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Manifacier I, Beussman KM, Han SJ, Sniadecki NJ, About I, Milan JL. The consequence of substrates of large-scale rigidity on actin network tension in adherent cells. Comput Methods Biomech Biomed Engin 2019; 22:1073-1082. [PMID: 31204851 DOI: 10.1080/10255842.2019.1629428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
There is compelling evidence that substrate stiffness affects cell adhesion as well as cytoskeleton organization and contractile activity. This work was designed to study the cytoskeletal contractile activity of single cells plated on micropost substrates of different stiffness using a numerical model simulating the intracellular tension of individual cells. We allowed cells to adhere onto micropost substrates of various rigidities and used experimental traction force data to infer cell contractility using a numerical model. The model shows that higher substrate stiffness leads to an increase in intracellular tension. The strength of this model is its ability to calculate the mechanical state of each cell in accordance to its individual cytoskeletal structure. This is achieved by regenerating a numerical cytoskeleton based on microscope images of the actin network of each cell. The resulting numerical structure consequently represents pulling characteristics on its environment similar to those generated by the cell in-vivo. From actin imaging we can calculate and better understand how forces are transmitted throughout the cell.
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Affiliation(s)
- Ian Manifacier
- Aix Marseille Univ, CNRS, ISM , Marseille , France.,Aix Marseille University, APHM, CNRS, ISM, Sainte-Marguerite Hospital, Institute for Locomotion , Marseille , France
| | - Kevin M Beussman
- Department of Mechanical Engineering, University of Washington , Seattle , WA , USA.,Center for Cardiovascular Biology, University of Washington , Seattle , WA , USA.,Institute for Stem Cell and Regenerative Medicine, University of Washington , Seattle , WA , USA
| | - Sangyoon J Han
- Department of Cell Biology, Harvard Medical School , Boston , WA , USA.,Department of Cell Biology, University of Texas Southwestern Medical Center at Dallas , Dallas , TX
| | - Nathan J Sniadecki
- Department of Mechanical Engineering, University of Washington , Seattle , WA , USA.,Center for Cardiovascular Biology, University of Washington , Seattle , WA , USA.,Institute for Stem Cell and Regenerative Medicine, University of Washington , Seattle , WA , USA.,Department of Bioengineering, University of Washington , Seattle , WA, USA
| | - Imad About
- Aix Marseille Univ, CNRS, ISM , Marseille , France
| | - Jean-Louis Milan
- Aix Marseille Univ, CNRS, ISM , Marseille , France.,Aix Marseille University, APHM, CNRS, ISM, Sainte-Marguerite Hospital, Institute for Locomotion , Marseille , France
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2
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Cui X, Murakami T, Tamura Y, Aoki K, Hoshino Y, Miura Y. Bacterial Inhibition and Osteoblast Adhesion on Ti Alloy Surfaces Modified by Poly(PEGMA- r-Phosmer) Coating. ACS APPLIED MATERIALS & INTERFACES 2018; 10:23674-23681. [PMID: 29944334 DOI: 10.1021/acsami.8b07757] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We have synthesized and immobilized PEGMA500-Phosmer to Ti6Al4V surfaces by a simple procedure to reduce bacteria-associated infection without degrading the cell response. Adhered bacteria coverage was lessened to 1% on polymer-coated surfaces when exposed to Escherichia coli, Staphylococcus epidermidis, and Streptococcus mutans. Moreover, PEGMA500-Phosmer and homoPhosmer coatings presented better responses to MC3T3-E1 preosteoblast cells when compared with the results for PEGMA2000-Phosmer-coated and raw Ti alloy surfaces. The behavior of balancing bacterial inhibition and cell attraction of the PEGMA500-Phosmer coating was explained by the grafted phosphate groups, with an appropriate PEG brush length facilitating greater levels of calcium deposition and further fibronectin adsorption when compared with that of the raw Ti alloy surface.
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Affiliation(s)
- Xinnan Cui
- Department of Chemical Engineering, Graduate School of Engineering , Kyushu University , 744 Motooka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Tatsuya Murakami
- Center for Nano Materials and Technology , Japan Advanced Institute of Science and Technology , 1-1 Asahidai , Nomi , Ishikawa 923-1292 , Japan
| | | | | | - Yu Hoshino
- Department of Chemical Engineering, Graduate School of Engineering , Kyushu University , 744 Motooka , Nishi-ku, Fukuoka 819-0395 , Japan
| | - Yoshiko Miura
- Department of Chemical Engineering, Graduate School of Engineering , Kyushu University , 744 Motooka , Nishi-ku, Fukuoka 819-0395 , Japan
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3
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Liu T. Simulation of cell-substrate traction force dynamics in response to soluble factors. Biomech Model Mechanobiol 2017; 16:1255-1268. [PMID: 28224240 DOI: 10.1007/s10237-017-0886-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 02/04/2017] [Indexed: 11/29/2022]
Abstract
Finite element (FE) simulations of contractile responses of vascular muscular thin films (vMTFs) and endothelial cells resting on an array of microposts under stimulation of soluble factors were conducted in comparison with experimental measurements reported in the literature. Two types of constitutive models were employed in the simulations, i.e. smooth muscle cell type and non-smooth muscle cell type. The time histories of the effects of soluble factors were obtained via calibration against experimental measurements of contractile responses of tissues or cells. The numerical results for vMTFs with micropatterned tissues suggest that the radius of curvature of vMTFs under stimulation of soluble factors is sensitive to width of the micropatterned tissue, i.e. the radius of curvature increases as the tissue width decreases. However, as the tissue response is essentially isometric, the time history of the maximum principal stress of the micropatterned tissues is not sensitive to tissue width. Good agreement has been achieved for predictions of the vasoconstrictor endothelin-1-induced contraction stress between the FE numerical simulation and the experiment-based approach of Alford (Integr Biol 3:1063-1070, 2011) for the vMTFs with 40, 60, 80 and 100 [Formula: see text] width patterns. This may suggest the contraction stress is weakly sensitive to the tissue width for these patterns. However, for 20 [Formula: see text] width tissue patterning, the numerical simulation result for contraction stress is less than the average value of experimental measurements, which may suggest the thinner and more elongated spindle-like cells within the 20 [Formula: see text] width tissue patterning have higher contractile output. The constitutive model for non-smooth muscle cells was used to simulate the contractile response of the endothelial cells. The substrate was treated as an effective continuum. For agonists such as lysophosphatidic acid and vascular endothelial growth factor, the deformation of the cell diminishes from edge to centre and the central part of the cell is essentially under isometric state. Numerical studies demonstrated the scenarios that cell polarity can be triggered via manipulation of the effective stiffness and Possion's ratio of the substrate.
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Affiliation(s)
- Tao Liu
- Centre for Structural Engineering and Informatics, Department of Civil Engineering, Faculty of Engineering, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
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4
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Shen X, Jia Z, D'Alonzo D, Wang X, Bruder E, Emch FH, De Geyter C, Zhang H. HECTD1 controls the protein level of IQGAP1 to regulate the dynamics of adhesive structures. Cell Commun Signal 2017; 15:2. [PMID: 28073378 PMCID: PMC5225595 DOI: 10.1186/s12964-016-0156-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Accepted: 12/06/2016] [Indexed: 12/21/2022] Open
Abstract
Background Cell migration including collective cell movement and individual cell migration are crucial factors in embryogenesis. During the spreading/migration of cells, several types of adhesive structures physically interacting with the extracellular matrix (ECM) or with another cell have been described and the formation and maturation of adhesion structures are coordinated, however the molecular pathways involved are still not fully understood. Results We generated a mouse embryonic fibroblast line (MEF) from homozygous mutant (Hectd1R/R, Hectd1Gt(RRC200)) mouse of the E3 ubiquitin ligase for inhibin B receptor (Hectd1). Detailed examination of cell motion on MEF cells demonstrated that loss of Hectd1 resulted in accelerated cell spreading and migration but impaired directionality of migration. In Hectd1R/R cells paxillin and zyxin were largely mis-localized, whereas their expression levels were unchanged. In addition the formation of focal adhesions (FAs) was impaired and the focal complexes (FXs) were increased. We further identified HECTD1 as a key regulator of IQGAP1. IQGAP1 co-localized together with HECTD1 in the leading edge of cells. HECTD1 interacted with IQGAP1 and regulated its degradation through ubiquitination. Over-expression of IQGAP1 in control MEF phenocopied the spreading and migration defects of Hectd1R/R cells. In contrast, siRNA-mediated knockdown of IQGAP1 rescued the defects in cellular movement of Hectd1R/R cells. Conclusions The E3 ligase activity of Hectd1 regulates the protein level of IQGAP1 through ubiquitination and therefore mediates the dynamics of FXs including the recruitment of paxillin and actinin. IQGAP1 is one of the effectors of HECTD1. Electronic supplementary material The online version of this article (doi:10.1186/s12964-016-0156-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xiaoli Shen
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland.,Present Address: Chongqing Reproductive and Genetics Institute, 64 Jing Tang ST, Yu Zhong District, Chongqing, 400013, China
| | - Zanhui Jia
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland.,Present Address: 2nd hospital of Jilin University, Changchun, China
| | - Donato D'Alonzo
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland
| | - Xinggang Wang
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland
| | - Elisabeth Bruder
- Pathologie, Universitätsspital Basel, Schönbeinstrasse 40, CH-4031, Basel, Switzerland
| | - Fabienne Hélène Emch
- Clinic of Gynecological Endocrinology and Reproductive Medicine, University Hospital, University of Basel, Basel, Switzerland
| | - Christian De Geyter
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland.,Clinic of Gynecological Endocrinology and Reproductive Medicine, University Hospital, University of Basel, Basel, Switzerland
| | - Hong Zhang
- Department of Biomedicine, University Hospital, University of Basel, Basel, Switzerland. .,Department of Biomedicine, University of Basel, Hebelstra. 20, CH-4031, Basel, Switzerland.
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Albert PJ, Schwarz US. Modeling cell shape and dynamics on micropatterns. Cell Adh Migr 2016; 10:516-528. [PMID: 26838278 PMCID: PMC5079397 DOI: 10.1080/19336918.2016.1148864] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 01/26/2016] [Indexed: 12/29/2022] Open
Abstract
Adhesive micropatterns have become a standard tool to study cells under defined conditions. Applications range from controlling the differentiation and fate of single cells to guiding the collective migration of cell sheets. In long-term experiments, single cell normalization is challenged by cell division. For all of these setups, mathematical models predicting cell shape and dynamics can guide pattern design. Here we review recent advances in predicting and explaining cell shape, traction forces and dynamics on micropatterns. Starting with contour models as the simplest approach to explain concave cell shapes, we move on to network and continuum descriptions as examples for static models. To describe dynamic processes, cellular Potts, vertex and phase field models can be used. Different types of model are appropriate to address different biological questions and together, they provide a versatile tool box to predict cell behavior on micropatterns.
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Affiliation(s)
- Philipp J. Albert
- Institute for Theoretical Physics and BioQuant, Heidelberg University, Heidelberg, Germany
| | - Ulrich S. Schwarz
- Institute for Theoretical Physics and BioQuant, Heidelberg University, Heidelberg, Germany
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6
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Cell sensing of physical properties at the nanoscale: Mechanisms and control of cell adhesion and phenotype. Acta Biomater 2016; 30:26-48. [PMID: 26596568 DOI: 10.1016/j.actbio.2015.11.027] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2015] [Revised: 11/10/2015] [Accepted: 11/16/2015] [Indexed: 12/24/2022]
Abstract
The chemistry, geometry, topography and mechanical properties of biomaterials modulate biochemical signals (in particular ligand-receptor binding events) that control cells-matrix interactions. In turn, the regulation of cell adhesion by the biochemical and physical properties of the matrix controls cell phenotypes such as proliferation, motility and differentiation. In particular, nanoscale geometrical, topographical and mechanical properties of biomaterials are essential to achieve control of the cell-biomaterials interface. The design of such nanoscale architectures and platforms requires understanding the molecular mechanisms underlying adhesion formation and the assembly of the actin cytoskeleton. This review presents some of the important molecular mechanisms underlying cell adhesion to biomaterials mediated by integrins and discusses the nanoscale engineered platforms used to control these processes. Such nanoscale understanding of the cell-biomaterials interface offers exciting opportunities for the design of biomaterials and their application to the field of tissue engineering. STATEMENT OF SIGNIFICANCE Biomaterials design is important in the fields of regenerative medicine and tissue engineering, in particular to allow the long term expansion of stem cells and the engineering of scaffolds for tissue regeneration. Cell adhesion to biomaterials often plays a central role in regulating cell phenotype. It is emerging that physical properties of biomaterials, and more generally the microenvironment, regulate such behaviour. In particular, cells respond to nanoscale physical properties of their matrix. Understanding how such nanoscale physical properties control cell adhesion is therefore essential for biomaterials design. To this aim, a deeper understanding of molecular processes controlling cell adhesion, but also a greater control of matrix engineering is required. Such multidisciplinary approaches shed light on some of the fundamental mechanisms via which cell adhesions sense their nanoscale physical environment.
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7
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Dynamics of cell shape and forces on micropatterned substrates predicted by a cellular Potts model. Biophys J 2015; 106:2340-52. [PMID: 24896113 DOI: 10.1016/j.bpj.2014.04.036] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 04/23/2014] [Accepted: 04/25/2014] [Indexed: 11/23/2022] Open
Abstract
Micropatterned substrates are often used to standardize cell experiments and to quantitatively study the relation between cell shape and function. Moreover, they are increasingly used in combination with traction force microscopy on soft elastic substrates. To predict the dynamics and steady states of cell shape and forces without any a priori knowledge of how the cell will spread on a given micropattern, here we extend earlier formulations of the two-dimensional cellular Potts model. The third dimension is treated as an area reservoir for spreading. To account for local contour reinforcement by peripheral bundles, we augment the cellular Potts model by elements of the tension-elasticity model. We first parameterize our model and show that it accounts for momentum conservation. We then demonstrate that it is in good agreement with experimental data for shape, spreading dynamics, and traction force patterns of cells on micropatterned substrates. We finally predict shapes and forces for micropatterns that have not yet been experimentally studied.
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8
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Bruinink A, Luginbuehl R. Evaluation of biocompatibility using in vitro methods: interpretation and limitations. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2014; 126:117-52. [PMID: 21989487 DOI: 10.1007/10_2011_111] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
The in vitro biocompatibility of novel materials has to be proven before a material can be used as component of a medical device. This must be done in cell culture tests according to internationally recognized standard protocols. Subsequently, preclinical and clinical tests must be performed to verify the safety of the new material and device. The present chapter focuses on the first step, the in vitro testing according to ISO 10993-5, and critically discusses its limited significance. Alternative strategies and a brief overview of activities to improve the current in vitro tests are presented in the concluding section.
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Affiliation(s)
- Arie Bruinink
- Laboratory for Materials - Biology Interactions, Empa - Materials Science and Technology, Lerchenfeldstasse 5, CH-9014 St, Gallen, Switzerland,
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9
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WU PEIJUNG, LIN CHOUCHINGK, JU MINGSHAUNG. AXIAL-SYMMETRIC MODELING AND KINEMATIC ANALYSIS OF SPREADING OF SPARSELY CULTURED FIBROBLASTS. J MECH MED BIOL 2013. [DOI: 10.1142/s0219519413500620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Cell spreading plays an important role in the modulation of physiological functions such as inflammation and cancer metastasis. The Brownian ratchet model and Bell's model have been used to simulate actin dynamics and bond kinetics for focal adhesion dynamics, respectively. In the present study, these models were modified and two additional subcellular mechanisms, integrin and myosin kinetics, were incoporated. An integrin recruitment function was introduced to determine the size of a focal adhesion associated with the substrate stiffness. The relationship between myosin concentration and the actin protrusion velocity was described by a first-order differential equation. Subcellular processes, including cell protrusion, focal adhesion formation, and stress fiber formation, were integrated into an axial-symmetric biophysical model, while inputs to the model were kinematic data from time-lapse experiments. Numerical simulations of the model using the Gillespie algorithm showed that dynamics of cell spreading can be well described by the model.
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Affiliation(s)
- PEI-JUNG WU
- Department of Mechanical Engineering, National Cheng Kung University, Tainan 701, Taiwan
| | - CHOU-CHING K. LIN
- Medical Device Innovation Center, National Cheng Kung University, Tainan 701, Taiwan
- Department of Neurology, College of Medicine, National Cheng Kung University Hospital, Tainan 701, Taiwan
| | - MING-SHAUNG JU
- Department of Mechanical Engineering, National Cheng Kung University, Tainan 701, Taiwan
- Medical Device Innovation Center, National Cheng Kung University, Tainan 701, Taiwan
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10
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Loosli Y, Labouesse C, Luginbuehl R, Meister JJ, Snedeker JG, Vianay B. An actin length threshold regulates adhesion maturation at the lamellipodium/lamellum interface. Integr Biol (Camb) 2013; 5:865-76. [DOI: 10.1039/c3ib20282h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Y. Loosli
- Department of Orthopedics, University of Zurich, Balgrist University Hospital, Zurich, Switzerland
- Institute for Biomechanics, ETH Zurich, Switzerland
- RMS foundation, Bettlach, Switzerland
| | - C. Labouesse
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne - SB - IPSB - LCB, Station 19, 1015 Lausanne, Switzerland. Fax: +41 21 693 83 05; Tel: +41 21 693 83 37
| | | | - J.-J. Meister
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne - SB - IPSB - LCB, Station 19, 1015 Lausanne, Switzerland. Fax: +41 21 693 83 05; Tel: +41 21 693 83 37
| | - J. G. Snedeker
- Department of Orthopedics, University of Zurich, Balgrist University Hospital, Zurich, Switzerland
- Institute for Biomechanics, ETH Zurich, Switzerland
| | - B. Vianay
- Laboratory of Cell Biophysics, Ecole Polytechnique Fédérale de Lausanne - SB - IPSB - LCB, Station 19, 1015 Lausanne, Switzerland. Fax: +41 21 693 83 05; Tel: +41 21 693 83 37
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11
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Loosli Y, Vianay B, Luginbuehl R, Snedeker JG. Numerically bridging lamellipodial and filopodial activity during cell spreading reveals a potentially novel trigger of focal adhesion maturation. Integr Biol (Camb) 2012; 4:508-21. [PMID: 22453759 DOI: 10.1039/c2ib00158f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We present a novel approach to modeling cell spreading, and use it to reveal a potentially central mechanism regulating focal adhesion maturation in various cell phenotypes. Actin bundles that span neighboring focal complexes at the lamellipodium-lamellum interface were assumed to be loaded by intracellular forces in proportion to bundle length. We hypothesized that the length of an actin bundle (with the corresponding accumulated force at its adhesions) may thus regulate adhesion maturation to ensure cell mechanical stability and morphological integrity. We developed a model to test this hypothesis, implementing a "top-down" approach to simplify certain cellular processes while explicitly incorporating complexity of other key subcellular mechanisms. Filopodial and lamellipodial activities were treated as modular processes with functional spatiotemporal interactions coordinated by rules regarding focal adhesion turnover and actin bundle dynamics. This theoretical framework was able to robustly predict temporal evolution of cell area and cytoskeletal organization as reported from a wide range of cell spreading experiments using micropatterned substrates. We conclude that a geometric/temporal modeling framework can capture the key functional aspects of the rapid spreading phase and resultant cytoskeletal complexity. Hence the model is used to reveal mechanistic insight into basic cell behavior essential for spreading. It demonstrates that actin bundles spanning nascent focal adhesions such that they are aligned to the leading edge may accumulate centripetal endogenous forces along their length, and could thus trigger focal adhesion maturation in a force-length dependent fashion. We suggest that this mechanism could be a central "integrating" factor that effectively coordinates force-mediated adhesion maturation at the lamellipodium-lamellum interface.
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Affiliation(s)
- Y Loosli
- Orthopedic Research Laboratory, University of Zurich, Forchstrasse 340, Balgrist, CH-8008 Zurich, Switzerland
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12
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Deguchi S, Matsui TS, Iio K. The position and size of individual focal adhesions are determined by intracellular stress-dependent positive regulation. Cytoskeleton (Hoboken) 2011; 68:639-51. [DOI: 10.1002/cm.20541] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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13
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Murrell M, Pontani LL, Guevorkian K, Cuvelier D, Nassoy P, Sykes C. Spreading dynamics of biomimetic actin cortices. Biophys J 2011; 100:1400-9. [PMID: 21402021 DOI: 10.1016/j.bpj.2011.01.038] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Revised: 12/31/2010] [Accepted: 01/07/2011] [Indexed: 10/18/2022] Open
Abstract
Reconstituted systems mimicking cells are interesting tools for understanding the details of cell behavior. Here, we use an experimental system that mimics cellular actin cortices, namely liposomes developing an actin shell close to their inner membrane, and we study their dynamics of spreading. We show that depending on the morphology of the actin shell inside the liposome, spreading dynamics is either reminiscent of a bare liposome (in the case of a sparse actin shell) or of a cell (in the case of a continuous actin shell). We use a mechanical model that qualitatively accounts for the shape of the experimental curves. From the data on spreading dynamics, we extract characteristic times that are consistent with mechanical estimates. The mechanical characterization of such stripped-down experimental systems paves the way for a more complex design closer to a cell. We report here the first step in building an artificial cell and studying its mechanics.
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Affiliation(s)
- Michael Murrell
- Institut Curie, Centre de Recherche, Centre National de la Recherche Scientifique, UMR168, Université Paris 6, Paris, France
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Bohner M, Loosli Y, Baroud G, Lacroix D. Commentary: Deciphering the link between architecture and biological response of a bone graft substitute. Acta Biomater 2011; 7:478-84. [PMID: 20709195 DOI: 10.1016/j.actbio.2010.08.008] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2010] [Revised: 07/07/2010] [Accepted: 08/10/2010] [Indexed: 01/12/2023]
Abstract
Hundreds of studies have been devoted to the search for the ideal architecture for bone scaffold. Despite these efforts, results are often contradictory, and rules derived from these studies are accordingly vague. In fact, there is enough evidence to postulate that ideal scaffold architecture does not exist. The aim of this document is to explain this statement and review new approaches to decipher the existing but complex link between scaffold architecture and in vivo response.
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Viceconti M, Kohl P. The virtual physiological human: computer simulation for integrative biomedicine I. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2010; 368:2591-2594. [PMID: 20439263 DOI: 10.1098/rsta.2010.0096] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Affiliation(s)
- Marco Viceconti
- Laboratorio di Tecnologia Medica, Istituto Ortopedico Rizzoli, Bologna, Italy.
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