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Arricca M, Salvadori A, Bonanno C, Serpelloni M. Modeling Receptor Motility along Advecting Lipid Membranes. MEMBRANES 2022; 12:membranes12070652. [PMID: 35877855 PMCID: PMC9317916 DOI: 10.3390/membranes12070652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/21/2022] [Accepted: 06/21/2022] [Indexed: 11/24/2022]
Abstract
This work aims to overview multiphysics mechanobiological computational models for receptor dynamics along advecting cell membranes. Continuum and statistical models of receptor motility are the two main modeling methodologies identified in reviewing the state of the art. Within the former modeling class, a further subdivision based on different biological purposes and processes of proteins’ motion is recognized; cell adhesion, cell contractility, endocytosis, and receptor relocations on advecting membranes are the most relevant biological processes identified in which receptor motility is pivotal. Numerical and/or experimental methods and approaches are highlighted in the exposure of the reviewed works provided by the literature, pertinent to the topic of the present manuscript. With a main focus on the continuum models of receptor motility, we discuss appropriate multiphyisics laws to model the mass flux of receptor proteins in the reproduction of receptor relocation and recruitment along cell membranes to describe receptor–ligand chemical interactions, and the cell’s structural response. The mass flux of receptor modeling is further supported by a discussion on the methodology utilized to evaluate the protein diffusion coefficient developed over the years.
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Affiliation(s)
- Matteo Arricca
- The Mechanobiology Research Center, University of Brescia (UNIBS), 25123 Brescia, Italy; (M.A.); (C.B.); (M.S.)
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, via Branze 38, 25123 Brescia, Italy
| | - Alberto Salvadori
- The Mechanobiology Research Center, University of Brescia (UNIBS), 25123 Brescia, Italy; (M.A.); (C.B.); (M.S.)
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, via Branze 38, 25123 Brescia, Italy
- Correspondence:
| | - Claudia Bonanno
- The Mechanobiology Research Center, University of Brescia (UNIBS), 25123 Brescia, Italy; (M.A.); (C.B.); (M.S.)
- Department of Civil, Environmental, Architectural Engineering and Mathematics, Università degli Studi di Brescia, via Branze 43, 25123 Brescia, Italy
| | - Mattia Serpelloni
- The Mechanobiology Research Center, University of Brescia (UNIBS), 25123 Brescia, Italy; (M.A.); (C.B.); (M.S.)
- Department of Mechanical and Industrial Engineering, Università degli Studi di Brescia, via Branze 38, 25123 Brescia, Italy
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2
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Souissi M, Pernier J, Rossier O, Giannone G, Le Clainche C, Helfer E, Sengupta K. Integrin-Functionalised Giant Unilamellar Vesicles via Gel-Assisted Formation: Good Practices and Pitfalls. Int J Mol Sci 2021; 22:6335. [PMID: 34199292 PMCID: PMC8231826 DOI: 10.3390/ijms22126335] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 05/26/2021] [Accepted: 06/08/2021] [Indexed: 01/16/2023] Open
Abstract
Giant unilamellar vesicles (GUV) are powerful tools to explore physics and biochemistry of the cell membrane in controlled conditions. For example, GUVs were extensively used to probe cell adhesion, but often using non-physiological linkers, due to the difficulty of incorporating transmembrane adhesion proteins into model membranes. Here we describe a new protocol for making GUVs incorporating the transmembrane protein integrin using gel-assisted swelling. We report an optimised protocol, enumerating the pitfalls encountered and precautions to be taken to maintain the robustness of the protocol. We characterise intermediate steps of small proteoliposome formation and the final formed GUVs. We show that the integrin molecules are successfully incorporated and are functional.
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Affiliation(s)
- Mariem Souissi
- Aix Marseille Univ, CNRS, Centre Interdisciplinaire de Nanoscience de Marseille (CINAM), Turing Centre for Living Systems, 13009 Marseille, France;
| | - Julien Pernier
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France; (J.P.); (C.L.C.)
| | - Olivier Rossier
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, 33000 Bordeaux, France; (O.R.); (G.G.)
| | - Gregory Giannone
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, 33000 Bordeaux, France; (O.R.); (G.G.)
| | - Christophe Le Clainche
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France; (J.P.); (C.L.C.)
| | - Emmanuèle Helfer
- Aix Marseille Univ, CNRS, Centre Interdisciplinaire de Nanoscience de Marseille (CINAM), Turing Centre for Living Systems, 13009 Marseille, France;
| | - Kheya Sengupta
- Aix Marseille Univ, CNRS, Centre Interdisciplinaire de Nanoscience de Marseille (CINAM), Turing Centre for Living Systems, 13009 Marseille, France;
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3
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Li L, Stumpf BH, Smith AS. Molecular Biomechanics Controls Protein Mixing and Segregation in Adherent Membranes. Int J Mol Sci 2021; 22:3699. [PMID: 33918167 PMCID: PMC8037219 DOI: 10.3390/ijms22073699] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 03/22/2021] [Accepted: 03/25/2021] [Indexed: 01/28/2023] Open
Abstract
Cells interact with their environment by forming complex structures involving a multitude of proteins within assemblies in the plasma membrane. Despite the omnipresence of these assemblies, a number of questions about the correlations between the organisation of domains and the biomechanical properties of the involved proteins, namely their length, flexibility and affinity, as well as about the coupling to the elastic, fluctuating membrane, remain open. Here we address these issues by developing an effective Kinetic Monte Carlo simulation to model membrane adhesion. We apply this model to a typical experiment in which a cell binds to a functionalized solid supported bilayer and use two ligand-receptor pairs to study these couplings. We find that differences in affinity and length of proteins forming adhesive contacts result in several characteristic features in the calculated phase diagrams. One such feature is mixed states occurring even with proteins with length differences of 10 nm. Another feature are stable nanodomains with segregated proteins appearing on time scales of cell experiments, and for biologically relevant parameters. Furthermore, we show that macroscopic ring-like patterns can spontaneously form as a consequence of emergent protein fluxes. The capacity to form domains is captured by an order parameter that is founded on the virial coefficients for the membrane mediated interactions between bonds, which allow us to collapse all the data. These findings show that taking into account the role of the membrane allows us to recover a number of experimentally observed patterns. This is an important perspective in the context of explicit biological systems, which can now be studied in significant detail.
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Affiliation(s)
- Long Li
- PULS Group, Institute for Theoretical Physics and Interdisciplinary Center for Nanostructured Films, Friedrich-Alexander-University Erlangen-Nürnberg, Cauerstrasse 3, 91058 Erlangen, Germany; (L.L.); (B.H.S.)
- Key Laboratory of Mechanics on Disaster and Environment in Western China, Ministry of Education, College of Civil Engineering and Mechanics, Lanzhou University, Lanzhou 730000, China
| | - Bernd Henning Stumpf
- PULS Group, Institute for Theoretical Physics and Interdisciplinary Center for Nanostructured Films, Friedrich-Alexander-University Erlangen-Nürnberg, Cauerstrasse 3, 91058 Erlangen, Germany; (L.L.); (B.H.S.)
| | - Ana-Sunčana Smith
- PULS Group, Institute for Theoretical Physics and Interdisciplinary Center for Nanostructured Films, Friedrich-Alexander-University Erlangen-Nürnberg, Cauerstrasse 3, 91058 Erlangen, Germany; (L.L.); (B.H.S.)
- Group for Computational Life Sciences, Division of Physical Chemistry, Ruđer Bošković Institute, Bijenička cesta, 10000 Zagreb, Croatia
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4
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Tolosa-Díaz A, Almendro-Vedia VG, Natale P, López-Montero I. The GDP-Bound State of Mitochondrial Mfn1 Induces Membrane Adhesion of Apposing Lipid Vesicles through a Cooperative Binding Mechanism. Biomolecules 2020; 10:biom10071085. [PMID: 32708307 PMCID: PMC7407159 DOI: 10.3390/biom10071085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 07/10/2020] [Accepted: 07/17/2020] [Indexed: 01/01/2023] Open
Abstract
Mitochondria are double-membrane organelles that continuously undergo fission and fusion. Outer mitochondrial membrane fusion is mediated by the membrane proteins mitofusin 1 (Mfn1) and mitofusin 2 (Mfn2), carrying a GTP hydrolyzing domain (GTPase) and two coiled-coil repeats. The detailed mechanism on how the GTP hydrolysis allows Mfns to approach adjacent membranes into proximity and promote their fusion is currently under debate. Using model membranes built up as giant unilamellar vesicles (GUVs), we show here that Mfn1 promotes membrane adhesion of apposing lipid vesicles. The adhesion forces were sustained by the GDP-bound state of Mfn1 after GTP hydrolysis. In contrast, the incubation with the GDP:AlF4−, which mimics the GTP transition state, did not induce membrane adhesion. Due to the flexible nature of lipid membranes, the adhesion strength depended on the surface concentration of Mfn1 through a cooperative binding mechanism. We discuss a possible scenario for the outer mitochondrial membrane fusion based on the modulated action of Mfn1.
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Affiliation(s)
- Andrés Tolosa-Díaz
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
| | - Víctor G. Almendro-Vedia
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
| | - Paolo Natale
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
- Correspondence: (P.N.); (I.L.-M.)
| | - Iván López-Montero
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
- Correspondence: (P.N.); (I.L.-M.)
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Witt H, Vache M, Cordes A, Janshoff A. Detachment of giant liposomes - coupling of receptor mobility and membrane shape. SOFT MATTER 2020; 16:6424-6433. [PMID: 32588015 DOI: 10.1039/d0sm00863j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Cellular adhesion is an intricate physical process controlled by ligand-receptor affinity, density, mobility, and external forces transmitted through the elastic properties of the cell. As a model for cellular adhesion we study the detachment of cell-sized liposomes and membrane-coated silica beads from supported bilayers using atomic force microscopy. Adhesion between the two surfaces is mediated by the interaction between the adhesive lipid anchored saccharides lactosylceramide and the ganglioside GM3. We found that force-distance curves of liposome detachment have a very peculiar, partially concave shape, reminiscent of the nonlinear extension of polymers. By contrast, detachment of membrane coated beads led to force-distance curves similar to the detachment of living cells. Theoretical modelling of the enforced detachment suggests that the non-convex force curve shape arises from the mobility of ligands provoking a switch of shapes from spherical to unduloidal during detachment.
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Affiliation(s)
- Hannes Witt
- Max Planck Institute for Dynamics and Self-Organization, Am Faßberg, 37077 Göttingen, Germany
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Karimi F, Thombare VJ, Hutton CA, O'Connor AJ, Qiao GG, Heath DE. Biomaterials functionalized with nanoclusters of integrin- and syndecan-binding ligands improve cell adhesion and mechanosensing under shear flow conditions. J Biomed Mater Res A 2020; 109:313-325. [PMID: 32490581 DOI: 10.1002/jbm.a.37024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 04/20/2020] [Accepted: 04/27/2020] [Indexed: 12/11/2022]
Abstract
We have engineered biomaterials that display nanoclusters of ligands that bind both integrin and syndecan-4 cell receptors. These surfaces regulate cell behaviors under static conditions including adhesion, spreading, actin stress fiber formation, and migration. The syndecan-4 receptors are also critical mediators of cellular mechanotransduction. In this contribution we assess whether this novel class of materials can regulate the response of cells to applied mechanical stimulation, using the shear stress imparted by laminar fluid flow as a model stimulus. Specifically, we assess endothelial cell detachment due to flow, cell alignment due to flow, and cell adhesion from the flowing fluid. A high degree of cell retention was observed on surfaces containing integrin-binding ligands or a mixed population of integrin- and syndecan-binding ligands. However, the presence of both ligand types was necessary for the cells to align in the direction of flow. These results imply that integrin engagement is necessary for adhesion strength, but engagement of both receptor types aids in appropriate mechanotransduction. Additionally, it was found that surfaces functionalized with both ligand types were able to scavenge a larger number of cells from flow, and to do so at a faster rate, compared to surfaces functionalized with only integrin- or syndecan-binding ligands. These results show that interfaces functionalized with both integrin- and syndecan-binding ligands regulate a significant range of biophysical cell behaviors in response to shear stress.
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Affiliation(s)
- Fatemeh Karimi
- Department of Biomedical Engineering, Particulate Fluids Processing Centre, University of Melbourne, Parkville, Victoria, Australia.,Polymer Science Group, Department of Chemical Engineering, Particulate Fluid Processing Centre, University of Melbourne, Parkville, Victoria, Australia.,Graduate School of Biomedical Engineering, University of New South Wales, Sydney, Australia
| | - Varsha Jagannath Thombare
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
| | - Craig A Hutton
- School of Chemistry and Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia
| | - Andrea J O'Connor
- Department of Biomedical Engineering, Particulate Fluids Processing Centre, University of Melbourne, Parkville, Victoria, Australia
| | - Greg G Qiao
- Polymer Science Group, Department of Chemical Engineering, Particulate Fluid Processing Centre, University of Melbourne, Parkville, Victoria, Australia
| | - Daniel E Heath
- Department of Biomedical Engineering, Particulate Fluids Processing Centre, University of Melbourne, Parkville, Victoria, Australia
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7
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Rodríguez-García R, Volkov VA, Chen CY, Katrukha EA, Olieric N, Aher A, Grigoriev I, López MP, Steinmetz MO, Kapitein LC, Koenderink G, Dogterom M, Akhmanova A. Mechanisms of Motor-Independent Membrane Remodeling Driven by Dynamic Microtubules. Curr Biol 2020; 30:972-987.e12. [PMID: 32032506 PMCID: PMC7090928 DOI: 10.1016/j.cub.2020.01.036] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 12/09/2019] [Accepted: 01/10/2020] [Indexed: 12/26/2022]
Abstract
Microtubule-dependent organization of membranous organelles occurs through motor-based pulling and by coupling microtubule dynamics to membrane remodeling. For example, tubules of endoplasmic reticulum (ER) can be extended by kinesin- and dynein-mediated transport and through the association with the tips of dynamic microtubules. The binding between ER and growing microtubule plus ends requires End Binding (EB) proteins and the transmembrane protein STIM1, which form a tip-attachment complex (TAC), but it is unknown whether these proteins are sufficient for membrane remodeling. Furthermore, EBs and their partners undergo rapid turnover at microtubule ends, and it is unclear how highly transient protein-protein interactions can induce load-bearing processive motion. Here, we reconstituted membrane tubulation in a minimal system with giant unilamellar vesicles, dynamic microtubules, an EB protein, and a membrane-bound protein that can interact with EBs and microtubules. We showed that these components are sufficient to drive membrane remodeling by three mechanisms: membrane tubulation induced by growing microtubule ends, motor-independent membrane sliding along microtubule shafts, and membrane pulling by shrinking microtubules. Experiments and modeling demonstrated that the first two mechanisms can be explained by adhesion-driven biased membrane spreading on microtubules. Optical trapping revealed that growing and shrinking microtubule ends can exert forces of ∼0.5 and ∼5 pN, respectively, through attached proteins. Rapidly exchanging molecules that connect membranes to dynamic microtubules can thus bear a sufficient load to induce membrane deformation and motility. Furthermore, combining TAC components and a membrane-attached kinesin in the same in vitro assays demonstrated that they can cooperate in promoting membrane tubule extension.
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Affiliation(s)
- Ruddi Rodríguez-García
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, Utrecht 3584, the Netherlands
| | - Vladimir A Volkov
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, Delft 2629, the Netherlands
| | - Chiung-Yi Chen
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, Utrecht 3584, the Netherlands
| | - Eugene A Katrukha
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, Utrecht 3584, the Netherlands
| | - Natacha Olieric
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, Forschungsstrasse 111, Villigen 5232, Switzerland
| | - Amol Aher
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, Utrecht 3584, the Netherlands
| | - Ilya Grigoriev
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, Utrecht 3584, the Netherlands
| | | | - Michel O Steinmetz
- Laboratory of Biomolecular Research, Division of Biology and Chemistry, Paul Scherrer Institut, Forschungsstrasse 111, Villigen 5232, Switzerland; University of Basel, Biozentrum, Klingelbergstrasse, Basel 4056, Switzerland
| | - Lukas C Kapitein
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, Utrecht 3584, the Netherlands
| | - Gijsje Koenderink
- Department of Living Matter, AMOLF, Science Park 104, Amsterdam 1098, the Netherlands
| | - Marileen Dogterom
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Van der Maasweg 9, Delft 2629, the Netherlands.
| | - Anna Akhmanova
- Cell Biology, Department of Biology, Faculty of Science, Utrecht University, Padualaan 8, Utrecht 3584, the Netherlands.
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8
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Liu H, Fang C, Gong Z, Chang RCC, Qian J, Gao H, Lin Y. Fundamental Characteristics of Neuron Adhesion Revealed by Forced Peeling and Time-Dependent Healing. Biophys J 2020; 118:1811-1819. [PMID: 32197062 DOI: 10.1016/j.bpj.2020.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 02/17/2020] [Accepted: 03/02/2020] [Indexed: 01/19/2023] Open
Abstract
A current bottleneck in the advance of neurophysics is the lack of reliable methods to quantitatively measure the interactions between neural cells and their microenvironment. Here, we present an experimental technique to probe the fundamental characteristics of neuron adhesion through repeated peeling of well-developed neurite branches on a substrate with an atomic force microscopy cantilever. At the same time, a total internal reflection fluorescence microscope is also used to monitor the activities of neural cell adhesion molecules (NCAMs) during detaching. It was found that NCAMs aggregate into clusters at the neurite-substrate interface, resulting in strong local attachment with an adhesion energy of ∼0.1 mJ/m2 and sudden force jumps in the recorded force-displacement curve. Furthermore, by introducing a healing period between two forced peelings, we showed that stable neurite-substrate attachment can be re-established in 2-5 min. These findings are rationalized by a stochastic model, accounting for the breakage and rebinding of NCAM-based molecular bonds along the interface, and provide new insights into the mechanics of neuron adhesion as well as many related biological processes including axon outgrowth and nerve regeneration.
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Affiliation(s)
- Haipei Liu
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Chao Fang
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Ze Gong
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China
| | - Raymond Chuen-Chung Chang
- Laboratory of Neurodegenerative Diseases, School of Biomedical Sciences, LKS Faculty of Medicine, and State Key Laboratory of Brain and Cognitive Sciences, The University of Hong Kong, Hong Kong, China
| | - Jin Qian
- Department of Engineering Mechanics, Zhejiang University, Hangzhou, Zhejiang, China
| | - Huajian Gao
- School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore.
| | - Yuan Lin
- Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China.
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9
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Frey F, Ziebert F, Schwarz US. Dynamics of particle uptake at cell membranes. Phys Rev E 2019; 100:052403. [PMID: 31869989 DOI: 10.1103/physreve.100.052403] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Indexed: 11/07/2022]
Abstract
Receptor-mediated endocytosis requires that the energy of adhesion overcomes the deformation energy of the plasma membrane. The resulting driving force is balanced by dissipative forces, leading to deterministic dynamical equations. While the shape of the free membrane does not play an important role for tensed and loose membranes, in the intermediate regime it leads to an important energy barrier. Here we show that this barrier is similar to but different from an effective line tension and suggest a simple analytical approximation for it. We then explore the rich dynamics of uptake for particles of different shapes and present the corresponding dynamical state diagrams. We also extend our model to include stochastic fluctuations, which facilitate uptake and lead to corresponding changes in the phase diagrams.
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Affiliation(s)
- Felix Frey
- Institute for Theoretical Physics, Heidelberg University, Philosophenweg 19, 69120 Heidelberg, Germany and BioQuant, Heidelberg University, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany
| | - Falko Ziebert
- Institute for Theoretical Physics, Heidelberg University, Philosophenweg 19, 69120 Heidelberg, Germany and BioQuant, Heidelberg University, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany
| | - Ulrich S Schwarz
- Institute for Theoretical Physics, Heidelberg University, Philosophenweg 19, 69120 Heidelberg, Germany and BioQuant, Heidelberg University, Im Neuenheimer Feld 267, 69120 Heidelberg, Germany
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10
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Tunable cell-surface mimetics as engineered cell substrates. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2018; 1860:2076-2093. [PMID: 29935145 DOI: 10.1016/j.bbamem.2018.06.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Revised: 05/18/2018] [Accepted: 06/08/2018] [Indexed: 12/21/2022]
Abstract
Most recent breakthroughs in understanding cell adhesion, cell migration, and cellular mechanosensitivity have been made possible by the development of engineered cell substrates of well-defined surface properties. Traditionally, these substrates mimic the extracellular matrix (ECM) environment by the use of ligand-functionalized polymeric gels of adjustable stiffness. However, such ECM mimetics are limited in their ability to replicate the rich dynamics found at cell-cell contacts. This review focuses on the application of cell surface mimetics, which are better suited for the analysis of cell adhesion, cell migration, and cellular mechanosensitivity across cell-cell interfaces. Functionalized supported lipid bilayer systems were first introduced as biomembrane-mimicking substrates to study processes of adhesion maturation during adhesion of functionalized vesicles (cell-free assay) and plated cells. However, while able to capture adhesion processes, the fluid lipid bilayer of such a relatively simple planar model membrane prevents adhering cells from transducing contractile forces to the underlying solid, making studies of cell migration and cellular mechanosensitivity largely impractical. Therefore, the main focus of this review is on polymer-tethered lipid bilayer architectures as biomembrane-mimicking cell substrate. Unlike supported lipid bilayers, these polymer-lipid composite materials enable the free assembly of linkers into linker clusters at cellular contacts without hindering cell spreading and migration and allow the controlled regulation of mechanical properties, enabling studies of cellular mechanosensitivity. The various polymer-tethered lipid bilayer architectures and their complementary properties as cell substrates are discussed.
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11
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Tehrani M, Sarvestani AS. Force-driven growth of intercellular junctions. J Theor Biol 2017; 421:101-111. [PMID: 28377302 DOI: 10.1016/j.jtbi.2017.03.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Revised: 03/28/2017] [Accepted: 03/29/2017] [Indexed: 10/19/2022]
Abstract
Mechanical force regulates the formation and growth of cell-cell junctions. Cadherin is a prominent homotypic cell adhesion molecule that plays a crucial role in establishment of intercellular adhesion. It is known that the transmitted force through the cadherin-mediated junctions directly correlates with the growth and enlargement of the junctions. In this paper, we propose a physical model for the structural evolution of cell-cell junctions subjected to pulling tractions, using the Bell-Dembo-Bongard thermodynamic model. Cadherins have multiple adhesive states and may establish slip or catch bonds depending on the Ca2+ concentration. We conducted a comparative study between the force-dependent behavior of clusters of slip and catch bonds. The results show that the clusters of catch bonds feature some hallmarks of cell mechanotransduction in response to the pulling traction. This is a passive thermodynamic response and is entirely controlled by the effect of mechanical work of the pulling force on the free energy landscape of the junction.
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Affiliation(s)
- Mohammad Tehrani
- Department of Mechanical Engineering, Ohio University, Athens, OH 45701, United States
| | - Alireza S Sarvestani
- Department of Mechanical Engineering, Ohio University, Athens, OH 45701, United States.
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12
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Gou X, Wang R, Lam SSY, Hou J, Leung AYH, Sun D. Cell adhesion manipulation through single cell assembly for characterization of initial cell-to-cell interaction. Biomed Eng Online 2015; 14:114. [PMID: 26652601 PMCID: PMC4676142 DOI: 10.1186/s12938-015-0109-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 11/28/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cell-to-cell interactions are complex processes that involve physical interactions, chemical binding, and biological signaling pathways. Identification of the functions of special signaling pathway in cell-to-cell interaction from the very first contact will help characterize the mechanism underlying the interaction and advance new drug discovery. METHODS This paper reported a case study of characterizing initial interaction between leukemia cancer cells and bone marrow stromal cells, through the use of an optical tweezers-based cell manipulation tool. Optical traps were used to assemble leukemia cells at different positions of the stromal cell layer and enable their interactions by applying a small trapping force to maintain the cell contact for a few minutes. Specific drug was used to inhibit the binding of molecules during receptor-ligand-mediated adhesion. RESULTS AND CONCLUSIONS Our results showed that the amount of adhesion molecule could affect cell adhesion during the first few minutes contact. We also found that leukemia cancer cells could migrate on the stromal cell layer, which was dependent on the adhesion state and activation triggered by specific chemokine. The reported approaches provided a new opportunity to investigate cell-to-cell interaction through single cell adhesion manipulation.
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Affiliation(s)
- Xue Gou
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
| | - Ran Wang
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
| | - Stephen S Y Lam
- Department of Medicine, The University of Hong Kong, Hong Kong, China.
| | - Jundi Hou
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
| | - Anskar Y H Leung
- Department of Medicine, The University of Hong Kong, Hong Kong, China.
| | - Dong Sun
- Department of Mechanical and Biomedical Engineering, City University of Hong Kong, Hong Kong, China.
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13
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Gordon VD, O'Halloran TJ, Shindell O. Membrane adhesion and the formation of heterogeneities: biology, biophysics, and biotechnology. Phys Chem Chem Phys 2015; 17:15522-33. [PMID: 25866854 PMCID: PMC4465551 DOI: 10.1039/c4cp05876c] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Membrane adhesion is essential to many vital biological processes. Sites of membrane adhesion are often associated with heterogeneities in the lipid and protein composition of the membrane. These heterogeneities are thought to play functional roles by facilitating interactions between proteins. However, the causal links between membrane adhesion and membrane heterogeneities are not known. Here we survey the state of the field and indicate what we think are understudied areas ripe for development.
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Affiliation(s)
- V D Gordon
- The University of Texas at Austin, Department of Physics and Center for Nonlinear Dynamics, 2515 Speedway, Stop C1610, Austin, Texas 78712-1199, USA.
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14
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Schmidt D, Bihr T, Fenz S, Merkel R, Seifert U, Sengupta K, Smith AS. Crowding of receptors induces ring-like adhesions in model membranes. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2015; 1853:2984-91. [PMID: 26028591 DOI: 10.1016/j.bbamcr.2015.05.025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Revised: 05/21/2015] [Accepted: 05/22/2015] [Indexed: 10/23/2022]
Abstract
The dynamics of formation of macromolecular structures in adherent membranes is a key to a number of cellular processes. However, the interplay between protein reaction kinetics, diffusion and the morphology of the growing domains, governed by membrane mediated interactions, is still poorly understood. Here we show, experimentally and in simulations, that a rich phase diagram emerges from the competition between binding, cooperativity, molecular crowding and membrane spreading. In the cellular context, the spontaneously-occurring organization of adhesion domains in ring-like morphologies is particularly interesting. These are stabilized by the crowding of bulky proteins, and the membrane-transmitted correlations between bonds. Depending on the density of the receptors, this phase may be circumvented, and instead, the adhesions may grow homogeneously in the contact zone between two membranes. If the development of adhesion occurs simultaneously with membrane spreading, much higher accumulation of binders can be achieved depending on the velocity of spreading. The mechanisms identified here, in the context of our mimetic model, may shed light on the structuring of adhesions in the contact zones between two living cells. This article is part of a Special Issue entitled: Mechanobiology.
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Affiliation(s)
- Daniel Schmidt
- Institut für Theoretische Physik and Cluster of Excellence: Engineering of Advanced Materials, Friedrich Alexander Universität Erlangen-Nürnberg, 91052 Erlangen, Germany; II. Institut für Theoretische Physik, Universität Stuttgart, 70569 Stuttgart, Germany
| | - Timo Bihr
- Institut für Theoretische Physik and Cluster of Excellence: Engineering of Advanced Materials, Friedrich Alexander Universität Erlangen-Nürnberg, 91052 Erlangen, Germany; II. Institut für Theoretische Physik, Universität Stuttgart, 70569 Stuttgart, Germany
| | - Susanne Fenz
- Institute of Complex Systems 7: Biomechanics, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany; Lehrstuhl für Zell- und Entwicklungsbiologie (Zoologie I), Biozentrum der Universität Würzburg, 97074 Würzburg, Germany
| | - Rudolf Merkel
- Institute of Complex Systems 7: Biomechanics, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Udo Seifert
- II. Institut für Theoretische Physik, Universität Stuttgart, 70569 Stuttgart, Germany
| | - Kheya Sengupta
- Aix-Marseille Université, CNRS, CINaM UMR 7325, 13288 Marseille, France
| | - Ana-Sunčana Smith
- Institut für Theoretische Physik and Cluster of Excellence: Engineering of Advanced Materials, Friedrich Alexander Universität Erlangen-Nürnberg, 91052 Erlangen, Germany; Insitut Ruđer Bošković, 10000 Zagreb, Croatia.
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15
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Samadi-Dooki A, Shodja HM, Malekmotiei L. The effect of the physical properties of the substrate on the kinetics of cell adhesion and crawling studied by an axisymmetric diffusion-energy balance coupled model. SOFT MATTER 2015; 11:3693-3705. [PMID: 25823723 DOI: 10.1039/c5sm00394f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this paper an analytical approach to study the effect of the substrate physical properties on the kinetics of adhesion and motility behavior of cells is presented. Cell adhesion is mediated by the binding of cell wall receptors and substrate's complementary ligands, and tight adhesion is accomplished by the recruitment of the cell wall binders to the adhesion zone. The binders' movement is modeled as their axisymmetric diffusion in the fluid-like cell membrane. In order to preserve the thermodynamic consistency, the energy balance for the cell-substrate interaction is imposed on the diffusion equation. Solving the axisymmetric diffusion-energy balance coupled equations, it turns out that the physical properties of the substrate (substrate's ligand spacing and stiffness) have considerable effects on the cell adhesion and motility kinetics. For a rigid substrate with uniform distribution of immobile ligands, the maximum ligand spacing which does not interrupt adhesion growth is found to be about 57 nm. It is also found that as a consequence of the reduction in the energy dissipation in the isolated adhesion system, cell adhesion is facilitated by increasing substrate's stiffness. Moreover, the directional movement of cells on a substrate with gradients in mechanical compliance is explored with an extension of the adhesion formulation. It is shown that cells tend to move from soft to stiff regions of the substrate, but their movement is decelerated as the stiffness of the substrate increases. These findings based on the proposed theoretical model are in excellent agreement with the previous experimental observations.
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Affiliation(s)
- Aref Samadi-Dooki
- Department of Civil Engineering, Sharif University of Technology, P.O. Box 11155-9313, Tehran, Iran
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16
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Kralj-Iglič V. Membrane Microvesiculation and its Suppression. ADVANCES IN PLANAR LIPID BILAYERS AND LIPOSOMES 2015. [DOI: 10.1016/bs.adplan.2015.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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17
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Shindell O, Mica N, Ritzer M, Gordon VD. Specific adhesion of membranes simultaneously supports dual heterogeneities in lipids and proteins. Phys Chem Chem Phys 2015; 17:15598-607. [DOI: 10.1039/c4cp05877a] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Membrane adhesion mediated by one protein species simultaneously stabilizes both ordered-phase and disordered-phase heterogeneities, distinct from the non-adhered membrane.
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Affiliation(s)
- O. Shindell
- The University of Texas at Austin
- Department of Physics and Center for Nonlinear Dynamics
- Austin
- USA
| | - N. Mica
- The University of Texas at Austin
- Department of Physics and Center for Nonlinear Dynamics
- Austin
- USA
| | - M. Ritzer
- The University of Texas at Austin
- Department of Physics and Center for Nonlinear Dynamics
- Austin
- USA
| | - V. D. Gordon
- The University of Texas at Austin
- Department of Physics and Center for Nonlinear Dynamics
- Austin
- USA
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18
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Bihr T, Fenz S, Sackmann E, Merkel R, Seifert U, Sengupta K, Smith AS. Association rates of membrane-coupled cell adhesion molecules. Biophys J 2014; 107:L33-6. [PMID: 25468354 PMCID: PMC4255260 DOI: 10.1016/j.bpj.2014.10.033] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 10/13/2014] [Accepted: 10/24/2014] [Indexed: 11/20/2022] Open
Abstract
Thus far, understanding how the confined cellular environment affects the lifetime of bonds, as well as the extraction of complexation rates, has been a major challenge in studies of cell adhesion. Based on a theoretical description of the growth curves of adhesion domains, we present a new (to our knowledge) method to measure the association rate k(on) of ligand-receptor pairs incorporated into lipid membranes. As a proof of principle, we apply this method to several systems. We find that the k(on) for the interaction of biotin with neutravidin is larger than that for integrin binding to RGD or sialyl Lewis(x) to E-selectin. Furthermore, we find k(on) to be enhanced by membrane fluctuations that increase the probability for encounters between the binders. The opposite effect on k(on) could be attributed to the presence of repulsive polymers that mimic the glycocalyx, which points to two potential mechanisms for controlling the speed of protein complexation during the cell recognition process.
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Affiliation(s)
- Timo Bihr
- Institut für Theoretische Physik and Cluster of Excellence Engineering of Advanced Materials, Friedrich-Alexander-Universität, Erlangen, Germany; II. Institut für Theoretische Physik, Universität Stuttgart, Stuttgart, Germany
| | - Susanne Fenz
- Institute of Complex Systems 7: Biomechanics Forschungszentrum Jülich, Jülich, Germany; Department of Cell and Developmental Biology, Theodor-Boveri-Institute, Universität Würzburg, Würzburg, Germany
| | - Erich Sackmann
- Physics Department, Biophysics E22, Technische Universität München, München, Germany
| | - Rudolf Merkel
- Institute of Complex Systems 7: Biomechanics Forschungszentrum Jülich, Jülich, Germany
| | - Udo Seifert
- II. Institut für Theoretische Physik, Universität Stuttgart, Stuttgart, Germany
| | - Kheya Sengupta
- Aix-Marseille Université, CNRS, CINaM UMR 7325, Marseille, France
| | - Ana-Sunčana Smith
- Institut für Theoretische Physik and Cluster of Excellence Engineering of Advanced Materials, Friedrich-Alexander-Universität, Erlangen, Germany; Institute Ruđer Bošković, Division of Physical Chemistry, Zagreb, Croatia.
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19
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Körner A, Deichmann C, Rossetti FF, Köhler A, Konovalov OV, Wedlich D, Tanaka M. Cell differentiation of pluripotent tissue sheets immobilized on supported membranes displaying cadherin-11. PLoS One 2013; 8:e54749. [PMID: 23424619 PMCID: PMC3570561 DOI: 10.1371/journal.pone.0054749] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 12/14/2012] [Indexed: 12/12/2022] Open
Abstract
Investigating cohesive tissue sheets in controlled cultures still poses a challenge since the complex intercellular interactions are difficult to mimic in in vitro models. We used supported lipid membranes functionalized by the adhesive part of the extracellular domain of the cell adhesion molecule cadherin-11 for the immobilization of pluripotent tissue sheets, the animal cap isolated from Xenopus laevis blastula stage embryos. Cadherin-11 was bound via histidine tag to lipid membranes with chelator head groups. In the first step, quantitative functionalization of the membranes with cadherin-11 was confirmed by quartz crystal microbalance and high energy specular X-ray reflectivity. In the next step, animal cap tissue sheets induced to neural crest cell fate were cultured on the membranes functionalized with cadherin-11. The adhesion of cells within the cohesive tissue was significantly dependent on changes in lateral densities of cadherin-11. The formation of filopodia and lamellipodia in the cohesive tissue verified the viability and sustainability of the culture over several hours. The expression of the transcription factor slug in externally induced tissue demonstrated the applicability of lipid membranes displaying adhesive molecules for controlled differentiation of cohesive pluripotent tissue sheets.
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Affiliation(s)
- Alexander Körner
- Physical Chemistry of Biosystems, Physical Chemistry Institute, University of Heidelberg, Heidelberg, Germany
| | - Christina Deichmann
- Cell and Developmental Biology, Zoological Institute, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Fernanda F. Rossetti
- Physical Chemistry of Biosystems, Physical Chemistry Institute, University of Heidelberg, Heidelberg, Germany
- * E-mail: (FFR); (DW)
| | - Almut Köhler
- Cell and Developmental Biology, Zoological Institute, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | | | - Doris Wedlich
- Cell and Developmental Biology, Zoological Institute, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
- * E-mail: (FFR); (DW)
| | - Motomu Tanaka
- Physical Chemistry of Biosystems, Physical Chemistry Institute, University of Heidelberg, Heidelberg, Germany
- Cell Biophysics Laboratory, Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
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20
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Bihr T, Seifert U, Smith AS. Nucleation of ligand-receptor domains in membrane adhesion. PHYSICAL REVIEW LETTERS 2012; 109:258101. [PMID: 23368503 DOI: 10.1103/physrevlett.109.258101] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Indexed: 06/01/2023]
Abstract
We present a comprehensive model for the nucleation of domains in membrane adhesion. We determine the critical number of bonds in a nucleus and calculate the probability distribution of nucleation time from a discrete master equation. The latter is characterized by only four effective rates, which account for cooperative effects between bonds. We validate our model by finding excellent agreement with extensive Langevin simulations. In the range of parameters typical for cell adhesion, we find the critical number of bonds to be small. Furthermore, we find a characteristic separation between the bonds at which nucleation is particularly fast, pointing to potential regulatory mechanisms that could be used to control the cell recognition processes.
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Affiliation(s)
- Timo Bihr
- II. Institut für Theoretische Physik, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany
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21
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Wang W, Wang S, Liu Q, Wu J, Tao N. Mapping single-cell-substrate interactions by surface plasmon resonance microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:13373-9. [PMID: 22920036 PMCID: PMC3660850 DOI: 10.1021/la301712h] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
We report the imaging of the cell-substrate adhesion of a single cell with subcellular spatial resolution. Osmotic pressure was introduced to provide a controllable mechanical stimulation to the cell attached to a substrate, and high-resolution surface plasmon resonance microscopy was used to map the response of the cell, from which local cell-substrate adhesion was determined. In addition to high spatial resolution, the approach is noninvasive and fast and allows for the continuous mapping of cell-substrate interactions and single-cell movements.
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Affiliation(s)
- Wei Wang
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
| | - Shaopeng Wang
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
| | - Qiang Liu
- Division of Neurology, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, AZ 85013, USA
| | - Jie Wu
- Division of Neurology, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, AZ 85013, USA
| | - Nongjian Tao
- Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, AZ 85287, USA
- Department of Electrical Engineering, Arizona State University, Tempe, AZ 85287, USA
- Corresponding authors:
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22
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Abstract
Tremendous progress has been made in recent years in understanding the working of the living cell, including its micro-anatomy, signalling networks, and regulation of genes. However, an understanding of cellular phenomena using fundamental laws starting from first principles is still very far away. Part of the reason is that a cell is an active and exquisitely complex system where every part is linked to the other. Thus, it is difficult or even impossible to design experiments that selectively and exclusively probe a chosen aspect of the cell. Various kinds of idealised systems and cell models have been used to circumvent this problem. An important example is a giant unilamellar vesicle (GUV, also called giant liposome), which provides a cell-sized confined volume to study biochemical reactions as well as self-assembly processes that occur on the membrane. The GUV membrane can be designed suitably to present selected, correctly-oriented cell-membrane proteins, whose mobility is confined to two dimensions. Here, we present recent advances in GUV design and the use of GUVs as cell models that enable quantitative testing leading to insight into the working of real cells. We briefly recapitulate important classical concepts in membrane biophysics emphasising the advantages and limitations of GUVs. We then present results obtained over the last decades using GUVs, choosing the formation of membrane domains and cell adhesion as examples for in-depth treatment. Insight into cell adhesion obtained using micro-interferometry is treated in detail. We conclude by summarising the open questions and possible future directions.
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Affiliation(s)
- Susanne F Fenz
- Leiden Institute of Physics: Physics of Life Processes, Leiden University, The Netherlands
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23
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'Run-and-tumble' or 'look-and-run'? A mechanical model to explore the behavior of a migrating amoeboid cell. J Theor Biol 2012; 306:15-31. [PMID: 22726805 DOI: 10.1016/j.jtbi.2012.03.041] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 02/21/2012] [Accepted: 03/23/2012] [Indexed: 11/20/2022]
Abstract
Single cell migration constitutes a fundamental phenomenon involved in many biological events. Amoeboid cells are single cell organisms that migrate in a cyclic manner like worms. In this paper, we propose a 3D finite element model of an amoeboid cell migrating over a 2D surface. In particular, we focus on the mechanical aspect of the problem. The cell is able to generate cyclic active deformations, such as protrusion and contraction, in any direction. The progression of the cell is governed by a tight synchronization between the adhesion forces, which are alternatively applied at the front and at the rear edges of the cell, and the protrusion-contraction phases of the cell body. Finally, two important aspects have been taken into account: (1) the external stimuli in response to which the cell migrates (e.g. need to feed, morphogenetic events, normal or abnormal environment cues), (2) the heterogeneity of the 2D substrate (e.g. obstacles, rugosity, slippy regions) for which two distinct approaches have been evaluated: the 'run-and-tumble' strategy and the 'look-and-run' strategy. Overall, the results show a good agreement with respect to the experimental observations and the data from the literature (e.g. velocity and strains). Therefore, the present model helps, on one hand, to better understand the intimate relationship between the deformation modes of a cell and the adhesion strength that is required by the cell to crawl over a substrate, and, on the other hand, to put in evidence the crucial role played by mechanics during the migration process.
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24
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Lam Hui K, Wang C, Grooman B, Wayt J, Upadhyaya A. Membrane dynamics correlate with formation of signaling clusters during cell spreading. Biophys J 2012; 102:1524-33. [PMID: 22500752 DOI: 10.1016/j.bpj.2012.02.015] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2011] [Revised: 01/31/2012] [Accepted: 02/08/2012] [Indexed: 10/28/2022] Open
Abstract
The morphology and duration of contacts between cells and adhesive surfaces play a key role in several biological processes, such as cell migration, cell differentiation, and the immune response. The interaction of receptors on the cell membrane with ligands on the adhesive surface leads to triggering of signaling pathways, which allow cytoskeletal rearrangement, and large-scale deformation of the cell membrane, which allows the cell to spread over the substrate. Despite numerous studies of cell spreading, the nanometer-scale dynamics of the membrane during formation of contacts, spreading, and initiation of signaling are not well understood. Using interference reflection microscopy, we study the kinetics of cell spreading at the micron scale, as well as the topography and fluctuations of the membrane at the nanometer scale during spreading of Jurkat T cells on antibody-coated substrates. We observed two modes of spreading, which were characterized by dramatic differences in membrane dynamics and topography. Formation of signaling clusters was closely related to the movement and morphology of the membrane in contact with the activating surface. Our results suggest that cell membrane morphology may be a critical constraint on signaling at the cell-substrate interface.
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Affiliation(s)
- King Lam Hui
- Department of Physics, University of Maryland, College Park, Maryland, USA
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25
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Lorenz B, de Cienfuegos LÁ, Oelkers M, Kriemen E, Brand C, Stephan M, Sunnick E, Yüksel D, Kalsani V, Kumar K, Werz DB, Janshoff A. Model system for cell adhesion mediated by weak carbohydrate-carbohydrate interactions. J Am Chem Soc 2012; 134:3326-9. [PMID: 22296574 PMCID: PMC3288207 DOI: 10.1021/ja210304j] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The multivalent carbohydrate-carbohydrate interaction between membrane-anchored epitopes derived from the marine sponge Microciona prolifera has been explored by colloidal probe microscopy. An in situ coupling of sulfated and non-sulfated disaccharides to membrane-coated surfaces was employed to mimic native cell-cell contacts.The dynamic strength of the homomeric self-association was measured as a function of calcium ions and loading rate. A deterministic model was used to estimate the basic energy landscape and number of participating bonds in the contact zone.
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Affiliation(s)
- Bärbel Lorenz
- Institute of Physical Chemistry, University of Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
| | | | - Marieelen Oelkers
- Institute of Physical Chemistry, University of Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
| | - Ella Kriemen
- Institute of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstr. 2, 37077 Göttingen, Germany
| | - Christian Brand
- Institute of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstr. 2, 37077 Göttingen, Germany
| | - Milena Stephan
- Institute of Physical Chemistry, University of Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
| | - Eva Sunnick
- Institute of Physical Chemistry, University of Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
| | - Deniz Yüksel
- Department of Chemistry, Pearson Chemistry Laboratory, 62 Talbot Avenue, Tufts University, 62 Talbot Avenue, Medford, MA 02155
| | - Venkateshwarlu Kalsani
- Department of Chemistry, Pearson Chemistry Laboratory, 62 Talbot Avenue, Tufts University, 62 Talbot Avenue, Medford, MA 02155
| | - Krishna Kumar
- Department of Chemistry, Pearson Chemistry Laboratory, 62 Talbot Avenue, Tufts University, 62 Talbot Avenue, Medford, MA 02155
| | - Daniel B Werz
- Institute of Organic and Biomolecular Chemistry, University of Göttingen, Tammannstr. 2, 37077 Göttingen, Germany
| | - Andreas Janshoff
- Institute of Physical Chemistry, University of Göttingen, Tammannstr. 6, 37077 Göttingen, Germany
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26
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Gongadze E, van Rienen U, Kralj-Iglič V, Iglič A. Spatial variation of permittivity of an electrolyte solution in contact with a charged metal surface: a mini review. Comput Methods Biomech Biomed Engin 2012; 16:463-80. [PMID: 22263808 PMCID: PMC3664910 DOI: 10.1080/10255842.2011.624769] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Revised: 09/14/2011] [Indexed: 11/14/2022]
Abstract
Contact between a charged metal surface and an electrolyte implies a particular ion distribution near the charged surface, i.e. the electrical double layer. In this mini review, different mean-field models of relative (effective) permittivity are described within a simple lattice model, where the orientational ordering of water dipoles in the saturation regime is taken into account. The Langevin-Poisson-Boltzmann (LPB) model of spatial variation of the relative permittivity for point-like ions is described and compared to a more general Langevin-Bikerman (LB) model of spatial variation of permittivity for finite-sized ions. The Bikerman model and the Poisson-Boltzmann model are derived as limiting cases. It is shown that near the charged surface, the relative permittivity decreases due to depletion of water molecules (volume-excluded effect) and orientational ordering of water dipoles (saturation effect). At the end, the LPB and LB models are generalised by also taking into account the cavity field.
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Affiliation(s)
- E. Gongadze
- Laboratory of Biophysics, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
| | - U. van Rienen
- Faculty of Computer Science and Electrical Engineering, University of Rostock, Rostock, Germany
| | - V. Kralj-Iglič
- Laboratory of Clinical Biophysics, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia
| | - A. Iglič
- Laboratory of Biophysics, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia
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27
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Jiang H, Yang B. Cell-substrate interaction with cell-membrane-stress dependent adhesion. J Biomech 2012; 45:209-17. [PMID: 22119548 DOI: 10.1016/j.jbiomech.2011.11.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 11/04/2011] [Accepted: 11/05/2011] [Indexed: 01/09/2023]
Abstract
Cell-substrate interaction is examined in a two-dimensional mechanics model. The cell and substrate are treated as a shell and an elastic solid, respectively. Their interaction through adhesion is treated using nonlinear springs. Compared to previous cell mechanics models, the present model introduces a cohesive force law that is dependent not only on cell-substrate distance but also on internal cell-membrane stress. It is postulated that a living cell would establish focal adhesion sites with density dependent on the cell-membrane stress. The formulated mechanics problem is numerically solved using coupled finite elements and boundary elements for the cell and the substrate, respectively. The nodes in the adhesion zone from either side are linked by the cohesive springs. The specific cases of a cell adhering to a homogeneous substrate and a heterogeneous bimaterial substrate are examined. The analyses show that the substrate stiffness affects the adhesion behavior significantly and regulates the direction of cell adhesion, in good agreement with the experimental results in the literature. By introducing a reactive parameter (i.e., cell-membrane stress) linking biological responses of a living cell to a mechanical environment, the present model offers a unified mechanistic vehicle for characterization and prediction of living cell responses to various kinds of mechanical stimuli including local extracellular matrix and neighboring cells.
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Affiliation(s)
- H Jiang
- Department of Mechanical and Aerospace Engineering, Florida Institute of Technology, Melbourne, FL 32901, USA.
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28
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Feracci H, Gutierrez BS, Hempel W, Gil IS. Organic Nanoparticles. NANOBIOTECHNOLOGY - INORGANIC NANOPARTICLES VS ORGANIC NANOPARTICLES 2012. [DOI: 10.1016/b978-0-12-415769-9.00008-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
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29
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Sanz-Herrera JA, Reina-Romo E. Cell-biomaterial mechanical interaction in the framework of tissue engineering: insights, computational modeling and perspectives. Int J Mol Sci 2011; 12:8217-44. [PMID: 22174660 PMCID: PMC3233466 DOI: 10.3390/ijms12118217] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2011] [Revised: 10/19/2011] [Accepted: 11/02/2011] [Indexed: 01/09/2023] Open
Abstract
Tissue engineering is an emerging field of research which combines the use of cell-seeded biomaterials both in vitro and/or in vivo with the aim of promoting new tissue formation or regeneration. In this context, how cells colonize and interact with the biomaterial is critical in order to get a functional tissue engineering product. Cell-biomaterial interaction is referred to here as the phenomenon involved in adherent cells attachment to the biomaterial surface, and their related cell functions such as growth, differentiation, migration or apoptosis. This process is inherently complex in nature involving many physico-chemical events which take place at different scales ranging from molecular to cell body (organelle) levels. Moreover, it has been demonstrated that the mechanical environment at the cell-biomaterial location may play an important role in the subsequent cell function, which remains to be elucidated. In this paper, the state-of-the-art research in the physics and mechanics of cell-biomaterial interaction is reviewed with an emphasis on focal adhesions. The paper is focused on the different models developed at different scales available to simulate certain features of cell-biomaterial interaction. A proper understanding of cell-biomaterial interaction, as well as the development of predictive models in this sense, may add some light in tissue engineering and regenerative medicine fields.
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Affiliation(s)
- Jose A. Sanz-Herrera
- School of Engineering, University of Seville, Camino de los descubrimientos s/n, 41092 Seville, Spain; E-Mail:
| | - Esther Reina-Romo
- School of Engineering, University of Seville, Camino de los descubrimientos s/n, 41092 Seville, Spain; E-Mail:
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Nam J, Santore MM. Depletion versus deflection: how membrane bending can influence adhesion. PHYSICAL REVIEW LETTERS 2011; 107:078101. [PMID: 21902431 DOI: 10.1103/physrevlett.107.078101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Revised: 04/15/2011] [Indexed: 05/31/2023]
Abstract
During depletion-driven vesicle adhesion, a stiff membrane's resistance to bending at fixed tension prevents contact angle equilibrium and vesicle spreading over an opposing vesicle, while more flexible vesicles partially engulf opposing vesicles. Estimates of the bending cost associated with the spreading contact line, relative to the adhesion energy, were consistent with the observed spreading or lack of spreading for the flexible and stiff membranes, respectively, and predicted a lag time sometimes preceding spreading.
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Affiliation(s)
- Jin Nam
- Department of Polymer Science and Engineering, University of Massachusetts, Amherst, 01003, USA
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31
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Atılgan E, Ovryn B. Reflectivity and topography of cells grown on glass-coverslips measured with phase-shifted laser feedback interference microscopy. BIOMEDICAL OPTICS EXPRESS 2011; 2:2417-2437. [PMID: 21833378 PMCID: PMC3149539 DOI: 10.1364/boe.2.002417] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 07/05/2011] [Accepted: 07/15/2011] [Indexed: 05/31/2023]
Abstract
In spite of the advantages associated with the molecular specificity of fluorescence imaging, there is still a significant need to augment these approaches with label-free imaging. Therefore, we have implemented a form of interference microscopy based upon phase-shifted, laser-feedback interferometry and developed an algorithm that can be used to separate the contribution of the elastically scattered light by sub-cellular structures from the reflection at the coverslip-buffer interface. The method offers an opportunity to probe protein aggregation, index of refraction variations and structure. We measure the topography and reflection from calibration spheres and from stress fibers and adhesions in both fixed and motile cells. Unlike the data acquired with reflection interference contrast microscopy, where the reflection from adhesions can appear dark, our approach demonstrates that these regions have high reflectivity. The data acquired from fixed and live cells show the presence of a dense actin layer located ≈ 100 nm above the coverslip interface. Finally, the measured dynamics of filopodia and the lamella in a live cell supports retrograde flow as the dominate mechanism responsible for filopodia retraction.
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Affiliation(s)
- Erdinç Atılgan
- Department of Anatomy and Structural Biology, Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York,
USA
| | - Ben Ovryn
- Department of Anatomy and Structural Biology, Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, New York,
USA
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32
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Wheeldon I, Farhadi A, Bick AG, Jabbari E, Khademhosseini A. Nanoscale tissue engineering: spatial control over cell-materials interactions. NANOTECHNOLOGY 2011; 22:212001. [PMID: 21451238 PMCID: PMC3155808 DOI: 10.1088/0957-4484/22/21/212001] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Cells interact with the surrounding environment by making tens to hundreds of thousands of nanoscale interactions with extracellular signals and features. The goal of nanoscale tissue engineering is to harness these interactions through nanoscale biomaterials engineering in order to study and direct cellular behavior. Here, we review two- and three-dimensional (2- and 3D) nanoscale tissue engineering technologies, and provide a holistic overview of the field. Techniques that can control the average spacing and clustering of cell adhesion ligands are well established and have been highly successful in describing cell adhesion and migration in 2D. Extension of these engineering tools to 3D biomaterials has created many new hydrogel and nanofiber scaffold technologies that are being used to design in vitro experiments with more physiologically relevant conditions. Researchers are beginning to study complex cell functions in 3D. However, there is a need for biomaterials systems that provide fine control over the nanoscale presentation of bioactive ligands in 3D. Additionally, there is a need for 2- and 3D techniques that can control the nanoscale presentation of multiple bioactive ligands and that can control the temporal changes in the cellular microenvironment.
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Affiliation(s)
- Ian Wheeldon
- Department of Medicine, Center for Biomedical Engineering, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Arash Farhadi
- Department of Medicine, Center for Biomedical Engineering, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Nanotechnology Engineering Program, University of Waterloo, Waterloo, ON, N2L 3G1 Canada
| | - Alexander G. Bick
- Department of Medicine, Center for Biomedical Engineering, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Esmaiel Jabbari
- Department of Chemical Engineering, University of South Carolina, Columbia, SC, 29208
| | - Ali Khademhosseini
- Department of Medicine, Center for Biomedical Engineering, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
- Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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33
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Wiederhorn SM, Chae YH, Simon CG, Cahn J, Deng Y, Day D. Cell adhesion to borate glasses by colloidal probe microscopy. Acta Biomater 2011; 7:2256-63. [PMID: 21241832 DOI: 10.1016/j.actbio.2011.01.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2010] [Revised: 12/30/2010] [Accepted: 01/12/2011] [Indexed: 11/30/2022]
Abstract
The adhesion of osteoblast-like cells to silicate and borate glasses was measured in cell growth medium using colloidal probe microscopy. The probes consisted of silicate and borate glass spheres, 25-50 μm in diameter, attached to atomic force microscope cantilevers. Variables of the study included glass composition and time of contact of the cell to the glasses. Increasing the time of contact from 15 to 900 s increased the force of adhesion. The data could be plotted linearly on a log-log plot of adhesive force versus time. Of the seven glasses tested, five had slopes close to 0.5, suggesting a square root dependence of the adhesive force on the contact time. Such behavior can be interpreted as a diffusion limited process occurring during the early stages of cell attachment. We suggest that the rate limiting step in the adhesion process is the diffusion of integrins resident in the cell membrane to the area of cell attachment. Data presented in this paper support the hypothesis of Hench et al. that strong adhesion depends on the formation of a calcium phosphate reaction layer on the surfaces of the glass. Glasses that did not form a calcium phosphate layer exhibited a weaker adhesive force relative to those glasses that did form a calcium phosphate layer.
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Affiliation(s)
- Sheldon M Wiederhorn
- Ceramics Division/Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, MD, USA.
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Abstract
AbstractA mathematical model describing how a cell membrane with diffusive mobile receptors wraps around a ligand coated cylindrical or spherical particle has been recently developed to model particle size effects in receptor mediated endocytosis. The model predicted an optimal particle size for the smallest wrapping time, as well as a minimum and a maximum particle size for successful wrapping. The results showed that particles in the size range of tens to hundreds of nanometers can enter cells even in the absence of clathrin or caveolin coats. Here we report some further progresses on modeling a spontaneous membrane curvature induced by clathrin or caveolin coats at the inner membrane leaflet as well as simultaneous entry of many particles into cells. It is found that a spontaneous membrane curvature narrows the particle size range for successful wrapping and there exists an optimal particle density for maximum particle adsorptivity.
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TABER L, SHI Y, YANG L, BAYLY P. A POROELASTIC MODEL FOR CELL CRAWLING INCLUDING MECHANICAL COUPLING BETWEEN CYTOSKELETAL CONTRACTION AND ACTIN POLYMERIZATION. JOURNAL OF MECHANICS OF MATERIALS AND STRUCTURES 2011; 6:569-589. [PMID: 21765817 PMCID: PMC3134831 DOI: 10.2140/jomms.2011.6.569] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Much is known about the biophysical mechanisms involved in cell crawling, but how these processes are coordinated to produce directed motion is not well understood. Here, we propose a new hypothesis whereby local cytoskeletal contraction generates fluid flow through the lamellipodium, with the pressure at the front of the cell facilitating actin polymerization which pushes the leading edge forward. The contraction, in turn, is regulated by stress in the cytoskeleton. To test this hypothesis, finite element models for a crawling cell are presented. These models are based on nonlinear poroelasticity theory, modified to include the effects of active contraction and growth, which are regulated by mechanical feedback laws. Results from the models agree reasonably well with published experimental data for cell speed, actin flow, and cytoskeletal deformation in migrating fish epidermal keratocytes. The models also suggest that oscillations can occur for certain ranges of parameter values.
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Affiliation(s)
- L.A. TABER
- Department of Biomedical Engineering, 1 Brookings Drive, Box 1097, Washington University, St. Louis, MO 63130, USA
| | - Y. SHI
- Department of Biomedical Engineering, Washington University, 1 Brookings Drive, Box 1097, St. Louis, MO 63130, USA
| | - L. YANG
- Department of Biomedical Engineering, Washington University, 1 Brookings Drive, Box 1097, St. Louis, MO 63130, USA
| | - P.V. BAYLY
- Department of Mechanical Engineering and Materials Science, Washington University, 1 Brookings Drive, Box 1185, St. Louis, MO 63130, USA
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36
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Kalasin S, Martwiset S, Coughlin EB, Santore MM. Particle capture via discrete binding elements: systematic variations in binding energy for randomly distributed nanoscale surface features. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:16865-16870. [PMID: 20961162 DOI: 10.1021/la103023t] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This work examines how the binding strength of surface-immobilized "stickers" (representative of receptors or, in nonbiological systems, chemical heterogeneities) influences the adhesion between surfaces that are otherwise repulsive. The study focuses on a series of surfaces designed with fixed average adhesive energy per unit area and demonstrates quantitatively how a redistribution of the adhesive functionality into progressively larger clusters (stronger stickers) increases the probability of adhesive events. The work employs an electrostatic model system: relatively uniform, negative 1 μm silica spheres flow gently over negative silica flats. The flats contain small amounts of randomly positioned nanoscale cationic patches. The silica-silica interaction is repulsive; however, the cationic patches (present at sufficiently low levels that the overall surface charge remains substantially negative) produce local attractions. In this study, the attractions are relatively weak so that multiple patches engage to capture flowing particles. Experiments reveal an adhesion signature characteristic of a renormalized random distribution when the sticker strength is increased at an overall fixed binding strength per unit area of surface. The form of the particle capture curves are in good quantitative agreement with a simple model that assumes only a fixed adhesion energy needed for particle capture. Aside from the quantitative details that provide a simple formalism for anticipating particle adhesion, this work demonstrates how increasing the heterogeneities in the surface functionality can cause a system to go from being nonadhesive to becoming strongly adhesive. Indeed, systems containing small amounts of discretized adhesive functionality are always more adhesive than systems in which the same functionality is distributed uniformly over the surface (the mean field scenario).
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Affiliation(s)
- Surachate Kalasin
- Department of Polymer Science and Engineering, University of Massachusetts, 120 Governor's Drive, Amherst, Massachusetts 01003, United States
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37
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Raudino A, Pannuzzo M. Adhesion Kinetics between a Membrane and a Flat Substrate. An Ideal Upper Bound to the Spreading Rate of an Adhesive Patch. J Phys Chem B 2010; 114:15495-505. [DOI: 10.1021/jp106722w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Antonio Raudino
- Dipartimento di Scienze Chimiche, Università di Catania, Viale A. Doria 6-95125, Catania, Italy
| | - Martina Pannuzzo
- Dipartimento di Scienze Chimiche, Università di Catania, Viale A. Doria 6-95125, Catania, Italy
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38
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Compliance of bio-adhesive substrates controls the kinetics of membrane-substrate association. J Theor Biol 2010; 266:516-21. [PMID: 20655930 DOI: 10.1016/j.jtbi.2010.07.021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2010] [Revised: 06/23/2010] [Accepted: 07/21/2010] [Indexed: 11/23/2022]
Abstract
Mechanical stiffness of bio-adhesive substrates is one of the major regulators of the cell adhesion and migration. In this study, we propose a theoretical model for the spontaneous growth of focal adhesion (FA) sites, on compliant elastic substrates, at the early stages of cellular adhesion. Using a purely thermodynamic approach, we demonstrate that the rate of membrane-substrate association decreases with increasing the compliance of the substrate. This can be considered as a reason for smaller spread area of the FA points after the stabilization of adhesion on compliant substrates, as reported by experiments. We also show that the extent to which the compliance of the substrate modulates the growth rate of adhesion site depends on the areal density of cell-adhesive ligands on the substrate.
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39
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Sengupta K, Limozin L. Adhesion of soft membranes controlled by tension and interfacial polymers. PHYSICAL REVIEW LETTERS 2010; 104:088101. [PMID: 20366967 DOI: 10.1103/physrevlett.104.088101] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2009] [Indexed: 05/29/2023]
Abstract
We examine experimental and theoretical aspects of nonspecific adhesion of giant vesicles on modified surfaces as model systems for cell spreading. Using dual-wave interference microscopy and new analysis, membrane undulations as well as large scale vesicle shape are monitored. Measurements and modelling show that the nucleation of adhesion depends critically on the interfacial polymer and membrane tension. Patch growth is governed by local membrane geometry, adhesion energy, and local viscosity. Finally, spreading stops when tension induced by adhesion unfolds excess membrane area.
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Affiliation(s)
- Kheya Sengupta
- CNRS, Aix-Marseille University, CINaM-UPR3118, Campus Luminy, Case 913 F-13288, Marseille, France
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40
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Limozin L, Sengupta K. Quantitative reflection interference contrast microscopy (RICM) in soft matter and cell adhesion. Chemphyschem 2010; 10:2752-68. [PMID: 19816893 DOI: 10.1002/cphc.200900601] [Citation(s) in RCA: 146] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Adhesion can be quantified by measuring the distance between the interacting surfaces. Reflection interference contrast microscopy (RICM), with its ability to measure inter-surface distances under water with nanometric precision and milliseconds time resolution, is ideally suited to studying the dynamics of adhesion in soft systems. Recent technical developments, which include innovative image analysis and the use of multi-coloured illumination, have led to renewed interest in this technique. Unambiguous quantitative measurements have been achieved for colloidal beads and model membranes, thus revealing new insights and applications. Quantification of data from cells shows exciting prospects. Herein, we review the basic principles and recent developments of RICM applied to studies of dynamical adhesion processes in soft matter and cell biology and provide practical hints to potential users.
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Affiliation(s)
- Laurent Limozin
- Adhesion and Inflammation, CNRS UMR 6212, Inserm U600, Aix-Marseille University, Luminy, Marseille, France.
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41
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Raudino A, Pannuzzo M. Nucleation theory with delayed interactions: An application to the early stages of the receptor-mediated adhesion/fusion kinetics of lipid vesicles. J Chem Phys 2010; 132:045103. [DOI: 10.1063/1.3290823] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
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42
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Liu P, Zhang YW, Yu H, Zhang X, Cheng QH, Lu C, Bonfield W. Spreading of an anchorage-dependent cell on a selectively ligand-coated substrate mediated by receptor-ligand binding. J Biomed Mater Res A 2009; 91:806-13. [DOI: 10.1002/jbm.a.32258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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43
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Streicher P, Nassoy P, Bärmann M, Dif A, Marchi-Artzner V, Brochard-Wyart F, Spatz J, Bassereau P. Integrin reconstituted in GUVs: a biomimetic system to study initial steps of cell spreading. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2009; 1788:2291-300. [PMID: 19665445 DOI: 10.1016/j.bbamem.2009.07.025] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2009] [Revised: 07/10/2009] [Accepted: 07/27/2009] [Indexed: 10/20/2022]
Abstract
A novel in vitro membrane system mimicking the first steps of integrin-mediated cell spreading has been developed and characterized. We have reconstituted the transmembrane alpha(IIb)beta(3) integrin into giant unilamellar vesicles (GUVs). The reconstitution process has been validated by analyzing protein incorporation and biological activity by checking the specific interaction of GUVs containing integrin with quantum dots (QD) or surfaces coated with the integrin receptor tri-peptide RGD.(1) The spreading dynamics of integrin-functionalized GUVs onto fibrinogen-coated surfaces has been monitored by Reflection Interference Contrast Microscopy (RICM). Our results are quantitatively consistent with a theoretical model based on a dewetting process coupled to binder diffusion and provide a comprehensive description of the following sequence: i) nucleation and growth of adhesive patches coupled to the diffusion of the adhesive proteins to these adhesive zones ii) fusion of patches and formation of an adhesive ring iii) complete spreading of the GUV by dewetting of the central liquid film from the border to form an adhesive circular patch that is not significantly enriched in integrins, as compared to the unbound membrane. This finding is consistent with the recognized role of the actin cytoskeleton in stabilizing focal complexes and focal adhesions in a cell-extracellular matrix contact. These very large unilamellar integrin-containing vesicles provide a unique artificial system, which could be further developed towards realistic cell mimic and used to study the complexity of integrin-mediated cell spreading.
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Affiliation(s)
- Pia Streicher
- Institut Curie, Centre de Recherche, Université Pierre et Marie Curie, F-75248 Paris, France
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44
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Warner JM, Karatekin E, O'Shaughnessy B. Model of SNARE-mediated membrane adhesion kinetics. PLoS One 2009; 4:e6375. [PMID: 19649266 PMCID: PMC2715897 DOI: 10.1371/journal.pone.0006375] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Accepted: 06/10/2009] [Indexed: 01/16/2023] Open
Abstract
SNARE proteins are conserved components of the core fusion machinery driving diverse membrane adhesion and fusion processes in the cell. In many cases micron-sized membranes adhere over large areas before fusion. Reconstituted in vitro assays have helped isolate SNARE mechanisms in small membrane adhesion-fusion and are emerging as powerful tools to study large membrane systems by use of giant unilamellar vesicles (GUVs). Here we model SNARE-mediated adhesion kinetics in SNARE-reconstituted GUV-GUV or GUV-supported bilayer experiments. Adhesion involves many SNAREs whose complexation pulls apposing membranes into contact. The contact region is a tightly bound rapidly expanding patch whose growth velocity v(patch) increases with SNARE density Gamma(snare). We find three patch expansion regimes: slow, intermediate, fast. Typical experiments belong to the fast regime where v(patch) ~ (Gamma(snare)(2/3) depends on SNARE diffusivities and complexation binding constant. The model predicts growth velocities ~10 - 300 microm/s. The patch may provide a close contact region where SNAREs can trigger fusion. Extending the model to a simple description of fusion, a broad distribution of fusion times is predicted. Increasing SNARE density accelerates fusion by boosting the patch growth velocity, thereby providing more complexes to participate in fusion. This quantifies the notion of SNAREs as dual adhesion-fusion agents.
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Affiliation(s)
- Jason M. Warner
- Jason M. Warner, Department of Chemical Engineering, Columbia University, New York, New York, United States of America
| | - Erdem Karatekin
- Erdem Karatekin, Institut de Biologie Physico-Chimique, Centre National de la Recherche Scientifique UPR 1929, Paris, France
| | - Ben O'Shaughnessy
- Ben O'Shaughnessy, Department of Chemical Engineering, Columbia University, New York, New York, United States of America
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45
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Nucleation and growth of integrin adhesions. Biophys J 2009; 96:3555-72. [PMID: 19413961 DOI: 10.1016/j.bpj.2009.02.023] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 01/28/2009] [Accepted: 02/02/2009] [Indexed: 01/09/2023] Open
Abstract
We present a model that provides a mechanistic understanding of the processes that govern the formation of the earliest integrin adhesions ex novo from an approximately planar plasma membrane. Using an analytic analysis of the free energy of a dynamically deformable membrane containing freely diffusing receptors molecules and long repeller molecules that inhibit integrins from binding with ligands on the extracellular matrix, we predict that a coalescence of polymerizing actin filaments can deform the membrane toward the extracellular matrix and facilitate integrin binding. Monte Carlo simulations of this system show that thermally induced membrane fluctuations can either zip-up and increase the radius of a nucleated adhesion or unzip and shrink an adhesion, but the fluctuations cannot bend the ventral membrane to nucleate an adhesion. To distinguish this integrin adhesion from more mature adhesions, we refer to this early adhesion as a nouveau adhesion.
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46
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Quantification of nano-scale intermembrane contact areas by using fluorescence resonance energy transfer. Proc Natl Acad Sci U S A 2009; 106:12341-6. [PMID: 19597158 DOI: 10.1073/pnas.0903052106] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Nanometer-scale intermembrane contact areas (CAs) formed between single small unilamellar lipid vesicles (SUVs) and planar supported lipid bilayers are quantified by measuring fluorescence resonance energy transfer (FRET) between a homogenous layer of donor fluorophores labeling the supported bilayer and acceptor fluorophores labeling the SUVs. The smallest CAs detected in our setup between biotinylated SUVs and dense monolayers of streptavidin were approximately 20 nm in radius. Deformation of SUVs is revealed by comparing the quenching of the donors to calculations of FRET between a perfectly spherical shell and a flat surface containing complementary fluorophores. These results confirmed the theoretical prediction that the degree of deformation scales with the SUV diameter. The size of the CA can be controlled experimentally by conjugating polyethylene glycol polymers to the SUV or the surface and thereby modulating the interfacial energy of adhesion. In this manner, we could achieve secure immobilization of SUVs under conditions of minimal deformation. Finally, we demonstrate that kinetic measurements of CA, at constant adhesion, can be used to record in real-time quantitative changes in the bilayer tension of a nano-scale lipid membrane system.
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47
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Xu GK, Feng XQ, Zhao HP, Li B. Theoretical study of the competition between cell-cell and cell-matrix adhesions. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:011921. [PMID: 19658743 DOI: 10.1103/physreve.80.011921] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2008] [Revised: 05/20/2009] [Indexed: 05/28/2023]
Abstract
Adhesions between neighboring cells or between cells and their surrounding tissue/matrix play a crucial role in a wide range of biological processes. In order to investigate the competitive mechanisms between cell-cell and cell-matrix adhesions, we here develop a theoretical framework for multiple interacting cells lying on a planar matrix coated with distributed ligands. This model allows us to study, from the viewpoints of energy and statistics, the effects of such physical mechanisms as binding energy of bonds, nonspecific interactions, elastic deformation of cell membranes, and mixing entropy. Our calculations show that cell-matrix adhesion cannot occur when the ligand density on the matrix is lower than a threshold value, and cell-cell adhesion does not happen for a high ligand density. Glycocalyx repulsion plays a more important role in cell-matrix adhesion than in cell-cell adhesion. In addition, it is found that the cell-cell adhesion density decreases as the number of cells increases.
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Affiliation(s)
- Guang-Kui Xu
- Department of Engineering Mechanics, Institute of Biomechanics and Medical Engineering, AML, Tsinghua University, Beijing 100084, China
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48
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Sun L, Cheng QH, Gao HJ, Zhang YW. Computational modeling for cell spreading on a substrate mediated by specific interactions, long-range recruiting interactions, and diffusion of binders. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:061907. [PMID: 19658524 DOI: 10.1103/physreve.79.061907] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2008] [Revised: 04/28/2009] [Indexed: 05/28/2023]
Abstract
A continuum model was proposed to study cell spreading on a flat substrate mediated by specific interaction, long-range recruiting interaction, and the diffusion of binders. Specific interactions between the mobile receptors embedded in the cell membrane and ligands coated on the substrate surface result in cell adhesion to the substrate surface. This receptor-ligand interaction was described by a chemical reaction equation. Long-range recruiting interactions between the receptors and the substrate were simplified by a traction-separation law. The governing equations and boundary conditions were formulated for the entire process of cell spreading and solved using a finite element scheme. Parametric studies were conducted to investigate the effect of system parameters on the cell spreading kinetics. It is shown that kinetic factors play an important role in cell adhesion and three regimes, that is, the binder reaction limited regime, long-range recruiting force-driven binder recruitment limited regime, and the concentration gradient-driven diffusion limited regime, were identified.
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Affiliation(s)
- Lu Sun
- Department of Materials Science and Engineering, National University of Singapore, Singapore 119260, Singapore
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Smith AS, Sackmann E. Progress in mimetic studies of cell adhesion and the mechanosensing. Chemphyschem 2009; 10:66-78. [PMID: 19115325 DOI: 10.1002/cphc.200800683] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Vesicle-substrate adhesion has been studied for over two decades with the motivation to understand and mimic cell adhesion. In recent years, with progress in theoretical modelling, the development of experimental techniques, and improved data-analysis procedures, considerable advances have been made in the understanding of the adhesion process. It is this progress which constitutes the focus of this review.
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Affiliation(s)
- Ana-Suncana Smith
- II. Institut für theoretische Physik, Universität Stuttgart, Pfaffenwaldring 57/III, Stuttgart,D-70550, Germany.
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Reister-Gottfried E, Sengupta K, Lorz B, Sackmann E, Seifert U, Smith AS. Dynamics of specific vesicle-substrate adhesion: from local events to global dynamics. PHYSICAL REVIEW LETTERS 2008; 101:208103. [PMID: 19113383 DOI: 10.1103/physrevlett.101.208103] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Indexed: 05/27/2023]
Abstract
We present a synergistic combination of simulations and experimental data on the dynamics of membrane adhesion. We show that a change in either the density or the strength of the bonds results in very different dynamics. Such behavior is explained by introducing an effective binding affinity that emerges as a result of the competition between the strength of the chemical bonds and the environment defined by the fluctuating membrane.
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