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Bhaskaran AM, Agrawal S, Sarkar K, Dhar P. Elasto-compliance of harmonically stimulated soft micro-gaps during electro-magneto-kinetic flows. SOFT MATTER 2024. [PMID: 39015945 DOI: 10.1039/d4sm00431k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
In this article, we develop and solve an analytical model to understand the elasto-hydrodynamic force response of a deformable, soft substrate, under dynamic loading; wherein the microfluidic gap between the substrate and load is subjected to electro-magneto-hydrodynamic interactions. As a simple physical system, we model the coupled fluid-structure-interaction characteristics when a rigid, small cylinder is permitted to impinge harmonically on an infinitely large elastic, soft substrate, and an oscillatory, squeeze flow establishes in the micro-gap formed between the two. We discuss the different observations and mechanics in terms of the governing Dukhin, Hartmann, and electroviscous numbers. The influence of electromagnetic stimuli on the flow, and its implications vis-à-vis the substrate compliance is the focus of the article. We reveal that for pure magnetohydrodynamics of the gap electrolyte, the transverse magnetic field and the induced streaming potential resist outward squeeze flow, thereby generating substantial amplifications in the force response. On the contrary, the effect of electro-magneto-hydrodynamics on the force response was strongly affected by the orientation and intensity of the transverse electric field. Notably, such variations depended significantly on the electrokinetic parameters, oscillation frequency, and substrate stiffness, whose effects were intertwined with the transverse and streaming potential electric fields. Further, possibilities of squeeze flow reversal due to opposing electromagnetic forces is observed, which may again modulate the compliance of the substrate in different mannerisms.
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Affiliation(s)
- Akshay Manoj Bhaskaran
- Hydrodynamics and Thermal Multiphysics Lab (HTML), Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, West Bengal-721302, India.
| | - Shubham Agrawal
- Hydrodynamics and Thermal Multiphysics Lab (HTML), Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, West Bengal-721302, India.
| | - Korak Sarkar
- Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, West Bengal-721302, India
| | - Purbarun Dhar
- Hydrodynamics and Thermal Multiphysics Lab (HTML), Department of Mechanical Engineering, Indian Institute of Technology Kharagpur, West Bengal-721302, India.
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2
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Robeson L, Casanova‐Morales N, Burgos‐Bravo F, Alfaro‐Valdés HM, Lesch R, Ramírez‐Álvarez C, Valdivia‐Delgado M, Vega M, Matute RA, Schekman R, Wilson CAM. Characterization of the interaction between the Sec61 translocon complex and ppαF using optical tweezers. Protein Sci 2024; 33:e4996. [PMID: 38747383 PMCID: PMC11094780 DOI: 10.1002/pro.4996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 04/03/2024] [Accepted: 04/05/2024] [Indexed: 05/19/2024]
Abstract
The Sec61 translocon allows the translocation of secretory preproteins from the cytosol to the endoplasmic reticulum lumen during polypeptide biosynthesis. These proteins possess an N-terminal signal peptide (SP) which docks at the translocon. SP mutations can abolish translocation and cause diseases, suggesting an essential role for this SP/Sec61 interaction. However, a detailed biophysical characterization of this binding is still missing. Here, optical tweezers force spectroscopy was used to characterize the kinetic parameters of the dissociation process between Sec61 and the SP of prepro-alpha-factor. The unbinding parameters including off-rate constant and distance to the transition state were obtained by fitting rupture force data to Dudko-Hummer-Szabo models. Interestingly, the translocation inhibitor mycolactone increases the off-rate and accelerates the SP/Sec61 dissociation, while also weakening the interaction. Whereas the translocation deficient mutant containing a single point mutation in the SP abolished the specificity of the SP/Sec61 binding, resulting in an unstable interaction. In conclusion, we characterize quantitatively the dissociation process between the signal peptide and the translocon, and how the unbinding parameters are modified by a translocation inhibitor.
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Affiliation(s)
- Luka Robeson
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Nathalie Casanova‐Morales
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
- Facultad de Artes LiberalesUniversidad Adolfo IbáñezSantiagoChile
| | - Francesca Burgos‐Bravo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
- California Institute for Quantitative Biosciences, Howard Hughes Medical InstituteUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - Hilda M. Alfaro‐Valdés
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Robert Lesch
- Department of Molecular and Cellular Biology, Howard Hughes Medical InstituteUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - Carolina Ramírez‐Álvarez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Mauricio Valdivia‐Delgado
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Marcela Vega
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
| | - Ricardo A. Matute
- Centro Integrativo de Biología y Química Aplicada (CIBQA)Universidad Bernardo O'HigginsSantiagoChile
- Division of Chemistry and Chemical EngineeringCalifornia Institute of TechnologyPasadenaCaliforniaUSA
| | - Randy Schekman
- Department of Molecular and Cellular Biology, Howard Hughes Medical InstituteUniversity of CaliforniaBerkeleyCaliforniaUSA
| | - Christian A. M. Wilson
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y FarmacéuticasUniversidad de ChileSantiagoChile
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3
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Liu L, Chen M, Gao Y, Tian L, Zhang W, Wang Z. Mechanism of action and side effects of colchicine based on biomechanical properties of cells. J Microsc 2023; 291:229-236. [PMID: 37358710 DOI: 10.1111/jmi.13212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Revised: 04/07/2023] [Accepted: 06/22/2023] [Indexed: 06/27/2023]
Abstract
Many diseases are related to changes in the biomechanical properties of cells; their study can provide a theoretical basis for drug screening and can explain the internal working of living cells. In this study, the biomechanical properties of nephrocytes (VERO cells), hepatocytes (HL-7702 cells), and hepatoma cells (SMCC-7721 cells) in culture were detected by atomic force microscopy (AFM) to analyse the side effects of colchicine at different concentrations (0.1 μg/mL (A) and 0.2 μg/mL (B)) at the nanoscale for 2, 4 and 6 h. Compared with the corresponding control cells, the damage to the treated cells increased in a dose-dependent manner. Among normal cells, the injury of nephrocytes (VERO cells) was markedly worse than that of hepatocytes (HL-7702 cells) in both colchicine solutions A and B. Based on the analyses of biomechanical properties, the colchicine solution reduced the rate of division and inhibited metastasis of SMCC-7721 cells. By comparing these two concentrations, we found that the anticancer effect of colchicine solution A was greater than that of solution B. Studying the mechanical properties of biological cells can help understand the mechanism of drug action at the molecular level and provide a theoretical basis for preventing the emergence and diagnosis of diseases at the nanoscale.
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Affiliation(s)
- Lanjiao Liu
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun, China
| | - Mingxin Chen
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun, China
| | - Yifan Gao
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun, China
| | - Liguo Tian
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun, China
| | - Wenxiao Zhang
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun, China
| | - Zuobin Wang
- Ministry of Education Key Laboratory for Cross-Scale Micro and Nano Manufacturing, Changchun University of Science and Technology, Changchun, China
- Institute for Research in Applicable Computing, University of Bedfordshire, Luton, UK
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4
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Borodich FM, Galanov BA, Keer LM, Suarez-Alvarez MM. Contact probing of prestressed adhesive membranes of living cells. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2021; 379:20200289. [PMID: 34148419 DOI: 10.1098/rsta.2020.0289] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/19/2020] [Indexed: 06/12/2023]
Abstract
Atomic force microscopy (AFM) studies of living biological cells is one of main experimental tools that enable quantitative measurements of deformation of the cells and extraction of information about their structural and mechanical properties. However, proper modelling of AFM probing and related adhesive contact problems are of crucial importance for interpretation of experimental data. The Johnson-Kendall-Roberts (JKR) theory of adhesive contact has often been used as a basis for modelling of various phenomena including cell-cell interactions. However, strictly speaking the original JKR theory is valid only for contact of isotropic linearly elastic spheres, while the cell membranes are often prestressed. For the first time, effects caused by molecular adhesion for living cells are analytically studied taking into account the mechanical properties of cell membranes whose stiffness depends on the level of the tensile prestress. Another important question is how one can extract the work of adhesion between the probe and the cell. An extended version of the Borodich-Galanov method for non-direct extraction of elastic and adhesive properties of contacted materials is proposed to apply to experiments of cell probing. Evidently, the proposed models of adhesive contact for cells with prestressed membranes do not cover all types of biological cells because the structure and properties of the cells may vary considerably. However, the obtained results can be applied to many types of smooth cells and can be used to describe initial stages of contact and various other processes when effects of adhesion are of crucial importance. This article is part of a discussion meeting issue 'A cracking approach to inventing new tough materials: fracture stranger than friction'.
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Affiliation(s)
| | - Boris A Galanov
- Institute for Problems in Materials Science, National Academy of Sciences of Ukraine, Kiev, Ukraine
| | - Leon M Keer
- Department of Mechanical Engineering, Northwestern University, Evanston, IL, USA
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Mojena-Medina D, Martínez-Hernández M, de la Fuente M, García-Isla G, Posada J, Jorcano JL, Acedo P. Design, Implementation, and Validation of a Piezoelectric Device to Study the Effects of Dynamic Mechanical Stimulation on Cell Proliferation, Migration and Morphology. SENSORS 2020; 20:s20072155. [PMID: 32290334 PMCID: PMC7180771 DOI: 10.3390/s20072155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 04/04/2020] [Accepted: 04/07/2020] [Indexed: 12/14/2022]
Abstract
Cell functions and behavior are regulated not only by soluble (biochemical) signals but also by biophysical and mechanical cues within the cells' microenvironment. Thanks to the dynamical and complex cell machinery, cells are genuine and effective mechanotransducers translating mechanical stimuli into biochemical signals, which eventually alter multiple aspects of their own homeostasis. Given the dominant and classic biochemical-based views to explain biological processes, it could be challenging to elucidate the key role that mechanical parameters such as vibration, frequency, and force play in biology. Gaining a better understanding of how mechanical stimuli (and their mechanical parameters associated) affect biological outcomes relies partially on the availability of experimental tools that may allow researchers to alter mechanically the cell's microenvironment and observe cell responses. Here, we introduce a new device to study in vitro responses of cells to dynamic mechanical stimulation using a piezoelectric membrane. Using this device, we can flexibly change the parameters of the dynamic mechanical stimulation (frequency, amplitude, and duration of the stimuli), which increases the possibility to study the cell behavior under different mechanical excitations. We report on the design and implementation of such device and the characterization of its dynamic mechanical properties. By using this device, we have performed a preliminary study on the effect of dynamic mechanical stimulation in a cell monolayer of an epidermal cell line (HaCaT) studying the effects of 1 Hz and 80 Hz excitation frequencies (in the dynamic stimuli) on HaCaT cell migration, proliferation, and morphology. Our preliminary results indicate that the response of HaCaT is dependent on the frequency of stimulation. The device is economic, easily replicated in other laboratories and can support research for a better understanding of mechanisms mediating cellular mechanotransduction.
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Affiliation(s)
- Dahiana Mojena-Medina
- Department of Electronics Technology, Universidad Carlos III de Madrid, 28911 Madrid, Spain; (J.P.); (P.A.)
- Correspondence:
| | - Marina Martínez-Hernández
- Department of Bioengineering and Aerospace Engineering, Universidad Carlos III de Madrid, 28911 Madrid, Spain; (M.M.-H.); (M.d.l.F.); (G.G.-I.); (J.L.J.)
| | - Miguel de la Fuente
- Department of Bioengineering and Aerospace Engineering, Universidad Carlos III de Madrid, 28911 Madrid, Spain; (M.M.-H.); (M.d.l.F.); (G.G.-I.); (J.L.J.)
| | - Guadalupe García-Isla
- Department of Bioengineering and Aerospace Engineering, Universidad Carlos III de Madrid, 28911 Madrid, Spain; (M.M.-H.); (M.d.l.F.); (G.G.-I.); (J.L.J.)
| | - Julio Posada
- Department of Electronics Technology, Universidad Carlos III de Madrid, 28911 Madrid, Spain; (J.P.); (P.A.)
| | - José Luis Jorcano
- Department of Bioengineering and Aerospace Engineering, Universidad Carlos III de Madrid, 28911 Madrid, Spain; (M.M.-H.); (M.d.l.F.); (G.G.-I.); (J.L.J.)
| | - Pablo Acedo
- Department of Electronics Technology, Universidad Carlos III de Madrid, 28911 Madrid, Spain; (J.P.); (P.A.)
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6
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Otero J, Navajas D, Alcaraz J. Characterization of the elastic properties of extracellular matrix models by atomic force microscopy. Methods Cell Biol 2019; 156:59-83. [PMID: 32222227 DOI: 10.1016/bs.mcb.2019.11.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Tissue elasticity is a critical regulator of cell behavior in normal and diseased conditions like fibrosis and cancer. Since the extracellular matrix (ECM) is a major regulator of tissue elasticity and function, several ECM-based models have emerged in the last decades, including in vitro endogenous ECM, decellularized tissue ECM and ECM hydrogels. The development of such models has urged the need to quantify their elastic properties particularly at the nanometer scale, which is the relevant length scale for cell-ECM interactions. For this purpose, the versatility of atomic force microscopy (AFM) to quantify the nanomechanical properties of soft biomaterials like ECM models has emerged as a very suitable technique. In this chapter we provide a detailed protocol on how to assess the Young's elastic modulus of ECM models by AFM, discuss some of the critical issues, and provide troubleshooting guidelines as well as illustrative examples of AFM measurements, particularly in the context of cancer.
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Affiliation(s)
- J Otero
- Unit of Biophysics and Bioengineering, Department of Biomedicine, School of Medicine and Health Sciences, Universitat de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, Spain
| | - D Navajas
- Unit of Biophysics and Bioengineering, Department of Biomedicine, School of Medicine and Health Sciences, Universitat de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, Spain; Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
| | - J Alcaraz
- Unit of Biophysics and Bioengineering, Department of Biomedicine, School of Medicine and Health Sciences, Universitat de Barcelona, Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Respiratorias (CIBERES), Instituto de Salud Carlos III, Madrid, Spain; Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain.
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7
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Chighizola M, Dini T, Lenardi C, Milani P, Podestà A, Schulte C. Mechanotransduction in neuronal cell development and functioning. Biophys Rev 2019; 11:701-720. [PMID: 31617079 PMCID: PMC6815321 DOI: 10.1007/s12551-019-00587-2] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 08/29/2019] [Indexed: 12/21/2022] Open
Abstract
Although many details remain still elusive, it became increasingly evident in recent years that mechanosensing of microenvironmental biophysical cues and subsequent mechanotransduction are strongly involved in the regulation of neuronal cell development and functioning. This review gives an overview about the current understanding of brain and neuronal cell mechanobiology and how it impacts on neurogenesis, neuronal migration, differentiation, and maturation. We will focus particularly on the events in the cell/microenvironment interface and the decisive extracellular matrix (ECM) parameters (i.e. rigidity and nanometric spatial organisation of adhesion sites) that modulate integrin adhesion complex-based mechanosensing and mechanotransductive signalling. It will also be outlined how biomaterial approaches mimicking essential ECM features help to understand these processes and how they can be used to control and guide neuronal cell behaviour by providing appropriate biophysical cues. In addition, principal biophysical methods will be highlighted that have been crucial for the study of neuronal mechanobiology.
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Affiliation(s)
- Matteo Chighizola
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Tania Dini
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Cristina Lenardi
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Paolo Milani
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Alessandro Podestà
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy
| | - Carsten Schulte
- Interdisciplinary Centre for Nanostructured Materials and Interfaces (C.I.Ma.I.Na.) and Department of Physics ``Aldo Pontremoli'', Università degli Studi di Milano, via Celoria 16, 20133, Milan, Italy.
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8
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Pellequer JL, Parot P, Navajas D, Kumar S, Svetličić V, Scheuring S, Hu J, Li B, Engler A, Sousa S, Lekka M, Szymoński M, Schillers H, Odorico M, Lafont F, Janel S, Rico F. Fifteen years of Servitude et Grandeur
to the application of a biophysical technique in medicine: The tale of AFMBioMed. J Mol Recognit 2018; 32:e2773. [DOI: 10.1002/jmr.2773] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
| | | | - Daniel Navajas
- Institute for Bioengineering of Catalonia and CIBER de Enfermedades Respiratorias; Universitat de Barcelona; Barcelona Spain
| | - Sanjay Kumar
- Departments of Bioengineering and Chemical & Biomolecular Engineering; University of California, Berkeley; Berkeley California USA
| | | | - Simon Scheuring
- Department of Anesthesiology, Department of Physiology and Biophysics; Weill Cornell Medicine; New York City New York USA
| | - Jun Hu
- Shanghai Advanced Research Institute; Chinese Academy of Sciences; Shanghai China
- Shanghai Institute of Applied Physics; Chinese Academy of Sciences; Shanghai China
| | - Bin Li
- Shanghai Advanced Research Institute; Chinese Academy of Sciences; Shanghai China
- Shanghai Institute of Applied Physics; Chinese Academy of Sciences; Shanghai China
| | - Adam Engler
- Department of Bioengineering; University of California San Diego; La Jolla California USA
| | - Susana Sousa
- i3S-Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- INEB-Instituto de Engenharia Biomédica; Universidade do Porto; Porto Portugal
- ISEP-Instituto Superior de Engenharia; Politécnico do Porto; Portugal
| | - Małgorzata Lekka
- Institute of Nuclear Physics Polish Academy of Sciences; Kraków Poland
| | - Marek Szymoński
- Center for Nanometer-scale Science and Advanced Materials, NANOSAM, Faculty of Physics, Astronomy and Applied Computer Science; Jagiellonian University; Kraków Poland
| | | | - Michael Odorico
- Institut de Chimie Séparative de Marcoule (ICSM), CEA, CNRS, ENSCM, Univ Montpellier, Marcoule; Montpellier France
| | - Frank Lafont
- Center for Infection and Immunity of Lille, CNRS UMR 8204, INSERM U1019, CHU Lille, Institut Pasteur de Lille, Univ Lille; Lille France
| | - Sebastien Janel
- Center for Infection and Immunity of Lille, CNRS UMR 8204, INSERM U1019, CHU Lille, Institut Pasteur de Lille, Univ Lille; Lille France
| | - Felix Rico
- LAI, U1067, Aix-Marseille Univ, CNRS, INSERM; Marseille France
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9
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Bidirectional mechanobiology between cells and their local extracellular matrix probed by atomic force microscopy. Semin Cell Dev Biol 2018; 73:71-81. [DOI: 10.1016/j.semcdb.2017.07.020] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 07/13/2017] [Accepted: 07/17/2017] [Indexed: 01/08/2023]
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10
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Liu L, Zhang W, Li L, Zhu X, Liu J, Wang X, Song Z, Xu H, Wang Z. Biomechanical measurement and analysis of colchicine-induced effects on cells by nanoindentation using an atomic force microscope. J Biomech 2017; 67:84-90. [PMID: 29249455 DOI: 10.1016/j.jbiomech.2017.11.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 11/23/2017] [Accepted: 11/23/2017] [Indexed: 11/17/2022]
Abstract
Colchicine is a drug commonly used for the treatment of gout, however, patients may sometimes encounter side-effects induced by taking colchicine, such as nausea, vomiting, diarrhea and kidney failure. In this regard, it is imperative to investigate the mechanism effects of colchicine on biological cells. In this paper, we present a method for the detection of mechanical properties of nephrocytes (VERO cells), hepatocytes (HL-7702 cells) and hepatoma cells (SMCC-7721 cells) in culture by atomic force microscope (AFM) to analyze the 0.1 μg/mL colchicine-induced effects on the nanoscale for two, four and six hours. Compared to the corresponding control cells, the biomechanical properties of the VERO and SMCC-7721 cells changed significantly and the HL-7702 cells did not considerably change after the treatment when considering the same time period. Based on biomechanical property analyses, the colchicine solution made the VERO and SMCC-7721 cells harder. We conclude that it is possible to reduce the division rate of the VERO cells and inhibit the metastasis of the SMCC-7721 cells. The method described here can be applied to study biomechanics of many other types of cells with different drugs. Therefore, this work provides an accurate and rapid method for drug screening and mechanical analysis of cells in medical research.
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Affiliation(s)
- Lanjiao Liu
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Wenxiao Zhang
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Li Li
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Xinyao Zhu
- School of Engineering, University of Warwick, Coventry CV4 7AL, UK
| | - Jinyun Liu
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China; Joint Research Centre for Computer-Controlled Nanomanufacturing, University of Bedfordshire, Luton LU1 3JU, UK
| | - Xinyue Wang
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Zhengxun Song
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Hongmei Xu
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China
| | - Zuobin Wang
- International Research Centre for Nano Handling and Manufacturing of China, Changchun University of Science and Technology, Changchun 130022, China; Joint Research Centre for Computer-Controlled Nanomanufacturing, University of Bedfordshire, Luton LU1 3JU, UK.
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11
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Burgos-Bravo F, Figueroa NL, Casanova-Morales N, Quest AFG, Wilson CAM, Leyton L. Single-molecule measurements of the effect of force on Thy-1/αvβ3-integrin interaction using nonpurified proteins. Mol Biol Cell 2017; 29:326-338. [PMID: 29212879 PMCID: PMC5996956 DOI: 10.1091/mbc.e17-03-0133] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 10/10/2017] [Accepted: 12/01/2017] [Indexed: 12/11/2022] Open
Abstract
Single-molecule measurements combined with a novel mathematical strategy were applied to accurately characterize how bimolecular interactions respond to mechanical force, especially when protein purification is not possible. Specifically, we studied the effect of force on Thy-1/αvβ3 integrin interaction, a mediator of neuron-astrocyte communication. Thy-1 and αvβ3 integrin mediate bidirectional cell-to-cell communication between neurons and astrocytes. Thy-1/αvβ3 interactions stimulate astrocyte migration and the retraction of neuronal prolongations, both processes in which internal forces are generated affecting the bimolecular interactions that maintain cell–cell adhesion. Nonetheless, how the Thy-1/αvβ3 interactions respond to mechanical cues is an unresolved issue. In this study, optical tweezers were used as a single-molecule force transducer, and the Dudko-Hummer-Szabo model was applied to calculate the kinetic parameters of Thy-1/αvβ3 dissociation. A novel experimental strategy was implemented to analyze the interaction of Thy-1-Fc with nonpurified αvβ3-Fc integrin, whereby nonspecific rupture events were corrected by using a new mathematical approach. This methodology permitted accurately estimating specific rupture forces for Thy-1-Fc/αvβ3-Fc dissociation and calculating the kinetic and transition state parameters. Force exponentially accelerated Thy-1/αvβ3 dissociation, indicating slip bond behavior. Importantly, nonspecific interactions were detected even for purified proteins, highlighting the importance of correcting for such interactions. In conclusion, we describe a new strategy to characterize the response of bimolecular interactions to forces even in the presence of nonspecific binding events. By defining how force regulates Thy-1/αvβ3 integrin binding, we provide an initial step towards understanding how the neuron–astrocyte pair senses and responds to mechanical cues.
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Affiliation(s)
- Francesca Burgos-Bravo
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies of Exercise, Metabolism and Cancer, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile
| | - Nataniel L Figueroa
- Physics Department, Pontificia Universidad Católica de Chile, 782-0436 Santiago, Chile
| | - Nathalie Casanova-Morales
- Biochemistry and Molecular Biology Department, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 838-0494 Santiago, Chile
| | - Andrew F G Quest
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies of Exercise, Metabolism and Cancer, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile
| | - Christian A M Wilson
- Biochemistry and Molecular Biology Department, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 838-0494 Santiago, Chile
| | - Lisette Leyton
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile .,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies of Exercise, Metabolism and Cancer, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile
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12
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Yango A, Schäpe J, Rianna C, Doschke H, Radmacher M. Measuring the viscoelastic creep of soft samples by step response AFM. SOFT MATTER 2016; 12:8297-8306. [PMID: 27714302 DOI: 10.1039/c6sm00801a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We have measured the creep response of soft gels and cells after applying a step in loading force with atomic force microscopy (AFM). By analysing the creep response data using the standard linear solid model, we can quantify the viscous and elastic properties of these soft samples independently. Cells, in comparison with gels of similar softness, are much more viscous, as has been qualitatively observed in conventional force curve data before. Here, we quantify the spring constant and the viscous damping coefficient from the creep response data. We propose two different modes for applying a force step: (1) indirectly by increasing the sample height or (2) directly by employing magnetic cantilevers. Both lead to similar results, whereas the latter seems to be better defined since it resembles closely a constant strain mode. The former is easier to implement in most instruments, and thus may be preferable from a practical point of view. Creep analysis by step response is much more appropriate to analyse the viscoelastic response of soft samples like cells than the usually used force curve analysis.
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Affiliation(s)
- Achu Yango
- Institute of Biophysics, University of Bremen, Otto-Hahn Allee 1, 28359 Bremen, Germany.
| | - Jens Schäpe
- Institute of Biophysics, University of Bremen, Otto-Hahn Allee 1, 28359 Bremen, Germany.
| | - Carmela Rianna
- Institute of Biophysics, University of Bremen, Otto-Hahn Allee 1, 28359 Bremen, Germany.
| | - Holger Doschke
- Institute of Biophysics, University of Bremen, Otto-Hahn Allee 1, 28359 Bremen, Germany.
| | - Manfred Radmacher
- Institute of Biophysics, University of Bremen, Otto-Hahn Allee 1, 28359 Bremen, Germany.
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13
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Gavara N. A beginner's guide to atomic force microscopy probing for cell mechanics. Microsc Res Tech 2016; 80:75-84. [PMID: 27676584 PMCID: PMC5217064 DOI: 10.1002/jemt.22776] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 08/17/2016] [Accepted: 08/22/2016] [Indexed: 12/17/2022]
Abstract
Atomic Force microscopy (AFM) is becoming a prevalent tool in cell biology and biomedical studies, especially those focusing on the mechanical properties of cells and tissues. The newest generation of bio-AFMs combine ease of use and seamless integration with live-cell epifluorescence or more advanced optical microscopies. As a unique feature with respect to other bionanotools, AFM provides nanometer-resolution maps for cell topography, stiffness, viscoelasticity, and adhesion, often overlaid with matching optical images of the probed cells. This review is intended for those about to embark in the use of bio-AFMs, and aims to assist them in designing an experiment to measure the mechanical properties of adherent cells. In addition to describing the main steps in a typical cell mechanics protocol and explaining how data is analysed, this review will also discuss some of the relevant contact mechanics models available and how they have been used to characterize specific features of cellular and biological samples. Microsc. Res. Tech. 80:75-84, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Núria Gavara
- School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London, E1 3NS, UK
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14
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Valero C, Navarro B, Navajas D, García-Aznar JM. Finite element simulation for the mechanical characterization of soft biological materials by atomic force microscopy. J Mech Behav Biomed Mater 2016; 62:222-235. [PMID: 27214690 DOI: 10.1016/j.jmbbm.2016.05.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 04/28/2016] [Accepted: 05/04/2016] [Indexed: 12/30/2022]
Affiliation(s)
- C Valero
- Multiscale in Mechanical and Biological Engineering (M2BE), Aragon Institute of Engineering Research, Department of Mechanical Engineering, University of Zaragoza, Zaragoza, Spain.
| | - B Navarro
- Multiscale in Mechanical and Biological Engineering (M2BE), Aragon Institute of Engineering Research, Department of Mechanical Engineering, University of Zaragoza, Zaragoza, Spain
| | - D Navajas
- Institute for Bioengineering of Catalonia, 08028 Barcelona, Spain; Centro de Investigación Biomédica en Red de Enfermedades Respiratorias, 28029 Madrid, Spain; Facultat de Medicina, Universitat de Barcelona, 08036 Barcelona, Spain
| | - J M García-Aznar
- Multiscale in Mechanical and Biological Engineering (M2BE), Aragon Institute of Engineering Research, Department of Mechanical Engineering, University of Zaragoza, Zaragoza, Spain
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15
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Giménez A, Uriarte JJ, Vieyra J, Navajas D, Alcaraz J. Elastic properties of hydrogels and decellularized tissue sections used in mechanobiology studies probed by atomic force microscopy. Microsc Res Tech 2016; 80:85-96. [PMID: 27535539 DOI: 10.1002/jemt.22740] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Revised: 07/15/2016] [Accepted: 07/19/2016] [Indexed: 12/26/2022]
Abstract
The increasing recognition that tissue elasticity is an important regulator of cell behavior in normal and pathologic conditions such as fibrosis and cancer has driven the development of cell culture substrata with tunable elasticity. Such development has urged the need to quantify the elastic properties of these cell culture substrata particularly at the nanometer scale, since this is the relevant length scale involved in cell-extracellular matrix (ECM) mechanical interactions. To address this need, we have exploited the versatility of atomic force microscopy to quantify the elastic properties of a variety of cell culture substrata used in mechanobiology studies, including floating collagen gels, ECM-coated polyacrylamide gels, and decellularized tissue sections. In this review we summarize major findings in this field from our group within the context of the state-of-the-art in the field, and provide a critical discussion on the applicability and complementarity of currently available cell culture assays with tunable elasticity. In addition, we briefly describe how the limitations of these assays provide opportunities for future research, which is expected to continue expanding our understanding of the mechanobiological aspects that support both normal and diseased conditions. Microsc. Res. Tech. 80:85-96, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Alícia Giménez
- Unitat de Biofísica i Bioenginyeria, Departament de Biomedicina, Facultat de Medicina, Universitat de Barcelona, Barcelona, 08036, Spain
| | - Juan José Uriarte
- Unitat de Biofísica i Bioenginyeria, Departament de Biomedicina, Facultat de Medicina, Universitat de Barcelona, Barcelona, 08036, Spain
| | - Joan Vieyra
- Unitat de Biofísica i Bioenginyeria, Departament de Biomedicina, Facultat de Medicina, Universitat de Barcelona, Barcelona, 08036, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Departament de Biomedicina, Facultat de Medicina, Universitat de Barcelona, Barcelona, 08036, Spain.,Institut de Bioenginyeria de Catalunya (IBEC), Barcelona, 08028, Spain.,CIBER de Enfermedades Respiratorias (CIBERES), Madrid, 28029, Spain
| | - Jordi Alcaraz
- Unitat de Biofísica i Bioenginyeria, Departament de Biomedicina, Facultat de Medicina, Universitat de Barcelona, Barcelona, 08036, Spain.,CIBER de Enfermedades Respiratorias (CIBERES), Madrid, 28029, Spain
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16
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Liu Y, Wang Z, Wang X, Huang Y. Quantitative analysis of dynamic adhesion properties in human hepatocellular carcinoma cells with fullerenol. Micron 2015; 79:74-83. [DOI: 10.1016/j.micron.2015.08.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 07/27/2015] [Accepted: 08/22/2015] [Indexed: 11/17/2022]
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17
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Liu Y, Wang Z, Wang X. AFM-Based Study of Fullerenol (C 60 (OH) 24 )-Induced Changes of Elasticity in Living SMCC-7721 Cells. J Mech Behav Biomed Mater 2015; 45:65-74. [DOI: 10.1016/j.jmbbm.2014.12.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2014] [Revised: 12/08/2014] [Accepted: 12/10/2014] [Indexed: 10/24/2022]
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18
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Schimpel C, Werzer O, Fröhlich E, Leitinger G, Absenger-Novak M, Teubl B, Zimmer A, Roblegg E. Atomic force microscopy as analytical tool to study physico-mechanical properties of intestinal cells. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2015. [PMID: 26199850 PMCID: PMC4505173 DOI: 10.3762/bjnano.6.151] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/14/2023]
Abstract
The small intestine is a complex system that carries out various functions. The main function of enterocytes is absorption of nutrients, whereas membranous cells (M cells) are responsible for delivering antigens/foreign substances to the mucosal lymphoid tissues. However, to get a fundamental understanding of how cellular structures contribute to physiological processes, precise knowledge about surface morphologies, cytoskeleton organizations and biomechanical properties is necessary. Atomic force microscopy (AFM) was used here as a powerful tool to study surface topographies of Caco-2 cells and M cells. Furthermore, cell elasticity (i.e., the mechanical response of a cell on a tip indentation), was elucidated by force curve measurements. Besides elasticity, adhesion was evaluated by recording the attraction and repulsion forces between the tip and the cell surface. Organization of F-actin networks were investigated via phalloidin labeling and visualization was performed with confocal laser scanning fluorescence microscopy (CLSM) and scanning electron microscopy (SEM). The results of these various experimental techniques revealed significant differences in the cytoskeleton/microvilli arrangements and F-actin organization. Caco-2 cells displayed densely packed F-actin bundles covering the entire cell surface, indicating the formation of a well-differentiated brush border. In contrast, in M cells actins were arranged as short and/or truncated thin villi, only available at the cell edge. The elasticity of M cells was 1.7-fold higher compared to Caco-2 cells and increased significantly from the cell periphery to the nuclear region. Since elasticity can be directly linked to cell adhesion, M cells showed higher adhesion forces than Caco-2 cells. The combination of distinct experimental techniques shows that morphological differences between Caco-2 cells and M cells correlate with mechanical cell properties and provide useful information to understand physiological processes/mechanisms in the small intestine.
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Affiliation(s)
- Christa Schimpel
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical Technology, NAWI Graz, Karl-Franzens-University of Graz, BioTechMed-Graz, Austria
| | - Oliver Werzer
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical Technology, NAWI Graz, Karl-Franzens-University of Graz, BioTechMed-Graz, Austria
| | - Eleonore Fröhlich
- Medical University of Graz, Center for Medical Research, BioTechMed-Graz, Austria
| | - Gerd Leitinger
- Research Unit Electron Microscopic Techniques, Institute of Cell Biology, Histology and Embryology, Center for Medical Research, Medical University of Graz, BioTechMed-Graz, Austria
| | | | - Birgit Teubl
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical Technology, NAWI Graz, Karl-Franzens-University of Graz, BioTechMed-Graz, Austria
| | - Andreas Zimmer
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical Technology, NAWI Graz, Karl-Franzens-University of Graz, BioTechMed-Graz, Austria
| | - Eva Roblegg
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical Technology, NAWI Graz, Karl-Franzens-University of Graz, BioTechMed-Graz, Austria
- Research Center Pharmaceutical Engineering GmbH, Graz, Austria
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19
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Guo D, Li J, Xie G, Wang Y, Luo J. Elastic properties of polystyrene nanospheres evaluated with atomic force microscopy: size effect and error analysis. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:7206-12. [PMID: 24892186 DOI: 10.1021/la501485e] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The mechanical properties of polystyrene (PS) nanospheres of ca. 50-1000 nm in diameter were evaluated by using an atomic force microscope (AFM). The compressive elastic moduli of individual nanospheres were obtained by analyzing the AFM force-displacement curves on the basis of the Hertz and JKR contact theories. The results showed that the elastic moduli of PS nanospheres of different sizes were in the range of 2-8 GPa. The elastic modulus of PS nanospheres increased with the decrease of the sphere diameter, especially when the diameter was less than 200 nm. The measurement errors due to tip wear and the deformation at the bottom of the sphere were analyzed. Mechanisms for the size dependence on the elastic modulus of PS nanospheres were also discussed.
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Affiliation(s)
- Dan Guo
- State Key Laboratory of Tribology, Tsinghua University , Beijing 10084, China
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20
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Picas L, Milhiet PE, Hernández-Borrell J. Atomic force microscopy: a versatile tool to probe the physical and chemical properties of supported membranes at the nanoscale. Chem Phys Lipids 2012. [PMID: 23194897 DOI: 10.1016/j.chemphyslip.2012.10.005] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Atomic force microscopy (AFM) was developed in the 1980s following the invention of its precursor, scanning tunneling microscopy (STM), earlier in the decade. Several modes of operation have evolved, demonstrating the extreme versatility of this method for measuring the physicochemical properties of samples at the nanoscopic scale. AFM has proved an invaluable technique for visualizing the topographic characteristics of phospholipid monolayers and bilayers, such as roughness, height or laterally segregated domains. Implemented modes such as phase imaging have also provided criteria for discriminating the viscoelastic properties of different supported lipid bilayer (SLB) regions. In this review, we focus on the AFM force spectroscopy (FS) mode, which enables determination of the nanomechanical properties of membrane models. The interpretation of force curves is presented, together with newly emerging techniques that provide complementary information on physicochemical properties that may contribute to our understanding of the structure and function of biomembranes. Since AFM is an imaging technique, some basic indications on how real-time AFM imaging is evolving are also presented at the end of this paper.
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Affiliation(s)
- Laura Picas
- Institut Curie, CNRS UMR 144, 26 rue d'Ulm, 75248 Paris, France
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21
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Roca-Cusachs P, Iskratsch T, Sheetz MP. Finding the weakest link: exploring integrin-mediated mechanical molecular pathways. J Cell Sci 2012; 125:3025-38. [PMID: 22797926 DOI: 10.1242/jcs.095794] [Citation(s) in RCA: 176] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
From the extracellular matrix to the cytoskeleton, a network of molecular links connects cells to their environment. Molecules in this network transmit and detect mechanical forces, which subsequently determine cell behavior and fate. Here, we reconstruct the mechanical pathway followed by these forces. From matrix proteins to actin through integrins and adaptor proteins, we review how forces affect the lifetime of bonds and stretch or alter the conformation of proteins, and how these mechanical changes are converted into biochemical signals in mechanotransduction events. We evaluate which of the proteins in the network can participate in mechanotransduction and which are simply responsible for transmitting forces in a dynamic network. Besides their individual properties, we also analyze how the mechanical responses of a protein are determined by their serial connections from the matrix to actin, their parallel connections in integrin clusters and by the rate at which force is applied to them. All these define mechanical molecular pathways in cells, which are emerging as key regulators of cell function alongside better studied biochemical pathways.
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Affiliation(s)
- Pere Roca-Cusachs
- University of Barcelona and Institute for Bioengineering of Catalonia, Barcelona, Spain.
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22
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Ay C, Yeh CC, Hsu MC, Hurng HY, Kwok PCL, Chang HI. Evaluation of the correlation between focal adhesion kinase phosphorylation and cell adhesion force using "DEP" technology. SENSORS 2012; 12:5951-65. [PMID: 22778624 PMCID: PMC3386723 DOI: 10.3390/s120505951] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2012] [Revised: 04/24/2012] [Accepted: 04/28/2012] [Indexed: 11/24/2022]
Abstract
Dielectrophoresis (DEP) is the phenomenon in which a particle, such as a living cell, is polarized and moved by electrical gravity in a non-uniform electric field. In the present study, the DEP force is utilized to act on the cells to induce spatial movement for investigating the correlation between the cell adhesion force and activation level of focal adhesion kinase (FAK). The DEP force produced by the non-uniform electric field was used to measure the cell adhesion force of ECV304 cells, on type 1 collagen (COL1)- and fibronectin (FN)-coated polydimethylsiloxane (PDMS) membranes. For COL1-coating, ECV304 cells revealed weak and variable adhesion force (0.343–0.760 nN) in the first eight hours of incubation. Interestingly, the cell adhesion force of ECV304 at two and five hours of cultivation was significantly high and matched their FAK activation level. In comparison, ECV304 on FN-coated membrane had higher and more stable cell adhesion force (0.577–2.053 nN). FN coating intensified the cell adhesion force of ECV304 with culture time and similar outcome was present on the activation level of FAK. Therefore, this study demonstrated a relationship between cell adhesion force and FAK activation level that was dependant on the choice of the extracellular matrix (ECM) component. Subsequently, two tyrosine kinase inhibitors (AG18 and genistein) and one PI3K inhibitor (LY294002) were applied to study the influence of protein phosphorylation on the cell adhesion force. FAK plays an important role on cell attachment and DEP force measurement is a useful technique for studying cell adhesion.
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Affiliation(s)
- Chyung Ay
- Department of Biomechatronic Engineering, National Chiayi University, No. 300, University Road, East District, Chiayi 600, Taiwan; E-Mails: (C.A.); (M.-C.H.); (H.-Y.H.)
| | - Chih-Chang Yeh
- Department of Orthopaedics, Chiayi Branch, Taichung Veterans General Hospital, No.600, Sec. 2, Shixian Road, West District, Chiayi City 60090, Taiwan; E-Mail:
| | - Min-Chih Hsu
- Department of Biomechatronic Engineering, National Chiayi University, No. 300, University Road, East District, Chiayi 600, Taiwan; E-Mails: (C.A.); (M.-C.H.); (H.-Y.H.)
| | - Huaang-Youh Hurng
- Department of Biomechatronic Engineering, National Chiayi University, No. 300, University Road, East District, Chiayi 600, Taiwan; E-Mails: (C.A.); (M.-C.H.); (H.-Y.H.)
| | - Philip Chi Lip Kwok
- Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong; E-Mail:
| | - Hsin-I. Chang
- Department of Biomechatronic Engineering, National Chiayi University, No. 300, University Road, East District, Chiayi 600, Taiwan; E-Mails: (C.A.); (M.-C.H.); (H.-Y.H.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +886-5-271-7923; Fax: +886-5-271-7780
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23
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Acerbi I, Luque T, Giménez A, Puig M, Reguart N, Farré R, Navajas D, Alcaraz J. Integrin-specific mechanoresponses to compression and extension probed by cylindrical flat-ended AFM tips in lung cells. PLoS One 2012; 7:e32261. [PMID: 22384196 PMCID: PMC3285695 DOI: 10.1371/journal.pone.0032261] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 01/24/2012] [Indexed: 01/08/2023] Open
Abstract
Cells from lung and other tissues are subjected to forces of opposing directions that are largely transmitted through integrin-mediated adhesions. How cells respond to force bidirectionality remains ill defined. To address this question, we nanofabricated flat-ended cylindrical Atomic Force Microscopy (AFM) tips with ~1 µm(2) cross-section area. Tips were uncoated or coated with either integrin-specific (RGD) or non-specific (RGE/BSA) molecules, brought into contact with lung epithelial cells or fibroblasts for 30 s to form focal adhesion precursors, and used to probe cell resistance to deformation in compression and extension. We found that cell resistance to compression was globally higher than to extension regardless of the tip coating. In contrast, both tip-cell adhesion strength and resistance to compression and extension were the highest when probed at integrin-specific adhesions. These integrin-specific mechanoresponses required an intact actin cytoskeleton, and were dependent on tyrosine phosphatases and Ca(2+) signaling. Cell asymmetric mechanoresponse to compression and extension remained after 5 minutes of tip-cell adhesion, revealing that asymmetric resistance to force directionality is an intrinsic property of lung cells, as in most soft tissues. Our findings provide new insights on how lung cells probe the mechanochemical properties of the microenvironment, an important process for migration, repair and tissue homeostasis.
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Affiliation(s)
- Irene Acerbi
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
- Laboratorio di Tecnologie Biomediche, Dipartimento di Bioingegneria, Politecnico di Milano, Milano, Italy
- Institut de Bioenginyeria de Catalunya (IBEC), Barcelona, Spain
| | - Tomás Luque
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
- Institut de Bioenginyeria de Catalunya (IBEC), Barcelona, Spain
| | - Alícia Giménez
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
| | - Marta Puig
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
| | - Noemi Reguart
- CIBER de Enfermedades Respiratorias (CIBERES), Bunyola, Spain
| | - Ramon Farré
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
- Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Bunyola, Spain
| | - Daniel Navajas
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
- Institut de Bioenginyeria de Catalunya (IBEC), Barcelona, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Bunyola, Spain
| | - Jordi Alcaraz
- Unitat de Biofísica i Bioenginyeria, Facultat de Medicina, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Respiratorias (CIBERES), Bunyola, Spain
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24
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Shen Y, Ahmad MR, Nakajima M, Kojima S, Homma M, Fukuda T. Evaluation of the single yeast cell's adhesion to ITO substrates with various surface energies via ESEM nanorobotic manipulation system. IEEE Trans Nanobioscience 2012; 10:217-24. [PMID: 22249767 DOI: 10.1109/tnb.2011.2177099] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Cell-surface adhesion force is important for cell activities and the development of bio materials. In this paper, a method for in situ single cell (W303) adhesion force measurement was proposed based on nanorobotic manipulation system inside an environment scanning electron microscope (ESEM). An end effector was fabricated from a commercial atomic force microscope (AFM) cantilever by focused ion beam (FIB) etching. The spring constant of it was calibrated by nanomanipulation approach. Three kinds of hydrophilic and hydrophobic ITO plates were prepared by using VUV-irradiation and OTS coating techniques. The shear adhesion strength of the single yeast cell to each substrate was measured based on the deflection of the end effector. The results demonstrated that the cell adhesion force was larger under the wet condition in the ESEM environment than in the aqueous condition. It also showed that the cell adhesion force to hydrophilic surface was larger than that to the hydrophobic surface. Studies of single cell's adhesion on various plate surfaces and environments could give new insights into the tissue engineering and biological field.
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Affiliation(s)
- Yajing Shen
- Department of Micro-Nano Systems Engineering, Nagoya University, Nagoya, Japan.
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25
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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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26
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Alcaraz J, Mori H, Ghajar CM, Brownfield D, Galgoczy R, Bissell MJ. Collective epithelial cell invasion overcomes mechanical barriers of collagenous extracellular matrix by a narrow tube-like geometry and MMP14-dependent local softening. Integr Biol (Camb) 2011; 3:1153-66. [PMID: 21993836 DOI: 10.1039/c1ib00073j] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Collective cell invasion (CCI) through interstitial collagenous extracellular matrix (ECM) is crucial to the initial stages of branching morphogenesis, and a hallmark of tissue repair and dissemination of certain tumors. The collagenous ECM acts as a mechanical barrier against CCI. However, the physical nature of this barrier and how it is overcome by cells remains incompletely understood. To address these questions, we performed theoretical and experimental analysis of mammary epithelial branching morphogenesis in 3D type I collagen (collagen-I) gels. We found that the mechanical resistance of collagen-I is largely due to its elastic rather than its viscous properties. We also identified two strategies utilized by mammary epithelial cells that can independently minimize ECM mechanical resistance during CCI. First, cells adopt a narrow tube-like geometry during invasion, which minimizes the elastic opposition from the ECM as revealed by theoretical modeling of the most frequent invasive shapes and sizes. Second, the stiffness of the collagenous ECM is reduced at invasive fronts due to its degradation by matrix metalloproteinases (MMPs), as indicated by direct measurements of collagen-I microelasticity by atomic force microscopy. Molecular techniques further specified that the membrane-bound MMP14 mediates degradation of collagen-I at invasive fronts. Thus, our findings reveal that MMP14 is necessary to efficiently reduce the physical restraints imposed by collagen-I during branching morphogenesis, and help our overall understanding of how forces are balanced between cells and their surrounding ECM to maintain collective geometry and mechanical stability during CCI.
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Affiliation(s)
- Jordi Alcaraz
- Life Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, MS 977R225A, Berkeley, CA 94720, USA
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Three powerful research tools from single cells into single molecules: AFM, laser tweezers, and Raman spectroscopy. Appl Biochem Biotechnol 2011; 165:485-96. [PMID: 21556902 DOI: 10.1007/s12010-011-9267-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2010] [Accepted: 04/18/2011] [Indexed: 01/11/2023]
Abstract
By using three physical techniques (atomic force microscopy (AFM), laser tweezers, and Raman spectroscopy), many excellent works in single-cell/molecule research have been accomplished. In this review, we present a brief introduction to the principles of these three techniques, and their capabilities toward single-cell/molecule research are highlighted. Afterward, the advances in single-cell/molecule research that have been facilitated by these three techniques are described. Following this, their complementary assets for single-cell/molecule research are analyzed, and the necessity of integrating the functions of these three techniques into one instrument is proposed.
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Casuso I, Rico F, Scheuring S. Biological AFM: where we come from - where we are - where we may go. J Mol Recognit 2011; 24:406-13. [DOI: 10.1002/jmr.1081] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Rico F, Chu C, Abdulreda MH, Qin Y, Moy VT. Temperature modulation of integrin-mediated cell adhesion. Biophys J 2010; 99:1387-96. [PMID: 20816050 PMCID: PMC2931747 DOI: 10.1016/j.bpj.2010.06.037] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2010] [Revised: 06/02/2010] [Accepted: 06/14/2010] [Indexed: 10/19/2022] Open
Abstract
In response to external stimuli, cells modulate their adhesive state by regulating the number and intrinsic affinity of receptor/ligand bonds. A number of studies have shown that cell adhesion is dramatically reduced at room or lower temperatures as compared with physiological temperature. However, the underlying mechanism that modulates adhesion is still unclear. Here, we investigated the adhesion of the monocytic cell line THP-1 to a surface coated with intercellular adhesion molecule-1 (ICAM-1) as a function of temperature. THP-1 cells express the integrin lymphocyte function-associated antigen-1 (LFA-1), a receptor for ICAM-1. Direct force measurements of cell adhesion and cell elasticity were carried out by atomic force microscopy. Force measurements revealed an increase of the work of de-adhesion with temperature that was coupled to a gradual decrease in cellular stiffness. Of interest, single-molecule measurements revealed that the rupture force of the LFA-1/ICAM-1 complex decreased with temperature. A detailed analysis of the force curves indicated that temperature-modulated cell adhesion was mainly due to the enhanced ability of cells to deform and to form a greater number of longer membrane tethers at physiological temperatures. Together, these results emphasize the importance of cell mechanics and membrane-cytoskeleton interaction on the modulation of cell adhesion.
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Affiliation(s)
- Félix Rico
- Department of Physiology and Biophysics, University of Miami, Miller School of Medicine, Miami, Florida, USA.
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Ziebarth NM, Rico F, Moy VT. Structural and Mechanical Mechanisms of Ocular Tissues Probed by AFM. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/978-3-642-03535-7_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Zhu J, Sabharwal T, Kalyanasundaram A, Guo L, Wang G. Topographic mapping and compression elasticity analysis of skinned cardiac muscle fibers in vitro with atomic force microscopy and nanoindentation. J Biomech 2009; 42:2143-50. [PMID: 19640539 PMCID: PMC2808505 DOI: 10.1016/j.jbiomech.2009.05.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 05/08/2009] [Accepted: 05/23/2009] [Indexed: 10/20/2022]
Abstract
Surface topography and compression elasticity of bovine cardiac muscle fibers in rigor and relaxing state have been studied with atomic force microscopy. Characteristic sarcomere patterns running along the longitudinal axis of the fibers were clearly observed, and Z-lines, M-lines, I-bands, and A-bands can be distinguished through comparing with TEM images and force curves. AFM height images of fibers had shown a sarcomere length of 1.22+/-0.02 microm (n=5) in rigor with a significant 9% increase in sarcomere length in relaxing state (1.33+/-0.03 microm, n=5), indicating that overlap moves with the changing physiological conditions. Compression elasticity curves along with sarcomere locations have been taken by AFM compression processing. Coefficient of Z-line, I-band, Overlap, and M-line are 25+/-2, 8+/-1, 10+/-1, and 17+/-1.5 pN/nm respectively in rigor state, and 18+/-2.5, 4+/-0.5, 6+/-1, and 11+/-0.5 pN/nm respectively in relaxing state. Young's Modulus in Z-line, I-band, Overlap, and M-line are 115+/-12, 48+/-9, 52+/-8, and 90+/-12 kPa respectively in rigor, and 98+/-10, 23+/-4, 42+/-4, and 65+/-7 kPa respectively in relaxing state. The elasticity curves have shown a similar appearance to the section analysis profile of AFM height images of sarcomere and the distance between adjacent largest coefficient and Young's Modulus is equal to the sarcomere length measured from the AFM height images using section analysis, indicating that mechanic properties of fibers have a similar periodicity to the topography of fibers.
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Affiliation(s)
- Jie Zhu
- Cardiac Biophysics and Bioengineering Laboratory, College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
- Biophysics Collaborative Access Team, Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439-4860, United States
- Pritzker Institute of Biomedical Science & Engineering, Illinois Institute of Technology, Chicago, IL 60616-3793, United States
| | - Tanya Sabharwal
- Pritzker Institute of Biomedical Science & Engineering, Illinois Institute of Technology, Chicago, IL 60616-3793, United States
- Section of Molecular Cell and Developmental Biology, School of Biological Sciences, University of Texas, Austin, TX 78712, United States
| | - Aruna Kalyanasundaram
- Pritzker Institute of Biomedical Science & Engineering, Illinois Institute of Technology, Chicago, IL 60616-3793, United States
| | - Lianhong Guo
- Laboratory of Biomathematics, Department of Applied Mathematics, Northwest A&F University, Yangling, Shaanxi 712100, China
- Department of Applied Mathematics, College of Science and Letters, Illinois Institute of Technology, Chicago, IL 60616, United States
| | - Guodong Wang
- Cardiac Biophysics and Bioengineering Laboratory, College of Science, Northwest A&F University, Yangling, Shaanxi 712100, China
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Kang S, Elimelech M. Bioinspired single bacterial cell force spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:9656-9659. [PMID: 19634872 DOI: 10.1021/la902247w] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We developed a method for preparing live bacterial cell probes for atomic force microscopy (AFM) using a bioinspired polydopamine wet adhesive. Microscopic examinations with bacterial and yeast cells indicated that cells were successfully glued to the end of the AFM cantilevers and remained viable for the duration of the force measurements. Interaction forces measured with live single-cell microorganism probes differed markedly from those obtained with glutaraldehyde-fixed microorganism probes. Interaction forces between live cell probes and quartz surfaces involved both repulsive steric forces and multimodal weak adhesion forces, which were attributed to the soft exocellular polymeric layers and the heterogeneity of the cell membrane surfaces.
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Affiliation(s)
- Seoktae Kang
- Department of Chemical Engineering, Environmental Engineering Program, Yale University, New Haven, Connecticut 06520-8286, USA
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Tripathy S, Berger EJ. Measuring Viscoelasticity of Soft Samples Using Atomic Force Microscopy. J Biomech Eng 2009; 131:094507. [DOI: 10.1115/1.3194752] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Relaxation indentation experiments using atomic force microscopy (AFM) are used to obtain viscoelastic material properties of soft samples. The quasilinear viscoelastic (QLV) model formulated by Fung (1972, “Stress Strain History Relations of Soft Tissues in Simple Elongation,” in Biomechanics, Its Foundation and Objectives, Prentice-Hall, Englewood Cliffs, NJ, pp. 181–207) for uniaxial compression data was modified for the indentation test data in this study. Hertz contact mechanics was used for the instantaneous deformation, and a reduced relaxation function based on continuous spectrum is used for the time-dependent part in the model. The modified QLV indentation model presents a novel method to obtain viscoelastic properties from indentation data independent of relaxation times of the test. The major objective of the present study is to develop the QLV indentation model and implement the model on AFM indentation data for 1% agarose gel and a viscoelastic polymer using spherical indenter.
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Affiliation(s)
- S. Tripathy
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904
| | - E. J. Berger
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904
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Wang K, Solis-Wever X, Aguas C, Liu Y, Li P, Pappas D. Differential Mobility Cytometry. Anal Chem 2009; 81:3334-43. [DOI: 10.1021/ac900277y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Kelong Wang
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Ximena Solis-Wever
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Charmaine Aguas
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Yan Liu
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Peng Li
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
| | - Dimitri Pappas
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061
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