1
|
Sakakibara S, Abdellatef SA, Yamamoto S, Kamimura M, Nakanishi J. Photoactivatable surfaces resolve the impact of gravity vector on collective cell migratory characteristics. SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS 2023; 24:2206525. [PMID: 37151805 PMCID: PMC10158565 DOI: 10.1080/14686996.2023.2206525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Despite considerable interest in the impact of space travel on human health, the influence of the gravity vector on collective cell migration remains unclear. This is primarily because of the difficulty in inducing collective migration, where cell clusters appear in an inverted position against gravity, without cellular damage. In this study, photoactivatable surfaces were used to overcome this challenge. Photoactivatable surfaces enable the formation of geometry-controlled cellular clusters and the remote induction of cellular migration via photoirradiation, thereby maintaining the cells in the inverted position. Substrate inversion preserved the circularity of cellular clusters compared to cells in the normal upright position, with less leader cell appearance. Furthermore, the inversion of cells against the gravity vector resulted in the remodeling of the cytoskeletal system via the strengthening of external actin bundles. Within the 3D cluster architecture, enhanced accumulation of active myosin was observed in the upper cell-cell junction, with a flattened apical surface. Depending on the gravity vector, attenuating actomyosin activity correlates with an increase in the number of leader cells, indicating the importance of cell contractility in collective migration phenotypes and cytoskeletal remodeling.
Collapse
Affiliation(s)
- Shinya Sakakibara
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan
- Graduate School of Advanced Engineering, Tokyo University of Science, Tokyo, Japan
| | - Shimaa A. Abdellatef
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan
- CONTACT Shimaa A. Abdellatef
| | - Shota Yamamoto
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan
| | - Masao Kamimura
- Graduate School of Advanced Engineering, Tokyo University of Science, Tokyo, Japan
| | - Jun Nakanishi
- Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), Tsukuba, Japan
- Graduate School of Advanced Engineering, Tokyo University of Science, Tokyo, Japan
- Graduate school of Advanced Science and Engineering, Waseda University, Tokyo, Japan
- Jun Nakanishi Research Center for Macromolecules and Biomaterials, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba305-0044, Japan
| |
Collapse
|
2
|
Nakanishi J, Yamamoto S. Static and photoresponsive dynamic materials to dissect physical regulation of cellular functions. Biomater Sci 2022; 10:6116-6134. [PMID: 36111810 DOI: 10.1039/d2bm00789d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Recent progress in mechanobiology has highlighted the importance of physical cues, such as mechanics, geometry (size), topography, and porosity, in the determination of cellular activities and fates, in addition to biochemical factors derived from their surroundings. In this review, we will first provide an overview of how such fundamental insights are identified by synchronizing the hierarchical nature of biological systems and static materials with tunable physical cues. Thereafter, we will explain the photoresponsive dynamic biomaterials to dissect the spatiotemporal aspects of the dependence of biological functions on physical cues.
Collapse
Affiliation(s)
- Jun Nakanishi
- Research Center for Functional Materials, National Institute for Materials Science, Japan. .,Graduate School of Advanced Science and Engineering, Waseda University, Japan.,Graduate School of Advanced Engineering, Tokyo University of Science, Japan
| | - Shota Yamamoto
- Research Center for Functional Materials, National Institute for Materials Science, Japan. .,Graduate School of Arts and Sciences, The University of Tokyo, Japan
| |
Collapse
|
3
|
Bugga P, Mrksich M. Sequential Photoactivation of Self-Assembled Monolayers to Direct Cell Adhesion and Migration. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:5937-5943. [PMID: 30943037 PMCID: PMC8262134 DOI: 10.1021/acs.langmuir.8b04203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Dynamic substrates for cell culture control the spatial and temporal presentation of extracellular matrix ligands that interact with adherent cells. This paper reports a photoactive surface chemistry that can repeatedly activate regions of the substrate for cell adhesion, spreading, and migration. The approach uses self-assembled monolayers presenting the integrin ligand RGD that is caged with a nitrophenyl-based photoprotecting group. The group is also modified with a maltoheptaose oligosaccharide to prevent nonspecific protein adsorption and cell attachment. The peptide is uncaged when irradiated with a laser source at 405 nm on a microscope to reveal micron-size regions for single cell attachment. This method is applied to studies of gap junction-mediated communication between two neighboring cells and requires the patterning of an initial receiver cell population and then the patterning of a second sender population to give a culture wherein each pair of cells are separated by 30 μm. Finally, activation of the region between the cells permits cell-cell contact and gap junction assembly between the sender and receiver cells. This example demonstrates the broad relevance of this method to studying complex phenotypes in cell culture.
Collapse
Affiliation(s)
- Pradeep Bugga
- Department of Chemistry, Department of Biomedical Engineering, and Department of Cell and Molecular Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Milan Mrksich
- Department of Chemistry, Department of Biomedical Engineering, and Department of Cell and Molecular Biology, Northwestern University, Evanston, Illinois 60208, United States
| |
Collapse
|
4
|
Yamamoto S, Ikegami H, Yamaguchi K, Nakanishi J. A Dynamic Biomaterial Based on a 2-Nitrobenzyl Derivative with a tert
-Butyl Substituent at the Benzyl Position: Rapid Response and Minimized Phototoxicity. CHEMPHOTOCHEM 2018. [DOI: 10.1002/cptc.201800087] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Shota Yamamoto
- International Center for Materials Nanoarchitectonics (WPI-MANA); National Institute for Materials Science (NIMS); 1-1 Namiki, Tsukuba Ibaraki 305-0044 Japan
| | - Hiroki Ikegami
- Department of Chemistry; Kanagawa University; 2946 Tsuchiya, Hiratsuka Kanagawa 259-1293 Japan
| | - Kazuo Yamaguchi
- Department of Chemistry; Kanagawa University; 2946 Tsuchiya, Hiratsuka Kanagawa 259-1293 Japan
| | - Jun Nakanishi
- International Center for Materials Nanoarchitectonics (WPI-MANA); National Institute for Materials Science (NIMS); 1-1 Namiki, Tsukuba Ibaraki 305-0044 Japan
- Graduate School of Advanced Science and Engineering; Waseda University; 3-4-1 Okubo, Shinjuku-ku Tokyo 169-8555 Japan
| |
Collapse
|
5
|
Miyoshi H, Suzuki K, Ju J, Ko JS, Adachi T, Yamagata Y. A Perturbation Analysis to Understand the Mechanism How Migrating Cells Sense and Respond to a Topography in the Extracellular Environment. ANAL SCI 2018; 32:1207-1211. [PMID: 27829627 DOI: 10.2116/analsci.32.1207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Migrating cells in vivo monitor the physiological state of an organism by integrating the physical as well as chemical cues in the extracellular microenvironment, and alter the migration mode, in order to achieve their unique function. The clarification of the mechanism focusing on the topographical cues is important for basic biological research, and for biomedical engineering specifically to establish the design concept of tissue engineering scaffolds. The aim of this study is to understand how cells sense and respond to the complex topographical cues in vivo by exploring in vitro analyses to complex in vivo situations in order to simplify the issue. Since the intracellular mechanical events at subcellular scales and the way of the coordination of these events are supposed to change in the migrating cells, a key to success of the analysis is a mechanical point of view with a particular focus of the subcellular mechanical events. We designed an experimental platform to explore the mechanical requirements in a migrating fibroma cell responding to micro-grooves. The micro-grooved structure is a model of gap structures, typically seen in the microenvironments in vivo. In our experiment, the contributions of actomyosin force generation can be spatially divided and analyzed in the cell center and peripheral regions. The analysis specified that rapid leading edge protrusion, and the cell body translocation coordinated with the leading edge protrusion are required for the turning response at a micro-groove.
Collapse
Affiliation(s)
- Hiromi Miyoshi
- Pathophysiological and Health Science Team, RIKEN Center for Life Science Technologies
| | | | | | | | | | | |
Collapse
|
6
|
Dalier F, Dubacheva GV, Coniel M, Zanchi D, Galtayries A, Piel M, Marie E, Tribet C. Mixed Copolymer Adlayers Allowing Reversible Thermal Control of Single Cell Aspect Ratio. ACS APPLIED MATERIALS & INTERFACES 2018; 10:2253-2258. [PMID: 29314825 DOI: 10.1021/acsami.7b18513] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Dynamic guidance of living cells is achieved by fine-tuning and spatiotemporal modulation on artificial polymer layers enabling reversible peptide display. Adjustment of surface composition and interactions is obtained by coadsorption of mixed poly(lysine) derivatives, grafted with either repellent PEG, RGD adhesion peptides, or T-responsive poly(N-isopropylacrylamide) strands. Deposition of mixed adlayers provides a straightforward mean to optimize complex substrates, which is here implemented to achieve (1) thermal control of ligand accessibility and (2) adjustment of relative adhesiveness between adjacent micropatterns, while preserving cell attachment during thermal cycles. The reversible polarization of HeLa cells along orthogonal stripes mimics guidance along natural matrices.
Collapse
Affiliation(s)
- F Dalier
- PASTEUR, Département Chimie, Ecole Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC Université Paris 06, CNRS , 75005 Paris, France
| | - G V Dubacheva
- PASTEUR, Département Chimie, Ecole Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC Université Paris 06, CNRS , 75005 Paris, France
| | - M Coniel
- PASTEUR, Département Chimie, Ecole Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC Université Paris 06, CNRS , 75005 Paris, France
| | - D Zanchi
- PASTEUR, Département Chimie, Ecole Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC Université Paris 06, CNRS , 75005 Paris, France
- Université de Paris 7 Denis Diderot , 5 rue Thomas Mann, 75013 Paris, France
| | | | | | - E Marie
- PASTEUR, Département Chimie, Ecole Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC Université Paris 06, CNRS , 75005 Paris, France
| | - C Tribet
- PASTEUR, Département Chimie, Ecole Normale Supérieure, PSL Research University, Sorbonne Universités, UPMC Université Paris 06, CNRS , 75005 Paris, France
| |
Collapse
|
7
|
|
8
|
Tan G, Liu Y, Wu Y, Ouyang K, Zhou L, Yu P, Liao J, Ning C. Electrically Reversible Redox-Switchable Polydopamine Films for Regulating Cell Behavior. Electrochim Acta 2017. [DOI: 10.1016/j.electacta.2016.12.189] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
9
|
Nakanishi J. Photoactivatable Substrates: A Material-Based Approach for Dissecting Cell Migration. CHEM REC 2016; 17:611-621. [DOI: 10.1002/tcr.201600090] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Jun Nakanishi
- International Center for Materials Nanoarchitectonics (MANA); National Institute for Materials Science (NIMS); 1-1 Namiki Tsukuba 305-0044 Japan
| |
Collapse
|
10
|
Okano K, Hsu HY, Li YK, Masuhara H. In situ patterning and controlling living cells by utilizing femtosecond laser. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2016. [DOI: 10.1016/j.jphotochemrev.2016.07.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|
11
|
Ariga K, Minami K, Ebara M, Nakanishi J. What are the emerging concepts and challenges in NANO? Nanoarchitectonics, hand-operating nanotechnology and mechanobiology. Polym J 2016. [DOI: 10.1038/pj.2016.8] [Citation(s) in RCA: 155] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
12
|
Yamamoto H, Demura T, Sekine K, Kono S, Niwano M, Hirano-Iwata A, Tanii T. Photopatterning Proteins and Cells in Aqueous Environment Using TiO2 Photocatalysis. J Vis Exp 2015:e53045. [PMID: 26554338 PMCID: PMC4692672 DOI: 10.3791/53045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Organic contaminants adsorbed on the surface of titanium dioxide (TiO2) can be decomposed by photocatalysis under ultraviolet (UV) light. Here we describe a novel protocol employing the TiO2 photocatalysis to locally alter cell affinity of the substrate surface. For this experiment, a thin TiO2 film was sputter-coated on a glass coverslip, and the TiO2 surface was subsequently modified with an organosilane monolayer derived from octadecyltrichlorosilane (OTS), which inhibits cell adhesion. The sample was immersed in a cell culture medium, and focused UV light was irradiated to an octagonal region. When a neuronal cell line PC12 cells were plated on the sample, cells adhered only on the UV-irradiated area. We further show that this surface modification can also be performed in situ, i.e., even when cells are growing on the substrate. Proper modification of the surface required an extracellular matrix protein collagen to be present in the medium at the time of UV irradiation. The technique presented here can potentially be employed in patterning multiple cell types for constructing coculture systems or to arbitrarily manipulate cells under culture.
Collapse
Affiliation(s)
- Hideaki Yamamoto
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University; CREST, Japan Science and Technology Agency;
| | - Takanori Demura
- School of Fundamental Science and Engineering, Waseda University
| | - Kohei Sekine
- School of Fundamental Science and Engineering, Waseda University
| | - Sho Kono
- School of Fundamental Science and Engineering, Waseda University
| | - Michio Niwano
- CREST, Japan Science and Technology Agency; Research Institute of Electrical Communication, Tohoku University
| | - Ayumi Hirano-Iwata
- CREST, Japan Science and Technology Agency; Graduate School of Biomedical Engineering, Tohoku University
| | - Takashi Tanii
- Faculty of Science and Engineering, Waseda University
| |
Collapse
|
13
|
A molecular smart surface for spatio-temporal studies of cell mobility. PLoS One 2015; 10:e0118126. [PMID: 26030281 PMCID: PMC4452080 DOI: 10.1371/journal.pone.0118126] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 01/07/2015] [Indexed: 11/19/2022] Open
Abstract
Active migration in both healthy and malignant cells requires the integration of information derived from soluble signaling molecules with positional information gained from interactions with the extracellular matrix and with other cells. How a cell responds and moves involves complex signaling cascades that guide the directional functions of the cytoskeleton as well as the synthesis and release of proteases that facilitate movement through tissues. The biochemical events of the signaling cascades occur in a spatially and temporally coordinated manner then dynamically shape the cytoskeleton in specific subcellular regions. Therefore, cell migration and invasion involve a precise but constantly changing subcellular nano-architecture. A multidisciplinary effort that combines new surface chemistry and cell biological tools is required to understand the reorganization of cytoskeleton triggered by complex signaling during migration. Here we generate a class of model substrates that modulate the dynamic environment for a variety of cell adhesion and migration experiments. In particular, we use these dynamic substrates to probe in real-time how the interplay between the population of cells, the initial pattern geometry, ligand density, ligand affinity and integrin composition affects cell migration and growth. Whole genome microarray analysis indicates that several classes of genes ranging from signal transduction to cytoskeletal reorganization are differentially regulated depending on the nature of the surface conditions.
Collapse
|
14
|
Kamimura M, Scheideler O, Shimizu Y, Yamamoto S, Yamaguchi K, Nakanishi J. Facile preparation of a photoactivatable surface on a 96-well plate: a versatile and multiplex cell migration assay platform. Phys Chem Chem Phys 2015; 17:14159-67. [DOI: 10.1039/c5cp01499a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel photoactivatable 96-well plate based on photocleavable PEG and poly-d-lysine serves as a useful high-throughput cell migration assay platform.
Collapse
Affiliation(s)
- Masao Kamimura
- World Premier International (WPI) Research Center Initiative
- International Center for Materials Nanoarchitectonics (MANA)
- National Institute for Materials Science (NIMS)
- Tsukuba 305-0044
- Japan
| | - Olivia Scheideler
- World Premier International (WPI) Research Center Initiative
- International Center for Materials Nanoarchitectonics (MANA)
- National Institute for Materials Science (NIMS)
- Tsukuba 305-0044
- Japan
| | - Yoshihisa Shimizu
- World Premier International (WPI) Research Center Initiative
- International Center for Materials Nanoarchitectonics (MANA)
- National Institute for Materials Science (NIMS)
- Tsukuba 305-0044
- Japan
| | - Shota Yamamoto
- Department of Chemistry
- Faculty of Science
- Research Institute for Photofunctionalized Materials
- Kanagawa University
- Hiratsuka
| | - Kazuo Yamaguchi
- Department of Chemistry
- Faculty of Science
- Research Institute for Photofunctionalized Materials
- Kanagawa University
- Hiratsuka
| | - Jun Nakanishi
- World Premier International (WPI) Research Center Initiative
- International Center for Materials Nanoarchitectonics (MANA)
- National Institute for Materials Science (NIMS)
- Tsukuba 305-0044
- Japan
| |
Collapse
|
15
|
Pulsipher A, Park S, Dutta D, Luo W, Yousaf MN. In situ modulation of cell behavior via smart dual-ligand surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:13656-66. [PMID: 25373713 PMCID: PMC4334223 DOI: 10.1021/la503521x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Due to the highly complex nature of the extracellular matrix (ECM), the design and implementation of dynamic, stimuli-responsive surfaces that present well-defined ligands and serve as model ECM substrates have been of tremendous interest to biomaterials, biosensor, and cell biology communities. Such tools provide strategies for identifying specific ligand-receptor interactions that induce vital biological consequences. Herein, we report a novel dual-ligand-presenting surface methodology that modulates dynamic ECM properties to investigate various cell behaviors. Peptides PHSRN, cRGD, and KKKTTK, which mimic the cell- and heparan sulfate-binding domains of fibronectin, and carbohydrates Gal and Man were combined with cell adhesive RGD to survey possible synergistic or antagonist ligand effects on cell adhesion, spreading, growth, and migration. Soluble molecule and enzymatic inhibition assays were also performed, and the levels of focal adhesion kinase in cells subjected to different ligand combinations were quantified. A redox-responsive trigger was incorporated into this surface strategy to spontaneously release ligands in the presence of adhered cells, and cell spreading, growth, and migration responses were measured and compared. The identity and nature of the dual-ligand combination directly influenced cell behavior.
Collapse
Affiliation(s)
- Abigail Pulsipher
- Department
of Chemistry, University of North Carolina
at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Sungjin Park
- Department
of Chemistry, University of North Carolina
at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Debjit Dutta
- Department
of Chemistry, University of North Carolina
at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
| | - Wei Luo
- Department
of Chemistry, University of North Carolina
at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department
of Chemistry and Biology, York University, Toronto, Ontario M3J 1P3, Canada
| | - Muhammad N. Yousaf
- Department
of Chemistry, University of North Carolina
at Chapel Hill, Chapel Hill, North Carolina 27599-3290, United States
- Department
of Chemistry and Biology, York University, Toronto, Ontario M3J 1P3, Canada
- E-mail: . Tel: (416) 736-2100, ext
77718
| |
Collapse
|
16
|
A photoactivatable nanopatterned substrate for analyzing collective cell migration with precisely tuned cell-extracellular matrix ligand interactions. PLoS One 2014; 9:e91875. [PMID: 24632806 PMCID: PMC3954836 DOI: 10.1371/journal.pone.0091875] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 02/17/2014] [Indexed: 11/19/2022] Open
Abstract
Collective cell migration is involved in many biological and pathological processes. Various factors have been shown to regulate the decision to migrate collectively or individually, but the impact of cell-extracellular matrix (ECM) interactions is still debated. Here, we developed a method for analyzing collective cell migration by precisely tuning the interactions between cells and ECM ligands. Gold nanoparticles are arrayed on a glass substrate with a defined nanometer spacing by block copolymer micellar nanolithography (BCML), and photocleavable poly(ethylene glycol) (Mw = 12 kDa, PEG12K) and a cyclic RGD peptide, as an ECM ligand, are immobilized on this substrate. The remaining glass regions are passivated with PEG2K-silane to make cells interact with the surface via the nanoperiodically presented cyclic RGD ligands upon the photocleavage of PEG12K. On this nanostructured substrate, HeLa cells are first patterned in photo-illuminated regions, and cell migration is induced by a second photocleavage of the surrounding PEG12K. The HeLa cells gradually lose their cell-cell contacts and become disconnected on the nanopatterned substrate with 10-nm particles and 57-nm spacing, in contrast to their behavior on the homogenous substrate. Interestingly, the relationship between the observed migration collectivity and the cell-ECM ligand interactions is the opposite of that expected based on conventional soft matter models. It is likely that the reduced phosphorylation at tyrosine-861 of focal adhesion kinase (FAK) on the nanopatterned surface is responsible for this unique migration behavior. These results demonstrate the usefulness of the presented method in understanding the process of determining collective and non-collective migration features in defined micro- and nano-environments and resolving the crosstalk between cell-cell and cell-ECM adhesions.
Collapse
|