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Jin L, Si K, Li Z, He H, Wu L, Ma B, Ren X, Huang B. Multiple collapses of blastocysts after full blastocyst formation is an independent risk factor for aneuploidy - a study based on AI and manual validation. Reprod Biol Endocrinol 2024; 22:81. [PMID: 39010092 DOI: 10.1186/s12958-024-01242-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 06/04/2024] [Indexed: 07/17/2024] Open
Abstract
BACKGROUND The occurrence of blastocyst collapse may become an indicator of preimplantation embryo quality assessment. It has been reported that collapsing blastocysts can lead to higher rates of aneuploidy and poorer clinical outcomes, but more large-scale studies are needed to explore this relationship. This study explored the characteristics of blastocyst collapse identified and quantified by artificial intelligence and explored the associations between blastocyst collapse and embryo ploidy, morphological quality, and clinical outcomes. METHODS This observational study included data from 3288 biopsied blastocysts in 1071 time-lapse preimplantation genetic testing cycles performed between January 2019 and February 2023 at a single academic fertility center. All transferred blastocysts are euploid blastocysts. The artificial intelligence recognized blastocyst collapse in time-lapse microscopy videos and then registered the collapsing times, and the start time, the recovery duration, the shrinkage percentage of each collapse. The effects of blastocyst collapse and embryo ploidy, pregnancy, live birth, miscarriage, and embryo quality were studied using available data from 1196 euploid embryos and 1300 aneuploid embryos. RESULTS 5.6% of blastocysts collapsed at least once only before the full blastocyst formation (tB), 19.4% collapsed at least once only after tB, and 3.1% collapsed both before and after tB. Multiple collapses of blastocysts after tB (times ≥ 2) are associated with higher aneuploid rates (54.6%, P > 0.05; 70.5%, P < 0.001; 72.5%, P = 0.004; and 71.4%, P = 0.049 in blastocysts collapsed 1, 2, 3 or ≥ 4 times), which remained significant after adjustment for confounders (OR = 2.597, 95% CI 1.464-4.607, P = 0.001). Analysis of the aneuploid embryos showed a higher ratio of collapses and multiple collapses after tB in monosomies and embryos with subchromosomal deletion of segmental nature (P < 0.001). Blastocyst collapse was associated with delayed embryonic development and declined blastocyst quality. There is no significant difference in pregnancy and live birth rates between collapsing and non-collapsing blastocysts. CONCLUSIONS Blastocyst collapse is common during blastocyst development. This study underlined that multiple blastocyst collapses after tB may be an independent risk factor for aneuploidy which should be taken into account by clinicians and embryologists when selecting blastocysts for transfer.
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Affiliation(s)
- Lei Jin
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical Colleine, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Keyi Si
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical Colleine, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Zhou Li
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical Colleine, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Hui He
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical Colleine, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Li Wu
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical Colleine, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Bingxin Ma
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical Colleine, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Xinling Ren
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical Colleine, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Bo Huang
- Reproductive Medicine Center, Tongji Hospital, Tongji Medical Colleine, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China.
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2
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Qiu Y, Gao T, Smith BR. Mechanical deformation and death of circulating tumor cells in the bloodstream. Cancer Metastasis Rev 2024:10.1007/s10555-024-10198-3. [PMID: 38980581 DOI: 10.1007/s10555-024-10198-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 06/28/2024] [Indexed: 07/10/2024]
Abstract
The circulation of tumor cells through the bloodstream is a significant step in tumor metastasis. To better understand the metastatic process, circulating tumor cell (CTC) survival in the circulation must be explored. While immune interactions with CTCs in recent decades have been examined, research has yet to sufficiently explain some CTC behaviors in blood flow. Studies related to CTC mechanical responses in the bloodstream have recently been conducted to further study conditions under which CTCs might die. While experimental methods can assess the mechanical properties and death of CTCs, increasingly sophisticated computational models are being built to simulate the blood flow and CTC mechanical deformation under fluid shear stresses (FSS) in the bloodstream.Several factors contribute to the mechanical deformation and death of CTCs as they circulate. While FSS can damage CTC structure, diverse interactions between CTCs and blood components may either promote or hinder the next metastatic step-extravasation at a remote site. Overall understanding of how these factors influence the deformation and death of CTCs could serve as a basis for future experiments and simulations, enabling researchers to predict CTC death more accurately. Ultimately, these efforts can lead to improved metastasis-specific therapeutics and diagnostics specific in the future.
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Affiliation(s)
- Yunxiu Qiu
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, 48824, USA
- The Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, MI, 48824, USA
| | - Tong Gao
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI, 48824, USA
- Department of Computational Mathematics, Science, and Engineering, East Lansing, MI, 48824, USA
| | - Bryan Ronain Smith
- Department of Chemical Engineering and Materials Science, Michigan State University, East Lansing, MI, 48824, USA.
- The Institute for Quantitative Health Science & Engineering, Michigan State University, East Lansing, MI, 48824, USA.
- Department of Mechanical Engineering, Michigan State University, East Lansing, MI, 48824, USA.
- Department of Biomedical Engineering, Michigan State University, East Lansing, MI, 48824, USA.
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3
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Thekkethil N, Köry J, Guo M, Stewart PS, Hill NA, Luo X. Modelling the rheology of living cell cytoplasm: poroviscoelasticity and fluid-to-solid transition. Biomech Model Mechanobiol 2024:10.1007/s10237-024-01854-2. [PMID: 38976113 DOI: 10.1007/s10237-024-01854-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 04/17/2024] [Indexed: 07/09/2024]
Abstract
Eukaryotic cell rheology has important consequences for vital processes such as adhesion, migration, and differentiation. Experiments indicate that cell cytoplasm can exhibit both elastic and viscous characteristics in different regimes, while the transport of fluid (cytosol) through the cross-linked filamentous scaffold (cytoskeleton) is reminiscent of mass transfer by diffusion through a porous medium. To gain insights into this complex rheological behaviour, we construct a computational model for the cell cytoplasm as a poroviscoelastic material formulated on the principles of nonlinear continuum mechanics, where we model the cytoplasm as a porous viscoelastic scaffold with an embedded viscous fluid flowing between the pores to model the cytosol. Baseline simulations (neglecting the viscosity of the cytosol) indicate that the system exhibits seven different regimes across the parameter space spanned by the viscoelastic relaxation timescale of the cytoskeleton and the poroelastic diffusion timescale; these regimes agree qualitatively with experimental measurements. Furthermore, the theoretical model also allows us to elucidate the additional role of pore fluid viscosity, which enters the system as a distinct viscous timescale. We show that increasing this viscous timescale hinders the passage of the pore fluid (reducing the poroelastic diffusion) and makes the cytoplasm rheology increasingly incompressible, shifting the phase boundaries between the regimes.
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Affiliation(s)
- Namshad Thekkethil
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK.
| | - Jakub Köry
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
| | - Ming Guo
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, USA
| | - Peter S Stewart
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
| | - Nicholas A Hill
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
| | - Xiaoyu Luo
- School of Mathematics and Statistics, University of Glasgow, Glasgow, UK
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4
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Dow LP, Parmar T, Marchetti MC, Pruitt BL. Engineering tools for quantifying and manipulating forces in epithelia. BIOPHYSICS REVIEWS 2023; 4:021303. [PMID: 38510344 PMCID: PMC10903508 DOI: 10.1063/5.0142537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2023] [Accepted: 04/20/2023] [Indexed: 03/22/2024]
Abstract
The integrity of epithelia is maintained within dynamic mechanical environments during tissue development and homeostasis. Understanding how epithelial cells mechanosignal and respond collectively or individually is critical to providing insight into developmental and (patho)physiological processes. Yet, inferring or mimicking mechanical forces and downstream mechanical signaling as they occur in epithelia presents unique challenges. A variety of in vitro approaches have been used to dissect the role of mechanics in regulating epithelia organization. Here, we review approaches and results from research into how epithelial cells communicate through mechanical cues to maintain tissue organization and integrity. We summarize the unique advantages and disadvantages of various reduced-order model systems to guide researchers in choosing appropriate experimental systems. These model systems include 3D, 2D, and 1D micromanipulation methods, single cell studies, and noninvasive force inference and measurement techniques. We also highlight a number of in silico biophysical models that are informed by in vitro and in vivo observations. Together, a combination of theoretical and experimental models will aid future experiment designs and provide predictive insight into mechanically driven behaviors of epithelial dynamics.
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Affiliation(s)
| | - Toshi Parmar
- Department of Physics, University of California Santa Barbara, Santa Barbara, California 93106, USA
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5
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Splitt RL, DeMali KA. Metabolic reprogramming in response to cell mechanics. Biol Cell 2023; 115:e202200108. [PMID: 36807920 PMCID: PMC10192020 DOI: 10.1111/boc.202200108] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 02/20/2023]
Abstract
Much attention has been dedicated to understanding how cells sense and respond to mechanical forces. The types of forces cells experience as well as the repertoire of cell surface receptors that sense these forces have been identified. Key mechanisms for transmitting that force to the cell interior have also emerged. Yet, how cells process mechanical information and integrate it with other cellular events remains largely unexplored. Here we review the mechanisms underlying mechanotransduction at cell-cell and cell-matrix adhesions, and we summarize the current understanding of how cells integrate information from the distinct adhesion complexes with cell metabolism.
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Affiliation(s)
- Rebecca L. Splitt
- Department of Biochemistry and Molecular Biology, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242
| | - Kris A. DeMali
- Department of Biochemistry and Molecular Biology, University of Iowa Roy J. and Lucille A. Carver College of Medicine, Iowa City, IA 52242
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Lolo FN, Pavón DM, Grande-García A, Elosegui-Artola A, Segatori VI, Sánchez S, Trepat X, Roca-Cusachs P, del Pozo MA. Caveolae couple mechanical stress to integrin recycling and activation. eLife 2022; 11:e82348. [PMID: 36264062 PMCID: PMC9747151 DOI: 10.7554/elife.82348] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 10/19/2022] [Indexed: 12/15/2022] Open
Abstract
Cells are subjected to multiple mechanical inputs throughout their lives. Their ability to detect these environmental cues is called mechanosensing, a process in which integrins play an important role. During cellular mechanosensing, plasma membrane (PM) tension is adjusted to mechanical stress through the buffering action of caveolae; however, little is known about the role of caveolae in early integrin mechanosensing regulation. Here, we show that Cav1KO fibroblasts increase adhesion to FN-coated beads when pulled with magnetic tweezers, as compared to wild type fibroblasts. This phenotype is Rho-independent and mainly derived from increased active β1-integrin content on the surface of Cav1KO fibroblasts. Florescence recovery after photobleaching analysis and endocytosis/recycling assays revealed that active β1-integrin is mostly endocytosed through the clathrin independent carrier/glycosylphosphatidyl inositol (GPI)-enriched endocytic compartment pathway and is more rapidly recycled to the PM in Cav1KO fibroblasts, in a Rab4 and PM tension-dependent manner. Moreover, the threshold for PM tension-driven β1-integrin activation is lower in Cav1KO mouse embryonic fibroblasts (MEFs) than in wild type MEFs, through a mechanism dependent on talin activity. Our findings suggest that caveolae couple mechanical stress to integrin cycling and activation, thereby regulating the early steps of the cellular mechanosensing response.
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Affiliation(s)
- Fidel-Nicolás Lolo
- Mechanoadaptation and Caveolae Biology Laboratory, Cell and developmental Biology Area, Centro Nacional de Investigaciones CardiovascularesMadridSpain
| | - Dácil María Pavón
- Mechanoadaptation and Caveolae Biology Laboratory, Cell and developmental Biology Area, Centro Nacional de Investigaciones CardiovascularesMadridSpain
| | - Araceli Grande-García
- Mechanoadaptation and Caveolae Biology Laboratory, Cell and developmental Biology Area, Centro Nacional de Investigaciones CardiovascularesMadridSpain
| | | | - Valeria Inés Segatori
- Mechanoadaptation and Caveolae Biology Laboratory, Cell and developmental Biology Area, Centro Nacional de Investigaciones CardiovascularesMadridSpain
| | - Sara Sánchez
- Mechanoadaptation and Caveolae Biology Laboratory, Cell and developmental Biology Area, Centro Nacional de Investigaciones CardiovascularesMadridSpain
| | - Xavier Trepat
- Institute for Bioengineering of CataloniaBarcelonaSpain
| | | | - Miguel A del Pozo
- Mechanoadaptation and Caveolae Biology Laboratory, Cell and developmental Biology Area, Centro Nacional de Investigaciones CardiovascularesMadridSpain
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7
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Xu D, Zhang N, Wang S, Zhang P, Li Y, Yang H. A method for generating dynamic compression shear coupled stress loading on living cells. Front Bioeng Biotechnol 2022; 10:1002661. [PMID: 36213067 PMCID: PMC9532543 DOI: 10.3389/fbioe.2022.1002661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 08/24/2022] [Indexed: 11/15/2022] Open
Abstract
Changes in the mechanical properties of single cells are related to the physiological state and fate of cells. The construction of cell constitutive equations is essential for understanding the material characteristics of single cells. With the help of atomic force microscopy, bio-image processing algorithms, and other technologies, research investigating the mechanical properties of cells during static/quasi-static processes has developed rapidly. A series of equivalent models, such as viscoelastic models, have been proposed to describe the constitutive behaviors of cells. The stress-strain relations under dynamic processes are essential to completing the constitutive equations of living cells. To explore the dynamic mechanical properties of cells, we propose a novel method to generate a controllable dynamical compression shear coupling stress on living cells. A CFD model was established to visualize this method and display the theories, as well as assess the scope of the application. As the requirements or limitations are met, researchers can adjust the details of this model according to their lab environment or experimental demands. This micro-flow channel-based method is a new tool for approaching the dynamic mechanical properties of cells.
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Affiliation(s)
- Dasen Xu
- School of Aeronautics, Northwestern Polytechnical University, Xi’an, China
- Center of Special Environmental Biomechanics; Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
| | - Nu Zhang
- Center of Special Environmental Biomechanics; Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Life Science, Northwestern Polytechnical University, Xi’an, China
| | - Sijie Wang
- Center of Special Environmental Biomechanics; Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Life Science, Northwestern Polytechnical University, Xi’an, China
| | - Pan Zhang
- Center of Special Environmental Biomechanics; Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Life Science, Northwestern Polytechnical University, Xi’an, China
| | - Yulong Li
- Center of Special Environmental Biomechanics; Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Civil Aviation, Northwestern Polytechnical University, Xi’an, China
- Joint International Research Laboratory of Impact Dynamic and Its Engineering Application, Xi’an, China
- *Correspondence: Yulong Li, ; Hui Yang,
| | - Hui Yang
- Center of Special Environmental Biomechanics; Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Life Science, Northwestern Polytechnical University, Xi’an, China
- *Correspondence: Yulong Li, ; Hui Yang,
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8
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Marhuenda E, Villarino A, Narciso M, Elowsson L, Almendros I, Westergren-Thorsson G, Farré R, Gavara N, Otero J. Development of a physiomimetic model of acute respiratory distress syndrome by using ECM hydrogels and organ-on-a-chip devices. Front Pharmacol 2022; 13:945134. [PMID: 36188621 PMCID: PMC9517737 DOI: 10.3389/fphar.2022.945134] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/08/2022] [Indexed: 11/13/2022] Open
Abstract
Acute Respiratory Distress Syndrome is one of the more common fatal complications in COVID-19, characterized by a highly aberrant inflammatory response. Pre-clinical models to study the effect of cell therapy and anti-inflammatory treatments have not comprehensively reproduced the disease due to its high complexity. This work presents a novel physiomimetic in vitro model for Acute Respiratory Distress Syndrome using lung extracellular matrix-derived hydrogels and organ-on-a-chip devices. Monolayres of primary alveolar epithelial cells were cultured on top of decellullarized lung hydrogels containing primary lung mesenchymal stromal cells. Then, cyclic stretch was applied to mimic breathing, and an inflammatory response was induced by using a bacteriotoxin hit. Having simulated the inflamed breathing lung environment, we assessed the effect of an anti-inflammatory drug (i.e., dexamethasone) by studying the secretion of the most relevant inflammatory cytokines. To better identify key players in our model, the impact of the individual factors (cyclic stretch, decellularized lung hydrogel scaffold, and the presence of mesenchymal stromal cells) was studied separately. Results showed that developed model presented a more reduced inflammatory response than traditional models, which is in line with what is expected from the response commonly observed in patients. Further, from the individual analysis of the different stimuli, it was observed that the use of extracellular matrix hydrogels obtained from decellularized lungs had the most significant impact on the change of the inflammatory response. The developed model then opens the door for further in vitro studies with a better-adjusted response to the inflammatory hit and more robust results in the test of different drugs or cell therapy.
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Affiliation(s)
- Esther Marhuenda
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, University de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
| | - Alvaro Villarino
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, University de Barcelona, Barcelona, Spain
| | - Maria Narciso
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, University de Barcelona, Barcelona, Spain
- The Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Linda Elowsson
- Lung Biology, Biomedical Center, Department of Medical Science,Lund University, Lund, Sweden
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, University de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | | | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, University de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, Barcelona, Spain
| | - Núria Gavara
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, University de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
- The Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Jorge Otero
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, University de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
- The Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain
- *Correspondence: Jorge Otero,
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Xu D, Zhang N, Wang S, Yu Y, Zhang P, Li Y, Yang H. A Novel In Vitro Platform Development in the Lab for Modeling Blast Injury to Microglia. Front Bioeng Biotechnol 2022; 10:883545. [PMID: 35903797 PMCID: PMC9315251 DOI: 10.3389/fbioe.2022.883545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 06/10/2022] [Indexed: 11/23/2022] Open
Abstract
Traumatic brain injury (TBI), which is mainly caused by impact, often results in chronic neurological abnormalities. Since the pathological changes in vivo during primary biomechanical injury are quite complicated, the in-depth understanding of the pathophysiology and mechanism of TBI depends on the establishment of an effective experimental in vitro model. Usually, a bomb explosive blast was employed to establish the in vitro model, while the process is complex and unsuitable in the lab. Based on water-hammer, we have developed a device system to provide a single dynamic compression stress on living cells. A series of amplitude (∼5.3, ∼9.8, ∼13.5 MPa) were generated to explore the effects of dynamic compression loading on primary microglia within 48 h. Apoptosis experiments indicated that primary microglia had strong tolerance to blast waves. In addition, the generation of intercellular reactive oxygen species and secretory nitric oxide was getting strongly enhanced and recovered within 48 h. In addition, there is a notable release of pro-inflammatory cytokine by microglia. Our work provides a reproducible and peaceable method of loading single dynamic compression forces to cells in vitro. Microglia showed an acute inflammatory response to dynamic loadings, while no significant cell death was observed. This insight delivers a new technological approach that could open new areas to a better understanding of the mechanism of cell blast injuries.
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Affiliation(s)
- Dasen Xu
- School of Aeronautics, Northwestern Polytechnical University, Xi’an, China
- Center of Special Environmental Biomechanics and Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
| | - Nu Zhang
- Center of Special Environmental Biomechanics and Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Life Sciences, Northwestern Polytechnical University, Xi’an, China
| | - Sijie Wang
- Center of Special Environmental Biomechanics and Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Life Sciences, Northwestern Polytechnical University, Xi’an, China
| | - Yawei Yu
- School of Life Sciences, Northwestern Polytechnical University, Xi’an, China
| | - Pan Zhang
- Center of Special Environmental Biomechanics and Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Life Sciences, Northwestern Polytechnical University, Xi’an, China
| | - Yulong Li
- School of Aeronautics, Northwestern Polytechnical University, Xi’an, China
- Center of Special Environmental Biomechanics and Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- *Correspondence: Yulong Li, ; Hui Yang,
| | - Hui Yang
- Center of Special Environmental Biomechanics and Biomedical Engineering, Northwestern Polytechnical University, Xi’an, China
- School of Life Sciences, Northwestern Polytechnical University, Xi’an, China
- *Correspondence: Yulong Li, ; Hui Yang,
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Abstract
Embryonic cells grow in environments that provide a plethora of physical cues, including mechanical forces that shape the development of the entire embryo. Despite their prevalence, the role of these forces in embryonic development and their integration with chemical signals have been mostly neglected, and scrutiny in modern molecular embryology tilted, instead, towards the dissection of molecular pathways involved in cell fate determination and patterning. It is now possible to investigate how mechanical signals induce downstream genetic regulatory networks to regulate key developmental processes in the embryo. Here, we review the insights into mechanical control of early vertebrate development, including the role of forces in tissue patterning and embryonic axis formation. We also highlight recent in vitro approaches using individual embryonic stem cells and self-organizing multicellular models of human embryos, which have been instrumental in expanding our understanding of how mechanics tune cell fate and cellular rearrangements during human embryonic development.
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11
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Rothermel TM, Cook BL, Alford PW. Cellular Microbiaxial Stretching Assay for Measurement and Characterization of the Anisotropic Mechanical Properties of Micropatterned Cells. Curr Protoc 2022; 2:e370. [PMID: 35195953 DOI: 10.1002/cpz1.370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Characterizing the mechanical properties of single cells is important for developing descriptive models of tissue mechanics and improving the understanding of mechanically driven cell processes. Standard methods for measuring single-cell mechanical properties typically provide isotropic mechanical descriptions. However, many cells exhibit specialized geometries in vivo, with anisotropic cytoskeletal architectures reflective of their function, and are exposed to dynamic multiaxial loads, raising the need for more complete descriptions of their anisotropic mechanical properties under complex deformations. Here, we describe the cellular microbiaxial stretching (CμBS) assay in which controlled deformations are applied to micropatterned cells while simultaneously measuring cell stress. CμBS utilizes a set of linear actuators to apply tensile or compressive, short- or long-term deformations to cells micropatterned on a fluorescent bead-doped polyacrylamide gel. Using traction force microscopy principles and the known geometry of the cell and the mechanical properties of the underlying gel, we calculate the stress within the cell to formulate stress-strain curves that can be further used to create mechanical descriptions of the cells, such as strain energy density functions. © 2022 Wiley Periodicals LLC. Basic Protocol 1: Assembly of CμBS stretching constructs Basic Protocol 2: Polymerization of micropatterned, bead-doped polyacrylamide gel on an elastomer membrane Support Protocol: Cell culture and seeding onto CμBS constructs Basic Protocol 3: Implementing CμBS stretching protocols and traction force microscopy Basic Protocol 4: Data analysis and cell stress measurements.
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Affiliation(s)
- Taylor M Rothermel
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota
| | - Bernard L Cook
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota
| | - Patrick W Alford
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, Minnesota
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12
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Júnior C, Narciso M, Marhuenda E, Almendros I, Farré R, Navajas D, Otero J, Gavara N. Baseline Stiffness Modulates the Non-Linear Response to Stretch of the Extracellular Matrix in Pulmonary Fibrosis. Int J Mol Sci 2021; 22:12928. [PMID: 34884731 PMCID: PMC8657558 DOI: 10.3390/ijms222312928] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 11/23/2021] [Accepted: 11/25/2021] [Indexed: 12/15/2022] Open
Abstract
Pulmonary fibrosis (PF) is a progressive disease that disrupts the mechanical homeostasis of the lung extracellular matrix (ECM). These effects are particularly relevant in the lung context, given the dynamic nature of cyclic stretch that the ECM is continuously subjected to during breathing. This work uses an in vivo model of pulmonary fibrosis to characterize the macro- and micromechanical properties of lung ECM subjected to stretch. To that aim, we have compared the micromechanical properties of fibrotic ECM in baseline and under stretch conditions, using a novel combination of Atomic Force Microscopy (AFM) and a stretchable membrane-based chip. At the macroscale, fibrotic ECM displayed strain-hardening, with a stiffness one order of magnitude higher than its healthy counterpart. Conversely, at the microscale, we found a switch in the stretch-induced mechanical behaviour of the lung ECM from strain-hardening at physiological ECM stiffnesses to strain-softening at fibrotic ECM stiffnesses. Similarly, we observed solidification of healthy ECM versus fluidization of fibrotic ECM in response to stretch. Our results suggest that the mechanical behaviour of fibrotic ECM under stretch involves a potential built-in mechanotransduction mechanism that may slow down the progression of PF by steering resident fibroblasts away from a pro-fibrotic profile.
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Affiliation(s)
- Constança Júnior
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (C.J.); (M.N.); (E.M.); (I.A.); (R.F.); (D.N.); (J.O.)
- The Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Maria Narciso
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (C.J.); (M.N.); (E.M.); (I.A.); (R.F.); (D.N.); (J.O.)
- The Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
| | - Esther Marhuenda
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (C.J.); (M.N.); (E.M.); (I.A.); (R.F.); (D.N.); (J.O.)
- CIBER de Enfermedades Respiratorias, 28029 Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, 08036 Barcelona, Spain
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (C.J.); (M.N.); (E.M.); (I.A.); (R.F.); (D.N.); (J.O.)
- CIBER de Enfermedades Respiratorias, 28029 Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, 08036 Barcelona, Spain
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (C.J.); (M.N.); (E.M.); (I.A.); (R.F.); (D.N.); (J.O.)
- CIBER de Enfermedades Respiratorias, 28029 Madrid, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer, 08036 Barcelona, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (C.J.); (M.N.); (E.M.); (I.A.); (R.F.); (D.N.); (J.O.)
- The Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
- CIBER de Enfermedades Respiratorias, 28029 Madrid, Spain
| | - Jorge Otero
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (C.J.); (M.N.); (E.M.); (I.A.); (R.F.); (D.N.); (J.O.)
- The Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
- CIBER de Enfermedades Respiratorias, 28029 Madrid, Spain
| | - Núria Gavara
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina i Ciències de la Salut, Universitat de Barcelona, 08036 Barcelona, Spain; (C.J.); (M.N.); (E.M.); (I.A.); (R.F.); (D.N.); (J.O.)
- The Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), 08028 Barcelona, Spain
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Yeh CF, Chou C, Yang KC. Mechanotransduction in fibrosis: Mechanisms and treatment targets. CURRENT TOPICS IN MEMBRANES 2021; 87:279-314. [PMID: 34696888 DOI: 10.1016/bs.ctm.2021.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
To perceive and integrate the environmental cues, cells and tissues sense and interpret various physical forces like shear, tensile, and compression stress. Mechanotransduction involves the sensing and translation of mechanical forces into biochemical and mechanical signals to guide cell fate and achieve tissue homeostasis. Disruption of this mechanical homeostasis by tissue injury elicits multiple cellular responses leading to pathological matrix deposition and tissue stiffening, and consequent evolution toward pro-inflammatory/pro-fibrotic phenotypes, leading to tissue/organ fibrosis. This review focuses on the molecular mechanisms linking mechanotransduction to fibrosis and uncovers the potential therapeutic targets to halt or resolve fibrosis.
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Affiliation(s)
- Chih-Fan Yeh
- Division of Cardiology, Department of Internal Medicine and Cardiovascular Center, National Taiwan University Hospital, Taipei, Taiwan; Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Caroline Chou
- Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan; Washington University in St. Louis, St. Louis, MO, United States
| | - Kai-Chien Yang
- Division of Cardiology, Department of Internal Medicine and Cardiovascular Center, National Taiwan University Hospital, Taipei, Taiwan; Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan; Research Center for Developmental Biology & Regenerative Medicine, National Taiwan University, Taipei, Taiwan; Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan.
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14
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De Moudt S, Leloup A, Fransen P. Aortic Stiffness Hysteresis in Isolated Mouse Aortic Segments Is Intensified by Contractile Stimuli, Attenuated by Age, and Reversed by Elastin Degradation. Front Physiol 2021; 12:723972. [PMID: 34650441 PMCID: PMC8507434 DOI: 10.3389/fphys.2021.723972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 08/23/2021] [Indexed: 11/13/2022] Open
Abstract
Aim: Cyclic stretch of vascular tissue at any given pressure reveals greater dimensions during unloading than during loading, which determines the cardiac beat-by-beat hysteresis loop on the pressure-diameter/volume relationship. The present study did not focus on hysteresis during a single stretch cycle but investigated whether aortic stiffness determined during continuous stretch at different pressures also displayed hysteresis phenomena. Methods: Aortic segments from C57Bl6 mice were mounted in the Rodent Oscillatory Set-up for Arterial Compliance (ROTSAC), where they were subjected to high frequency (10 Hz) cyclic stretch at alternating loads equivalent to a constant theoretical pulse pressure of 40 mm Hg. Diastolic and systolic diameter, compliance, and the Peterson elastic modulus (Ep), as a measure of aortic stiffness, was determined starting at cyclic stretch between alternating loads corresponding to 40 and 80 mm Hg, at each gradual load increase equivalent to 20 mm Hg, up to loads equivalent to pressures of 220 and 260 mm Hg (loading direction) and then repeated in the downward direction (unloading direction). This was performed in baseline conditions and following contraction by α1 adrenergic stimulation with phenylephrine or by depolarization with high extracellular K+ in aortas of young (5 months), aged (26 months) mice, and in segments treated with elastase. Results: In baseline conditions, diastolic/systolic diameters and compliance for a pulse pressure of 40 mm Hg were larger at any given pressure upon unloading (decreasing pressure) than loading (increasing pressure) of the aortic segments. The pressure-aortic stiffness (Ep) relationship was similar in the loading and unloading directions, and aortic hysteresis was absent. On the other hand, hysteresis was evident after activation of the VSMCs with the α1 adrenergic agonist phenylephrine and with depolarization by high extracellular K+, especially after inhibition of basal NO release with L-NAME. Aortic stiffness was significantly smaller in the unloading than in the loading direction. In comparison with young mice, old-mouse aortic segments also displayed contraction-dependent aortic hysteresis, but hysteresis was shifted to a lower pressure range. Elastase-treated segments showed higher stiffness upon unloading over nearly the whole pressure range. Conclusions: Mouse aortic segments display pressure- and contraction-dependent diameter, compliance, and stiffness hysteresis phenomena, which are modulated by age and VSMC-extracellular matrix interactions. This may have implications for aortic biomechanics in pathophysiological conditions and aging.
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Affiliation(s)
- Sofie De Moudt
- Physiopharmacology, Department Pharmaceutical Sciences, University of Antwerp, Antwerpen, Belgium
| | - Arthur Leloup
- Physiopharmacology, Department Pharmaceutical Sciences, University of Antwerp, Antwerpen, Belgium
| | - Paul Fransen
- Physiopharmacology, Department Pharmaceutical Sciences, University of Antwerp, Antwerpen, Belgium
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15
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Artzy-Schnirman A, Arber Raviv S, Doppelt Flikshtain O, Shklover J, Korin N, Gross A, Mizrahi B, Schroeder A, Sznitman J. Advanced human-relevant in vitro pulmonary platforms for respiratory therapeutics. Adv Drug Deliv Rev 2021; 176:113901. [PMID: 34331989 PMCID: PMC7611797 DOI: 10.1016/j.addr.2021.113901] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Revised: 07/20/2021] [Accepted: 07/24/2021] [Indexed: 02/08/2023]
Abstract
Over the past years, advanced in vitro pulmonary platforms have witnessed exciting developments that are pushing beyond traditional preclinical cell culture methods. Here, we discuss ongoing efforts in bridging the gap between in vivo and in vitro interfaces and identify some of the bioengineering challenges that lie ahead in delivering new generations of human-relevant in vitro pulmonary platforms. Notably, in vitro strategies using foremost lung-on-chips and biocompatible "soft" membranes have focused on platforms that emphasize phenotypical endpoints recapitulating key physiological and cellular functions. We review some of the most recent in vitro studies underlining seminal therapeutic screens and translational applications and open our discussion to promising avenues of pulmonary therapeutic exploration focusing on liposomes. Undeniably, there still remains a recognized trade-off between the physiological and biological complexity of these in vitro lung models and their ability to deliver assays with throughput capabilities. The upcoming years are thus anticipated to see further developments in broadening the applicability of such in vitro systems and accelerating therapeutic exploration for drug discovery and translational medicine in treating respiratory disorders.
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Affiliation(s)
- Arbel Artzy-Schnirman
- Department of Biomedical, Technion - Israel Institute of Technology, 32000 Haifa, Israel
| | - Sivan Arber Raviv
- Department of Chemical, Technion - Israel Institute of Technology, 32000 Haifa, Israel
| | | | - Jeny Shklover
- Department of Chemical, Technion - Israel Institute of Technology, 32000 Haifa, Israel
| | - Netanel Korin
- Department of Biomedical, Technion - Israel Institute of Technology, 32000 Haifa, Israel
| | - Adi Gross
- Department of Biotechnology and Food Engineering, Technion - Israel Institute of Technology, 32000 Haifa, Israel
| | - Boaz Mizrahi
- Department of Biotechnology and Food Engineering, Technion - Israel Institute of Technology, 32000 Haifa, Israel
| | - Avi Schroeder
- Department of Chemical, Technion - Israel Institute of Technology, 32000 Haifa, Israel
| | - Josué Sznitman
- Department of Biomedical, Technion - Israel Institute of Technology, 32000 Haifa, Israel.
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16
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Nossa R, Costa J, Cacopardo L, Ahluwalia A. Breathing in vitro: Designs and applications of engineered lung models. J Tissue Eng 2021; 12:20417314211008696. [PMID: 33996022 PMCID: PMC8107677 DOI: 10.1177/20417314211008696] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 03/22/2021] [Indexed: 12/11/2022] Open
Abstract
The aim of this review is to provide a systematic design guideline to users, particularly engineers interested in developing and deploying lung models, and biologists seeking to identify a suitable platform for conducting in vitro experiments involving pulmonary cells or tissues. We first discuss the state of the art on lung in vitro models, describing the most simplistic and traditional ones. Then, we analyze in further detail the more complex dynamic engineered systems that either provide mechanical cues, or allow for more predictive exposure studies, or in some cases even both. This is followed by a dedicated section on microchips of the lung. Lastly, we present a critical discussion of the different characteristics of each type of system and the criteria which may help researchers select the most appropriate technology according to their specific requirements. Readers are encouraged to refer to the tables accompanying the different sections where comprehensive and quantitative information on the operating parameters and performance of the different systems reported in the literature is provided.
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17
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Rheinlaender J, Wirbel H, Schäffer TE. Spatial correlation of cell stiffness and traction forces in cancer cells measured with combined SICM and TFM. RSC Adv 2021; 11:13951-13956. [PMID: 35423943 PMCID: PMC8697701 DOI: 10.1039/d1ra01277k] [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: 02/16/2021] [Accepted: 04/06/2021] [Indexed: 12/31/2022] Open
Abstract
The mechanical properties of cancer cells at the single-cell and the subcellular level might be the key for answering long-standing questions in the diagnosis and treatment of cancer. However, the subcellular distribution of two main mechanical properties, cell stiffness and traction forces, has been investigated only rarely and qualitatively yet. Here, we present the first direct combination of scanning ion conductance microscopy (SICM) and traction force microscopy (TFM), which we used to identify a correlation between the local stiffness and the local traction force density in living cells. We found a correlation in normal breast epithelial cells, but no correlation in cancerous breast epithelial cells. This indicates that the interplay between cell stiffness and traction forces is altered in cancer cells as compared to healthy cells, which might give new insight in the research field of cancer cell mechanobiology.
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Affiliation(s)
- Johannes Rheinlaender
- Institute of Applied Physics, University of Tübingen Auf der Morgenstelle 10 72076 Tübingen Germany +49 7071 29 5093 +49 7071 29 76030
| | - Hannes Wirbel
- Institute of Applied Physics, University of Tübingen Auf der Morgenstelle 10 72076 Tübingen Germany +49 7071 29 5093 +49 7071 29 76030
| | - Tilman E Schäffer
- Institute of Applied Physics, University of Tübingen Auf der Morgenstelle 10 72076 Tübingen Germany +49 7071 29 5093 +49 7071 29 76030
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18
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Ficarella E, Minooei M, Santoro L, Toma E, Trentadue B, De Spirito M, Papi M, Pruncu CI, Lamberti L. Visco-Hyperelastic Characterization of the Equine Immature Zona Pellucida. MATERIALS 2021; 14:ma14051223. [PMID: 33807624 PMCID: PMC7961360 DOI: 10.3390/ma14051223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/26/2021] [Accepted: 03/01/2021] [Indexed: 12/13/2022]
Abstract
This article presents a very detailed study on the mechanical characterization of a highly nonlinear material, the immature equine zona pellucida (ZP) membrane. The ZP is modeled as a visco-hyperelastic soft matter. The Arruda–Boyce constitutive equation and the two-term Prony series are identified as the most suitable models for describing the hyperelastic and viscous components, respectively, of the ZP’s mechanical response. Material properties are identified via inverse analysis based on nonlinear optimization which fits nanoindentation curves recorded at different rates. The suitability of the proposed approach is fully demonstrated by the very good agreement between AFM data and numerically reconstructed force–indentation curves. A critical comparison of mechanical behavior of two immature ZP membranes (i.e., equine and porcine ZPs) is also carried out considering the information on the structure of these materials available from electron microscopy investigations documented in the literature.
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Affiliation(s)
- Elisa Ficarella
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70125 Bari, Italy; (E.F.); (M.M.); (L.S.); (E.T.); (B.T.)
| | - Mohammad Minooei
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70125 Bari, Italy; (E.F.); (M.M.); (L.S.); (E.T.); (B.T.)
| | - Lorenzo Santoro
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70125 Bari, Italy; (E.F.); (M.M.); (L.S.); (E.T.); (B.T.)
| | - Elisabetta Toma
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70125 Bari, Italy; (E.F.); (M.M.); (L.S.); (E.T.); (B.T.)
| | - Bartolomeo Trentadue
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70125 Bari, Italy; (E.F.); (M.M.); (L.S.); (E.T.); (B.T.)
| | - Marco De Spirito
- Istituto di Fisica, Università Cattolica del S. Cuore, 00168 Roma, Italy; (M.D.S.); (M.P.)
| | - Massimiliano Papi
- Istituto di Fisica, Università Cattolica del S. Cuore, 00168 Roma, Italy; (M.D.S.); (M.P.)
| | - Catalin I. Pruncu
- Department of Mechanical Engineering, Imperial College London, Exhibition Rd., London SW7 2AZ, UK
- Department of Design, Manufacturing & Engineering Management, University of Strathclyde, Glasgow G1 1XJ, UK
- Correspondence: or (C.I.P.); (L.L.)
| | - Luciano Lamberti
- Dipartimento di Meccanica, Matematica e Management, Politecnico di Bari, 70125 Bari, Italy; (E.F.); (M.M.); (L.S.); (E.T.); (B.T.)
- Correspondence: or (C.I.P.); (L.L.)
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19
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Radiom M, He Y, Peng-Wang J, Baeza-Squiban A, Berret JF, Chen Y. Alveolar mimics with periodic strain and its effect on the cell layer formation. Biotechnol Bioeng 2020; 117:2827-2841. [PMID: 32542664 DOI: 10.1002/bit.27458] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 04/09/2020] [Accepted: 06/13/2020] [Indexed: 12/16/2022]
Abstract
We report on the development of a new model of alveolar air-tissue interface on a chip. The model consists of an array of suspended hexagonal monolayers of gelatin nanofibers supported by microframes and a microfluidic device for the patch integration. The suspended monolayers are deformed to a central displacement of 40-80 µm at the air-liquid interface by application of air pressure in the range of 200-1,000 Pa. With respect to the diameter of the monolayers, that is, 500 µm, this displacement corresponds to a linear strain of 2-10% in agreement with the physiological strain range in the lung alveoli. The culture of A549 cells on the monolayers for an incubation time of 1-3 days showed viability in the model. We exerted a periodic strain of 5% at a frequency of 0.2 Hz for 1 hr to the cells. We found that the cells were strongly coupled to the nanofibers, but the strain reduced the coupling and induced remodeling of the actin cytoskeleton, which led to a better tissue formation. Our model can serve as a versatile tool in lung investigations such as in inhalation toxicology and therapy.
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Affiliation(s)
- Milad Radiom
- Laboratoire Matière et Systèmes Complexes, CNRS UMR 7057, Université Paris Diderot Paris-VII, Paris, France
| | - Yong He
- Département de Chimie, Sorbonne Universités-UPMC Univ Paris 06, CNRS UMR 8640, Pasteur, École Normale Supérieure-PSL Research University, Paris, France
| | - Juan Peng-Wang
- Département de Chimie, Sorbonne Universités-UPMC Univ Paris 06, CNRS UMR 8640, Pasteur, École Normale Supérieure-PSL Research University, Paris, France
| | - Armelle Baeza-Squiban
- Unité de Biologie Fonctionnelle et Adaptative, CNRS UMR 8251, Université Paris Diderot Paris-VII, Paris, France
| | - Jean-François Berret
- Laboratoire Matière et Systèmes Complexes, CNRS UMR 7057, Université Paris Diderot Paris-VII, Paris, France
| | - Yong Chen
- Département de Chimie, Sorbonne Universités-UPMC Univ Paris 06, CNRS UMR 8640, Pasteur, École Normale Supérieure-PSL Research University, Paris, France
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20
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Structural and mechanical remodeling of the cytoskeleton maintains tensional homeostasis in 3D microtissues under acute dynamic stretch. Sci Rep 2020; 10:7696. [PMID: 32376876 PMCID: PMC7203149 DOI: 10.1038/s41598-020-64725-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Accepted: 04/21/2020] [Indexed: 01/04/2023] Open
Abstract
When stretched, cells cultured on 2D substrates share a universal softening and fluidization response that arises from poorly understood remodeling of well-conserved cytoskeletal elements. It is known, however, that the structure and distribution of the cytoskeleton is profoundly influenced by the dimensionality of a cell’s environment. Therefore, in this study we aimed to determine whether cells cultured in a 3D matrix share this softening behavior and to link it to cytoskeletal remodeling. To achieve this, we developed a high-throughput approach to measure the dynamic mechanical properties of cells and allow for sub-cellular imaging within physiologically relevant 3D microtissues. We found that fibroblast, smooth muscle and skeletal muscle microtissues strain softened but did not fluidize, and upon loading cessation, they regained their initial mechanical properties. Furthermore, microtissue prestress decreased with the strain amplitude to maintain a constant mean tension. This adaptation under an auxotonic condition resulted in lengthening. A filamentous actin cytoskeleton was required, and responses were mirrored by changes to actin remodeling rates and visual evidence of stretch-induced actin depolymerization. Our new approach for assessing cell mechanics has linked behaviors seen in 2D cultures to a 3D matrix, and connected remodeling of the cytoskeleton to homeostatic mechanical regulation of tissues.
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21
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Monemian Esfahani A, Rosenbohm J, Reddy K, Jin X, Bouzid T, Riehl B, Kim E, Lim JY, Yang R. Tissue Regeneration from Mechanical Stretching of Cell-Cell Adhesion. Tissue Eng Part C Methods 2019; 25:631-640. [PMID: 31407627 PMCID: PMC6859692 DOI: 10.1089/ten.tec.2019.0098] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 08/05/2019] [Indexed: 01/09/2023] Open
Abstract
Cell-cell adhesion complexes are macromolecular adhesive organelles that integrate cells into tissues. This mechanochemical coupling in cell-cell adhesion is required for a large number of cell behaviors, and perturbations of the cell-cell adhesion structure or related mechanotransduction pathways can lead to critical pathological conditions such as skin and heart diseases, arthritis, and cancer. Mechanical stretching has been a widely used method to stimulate the mechanotransduction process originating from the cell-cell adhesion and cell-extracellular matrix (ECM) complexes. These studies aimed to reveal the biophysical processes governing cell proliferation, wound healing, gene expression regulation, and cell differentiation in various tissues, including cardiac, muscle, vascular, and bone. This review explores techniques in mechanical stretching in two-dimensional settings with different stretching regimens on different cell types. The mechanotransduction responses from these different cell types will be discussed with an emphasis on their biophysical transformations during mechanical stretching and the cross talk between the cell-cell and cell-ECM adhesion complexes. Therapeutic aspects of mechanical stretching are reviewed considering these cellular responses after the application of mechanical forces, with a focus on wound healing and tissue regeneration. Impact Statement Mechanical stretching has been proposed as a therapeutic option for tissue regeneration and wound healing. It has been accepted that mechanotransduction processes elicited by mechanical stretching govern cellular response and behavior, and these studies have predominantly focused on the cell-extracellular matrix (ECM) sites. This review serves the mechanobiology community by shifting the focus of mechanical stretching effects from cell-ECM adhesions to the less examined cell-cell adhesions, which we believe play an equally important role in orchestrating the response pathways.
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Affiliation(s)
- Amir Monemian Esfahani
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Jordan Rosenbohm
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Keerthana Reddy
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Xiaowei Jin
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Tasneem Bouzid
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Brandon Riehl
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Eunju Kim
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
| | - Jung Yul Lim
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
- Mary and Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska
| | - Ruiguo Yang
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, Nebraska
- Mary and Dick Holland Regenerative Medicine Program, University of Nebraska Medical Center, Omaha, Nebraska
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, Nebraska
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22
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Cell cluster migration: Connecting experiments with physical models. Semin Cell Dev Biol 2019; 93:77-86. [DOI: 10.1016/j.semcdb.2018.09.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 07/31/2018] [Accepted: 09/21/2018] [Indexed: 12/19/2022]
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Oliveira VR, Uriarte JJ, Falcones B, Jorba I, Zin WA, Farré R, Navajas D, Almendros I. Biomechanical Response of Lung Epithelial Cells to Iron Oxide and Titanium Dioxide Nanoparticles. Front Physiol 2019; 10:1047. [PMID: 31474879 PMCID: PMC6707084 DOI: 10.3389/fphys.2019.01047] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 07/30/2019] [Indexed: 11/30/2022] Open
Abstract
Increasing evidence shows that lungs can be damaged by inhalation of nanoparticles (NPs) at environmental and occupational settings. Recent findings have associated the exposure to iron oxide (Fe2O3) and titanium dioxide (TiO2) – NPs widely used in biomedical and clinical research – with pulmonary oxidative stress and inflammation. Although changes on cellular mechanics could contribute to pulmonary inflammation, there is no information regarding the effects of Fe2O3 and TiO2 on alveolar epithelial cell biomechanics. The aim was to investigate the NPs-induced biomechanical effects in terms of cell stiffness and traction forces exerted by human alveolar epithelial cells. Cell Young’s modulus (E) measured by atomic force microscopy in alveolar epithelial cells significantly decreased after exposure to Fe2O3 and TiO2 (∼28 and ∼25%, respectively) compared to control conditions. Moreover, both NPs induced a similar reduction in the traction forces exerted by the alveolar epithelial cells in comparison to the control conditions. Accordingly, immunofluorescence images revealed a reduction of actomyosin stress fibers in response to the exposure to NPs. However, no inflammatory response was detected. In conclusion, an acute exposure of epithelial pulmonary cells to Fe2O3 and TiO2 NPs, which was mild since it was non-cytotoxic and did not induce inflammation, modified cell biomechanical properties which could be translated into damage of the epithelial barrier integrity, suggesting that mild environmental inhalation of Fe2O3 and TiO2 NPs could not be innocuous.
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Affiliation(s)
- Vinícius Rosa Oliveira
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,Laboratório de Fisiologia da Respiração, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Juan José Uriarte
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
| | - Bryan Falcones
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
| | - Ignasi Jorba
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Walter Araujo Zin
- Laboratório de Fisiologia da Respiração, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red Enfermedades Respiratorias (CIBERES), Madrid, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,Institute for Bioengineering of Catalonia, The Barcelona Institute of Science and Technology, Barcelona, Spain.,Centro de Investigación Biomédica en Red Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Isaac Almendros
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain.,Centro de Investigación Biomédica en Red Enfermedades Respiratorias (CIBERES), Madrid, Spain.,Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
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24
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Jorba I, Beltrán G, Falcones B, Suki B, Farré R, García-Aznar JM, Navajas D. Nonlinear elasticity of the lung extracellular microenvironment is regulated by macroscale tissue strain. Acta Biomater 2019; 92:265-276. [PMID: 31085362 DOI: 10.1016/j.actbio.2019.05.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 01/02/2023]
Abstract
The extracellular matrix (ECM) of the lung provides physical support and key mechanical signals to pulmonary cells. Although lung ECM is continuously subjected to different stretch levels, detailed mechanics of the ECM at the scale of the cell is poorly understood. Here, we developed a new polydimethylsiloxane (PDMS) chip to probe nonlinear mechanics of tissue samples with atomic force microscopy (AFM). Using this chip, we performed AFM measurements in decellularized rat lung slices at controlled stretch levels. The AFM revealed highly nonlinear ECM elasticity with the microscale stiffness increasing with tissue strain. To correlate micro- and macroscale ECM mechanics, we also assessed macromechanics of decellularized rat lung strips under uniaxial tensile testing. The lung strips exhibited exponential macromechanical behavior but with stiffness values one order of magnitude lower than at the microscale. To interpret the relationship between micro- and macromechanical properties, we carried out a finite element (FE) analysis which revealed that the stiffness of the alveolar cell microenvironment is regulated by the global strain of the lung scaffold. The FE modeling also indicates that the scale dependence of stiffness is mainly due to the porous architecture of the lung parenchyma. We conclude that changes in tissue strain during breathing result in marked changes in the ECM stiffness sensed by alveolar cells providing tissue-specific mechanical signals to the cells. STATEMENT OF SIGNIFICANCE: The micromechanical properties of the extracellular matrix (ECM) are a major determinant of cell behavior. The ECM is exposed to mechanical stretching in the lung and other organs during physiological function. Therefore, a thorough knowledge of the nonlinear micromechanical properties of the ECM at the length scale that cells probe is required to advance our understanding of cell-matrix interplay. We designed a novel PDMS chip to perform atomic force microscopy measurements of ECM micromechanics on decellularized rat lung slices at different macroscopic strain levels. For the first time, our results reveal that the microscale stiffness of lung ECM markedly increases with macroscopic tissue strain. Therefore, changes in tissue strain during breathing result in variations in ECM stiffness providing tissue-specific mechanical signals to lung cells.
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25
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Li H, Mattson JM, Zhang Y. Integrating structural heterogeneity, fiber orientation, and recruitment in multiscale ECM mechanics. J Mech Behav Biomed Mater 2019; 92:1-10. [PMID: 30654215 PMCID: PMC6387859 DOI: 10.1016/j.jmbbm.2018.12.023] [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] [Received: 07/20/2018] [Revised: 11/26/2018] [Accepted: 12/18/2018] [Indexed: 01/06/2023]
Abstract
Extracellular matrix (ECM) plays critical roles in establishing tissue structure-function relationships and controlling cell fate. However, the mechanisms by which ECM mechanics influence cell and tissue behavior remain to be elucidated since the events associated with this process span length scales from the tissue to molecular level. Entirely new methods are needed in order to better understand the multiscale mechanics of ECM. In this study, a multiscale experimental approach was established by integrating Optical Magnetic Twisting Cytometry (OMTC) with a biaxial tensile tester to study the microscopic (local) ECM mechanical properties under controlled tissue-level (global) loading. Adventitial layer of porcine thoracic artery was used as a collagen-based ECM. Multiphoton microscopy imaging was performed to capture the changes in ECM fiber structure during biaxial deformation. As visualized from multiphoton microscopy images, biaxial stretch induces gradual fiber straightening and the fiber families become evident at higher stretch levels. The OMTC measurements show that the local apparent storage and loss modulus increases with the global biaxial stretch, however there exists a complex interplay among local ECM mechanical properties, ECM structural heterogeneity, and fiber distribution and engagement. The phase lag does not change significantly with global biaxial stretch. Our results also show a much faster increase in global tissue tangent modulus compared to the local apparent complex modulus with biaxial stretch, indicating the scale dependency of ECM mechanics.
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Affiliation(s)
- Haiyue Li
- Department of Mechanical Engineering, Boston University, Boston, MA 02215, USA
| | - Jeffrey M Mattson
- Department of Mechanical Engineering, Boston University, Boston, MA 02215, USA
| | - Yanhang Zhang
- Department of Mechanical Engineering, Boston University, Boston, MA 02215, USA; Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
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26
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Rosowski KA, Boltyanskiy R, Xiang Y, Van den Dries K, Schwartz MA, Dufresne ER. Vinculin and the mechanical response of adherent fibroblasts to matrix deformation. Sci Rep 2018; 8:17967. [PMID: 30568231 PMCID: PMC6299284 DOI: 10.1038/s41598-018-36272-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 11/14/2018] [Indexed: 12/21/2022] Open
Abstract
Cells respond to the mechanics of their environment. Mechanical cues include extracellular matrix (ECM) stiffness and deformation, which are primarily sensed through integrin-mediated adhesions. We investigated the impact of ECM deformation on cellular forces, measuring the time-evolution of traction forces of isolated mouse fibroblasts in response to stretch and release. Stretch triggered a marked increase of traction stresses and apparent stiffness. Expression of the focal adhesion protein vinculin not only increased baseline traction forces, but also increased dissipation of mechanical energy, which was correlated with the cells’ failure to recover baseline traction forces after release of stretch.
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Affiliation(s)
- Kathryn A Rosowski
- Department of Materials, ETH Zürich, 8093, Zürich, Switzerland.,Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT, 06511, USA
| | - Rostislav Boltyanskiy
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT, 06511, USA
| | - Yingjie Xiang
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT, 06511, USA
| | - Koen Van den Dries
- Cardiovascular Research Center and Department of Medicine (Cardiology), Yale University School of Medicine, New Haven, CT, 06511, USA.,Department of Cell Biology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Martin A Schwartz
- Cardiovascular Research Center and Department of Medicine (Cardiology), Yale University School of Medicine, New Haven, CT, 06511, USA.,Departments of Cell Biology and Biomedical Engineering, Yale University, New Haven, CT, 06511, USA
| | - Eric R Dufresne
- Department of Materials, ETH Zürich, 8093, Zürich, Switzerland. .,Department of Mechanical Engineering and Materials Science, Yale University, New Haven, CT, 06511, USA.
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27
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Win Z, Buksa JM, Alford PW. Architecture-Dependent Anisotropic Hysteresis in Smooth Muscle Cells. Biophys J 2018; 115:2044-2054. [PMID: 30348447 PMCID: PMC6303237 DOI: 10.1016/j.bpj.2018.09.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 08/24/2018] [Accepted: 09/28/2018] [Indexed: 01/03/2023] Open
Abstract
Cells within mechanically dynamic tissues like arteries are exposed to ever-changing forces and deformations. In some pathologies, like aneurysms, complex loads may alter how cells transduce forces, driving maladaptive growth and remodeling. Here, we aimed to determine the dynamic mechanical properties of vascular smooth muscle cells (VSMCs) under biaxial load. Using cellular micro-biaxial stretching microscopy, we measured the large-strain anisotropic stress-strain hysteresis of VSMCs and found that hysteresis is strongly dependent on load orientation and actin organization. Most notably, under some cyclic loads, we found that VSMCs with elongated in-vivo-like architectures display a hysteresis loop that is reverse to what is traditionally measured in polymers, with unloading stresses greater than loading stresses. This reverse hysteresis could not be replicated using a quasilinear viscoelasticity model, but we developed a Hill-type active fiber model that can describe the experimentally observed hysteresis. These results suggest that cells in highly organized tissues, like arteries, can have strongly anisotropic responses to complex loads, which could have important implications in understanding pathological mechanotransduction.
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Affiliation(s)
- Zaw Win
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, Minneapolis, Minnesota
| | - Justin M Buksa
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, Minneapolis, Minnesota
| | - Patrick W Alford
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, Minneapolis, Minnesota.
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28
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Yang R, Broussard JA, Green KJ, Espinosa HD. Techniques to stimulate and interrogate cell-cell adhesion mechanics. EXTREME MECHANICS LETTERS 2018; 20:125-139. [PMID: 30320194 PMCID: PMC6181239 DOI: 10.1016/j.eml.2017.12.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Cell-cell adhesions maintain the mechanical integrity of multicellular tissues and have recently been found to act as mechanotransducers, translating mechanical cues into biochemical signals. Mechanotransduction studies have primarily focused on focal adhesions, sites of cell-substrate attachment. These studies leverage technical advances in devices and systems interfacing with living cells through cell-extracellular matrix adhesions. As reports of aberrant signal transduction originating from mutations in cell-cell adhesion molecules are being increasingly associated with disease states, growing attention is being paid to this intercellular signaling hub. Along with this renewed focus, new requirements arise for the interrogation and stimulation of cell-cell adhesive junctions. This review covers established experimental techniques for stimulation and interrogation of cell-cell adhesion from cell pairs to monolayers.
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Affiliation(s)
- Ruiguo Yang
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588, United States
- Nebraska Center for Integrated Biomolecular Communication, University of Nebraska-Lincoln, Lincoln, NE 68588, United States
| | - Joshua A. Broussard
- Department of Pathology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, United States
- Department of Dermatology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, United States
| | - Kathleen J. Green
- Department of Pathology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, United States
- Department of Dermatology, Northwestern University, Feinberg School of Medicine, Chicago, IL 60611, United States
| | - Horacio D. Espinosa
- Department of Mechanical Engineering, Northwestern University, Evanston, IL 60208, United States
- Theoretical and Applied Mechanics Program, Northwestern University, Evanston, IL 60208, United States
- Institute for Cellular Engineering Technologies, Northwestern University, Evanston, IL 60208, United States
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29
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André Dias S, Planus E, Angely C, Lotteau L, Tissier R, Filoche M, Louis B, Pelle G, Isabey D. Perfluorocarbon induces alveolar epithelial cell response through structural and mechanical remodeling. Biomech Model Mechanobiol 2018; 17:961-973. [PMID: 29450740 DOI: 10.1007/s10237-018-1005-z] [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] [Received: 07/28/2017] [Accepted: 02/02/2018] [Indexed: 01/25/2023]
Abstract
During total liquid ventilation, lung cells are exposed to perfluorocarbon (PFC) whose chemophysical properties highly differ from standard aqueous cell feeding medium (DMEM). We herein perform a systematic study of structural and mechanical properties of A549 alveolar epithelial cells in order to characterize their response to PFC exposure, using DMEM as control condition. Changes in F-actin structure, focal adhesion density and glycocalyx distribution are evaluated by confocal fluorescent microscopy. Changes in cell mechanics and adhesion are measured by multiscale magnetic twisting cytometry (MTC). Two different microrheological models (single Voigt and power law) are used to analyze the cell mechanics characterized by cytoskeleton (CSK) stiffness and characteristic relaxation times. Cell-matrix adhesion is analyzed using a stochastic multibond deadhesion model taking into account the non-reversible character of the cell response, allowing us to quantify the adhesion weakness and the number of associated bonds. The roles of F-actin structure and glycocalyx layer are evaluated by depolymerizing F-actin and degrading glycocalyx, respectively. Results show that PFC exposure consistently induces F-actin remodeling, CSK softening and adhesion weakening. These results demonstrate that PFC triggers an alveolar epithelial cell response herein evidenced by a decay in intracellular CSK tension, an adhesion weakening and a glycocalyx layer redistribution. These PFC-induced cell adjustments are consistent with the hypothesis that cells respond to a decrease in adhesion energy at cell surface. This adhesion energy can be even further reduced in the presence of surfactant adsorbed at the cell surface.
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Affiliation(s)
- Sofia André Dias
- Inserm, IMRB, U955, Équipe 13, Biomécanique & Appareil Respiratoire, Université Paris Est, UMR S955, UPEC, CNRS, ERL 7000, 8, rue du Général Sarrail, 94010, Créteil Cedex, France.,Bertin Technologies, 78180, Montigny le Bretonneux, France
| | - Emmanuelle Planus
- Centre de Recherche, Université Grenoble Alpes, Inserm U1209, CNRS 5309, Grenoble, France
| | - Christelle Angely
- Inserm, IMRB, U955, Équipe 13, Biomécanique & Appareil Respiratoire, Université Paris Est, UMR S955, UPEC, CNRS, ERL 7000, 8, rue du Général Sarrail, 94010, Créteil Cedex, France
| | - Luc Lotteau
- Bertin Technologies, 78180, Montigny le Bretonneux, France
| | - Renaud Tissier
- Inserm, IMRB, U955, Equipe 03, Université Paris Est, UMRS955, UPEC, Ecole Nationale Vétérinaire d'Alfort, 7 avenue du général de Gaulle, 94700, Maisons-Alfort, France
| | - Marcel Filoche
- Inserm, IMRB, U955, Équipe 13, Biomécanique & Appareil Respiratoire, Université Paris Est, UMR S955, UPEC, CNRS, ERL 7000, 8, rue du Général Sarrail, 94010, Créteil Cedex, France.,Physique de la Matière Condensée, Ecole Polytechnique, CNRS, 91128, Palaiseau, France
| | - Bruno Louis
- Inserm, IMRB, U955, Équipe 13, Biomécanique & Appareil Respiratoire, Université Paris Est, UMR S955, UPEC, CNRS, ERL 7000, 8, rue du Général Sarrail, 94010, Créteil Cedex, France
| | - Gabriel Pelle
- Inserm, IMRB, U955, Équipe 13, Biomécanique & Appareil Respiratoire, Université Paris Est, UMR S955, UPEC, CNRS, ERL 7000, 8, rue du Général Sarrail, 94010, Créteil Cedex, France.,APHP, Groupe Hospitalier H. Mondor A. Chenevier, Service des Explorations Fonctionnelles, 51, Avenue du Maréchal de Lattre de Tassigny, 94010, Créteil Cedex, France
| | - Daniel Isabey
- Inserm, IMRB, U955, Équipe 13, Biomécanique & Appareil Respiratoire, Université Paris Est, UMR S955, UPEC, CNRS, ERL 7000, 8, rue du Général Sarrail, 94010, Créteil Cedex, France.
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30
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Win Z, Buksa JM, Steucke KE, Gant Luxton GW, Barocas VH, Alford PW. Cellular Microbiaxial Stretching to Measure a Single-Cell Strain Energy Density Function. J Biomech Eng 2018; 139:2618751. [PMID: 28397957 DOI: 10.1115/1.4036440] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Indexed: 01/02/2023]
Abstract
The stress in a cell due to extracellular mechanical stimulus is determined by its mechanical properties, and the structural organization of many adherent cells suggests that their properties are anisotropic. This anisotropy may significantly influence the cells' mechanotransductive response to complex loads, and has important implications for development of accurate models of tissue biomechanics. Standard methods for measuring cellular mechanics report linear moduli that cannot capture large-deformation anisotropic properties, which in a continuum mechanics framework are best described by a strain energy density function (SED). In tissues, the SED is most robustly measured using biaxial testing. Here, we describe a cellular microbiaxial stretching (CμBS) method that modifies this tissue-scale approach to measure the anisotropic elastic behavior of individual vascular smooth muscle cells (VSMCs) with nativelike cytoarchitecture. Using CμBS, we reveal that VSMCs are highly anisotropic under large deformations. We then characterize a Holzapfel-Gasser-Ogden type SED for individual VSMCs and find that architecture-dependent properties of the cells can be robustly described using a formulation solely based on the organization of their actin cytoskeleton. These results suggest that cellular anisotropy should be considered when developing biomechanical models, and could play an important role in cellular mechano-adaptation.
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Affiliation(s)
- Zaw Win
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, 312 Church Street SE NHH 7-105, Minneapolis, MN 55455 e-mail:
| | - Justin M Buksa
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, 312 Church Street SE NHH 7-105, Minneapolis, MN 55455 e-mail:
| | - Kerianne E Steucke
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, 312 Church Street SE NHH 7-105, Minneapolis, MN 55455 e-mail:
| | - G W Gant Luxton
- Department of Genetics, Cell Biology, and Development, University of Minnesota-Twin Cities, 420 Washington Avenue SE MCB 4-128, Minneapolis, MN 55455 e-mail:
| | - Victor H Barocas
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, 312 Church Street SE NHH 7-105, Minneapolis, MN 55455 e-mail:
| | - Patrick W Alford
- Department of Biomedical Engineering, University of Minnesota-Twin Cities, 312 Church Street SE NHH 7-105, Minneapolis, MN 55455 e-mail:
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31
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Li H, Xu B, Zhou EH, Sunyer R, Zhang Y. Multiscale Measurements of the Mechanical Properties of Collagen Matrix. ACS Biomater Sci Eng 2017; 3:2815-2824. [DOI: 10.1021/acsbiomaterials.6b00634] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
| | | | - Enhua H. Zhou
- Ophthalmology, Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Raimon Sunyer
- Institute for Bioengineering of Catalonia, Baldiri-Reixac 15-21, 08028, Barcelona, Spain
- Centro de Investigación Biomédica en Red en Bioingeniería, Biomateriales y Nanomedicina, Av. Monforte de Lemos, 3-5, Pabellón 11, Planta 0, 28029 Madrid, Spain
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32
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Nonaka PN, Uriarte JJ, Campillo N, Oliveira VR, Navajas D, Farré R. Lung bioengineering: physical stimuli and stem/progenitor cell biology interplay towards biofabricating a functional organ. Respir Res 2016; 17:161. [PMID: 27894293 PMCID: PMC5126992 DOI: 10.1186/s12931-016-0477-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Accepted: 11/22/2016] [Indexed: 01/18/2023] Open
Abstract
A current approach to obtain bioengineered lungs as a future alternative for transplantation is based on seeding stem cells on decellularized lung scaffolds. A fundamental question to be solved in this approach is how to drive stem cell differentiation onto the different lung cell phenotypes. Whereas the use of soluble factors as agents to modulate the fate of stem cells was established from an early stage of the research with this type of cells, it took longer to recognize that the physical microenvironment locally sensed by stem cells (e.g. substrate stiffness, 3D architecture, cyclic stretch, shear stress, air-liquid interface, oxygenation gradient) also contributes to their differentiation. The potential role played by physical stimuli would be particularly relevant in lung bioengineering since cells within the organ are physiologically subjected to two main stimuli required to facilitate efficient gas exchange: air ventilation and blood perfusion across the organ. The present review focuses on describing how the cell mechanical microenvironment can modulate stem cell differentiation and how these stimuli could be incorporated into lung bioreactors for optimizing organ bioengineering.
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Affiliation(s)
- Paula N Nonaka
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Juan J Uriarte
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Noelia Campillo
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Vinicius R Oliveira
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain.,CIBER Enfermedades Respiratorias, Madrid, Spain.,Institut de Bioenginyeria de Catalunya, Barcelona, Spain
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Casanova 143, 08036, Barcelona, Spain. .,CIBER Enfermedades Respiratorias, Madrid, Spain. .,Institut d'Investigacions Biomèdiques August Pi Sunyer, Barcelona, Spain.
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33
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Seriani R, de Souza CEC, Krempel PG, Frias DP, Matsuda M, Correia AT, Ferreira MZJ, Alencar AM, Negri EM, Saldiva PHN, Mauad T, Macchione M. Human bronchial epithelial cells exposed in vitro to diesel exhaust particles exhibit alterations in cell rheology and cytotoxicity associated with decrease in antioxidant defenses and imbalance in pro- and anti-apoptotic gene expression. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:9862-9870. [PMID: 26856867 DOI: 10.1007/s11356-016-6228-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 02/01/2016] [Indexed: 06/05/2023]
Abstract
Diesel exhaust particles (DEPs) from diesel engines produce adverse alterations in cells of the airways by activating intracellular signaling pathways and apoptotic gene overexpression, and also by influencing metabolism and cytoskeleton changes. This study used human bronchial epithelium cells (BEAS-2B) in culture and evaluates their exposure to DEPs (15ug/mL for 1 and 2 h) in order to determine changes to cell rheology (viscoelasticity) and gene expression of the enzymes involved in oxidative stress, apoptosis, and cytotoxicity. BEAS-2B cells exposed to DEPs were found to have a significant loss in stiffness, membrane stability, and mitochondrial activity. The genes involved in apoptosis [B cell lymphoma 2 (BCL-2 and caspase-3)] presented inversely proportional expressions (p = 0.05, p = 0.01, respectively), low expression of the genes involved in antioxidant responses [SOD1 (superoxide dismutase 1); SOD2 (superoxide dismutase 2), and GPx (glutathione peroxidase) (p = 0.01)], along with an increase in cytochrome P450, family 1, subfamily A, polypeptide 1 (CYP1A1) (p = 0.01). These results suggest that alterations in cell rheology and cytotoxicity could be associated with oxidative stress and imbalance between pro- and anti-apoptotic genes.
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Affiliation(s)
- Robson Seriani
- Laboratory of Experimental Air Pollution (LIM05), Department of Pathology, School of Medicine, University of São Paulo, Av. Dr. Arnaldo 455, 1°andar, sala 1150, Cerqueira César, São Paulo, SP, CEP:01246-903, Brazil.
- FAM - Faculdades das Américas, Rua Augusta, 1508, 3°andar, São Paulo, SP, 01304-001, Brazil.
| | - Claudia Emanuele Carvalho de Souza
- Laboratory of Chronopharmacology, Department of Physiology, Institute of Bioscience, University of São Paulo, Rua do Matão - travessa 14, Cidade Universitária, 05508900, São Paulo, SP, Brazil
| | - Paloma Gava Krempel
- Laboratory for Investigations in Ophthalmology (LIM-33), University of São Paulo Medical School São Paulo, Dr. Arnaldo 455, 5°andar, Cerqueira César, São Paulo, SP, CEP:01246-903, Brazil
| | - Daniela Perroni Frias
- Laboratory of Experimental Air Pollution (LIM05), Department of Pathology, School of Medicine, University of São Paulo, Av. Dr. Arnaldo 455, 1°andar, sala 1150, Cerqueira César, São Paulo, SP, CEP:01246-903, Brazil
| | - Monique Matsuda
- Laboratory for Investigations in Ophthalmology (LIM-33), University of São Paulo Medical School São Paulo, Dr. Arnaldo 455, 5°andar, Cerqueira César, São Paulo, SP, CEP:01246-903, Brazil
| | - Aristides Tadeu Correia
- Heart Institute (InCor), Department of Cardiopulmonology, University of São Paulo Medical School, Av. Dr. Enéas de Carvalho Aguiar, 44, Cerqueira Cesar, 05403-000, Sao Paulo, SP, Brazil
| | - Márcia Zotti Justo Ferreira
- Laboratory of Microrheology and Molecular Physiology, Institute of Physics, University of São Paulo, Rua do Matão, Travessa R Número 187, Cidade Universitária, 05508-090, Sao Paulo, SP, Brazil
| | - Adriano Mesquita Alencar
- Laboratory of Microrheology and Molecular Physiology, Institute of Physics, University of São Paulo, Rua do Matão, Travessa R Número 187, Cidade Universitária, 05508-090, Sao Paulo, SP, Brazil
| | - Elnara Marcia Negri
- Laboratory of Experimental Air Pollution (LIM05), Department of Pathology, School of Medicine, University of São Paulo, Av. Dr. Arnaldo 455, 1°andar, sala 1150, Cerqueira César, São Paulo, SP, CEP:01246-903, Brazil
| | - Paulo Hilário Nascimento Saldiva
- Laboratory of Experimental Air Pollution (LIM05), Department of Pathology, School of Medicine, University of São Paulo, Av. Dr. Arnaldo 455, 1°andar, sala 1150, Cerqueira César, São Paulo, SP, CEP:01246-903, Brazil
| | - Thais Mauad
- Laboratory of Experimental Air Pollution (LIM05), Department of Pathology, School of Medicine, University of São Paulo, Av. Dr. Arnaldo 455, 1°andar, sala 1150, Cerqueira César, São Paulo, SP, CEP:01246-903, Brazil
| | - Mariangela Macchione
- Laboratory of Experimental Air Pollution (LIM05), Department of Pathology, School of Medicine, University of São Paulo, Av. Dr. Arnaldo 455, 1°andar, sala 1150, Cerqueira César, São Paulo, SP, CEP:01246-903, Brazil
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Isabey D, Pelle G, André Dias S, Bottier M, Nguyen NM, Filoche M, Louis B. Multiscale evaluation of cellular adhesion alteration and cytoskeleton remodeling by magnetic bead twisting. Biomech Model Mechanobiol 2015; 15:947-63. [PMID: 26459324 DOI: 10.1007/s10237-015-0734-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 09/29/2015] [Indexed: 12/19/2022]
Abstract
Cellular adhesion forces depend on local biological conditions meaning that adhesion characterization must be performed while preserving cellular integrity. We presently postulate that magnetic bead twisting provides an appropriate stress, i.e., basically a clamp, for assessment in living cells of both cellular adhesion and mechanical properties of the cytoskeleton. A global dissociation rate obeying a Bell-type model was used to determine the natural dissociation rate ([Formula: see text]) and a reference stress ([Formula: see text]). These adhesion parameters were determined in parallel to the mechanical properties for a variety of biological conditions in which either adhesion or cytoskeleton was selectively weakened or strengthened by changing successively ligand concentration, actin polymerization level (by treating with cytochalasin D), level of exerted stress (by increasing magnetic torque), and cell environment (by using rigid and soft 3D matrices). On the whole, this multiscale evaluation of the cellular and molecular responses to a controlled stress reveals an evolution which is consistent with stochastic multiple bond theories and with literature results obtained with other molecular techniques. Present results confirm the validity of the proposed bead-twisting approach for its capability to probe cellular and molecular responses in a variety of biological conditions.
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Affiliation(s)
- Daniel Isabey
- Inserm, U955, Équipe 13, Biomécanique and Appareil Respiratoire: une approche multi-échelle, UMR S955, CNRS, ERL 7240, Université Paris Est, UPEC, 8, rue du Général Sarrail, 94010, Créteil Cedex, France.
| | - Gabriel Pelle
- Inserm, U955, Équipe 13, Biomécanique and Appareil Respiratoire: une approche multi-échelle, UMR S955, CNRS, ERL 7240, Université Paris Est, UPEC, 8, rue du Général Sarrail, 94010, Créteil Cedex, France.,APHP, Groupe Hospitalier H. Mondor A. Chenevier, Service des Explorations Fonctionnelles, 51, Avenue du Maréchal de Lattre de Tassigny, 94010, Créteil Cedex, France
| | - Sofia André Dias
- Inserm, U955, Équipe 13, Biomécanique and Appareil Respiratoire: une approche multi-échelle, UMR S955, CNRS, ERL 7240, Université Paris Est, UPEC, 8, rue du Général Sarrail, 94010, Créteil Cedex, France
| | - Mathieu Bottier
- Inserm, U955, Équipe 13, Biomécanique and Appareil Respiratoire: une approche multi-échelle, UMR S955, CNRS, ERL 7240, Université Paris Est, UPEC, 8, rue du Général Sarrail, 94010, Créteil Cedex, France
| | - Ngoc-Minh Nguyen
- Inserm, U955, Équipe 13, Biomécanique and Appareil Respiratoire: une approche multi-échelle, UMR S955, CNRS, ERL 7240, Université Paris Est, UPEC, 8, rue du Général Sarrail, 94010, Créteil Cedex, France
| | - Marcel Filoche
- Inserm, U955, Équipe 13, Biomécanique and Appareil Respiratoire: une approche multi-échelle, UMR S955, CNRS, ERL 7240, Université Paris Est, UPEC, 8, rue du Général Sarrail, 94010, Créteil Cedex, France.,Physique de la Matière Condensée, Ecole Polytechnique, CNRS, 91128, Palaiseau, France
| | - Bruno Louis
- Inserm, U955, Équipe 13, Biomécanique and Appareil Respiratoire: une approche multi-échelle, UMR S955, CNRS, ERL 7240, Université Paris Est, UPEC, 8, rue du Général Sarrail, 94010, Créteil Cedex, France
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Poon C, Boughton P, Ruys AJ. A dynamic perfusion bioreactor approach for engineering respiratory tissues in-vitro. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2013:6224-7. [PMID: 24111162 DOI: 10.1109/embc.2013.6610975] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In vitro culture of respiratory tissues poses many challenges due to the intrinsic complexity of the respiratory system. Multiple cellular phenotypes comprise the respiratory epithelium and operate under dynamic, gas-interchanging conditions that should be replicated for near-physiologic cultivation of functional tissues in vitro. A novel biomimetic perfusion bioreactor system has been proposed to reconstitute key functional conditions of the human lung. This portable system consists of several biologically-inspired components: (i) a 3-dimensional (3-D) elastomeric soft tissue scaffold construct, (ii) a mechanical actuator, (iii) a perfusion system and (iv) gaseous exchange capabilities. These integrated components operate synergistically to create a unique, dynamic air-liquid interface (ALI) environment that allows controlled application of physiological and pathological strain while complementing standard cell culture techniques. This system holds potential for engineering 3-D tissues to meet growing demand for a range of applications, from more ethical and efficient pharmaceutical screening to clinical graft transplants.
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Jurchenko C, Salaita KS. Lighting Up the Force: Investigating Mechanisms of Mechanotransduction Using Fluorescent Tension Probes. Mol Cell Biol 2015; 35:2570-82. [PMID: 26031334 PMCID: PMC4524122 DOI: 10.1128/mcb.00195-15] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The ability of cells to sense the physical nature of their surroundings is critical to the survival of multicellular organisms. Cellular response to physical cues from adjacent cells and the extracellular matrix leads to a dynamic cycle in which cells respond by remodeling their local microenvironment, fine-tuning cell stiffness, polarity, and shape. Mechanical regulation is important in cellular development, normal morphogenesis, and wound healing. The mechanisms by which these finely balanced mechanotransduction events occur, however, are not well understood. In large part, this is due to the limited availability of tools to study molecular mechanotransduction events in live cells. Several classes of molecular tension probes have been recently developed which are rapidly transforming the study of mechanotransduction. Molecular tension probes are primarily based on fluorescence resonance energy transfer (FRET) and report on piconewton scale tension events in live cells. In this minireview, we describe the two main classes of tension probes, genetically encoded tension sensors and immobilized tension sensors, and discuss the advantages and limitations of each type. We discuss future opportunities to address major biological questions and outline the challenges facing the next generation of molecular tension probes.
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Affiliation(s)
- Carol Jurchenko
- Department of Chemistry, Emory University, Atlanta, Georgia, USA
| | - Khalid S Salaita
- Department of Chemistry, Emory University, Atlanta, Georgia, USA
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37
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Gralka M, Kroy K. Inelastic mechanics: A unifying principle in biomechanics. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:3025-37. [PMID: 26151340 DOI: 10.1016/j.bbamcr.2015.06.017] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Revised: 05/13/2015] [Accepted: 06/26/2015] [Indexed: 01/16/2023]
Abstract
Many soft materials are classified as viscoelastic. They behave mechanically neither quite fluid-like nor quite solid-like - rather a bit of both. Biomaterials are often said to fall into this class. Here, we argue that this misses a crucial aspect, and that biomechanics is essentially damage mechanics, at heart. When deforming an animal cell or tissue, one can hardly avoid inducing the unfolding of protein domains, the unbinding of cytoskeletal crosslinkers, the breaking of weak sacrificial bonds, and the disruption of transient adhesions. We classify these activated structural changes as inelastic. They are often to a large degree reversible and are therefore not plastic in the proper sense, but they dissipate substantial amounts of elastic energy by structural damping. We review recent experiments involving biological materials on all scales, from single biopolymers over cells to model tissues, to illustrate the unifying power of this paradigm. A deliberately minimalistic yet phenomenologically very rich mathematical modeling framework for inelastic biomechanics is proposed. It transcends the conventional viscoelastic paradigm and suggests itself as a promising candidate for a unified description and interpretation of a wide range of experimental data. This article is part of a Special Issue entitled: Mechanobiology.
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Affiliation(s)
- Matti Gralka
- Institute for Theoretical Physics, University of Leipzig, Bruederstr. 16, 04103 Leipzig, Germany.
| | - Klaus Kroy
- Institute for Theoretical Physics, University of Leipzig, Bruederstr. 16, 04103 Leipzig, Germany.
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38
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Haase K, Pelling AE. Investigating cell mechanics with atomic force microscopy. J R Soc Interface 2015; 12:20140970. [PMID: 25589563 PMCID: PMC4345470 DOI: 10.1098/rsif.2014.0970] [Citation(s) in RCA: 216] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 12/18/2014] [Indexed: 12/12/2022] Open
Abstract
Transmission of mechanical force is crucial for normal cell development and functioning. However, the process of mechanotransduction cannot be studied in isolation from cell mechanics. Thus, in order to understand how cells 'feel', we must first understand how they deform and recover from physical perturbations. Owing to its versatility, atomic force microscopy (AFM) has become a popular tool to study intrinsic cellular mechanical properties. Used to directly manipulate and examine whole and subcellular reactions, AFM allows for top-down and reconstitutive approaches to mechanical characterization. These studies show that the responses of cells and their components are complex, and largely depend on the magnitude and time scale of loading. In this review, we generally describe the mechanotransductive process through discussion of well-known mechanosensors. We then focus on discussion of recent examples where AFM is used to specifically probe the elastic and inelastic responses of single cells undergoing deformation. We present a brief overview of classical and current models often used to characterize observed cellular phenomena in response to force. Both simple mechanistic models and complex nonlinear models have been used to describe the observed cellular behaviours, however a unifying description of cell mechanics has not yet been resolved.
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Affiliation(s)
- Kristina Haase
- Department of Physics, Centre for Interdisciplinary NanoPhysics, MacDonald Hall, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario, Canada
| | - Andrew E Pelling
- Department of Physics, Centre for Interdisciplinary NanoPhysics, MacDonald Hall, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario, Canada Department of Biology, Gendron Hall, 30 Marie Curie, University of Ottawa, Ottawa, Ontario, Canada Institute for Science Society and Policy, Desmarais Building, 55 Laurier Ave. East, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5
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Casares L, Vincent R, Zalvidea D, Campillo N, Navajas D, Arroyo M, Trepat X. Hydraulic fracture during epithelial stretching. NATURE MATERIALS 2015; 14:343-51. [PMID: 25664452 PMCID: PMC4374166 DOI: 10.1038/nmat4206] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 12/23/2014] [Indexed: 05/07/2023]
Abstract
The origin of fracture in epithelial cell sheets subject to stretch is commonly attributed to excess tension in the cells' cytoskeleton, in the plasma membrane, or in cell-cell contacts. Here, we demonstrate that for a variety of synthetic and physiological hydrogel substrates the formation of epithelial cracks is caused by tissue stretching independently of epithelial tension. We show that the origin of the cracks is hydraulic; they result from a transient pressure build-up in the substrate during stretch and compression manoeuvres. After pressure equilibration, cracks heal readily through actomyosin-dependent mechanisms. The observed phenomenology is captured by the theory of poroelasticity, which predicts the size and healing dynamics of epithelial cracks as a function of the stiffness, geometry and composition of the hydrogel substrate. Our findings demonstrate that epithelial integrity is determined in a tension-independent manner by the coupling between tissue stretching and matrix hydraulics.
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Affiliation(s)
- Laura Casares
- Institute for Bioengineering of Catalonia, Barcelona, Spain
| | | | | | - Noelia Campillo
- Institute for Bioengineering of Catalonia, Barcelona, Spain
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, and CIBERES, Spain
| | - Daniel Navajas
- Institute for Bioengineering of Catalonia, Barcelona, Spain
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, and CIBERES, Spain
| | - Marino Arroyo
- Universitat Politècnica de Catalunya-BarcelonaTech, Spain
- Corresponding authors: Marino Arroyo, Universitat Politècnica de Catalunya, Carrer Jordi Girona 1, 08034, Barcelona, Spain, (+34) 934 011 805, ; Xavier Trepat, Institute for Bioengineering of Catalonia, Ed. Hèlix, Baldiri i Reixac, 15-21, 08028, Barcelona, Spain, (+34) 934 020 265,
| | - Xavier Trepat
- Institute for Bioengineering of Catalonia, Barcelona, Spain
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, and CIBERES, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain
- Corresponding authors: Marino Arroyo, Universitat Politècnica de Catalunya, Carrer Jordi Girona 1, 08034, Barcelona, Spain, (+34) 934 011 805, ; Xavier Trepat, Institute for Bioengineering of Catalonia, Ed. Hèlix, Baldiri i Reixac, 15-21, 08028, Barcelona, Spain, (+34) 934 020 265,
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40
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Humphrey JD, Dufresne ER, Schwartz MA. Mechanotransduction and extracellular matrix homeostasis. Nat Rev Mol Cell Biol 2014; 15:802-12. [PMID: 25355505 PMCID: PMC4513363 DOI: 10.1038/nrm3896] [Citation(s) in RCA: 1294] [Impact Index Per Article: 129.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Soft connective tissues at steady state are dynamic; resident cells continually read environmental cues and respond to them to promote homeostasis, including maintenance of the mechanical properties of the extracellular matrix (ECM) that are fundamental to cellular and tissue health. The mechanosensing process involves assessment of the mechanics of the ECM by the cells through integrins and the actomyosin cytoskeleton, and is followed by a mechanoregulation process, which includes the deposition, rearrangement or removal of the ECM to maintain overall form and function. Progress towards understanding the molecular, cellular and tissue-level effects that promote mechanical homeostasis has helped to identify key questions for future research.
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Affiliation(s)
| | - Eric R Dufresne
- 1] Department of Mechanical Engineering, Yale University. [2] Department of Cell Biology, Yale University
| | - Martin A Schwartz
- 1] Department of Biomedical Engineering, Yale University. [2] Department of Cell Biology, Yale University. [3] Department of Medicine, Yale University, New Haven, Connecticut, 06520 USA
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41
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Boccaccio A, Lamberti L, Papi M, De Spirito M, Douet C, Goudet G, Pappalettere C. A hybrid characterization framework to determine the visco-hyperelastic properties of a porcine zona pellucida. Interface Focus 2014; 4:20130066. [PMID: 24748956 DOI: 10.1098/rsfs.2013.0066] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The zona pellucida (ZP) is a specialized extracellular matrix surrounding the developing oocyte. This thick matrix consists of various types of glycoprotein that play different roles in the fertilization process. Nowadays, several techniques are available for assessing ZP's mechanical response. The basic assumption behind these methods is that the ZP behaves like an elastic body: hence, dissipative forces are neglected and Young's modulus remains unaffected by probe dynamics. However, dissipative forces are strongly regulated by the slippage of ZP chains past one another while reaction forces related to elastic deformations (driven by the ability of each chain to stretch) depend on the ZP structure (i.e. number of cross-links and distances between knots). Although viscous reaction forces generated by the ZP are one of the main factors regulating sperm transit, their peculiar behaviour along the ZP structure remains poorly understood and rarely investigated. In order to overcome this limitation, a novel visco-hyperelastic model describing the porcine ZP reaction forces generated by nanoindentations at different probe rates is developed and verified in this study. Visco-hyperelastic parameters of porcine ZP membranes are determined by means of a hybrid characterization framework combining atomic force microscopy nanoindentation measurements, nonlinear finite-element analysis and nonlinear optimization. Remarkably, it is possible to separate the contributions of hyperelastic and viscous terms to ZP mechanical response and evaluate the error made in the determination of ZP mechanical properties if viscous effects were not considered.
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Affiliation(s)
- A Boccaccio
- Dipartimento di Meccanica , Matematica e Management , Politecnico di Bari, Bari 70126 , Italy
| | - L Lamberti
- Dipartimento di Meccanica , Matematica e Management , Politecnico di Bari, Bari 70126 , Italy
| | - M Papi
- Istituto di Fisica , Università Cattolica del Sacro Cuore , Roma 00168 , Italy
| | - M De Spirito
- Istituto di Fisica , Università Cattolica del Sacro Cuore , Roma 00168 , Italy
| | - C Douet
- UMR 85, Physiologie de la Reproduction et des Comportements , INRA-CNRS-Université de Tours , IFCE, 37380 Nouzilly , France
| | - G Goudet
- UMR 85, Physiologie de la Reproduction et des Comportements , INRA-CNRS-Université de Tours , IFCE, 37380 Nouzilly , France
| | - C Pappalettere
- Dipartimento di Meccanica , Matematica e Management , Politecnico di Bari, Bari 70126 , Italy
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Stirbat TV, Tlili S, Houver T, Rieu JP, Barentin C, Delanoë-Ayari H. Multicellular aggregates: a model system for tissue rheology. THE EUROPEAN PHYSICAL JOURNAL. E, SOFT MATTER 2013; 36:84. [PMID: 23928795 DOI: 10.1140/epje/i2013-13084-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 06/21/2013] [Indexed: 06/02/2023]
Abstract
Morphogenetic processes involve cell flows. The mechanical response of a tissue to active forces is linked to its effective viscosity. In order to decouple this mechanical response from the complex genetic changes occurring in a developing organism, we perform rheometry experiments on multicellular aggregates, which are good models for tissues. We observe a cell softening behavior when submitting to stresses. As our technique is very sensitive, we were able to get access to the measurement of a yield point above which a creep regime is observed obtained for strains above 12%. To explain our rheological curves we propose a model for the cytoskeleton that we represent as a dynamic network of parallel springs, which will break under stress and reattach at null strain. Such a simple model is able to reproduce most of the important behavior of cells under strain. We highlight here the importance of considering cells as complex fluids whose properties will vary with time according to the history of applied stress.
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Affiliation(s)
- Tomita Vasilica Stirbat
- Institut Lumière Matière, UMR5306 Université de Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne cedex, France
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Evidence of a large-scale mechanosensing mechanism for cellular adaptation to substrate stiffness. Proc Natl Acad Sci U S A 2012; 109:6933-8. [PMID: 22509005 DOI: 10.1073/pnas.1117810109] [Citation(s) in RCA: 342] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cell migration plays a major role in many fundamental biological processes, such as morphogenesis, tumor metastasis, and wound healing. As they anchor and pull on their surroundings, adhering cells actively probe the stiffness of their environment. Current understanding is that traction forces exerted by cells arise mainly at mechanotransduction sites, called focal adhesions, whose size seems to be correlated to the force exerted by cells on their underlying substrate, at least during their initial stages. In fact, our data show by direct measurements that the buildup of traction forces is faster for larger substrate stiffness, and that the stress measured at adhesion sites depends on substrate rigidity. Our results, backed by a phenomenological model based on active gel theory, suggest that rigidity-sensing is mediated by a large-scale mechanism originating in the cytoskeleton instead of a local one. We show that large-scale mechanosensing leads to an adaptative response of cell migration to stiffness gradients. In response to a step boundary in rigidity, we observe not only that cells migrate preferentially toward stiffer substrates, but also that this response is optimal in a narrow range of rigidities. Taken together, these findings lead to unique insights into the regulation of cell response to external mechanical cues and provide evidence for a cytoskeleton-based rigidity-sensing mechanism.
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44
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Waters CM, Roan E, Navajas D. Mechanobiology in lung epithelial cells: measurements, perturbations, and responses. Compr Physiol 2012; 2:1-29. [PMID: 23728969 PMCID: PMC4457445 DOI: 10.1002/cphy.c100090] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Epithelial cells of the lung are located at the interface between the environment and the organism and serve many important functions including barrier protection, fluid balance, clearance of particulate, initiation of immune responses, mucus and surfactant production, and repair following injury. Because of the complex structure of the lung and its cyclic deformation during the respiratory cycle, epithelial cells are exposed to continuously varying levels of mechanical stresses. While normal lung function is maintained under these conditions, changes in mechanical stresses can have profound effects on the function of epithelial cells and therefore the function of the organ. In this review, we will describe the types of stresses and strains in the lungs, how these are transmitted, and how these may vary in human disease or animal models. Many approaches have been developed to better understand how cells sense and respond to mechanical stresses, and we will discuss these approaches and how they have been used to study lung epithelial cells in culture. Understanding how cells sense and respond to changes in mechanical stresses will contribute to our understanding of the role of lung epithelial cells during normal function and development and how their function may change in diseases such as acute lung injury, asthma, emphysema, and fibrosis.
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45
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Pereira AM, Tudor C, Kanger JS, Subramaniam V, Martin-Blanco E. Integrin-dependent activation of the JNK signaling pathway by mechanical stress. PLoS One 2011; 6:e26182. [PMID: 22180774 PMCID: PMC3236745 DOI: 10.1371/journal.pone.0026182] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2011] [Accepted: 09/21/2011] [Indexed: 02/07/2023] Open
Abstract
Mechanical force is known to modulate the activity of the Jun N-terminal kinase (JNK) signaling cascade. However, the effect of mechanical stresses on JNK signaling activation has previously only been analyzed by in vitro detection methods. It still remains unknown how living cells activate the JNK signaling cascade in response to mechanical stress and what its functions are in stretched cells. We assessed in real-time the activity of the JNK pathway in Drosophila cells by Fluorescence Lifetime Imaging Microscopy (FLIM), using an intramolecular phosphorylation-dependent dJun-FRET (Fluorescence Resonance Energy Transfer) biosensor. We found that quantitative FRET-FLIM analysis and confocal microscopy revealed sustained dJun-FRET biosensor activation and stable morphology changes in response to mechanical stretch for Drosophila S2R+ cells. Further, these cells plated on different substrates showed distinct levels of JNK activity that associate with differences in cell morphology, integrin expression and focal adhesion organization. These data imply that alterations in the cytoskeleton and matrix attachments may act as regulators of JNK signaling, and that JNK activity might feed back to modulate the cytoskeleton and cell adhesion. We found that this dynamic system is highly plastic; at rest, integrins at focal adhesions and talin are key factors suppressing JNK activity, while multidirectional static stretch leads to integrin-dependent, and probably talin-independent, Jun sensor activation. Further, our data suggest that JNK activity has to coordinate with other signaling elements for the regulation of the cytoskeleton and cell shape remodeling associated with stretch.
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Affiliation(s)
- Andrea Maria Pereira
- Instituto de Biología Molecular de Barcelona (CSIC), Parc Cientific de Barcelona, Barcelona, Spain
| | - Cicerone Tudor
- Nanobiophysics, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Johannes S. Kanger
- Nanobiophysics, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - Vinod Subramaniam
- Nanobiophysics, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
- * E-mail: (EMB); (VS)
| | - Enrique Martin-Blanco
- Instituto de Biología Molecular de Barcelona (CSIC), Parc Cientific de Barcelona, Barcelona, Spain
- * E-mail: (EMB); (VS)
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46
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Eldib M, Dean DA. Cyclic stretch of alveolar epithelial cells alters cytoskeletal micromechanics. Biotechnol Bioeng 2011; 108:446-53. [PMID: 20830684 DOI: 10.1002/bit.22941] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Cytoplasmic transport of large molecules such as plasmid DNA (pDNA) has been shown to increase when cells are subjected to mild levels of cyclic stretch for brief periods. In the case of pDNA, this is in part due to the increased active transport of pDNA along stabilized, acetylated microtubules in the cytoplasm, whose levels are increased in response to stretch. It also has been shown that disruption of the dense actin network leads to increased pDNA and macromolecule diffusion as well. We hypothesize that stretch not only increases active transport of pDNA but also, similar to actin disrupting drugs, decreases cytoplasmic stiffness leading to a less restive pathway for macromolecules to diffuse. To test this we used particle tracking microrheology to measure cytoplasmic mechanics. We conclude that while cyclic stretch transiently decreases cytoplasmic stiffness and increases diffusivity, stretch-independent modulation of the levels of acetylated, stable microtubules has no effect on cytoplasmic stiffness. Furthermore, stretching cells that have maximally acetylated microtubules increases cytoplasmic trafficking of pDNA, without increasing levels of acetylated microtubules. These findings suggest that stretch-enhanced gene transfer may occur by two independent mechanisms: increased levels of acetylated microtubules for directed active transport, and reduced cytoplasmic stiffness for increased diffusion.
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Affiliation(s)
- Mootaz Eldib
- Department of Biomedical Engineering, University of Rochester, New York, USA
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Bernick KB, Prevost TP, Suresh S, Socrate S. Biomechanics of single cortical neurons. Acta Biomater 2011; 7:1210-9. [PMID: 20971217 DOI: 10.1016/j.actbio.2010.10.018] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 10/08/2010] [Accepted: 10/19/2010] [Indexed: 01/08/2023]
Abstract
This study presents experimental results and computational analysis of the large strain dynamic behavior of single neurons in vitro with the objective of formulating a novel quantitative framework for the biomechanics of cortical neurons. Relying on the atomic force microscopy (AFM) technique, novel testing protocols are developed to enable the characterization of neural soma deformability over a range of indentation rates spanning three orders of magnitude, 10, 1, and 0.1 μm s(-1). Modified spherical AFM probes were utilized to compress the cell bodies of neonatal rat cortical neurons in load, unload, reload and relaxation conditions. The cell response showed marked hysteretic features, strong non-linearities, and substantial time/rate dependencies. The rheological data were complemented with geometrical measurements of cell body morphology, i.e. cross-diameter and height estimates. A constitutive model, validated by the present experiments, is proposed to quantify the mechanical behavior of cortical neurons. The model aimed to correlate empirical findings with measurable degrees of (hyper)elastic resilience and viscosity at the cell level. The proposed formulation, predicated upon previous constitutive model developments undertaken at the cortical tissue level, was implemented in a three-dimensional finite element framework. The simulated cell response was calibrated to the experimental measurements under the selected test conditions, providing a novel single cell model that could form the basis for further refinements.
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Abstract
An outstanding problem in cell biology is how cells sense mechanical forces and how those forces affect cellular functions. During past decades, it has become evident that the deformable cytoskeleton (CSK), an intracellular network of various filamentous biopolymers, provides a physical basis for transducing mechanical signals into biochemical responses. To understand how mechanical forces regulate cellular functions, it is necessary to first understand how the CSK develops mechanical stresses in response to applied forces, and how those stresses are propagated through the CSK where various signaling molecules are immobilized. New experimental techniques have been developed to quantify cytoskeletal mechanics, which together with new computational approaches have given rise to new theories and models for describing mechanics of living cells. In this article, we discuss current understanding of cell biomechanics by focusing on the biophysical mechanisms that are responsible for the development and transmission of mechanical stresses in the cell and their effect on cellular functions. We compare and contrast various theories and models of cytoskeletal mechanics, emphasizing common mechanisms that those theories are built upon, while not ignoring irreconcilable differences. We highlight most recent advances in the understanding of mechanotransduction in the cytoplasm of living cells and the central role of the cytoskeletal prestress in propagating mechanical forces along the cytoskeletal filaments to activate cytoplasmic enzymes. It is anticipated that advances in cell mechanics will help developing novel therapeutics to treat pulmonary diseases like asthma, pulmonary fibrosis, and chronic obstructive pulmonary disease.
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Abstract
Cortical forces drive a variety of cell shape changes and cell movements during tissue morphogenesis. While the molecular components underlying these forces have been largely identified, how they assemble and spatially and temporally organize at cell surfaces to promote cell shape changes in developing tissues are open questions. We present here different key aspects of cortical forces: their physical nature, some rules governing their emergence, and how their deployment at cell surfaces drives important morphogenetic movements in epithelia. We review a wide range of literature combining genetic/molecular, biophysical and modeling approaches, which explore essential features of cortical force generation and transmission in tissues.
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Affiliation(s)
- Matteo Rauzi
- IBDML, UMR6216 CNRS-Université de Méditerraneé, Campus de Luminy, Case 907, 13288 Marseille Cedex 09, France
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