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Selcuk K, Leitner A, Braun L, Le Blanc F, Pacak P, Pot S, Vogel V. Transglutaminase 2 has higher affinity for relaxed than for stretched fibronectin fibers. Matrix Biol 2024; 125:113-132. [PMID: 38135164 DOI: 10.1016/j.matbio.2023.12.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 11/20/2023] [Accepted: 12/18/2023] [Indexed: 12/24/2023]
Abstract
Transglutaminase 2 (TG2) plays a vital role in stabilizing extracellular matrix (ECM) proteins through enzymatic crosslinking during tissue growth, repair, and inflammation. TG2 also binds non-covalently to fibronectin (FN), an essential component of the ECM, facilitating cell adhesion, migration, proliferation, and survival. However, the interaction between TG2 and fibrillar FN remains poorly understood, as most studies have focused on soluble or surface-adsorbed FN or FN fragments, which differ in their conformations from insoluble FN fibers. Using a well-established in vitro FN fiber stretch assay, we discovered that the binding of a crosslinking enzyme to ECM fibers is mechano-regulated. TG2 binding to FN is tuned by the mechanical tension of FN fibers, whereby TG2 predominantly co-localizes to low-tension FN fibers, while fiber stretching reduces their affinity for TG2. This mechano-regulated binding relies on the proximity between the N-terminal β-sandwich and C-terminal β-barrels of TG2. Crosslinking mass spectrometry (XL-MS) revealed a novel TG2-FN synergy site within TG2's C-terminal β-barrels that interacts with FN regions located outside of the canonical gelatin binding domain, specifically FNI2 and FNIII14-15. Combining XL-MS distance restraints with molecular docking revealed the mechano-regulated binding mechanism between TG2 and modules FNI7-9 by which mechanical forces regulate TG2-FN interactions. This highlights a previously unrecognized role of TG2 as a tension sensor for FN fibers. This novel interaction mechanism has significant implications in physiology and mechanobiology, including how forces regulate cell adhesion, spreading, migration, phenotype modulation, depending on the tensional state of ECM fibers. Data are available via ProteomeXchange with identifier PXD043976.
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Affiliation(s)
- Kateryna Selcuk
- Department of Health Sciences and Technology, Institute of Translational Medicine, Laboratory of Applied Mechanobiology, ETH Zurich, Gloriastrasse 37-39 GLC G11, CH-8092 Zurich, Switzerland
| | - Alexander Leitner
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Otto-Stern-Weg 3, CH-8093 Zurich, Switzerland
| | - Lukas Braun
- Department of Health Sciences and Technology, Institute of Translational Medicine, Laboratory of Applied Mechanobiology, ETH Zurich, Gloriastrasse 37-39 GLC G11, CH-8092 Zurich, Switzerland
| | - Fanny Le Blanc
- Department of Biology, Institute of Molecular Systems Biology, ETH Zurich, Otto-Stern-Weg 3, CH-8093 Zurich, Switzerland
| | - Paulina Pacak
- Department of Health Sciences and Technology, Institute of Translational Medicine, Laboratory of Applied Mechanobiology, ETH Zurich, Gloriastrasse 37-39 GLC G11, CH-8092 Zurich, Switzerland
| | - Simon Pot
- Department of Health Sciences and Technology, Institute of Translational Medicine, Laboratory of Applied Mechanobiology, ETH Zurich, Gloriastrasse 37-39 GLC G11, CH-8092 Zurich, Switzerland
| | - Viola Vogel
- Department of Health Sciences and Technology, Institute of Translational Medicine, Laboratory of Applied Mechanobiology, ETH Zurich, Gloriastrasse 37-39 GLC G11, CH-8092 Zurich, Switzerland.
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Hedayati M, Chen YI, Houser JR, Wang Y, Norouzi S, Yeh HC, Parekh SH. Visualizing molecular deformation in fibrin networks under tensile loading via FLIM-FRET. Chem Commun (Camb) 2023; 59:14575-14578. [PMID: 37988171 DOI: 10.1039/d3cc05281h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2023]
Abstract
Mapping molecular deformation and forces in protein biomaterials is critical to understanding mechanochemistry. Here we use intramolecular Förster resonance energy transfer (FRET) of dual-labeled fibrin to distinguish molecular conformations of proteins in situ during mechanical loading. The FRET approach offers increased spatial resolution compared to our previous vibrational imaging. By using fluorescence lifetime microscopy (FLIM), we demonstrate that the combination of FRET and FLIM can probe the molecular changes in fibrin with high spatial (nanometer) and temporal (nanosecond) resolution. Our results map changes in fibrin monomer deformation during the macroscopic loading of the fibrin network, paving the way to directly visualizing the biomaterial mechanics and structure in cell-ECM scaffolds for the first time.
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Affiliation(s)
| | - Yuan-I Chen
- Biomedical Engineering, University of Texas at Austin, Austin, TX, USA.
| | - Justin R Houser
- Biomedical Engineering, University of Texas at Austin, Austin, TX, USA.
| | - Yujen Wang
- Biomedical Engineering, University of Texas at Austin, Austin, TX, USA.
| | - Sajjad Norouzi
- Biomedical Engineering, University of Texas at Austin, Austin, TX, USA.
| | - Hsin-Chih Yeh
- Biomedical Engineering, University of Texas at Austin, Austin, TX, USA.
- Texas Materials Institute, University of Texas at Austin, Austin, TX, USA
| | - Sapun H Parekh
- Biomedical Engineering, University of Texas at Austin, Austin, TX, USA.
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3
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Wu J, Lin C, Yang C, Pan L, Liu H, Zhu S, Wei S, Jia X, Zhang Q, Yu Z, Zhao X, Liu W, Zhuo Y, Wang N. Identification and validation of key biomarkers and potential therapeutic targets for primary open-angle glaucoma. SCIENCE CHINA. LIFE SCIENCES 2023; 66:2837-2850. [PMID: 37610681 DOI: 10.1007/s11427-022-2344-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 04/06/2023] [Indexed: 08/24/2023]
Abstract
Primary open-angle glaucoma (POAG) is a prevalent cause of blindness worldwide, resulting in degeneration of retinal ganglion cells and permanent damage to the optic nerve. However, the underlying pathogenetic mechanisms of POAG are currently indistinct, and there has been no effective nonsurgical treatment regimen. The objective of this study is to identify novel biomarkers and potential therapeutic targets for POAG. The mRNA expression microarray datasets GSE27276 and GSE138125, as well as the single-cell high-throughput RNA sequencing (scRNA-seq) dataset GSE148371 were utilized to screen POAG-related differentially expressed genes (DEGs). Functional enrichment analyses, protein-protein interaction (PPI) analysis, and weighted gene co-expression network analysis (WGCNA) of the DEGs were performed. Subsequently, the hub genes were validated at a single-cell level, where trabecular cells were annotated, and the mRNA expression levels of target genes in different cell clusters were analyzed. Immunofluorescence and quantitative real-time PCR (qPCR) were performed for further validation. DEGs analysis identified 43 downregulated and 32 upregulated genes in POAG, which were mainly enriched in immune-related pathways, oxidative stress, and endoplasmic reticulum (ER) stress. PPI networks showed that FN1 and DUSP1 were the central hub nodes, while GPX3 and VAV3 were screened out as hub genes through WGCNA and subsequently validated by qPCR. Finally, FN1, GPX3, and VAV3 were determined to be pivotal core genes via single-cell validation. The relevant biomarkers involved in the pathogenesis of POAG, may serve as potential therapeutic targets. Further studies are necessary to unveil the mechanisms underlying the expression variations of these genes in POAG.
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Affiliation(s)
- Jian Wu
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing, 100730, China
| | - Caixia Lin
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, 100730, China
| | - Chenlong Yang
- Department of Neurosurgery, Peking University Third Hospital, Center for Precision Neurosurgery and Oncology of Peking University Health Science Center, Beijing, 100191, China
- North America Medical Education Foundation, Union City, CA, 94539, USA
| | - Lijie Pan
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing, 100730, China
| | - Hongyi Liu
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing, 100730, China
| | - Sirui Zhu
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing, 100730, China
| | - Shuwen Wei
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing, 100730, China
| | - Xu Jia
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510060, China
| | - Qi Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510060, China
| | - Ziyu Yu
- Spencer Center for Vision Research, Byers Eye Institute, School of Medicine, Stanford University, Palo Alto, CA, 94304, USA
| | - Xiaofang Zhao
- Department of Neurosurgery, Peking University Third Hospital, Center for Precision Neurosurgery and Oncology of Peking University Health Science Center, Beijing, 100191, China
| | - Weihai Liu
- Department of Neurosurgery, Peking University Third Hospital, Center for Precision Neurosurgery and Oncology of Peking University Health Science Center, Beijing, 100191, China
| | - Yehong Zhuo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, 510060, China.
| | - Ningli Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Key Laboratory of Ophthalmology and Visual Sciences, Beijing, 100730, China.
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Abalymov A, Pinchasik BE, Akasov RA, Lomova M, Parakhonskiy BV. Strategies for Anisotropic Fibrillar Hydrogels: Design, Cell Alignment, and Applications in Tissue Engineering. Biomacromolecules 2023; 24:4532-4552. [PMID: 37812143 DOI: 10.1021/acs.biomac.3c00503] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Efficient cellular alignment in biomaterials presents a considerable challenge, demanding the refinement of appropriate material morphologies, while ensuring effective cell-surface interactions. To address this, biomaterials are continuously researched with diverse coatings, hydrogels, and polymeric surfaces. In this context, we investigate the influence of physicochemical parameters on the architecture of fibrillar hydrogels that significantly orient the topography of flexible hydrogel substrates, thereby fostering cellular adhesion and spatial organization. Our Review comprehensively assesses various techniques for aligning polymer fibrils within hydrogels, specifically interventions applied during and after the cross-linking process. These methodologies include mechanical strains, precise temperature modulation, controlled fluidic dynamics, and chemical modulators, as well as the use of magnetic and electric fields. We highlight the intrinsic appeal of these methodologies in fabricating cell-aligning interfaces and discuss their potential implications within the fields of biomaterials and tissue engineering, particularly concerning the pursuit of optimal cellular alignment.
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Affiliation(s)
- Anatolii Abalymov
- Science Medical Center, Saratov State University, 410012 Saratov, Russia
| | - Bat-El Pinchasik
- School of Mechanical Engineering, Faculty of Engineering, Tel-Aviv University, 69978 Tel-Aviv, Israel
| | - Roman A Akasov
- Sechenov University and Federal Scientific Research Centre "Crystallography and Photonics" of Russian Academy of Sciences, 101000 Moscow, Russia
| | - Maria Lomova
- Science Medical Center, Saratov State University, 410012 Saratov, Russia
| | - Bogdan V Parakhonskiy
- Department of Biotechnology, Faculty of Bioscience Engineering, Ghent University, 9000 Ghent, Belgium
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5
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Bashiri G, Padilla MS, Swingle KL, Shepherd SJ, Mitchell MJ, Wang K. Nanoparticle protein corona: from structure and function to therapeutic targeting. LAB ON A CHIP 2023; 23:1432-1466. [PMID: 36655824 PMCID: PMC10013352 DOI: 10.1039/d2lc00799a] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 11/29/2022] [Indexed: 05/31/2023]
Abstract
Nanoparticle (NP)-based therapeutics have ushered in a new era in translational medicine. However, despite the clinical success of NP technology, it is not well-understood how NPs fundamentally change in biological environments. When introduced into physiological fluids, NPs are coated by proteins, forming a protein corona (PC). The PC has the potential to endow NPs with a new identity and alter their bioactivity, stability, and destination. Additionally, the conformation of proteins is sensitive to their physical and chemical surroundings. Therefore, biological factors and protein-NP-interactions can induce changes in the conformation and orientation of proteins in vivo. Since the function of a protein is closely connected to its folded structure, slight differences in the surrounding environment as well as the surface characteristics of the NP materials may cause proteins to lose or gain a function. As a result, this can alter the downstream functionality of the NPs. This review introduces the main biological factors affecting the conformation of proteins associated with the PC. Then, four types of NPs with extensive utility in biomedical applications are described in greater detail, focusing on the conformation and orientation of adsorbed proteins. This is followed by a discussion on the instances in which the conformation of adsorbed proteins can be leveraged for therapeutic purposes, such as controlling protein conformation in assembled matrices in tissue, as well as controlling the PC conformation for modulating immune responses. The review concludes with a perspective on the remaining challenges and unexplored areas at the interface of PC and NP research.
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Affiliation(s)
- Ghazal Bashiri
- Department of Bioengineering, Temple University, Philadelphia, PA 19122, USA.
| | - Marshall S Padilla
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kelsey L Swingle
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sarah J Shepherd
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Michael J Mitchell
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA 19104, USA
- Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Institute for Immunology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Institute for Regenerative Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Karin Wang
- Department of Bioengineering, Temple University, Philadelphia, PA 19122, USA.
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Blache U, Ford EM, Ha B, Rijns L, Chaudhuri O, Dankers PY, Kloxin AM, Snedeker JG, Gentleman E. Engineered hydrogels for mechanobiology. NATURE REVIEWS. METHODS PRIMERS 2022; 2:98. [PMID: 37461429 PMCID: PMC7614763 DOI: 10.1038/s43586-022-00179-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 10/17/2022] [Indexed: 07/20/2023]
Abstract
Cells' local mechanical environment can be as important in guiding cellular responses as many well-characterized biochemical cues. Hydrogels that mimic the native extracellular matrix can provide these mechanical cues to encapsulated cells, allowing for the study of their impact on cellular behaviours. Moreover, by harnessing cellular responses to mechanical cues, hydrogels can be used to create tissues in vitro for regenerative medicine applications and for disease modelling. This Primer outlines the importance and challenges of creating hydrogels that mimic the mechanical and biological properties of the native extracellular matrix. The design of hydrogels for mechanobiology studies is discussed, including appropriate choice of cross-linking chemistry and strategies to tailor hydrogel mechanical cues. Techniques for characterizing hydrogels are explained, highlighting methods used to analyze cell behaviour. Example applications for studying fundamental mechanobiological processes and regenerative therapies are provided, along with a discussion of the limitations of hydrogels as mimetics of the native extracellular matrix. The article ends with an outlook for the field, focusing on emerging technologies that will enable new insights into mechanobiology and its role in tissue homeostasis and disease.
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Affiliation(s)
- Ulrich Blache
- Fraunhofer Institute for Cell Therapy and Immunology and Fraunhofer Cluster of Excellence for Immune-Mediated Disease, Leipzig, Germany
| | - Eden M. Ford
- Department of Chemical and Biomolecular Engineering, University of Delaware, DE, USA
| | - Byunghang Ha
- Department of Mechanical Engineering, Stanford University, CA, USA
| | - Laura Rijns
- Institute for Complex Molecular Systems, Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
| | - Ovijit Chaudhuri
- Department of Mechanical Engineering, Stanford University, CA, USA
| | - Patricia Y.W. Dankers
- Institute for Complex Molecular Systems, Department of Biomedical Engineering, Laboratory of Chemical Biology, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
| | - April M. Kloxin
- Department of Chemical and Biomolecular Engineering, University of Delaware, DE, USA
- Department of Material Science and Engineering, University of Delaware, DE, USA
| | - Jess G. Snedeker
- University Hospital Balgrist and ETH Zurich, Zurich, Switzerland
| | - Eileen Gentleman
- Centre for Craniofacial and Regenerative Biology, King’s College London, London SE1 9RT, UK
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Jones CE, Sharick JT, Sizemore ST, Cukierman E, Strohecker AM, Leight JL. A miniaturized screening platform to identify novel regulators of extracellular matrix alignment. CANCER RESEARCH COMMUNICATIONS 2022; 2:1471-1486. [PMID: 36530465 PMCID: PMC9757767 DOI: 10.1158/2767-9764.crc-22-0157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Revised: 08/03/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022]
Abstract
Extracellular matrix alignment contributes to metastasis in a number of cancers and is a known prognostic stromal factor; however, the mechanisms controlling matrix organization remain unclear. Cancer-associated fibroblasts (CAF) play a critical role in this process, particularly via matrix production and modulation of key signaling pathways controlling cell adhesion and contractility. Stroma normalization, as opposed to elimination, is a highly sought strategy, and screening for drugs that effectively alter extracellular matrix (ECM) alignment is a practical way to identify novel CAF-normalizing targets that modulate ECM organization. To meet this need, we developed a novel high-throughput screening platform in which fibroblast-derived matrices were produced in 384-well plates, imaged with automated confocal microscopy, and analyzed using a customized MATLAB script. This platform is a technical advance because it miniaturizes the assay, eliminates costly and time-consuming experimental steps, and streamlines data acquisition and analysis to enable high-throughput screening applications. As a proof of concept, this platform was used to screen a kinase inhibitor library to identify modulators of matrix alignment. A number of novel potential regulators were identified, including several receptor tyrosine kinases (c-MET, tropomyosin receptor kinase 1 (NTRK1), HER2/ERBB2) and the serine/threonine kinases protein kinase A, C, and G (PKA, PKC, and PKG). The expression of these regulators was analyzed in publicly available patient datasets to examine the association between stromal gene expression and patient outcomes.
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Affiliation(s)
- Caitlin E. Jones
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
| | - Joe T. Sharick
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
- The James Comprehensive Cancer Center, Program in Cancer Biology, The Ohio State University, Columbus, Ohio
| | - Steven T. Sizemore
- The James Comprehensive Cancer Center, Program in Cancer Biology, The Ohio State University, Columbus, Ohio
- Department of Radiation Oncology, The Ohio State University, Columbus, Ohio
| | - Edna Cukierman
- Cancer Signaling and Epigenetics, The Marvin and Concetta Greenberg Pancreatic Cancer Institute, Fox Chase Cancer Center, Temple Health, Philadelphia, Pennsylvania
| | - Anne Marie Strohecker
- The James Comprehensive Cancer Center, Program in Cancer Biology, The Ohio State University, Columbus, Ohio
- Department of Cancer Biology and Genetics, The Ohio State University, Columbus, Ohio
| | - Jennifer L. Leight
- Department of Biomedical Engineering, The Ohio State University, Columbus, Ohio
- The James Comprehensive Cancer Center, Program in Cancer Biology, The Ohio State University, Columbus, Ohio
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8
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Khan N, Aslan H, Büttner H, Rohde H, Golbek TW, Roeters SJ, Woutersen S, Weidner T, Meyer RL. The giant staphylococcal protein Embp facilitates colonization of surfaces through Velcro-like attachment to fibrillated fibronectin. eLife 2022; 11:76164. [PMID: 35796649 PMCID: PMC9302970 DOI: 10.7554/elife.76164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 06/17/2022] [Indexed: 11/13/2022] Open
Abstract
Staphylococcus epidermidis causes some of the most hard-to-treat clinical infections by forming biofilms: Multicellular communities of bacteria encased in a protective matrix, supporting immune evasion and tolerance against antibiotics. Biofilms occur most commonly on medical implants, and a key event in implant colonization is the robust adherence to the surface, facilitated by interactions between bacterial surface proteins and host matrix components. S. epidermidis is equipped with a giant adhesive protein, extracellular matrix-binding protein (Embp), which facilitates bacterial interactions with surface-deposited, but not soluble fibronectin. The structural basis behind this selective binding process has remained obscure. Using a suite of single-cell and single-molecule analysis techniques, we show that S. epidermidis is capable of such distinction because Embp binds specifically to fibrillated fibronectin on surfaces, while ignoring globular fibronectin in solution. S. epidermidis adherence is critically dependent on multivalent interactions involving 50 fibronectin-binding repeats of Embp. This unusual, Velcro-like interaction proved critical for colonization of surfaces under high flow, making this newly identified attachment mechanism particularly relevant for colonization of intravascular devices, such as prosthetic heart valves or vascular grafts. Other biofilm-forming pathogens, such as Staphylococcus aureus, express homologs of Embp and likely deploy the same mechanism for surface colonization. Our results may open for a novel direction in efforts to combat devastating, biofilm-associated infections, as the development of implant materials that steer the conformation of adsorbed proteins is a much more manageable task than avoiding protein adsorption altogether. A usually harmless bacterium called Staphylococcus epidermidis lives on human skin. Sometimes it makes its way into the bloodstream through a cut or surgical procedure, but it rarely causes blood infections. It can, however, cause severe infections when it attaches to the surface of a medical implant like a pacemaker or an artificial replacement joint. It does this by forming a colony of bacteria on the implant’s surface called a biofilm, which protects the bacteria from destruction by the immune system or antibiotics. Understanding how Staphylococcus epidermidis implant infections start is critical to preventing them. This information may help scientists develop infection-resistant implants or new treatments for implant infections. Scientists suspect that Staphylococcus epidermidis attaches to implants by binding to a human protein called fibronectin, which coats medical implants in the human body. Another protein on the surface of the bacteria, called Embp, facilitates the connection. But why the bacteria attach to fibronectin on implants, and not fibronectin molecules in the bloodstream, is unclear. Now, Khan, Aslan et al. show that Embp forms a Velcro-like bond with fibronectin on the surface of implants. In the experiments, Khan and Aslan et al. used powerful microscopes to create 3-dimensional images of the interactions between Embp and fibronectin. The experiments showed that Embp's attachment site is hidden on the globe-shaped form of fibronectin circulating in the blood. But when fibronectin covers an implant surface, it forms a fibrous network, and Embp can attach to it with up to 50 Velcro-like individual connections. These many weak connections form a strong bond that withstands the force of blood pumping past. The experiments show that the fibrous coating of fibronectin on implants makes them a hotspot for Staphylococcus epidermidis infections. Finding ways to block Embp from attaching to fibronectin on implants, or altering the form fibronectin takes on implants, may help prevent these infections. Many bacteria that form biofilms have an Embp-like protein. As a result, these discoveries may also help scientists develop prevention or treatment strategies for other bacterial biofilm infections.
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Affiliation(s)
- Nasar Khan
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark
| | - Hüsnü Aslan
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus, Denmark
| | - Henning Büttner
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Holger Rohde
- Institute for Medical Microbiology, Virology and Hygiene, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | | | | | - Sander Woutersen
- Van 't Hoff Institute of Molecular Sciences, University of Amsterdam, Amsterdam, Netherlands
| | - Tobias Weidner
- Department of Chemistry, Aarhus University, Aarhus C, Denmark
| | - Rikke Louise Meyer
- Interdisciplinary Nanoscience Center, Aarhus University, Aarhus C, Denmark
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9
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Keller KE, Peters DM. Pathogenesis of glaucoma: Extracellular matrix dysfunction in the trabecular meshwork-A review. Clin Exp Ophthalmol 2022; 50:163-182. [PMID: 35037377 DOI: 10.1111/ceo.14027] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/19/2021] [Accepted: 11/26/2021] [Indexed: 12/11/2022]
Abstract
The trabecular meshwork regulates aqueous humour outflow from the anterior chamber of the eye. It does this by establishing a tunable outflow resistance, defined by the interplay between cells and their extracellular matrix (ECM) milieu, and the molecular interactions between ECM proteins. During normal tissue homeostasis, the ECM is remodelled and trabecular cell behaviour is modified, permitting increased aqueous fluid outflow to maintain intraocular pressure (IOP) within a relatively narrow physiological pressure. Dysfunction in the normal homeostatic process leads to increased outflow resistance and elevated IOP, which is a primary risk factor for glaucoma. This review delineates some of the changes in the ECM that lead to gross as well as some more subtle changes in the structure and function of the ECM, and their impact on trabecular cell behaviour. These changes are discussed in the context of outflow resistance and glaucoma.
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Affiliation(s)
- Kate E Keller
- Casey Eye Institute, Oregon Health &Science University, Portland, Oregon, USA
| | - Donna M Peters
- Department of Pathology & Laboratory Medicine, University of Wisconsin School of Medicine & Public Health, Madison, Wisconsin, USA
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10
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Sahay P, Reddy S, Prusty BK, Modak R, Rao A. TGFβ1, MMPs and cytokines profiles in ocular surface: Possible tear biomarkers for pseudoexfoliation. PLoS One 2021; 16:e0249759. [PMID: 33914756 PMCID: PMC8084233 DOI: 10.1371/journal.pone.0249759] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 03/24/2021] [Indexed: 12/31/2022] Open
Abstract
Purpose Pseudoexfoliation (PXF) is a unique form of glaucoma characterized by accumulation of exfoliative material in the eyes. Changes in tear profile in disease stages may give us insights into molecular mechanisms involved in causing glaucoma in the eye. Methods All patients were categorized into three main categories; pseudoexfoliation (PXF), pseudoexfoliation glaucoma (PXG) and cataract, which served as control. Cytokines, transforming growth factor β1 (TGFβ1), matrix metalloproteases (MMPs) and fibronectin (FN1) were assessed with multiplex bead assay, enzyme-linked immunosorbent assay (ELISA), gelatin zymography, and immunohistochemistry (IHC) respectively in different ocular tissues such as tears, tenon’s capsule, aqueous humor (AH) and serum samples of patients with PXF stages. Results We found that TGFβ1, MMP-9 and FN1 protein expression were upregulated in tears, tenon’s capsule and AH samples in PXG compared to PXF, though the MMP-9 protein activity was downregulated in PXG compared with control or PXF. We have also found that in PXG tears sample the fold change of TGF-α (Transforming Growth Factor-α), MDC (Macrophage Derived Chemokine), IL-8 (Interleukin-8), VEGF (Vascular Endothelial Growth Factor) were significantly downregulated and the levels of GM-CSF (Granulocyte Macrophage Colony Stimulating Factor), IP-10 (Interferon- γ produced protein-10) were significant upregulated. While in AH; IL-6 (Interleukin-6), IL-8, VEGF, IFN-a2 (Interferon- α2), GRO (Growth regulated alpha protein) levels were found lower and IL1a (Interleukin-1α) level was higher in PXG compared to PXF. And in serum; IFN-a2, Eotaxin, GM-CSF, Fractalkine, IL-10 (Interleukin-10), IL1Ra (Interleukin-1 receptor antagonist), IL-7 (Interleukin-7), IL-8, MIP1β (Macrophage Inflammatory Protein-1β), MCP-1 (Monocyte Chemoattractant Protein-1) levels were significantly upregulated and PDGF-AA (Platelet Derived Growth Factor-AA) level was downregulated in the patients with PXG compared to PXF. Conclusions Altered expression of these molecules in tears may therefore be used as a signal for onset of glaucoma or for identifying eyes at risk of developing glaucoma in PXF.
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Affiliation(s)
- Prity Sahay
- Hyderabad Eye Research Foundation (HERF), L.V. Prasad Eye Institute, Patia, Bhubaneswar, Odisha, India
- KIIT School of Biotechnology, Patia, Bhubaneswar, Odisha, India
| | - Shweta Reddy
- Hyderabad Eye Research Foundation (HERF), L.V. Prasad Eye Institute, Patia, Bhubaneswar, Odisha, India
| | | | - Rahul Modak
- KIIT School of Biotechnology, Patia, Bhubaneswar, Odisha, India
- * E-mail: (RM); (AR)
| | - Aparna Rao
- Hyderabad Eye Research Foundation (HERF), L.V. Prasad Eye Institute, Patia, Bhubaneswar, Odisha, India
- KIIT School of Biotechnology, Patia, Bhubaneswar, Odisha, India
- * E-mail: (RM); (AR)
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11
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Spada S, Tocci A, Di Modugno F, Nisticò P. Fibronectin as a multiregulatory molecule crucial in tumor matrisome: from structural and functional features to clinical practice in oncology. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2021; 40:102. [PMID: 33731188 PMCID: PMC7972229 DOI: 10.1186/s13046-021-01908-8] [Citation(s) in RCA: 53] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Accepted: 03/09/2021] [Indexed: 12/11/2022]
Abstract
Deciphering extracellular matrix (ECM) composition and architecture may represent a novel approach to identify diagnostic and therapeutic targets in cancer. Among the ECM components, fibronectin and its fibrillary assembly represent the scaffold to build up the entire ECM structure, deeply affecting its features. Herein we focus on this extraordinary protein starting from its complex structure and defining its role in cancer as prognostic and theranostic marker.
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Affiliation(s)
- Sheila Spada
- Department of Radiation Oncology, Weill Cornell Medicine, New York, NY, USA
| | - Annalisa Tocci
- Tumor Immunology and Immunotherapy Unit, IRCCS-Regina Elena National Cancer Institute, Rome, Italy
| | - Francesca Di Modugno
- Tumor Immunology and Immunotherapy Unit, IRCCS-Regina Elena National Cancer Institute, Rome, Italy.
| | - Paola Nisticò
- Tumor Immunology and Immunotherapy Unit, IRCCS-Regina Elena National Cancer Institute, Rome, Italy.
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12
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Liu L, He F, Yu Y, Wang Y. Application of FRET Biosensors in Mechanobiology and Mechanopharmacological Screening. Front Bioeng Biotechnol 2020; 8:595497. [PMID: 33240867 PMCID: PMC7680962 DOI: 10.3389/fbioe.2020.595497] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 10/19/2020] [Indexed: 12/15/2022] Open
Abstract
Extensive studies have shown that cells can sense and modulate the biomechanical properties of the ECM within their resident microenvironment. Thus, targeting the mechanotransduction signaling pathways provides a promising way for disease intervention. However, how cells perceive these mechanical cues of the microenvironment and transduce them into biochemical signals remains to be answered. Förster or fluorescence resonance energy transfer (FRET) based biosensors are a powerful tool that can be used in live-cell mechanotransduction imaging and mechanopharmacological drug screening. In this review, we will first introduce FRET principle and FRET biosensors, and then, recent advances on the integration of FRET biosensors and mechanobiology in normal and pathophysiological conditions will be discussed. Furthermore, we will summarize the current applications and limitations of FRET biosensors in high-throughput drug screening and the future improvement of FRET biosensors. In summary, FRET biosensors have provided a powerful tool for mechanobiology studies to advance our understanding of how cells and matrices interact, and the mechanopharmacological screening for disease intervention.
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Affiliation(s)
| | | | | | - Yingxiao Wang
- Department of Bioengineering, Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA, United States
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13
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Yang JZ, Qiu LH, Xiong SH, Dang JL, Rong XK, Hou MM, Wang K, Yu Z, Yi CG. Decellularized adipose matrix provides an inductive microenvironment for stem cells in tissue regeneration. World J Stem Cells 2020; 12:585-603. [PMID: 32843915 PMCID: PMC7415251 DOI: 10.4252/wjsc.v12.i7.585] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 05/27/2020] [Accepted: 05/30/2020] [Indexed: 02/06/2023] Open
Abstract
Stem cells play a key role in tissue regeneration due to their self-renewal and multidirectional differentiation, which are continuously regulated by signals from the extracellular matrix (ECM) microenvironment. Therefore, the unique biological and physical characteristics of the ECM are important determinants of stem cell behavior. Although the acellular ECM of specific tissues and organs (such as the skin, heart, cartilage, and lung) can mimic the natural microenvironment required for stem cell differentiation, the lack of donor sources restricts their development. With the rapid development of adipose tissue engineering, decellularized adipose matrix (DAM) has attracted much attention due to its wide range of sources and good regeneration capacity. Protocols for DAM preparation involve various physical, chemical, and biological methods. Different combinations of these methods may have different impacts on the structure and composition of DAM, which in turn interfere with the growth and differentiation of stem cells. This is a narrative review about DAM. We summarize the methods for decellularizing and sterilizing adipose tissue, and the impact of these methods on the biological and physical properties of DAM. In addition, we also analyze the application of different forms of DAM with or without stem cells in tissue regeneration (such as adipose tissue), repair (such as wounds, cartilage, bone, and nerves), in vitro bionic systems, clinical trials, and other disease research.
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Affiliation(s)
- Ji-Zhong Yang
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Li-Hong Qiu
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Shao-Heng Xiong
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Juan-Li Dang
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Xiang-Ke Rong
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Meng-Meng Hou
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Kai Wang
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Zhou Yu
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Cheng-Gang Yi
- Department of Plastic Surgery, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
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14
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Fonta CM, Arnoldini S, Jaramillo D, Moscaroli A, Oxenius A, Behe M, Vogel V. Fibronectin fibers are highly tensed in healthy organs in contrast to tumors and virus-infected lymph nodes. Matrix Biol Plus 2020; 8:100046. [PMID: 33543039 PMCID: PMC7852196 DOI: 10.1016/j.mbplus.2020.100046] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 07/09/2020] [Accepted: 07/09/2020] [Indexed: 12/12/2022] Open
Abstract
The extracellular matrix (ECM) acts as reservoir for a plethora of growth factors and cytokines some of which are hypothesized to be regulated by ECM fiber tension. Yet, ECM fiber tension has never been mapped in healthy versus diseased organs. Using our recently developed tension nanoprobe derived from the bacterial adhesin FnBPA5, which preferentially binds to structurally relaxed fibronectin fibers, we discovered here that fibronectin fibers are kept under high tension in selected healthy mouse organs. In contrast, tumor tissues and virus-infected lymph nodes exhibited a significantly higher content of relaxed or proteolytically cleaved fibronectin fibers. This demonstrates for the first time that the tension of ECM fibers is significantly reduced upon pathological tissue transformations. This has wide implications, as the active stretching of fibronectin fibers adjusts critical cellular niche parameters and thereby tunes the reciprocal cell-ECM crosstalk. Mapping the tensional state of fibronectin fibers opens novel and unexpected diagnostic opportunities. Mechanobiology of extracellular matrix changes upon pathological transformations. Fibronectin is significantly more relaxed in tumors than in healthy organs. Relaxed fibronectin is found close to myofibroblasts and dense collagen fibers. Viral infection reduces fibronectin fiber tension in lymph nodes. Use of a tension-sensitive adhesin to probe fibronectin fiber tension in tissues
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Key Words
- CAFs, cancer associated fibroblasts
- CLEC-2, C-type Lectin Receptor
- Cancer
- DCs, dendritic cells
- ECM, extracellular matrix
- Extracellular matrix
- FRCs, fibroblastic reticular cells
- Fibronectin
- IHC, immunohistochemistry
- IL-7, Interleukin 7
- LCMV, lymphocytic choriomeningitis virus
- Lymph node
- MMPs, matrix metalloproteinases
- Mechanobiology
- PDPN, podoplanin
- SHG, second harmonic generation
- TGF-β, Transforming Growth Factor-beta
- Virus infection
- α-SMA, alpha smooth muscle actin
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Affiliation(s)
- Charlotte M Fonta
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Sciences and Technology, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Simon Arnoldini
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Sciences and Technology, ETH Zurich, CH-8093 Zurich, Switzerland
| | | | - Alessandra Moscaroli
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - Annette Oxenius
- Institute of Microbiology, ETH Zürich, CH-8093 Zurich, Switzerland
| | - Martin Behe
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
| | - Viola Vogel
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Sciences and Technology, ETH Zurich, CH-8093 Zurich, Switzerland
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15
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Jain N, Moeller J, Vogel V. Mechanobiology of Macrophages: How Physical Factors Coregulate Macrophage Plasticity and Phagocytosis. Annu Rev Biomed Eng 2020; 21:267-297. [PMID: 31167103 DOI: 10.1146/annurev-bioeng-062117-121224] [Citation(s) in RCA: 136] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In addition to their early-recognized functions in host defense and the clearance of apoptotic cell debris, macrophages play vital roles in tissue development, homeostasis, and repair. If misregulated, they steer the progression of many inflammatory diseases. Much progress has been made in understanding the mechanisms underlying macrophage signaling, transcriptomics, and proteomics, under physiological and pathological conditions. Yet, the detailed mechanisms that tune circulating monocytes/macrophages and tissue-resident macrophage polarization, differentiation, specification, and their functional plasticity remain elusive. We review how physical factors affect macrophage phenotype and function, including how they hunt for particles and pathogens, as well as the implications for phagocytosis, autophagy, and polarization from proinflammatory to prohealing phenotype. We further discuss how this knowledge can be harnessed in regenerative medicine and for the design of new drugs and immune-modulatory drug delivery systems, biomaterials, and tissue scaffolds.
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Affiliation(s)
- Nikhil Jain
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, and Department of Health Sciences and Technology, ETH Zurich, CH-8093 Zurich, Switzerland;
| | - Jens Moeller
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, and Department of Health Sciences and Technology, ETH Zurich, CH-8093 Zurich, Switzerland;
| | - Viola Vogel
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, and Department of Health Sciences and Technology, ETH Zurich, CH-8093 Zurich, Switzerland;
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16
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Gagné D, Benoit YD, Groulx JF, Vachon PH, Beaulieu JF. ILK supports RhoA/ROCK-mediated contractility of human intestinal epithelial crypt cells by inducing the fibrillogenesis of endogenous soluble fibronectin during the spreading process. BMC Mol Cell Biol 2020; 21:14. [PMID: 32183701 PMCID: PMC7079544 DOI: 10.1186/s12860-020-00259-0] [Citation(s) in RCA: 9] [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: 11/13/2019] [Accepted: 03/05/2020] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Fibronectin (FN) assembly into an insoluble fibrillar matrix is a crucial step in many cell responses to extracellular matrix (ECM) properties, especially with regards to the integrin-related mechanosensitive signaling pathway. We have previously reported that the silencing of expression of integrin-linked kinase (ILK) in human intestinal epithelial crypt (HIEC) cells causes significant reductions in proliferation and spreading through concomitantly acquired impairment of soluble FN deposition. These defects in ILK-depleted cells are rescued by growth on exogenous FN. In the present study we investigated the contribution of ILK in the fibrillogenesis of FN and its relation to integrin-actin axis signaling and organization. RESULTS We show that de novo fibrillogenesis of endogenous soluble FN is ILK-dependent. This function seemingly induces the assembly of an ECM that supports increased cytoskeletal tension and the development of a fully spread contractile cell phenotype. We observed that HIEC cell adhesion to exogenous FN or collagen-I (Col-I) is sufficient to restore fibrillogenesis of endogenous FN in ILK-depleted cells. We also found that optimal engagement of the Ras homolog gene family member A (RhoA) GTPase/Rho-associated kinase (ROCK-1, ROCK-2)/myosin light chain (MLC) pathway, actin ventral stress fiber formation, and integrin adhesion complex (IAC) maturation rely primarily upon the cell's capacity to execute FN fibrillogenesis, independent of any significant ILK input. Lastly, we confirm the integrin α5β1 as the main integrin responsible for FN assembly, although in ILK-depleted cells αV-class integrins expression is needed to allow the rescue of FN fibrillogenesis on exogenous substrate. CONCLUSION Our study demonstrates that ILK specifically induces the initiation of FN fibrillogenesis during cell spreading, which promotes RhoA/ROCK-dependent cell contractility and maturation of the integrin-actin axis structures. However, the fibrillogenesis process and its downstream effect on RhoA signaling, cell contractility and spreading are ILK-independent in human intestinal epithelial crypt cells.
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Affiliation(s)
- David Gagné
- Laboratory of Intestinal Physiopathology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, and Research Center of the Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, J1H 5N4 Canada
| | - Yannick D. Benoit
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5 Canada
| | - Jean-François Groulx
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California San Diego, La Jolla, California, 92093 USA
| | - Pierre H. Vachon
- Department of Anatomy and Cell Biology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, Québec, J1H 5N4 Canada
| | - Jean-François Beaulieu
- Laboratory of Intestinal Physiopathology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, and Research Center of the Centre Hospitalier Universitaire de Sherbrooke, Sherbrooke, QC, J1H 5N4 Canada
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17
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Filla MS, Faralli JA, Desikan H, Peotter JL, Wannow AC, Peters DM. Activation of αvβ3 Integrin Alters Fibronectin Fibril Formation in Human Trabecular Meshwork Cells in a ROCK-Independent Manner. Invest Ophthalmol Vis Sci 2020; 60:3897-3913. [PMID: 31529121 PMCID: PMC6750892 DOI: 10.1167/iovs.19-27171] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Purpose Fibronectin fibrillogenesis is an integrin-mediated process that may contribute to the pathogenesis of primary open-angle glaucoma (POAG). Here, we examined the effects of αvβ3 integrins on fibrillogenesis in immortalized TM-1 cells and human trabecular meshwork (HTM) cells. Methods TM-1 cells overexpressing wild-type β3 (WTβ3) or constitutively active β3 (CAβ3) integrin subunits were generated. Control cells were transduced with an empty vector (EV). Deoxycholic acid (DOC) extraction of monolayers, immunofluorescence microscopy, and On-cell western analyses were used to determine levels of fibronectin fibrillogenesis and fibronectin fibril composition (EDA+ and EDB+ fibronectins) and conformation. αvβ3 and α5β1 Integrin levels were determined using fluorescence-activated cell sorting (FACS). Cilengitide and an adenovirus vector expressing WTβ3 or CAβ3 integrin subunits were used to examine the role of αvβ3 integrin in HTM cells. The role of the canonical α5β1 integrin–mediated pathway in fibrillogenesis was determined using the fibronectin-binding peptide FUD, the β1 integrin function-blocking antibody 13, and the Rho kinase (ROCK) inhibitor Y27632. Results Activation of αvβ3 integrin enhanced the assembly of fibronectin into DOC-insoluble fibrils in both TM-1 and HTM cells. The formation of fibronectin fibrils was dependent on α5β1 integrin and could be inhibited by FUD. However, fibrillogenesis was unaffected by Y27632. Fibrils assembled by CAβ3 cells also contained high levels of EDA+ and EDB+ fibronectin and fibronectin that was stretched. Conclusions αvβ3 Integrin signaling altered the deposition and structure of fibronectin fibrils using a β1 integrin/ROCK-independent mechanism. Thus, αvβ3 integrins could play a significant role in altering the function of fibronectin matrices in POAG.
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Affiliation(s)
- Mark S Filla
- Departments of Pathology & Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Jennifer A Faralli
- Departments of Pathology & Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Harini Desikan
- Departments of Pathology & Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Jennifer L Peotter
- Departments of Pathology & Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Abigail C Wannow
- Departments of Pathology & Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States
| | - Donna M Peters
- Departments of Pathology & Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States.,Department of Ophthalmology and Visual Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States
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18
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Profile of Matrix-Remodeling Proteinases in Osteoarthritis: Impact of Fibronectin. Cells 2019; 9:cells9010040. [PMID: 31877874 PMCID: PMC7017325 DOI: 10.3390/cells9010040] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 12/16/2019] [Accepted: 12/18/2019] [Indexed: 12/11/2022] Open
Abstract
The extracellular matrix (ECM) is a complex and specialized three-dimensional macromolecular network, present in nearly all tissues, that also interacts with cell surface receptors on joint resident cells. Changes in the composition and physical properties of the ECM lead to the development of many diseases, including osteoarthritis (OA). OA is a chronic degenerative rheumatic disease characterized by a progressive loss of synovial joint function as a consequence of the degradation of articular cartilage, also associated with alterations in the synovial membrane and subchondral bone. During OA, ECM-degrading enzymes, including urokinase-type plasminogen activator (uPA), matrix metalloproteinases (MMPs), and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs), cleave ECM components, such as fibronectin (Fn), generating fibronectin fragments (Fn-fs) with catabolic properties. In turn, Fn-fs promote activation of these proteinases, establishing a degradative and inflammatory feedback loop. Thus, the aim of this review is to update the contribution of ECM-degrading proteinases to the physiopathology of OA as well as their modulation by Fn-fs.
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19
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Taki M, Yamashita T, Yatabe K, Vogel V. Mechano-chromic protein-polymer hybrid hydrogel to visualize mechanical strain. SOFT MATTER 2019; 15:9388-9393. [PMID: 31609367 DOI: 10.1039/c9sm00380k] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In a proof-of-concept study, a mechano-chromic hydrogel was synthesized here, via chemoenzymatic click conjugation of fluorophore-labeled fibronectin into a synthetic hydrogel co-polymers (i.e., poly-N-isopropylacrylamide/polyethylene glycol). The optical FRET response could be tuned by macroscopic stretch.
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Affiliation(s)
- Masumi Taki
- Laboratory of Applied Mechanobiology, Department of Health Sciences and Technology, ETH Zürich, Vladimir-Prelog-Weg 4, 8093 Zürich, Switzerland.
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20
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Faralli JA, Filla MS, Peters DM. Role of Fibronectin in Primary Open Angle Glaucoma. Cells 2019; 8:E1518. [PMID: 31779192 PMCID: PMC6953041 DOI: 10.3390/cells8121518] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Revised: 11/22/2019] [Accepted: 11/24/2019] [Indexed: 01/08/2023] Open
Abstract
Primary open angle glaucoma (POAG) is the most common form of glaucoma and the 2nd most common cause of irreversible vision loss in the United States. Nearly 67 million people have the disease worldwide including >3 million in the United States. A major risk factor for POAG is an elevation in intraocular pressure (IOP). The increase in IOP is believed to be caused by an increase in the deposition of extracellular matrix proteins, in particular fibronectin, in a region of the eye known as the trabecular meshwork (TM). How fibronectin contributes to the increase in IOP is not well understood. The increased density of fibronectin fibrils is thought to increase IOP by altering the compliance of the trabecular meshwork. Recent studies, however, also suggest that the composition and organization of fibronectin fibrils would affect IOP by changing the cell-matrix signaling events that control the functional properties of the cells in the trabecular meshwork. In this article, we will discuss how changes in the properties of fibronectin and fibronectin fibrils could contribute to the regulation of IOP.
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Affiliation(s)
- Jennifer A. Faralli
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, USA; (J.A.F.); (M.S.F.)
| | - Mark S. Filla
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, USA; (J.A.F.); (M.S.F.)
| | - Donna M. Peters
- Departments of Pathology & Laboratory Medicine, University of Wisconsin, Madison, WI 53706, USA; (J.A.F.); (M.S.F.)
- Ophthalmology & Visual Sciences, University of Wisconsin, Madison, WI 53706, USA
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21
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Graham J, Raghunath M, Vogel V. Fibrillar fibronectin plays a key role as nucleator of collagen I polymerization during macromolecular crowding-enhanced matrix assembly. Biomater Sci 2019; 7:4519-4535. [PMID: 31436263 PMCID: PMC6810780 DOI: 10.1039/c9bm00868c] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Macromolecular crowding is used by tissue engineers to accelerate extracellular matrix assembly in vitro, however, most mechanistic studies focus on the impact of crowding on collagen fiber assembly and largely ignore the highly abundant provisional matrix protein fibronectin. We show that the accelerated collagen I assembly as induced by the neutral crowding molecule Ficoll is regulated by cell access to fibronectin. Ficoll treatment leads to significant increases in the amount of surface adherent fibronectin, which can readily be harvested by cells to speed up fibrillogenesis. FRET studies reveal that Ficoll crowding also upregulates the total amount of fibronectin fibers in a low-tension state through upregulating fibronectin assembly. Since un-stretched fibronectin fibers have more collagen binding sites to nucleate the onset of collagen fibrillogenesis, our data suggest that the Ficoll-induced upregulation of low-tension fibronectin fibers contributes to enhanced collagen assembly in crowded conditions. In contrast, chemical cross-linking of fibronectin to the glass substrate prior to cell seeding prevents early force mediated fibronectin harvesting from the substrate and suppresses upregulation of collagen I assembly in the presence of Ficoll, even though the crowded environment is known to drive enzymatic cleavage of procollagen and collagen fiber formation. To show that our findings can be exploited for tissue engineering applications, we demonstrate that the addition of supplemental fibronectin in the form of an adsorbed coating markedly improves the speed of tissue formation under crowding conditions.
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Affiliation(s)
- Jenna Graham
- Department of Health Sciences and Technology, ETH Zürich, CH-8093 Zürich, Switzerland.
| | - Michael Raghunath
- ZHAW School of Life Sciences and Facility Management, Institute for Chemistry and Biotechnology, Center for Cell Biology and Tissue Engineering, CH-8820 Wädenswil, Switzerland
| | - Viola Vogel
- Department of Health Sciences and Technology, ETH Zürich, CH-8093 Zürich, Switzerland.
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22
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Paten JA, Martin CL, Wanis JT, Siadat SM, Figueroa-Navedo AM, Ruberti JW, Deravi LF. Molecular Interactions between Collagen and Fibronectin: A Reciprocal Relationship that Regulates De Novo Fibrillogenesis. Chem 2019. [DOI: 10.1016/j.chempr.2019.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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23
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Abstract
Cells need to be anchored to extracellular matrix (ECM) to survive, yet the role of ECM in guiding developmental processes, tissue homeostasis, and aging has long been underestimated. How ECM orchestrates the deterioration of healthy to pathological tissues, including fibrosis and cancer, also remains poorly understood. Inquiring how alterations in ECM fiber tension might drive these processes is timely, as mechanobiology is a rapidly growing field, and many novel mechanisms behind the mechanical forces that can regulate protein, cell, and tissue functions have recently been deciphered. The goal of this article is to review how forces can switch protein functions, and thus cell signaling, and thereby inspire new approaches to exploit the mechanobiology of ECM in regenerative medicine as well as for diagnostic and therapeutic applications. Some of the mechanochemical switching concepts described here for ECM proteins are more general and apply to intracellular proteins as well.
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Affiliation(s)
- Viola Vogel
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department for Health Sciences and Technology, ETH Zürich, CH-8093 Zürich, Switzerland;
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24
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Bradshaw MJ, Hoffmann GA, Wong JY, Smith ML. Fibronectin fiber creep under constant force loading. Acta Biomater 2019; 88:78-85. [PMID: 30780000 DOI: 10.1016/j.actbio.2019.02.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 02/06/2019] [Accepted: 02/15/2019] [Indexed: 12/12/2022]
Abstract
Viscoelasticity is a fundamental property of virtually all biological materials, and proteinaceous, fibrous materials that constitute the extracellular matrix (ECM) are no exception. Viscoelasticity may be particularly important in the ECM since cells can apply mechanical stress resulting from cell contractility over very long periods of time. However, measurements of ECM fiber response to long-term constant force loading are scarce, despite the increasing recognition that mechanical strain regulates the biological function of some ECM fibers. We developed a dual micropipette system that applies constant force to single fibers for up to 8 h. We utilized this system to study the time dependent response of fibronectin (Fn) fibers to constant force, as Fn fibers exhibit tremendous extensibility before mechanical failure as well as strain dependent alterations in biological properties. These data demonstrate the Fn fibers continue to stretch under constant force loading for at least 8 h and that this long-term creep results in plastic deformation of Fn fibers, in contrast to elastic deformation of Fn fibers under short-term, but fast loading rate extension. These data demonstrate that physiologically-relevant loading may impart mechanical features to Fn fibers by switching them into an extended state that may have altered biological functions. STATEMENT OF SIGNIFICANCE: Measurements of extracellular matrix (ECM) fiber response to constant force loading are scarce, so we developed a novel technique for applying constant force to single ECM fibers. We used this technique to measure constant force creep of fibronectin fibers since these fibers have been shown to be mechanotransducers whose functions can be altered by mechanical strain. We found that fibronectin fibers creep under constant force loading for the duration of the experiment and that this creep behavior resembles a power law. Furthermore, we found that constant force creep results in plastic deformation of the fibers, which suggests that the mechanobiological switching of fibronectin can only occur once after long-term loading.
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Affiliation(s)
- Mark J Bradshaw
- Department of Mechanical Engineering, Boston University, Boston, MA 02215, United States
| | - Gwendolyn A Hoffmann
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, United States
| | - Joyce Y Wong
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, United States
| | - Michael L Smith
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, United States.
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Muncie JM, Weaver VM. The Physical and Biochemical Properties of the Extracellular Matrix Regulate Cell Fate. Curr Top Dev Biol 2018; 130:1-37. [PMID: 29853174 DOI: 10.1016/bs.ctdb.2018.02.002] [Citation(s) in RCA: 149] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The extracellular matrix is a complex network of hydrated macromolecular proteins and sugars that, in concert with bound soluble factors, comprise the acellular stromal microenvironment of tissues. Rather than merely providing structural information to cells, the extracellular matrix plays an instructive role in development and is critical for the maintenance of tissue homeostasis. In this chapter, we review the composition of the extracellular matrix and summarize data illustrating its importance in embryogenesis, tissue-specific development, and stem cell differentiation. We discuss how the biophysical and biochemical properties of the extracellular matrix ligate specific transmembrane receptors to activate intracellular signaling that alter cell shape and cytoskeletal dynamics to modulate cell growth and viability, and direct cell migration and cell fate. We present examples describing how the extracellular matrix functions as a highly complex physical and chemical entity that regulates tissue organization and cell behavior through a dynamic and reciprocal dialogue with the cellular constituents of the tissue. We suggest that the extracellular matrix not only transmits cellular and tissue-level force to shape development and tune cellular activities that are key for coordinated tissue behavior, but that it is itself remodeled such that it temporally evolves to maintain the integrated function of the tissue. Accordingly, we argue that perturbations in extracellular matrix composition and structure compromise key developmental events and tissue homeostasis, and promote disease.
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Affiliation(s)
- Jonathon M Muncie
- Center for Bioengineering and Tissue Regeneration, University of California, San Francisco, CA, United States; Graduate Program in Bioengineering, University of California San Francisco and University of California Berkeley, San Francisco, CA, United States
| | - Valerie M Weaver
- Center for Bioengineering and Tissue Regeneration, University of California, San Francisco, CA, United States; Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, The Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, CA, United States.
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26
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Pyne A, Kundu S, Banerjee P, Sarkar N. Unveiling the Aggregation Behavior of Doxorubicin Hydrochloride in Aqueous Solution of 1-Octyl-3-methylimidazolium Chloride and the Effect of Bile Salt on These Aggregates: A Microscopic Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:3296-3306. [PMID: 29474788 DOI: 10.1021/acs.langmuir.8b00029] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this article, we have unveiled the aggregation behavior of a potent chemotherapeutic drug, doxorubicin hydrochloride (Dox) in a well-known imidazolium based surface active ionic liquid (SAIL), 1-octyl-3-methylimidazolium chloride (C8mimCl). The aggregates formed by Dox in C8mimCl have been characterized using dynamic light scattering (DLS), fluorescence lifetime imaging microscopy (FLIM), high-resolution transmission electron microscopy (HR-TEM), analytical transmission electron microscopy (analytical TEM), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and Fourier-transform infrared spectroscopy (FTIR) measurements. It is found that Dox forms large spherical aggregates in the presence of C8mimCl SAIL. We have also explored the driving force behind this aggregation behavior of Dox in C8mimCl. Furthermore, it is observed that in the presence of a common bile salt, sodium cholate (NaCh), Dox/C8mimCl spherical aggregates disrupt to form rodlike fibrillar aggregates. Therefore, formation of spherical aggregates and also its disruption into rodlike fibrillar aggregates have been performed, and this is expected to open a new scope for the design of a new generation smart drug delivery system where the drug itself aggregates to form the delivery system.
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Affiliation(s)
- Arghajit Pyne
- Department of Chemistry , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
| | - Sangita Kundu
- Department of Chemistry , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
| | - Pavel Banerjee
- Department of Chemistry , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
| | - Nilmoni Sarkar
- Department of Chemistry , Indian Institute of Technology , Kharagpur 721302 , West Bengal , India
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Chantre CO, Campbell PH, Golecki HM, Buganza AT, Capulli AK, Deravi LF, Dauth S, Sheehy SP, Paten JA, Gledhill K, Doucet YS, Abaci HE, Ahn S, Pope BD, Ruberti JW, Hoerstrup SP, Christiano AM, Parker KK. Production-scale fibronectin nanofibers promote wound closure and tissue repair in a dermal mouse model. Biomaterials 2018; 166:96-108. [PMID: 29549768 DOI: 10.1016/j.biomaterials.2018.03.006] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 03/01/2018] [Accepted: 03/03/2018] [Indexed: 11/29/2022]
Abstract
Wounds in the fetus can heal without scarring. Consequently, biomaterials that attempt to recapitulate the biophysical and biochemical properties of fetal skin have emerged as promising pro-regenerative strategies. The extracellular matrix (ECM) protein fibronectin (Fn) in particular is believed to play a crucial role in directing this regenerative phenotype. Accordingly, Fn has been implicated in numerous wound healing studies, yet remains untested in its fibrillar conformation as found in fetal skin. Here, we show that high extensional (∼1.2 ×105 s-1) and shear (∼3 ×105 s-1) strain rates in rotary jet spinning (RJS) can drive high throughput Fn fibrillogenesis (∼10 mL/min), thus producing nanofiber scaffolds that are used to effectively enhance wound healing. When tested on a full-thickness wound mouse model, Fn nanofiber dressings not only accelerated wound closure, but also significantly improved tissue restoration, recovering dermal and epidermal structures as well as skin appendages and adipose tissue. Together, these results suggest that bioprotein nanofiber fabrication via RJS could set a new paradigm for enhancing wound healing and may thus find use in a variety of regenerative medicine applications.
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Affiliation(s)
- Christophe O Chantre
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA; Institute for Regenerative Medicine, University of Zurich, ZH, Switzerland
| | - Patrick H Campbell
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Holly M Golecki
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Adrian T Buganza
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA; Department of Mechanical Engineering, Purdue University, West Lafayette, IL, USA
| | - Andrew K Capulli
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Leila F Deravi
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA; Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA, USA
| | - Stephanie Dauth
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Sean P Sheehy
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Jeffrey A Paten
- Department of Bioengineering, Northeastern University, Boston, MA, UK
| | - Karl Gledhill
- Department of Dermatology, Columbia University, New York, NY, USA
| | - Yanne S Doucet
- Department of Dermatology, Columbia University, New York, NY, USA
| | - Hasan E Abaci
- Department of Dermatology, Columbia University, New York, NY, USA
| | - Seungkuk Ahn
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
| | - Benjamin D Pope
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA; Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Jeffrey W Ruberti
- Department of Bioengineering, Northeastern University, Boston, MA, UK
| | - Simon P Hoerstrup
- Institute for Regenerative Medicine, University of Zurich, ZH, Switzerland
| | | | - Kevin Kit Parker
- Disease Biophysics Group, Wyss Institute for Biologically Inspired Engineering, John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
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28
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Imaging mechanotransduction: Seeing forces from molecules to cells. CURRENT OPINION IN BIOMEDICAL ENGINEERING 2018. [DOI: 10.1016/j.cobme.2018.01.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Raoufi M, Hajipour MJ, Kamali Shahri SM, Schoen I, Linn U, Mahmoudi M. Probing fibronectin conformation on a protein corona layer around nanoparticles. NANOSCALE 2018; 10:1228-1233. [PMID: 29292453 DOI: 10.1039/c7nr06970g] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Protein unfolding induced by nanoparticles (NPs) can lead to exposure of cryptic epitopes that might dictate biological identity and affect NP biological fate (e.g., blood circulation time, biodistribution, and tumor accumulation). Here, we monitor the conformation of fluorescence resonance energy transfer (FRET)-labelled fibronectin (FN) on corona-coated gold NPs. We found that the labelled FN proteins, which directly accessed the gold NP surface, underwent more pronounced conformational changes than those associated with the protein corona via protein-protein interactions. FRET and liquid chromatography-mass spectrometry analyses demonstrated that NP size/concentration, pH change, and the level of surface coverage by the corona can tune the accessibility of labelled FN to the gold NP surface. Although some subsequently adsorbing proteins accessed the NP surface thanks to incomplete surface coverage and protein exchange (the Vroman effect), most outer-layer proteins could not directly bind to the NP surface, blocked by pre-adsorbed corona layers. This finding was also partially confirmed by isothermal titration calorimetry (ITC) analysis. These results suggest the proof-of-concept that outermost-layer proteins with modestly changed conformation rather than unfolded proteins at the gold NP surface effectively create the NPs' biological identity, which might have important implications on biological fates of gold NPs.
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Affiliation(s)
- Mohammad Raoufi
- Nanotechnology Research Centre, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 1417614411, Iran
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Ortiz Franyuti D, Mitsi M, Vogel V. Mechanical Stretching of Fibronectin Fibers Upregulates Binding of Interleukin-7. NANO LETTERS 2018; 18:15-25. [PMID: 28845674 DOI: 10.1021/acs.nanolett.7b01617] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Since evidence is rising that extracellular matrix (ECM) fibers might serve as reservoirs for growth factors and cytokines, we investigated the interaction between fibronectin (FN) and interleukin-7 (IL-7), a cytokine of immunological significance and a target of several immunotherapies. By employing a FN fiber stretch assay and Förster resonance energy transfer (FRET) confocal microscopy, we found that stretching of FN fibers increased IL-7 binding. We localized the FN binding site on the CD loop of IL-7, since a synthetic CD loop peptide also bound stronger to stretched than to relaxed FN fibers. On the basis of a structural model, we propose that the CD loop can bind to FN, while IL-7 is bound to its cognate cell surface receptors. Sequence alignment with bacterial adhesins, which also bind the FN N-terminus, suggests that a conserved motif on the CD loop (110TKSLEEN116 and the truncated 112SLEE115 in human and mouse IL-7, respectively) might bind to the second FN type I module (FnI2) and that additional epitopes enhance the stretch-upregulated binding. FN fiber stretching might thus serve as a mechano-regulated mechanism to locally concentrate IL-7 in an ECM-bound state, thereby upregulating the potency of IL-7 signaling. A feedback model mechanism is proposed that could explain the well-known, but poorly understood, function of IL-7 in ECM homeostasis. Understanding how local IL-7 availability and signaling might be modulated by the tensional state of the ECM niche, which is adjusted by residing stroma cells, is highly relevant for basic science but also for advancing IL-7 based immunotherapies.
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Affiliation(s)
- Daniela Ortiz Franyuti
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department for Health Sciences and Technology (D-HEST), ETH Zurich , Vladimir-Prelog-Weg 4, HCI F443 CH-8093 Zürich, Switzerland
| | - Maria Mitsi
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department for Health Sciences and Technology (D-HEST), ETH Zurich , Vladimir-Prelog-Weg 4, HCI F443 CH-8093 Zürich, Switzerland
| | - Viola Vogel
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department for Health Sciences and Technology (D-HEST), ETH Zurich , Vladimir-Prelog-Weg 4, HCI F443 CH-8093 Zürich, Switzerland
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32
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Kollmannsberger P, Bidan CM, Dunlop JWC, Fratzl P, Vogel V. Tensile forces drive a reversible fibroblast-to-myofibroblast transition during tissue growth in engineered clefts. SCIENCE ADVANCES 2018; 4:eaao4881. [PMID: 29349300 PMCID: PMC5771696 DOI: 10.1126/sciadv.aao4881] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 12/11/2017] [Indexed: 05/23/2023]
Abstract
Myofibroblasts orchestrate wound healing processes, and if they remain activated, they drive disease progression such as fibrosis and cancer. Besides growth factor signaling, the local extracellular matrix (ECM) and its mechanical properties are central regulators of these processes. It remains unknown whether transforming growth factor-β (TGF-β) and tensile forces work synergistically in up-regulating the transition of fibroblasts into myofibroblasts and whether myofibroblasts undergo apoptosis or become deactivated by other means once tissue homeostasis is reached. We used three-dimensional microtissues grown in vitro from fibroblasts in macroscopically engineered clefts for several weeks and found that fibroblasts transitioned into myofibroblasts at the highly tensed growth front as the microtissue progressively closed the cleft, in analogy to closing a wound site. Proliferation was up-regulated at the growth front, and new highly stretched fibronectin fibers were deposited, as revealed by fibronectin fluorescence resonance energy transfer probes. As the tissue was growing, the ECM underneath matured into a collagen-rich tissue containing mostly fibroblasts instead of myofibroblasts, and the fibronectin fibers were under reduced tension. This correlated with a progressive rounding of cells from the growth front inward, with decreased α-smooth muscle actin expression, YAP nuclear translocation, and cell proliferation. Together, this suggests that the myofibroblast phenotype is stabilized at the growth front by tensile forces, even in the absence of endogenously supplemented TGF-β, and reverts into a quiescent fibroblast phenotype already 10 μm behind the growth front, thus giving rise to a myofibroblast-to-fibroblast transition. This is the hallmark of reaching prohealing homeostasis.
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Affiliation(s)
- Philip Kollmannsberger
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Science and Technology, ETH (Eidgenössische Technische Hochschule) Zurich, Zurich, Switzerland
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Golm, Germany
| | - Cécile M. Bidan
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Golm, Germany
- Université Grenoble Alpes, CNRS, Laboratoire Interdisciplinaire de Physique, 38000 Grenoble, France
| | - John W. C. Dunlop
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Golm, Germany
| | - Peter Fratzl
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, Golm, Germany
| | - Viola Vogel
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Science and Technology, ETH (Eidgenössische Technische Hochschule) Zurich, Zurich, Switzerland
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33
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Arnoldini S, Moscaroli A, Chabria M, Hilbert M, Hertig S, Schibli R, Béhé M, Vogel V. Novel peptide probes to assess the tensional state of fibronectin fibers in cancer. Nat Commun 2017; 8:1793. [PMID: 29176724 PMCID: PMC5702617 DOI: 10.1038/s41467-017-01846-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Accepted: 10/19/2017] [Indexed: 01/16/2023] Open
Abstract
Transformations of extracellular matrix (ECM) accompany pathological tissue changes, yet how cell-ECM crosstalk drives these processes remains unknown as adequate tools to probe forces or mechanical strains in tissues are lacking. Here, we introduce a new nanoprobe to assess the mechanical strain of fibronectin (Fn) fibers in tissue, based on the bacterial Fn-binding peptide FnBPA5. FnBPA5 exhibits nM binding affinity to relaxed, but not stretched Fn fibers and is shown to exhibit strain-sensitive ECM binding in cell culture in a comparison with an established Fn-FRET probe. Staining of tumor tissue cryosections shows large regions of relaxed Fn fibers and injection of radiolabeled 111In-FnBPA5 in a prostate cancer mouse model reveals specific accumulation of 111In-FnBPA5 in tumor with prolonged retention compared to other organs. The herein presented approach enables to investigate how Fn fiber strain at the tissue level impacts cell signaling and pathological progression in different diseases.
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Affiliation(s)
- Simon Arnoldini
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Sciences and Technology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093, Zurich, Switzerland
| | - Alessandra Moscaroli
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, OIPA/103, 5232, Villigen PSI, Switzerland
| | - Mamta Chabria
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Sciences and Technology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093, Zurich, Switzerland
| | - Manuel Hilbert
- Laboratory of Biomolecular Research, Paul Scherrer Institute, OFLC/102, 5232, Villigen PSI, Switzerland
| | - Samuel Hertig
- Hertig Visualizations, Technikumstrasse 10B, 3400, Burgdorf, Switzerland
| | - Roger Schibli
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, OIPA/103, 5232, Villigen PSI, Switzerland.,Institute for Pharamaceutical Science, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 4, 8093, Zurich, Switzerland
| | - Martin Béhé
- Center for Radiopharmaceutical Sciences, Paul Scherrer Institute, OIPA/103, 5232, Villigen PSI, Switzerland.
| | - Viola Vogel
- Laboratory of Applied Mechanobiology, Institute of Translational Medicine, Department of Health Sciences and Technology, ETH Zurich, Vladimir-Prelog-Weg 4, 8093, Zurich, Switzerland.
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Bidan CM, Kollmannsberger P, Gering V, Ehrig S, Joly P, Petersen A, Vogel V, Fratzl P, Dunlop JWC. Gradual conversion of cellular stress patterns into pre-stressed matrix architecture during in vitro tissue growth. J R Soc Interface 2017; 13:rsif.2016.0136. [PMID: 27194484 DOI: 10.1098/rsif.2016.0136] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 04/22/2016] [Indexed: 12/14/2022] Open
Abstract
The complex arrangement of the extracellular matrix (ECM) produced by cells during tissue growth, healing and remodelling is fundamental to tissue function. In connective tissues, it is still unclear how both cells and the ECM become and remain organized over length scales much larger than the distance between neighbouring cells. While cytoskeletal forces are essential for assembly and organization of the early ECM, how these processes lead to a highly organized ECM in tissues such as osteoid is not clear. To clarify the role of cellular tension for the development of these ordered fibril architectures, we used an in vitro model system, where pre-osteoblastic cells produced ECM-rich tissue inside channels with millimetre-sized triangular cross sections in ceramic scaffolds. Our results suggest a mechanical handshake between actively contracting cells and ECM fibrils: the build-up of a long-range organization of cells and the ECM enables a gradual conversion of cell-generated tension to pre-straining the ECM fibrils, which reduces the work cells have to generate to keep mature tissue under tension.
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Affiliation(s)
- Cécile M Bidan
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany Berlin-Brandenburg Center and School for Regenerative Therapies, Julius Wolff Institute, Charité-Universitätsmedizin, Berlin, Germany University Grenoble Alpes, LIPhy, 38000 Grenoble, France CNRS, LIPhy, 38000 Grenoble, France
| | - Philip Kollmannsberger
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany Laboratory of Applied Mechanobiology, Department of Health Sciences and Technology (D-HEST), ETH Zürich, Switzerland
| | - Vanessa Gering
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany
| | - Sebastian Ehrig
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany
| | - Pascal Joly
- Berlin-Brandenburg Center and School for Regenerative Therapies, Julius Wolff Institute, Charité-Universitätsmedizin, Berlin, Germany Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA
| | - Ansgar Petersen
- Berlin-Brandenburg Center and School for Regenerative Therapies, Julius Wolff Institute, Charité-Universitätsmedizin, Berlin, Germany
| | - Viola Vogel
- Laboratory of Applied Mechanobiology, Department of Health Sciences and Technology (D-HEST), ETH Zürich, Switzerland
| | - Peter Fratzl
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany
| | - John W C Dunlop
- Department of Biomaterials, Max Planck Institute of Colloids and Interfaces, 14424 Potsdam, Germany
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Sato Y, Nagatoshi K, Hamano A, Imamura Y, Huss D, Uchida S, Lansford R. Basal filopodia and vascular mechanical stress organize fibronectin into pillars bridging the mesoderm-endoderm gap. Development 2017; 144:281-291. [PMID: 28096216 DOI: 10.1242/dev.141259] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Accepted: 11/29/2016] [Indexed: 12/23/2022]
Abstract
Cells may exchange information with other cells and tissues by exerting forces on the extracellular matrix (ECM). Fibronectin (FN) is an important ECM component that forms fibrils through cell contacts and creates directionally biased geometry. Here, we demonstrate that FN is deposited as pillars between widely separated germ layers, namely the somitic mesoderm and the endoderm, in quail embryos. Alongside the FN pillars, long filopodia protrude from the basal surfaces of somite epithelial cells. Loss-of-function of Ena/VASP, α5β1-integrins or talin in the somitic cells abolished the FN pillars, indicating that FN pillar formation is dependent on the basal filopodia through these molecules. The basal filopodia and FN pillars are also necessary for proper somite morphogenesis. We identified a new mechanism contributing to FN pillar formation by focusing on cyclic expansion of adjacent dorsal aorta. Maintenance of the directional alignment of the FN pillars depends on pulsatile blood flow through the dorsal aortae. These results suggest that the FN pillars are specifically established through filopodia-mediated and pulsating force-related mechanisms.
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Affiliation(s)
- Yuki Sato
- Department of Anatomy and Cell Biology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan .,JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Kei Nagatoshi
- Department of Anatomy and Cell Biology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
| | - Ayumi Hamano
- Department of Advanced Information Technology, Faculty of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0385, Japan
| | - Yuko Imamura
- Graduate School of Science, Kumamoto University, 2-39-1 Kurokami, Chuo-ku, Kumamoto 860-8555, Japan
| | - David Huss
- Department of Radiology and Developmental Neuroscience Program, Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, CA 90027, USA.,Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Seiichi Uchida
- Department of Advanced Information Technology, Faculty of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0385, Japan
| | - Rusty Lansford
- Department of Radiology and Developmental Neuroscience Program, Saban Research Institute, Children's Hospital Los Angeles, Los Angeles, CA 90027, USA.,Department of Radiology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
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36
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Fibronectin, the extracellular glue. Matrix Biol 2017; 60-61:27-37. [DOI: 10.1016/j.matbio.2016.07.011] [Citation(s) in RCA: 180] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Revised: 07/22/2016] [Accepted: 07/30/2016] [Indexed: 12/13/2022]
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Grigoriou E, Cantini M, Dalby MJ, Petersen A, Salmeron-Sanchez M. Cell migration on material-driven fibronectin microenvironments. Biomater Sci 2017; 5:1326-1333. [PMID: 28612879 PMCID: PMC5858633 DOI: 10.1039/c7bm00333a] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Accepted: 06/06/2017] [Indexed: 12/15/2022]
Abstract
Cell migration is a fundamental process involved in a wide range of biological phenomena. However, how the underlying mechanisms that control migration are orchestrated is not fully understood. In this work, we explore the migratory characteristics of human fibroblasts using different organisations of fibronectin (FN) triggered by two chemically similar surfaces, poly(ethyl acrylate) (PEA) and poly(methyl acrylate) (PMA); cell migration is mediated via an intermediate layer of fibronectin (FN). FN is organised into nanonetworks upon simple adsorption on PEA whereas a globular conformation is observed on PMA. We studied cell speed over the course of 24 h and the morphology of focal adhesions in terms of area and length. Additionally, we analysed the amount of cell-secreted FN as well as FN remodelling. Velocity of human fibroblasts was found to exhibit a biphasic behaviour on PEA, whereas it remained fairly constant on PMA. FA analysis revealed more mature focal adhesions on PEA over time contrary to smaller FAs found on PMA. Finally, human fibroblasts seemed to remodel adsorbed FN more on PMA than on PEA. Overall, these results indicate that the cell-protein-material interface affects cell migratory behaviour. Analysis of FAs together with FN secretion and remodelling were associated with differences in cell velocity providing insights into the factors that can modulate cell motility.
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Affiliation(s)
- E. Grigoriou
- Division of Biomedical Engineering , School of Engineering , University of Glasgow , Glasgow , UK .
| | - M. Cantini
- Division of Biomedical Engineering , School of Engineering , University of Glasgow , Glasgow , UK .
| | - M. J. Dalby
- Centre for Cell Engineering , University of Glasgow , UK
| | - A. Petersen
- Berlin Brandenburg Center for Regenerative Therapies , Charité-Universitätsmedizin Berlin , Berlin , Germany .
| | - M. Salmeron-Sanchez
- Division of Biomedical Engineering , School of Engineering , University of Glasgow , Glasgow , UK .
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Fibronectin promotes directional persistence in fibroblast migration through interactions with both its cell-binding and heparin-binding domains. Sci Rep 2017. [PMID: 28623309 PMCID: PMC5473823 DOI: 10.1038/s41598-017-03701-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The precise mechanisms through which insoluble, cell-adhesive ligands induce and regulate directional cell migration remain obscure. We recently demonstrated that elevated surface density of physically adsorbed plasma fibronectin (FN) promotes high directional persistence in fibroblast migration. While cell-FN association through integrins α5β1 and αvβ3 was necessary, substrates that selectively engaged these integrins did not support the phenotype. We here show that high directional persistence necessitates a combination of the cell-binding and C-terminal heparin-binding domains of FN, but does not require the engagement of syndecan-4 or integrin α4β1. FN treatment with various fixation agents indicated that associated changes in fibroblast motility were due to biochemical changes, rather than alterations in its physical state. The nature of the coating determined the ability of fibroblasts to assemble endogenous or exogenous FN, while FN fibrillogenesis played a minor, but significant, role in regulating directionality. Interestingly, knockdown of cellular FN abolished cell motility altogether, demonstrating a requirement for intracellular processes in enabling fibroblast migration on FN. Lastly, kinase inhibition experiments revealed that regulation of cell speed and directional persistence are decoupled. Hence, we have identified factors that render full-length FN a promoter of directional migration and discuss the possible, relevant mechanisms.
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Wu F, Chen W, Gillis B, Fischbach C, Estroff LA, Gourdon D. Protein-crystal interface mediates cell adhesion and proangiogenic secretion. Biomaterials 2017; 116:174-185. [PMID: 27940370 PMCID: PMC5223748 DOI: 10.1016/j.biomaterials.2016.11.043] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/30/2016] [Accepted: 11/24/2016] [Indexed: 11/26/2022]
Abstract
The nanoscale materials properties of bone apatite crystals have been implicated in breast cancer bone metastasis and their interactions with extracellular matrix proteins are likely involved. In this study, we used geologic hydroxyapatite (HAP, Ca10(PO4)6(OH)2), closely related to bone apatite, to investigate how HAP surface chemistry and nano/microscale topography individually influence the crystal-protein interface, and how the altered protein deposition impacts subsequent breast cancer cell activities. We first utilized Förster resonance energy transfer (FRET) to assess the molecular conformation of fibronectin (Fn), a major extracellular matrix protein upregulated in cancer, when it adsorbed onto HAP facets. Our analysis reveals that both low surface charge density and nanoscale roughness of HAP facets individually contributed to molecular unfolding of Fn. We next quantified cell adhesion and secretion on Fn-coated HAP facets using MDA-MB-231 breast cancer cells. Our data show elevated proangiogenic and proinflammatory secretions associated with more unfolded Fn adsorbed onto nano-rough HAP facets with low surface charge density. These findings not only deconvolute the roles of crystal surface chemistry and topography in interfacial protein deposition but also enhance our knowledge of protein-mediated breast cancer cell interactions with apatite, which may be implicated in tumor growth and bone metastasis.
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Affiliation(s)
- Fei Wu
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA.
| | - Weisi Chen
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Brian Gillis
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Claudia Fischbach
- Nancy E. and Peter C. Meinig School of Biomedical Engineering, Cornell University, Ithaca, NY 14853, USA; Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY 14853, USA
| | - Lara A Estroff
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA; Kavli Institute at Cornell for Nanoscale Science, Ithaca, NY 14853, USA
| | - Delphine Gourdon
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14853, USA; Department of Physics, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
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Erickson HP. Protein unfolding under isometric tension-what force can integrins generate, and can it unfold FNIII domains? Curr Opin Struct Biol 2016; 42:98-105. [PMID: 28038331 DOI: 10.1016/j.sbi.2016.12.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 12/01/2016] [Accepted: 12/04/2016] [Indexed: 02/02/2023]
Abstract
Extracellular matrix fibrils of fibronectin (FN) are highly elastic, and are typically stretched three to four times their relaxed length. The mechanism of stretching has been controversial, in particular whether it involves tension-induced unfolding of FNIII domains. Recent studies have found that ∼5pN is the threshold isometric force for unfolding various protein domains. FNIII domains should therefore not be unfolded until the tension approaches 5pN. Integrins have been reported to generate forces ranging from 1 to >50pN, but I argue that studies reporting 1-2pN are the most convincing. This is not enough to unfold FNIII domains. Even if domains were unfolded, 2pN would only extend the worm-like-chain to about twice the length of the folded domain. Overall I conclude that stretching FN matrix fibrils involves primarily the compact to extended conformational change of FN dimers, with minimal contribution from unfolding FNIII domains.
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Affiliation(s)
- Harold P Erickson
- Department of Cell Biology, Duke University Medical Center, Durham, NC 27710, USA.
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41
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Sulfated hyaluronan alters fibronectin matrix assembly and promotes osteogenic differentiation of human bone marrow stromal cells. Sci Rep 2016; 6:36418. [PMID: 27808176 PMCID: PMC5093463 DOI: 10.1038/srep36418] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 10/14/2016] [Indexed: 02/04/2023] Open
Abstract
Extracellular matrix (ECM) composition and structural integrity is one of many factors that influence cellular differentiation. Fibronectin (FN) which is in many tissues the most abundant ECM protein forms a unique fibrillary network. FN homes several binding sites for sulfated glycosaminoglycans (sGAG), such as heparin (Hep), which was previously shown to influence FN conformation and protein binding. Synthetically sulfated hyaluronan derivatives (sHA) can serve as model molecules with a well characterized sulfation pattern to study sGAG-FN interaction. Here is shown that the low-sulfated sHA (sHA1) interacts with FN and influences fibril assembly. The interaction of FN fibrils with sHA1 and Hep, but not with non-sulfated HA was visualized by immunofluorescent co-staining. FRET analysis of FN confirmed the presence of more extended fibrils in human bone marrow stromal cells (hBMSC)-derived ECM in response to sHA1 and Hep. Although both sHA1 and Hep affected FN conformation, exclusively sHA1 increased FN protein level and led to thinner fibrils. Further, only sHA1 had a pro-osteogenic effect and enhanced the activity of tissue non-specific alkaline phosphatase. We hypothesize that the sHA1-triggered change in FN assembly influences the entire ECM network and could be the underlying mechanism for the pro-osteogenic effect of sHA1 on hBMSC.
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Cell sheet mechanics: How geometrical constraints induce the detachment of cell sheets from concave surfaces. Acta Biomater 2016; 45:85-97. [PMID: 27562610 DOI: 10.1016/j.actbio.2016.08.044] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 08/16/2016] [Accepted: 08/20/2016] [Indexed: 12/15/2022]
Abstract
Despite of the progress made to engineer structured microtissues such as BioMEMS and 3D bioprinting, little control exists how microtissues transform as they mature, as the misbalance between cell-generated forces and the strength of cell-cell and cell-substrate contacts can result in unintended tissue deformations and ruptures. To develop a quantitative perspective on how cellular contractility, scaffold curvature and cell-substrate adhesion control such rupture processes, human aortic smooth muscle cells were grown on glass substrates with submillimeter semichannels. We quantified cell sheet detachment from 3D confocal image stacks as a function of channel curvature and cell sheet tension by adding different amounts of Blebbistatin and TGF-β to inhibit or enhance cell contractility, respectively. We found that both higher curvature and higher contractility increased the detachment probability. Variations of the adhesive strength of the protein coating on the substrate revealed that the rupture plane was localized along the substrate-extracellular matrix interface for non-covalently adsorbed adhesion proteins, while the collagen-integrin interface ruptured when collagen I was covalently crosslinked to the substrate. Finally, a simple mechanical model is introduced that quantitatively explains how the tuning of substrate curvature, cell sheet contractility and adhesive strength can be used as tunable parameters as summarized in a first semi-quantitative phase diagram. These parameters can thus be exploited to either inhibit or purposefully induce a collective detachment of sheet-like microtissues for the use in tissue engineering and regenerative therapies. STATEMENT OF SIGNIFICANCE Despite of the significant progress in 3D tissue fabrication technologies at the microscale, there is still no quantitative model that can predict if cells seeded on a 3D structure maintain the imposed geometry while they form a continuous microtissue. Especially, detachment or loss of shape control of growing tissue is a major concern when designing 3D-structured scaffolds. Utilizing semi-cylindrical channels and vascular smooth muscle cells, we characterized how geometrical and mechanical parameters such as curvature of the substrate, cellular contractility, or protein-substrate adhesion strength tune the catastrophic detachment of microtissue. Observed results were rationalized by a theoretical model. The phase diagram showing how unintended tissue detachment progresses would help in designing of mechanically-balanced 3D scaffolds in future tissue engineering applications.
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Llopis-Hernández V, Cantini M, González-García C, Cheng ZA, Yang J, Tsimbouri PM, García AJ, Dalby MJ, Salmerón-Sánchez M. Material-driven fibronectin assembly for high-efficiency presentation of growth factors. SCIENCE ADVANCES 2016; 2:e1600188. [PMID: 27574702 PMCID: PMC5001810 DOI: 10.1126/sciadv.1600188] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 07/29/2016] [Indexed: 05/18/2023]
Abstract
Growth factors (GFs) are powerful signaling molecules with the potential to drive regenerative strategies, including bone repair and vascularization. However, GFs are typically delivered in soluble format at supraphysiological doses because of rapid clearance and limited therapeutic impact. These high doses have serious side effects and are expensive. Although it is well established that GF interactions with extracellular matrix proteins such as fibronectin control GF presentation and activity, a translation-ready approach to unlocking GF potential has not been realized. We demonstrate a simple, robust, and controlled material-based approach to enhance the activity of GFs during tissue healing. The underlying mechanism is based on spontaneous fibrillar organization of fibronectin driven by adsorption onto the polymer poly(ethyl acrylate). Fibrillar fibronectin on this polymer, but not a globular conformation obtained on control polymers, promotes synergistic presentation of integrin-binding sites and bound bone morphogenetic protein 2 (BMP-2), which enhances mesenchymal stem cell osteogenesis in vitro and drives full regeneration of a nonhealing bone defect in vivo at low GF concentrations. This simple and translatable technology could unlock the full regenerative potential of GF therapies while improving safety and cost-effectiveness.
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Affiliation(s)
- Virginia Llopis-Hernández
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, UK
| | - Marco Cantini
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, UK
| | - Cristina González-García
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, UK
| | - Zhe A. Cheng
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, UK
| | - Jingli Yang
- Center for Cell Engineering, Institute of Molecular Cell and Systems Biology, University of Glasgow, Joseph Black Building, University Avenue, Glasgow G12 8QQ, UK
| | - Penelope M Tsimbouri
- Center for Cell Engineering, Institute of Molecular Cell and Systems Biology, University of Glasgow, Joseph Black Building, University Avenue, Glasgow G12 8QQ, UK
| | - Andrés J. García
- Woodruff School of Mechanical Engineering, Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, 315 First Drive, Atlanta, GA 30332, USA
- Corresponding author. . (M.S.-S.); . (M.J.D.); . (A.J.G.)
| | - Matthew J. Dalby
- Center for Cell Engineering, Institute of Molecular Cell and Systems Biology, University of Glasgow, Joseph Black Building, University Avenue, Glasgow G12 8QQ, UK
- Corresponding author. . (M.S.-S.); . (M.J.D.); . (A.J.G.)
| | - Manuel Salmerón-Sánchez
- Division of Biomedical Engineering, School of Engineering, University of Glasgow, Glasgow G12 8LT, UK
- Corresponding author. . (M.S.-S.); . (M.J.D.); . (A.J.G.)
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Liang X, Garcia BL, Visai L, Prabhakaran S, Meenan NAG, Potts JR, Humphries MJ, Höök M. Allosteric Regulation of Fibronectin/α5β1 Interaction by Fibronectin-Binding MSCRAMMs. PLoS One 2016; 11:e0159118. [PMID: 27434228 PMCID: PMC4951027 DOI: 10.1371/journal.pone.0159118] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 06/27/2016] [Indexed: 12/03/2022] Open
Abstract
Adherence of microbes to host tissues is a hallmark of infectious disease and is often mediated by a class of adhesins termed MSCRAMMs (Microbial Surface Components Recognizing Adhesive Matrix Molecules). Numerous pathogens express MSCRAMMs that specifically bind the heterodimeric human glycoprotein fibronectin (Fn). In addition to roles in adhesion, Fn-binding MSCRAMMs exploit physiological Fn functions. For example, several pathogens can invade host cells by a mechanism whereby MSCRAMM-bound Fn bridges interaction with α5β1 integrin. Here, we investigate two Fn-binding MSCRAMMs, FnBPA (Staphylococcus aureus) and BBK32 (Borrelia burgdorferi) to probe structure-activity relationships of MSCRAMM-induced Fn/α5β1integrin activation. Circular dichroism, fluorescence resonance energy transfer, and dynamic light scattering techniques uncover a conformational rearrangement of Fn involving domains distant from the MSCRAMM binding site. Surface plasmon resonance experiments demonstrate a significant enhancement of Fn/α5β1 integrin affinity in the presence of FnBPA or BBK32. Detailed kinetic analysis of these interactions reveal that this change in affinity can be attributed solely to an increase in the initial Fn/α5β1 on-rate and that this rate-enhancement is dependent on high-affinity Fn-binding by MSCRAMMs. These data implicate MSCRAMM-induced perturbation of specific intramolecular contacts within the Fn heterodimer resulting in activation by exposing previously cryptic α5β1 interaction motifs. By correlating structural changes in Fn to a direct measurement of increased Fn/α5β1 affinity, this work significantly advances our understanding of the structural basis for the modulation of integrin function by Fn-binding MSCRAMMs.
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Affiliation(s)
- Xiaowen Liang
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX, 77030, United States of America
| | - Brandon L. Garcia
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX, 77030, United States of America
| | - Livia Visai
- Dep. of Molecular Medicine, UdR INSTM, Center for Tissue Engineering (C.I.T.), University of Pavia, 27100, Pavia, Italy
- Dep. of Occupational Medicine, Ergonomy and Disability, Salvatore Maugeri Foundation, IRCCS, Nanotechnology Laboratory, 27100, Pavia, Italy
| | - Sabitha Prabhakaran
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX, 77030, United States of America
| | | | - Jennifer R. Potts
- Department of Biology, University of York, York, YO10 5DD, United Kingdom
| | - Martin J. Humphries
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, United Kingdom
| | - Magnus Höök
- Center for Infectious and Inflammatory Diseases, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX, 77030, United States of America
- * E-mail:
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45
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Gudzenko T, Franz CM. Studying early stages of fibronectin fibrillogenesis in living cells by atomic force microscopy. Mol Biol Cell 2016; 26:3190-204. [PMID: 26371081 PMCID: PMC4569311 DOI: 10.1091/mbc.e15-06-0421] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Time-lapse atomic force microscopy imaging is used to visualize the initial stages of fibronectin fibrillogenesis directly in living cells with high resolution. This approach provides new structural and mechanistic details, such as a stepwise extension mechanism and an accelerating effect of extracellular Mn2+ on early FN fibrillogenesis. Fibronectin (FN) is an extracellular matrix protein that can be assembled by cells into large fibrillar networks, but the dynamics of FN remodeling and the transition through intermediate fibrillar stages are incompletely understood. Here we used a combination of fluorescence microscopy and time-lapse atomic force microscopy (AFM) to visualize initial stages of FN fibrillogenesis in living fibroblasts at high resolution. Initial FN nanofibrils form within <5 min of cell–matrix contact and subsequently extend at a rate of 0.25 μm/min at sites of cell membrane retraction. FN nanofibrils display a complex linear array of globular features spaced at varying distances, indicating the coexistence of different conformational states within the fibril. In some cases, initial fibrils extended in discrete increments of ∼800 nm during a series of cyclical membrane retractions, indicating a stepwise fibrillar extension mechanism. In presence of Mn2+, a known activator of integrin adhesion to FN, fibrillogenesis was accelerated almost threefold to 0.68 μm/min and fibrillar dimensions were increased, underlining the importance of integrin activation for early FN fibrillogenesis. FN fibrillogenesis visualized by time-lapse AFM thus provides new structural and mechanistic insight into initial steps of cell-driven FN fibrillogenesis.
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Affiliation(s)
- Tetyana Gudzenko
- DFG-Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Clemens M Franz
- DFG-Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany )
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Abstract
Fibronectin is a large vertebrate glycoprotein that is found in soluble and insoluble forms and involved in diverse processes. Protomeric fibronectin is a dimer of subunits, each of which comprises 29-31 modules - 12 type I, two type II and 15-17 type III. Plasma fibronectin is secreted by hepatocytes and circulates in a compact conformation before it binds to cell surfaces, converts to an extended conformation and is assembled into fibronectin fibrils. Here we review biophysical and structural studies that have shed light on how plasma fibronectin transitions from the compact to the extended conformation. The three types of modules each have a well-organized secondary and tertiary structure as defined by NMR and crystallography and have been likened to "beads on a string". There are flexible sequences in the N-terminal tail, between the fifth and sixth type I modules, between the first two and last two of the type III modules, and at the C-terminus. Several specific module-module interactions have been identified that likely maintain the compact quaternary structure of circulating fibronectin. The quaternary structure is perturbed in response to binding events, including binding of fibronectin to the surface of vertebrate cells for fibril assembly and to bacterial adhesins.
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Affiliation(s)
- Lisa M Maurer
- a Departments of Biomolecular Chemistry and Medicine , University of Wisconsin-Madison , Madison , WI , United States
| | - Wenjiang Ma
- a Departments of Biomolecular Chemistry and Medicine , University of Wisconsin-Madison , Madison , WI , United States
| | - Deane F Mosher
- a Departments of Biomolecular Chemistry and Medicine , University of Wisconsin-Madison , Madison , WI , United States
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47
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Siedlik MJ, Varner VD, Nelson CM. Pushing, pulling, and squeezing our way to understanding mechanotransduction. Methods 2016; 94:4-12. [PMID: 26318086 PMCID: PMC4761538 DOI: 10.1016/j.ymeth.2015.08.019] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 07/23/2015] [Accepted: 08/25/2015] [Indexed: 01/28/2023] Open
Abstract
Mechanotransduction is often described in the context of force-induced changes in molecular conformation, but molecular-scale mechanical stimuli arise in vivo in the context of complex, multicellular tissue structures. For this reason, we highlight and review experimental methods for investigating mechanotransduction across multiple length scales. We begin by discussing techniques that probe the response of individual molecules to applied force. We then move up in length scale to highlight techniques aimed at uncovering how cells transduce mechanical stimuli into biochemical activity. Finally, we discuss approaches for determining how these stimuli arise in multicellular structures. We expect that future work will combine techniques across these length scales to provide a more comprehensive understanding of mechanotransduction.
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Affiliation(s)
- Michael J Siedlik
- Department of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, United States
| | - Victor D Varner
- Department of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, United States
| | - Celeste M Nelson
- Department of Chemical & Biological Engineering, Princeton University, Princeton, NJ 08544, United States; Department of Molecular Biology, Princeton University, Princeton, NJ 08544, United States.
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48
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Kim HS, Yoon S, Son YJ, Park Y, Jung YM, Yoo HS. High-yield clicking and dissociation of doxorubicin nanoclusters exhibiting differential cellular uptakes and imaging. J Control Release 2015; 217:64-73. [DOI: 10.1016/j.jconrel.2015.08.037] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 07/14/2015] [Accepted: 08/19/2015] [Indexed: 12/26/2022]
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49
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Raoufi M, Das T, Schoen I, Vogel V, Brüggemann D, Spatz JP. Nanopore Diameters Tune Strain in Extruded Fibronectin Fibers. NANO LETTERS 2015; 15:6357-64. [PMID: 26360649 DOI: 10.1021/acs.nanolett.5b01356] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Fibronectin is present in the extracellular matrix and can be assembled into nanofibers in vivo by undergoing conformational changes. Here, we present a novel approach to prepare fibronectin nanofibers under physiological conditions using an extrusion approach through nanoporous aluminum oxide membranes. This one-step process can prepare nanofiber bundles up to a millimeter in length and with uniform fiber diameters in the nanometer range. Most importantly, by using different pore diameters and protein concentrations in the extrusion process, we could induce varying lasting structural changes in the fibers, which were monitored by Förster resonance energy transfer and should impose different physiological functions.
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Affiliation(s)
- Mohammad Raoufi
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems , Heisenbergstraße 3, D-70569 Stuttgart, Germany
- Department of Biophysical Chemistry, University of Heidelberg , INF 253, D-69120 Heidelberg, Germany
- Nanotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Science , Tehran 1417614411, Iran
| | - Tamal Das
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems , Heisenbergstraße 3, D-70569 Stuttgart, Germany
- Department of Biophysical Chemistry, University of Heidelberg , INF 253, D-69120 Heidelberg, Germany
| | - Ingmar Schoen
- Laboratory of Applied Mechanobiology, Department of Health Sciences and Technology ETH Zurich , Vladimir-Prelog Weg 4 (HCI F443), CH-8093 Zurich, Switzerland
| | - Viola Vogel
- Laboratory of Applied Mechanobiology, Department of Health Sciences and Technology ETH Zurich , Vladimir-Prelog Weg 4 (HCI F443), CH-8093 Zurich, Switzerland
| | - Dorothea Brüggemann
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems , Heisenbergstraße 3, D-70569 Stuttgart, Germany
- Department of Biophysical Chemistry, University of Heidelberg , INF 253, D-69120 Heidelberg, Germany
| | - Joachim P Spatz
- Department of New Materials and Biosystems, Max Planck Institute for Intelligent Systems , Heisenbergstraße 3, D-70569 Stuttgart, Germany
- Department of Biophysical Chemistry, University of Heidelberg , INF 253, D-69120 Heidelberg, Germany
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50
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Gudzenko T, Franz CM. Studying early stages of fibronectin fibrillogenesis in living cells by atomic force microscopy. Mol Biol Cell 2015. [DOI: 10.1091/mbc.e14-05-1026] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Fibronectin (FN) is an extracellular matrix protein that can be assembled by cells into large fibrillar networks, but the dynamics of FN remodeling and the transition through intermediate fibrillar stages are incompletely understood. Here we used a combination of fluorescence microscopy and time-lapse atomic force microscopy (AFM) to visualize initial stages of FN fibrillogenesis in living fibroblasts at high resolution. Initial FN nanofibrils form within <5 min of cell–matrix contact and subsequently extend at a rate of 0.25 μm/min at sites of cell membrane retraction. FN nanofibrils display a complex linear array of globular features spaced at varying distances, indicating the coexistence of different conformational states within the fibril. In some cases, initial fibrils extended in discrete increments of ∼800 nm during a series of cyclical membrane retractions, indicating a stepwise fibrillar extension mechanism. In presence of Mn2+, a known activator of integrin adhesion to FN, fibrillogenesis was accelerated almost threefold to 0.68 μm/min and fibrillar dimensions were increased, underlining the importance of integrin activation for early FN fibrillogenesis. FN fibrillogenesis visualized by time-lapse AFM thus provides new structural and mechanistic insight into initial steps of cell-driven FN fibrillogenesis.
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Affiliation(s)
- Tetyana Gudzenko
- DFG–Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Clemens M. Franz
- DFG–Center for Functional Nanostructures, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
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