 10065, USA
| | - Wei Cai
- Department of Mechanical Engineering, Stanford University, Stanford, CA, 94305, USA
| | - Julie A Theriot
- Department of Biochemistry, Stanford University, Stanford, CA, 94305, USA.
- Department of Biology and Howard Hughes Medical Institute, University of Washington, Seattle, WA, 98105, USA.
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135
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Zhu M, Zhang K, Tao H, Hopyan S, Sun Y. Magnetic Micromanipulation for In Vivo Measurement of Stiffness Heterogeneity and Anisotropy in the Mouse Mandibular Arch. RESEARCH (WASHINGTON, D.C.) 2020; 2020:7914074. [PMID: 32666052 PMCID: PMC7327709 DOI: 10.34133/2020/7914074] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/20/2020] [Indexed: 12/14/2022]
Abstract
The mechanical properties of tissues are pivotal for morphogenesis and disease progression. Recent approaches have enabled measurements of the spatial distributions of viscoelastic properties among embryonic and pathological model systems and facilitated the generation of important hypotheses such as durotaxis and tissue-scale phase transition. There likely are many unexpected aspects of embryo biomechanics we have yet to discover which will change our views of mechanisms that govern development and disease. One area in the blind spot of even the most recent approaches to measuring tissue stiffness is the potentially anisotropic nature of that parameter. Here, we report a magnetic micromanipulation device that generates a uniform magnetic field gradient within a large workspace and permits measurement of the variation of tissue stiffness along three orthogonal axes. By applying the device to the organ-stage mouse embryo, we identify spatially heterogenous and directionally anisotropic stiffness within the mandibular arch. Those properties correspond to the domain of expression and the angular distribution of fibronectin and have potential implications for mechanisms that orient collective cell movements and shape tissues during development. Assessment of anisotropic properties extends the repertoire of current methods and will enable the generation and testing of hypotheses.
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Affiliation(s)
- Min Zhu
- Department of Mechanical and Industrial Engineering, University of Toronto, Canada M5S 3G8
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, ON, Canada M5G 0A4
| | - Kaiwen Zhang
- Department of Mechanical and Industrial Engineering, University of Toronto, Canada M5S 3G8
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, ON, Canada M5G 0A4
| | - Hirotaka Tao
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, ON, Canada M5G 0A4
| | - Sevan Hopyan
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, ON, Canada M5G 0A4
- Department of Molecular Genetics, University of Toronto, Canada M5S 1A8
- Division of Orthopaedic Surgery, The Hospital for Sick Children and University of Toronto, Canada M5G 1X8
| | - Yu Sun
- Department of Mechanical and Industrial Engineering, University of Toronto, Canada M5S 3G8
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Canada M5S 3G9
- Department of Electrical and Computer Engineering, University of Toronto, Canada M5S 3G4
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136
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Bonfanti A, Fouchard J, Khalilgharibi N, Charras G, Kabla A. A unified rheological model for cells and cellularised materials. ROYAL SOCIETY OPEN SCIENCE 2020; 7:190920. [PMID: 32218933 PMCID: PMC7029884 DOI: 10.1098/rsos.190920] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 11/22/2019] [Indexed: 05/04/2023]
Abstract
The mechanical response of single cells and tissues exhibits a broad distribution of time-scales that often gives rise to a distinctive power-law rheology. Such complex behaviour cannot be easily captured by traditional rheological approaches, making material characterisation and predictive modelling very challenging. Here, we present a novel model combining conventional viscoelastic elements with fractional calculus that successfully captures the macroscopic relaxation response of epithelial monolayers. The parameters extracted from the fitting of the relaxation modulus allow prediction of the response of the same material to slow stretch and creep, indicating that the model captured intrinsic material properties. Two characteristic times, derived from the model parameters, delimit different regimes in the materials response. We compared the response of tissues with the behaviour of single cells as well as intra and extra-cellular components, and linked the power-law behaviour of the epithelium to the dynamics of the cell cortex. Such a unified model for the mechanical response of biological materials provides a novel and robust mathematical approach to consistently analyse experimental data and uncover similarities and differences in reported behaviour across experimental methods and research groups. It also sets the foundations for more accurate computational models of tissue mechanics.
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Affiliation(s)
- A. Bonfanti
- Engineering Department, Cambridge University, Cambridge, UK
| | - J. Fouchard
- London Centre for Nanotechnology, University College London, London, UK
| | - N. Khalilgharibi
- London Centre for Nanotechnology, University College London, London, UK
- The Centre for Computation, Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), University College London, London, UK
| | - G. Charras
- London Centre for Nanotechnology, University College London, London, UK
- Institute for the Physics of Living Systems, University College London, London, UK
- Department of Cell and Developmental Biology, University College London, London, UK
| | - A. Kabla
- Engineering Department, Cambridge University, Cambridge, UK
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137
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Bonfanti A, Fouchard J, Khalilgharibi N, Charras G, Kabla A. A unified rheological model for cells and cellularised materials. ROYAL SOCIETY OPEN SCIENCE 2020. [PMID: 32218933 DOI: 10.5061/dryad.s853qg7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The mechanical response of single cells and tissues exhibits a broad distribution of time-scales that often gives rise to a distinctive power-law rheology. Such complex behaviour cannot be easily captured by traditional rheological approaches, making material characterisation and predictive modelling very challenging. Here, we present a novel model combining conventional viscoelastic elements with fractional calculus that successfully captures the macroscopic relaxation response of epithelial monolayers. The parameters extracted from the fitting of the relaxation modulus allow prediction of the response of the same material to slow stretch and creep, indicating that the model captured intrinsic material properties. Two characteristic times, derived from the model parameters, delimit different regimes in the materials response. We compared the response of tissues with the behaviour of single cells as well as intra and extra-cellular components, and linked the power-law behaviour of the epithelium to the dynamics of the cell cortex. Such a unified model for the mechanical response of biological materials provides a novel and robust mathematical approach to consistently analyse experimental data and uncover similarities and differences in reported behaviour across experimental methods and research groups. It also sets the foundations for more accurate computational models of tissue mechanics.
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Affiliation(s)
- A Bonfanti
- Engineering Department, Cambridge University, Cambridge, UK
| | - J Fouchard
- London Centre for Nanotechnology, University College London, London, UK
| | - N Khalilgharibi
- London Centre for Nanotechnology, University College London, London, UK
- The Centre for Computation, Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), University College London, London, UK
| | - G Charras
- London Centre for Nanotechnology, University College London, London, UK
- Institute for the Physics of Living Systems, University College London, London, UK
- Department of Cell and Developmental Biology, University College London, London, UK
| | - A Kabla
- Engineering Department, Cambridge University, Cambridge, UK
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138
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Zhang J, Chada NC, Reinhart-King CA. Microscale Interrogation of 3D Tissue Mechanics. Front Bioeng Biotechnol 2019; 7:412. [PMID: 31921816 PMCID: PMC6927918 DOI: 10.3389/fbioe.2019.00412] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Accepted: 11/28/2019] [Indexed: 01/02/2023] Open
Abstract
Cells in vivo live in a complex microenvironment composed of the extracellular matrix (ECM) and other cells. Growing evidence suggests that the mechanical interaction between the cells and their microenvironment is of critical importance to their behaviors under both normal and diseased conditions, such as migration, differentiation, and proliferation. The study of tissue mechanics in the past two decades, including the assessment of both mechanical properties and mechanical stresses of the extracellular microenvironment, has greatly enriched our knowledge about how cells interact with their mechanical environment. Tissue mechanical properties are often heterogeneous and sometimes anisotropic, which makes them difficult to obtain from macroscale bulk measurements. Mechanical stresses were first measured for cells cultured on two-dimensional (2D) surfaces with well-defined mechanical properties. While 2D measurements are relatively straightforward and efficient, and they have provided us with valuable knowledge on cell-ECM interactions, that knowledge may not be directly applicable to in vivo systems. Hence, the measurement of tissue stresses in a more physiologically relevant three-dimensional (3D) environment is required. In this mini review, we will summarize and discuss recent developments in using optical, magnetic, genetic, and mechanical approaches to interrogate 3D tissue stresses and mechanical properties at the microscale.
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139
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Quinn PM, Wijnholds J. Retinogenesis of the Human Fetal Retina: An Apical Polarity Perspective. Genes (Basel) 2019; 10:E987. [PMID: 31795518 PMCID: PMC6947654 DOI: 10.3390/genes10120987] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 11/25/2019] [Accepted: 11/26/2019] [Indexed: 12/20/2022] Open
Abstract
The Crumbs complex has prominent roles in the control of apical cell polarity, in the coupling of cell density sensing to downstream cell signaling pathways, and in regulating junctional structures and cell adhesion. The Crumbs complex acts as a conductor orchestrating multiple downstream signaling pathways in epithelial and neuronal tissue development. These pathways lead to the regulation of cell size, cell fate, cell self-renewal, proliferation, differentiation, migration, mitosis, and apoptosis. In retinogenesis, these are all pivotal processes with important roles for the Crumbs complex to maintain proper spatiotemporal cell processes. Loss of Crumbs function in the retina results in loss of the stratified appearance resulting in retinal degeneration and loss of visual function. In this review, we begin by discussing the physiology of vision. We continue by outlining the processes of retinogenesis and how well this is recapitulated between the human fetal retina and human embryonic stem cell (ESC) or induced pluripotent stem cell (iPSC)-derived retinal organoids. Additionally, we discuss the functionality of in utero and preterm human fetal retina and the current level of functionality as detected in human stem cell-derived organoids. We discuss the roles of apical-basal cell polarity in retinogenesis with a focus on Leber congenital amaurosis which leads to blindness shortly after birth. Finally, we discuss Crumbs homolog (CRB)-based gene augmentation.
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Affiliation(s)
- Peter M.J. Quinn
- Department of Ophthalmology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands;
| | - Jan Wijnholds
- Department of Ophthalmology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands;
- The Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences, 1105 BA Amsterdam, The Netherlands
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140
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Loerke D, Blankenship JT. Viscoelastic voyages - Biophysical perspectives on cell intercalation during Drosophila gastrulation. Semin Cell Dev Biol 2019; 100:212-222. [PMID: 31784092 DOI: 10.1016/j.semcdb.2019.11.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 09/11/2019] [Accepted: 11/11/2019] [Indexed: 12/18/2022]
Abstract
Developmental processes are driven by a combination of cytoplasmic, cortical, and surface-associated forces. However, teasing apart the contributions of these forces and how a viscoelastic cell responds has long been a key question in developmental biology. Recent advances in applying biophysical approaches to these questions is leading to a fundamentally new understanding of morphogenesis. In this review, we discuss how computational analysis of experimental findings and in silico modeling of Drosophila gastrulation processes has led to a deeper comprehension of the physical principles at work in the early embryo. We also summarize many of the emerging methodologies that permit biophysical analysis as well as those that provide direct and indirect measurements of force directions and magnitudes. Finally, we examine the multiple frameworks that have been used to model tissue and cellular behaviors.
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Affiliation(s)
- Dinah Loerke
- Department of Physics and Astronomy, University of Denver, Denver, CO 80208, USA.
| | - J Todd Blankenship
- Department of Biological Sciences, University of Denver, Denver, CO 80208, USA.
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141
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Petridou NI, Heisenberg C. Tissue rheology in embryonic organization. EMBO J 2019; 38:e102497. [PMID: 31512749 PMCID: PMC6792012 DOI: 10.15252/embj.2019102497] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/12/2019] [Accepted: 07/17/2019] [Indexed: 12/18/2022] Open
Abstract
Tissue morphogenesis in multicellular organisms is brought about by spatiotemporal coordination of mechanical and chemical signals. Extensive work on how mechanical forces together with the well-established morphogen signalling pathways can actively shape living tissues has revealed evolutionary conserved mechanochemical features of embryonic development. More recently, attention has been drawn to the description of tissue material properties and how they can influence certain morphogenetic processes. Interestingly, besides the role of tissue material properties in determining how much tissues deform in response to force application, there is increasing theoretical and experimental evidence, suggesting that tissue material properties can abruptly and drastically change in development. These changes resemble phase transitions, pointing at the intriguing possibility that important morphogenetic processes in development, such as symmetry breaking and self-organization, might be mediated by tissue phase transitions. In this review, we summarize recent findings on the regulation and role of tissue material properties in the context of the developing embryo. We posit that abrupt changes of tissue rheological properties may have important implications in maintaining the balance between robustness and adaptability during embryonic development.
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142
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Abstract
Cell-cell junctions are specializations of the plasma membrane responsible for physically integrating cells into tissues. We are now beginning to appreciate the diverse impacts that mechanical forces exert upon the integrity and function of these junctions. Currently, this is best understood for cadherin-based adherens junctions in epithelia and endothelia, where cell-cell adhesion couples the contractile cytoskeletons of cells together to generate tissue-scale tension. Junctional tension participates in morphogenesis and tissue homeostasis. Changes in tension can also be detected by mechanotransduction pathways that allow cells to communicate with each other. In this review, we discuss progress in characterising the forces present at junctions in physiological conditions; the cellular mechanisms that generate intrinsic tension and detect changes in tension; and, finally, we consider how tissue integrity is maintained in the face of junctional stresses.
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143
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Mongera A, Michaut A, Guillot C, Xiong F, Pourquié O. Mechanics of Anteroposterior Axis Formation in Vertebrates. Annu Rev Cell Dev Biol 2019; 35:259-283. [PMID: 31412208 PMCID: PMC7394480 DOI: 10.1146/annurev-cellbio-100818-125436] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The vertebrate anteroposterior axis forms through elongation of multiple tissues during embryogenesis. This process is based on tissue-autonomous mechanisms of force generation and intertissue mechanical coupling whose failure leads to severe developmental anomalies such as body truncation and spina bifida. Similar to other morphogenetic modules, anteroposterior body extension requires both the rearrangement of existing materials-such as cells and extracellular matrix-and the local addition of new materials, i.e., anisotropic growth, through cell proliferation, cell growth, and matrix deposition. Numerous signaling pathways coordinate body axis formation via regulation of cell behavior during tissue rearrangements and/or volumetric growth. From a physical perspective, morphogenesis depends on both cell-generated forces and tissue material properties. As the spatiotemporal variation of these mechanical parameters has recently been explored in the context of vertebrate body elongation, the study of this process is likely to shed light on the cross talk between signaling and mechanics during morphogenesis.
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Affiliation(s)
- Alessandro Mongera
- Department of Genetics, Harvard Medical School, and Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA;
| | - Arthur Michaut
- Department of Genetics, Harvard Medical School, and Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA;
| | - Charlène Guillot
- Department of Genetics, Harvard Medical School, and Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA;
| | - Fengzhu Xiong
- Department of Genetics, Harvard Medical School, and Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA;
| | - Olivier Pourquié
- Department of Genetics, Harvard Medical School, and Department of Pathology, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA;
- Harvard Stem Cell Institute, Harvard University, Cambridge, Massachusetts 02138, USA
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144
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Brillouin microscopy: an emerging tool for mechanobiology. Nat Methods 2019; 16:969-977. [PMID: 31548707 DOI: 10.1038/s41592-019-0543-3] [Citation(s) in RCA: 192] [Impact Index Per Article: 38.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 07/29/2019] [Indexed: 12/14/2022]
Abstract
The role and importance of mechanical properties of cells and tissues in cellular function, development and disease has widely been acknowledged, however standard techniques currently used to assess them exhibit intrinsic limitations. Recently, Brillouin microscopy, a type of optical elastography, has emerged as a non-destructive, label- and contact-free method that can probe the viscoelastic properties of biological samples with diffraction-limited resolution in 3D. This led to increased attention amongst the biological and medical research communities, but it also sparked debates about the interpretation and relevance of the measured physical quantities. Here, we review this emerging technology by describing the underlying biophysical principles and discussing the interpretation of Brillouin spectra arising from heterogeneous biological matter. We further elaborate on the technique's limitations, as well as its potential for gaining insights in biology, in order to guide interested researchers from various fields.
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145
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Zuela-Sopilniak N, Lammerding J. Engineering approaches to studying cancer cell migration in three-dimensional environments. Philos Trans R Soc Lond B Biol Sci 2019; 374:20180219. [PMID: 31431175 PMCID: PMC6627017 DOI: 10.1098/rstb.2018.0219] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2019] [Indexed: 12/24/2022] Open
Abstract
Cancer is one of the most devastating diseases of our time, with 17 million new cancer cases and 9.5 million cancer deaths in 2018 worldwide. The mortality associated with cancer results primarily from metastasis, i.e. the spreading of cancer cells from the primary tumour to other organs. The invasion and migration of cells through basement membranes, tight interstitial spaces and endothelial cell layers are key steps in the metastatic cascade. Recent studies demonstrated that cell migration through three-dimensional environments that mimic the in vivo conditions significantly differs from their migration on two-dimensional surfaces. Here, we review recent technological advances made in the field of cancer research that provide more 'true to the source' experimental platforms and measurements for the study of cancer cell invasion and migration in three-dimensional environments. These include microfabrication, three-dimensional bioprinting and intravital imaging tools, along with force and stiffness measurements of cells and their environments. These techniques will enable new studies that better reflect the physiological environment found in vivo, thereby producing more robust results. The knowledge achieved through these studies will aid in the development of new treatment options with the potential to ultimately lighten the devastating cost cancer inflicts on patients and their families. This article is part of a discussion meeting issue 'Forces in cancer: interdisciplinary approaches in tumour mechanobiology'.
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Affiliation(s)
| | - Jan Lammerding
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
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146
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Spurlin JW, Siedlik MJ, Nerger BA, Pang MF, Jayaraman S, Zhang R, Nelson CM. Mesenchymal proteases and tissue fluidity remodel the extracellular matrix during airway epithelial branching in the embryonic avian lung. Development 2019; 146:dev.175257. [PMID: 31371376 DOI: 10.1242/dev.175257] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 07/16/2019] [Indexed: 12/31/2022]
Abstract
Reciprocal epithelial-mesenchymal signaling is essential for morphogenesis, including branching of the lung. In the mouse, mesenchymal cells differentiate into airway smooth muscle that wraps around epithelial branches, but this contractile tissue is absent from the early avian lung. Here, we have found that branching morphogenesis in the embryonic chicken lung requires extracellular matrix (ECM) remodeling driven by reciprocal interactions between the epithelium and mesenchyme. Before branching, the basement membrane wraps the airway epithelium as a spatially uniform sheath. After branch initiation, however, the basement membrane thins at branch tips; this remodeling requires mesenchymal expression of matrix metalloproteinase 2, which is necessary for branch extension but for not branch initiation. As branches extend, tenascin C (TNC) accumulates in the mesenchyme several cell diameters away from the epithelium. Despite its pattern of accumulation, TNC is expressed exclusively by epithelial cells. Branch extension coincides with deformation of adjacent mesenchymal cells, which correlates with an increase in mesenchymal fluidity at branch tips that may transport TNC away from the epithelium. These data reveal novel epithelial-mesenchymal interactions that direct ECM remodeling during airway branching morphogenesis.
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Affiliation(s)
- James W Spurlin
- Departments of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Michael J Siedlik
- Departments of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Bryan A Nerger
- Departments of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Mei-Fong Pang
- Departments of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Sahana Jayaraman
- Departments of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Rawlison Zhang
- Departments of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, USA
| | - Celeste M Nelson
- Departments of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, USA .,Molecular Biology, Princeton University, Princeton, NJ 08544, USA
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147
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Schliffka MF, Maître JL. Stay hydrated: basolateral fluids shaping tissues. Curr Opin Genet Dev 2019; 57:70-77. [DOI: 10.1016/j.gde.2019.06.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 06/15/2019] [Accepted: 06/21/2019] [Indexed: 01/29/2023]
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148
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Li N, Xie T, Sun Y. Towards organogenesis and morphogenesis in vitro: harnessing engineered microenvironment and autonomous behaviors of pluripotent stem cells. Integr Biol (Camb) 2019; 10:574-586. [PMID: 30225509 DOI: 10.1039/c8ib00116b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recently, researchers have been attempting to control pluripotent stem cell fate or generate self-organized tissues from stem cells. Advances in bioengineering enable generation of organotypic structures, which capture the cellular components, spatial cell organization and even some functions of tissues or organs in development. However, only a few engineering tools have been utilized to regulate the formation and organization of spatially complex tissues derived from stem cells. Here, we provide a review of recent progress in the culture of organotypic structures in vitro, focusing on how microengineering approaches including geometric confinement, extracellular matrix (ECM) property modulation, spatially controlled biochemical factors, and external forces, can be utilized to generate organotypic structures. Moreover, we will discuss potential technologies that can be applied to further control both soluble and insoluble factors spatiotemporally in vitro. In summary, advanced engineered approaches have a great promise in generating miniaturized tissues and organs in a reproducible fashion, facilitating the cellular and molecular understanding of embryogenesis and morphogenesis processes.
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Affiliation(s)
- Ningwei Li
- Department of Mechanical and Industrial Engineering, University of Massachusetts, Amherst, Massachusetts 01003, USA.
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149
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Jackson S, Meeks C, Vézina A, Robey RW, Tanner K, Gottesman MM. Model systems for studying the blood-brain barrier: Applications and challenges. Biomaterials 2019; 214:119217. [PMID: 31146177 DOI: 10.1016/j.biomaterials.2019.05.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 05/13/2019] [Accepted: 05/16/2019] [Indexed: 12/21/2022]
Abstract
The blood-brain barrier (BBB) poses a serious impediment to the delivery of effective therapies to the central nervous system (CNS). Over time, various model systems have been crafted and used to evaluate the complexities of the BBB, which includes an impermeable physical barrier and a series of energy-dependent efflux pumps. Models of the BBB have mainly sought to assess changes in endothelial cell permeability, the role of ATP-dependent efflux transporters in drug disposition, and alterations in communication between BBB cells and the microenvironment. In the context of disease, various animal models have been utilized to examine real time BBB drug permeability, CNS dynamic changes, and overall treatment response. In this review, we outline the use of these in vitro and in vivo blood-brain barrier model systems to study normal physiology and diseased states. These current models each have their own advantages and disadvantages for studying the response of biologic processes to physiological and pathological conditions. Additional models are needed to mimic more closely the dynamic quality of the BBB, with the goal focused on potential clinical applications.
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Affiliation(s)
- Sadhana Jackson
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States.
| | - Caitlin Meeks
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Amélie Vézina
- Neuro-Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, United States
| | - Robert W Robey
- Multidrug Resistance Section, Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
| | - Kandice Tanner
- Tissue Morphodynamics Unit, Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
| | - Michael M Gottesman
- Multidrug Resistance Section, Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, United States
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150
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D'Angelo A, Dierkes K, Carolis C, Salbreux G, Solon J. In Vivo Force Application Reveals a Fast Tissue Softening and External Friction Increase during Early Embryogenesis. Curr Biol 2019; 29:1564-1571.e6. [PMID: 31031116 PMCID: PMC6509404 DOI: 10.1016/j.cub.2019.04.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 02/06/2019] [Accepted: 04/03/2019] [Indexed: 11/23/2022]
Abstract
During development, cell-generated forces induce tissue-scale deformations to shape the organism [1,2]. The pattern and extent of these deformations depend not solely on the temporal and spatial profile of the generated force fields but also on the mechanical properties of the tissues that the forces act on. It is thus conceivable that, much like the cell-generated forces, the mechanical properties of tissues are modulated during development in order to drive morphogenesis toward specific developmental endpoints. Although many approaches have recently emerged to assess effective mechanical parameters of tissues [3-8], they could not quantitatively relate spatially localized force induction to tissue-scale deformations in vivo. Here, we present a method that overcomes this limitation. Our approach is based on the application of controlled forces on a single microparticle embedded in an individual cell of an embryo. Combining measurements of bead displacement with the analysis of induced deformation fields in a continuum mechanics framework, we quantify material properties of the tissue and follow their changes over time. In particular, we uncover a rapid change in tissue response occurring during Drosophila cellularization, resulting from a softening of the blastoderm and an increase of external friction. We find that the microtubule cytoskeleton is a major contributor to epithelial mechanics at this stage. We identify developmentally controlled modulations in perivitelline spacing that can account for the changes in friction. Overall, our method allows for the measurement of key mechanical parameters governing tissue-scale deformations and flows occurring during morphogenesis.
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Affiliation(s)
- Arturo D'Angelo
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | - Kai Dierkes
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | - Carlo Carolis
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain
| | | | - Jérôme Solon
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Dr. Aiguader 88, Barcelona 08003, Spain; Universitat Pompeu Fabra (UPF), Barcelona, Spain.
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