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Chen H, Wang S, Cao Y, Lei H. Molecular Force Sensors for Biological Application. Int J Mol Sci 2024; 25:6198. [PMID: 38892386 PMCID: PMC11173168 DOI: 10.3390/ijms25116198] [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: 04/29/2024] [Revised: 05/29/2024] [Accepted: 05/29/2024] [Indexed: 06/21/2024] Open
Abstract
The mechanical forces exerted by cells on their surrounding microenvironment are known as cellular traction forces. These forces play crucial roles in various biological processes, such as tissue development, wound healing and cell functions. However, it is hard for traditional techniques to measure cellular traction forces accurately because their magnitude (from pN to nN) and the length scales over which they occur (from nm to μm) are extremely small. In order to fully understand mechanotransduction, highly sensitive tools for measuring cellular forces are needed. Current powerful techniques for measuring traction forces include traction force microscopy (TFM) and fluorescent molecular force sensors (FMFS). In this review, we elucidate the force imaging principles of TFM and FMFS. Then we highlight the application of FMFS in a variety of biological processes and offer our perspectives and insights into the potential applications of FMFS.
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Affiliation(s)
- Huiyan Chen
- National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, China; (H.C.); (S.W.)
| | - Shouhan Wang
- National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, China; (H.C.); (S.W.)
| | - Yi Cao
- National Laboratory of Solid State Microstructure, Department of Physics, Nanjing University, Nanjing 210093, China; (H.C.); (S.W.)
| | - Hai Lei
- School of Physics, Zhejiang University, Hangzhou 310027, China
- Institute for Advanced Study in Physics, Zhejiang University, Hangzhou 310027, China
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2
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Stock C. pH-regulated single cell migration. Pflugers Arch 2024; 476:639-658. [PMID: 38214759 PMCID: PMC11006768 DOI: 10.1007/s00424-024-02907-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Revised: 12/21/2023] [Accepted: 01/02/2024] [Indexed: 01/13/2024]
Abstract
Over the last two decades, extra- and intracellular pH have emerged as fundamental regulators of cell motility. Fundamental physiological and pathological processes relying on appropriate cell migration, such as embryonic development, wound healing, and a proper immune defense on the one hand, and autoimmune diseases, metastatic cancer, and the progression of certain parasitic diseases on the other, depend on surrounding pH. In addition, migrating single cells create their own localized pH nanodomains at their surface and in the cytosol. By this means, the migrating cells locally modulate their adhesion to, and the re-arrangement and digestion of, the extracellular matrix. At the same time, the cytosolic nanodomains tune cytoskeletal dynamics along the direction of movement resulting in concerted lamellipodia protrusion and rear end retraction. Extracellular pH gradients as found in wounds, inflamed tissues, or the periphery of tumors stimulate directed cell migration, and long-term exposure to acidic conditions can engender a more migratory and invasive phenotype persisting for hours up to several generations of cells after they have left the acidic milieu. In the present review, the different variants of pH-dependent single cell migration are described. The underlying pH-dependent molecular mechanisms such as conformational changes of adhesion molecules, matrix protease activity, actin (de-)polymerization, and signaling events are explained, and molecular pH sensors stimulated by H+ signaling are presented.
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Affiliation(s)
- Christian Stock
- Department of Gastroenterology, Hepatology, Infectiology & Endocrinology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
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3
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Osório LA, Silva E, Mackay RE. A Review of Biomaterials and Scaffold Fabrication for Organ-on-a-Chip (OOAC) Systems. Bioengineering (Basel) 2021; 8:113. [PMID: 34436116 PMCID: PMC8389238 DOI: 10.3390/bioengineering8080113] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/26/2021] [Accepted: 08/02/2021] [Indexed: 12/12/2022] Open
Abstract
Drug and chemical development along with safety tests rely on the use of numerous clinical models. This is a lengthy process where animal testing is used as a standard for pre-clinical trials. However, these models often fail to represent human physiopathology. This may lead to poor correlation with results from later human clinical trials. Organ-on-a-Chip (OOAC) systems are engineered microfluidic systems, which recapitulate the physiochemical environment of a specific organ by emulating the perfusion and shear stress cellular tissue undergoes in vivo and could replace current animal models. The success of culturing cells and cell-derived tissues within these systems is dependent on the scaffold chosen; hence, scaffolds are critical for the success of OOACs in research. A literature review was conducted looking at current OOAC systems to assess the advantages and disadvantages of different materials and manufacturing techniques used for scaffold production; and the alternatives that could be tailored from the macro tissue engineering research field.
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Affiliation(s)
- Luana A. Osório
- Department of Mechanical, Aerospace and Civil Engineering, Brunel University London, Uxbridge UB8 3PH, UK;
| | - Elisabete Silva
- Department of Life Science, Brunel University London, Uxbridge UB8 3PH, UK;
| | - Ruth E. Mackay
- Department of Mechanical, Aerospace and Civil Engineering, Brunel University London, Uxbridge UB8 3PH, UK;
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4
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Gagnon KB, Delpire E. Sodium Transporters in Human Health and Disease. Front Physiol 2021; 11:588664. [PMID: 33716756 PMCID: PMC7947867 DOI: 10.3389/fphys.2020.588664] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 10/06/2020] [Indexed: 12/12/2022] Open
Abstract
Sodium (Na+) electrochemical gradients established by Na+/K+ ATPase activity drives the transport of ions, minerals, and sugars in both excitable and non-excitable cells. Na+-dependent transporters can move these solutes in the same direction (cotransport) or in opposite directions (exchanger) across both the apical and basolateral plasma membranes of polarized epithelia. In addition to maintaining physiological homeostasis of these solutes, increases and decreases in sodium may also initiate, directly or indirectly, signaling cascades that regulate a variety of intracellular post-translational events. In this review, we will describe how the Na+/K+ ATPase maintains a Na+ gradient utilized by multiple sodium-dependent transport mechanisms to regulate glucose uptake, excitatory neurotransmitters, calcium signaling, acid-base balance, salt-wasting disorders, fluid volume, and magnesium transport. We will discuss how several Na+-dependent cotransporters and Na+-dependent exchangers have significant roles in human health and disease. Finally, we will discuss how each of these Na+-dependent transport mechanisms have either been shown or have the potential to use Na+ in a secondary role as a signaling molecule.
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Affiliation(s)
- Kenneth B. Gagnon
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, United States
| | - Eric Delpire
- Department of Anesthesiology, School of Medicine, Vanderbilt University, Nashville, TN, United States
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5
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Smith AM, Senior JJ. Alginate Hydrogels with Tuneable Properties. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2021; 178:37-61. [PMID: 33547500 DOI: 10.1007/10_2020_161] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Alginate is a material that has many biomedical applications due to its low toxicity and a variety of favourable physical properties. In particular, the ease in which hydrogels are formed from alginate and the variety of mechanical behaviours that can be imparted on the hydrogels, by understanding alginate chemistry and intuitive design, has made alginate the most widely investigated polysaccharide used for tissue engineering. This chapter provides an overview of alginate, from how the source and natural variations in composition can influence mechanical properties of alginate hydrogels, through to some innovative techniques used to modify and functionalise the hydrogels designed specifically for cell-based therapies. The main focus is on how these strategies of understanding and controlling the chemistry of alginates have resulted in the development of hydrogels that can be tuned to deliver the physical behaviours required for successful application. This will also highlight how research on the physicochemical properties has helped alginate evolve from a structural polysaccharide in brown seaweed into a highly tuneable, multifunctional, smart biomaterial, which is likely to find further biomedical applications in the future.
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Affiliation(s)
- Alan M Smith
- Department of Pharmacy, School of Applied Sciences, University of Huddersfield, Huddersfield, UK.
| | - Jessica J Senior
- Department of Pharmacy, School of Applied Sciences, University of Huddersfield, Huddersfield, UK
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6
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In vitro analysis of the trajectories of adhesive microbubbles approaching endothelial cells. J Colloid Interface Sci 2020; 578:758-767. [PMID: 32574909 DOI: 10.1016/j.jcis.2020.06.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 05/30/2020] [Accepted: 06/02/2020] [Indexed: 11/21/2022]
Abstract
Adhesion is a key process when ultrasound contrast agents, i.e. microbubbles, approach pathological tissues. A way to accomplish tumour targeting is to tether surface engineered microbubbles to endothelial cells of the up-regulated vascularization of cancer tissues. This can be achieved by coupling the microbubbles surface with the Arginine-Glycine-Aspartate, RGD, sequence. Such molecule interacts with the integrin receptors placed on the endothelial cells. Stability and trajectories of RGD modified lipid shelled MBs have been analysed in vitro using microchannels coated with human umbilical vein endothelial cells, HUVEC. In the microchannels realistic conditions, close to the physiological ones, were reproduced replicating shear rate, roughness comparable to the endothelium and channel size mimicking the postcapillary venules. In these conditions, the analysis of the trajectories close to the walls highlights a substantial difference between the modified MBs and the plain ones. Moreover, MBs adhesion has dynamic features recalling the motion of neutrophils engaged near the substrate such as rolling, translations and transient detachments. These findings are useful for the optimization of in vivo imaging and targeting functions.
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7
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Pethő Z, Najder K, Carvalho T, McMorrow R, Todesca LM, Rugi M, Bulk E, Chan A, Löwik CWGM, Reshkin SJ, Schwab A. pH-Channeling in Cancer: How pH-Dependence of Cation Channels Shapes Cancer Pathophysiology. Cancers (Basel) 2020; 12:E2484. [PMID: 32887220 PMCID: PMC7565548 DOI: 10.3390/cancers12092484] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 12/20/2022] Open
Abstract
Tissue acidosis plays a pivotal role in tumor progression: in particular, interstitial acidosis promotes tumor cell invasion, and is a major contributor to the dysregulation of tumor immunity and tumor stromal cells. The cell membrane and integral membrane proteins commonly act as important sensors and transducers of altered pH. Cell adhesion molecules and cation channels are prominent membrane proteins, the majority of which is regulated by protons. The pathophysiological consequences of proton-sensitive ion channel function in cancer, however, are scarcely considered in the literature. Thus, the main focus of this review is to highlight possible events in tumor progression and tumor immunity where the pH sensitivity of cation channels could be of great importance.
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Affiliation(s)
- Zoltán Pethő
- Institute of Physiology II, University Münster, 48147 Münster, Germany; (K.N.); (L.M.T.); (M.R.); (E.B.); (A.S.)
| | - Karolina Najder
- Institute of Physiology II, University Münster, 48147 Münster, Germany; (K.N.); (L.M.T.); (M.R.); (E.B.); (A.S.)
| | - Tiago Carvalho
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari, 90126 Bari, Italy; (T.C.); (S.J.R.)
| | - Roisin McMorrow
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, 3035 GD Rotterdam, The Netherlands; (R.M.); (C.W.G.M.L.)
| | - Luca Matteo Todesca
- Institute of Physiology II, University Münster, 48147 Münster, Germany; (K.N.); (L.M.T.); (M.R.); (E.B.); (A.S.)
| | - Micol Rugi
- Institute of Physiology II, University Münster, 48147 Münster, Germany; (K.N.); (L.M.T.); (M.R.); (E.B.); (A.S.)
| | - Etmar Bulk
- Institute of Physiology II, University Münster, 48147 Münster, Germany; (K.N.); (L.M.T.); (M.R.); (E.B.); (A.S.)
| | - Alan Chan
- Percuros B.V., 2333 CL Leiden, The Netherlands;
| | - Clemens W. G. M. Löwik
- Department of Radiology and Nuclear Medicine, Erasmus Medical Center, 3035 GD Rotterdam, The Netherlands; (R.M.); (C.W.G.M.L.)
- Department of Oncology CHUV, UNIL and Ludwig Cancer Center, 1011 Lausanne, Switzerland
| | - Stephan J. Reshkin
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari, 90126 Bari, Italy; (T.C.); (S.J.R.)
| | - Albrecht Schwab
- Institute of Physiology II, University Münster, 48147 Münster, Germany; (K.N.); (L.M.T.); (M.R.); (E.B.); (A.S.)
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8
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Kang SM, Lee JH, Huh YS, Takayama S. Alginate Microencapsulation for Three-Dimensional In Vitro Cell Culture. ACS Biomater Sci Eng 2020; 7:2864-2879. [PMID: 34275299 DOI: 10.1021/acsbiomaterials.0c00457] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Advances in microscale 3D cell culture systems have helped to elucidate cellular physiology, understand mechanisms of stem cell differentiation, produce pathophysiological models, and reveal important cell-cell and cell-matrix interactions. An important consideration for such studies is the choice of material for encapsulating cells and associated extracellular matrix (ECM). This Review focuses on the use of alginate hydrogels, which are versatile owing to their simple gelation process following an ionic cross-linking mechanism in situ, with no need for procedures that can be potentially toxic to cells, such as heating, the use of solvents, and UV exposure. This Review aims to give some perspectives, particularly to researchers who typically work more with poly(dimethylsiloxane) (PDMS), on the use of alginate as an alternative material to construct microphysiological cell culture systems. More specifically, this Review describes how physicochemical characteristics of alginate hydrogels can be tuned with regards to their biocompatibility, porosity, mechanical strength, ligand presentation, and biodegradability. A number of cell culture applications are also described, and these are subcategorized according to whether the alginate material is used to homogeneously embed cells, to micropattern multiple cellular microenvironments, or to provide an outer shell that creates a space in the core for cells and other ECM components. The Review ends with perspectives on future challenges and opportunities for 3D cell culture applications.
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Affiliation(s)
- Sung-Min Kang
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, 30332, United States of America.,The Parker H Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, 30332, United States of America.,NanoBio High-Tech Materials Research Center, Department of Biological Engineering, Inha University, 100 Inha-ro, Incheon, 22212, Republic of Korea
| | - Ji-Hoon Lee
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, 30332, United States of America.,The Parker H Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, 30332, United States of America
| | - Yun Suk Huh
- NanoBio High-Tech Materials Research Center, Department of Biological Engineering, Inha University, 100 Inha-ro, Incheon, 22212, Republic of Korea
| | - Shuichi Takayama
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory School of Medicine, Atlanta, 30332, United States of America.,The Parker H Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, 30332, United States of America
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9
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Iorio J, Duranti C, Lottini T, Lastraioli E, Bagni G, Becchetti A, Arcangeli A. K V11.1 Potassium Channel and the Na +/H + Antiporter NHE1 Modulate Adhesion-Dependent Intracellular pH in Colorectal Cancer Cells. Front Pharmacol 2020; 11:848. [PMID: 32587517 PMCID: PMC7297984 DOI: 10.3389/fphar.2020.00848] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 05/22/2020] [Indexed: 12/16/2022] Open
Abstract
Increasing evidence indicates that ion channels and transporters cooperate in regulating different aspects of tumor pathophysiology. In cancer cells, H+/HCO3- transporters usually invert the transmembrane pH gradient typically observed in non-neoplastic cells, which is thought to contribute to cancer malignancy. To what extent the pH-regulating transporters are functionally linked to K+ channels, which are central regulators of cell membrane potential (Vm), is unclear. We thus investigated in colorectal cancer cells the implication of the pH-regulating transporters and KV11.1 (also known as hERG1) in the pH modifications stimulated by integrin-dependent cell adhesion. Colorectal cancer cell lines (HCT 116 and HT 29) were seeded onto β1 integrin-dependent substrates, collagen I and fibronectin. This led to a transient cytoplasmic alkalinization, which peaked at 90 min of incubation, lasted approximately 180 min, and was inhibited by antibodies blocking the β1 integrin. The effect was sensitive to amiloride (10 µM) and cariporide (5 µM), suggesting that it was mainly caused by the activity of the Na+/H+ antiporter NHE1. Blocking KV11.1 with E4031 shows that channel activity contributed to modulate the β1 integrin-dependent pHi increase. Interestingly, both NHE1 and KV11.1 modulated the colorectal cancer cell motility triggered by β1 integrin-dependent adhesion. Finally, the β1 integrin subunit, KV11.1 and NHE1 co-immunoprecipitated in colorectal cancer cells seeded onto Collagen I, suggesting the formation of a macromolecular complex following integrin-mediated adhesion. We conclude that the interaction between KV11.1, NHE1, and β1 integrin contributes to regulate colorectal cancer intracellular pH in relation to the tumor microenvironment, suggesting novel pharmacological targets to counteract pro-invasive and, hence, pro-metastatic behavior in colorectal cancer.
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Affiliation(s)
- Jessica Iorio
- Section of Internal Medicine, Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Claudia Duranti
- Section of Internal Medicine, Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Tiziano Lottini
- Section of Internal Medicine, Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Elena Lastraioli
- Section of Internal Medicine, Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Giacomo Bagni
- Section of Internal Medicine, Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Andrea Becchetti
- Department of Biotechnology and Biosciences, University of Milano Bicocca, Milano, Italy
| | - Annarosa Arcangeli
- Section of Internal Medicine, Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
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10
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Harjumäki R, Zhang X, Nugroho RWN, Farooq M, Lou YR, Yliperttula M, Valle-Delgado JJ, Österberg M. AFM Force Spectroscopy Reveals the Role of Integrins and Their Activation in Cell–Biomaterial Interactions. ACS APPLIED BIO MATERIALS 2020; 3:1406-1417. [DOI: 10.1021/acsabm.9b01073] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Riina Harjumäki
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland
- Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, FI-00014 Helsinki, Finland
| | - Xue Zhang
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland
| | - Robertus Wahyu N. Nugroho
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland
| | - Muhammad Farooq
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland
| | - Yan-Ru Lou
- Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, FI-00014 Helsinki, Finland
| | - Marjo Yliperttula
- Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, FI-00014 Helsinki, Finland
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, I-35131 Padova, Italy
| | - Juan José Valle-Delgado
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland
| | - Monika Österberg
- Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University, FI-00076 Aalto, Finland
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11
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Single-Cell Acoustic Force Spectroscopy: Resolving Kinetics and Strength of T Cell Adhesion to Fibronectin. Cell Rep 2019; 24:3008-3016. [PMID: 30208324 DOI: 10.1016/j.celrep.2018.08.034] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 03/21/2018] [Accepted: 08/13/2018] [Indexed: 01/13/2023] Open
Abstract
Assessing the strength and kinetics of molecular interactions of cells with the extracellular matrix is fundamental to understand cell adhesion processes. Given the relevance of these processes, there is a strong need for physical methods to quantitatively assess the mechanism of cell adhesion at the single-cell level, allowing discrimination of cells with different behaviors. Here we introduce single-cell acoustic force spectroscopy (scAFS), an approach that makes use of acoustic waves to exert controlled forces, up to 1 nN, to hundreds of individual cells in parallel. We demonstrate the potential of scAFS by measuring adhesion forces and kinetics of CD4+ T lymphocytes (CD4) to fibronectin. We determined that CD4 adhesion is accelerated by interleukin-7, their main regulatory cytokine, whereas CD4 binding strength remains the same. Activation of these cells likely increases their chance to bind to the vessel wall in the blood flow to infiltrate inflamed tissues and locally coordinate the immune response.
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12
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Li Z, Liu T, Yang J, Lin J, Xin SX. Characterization of adhesion properties of the cardiomyocyte integrins and extracellular matrix proteins using atomic force microscopy. J Mol Recognit 2019; 33:e2823. [PMID: 31709699 DOI: 10.1002/jmr.2823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 10/08/2019] [Accepted: 10/19/2019] [Indexed: 11/10/2022]
Abstract
Integrins are transmembrane adhesion receptors that play important roles in the cardiovascular system by interacting with the extracellular matrix (ECM). However, direct quantitative measurements of the adhesion properties of the integrins on cardiomyocyte (CM) and their ECM ligands are lacking. In this study, we used atomic force microscopy (AFM) to quantify the adhesion force (peak force and mean force) and binding probability between CM integrins and three main heart tissue ECM proteins, ie, collagen (CN), fibronectin (FN), and laminin (LN). Functionalizing the AFM probes with ECM proteins, we found that the peak force (mean force) was 61.69 ± 5.5 pN (76.54 ± 4.0 pN), 39.26 ± 4.4 pN (59.84 ± 3.6 pN), and 108.31 ± 4.2 pN (129.63 ± 6.0 pN), respectively, for the bond of CN-integrin, FN-integrin, and LN-integrin. The binding specificity between CM integrins and ECM proteins was verified by using monoclonal antibodies, where α10 - and α11 -integrin bind to CN, α3 - and α5 -integrin bind to FN, and α3 - and α7 -integrin bind to LN. Furthermore, adhesion properties of CM integrins under physiologically high concentrations of extracellular Ca2+ and Mg2+ were tested. Additional Ca2+ reduced the adhesion mean force to 68.81 ± 4.0 pN, 49.84 ± 3.3 pN, and 119.21 ± 5.8 pN and binding probability to 0.31, 0.34, 0.40 for CN, FN, and LN, respectively, whereas Mg2+ caused very minor changes to adhesion properties of CM integrins. Thus, adhesion properties between adult murine CM integrins and its main ECM proteins were characterized, paving the way for an improved understanding of CM mechanobiology.
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Affiliation(s)
- Zecheng Li
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China
| | - Tianqi Liu
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China
| | - Junxian Yang
- Institute of Biomechanics, School of Biosciences and Bioengineering, South China University of Technology, Guangzhou, China
| | - Jiangguo Lin
- Institute of Biomechanics, School of Biosciences and Bioengineering, South China University of Technology, Guangzhou, China
| | - Sherman Xuegang Xin
- School of Biomedical Engineering, Southern Medical University, Guangzhou, China.,School of Medicine, South China University of Technology, Guangzhou, China
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13
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Sanyour HJ, Li N, Rickel AP, Childs JD, Kinser CN, Hong Z. Membrane cholesterol and substrate stiffness co-ordinate to induce the remodelling of the cytoskeleton and the alteration in the biomechanics of vascular smooth muscle cells. Cardiovasc Res 2019; 115:1369-1380. [PMID: 30395154 PMCID: PMC11268160 DOI: 10.1093/cvr/cvy276] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 06/07/2018] [Accepted: 11/01/2018] [Indexed: 04/10/2024] Open
Abstract
AIMS Cholesterol not only deposits in foam cells at the atherosclerotic plaque, but also plays an important role as a regulator of cell migration in atherogenesis. In addition, the progression of atherosclerosis leads to arterial wall stiffening, and thus altering the micromechanical environment of vascular smooth muscle cells (VSMCs) in vivo. Our studies aim to test the hypothesis that membrane cholesterol and substrate stiffness co-ordinate to regulate VSMCs biomechanics, and thus potentially regulate VSMCs migration and atherosclerotic plaque formation. METHODS AND RESULTS Methyl-β-cyclodextrin was used to manipulate membrane cholesterol content in VSMCs isolated from the descending thoracic aorta of male Sprague-Dawley rats and cultured on Type I collagen-coated polyacrylamide gel substrates with varying stiffness. Atomic force microscopy (AFM) was used to determine VSMCs stiffness and integrin-fibronectin (FN) adhesion. The alignment of submembranous actin filaments was visualized with AFM and confocal microscopy. The constriction force of rat aorta was measured ex vivo using a multi-wire myograph system. Our results demonstrated that cholesterol-depletion and substrate-softening induced a significant decrease in VSMCs stiffness and adhesion to FN, as well as cytoskeletal disorganization. In addition, the contractile force of rat aorta was reduced upon cholesterol-depletion. Cholesterol-enrichment resulted in an increase in stiffness, adhesion to FN, cytoskeletal organization of VSMCs compared with the cholesterol-depleted cells, and enhanced contractile force of rat aortas compared with the cholesterol-depleted vessel rings. CONCLUSION Cell membrane cholesterol and substrate stiffness synergistically affect VSMCs elastic modulus (E-modulus) by regulating the organization of the actin cytoskeleton. Except for the 3.5 kPa gel substrate, cholesterol-depletion decreased VSMCs-FN adhesion force, adhesion loading rate, cytoskeletal orientation, and E-modulus compared with the control VSMCs. Conversely, cholesterol-enrichment significantly increased cytoskeleton orientation, stiffness, and VSMCs-FN cell adhesion force compared with both control and cholesterol-depleted VSMCs on a soft substrate.
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MESH Headings
- Animals
- Aorta, Thoracic/metabolism
- Aorta, Thoracic/pathology
- Aorta, Thoracic/physiopathology
- Atherosclerosis/metabolism
- Atherosclerosis/pathology
- Atherosclerosis/physiopathology
- Biomechanical Phenomena
- Cell Adhesion
- Cell Membrane/metabolism
- Cell Membrane/pathology
- Cells, Cultured
- Cholesterol/metabolism
- Cytoskeleton/metabolism
- Cytoskeleton/pathology
- Elastic Modulus
- Male
- Mechanotransduction, Cellular
- Microscopy, Atomic Force
- Microscopy, Confocal
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/pathology
- Muscle, Smooth, Vascular/physiopathology
- Myocytes, Smooth Muscle/metabolism
- Myocytes, Smooth Muscle/pathology
- Rats, Sprague-Dawley
- Stress, Mechanical
- Vascular Stiffness
- Vasoconstriction
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Affiliation(s)
- Hanna J. Sanyour
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Na Li
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Alex P. Rickel
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Josh D. Childs
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Courtney N. Kinser
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
| | - Zhongkui Hong
- Department of Biomedical Engineering, University of South Dakota, 4800 N Career Ave, Suite 221, Sioux Falls, SD 57107, USA
- BioSNTR, Sioux Falls, SD, USA
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14
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Ungai-Salánki R, Peter B, Gerecsei T, Orgovan N, Horvath R, Szabó B. A practical review on the measurement tools for cellular adhesion force. Adv Colloid Interface Sci 2019; 269:309-333. [PMID: 31128462 DOI: 10.1016/j.cis.2019.05.005] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/05/2019] [Accepted: 05/06/2019] [Indexed: 01/03/2023]
Abstract
Cell-cell and cell-matrix adhesions are fundamental in all multicellular organisms. They play a key role in cellular growth, differentiation, pattern formation and migration. Cell-cell adhesion is substantial in the immune response, pathogen-host interactions, and tumor development. The success of tissue engineering and stem cell implantations strongly depends on the fine control of live cell adhesion on the surface of natural or biomimetic scaffolds. Therefore, the quantitative and precise measurement of the adhesion strength of living cells is critical, not only in basic research but in modern technologies, too. Several techniques have been developed or are under development to quantify cell adhesion. All of them have their pros and cons, which has to be carefully considered before the experiments and interpretation of the recorded data. Current review provides a guide to choose the appropriate technique to answer a specific biological question or to complete a biomedical test by measuring cell adhesion.
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15
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Severino P, da Silva CF, Andrade LN, de Lima Oliveira D, Campos J, Souto EB. Alginate Nanoparticles for Drug Delivery and Targeting. Curr Pharm Des 2019; 25:1312-1334. [PMID: 31465282 DOI: 10.2174/1381612825666190425163424] [Citation(s) in RCA: 98] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Accepted: 04/15/2019] [Indexed: 12/31/2022]
Abstract
Nanotechnology refers to the control, manipulation, study and manufacture of structures and devices at the nanometer size range. The small size, customized surface, improved solubility and multi-functionality of nanoparticles will continue to create new biomedical applications, as nanoparticles allow to dominate stability, solubility and bioavailability, as well controlled release of drugs. The type of a nanoparticle, and its related chemical, physical and morphological properties influence its interaction with living cells, as well as determine the route of clearance and possible toxic effects. This field requires cross-disciplinary research and gives opportunities to design and develop multifunctional devices, which allow the diagnosis and treatment of devastating diseases. Over the past few decades, biodegradable polymers have been studied for the fabrication of drug delivery systems. There was extensive development of biodegradable polymeric nanoparticles for drug delivery and tissue engineering, in view of their applications in controlling the release of drugs, stabilizing labile molecules from degradation and site-specific drug targeting. The primary aim is to reduce dosing frequency and prolong the therapeutic outcomes. For this purpose, inert excipients should be selected, being biopolymers, e.g. sodium alginate, commonly used in controlled drug delivery. Nanoparticles composed of alginate (known as anionic polysaccharide widely distributed in the cell walls of brown algae which, when in contact with water, forms a viscous gum) have emerged as one of the most extensively characterized biomaterials used for drug delivery and targeting a set of administration routes. Their advantages include not only the versatile physicochemical properties, which allow chemical modifications for site-specific targeting but also their biocompatibility and biodegradation profiles, as well as mucoadhesiveness. Furthermore, mechanical strength, gelation, and cell affinity can be modulated by combining alginate nanoparticles with other polymers, surface tailoring using specific targeting moieties and by chemical or physical cross-linking. However, for every physicochemical modification in the macromolecule/ nanoparticles, a new toxicological profile may be obtained. In this paper, the different aspects related to the use of alginate nanoparticles for drug delivery and targeting have been revised, as well as how their toxicological profile will determine the therapeutic outcome of the drug delivery system.
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Affiliation(s)
- Patricia Severino
- Universidade Tiradentes (Unit), Av. Murilo Dantas, 300, Farolandia, Aracaju-SE, CEP 49.032-490, Brazil
- Instituto de Tecnologia e Pesquisa, Laboratório de Nanotecnologia e Nanomedicina (LNMed) Av. Murilo Dantas, 300, Aracaju - SE, CEP 49.032-490, Brazil
| | - Classius F da Silva
- Universidade Federal de Sao Paulo, Instituto de Ciências Ambientais, Quimicas e Farmaceuticas, Departamento de Engenharia Quimica, Rua Sao Nicolau, 210, Diadema - SP, CEP 09.913-030, Brazil
| | - Luciana N Andrade
- Universidade Tiradentes (Unit), Av. Murilo Dantas, 300, Farolandia, Aracaju-SE, CEP 49.032-490, Brazil
- Instituto de Tecnologia e Pesquisa, Laboratório de Nanotecnologia e Nanomedicina (LNMed) Av. Murilo Dantas, 300, Aracaju - SE, CEP 49.032-490, Brazil
| | - Daniele de Lima Oliveira
- Universidade Tiradentes (Unit), Av. Murilo Dantas, 300, Farolandia, Aracaju-SE, CEP 49.032-490, Brazil
- Instituto de Tecnologia e Pesquisa, Laboratório de Nanotecnologia e Nanomedicina (LNMed) Av. Murilo Dantas, 300, Aracaju - SE, CEP 49.032-490, Brazil
| | - Joana Campos
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Polo das Ciencias da Saude, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
| | - Eliana B Souto
- Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Coimbra (FFUC), Polo das Ciencias da Saude, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal
- CEB - Centre of Biological Engineering, University of Minho, Campus de Gualtar 4710-057 Braga, Portugal
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16
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Huang H, Sun Z, Hill MA, Meininger GA. A Calcium Mediated Mechanism Coordinating Vascular Smooth Muscle Cell Adhesion During KCl Activation. Front Physiol 2018; 9:1810. [PMID: 30618822 PMCID: PMC6305448 DOI: 10.3389/fphys.2018.01810] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 12/04/2018] [Indexed: 12/21/2022] Open
Abstract
Efficient mechanotransduction in vascular smooth muscle cells (VSMCs) is intimately coupled to physical coupling of the cell to extracellular matrix proteins (ECM) by integrins. Integrin adhesion receptors are essential for normal vascular function and defective integrin signaling is associated with cardiovascular disease. However, less is known about the mechanism of integrin activation in VSMCs in relation to vasoregulation. Our laboratory previously demonstrated that the vasoconstrictor Angiotensin II increases VSMC stiffness in concert with enhanced adhesion to fibronectin (FN), indicating an important role for adhesion in contraction. However, the mechanism of this coordination remains to be clarified. In this study, intracellular Ca2+ ([Ca2+]i) was hypothesized to link integrin activation through inside-out signaling pathways leading to enhanced adhesion in response to AII. By using atomic force microscopy (AFM) with an anti-α5 antibody coated AFM probe, we confirmed that cell stiffness was increased by AII, while we observed no change in adhesion to an α5 integrin antibody. This indicated that increases in cell adhesion to FN induced by AII were occurring through an integrin activation process, as increased membrane integrin expression/receptor density would have been accompanied by increased adhesion to the anti-α5 antibody. Further studies were performed using either KCl or BAPTA-AM to modulate the level of [Ca2+]i. After KCl, VSMCs showed a rapid transient increase in cell stiffness as well as cell adhesion to FN, and these two events were synchronized with superimposed transient increases in the level of [Ca2+]i, which was measured using the Ca2+ indicator, fluo-4. These relationships were unaffected in VSMCs pretreated with the myosin light chain kinase inhibitor, ML-7. In contrast, unstimulated VSMCs incubated with an intracellular calcium chelator, BAPTA-AM, showed reduced cell adhesion to FN as well the expected decrease in [Ca2+]i. These data suggest that in VSMCs, integrin activation is linked to signaling events tied to levels of [Ca2+]i while being less dependent on events at the level of contractile protein activation. These findings provide additional evidence to support a role for adhesion in VSMC contraction and suggest that following cell contractile activation, that adhesion may be regulated in tandem with the contractile event.
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Affiliation(s)
- Huang Huang
- Dalton Cardiovascular Research Center, Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Zhe Sun
- Dalton Cardiovascular Research Center, Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Michael A Hill
- Dalton Cardiovascular Research Center, Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
| | - Gerald A Meininger
- Dalton Cardiovascular Research Center, Department of Medical Pharmacology and Physiology, University of Missouri, Columbia, MO, United States
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17
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Koçer G, Jonkheijm P. About Chemical Strategies to Fabricate Cell-Instructive Biointerfaces with Static and Dynamic Complexity. Adv Healthc Mater 2018; 7:e1701192. [PMID: 29717821 DOI: 10.1002/adhm.201701192] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2017] [Revised: 02/12/2018] [Indexed: 12/21/2022]
Abstract
Properly functioning cell-instructive biointerfaces are critical for healthy integration of biomedical devices in the body and serve as decisive tools for the advancement of our understanding of fundamental cell biological phenomena. Studies are reviewed that use covalent chemistries to fabricate cell-instructive biointerfaces. These types of biointerfaces typically result in a static presentation of predefined cell-instructive cues. Chemically defined, but dynamic cell-instructive biointerfaces introduce spatiotemporal control over cell-instructive cues and present another type of biointerface, which promises a more biomimetic way to guide cell behavior. Therefore, strategies that offer control over the lateral sorting of ligands, the availability and molecular structure of bioactive ligands, and strategies that offer the ability to induce physical, chemical and mechanical changes in situ are reviewed. Specific attention is paid to state-of-the-art studies on dynamic, cell-instructive 3D materials. Future work is expected to further deepen our understanding of molecular and cellular biological processes investigating cell-type specific responses and the translational steps toward targeted in vivo applications.
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Affiliation(s)
- Gülistan Koçer
- TechMed Centre and MESA Institute for Nanotechnology; University of Twente; 7500 AE Enschede The Netherlands
- Institute of Biomaterials and Biomedical Engineering; University of Toronto; Toronto M5S 3G9 Ontario Canada
| | - Pascal Jonkheijm
- TechMed Centre and MESA Institute for Nanotechnology; University of Twente; 7500 AE Enschede The Netherlands
- Institute of Biomaterials and Biomedical Engineering; University of Toronto; Toronto M5S 3G9 Ontario Canada
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18
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Viji Babu PK, Rianna C, Belge G, Mirastschijski U, Radmacher M. Mechanical and migratory properties of normal, scar, and Dupuytren's fibroblasts. J Mol Recognit 2018; 31:e2719. [PMID: 29701269 DOI: 10.1002/jmr.2719] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/11/2018] [Accepted: 03/14/2018] [Indexed: 11/08/2022]
Abstract
Mechanical properties of myofibroblasts play a key role in Dupuytren's disease. Here, we used atomic force microscopy to measure the viscoelastic properties of 3 different types of human primary fibroblasts derived from a same patient: normal and scar dermal fibroblasts and palmar fascial fibroblasts from Dupuytren's nodules. Different stiffness hydrogels (soft ~1 kPa and stiff ~ 50 kPa) were used as cell culture matrix to mimic the mechanical properties of the natural tissues, and atomic force microscopy step response force curves were used to discriminate between elastic and viscous properties of cells. Since transforming growth factor-β1 (TGF-β1) is known to induce expression of α-smooth muscle actin positive stress fibers in myofibroblasts, we investigated the behavior of these fibroblasts before and after applying TGF-β1. Finally, we performed an in vitro cell motility test, the wound healing or scratch assay, to evaluate the migratory properties of these fibroblasts. We found that (1) Dupuytren's fibroblasts are stiffer than normal and scar fibroblasts, the elastic modulus E ranging from 4.4, 2.1, to 1.8 kPa, for Dupuytren's, normal and scar fibroblasts, respectively; (2) TGF-β1 enhances the level of α-smooth muscle actin expression and thus cell stiffness in Dupuytren's fibroblasts (E, ~6.2 kPa); (3) matrix stiffness influences cell mechanical properties most prominently in Dupuytren's fibroblasts; and (4) Dupuytren's fibroblasts migrate slower than the other fibroblasts by a factor of 3. Taking together, our results showed that mechanical and migratory properties of fibroblasts might help to discriminate between different pathological conditions, helping to identify and recognize specific cell phenotypes.
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Affiliation(s)
| | - Carmela Rianna
- Institute of Biophysics, University of Bremen, Bremen, Germany
| | - Gazanfer Belge
- Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Ursula Mirastschijski
- Department of Plastic, Reconstructive, and Aesthetic Surgery, Klinikum Bremen-Mitte, and Wound Repair Unit, CBIB, University of Bremen, Bremen, Germany
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19
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Knoops B, Becker S, Poncin MA, Glibert J, Derclaye S, Clippe A, Alsteens D. Specific Interactions Measured by AFM on Living Cells between Peroxiredoxin-5 and TLR4: Relevance for Mechanisms of Innate Immunity. Cell Chem Biol 2018; 25:550-559.e3. [PMID: 29551349 DOI: 10.1016/j.chembiol.2018.02.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 01/08/2018] [Accepted: 02/07/2018] [Indexed: 12/14/2022]
Abstract
Inflammation is a pathophysiological response of innate immunity to infection or tissue damage. This response is among others triggered by factors released by damaged or dying cells, termed damage-associated molecular pattern (DAMP) molecules that act as danger signals. DAMPs interact with pattern recognition receptors (PRRs) to contribute to the induction of inflammation. However, how released peroxiredoxins (PRDXs) are able to activate PRRs, such as Toll-like receptors (TLRs), remains elusive. Here, we used force-distance curve-based atomic force microscopy to investigate the molecular mechanisms by which extracellular human PRDX5 can activate a proinflammatory response. Single-molecule experiments demonstrated that PRDX5 binds to purified TLR4 receptors, on macrophage-differentiated THP-1 cells, and on human TLR4-transfected CHO cells. These findings suggest that extracellular PRDX5 can specifically trigger a proinflammatory response. Moreover, our work also revealed that PRDX5 binding induces a cellular mechanoresponse. Collectively, this study provides insights into the role of extracellular PRDX5 in innate immunity.
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Affiliation(s)
- Bernard Knoops
- Université catholique de Louvain, Institut des Sciences de la Vie (ISV), 1348 Louvain-la-Neuve, Belgium.
| | - Sarah Becker
- Université catholique de Louvain, Institut des Sciences de la Vie (ISV), 1348 Louvain-la-Neuve, Belgium
| | - Mégane Anne Poncin
- Université catholique de Louvain, Institut des Sciences de la Vie (ISV), 1348 Louvain-la-Neuve, Belgium
| | - Julien Glibert
- Université catholique de Louvain, Institut des Sciences de la Vie (ISV), 1348 Louvain-la-Neuve, Belgium
| | - Sylvie Derclaye
- Université catholique de Louvain, Institut des Sciences de la Vie (ISV), 1348 Louvain-la-Neuve, Belgium
| | - André Clippe
- Université catholique de Louvain, Institut des Sciences de la Vie (ISV), 1348 Louvain-la-Neuve, Belgium
| | - David Alsteens
- Université catholique de Louvain, Institut des Sciences de la Vie (ISV), 1348 Louvain-la-Neuve, Belgium.
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20
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Luo Z, Zhang S, Pan J, Shi R, Liu H, Lyu Y, Han X, Li Y, Yang Y, Xu Z, Sui Y, Luo E, Zhang Y, Wei S. Time-responsive osteogenic niche of stem cells: A sequentially triggered, dual-peptide loaded, alginate hybrid system for promoting cell activity and osteo-differentiation. Biomaterials 2018; 163:25-42. [PMID: 29452946 DOI: 10.1016/j.biomaterials.2018.02.025] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Revised: 01/27/2018] [Accepted: 02/09/2018] [Indexed: 01/24/2023]
Abstract
The efficacy of stem cell-based bone tissue engineering has been hampered by cell death and limited fate control. A smart cell culture system with the capability of sequentially delivering multiple factors in specific growth stages, like the mechanism of the natural extracellular matrix modulating tissue formation, is attractive for enhancing cell activity and controlling cell fate. Here, a bone forming peptide-1 (BFP-1)-laden mesoporous silica nanoparticles (pep@MSNs) incorporated adhesion peptide, containing the arginine-glycine-aspartic acid (RGD) domain, modified alginate hydrogel (RA) system (pep@MSNs-RA) was developed to promote the activity and stimulate osteo-differentiation of human mesenchymal stem cells (hMSCs) in sequence. The survivability and proliferation of hMSCs were enhanced in the adhesion peptide modified hydrogel. Next, BFP-1 released from pep@MSNs induced hMSCs osteo-differentiation after the proliferation stage. Moreover, BFP-1 near the cells was self-captured by the additional cell-peptide cross-linked networks formed by the ligands (RGD) binding to receptors on the cell surface, leading to long-term sustained osteo-stimulation of hMSCs. The results suggest that independent and sequential stimulation in proliferation and osteo-differentiation stages could synergistically enhance the survivability, expansion, and osteogenesis of hMSCs, as compared to stimulating alone or simultaneously. Overall, this study provided a new and valid strategy for stem cell expansion and osteo-differentiation in 2D or 3D culture systems, possessing potential applications in 3D bio-printing and tissue regeneration.
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Affiliation(s)
- Zuyuan Luo
- Central Laboratory, School and Hospital of Stomatology, Peking University, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing 100081, China; Laboratory for Biomaterials and Regenerative Medicine, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Siqi Zhang
- Laboratory for Biomaterials and Regenerative Medicine, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Jijia Pan
- Laboratory for Biomaterials and Regenerative Medicine, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Rui Shi
- Central Laboratory, School and Hospital of Stomatology, Peking University, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing 100081, China
| | - Hao Liu
- Central Laboratory, School and Hospital of Stomatology, Peking University, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing 100081, China
| | - Yalin Lyu
- Department of Stomatology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China.
| | - Xiao Han
- Department of Stomatology, Beijing Anzhen Hospital, Capital Medical University, Beijing 100029, China
| | - Yan Li
- Central Laboratory, School and Hospital of Stomatology, Peking University, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing 100081, China
| | - Yue Yang
- Department of Stomatology, Xuanwu Hospital, Capital Medical University, Beijing 100053, China
| | - Zhixiu Xu
- Department of Oral Pathology, School and Hospital of Stomatology, Peking University, Beijing 100081, China
| | - Yi Sui
- Central Laboratory, School and Hospital of Stomatology, Peking University, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing 100081, China
| | - En Luo
- Department of Oral and Maxillofacial Surgery, West China School and Hospital of Stomatology, Sichuan University, Chengdu 610041, China
| | - Yuanyuan Zhang
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA.
| | - Shicheng Wei
- Central Laboratory, School and Hospital of Stomatology, Peking University, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing 100081, China; Laboratory for Biomaterials and Regenerative Medicine, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.
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21
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Zemła J, Danilkiewicz J, Orzechowska B, Pabijan J, Seweryn S, Lekka M. Atomic force microscopy as a tool for assessing the cellular elasticity and adhesiveness to identify cancer cells and tissues. Semin Cell Dev Biol 2018; 73:115-124. [DOI: 10.1016/j.semcdb.2017.06.029] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 06/27/2017] [Accepted: 06/29/2017] [Indexed: 11/27/2022]
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22
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Burgos-Bravo F, Figueroa NL, Casanova-Morales N, Quest AFG, Wilson CAM, Leyton L. Single-molecule measurements of the effect of force on Thy-1/αvβ3-integrin interaction using nonpurified proteins. Mol Biol Cell 2017; 29:326-338. [PMID: 29212879 PMCID: PMC5996956 DOI: 10.1091/mbc.e17-03-0133] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Revised: 10/10/2017] [Accepted: 12/01/2017] [Indexed: 12/11/2022] Open
Abstract
Single-molecule measurements combined with a novel mathematical strategy were applied to accurately characterize how bimolecular interactions respond to mechanical force, especially when protein purification is not possible. Specifically, we studied the effect of force on Thy-1/αvβ3 integrin interaction, a mediator of neuron-astrocyte communication. Thy-1 and αvβ3 integrin mediate bidirectional cell-to-cell communication between neurons and astrocytes. Thy-1/αvβ3 interactions stimulate astrocyte migration and the retraction of neuronal prolongations, both processes in which internal forces are generated affecting the bimolecular interactions that maintain cell–cell adhesion. Nonetheless, how the Thy-1/αvβ3 interactions respond to mechanical cues is an unresolved issue. In this study, optical tweezers were used as a single-molecule force transducer, and the Dudko-Hummer-Szabo model was applied to calculate the kinetic parameters of Thy-1/αvβ3 dissociation. A novel experimental strategy was implemented to analyze the interaction of Thy-1-Fc with nonpurified αvβ3-Fc integrin, whereby nonspecific rupture events were corrected by using a new mathematical approach. This methodology permitted accurately estimating specific rupture forces for Thy-1-Fc/αvβ3-Fc dissociation and calculating the kinetic and transition state parameters. Force exponentially accelerated Thy-1/αvβ3 dissociation, indicating slip bond behavior. Importantly, nonspecific interactions were detected even for purified proteins, highlighting the importance of correcting for such interactions. In conclusion, we describe a new strategy to characterize the response of bimolecular interactions to forces even in the presence of nonspecific binding events. By defining how force regulates Thy-1/αvβ3 integrin binding, we provide an initial step towards understanding how the neuron–astrocyte pair senses and responds to mechanical cues.
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Affiliation(s)
- Francesca Burgos-Bravo
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies of Exercise, Metabolism and Cancer, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile
| | - Nataniel L Figueroa
- Physics Department, Pontificia Universidad Católica de Chile, 782-0436 Santiago, Chile
| | - Nathalie Casanova-Morales
- Biochemistry and Molecular Biology Department, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 838-0494 Santiago, Chile
| | - Andrew F G Quest
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile.,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies of Exercise, Metabolism and Cancer, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile
| | - Christian A M Wilson
- Biochemistry and Molecular Biology Department, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, 838-0494 Santiago, Chile
| | - Lisette Leyton
- Cellular Communication Laboratory, Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile .,Advanced Center for Chronic Diseases (ACCDiS), Center for Studies of Exercise, Metabolism and Cancer, Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, 838-0453 Santiago, Chile
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23
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Wu X, Muthuchamy M, Reddy DS. Atomic force microscopy investigations of fibronectin and α5β1-integrin signaling in neuroplasticity and seizure susceptibility in experimental epilepsy. Epilepsy Res 2017; 138:71-80. [DOI: 10.1016/j.eplepsyres.2017.10.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/15/2017] [Accepted: 10/19/2017] [Indexed: 12/15/2022]
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24
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Removal of ligand-bound liposomes from cell surfaces by microbubbles exposed to ultrasound. J Biol Phys 2017; 43:493-510. [PMID: 29124623 DOI: 10.1007/s10867-017-9465-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Accepted: 08/16/2017] [Indexed: 10/18/2022] Open
Abstract
Gas-filled microbubbles attached to cell surfaces can interact with focused ultrasound to create microstreaming of nearby fluid. We directly observed the ultrasound/microbubble interaction and documented that under certain conditions fluorescent particles that were attached to the surface of live cells could be removed. Fluorescently labeled liposomes that were larger than 500 nm in diameter were attached to the surface of endothelial cells using cRGD targeting to αvβ3 integrin. Microbubbles were attached to the surface of the cells through electrostatic interactions. Images taken before and after the ultrasound exposure were compared to document the effects on the liposomes. When exposed to ultrasound with peak negative pressure of 0.8 MPa, single microbubbles and groups of isolated microbubbles were observed to remove targeted liposomes from the cell surface. Liposomes were removed from a region on the cell surface that averaged 33.1 μm in diameter. The maximum distance between a single microbubble and a detached liposome was 34.5 μm. Single microbubbles were shown to be able to remove liposomes from over half the surface of a cell. The distance over which liposomes were removed was significantly dependent on the resting diameter of the microbubble. Clusters of adjoining microbubbles were not seen to remove liposomes. These observations demonstrate that the fluid shear forces generated by the ultrasound/microbubble interaction can remove liposomes from the surfaces of cells over distances that are greater than the diameter of the microbubble.
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25
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Sumarokova M, Iturri J, Toca-Herrera JL. Adhesion, unfolding forces, and molecular elasticity of fibronectin coatings: An atomic force microscopy study. Microsc Res Tech 2017; 81:38-45. [DOI: 10.1002/jemt.22954] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 08/24/2017] [Accepted: 09/26/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Maria Sumarokova
- Institute for Biophysics, Department of Nanobiotechnology; University of Natural Resources and Life Sciences Vienna (BOKU); Vienna 1190 Austria
| | - Jagoba Iturri
- Institute for Biophysics, Department of Nanobiotechnology; University of Natural Resources and Life Sciences Vienna (BOKU); Vienna 1190 Austria
| | - José L. Toca-Herrera
- Institute for Biophysics, Department of Nanobiotechnology; University of Natural Resources and Life Sciences Vienna (BOKU); Vienna 1190 Austria
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Angely C, Nguyen NM, Andre Dias S, Planus E, Pelle G, Louis B, Filoche M, Chenal A, Ladant D, Isabey D. Exposure to Bordetella pertussis adenylate cyclase toxin affects integrin-mediated adhesion and mechanics in alveolar epithelial cells. Biol Cell 2017; 109:293-311. [PMID: 28597954 DOI: 10.1111/boc.201600082] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 06/01/2017] [Accepted: 06/02/2017] [Indexed: 12/13/2022]
Abstract
BACKGROUND INFORMATION The adenylate cyclase (CyaA) toxin is a major virulent factor of Bordetella pertussis, the causative agent of whooping cough. CyaA toxin is able to invade eukaryotic cells where it produces high levels of cyclic adenosine monophosphate (cAMP) affecting cellular physiology. Whether CyaA toxin can modulate cell matrix adhesion and mechanics of infected cells remains largely unknown. RESULTS In this study, we use a recently proposed multiple bond force spectroscopy (MFS) with an atomic force microscope to assess the early phase of cell adhesion (maximal detachment and local rupture forces) and cell rigidity (Young's modulus) in alveolar epithelial cells (A549) for toxin exposure <1 h. At 30 min of exposure, CyaA toxin has a minimal effect on cell viability (>95%) at CyaA concentration of 0.5 nM, but a significant effect (≈81%) at 10 nM. MFS performed on A549 for three different concentrations (0.5, 5 and 10 nM) demonstrates that CyaA toxin significantly affects both cell adhesion (detachment forces are decreased) and cell mechanics (Young's modulus is increased). CyaA toxin (at 0.5 nM) assessed at three indentation/retraction speeds (2, 5 and 10 μm/s) significantly affects global detachment forces, local rupture events and Young modulus compared with control conditions, while an enzymatically inactive variant CyaAE5 has no effect. These results reveal the loading rate dependence of the multiple bonds newly formed between the cell and integrin-specific coated probe as well as the individual bond kinetics which are only slightly affected by the patho-physiological dose of CyaA toxin. Finally, theory of multiple bond force rupture enables us to deduce the bond number N which is reduced by a factor of 2 upon CyaA exposure (N ≈ 6 versus N ≈ 12 in control conditions). CONCLUSIONS MFS measurements demonstrate that adhesion and mechanical properties of A549 are deeply affected by exposure to the CyaA toxin but not to an enzymatically inactive variant. This indicates that the alteration of cell mechanics triggered by CyaA is a consequence of the increase in intracellular cAMP in these target cells. SIGNIFICANCE These results suggest that mechanical and adhesion properties of the cells appear as pertinent markers of cytotoxicity of CyaA toxin.
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Affiliation(s)
- Christelle Angely
- Inserm, U955, Equipe 13, Biomécanique & Appareil Respiratoire: une approche multi-échelle, Créteil Cedex, 94010, France.,Université Paris Est, UMRS 955, UPEC, Créteil Cedex, 94010, France.,CNRS, ERL 7240, Créteil Cedex, 94010, France
| | - Ngoc-Minh Nguyen
- Inserm, U955, Equipe 13, Biomécanique & Appareil Respiratoire: une approche multi-échelle, Créteil Cedex, 94010, France.,Université Paris Est, UMRS 955, UPEC, Créteil Cedex, 94010, France.,CNRS, ERL 7240, Créteil Cedex, 94010, France
| | - Sofia Andre Dias
- Inserm, U955, Equipe 13, Biomécanique & Appareil Respiratoire: une approche multi-échelle, Créteil Cedex, 94010, France.,Université Paris Est, UMRS 955, UPEC, Créteil Cedex, 94010, France.,CNRS, ERL 7240, Créteil Cedex, 94010, France
| | - Emmanuelle Planus
- Institute for Advanced Biosciences (IAB), Centre de Recherche UGA/Inserm U1209/CNRS UMR 5309, La Tronche 38700, France
| | - Gabriel Pelle
- Inserm, U955, Equipe 13, Biomécanique & Appareil Respiratoire: une approche multi-échelle, Créteil Cedex, 94010, France.,Université Paris Est, UMRS 955, UPEC, Créteil Cedex, 94010, France.,CNRS, ERL 7240, Créteil Cedex, 94010, France.,AP-HP, Groupe Hospitalier H. Mondor - A. Chenevier, Service des Explorations Fonctionnelles, Créteil Cedex, 94010, France
| | - Bruno Louis
- Inserm, U955, Equipe 13, Biomécanique & Appareil Respiratoire: une approche multi-échelle, Créteil Cedex, 94010, France.,Université Paris Est, UMRS 955, UPEC, Créteil Cedex, 94010, France.,CNRS, ERL 7240, Créteil Cedex, 94010, France
| | - Marcel Filoche
- Inserm, U955, Equipe 13, Biomécanique & Appareil Respiratoire: une approche multi-échelle, Créteil Cedex, 94010, France.,Université Paris Est, UMRS 955, UPEC, Créteil Cedex, 94010, France.,CNRS, ERL 7240, Créteil Cedex, 94010, France.,Laboratoire de Physique de la Matière Condensée, Ecole Polytechnique, CNRS, Université Paris Saclay, Palaiseau, 91128, France
| | - Alexandre Chenal
- Unité de Biochimie des Interactions Macromoléculaires (CNRS UMR 3528), Département de Biologie Structurale et Chimie, Institut Pasteur, Paris, 75014, France
| | - Daniel Ladant
- Unité de Biochimie des Interactions Macromoléculaires (CNRS UMR 3528), Département de Biologie Structurale et Chimie, Institut Pasteur, Paris, 75014, France
| | - Daniel Isabey
- Inserm, U955, Equipe 13, Biomécanique & Appareil Respiratoire: une approche multi-échelle, Créteil Cedex, 94010, France.,Université Paris Est, UMRS 955, UPEC, Créteil Cedex, 94010, France.,CNRS, ERL 7240, Créteil Cedex, 94010, France
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27
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Nguyen NM, Angely C, Andre Dias S, Planus E, Filoche M, Pelle G, Louis B, Isabey D. Characterisation of cellular adhesion reinforcement by multiple bond force spectroscopy in alveolar epithelial cells. Biol Cell 2017; 109:255-272. [DOI: 10.1111/boc.201600080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 05/09/2017] [Accepted: 05/11/2017] [Indexed: 11/27/2022]
Affiliation(s)
- Ngoc-Minh Nguyen
- Inserm; U955; Equipe 13; Biomécanique & Appareil Respiratoire; Créteil Cedex F-94010 France
- Université Paris Est; UMR S955, UPEC Créteil Cedex F-94010 France
- CNRS; ERL 7240 Créteil Cedex F-94010 France
| | - Christelle Angely
- Inserm; U955; Equipe 13; Biomécanique & Appareil Respiratoire; Créteil Cedex F-94010 France
- Université Paris Est; UMR S955, UPEC Créteil Cedex F-94010 France
- CNRS; ERL 7240 Créteil Cedex F-94010 France
| | - Sofia Andre Dias
- Inserm; U955; Equipe 13; Biomécanique & Appareil Respiratoire; Créteil Cedex F-94010 France
- Université Paris Est; UMR S955, UPEC Créteil Cedex F-94010 France
- CNRS; ERL 7240 Créteil Cedex F-94010 France
| | - Emmanuelle Planus
- Institute for Advanced Biosciences (IAB); Centre de Recherche UGA/Inserm U1209/CNRS UMR 5309; La Tronche 38700 France
| | - Marcel Filoche
- Inserm; U955; Equipe 13; Biomécanique & Appareil Respiratoire; Créteil Cedex F-94010 France
- Université Paris Est; UMR S955, UPEC Créteil Cedex F-94010 France
- CNRS; ERL 7240 Créteil Cedex F-94010 France
- Laboratoire de Physique de la Matière Condensée; Ecole Polytechnique; CNRS; Université Paris Saclay; Palaiseau 91128 France
| | - Gabriel Pelle
- Inserm; U955; Equipe 13; Biomécanique & Appareil Respiratoire; Créteil Cedex F-94010 France
- Université Paris Est; UMR S955, UPEC Créteil Cedex F-94010 France
- CNRS; ERL 7240 Créteil Cedex F-94010 France
- AP-HP; Groupe Hospitalier H. Mondor - A. Chenevier; Service des Explorations Fonctionnelles; Créteil Cedex F-94010 France
| | - Bruno Louis
- Inserm; U955; Equipe 13; Biomécanique & Appareil Respiratoire; Créteil Cedex F-94010 France
- Université Paris Est; UMR S955, UPEC Créteil Cedex F-94010 France
- CNRS; ERL 7240 Créteil Cedex F-94010 France
| | - Daniel Isabey
- Inserm; U955; Equipe 13; Biomécanique & Appareil Respiratoire; Créteil Cedex F-94010 France
- Université Paris Est; UMR S955, UPEC Créteil Cedex F-94010 France
- CNRS; ERL 7240 Créteil Cedex F-94010 France
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Drug-Loadable Calcium Alginate Hydrogel System for Use in Oral Bone Tissue Repair. Int J Mol Sci 2017; 18:ijms18050989. [PMID: 28481253 PMCID: PMC5454902 DOI: 10.3390/ijms18050989] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2017] [Revised: 05/01/2017] [Accepted: 05/02/2017] [Indexed: 01/23/2023] Open
Abstract
This study developed a drug-loadable hydrogel system with high plasticity and favorable biological properties to enhance oral bone tissue regeneration. Hydrogels of different calcium alginate concentrations were prepared. Their swelling ratio, degradation time, and bovine serum albumin (BSA) release rate were measured. Human periodontal ligament cells (hPDLCs) and bone marrow stromal cells (BMSCs) were cultured with both calcium alginate hydrogels and polylactic acid (PLA), and then we examined the proliferation of cells. Inflammatory-related factor gene expressions of hPDLCs and osteogenesis-related gene expressions of BMSCs were observed. Materials were implanted into the subcutaneous tissue of rabbits to determine the biosecurity properties of the materials. The materials were also implanted in mandibular bone defects and then scanned using micro-CT. The calcium alginate hydrogels caused less inflammation than the PLA. The number of mineralized nodules and the expression of osteoblast-related genes were significantly higher in the hydrogel group compared with the control group. When the materials were implanted in subcutaneous tissue, materials showed favorable biocompatibility. The calcium alginate hydrogels had superior osteoinductive bone ability to the PLA. The drug-loadable calcium alginate hydrogel system is a potential bone defect reparation material for clinical dental application.
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29
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Sankaran S, Jaatinen L, Brinkmann J, Zambelli T, Vörös J, Jonkheijm P. Cell Adhesion on Dynamic Supramolecular Surfaces Probed by Fluid Force Microscopy-Based Single-Cell Force Spectroscopy. ACS NANO 2017; 11:3867-3874. [PMID: 28319669 PMCID: PMC5406783 DOI: 10.1021/acsnano.7b00161] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Accepted: 03/20/2017] [Indexed: 05/23/2023]
Abstract
Biomimetic and stimuli-responsive cell-material interfaces are actively being developed to study and control various cell-dynamics phenomena. Since cells naturally reside in the highly dynamic and complex environment of the extracellular matrix, attempts are being made to replicate these conditions in synthetic biomaterials. Supramolecular chemistry, dealing with noncovalent interactions, has recently provided possibilities to incorporate such dynamicity and responsiveness in various types of architectures. Using a cucurbit[8]uril-based host-guest system, we have successfully established a dynamic and electrochemically responsive interface for the display of the integrin-specific ligand, Arg-Gly-Asp (RGD), to promote cell adhesion. Due to the weak nature of the noncovalent forces by which the components at the interface are held together, we expected that cell adhesion would also be weaker in comparison to traditional interfaces where ligands are usually immobilized by covalent linkages. To assess the stability and limitations of our noncovalent interfaces, we performed single-cell force spectroscopy studies using fluid force microscopy. This technique enabled us to measure rupture forces of multiple cells that were allowed to adhere for several hours on individual substrates. We found that the rupture forces of cells adhered to both the noncovalent and covalent interfaces were nearly identical for up to several hours. We have analyzed and elucidated the reasons behind this result as a combination of factors including the weak rupture force between linear Arg-Gly-Asp and integrin, high surface density of the ligand, and increase in effective concentration of the supramolecular components under spread cells. These characteristics enable the construction of highly dynamic biointerfaces without compromising cell-adhesive properties.
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Affiliation(s)
- Shrikrishnan Sankaran
- Bioinspired
Molecular Engineering Laboratory, MIRA Institute for
Biomedical Research and Technical Medicine and Molecular Nanofabrication Group,
MESA+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Leena Jaatinen
- Department
of Electronics and Communications Engineering, Tampere University of Technology, BioMediTech, Finn-Medi 1 L 4, Biokatu 6, FI-33520 Tampere, Finland
- Laboratory
of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, CH-8092 Zurich, Switzerland
| | - Jenny Brinkmann
- Bioinspired
Molecular Engineering Laboratory, MIRA Institute for
Biomedical Research and Technical Medicine and Molecular Nanofabrication Group,
MESA+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
| | - Tomaso Zambelli
- Laboratory
of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, CH-8092 Zurich, Switzerland
| | - Janos Vörös
- Laboratory
of Biosensors and Bioelectronics, Institute for Biomedical Engineering, ETH Zurich, CH-8092 Zurich, Switzerland
| | - Pascal Jonkheijm
- Bioinspired
Molecular Engineering Laboratory, MIRA Institute for
Biomedical Research and Technical Medicine and Molecular Nanofabrication Group,
MESA+ Institute for Nanotechnology, University
of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands
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30
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Cao H, Zhang W, Meng F, Guo J, Wang D, Qian S, Jiang X, Liu X, Chu PK. Osteogenesis Catalyzed by Titanium-Supported Silver Nanoparticles. ACS APPLIED MATERIALS & INTERFACES 2017; 9:5149-5157. [PMID: 28111942 DOI: 10.1021/acsami.6b15448] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Silver nanoparticles (Ag NPs) were widely explored for antimicrobial applications, whereas the translation into drugs and implantable antibacterial devices provoked serious concerns about their potential cytotoxicity. Herein, Ag NPs with diameters ranging from 4 to 19 nm were in situ fabricated and immobilized on titanium by using a plasma immersion ion implantation process. The particles have a population-dependent capability in activating the integrin α5 orchestrated MAPK/ERK signal cascade of osteoblast differentiation in rat bone marrow stem cells (BMSCs), and promoting osteointegration of titanium. It was demonstrated that the titanium-supported Ag NPs played an important role in motivating integrin α5 through triggering the galvanic hydrogen evolution reactions, which was found in positive correlation with the distribution density of the immobilized Ag NPs. Since cellular uptake is a key factor determining the cytotoxic performance of Ag NPs, the extracellular effects of immobilized Ag NPs on promoting osteogenesis provided new insights into the safe application of nanomaterials, and into designing and developing renewed antibacterial devices with selective toxicity.
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Affiliation(s)
- Huiliang Cao
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, China
| | - Wenjie Zhang
- Department of Prosthodontics, School of Medicine, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University , 639 Zhizaoju Road, Shanghai 200011, China
| | - Fanhao Meng
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, China
| | - Jinshu Guo
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, China
| | - Donghui Wang
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, China
| | - Shi Qian
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, China
| | - Xinquan Jiang
- Department of Prosthodontics, School of Medicine, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University , 639 Zhizaoju Road, Shanghai 200011, China
| | - Xuanyong Liu
- State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences , Shanghai 200050, China
| | - Paul K Chu
- Department of Physics and Materials Science, City University of Hong Kong , Tat Chee Avenue, Kowloon, Hong Kong, China
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31
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Stock C, Pedersen SF. Roles of pH and the Na +/H + exchanger NHE1 in cancer: From cell biology and animal models to an emerging translational perspective? Semin Cancer Biol 2016; 43:5-16. [PMID: 28007556 DOI: 10.1016/j.semcancer.2016.12.001] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 12/10/2016] [Indexed: 01/30/2023]
Abstract
Acidosis is characteristic of the solid tumor microenvironment. Tumor cells, because they are highly proliferative and anabolic, have greatly elevated metabolic acid production. To sustain a normal cytosolic pH homeostasis they therefore need to either extrude excess protons or to neutralize them by importing HCO3-, in both cases causing extracellular acidification in the poorly perfused tissue microenvironment. The Na+/H+ exchanger isoform 1 (NHE1) is a ubiquitously expressed acid-extruding membrane transport protein, and upregulation of its expression and/or activity is commonly correlated with tumor malignancy. The present review discusses current evidence on how altered pH homeostasis, and in particular NHE1, contributes to tumor cell motility, invasion, proliferation, and growth and facilitates evasion of chemotherapeutic cell death. We summarize data from in vitro studies, 2D-, 3D- and organotypic cell culture, animal models and human tissue, which collectively point to pH-regulation in general, and NHE1 in particular, as potential targets in combination chemotherapy. Finally, we discuss the possible pitfalls, side effects and cellular escape mechanisms that need to be considered in the process of translating the plethora of basic research data into a clinical setting.
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Affiliation(s)
- Christian Stock
- Department of Gastroenterology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
| | - Stine Falsig Pedersen
- Department of Biology, Section for Cell Biology and Physiology, University of Copenhagen, Universitetsparken 13, 2100 Copenhagen, Denmark.
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32
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Changede R, Sheetz M. Integrin and cadherin clusters: A robust way to organize adhesions for cell mechanics. Bioessays 2016; 39:1-12. [PMID: 27930828 DOI: 10.1002/bies.201600123] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recent studies at the nanometer scale have revealed that relatively uniform clusters of adhesion proteins (50-100 nm) constitute the modular units of cell adhesion sites in both cell-matrix and cell-cell adhesions. Super resolution microscopy and membrane protein diffusion studies both suggest that even large focal adhesions are formed of 100 nm clusters that are loosely aggregated. Clusters of 20-50 adhesion molecules (integrins or cadherins) can support large forces through avidity binding interactions but can also be disassembled or endocytosed rapidly. Assembly of the clusters of integrins is force-independent and involves gathering integrins at ligand binding sites where they are stabilized by cytoplasmic adhesion proteins that crosslink the integrin cytoplasmic tails plus connect the clusters to the cell cytoskeleton. Cooperative-signaling events can occur in a single cluster without cascading to other clusters. Thus, the clusters appear to be very important elements in many cellular processes and can be considered as a critical functional module.
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Affiliation(s)
- Rishita Changede
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
| | - Michael Sheetz
- Mechanobiology Institute, National University of Singapore, Singapore, Singapore
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33
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Sessions JW, Lewis TE, Skousen CS, Hope S, Jensen BD. The effect of injection speed and serial injection on propidium iodide entry into cultured HeLa and primary neonatal fibroblast cells using lance array nanoinjection. SPRINGERPLUS 2016; 5:1093. [PMID: 27468394 PMCID: PMC4947087 DOI: 10.1186/s40064-016-2757-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 07/05/2016] [Indexed: 01/01/2023]
Abstract
Background Although site-directed genetic engineering has greatly improved in recent years, particularly with the implementation of CRISPR-Cas9, the ability to deliver these molecular constructs to a wide variety of cell types without adverse reaction is still a challenge. One non-viral transfection method designed to address this challenge is a MEMS based biotechnology described previously as lance array nanoinjection (LAN). LAN delivery of molecular loads is based upon the combinational use of electrical manipulation of loads of interest and physical penetration of target cell membranes. This work explores an original procedural element to nanoinjection by investigating the effects of the speed of injection and also the ability to serially inject the same sample. Results Initial LAN experimentation demonstrated that injecting at speeds of 0.08 mm/s resulted in 99.3 % of cultured HeLa 229 cells remaining adherent to the glass slide substrate used to stage the injection process. These results were then utilized to examine whether or not target cells could be injected multiple times (1, 2, and 3 times) since the injection process was not pulling the cells off of the glass slide. Using two different current control settings (1.5 and 3.0 mA) and two different cell types (HeLa 229 cells and primary neonatal fibroblasts [BJ(ATCC® CRL-2522™)], treatment samples were injected with propidium iodide (PI), a cell membrane impermeable nucleic acid dye, to assess the degree of molecular load delivery. Results from the serial injection work indicate that HeLa cells treated with 3.0 mA and injected twice (×2) had the greatest mean PI uptake of 60.47 % and that neonatal fibroblasts treated with the same protocol reached mean PI uptake rates of 20.97 %. Conclusions Both experimental findings are particularly useful because it shows that greater molecular modification rates can be achieved by multiple, serial injections via a slower injection process.
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Affiliation(s)
- John W Sessions
- Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602 USA
| | - Tyler E Lewis
- Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602 USA
| | - Craig S Skousen
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT 84602 USA
| | - Sandra Hope
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, UT 84602 USA
| | - Brian D Jensen
- Department of Mechanical Engineering, Brigham Young University, Provo, UT 84602 USA
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Huff JL, Lynch MP, Nettikadan S, Johnson JC, Vengasandra S, Henderson E. Label-Free Protein and Pathogen Detection Using the Atomic Force Microscope. ACTA ACUST UNITED AC 2016; 9:491-7. [PMID: 15452335 DOI: 10.1177/1087057104268803] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The atomic force microscope (AFM) uses a sharp micron-scale tip to scan and amplify surface features, providing exceptionally detailed topographical information with magnification on the order of ×106. This instrument is used extensively for quality control in the computer and semiconductor industries and is becoming a progressively more important tool in the biological sciences. Advantages of the AFM for biological application include the ability to obtain information in a direct, label-free manner and the ability to image in solution, providing real-time data acquisition under physiologically relevant conditions. A novel application of the AFM currently under development combines its surface profiling capabilities with fixed immuno-capture using antibodies immobilized in a nanoarray format. This provides a distinctive platform for direct, label-free detection and characterization of viral particles and other pathogens.
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35
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In vitro model of bone to facilitate measurement of adhesion forces and super-resolution imaging of osteoclasts. Sci Rep 2016; 6:22585. [PMID: 26935172 PMCID: PMC4776281 DOI: 10.1038/srep22585] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 02/18/2016] [Indexed: 11/08/2022] Open
Abstract
To elucidate processes in the osteoclastic bone resorption, visualise resorption and related actin reorganisation, a combination of imaging technologies and an applicable in vitro model is needed. Nanosized bone powder from matching species is deposited on any biocompatible surface in order to form a thin, translucent, smooth and elastic representation of injured bone. Osteoclasts cultured on the layer expressed matching morphology to ones cultured on sawed cortical bone slices. Resorption pits were easily identified by reflectance microscopy. The coating allowed actin structures on the bone interface to be visualised with super-resolution microscopy along with a detailed interlinked actin networks and actin branching in conjunction with V-ATPase, dynamin and Arp2/3 at actin patches. Furthermore, we measured the timescale of an adaptive osteoclast adhesion to bone by force spectroscopy experiments on live osteoclasts with bone-coated AFM cantilevers. Utilising the in vitro model and the advanced imaging technologies we localised immunofluorescence signals in respect to bone with high precision and detected resorption at its early stages. Put together, our data supports a cyclic model for resorption in human osteoclasts.
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36
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Kim H, Lee J. Strategies to Maximize the Potential of Marine Biomaterials as a Platform for Cell Therapy. Mar Drugs 2016; 14:E29. [PMID: 26821034 PMCID: PMC4771982 DOI: 10.3390/md14020029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 01/15/2016] [Accepted: 01/19/2016] [Indexed: 01/31/2023] Open
Abstract
Marine biopolymers have been explored as a promising cell therapy system for efficient cell delivery and tissue engineering. However, the marine biomaterial-based systems themselves have exhibited limited performance in terms of maintenance of cell viability and functions, promotion of cell proliferation and differentiation as well as cell delivery efficiency. Thus, numerous novel strategies have been devised to improve cell therapy outcomes. The strategies include optimization of physical and biochemical properties, provision of stimuli-responsive functions, and design of platforms for efficient cell delivery and tissue engineering. These approaches have demonstrated substantial improvement of therapeutic outcomes in a variety of research settings. In this review, therefore, research progress made with marine biomaterials as a platform for cell therapy is reported along with current research directions to further advance cell therapies as a tool to cure incurable diseases.
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Affiliation(s)
- Hyeongmin Kim
- Pharmaceutical Formulation Design Laboratory, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea.
- Bio-Integration Research Center for Nutra-Pharmaceutical Epigenetics, Chung-Ang University, Seoul 156-756, Korea.
| | - Jaehwi Lee
- Pharmaceutical Formulation Design Laboratory, College of Pharmacy, Chung-Ang University, Seoul 156-756, Korea.
- Bio-Integration Research Center for Nutra-Pharmaceutical Epigenetics, Chung-Ang University, Seoul 156-756, Korea.
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37
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Jurchenko C, Salaita KS. Lighting Up the Force: Investigating Mechanisms of Mechanotransduction Using Fluorescent Tension Probes. Mol Cell Biol 2015; 35:2570-82. [PMID: 26031334 PMCID: PMC4524122 DOI: 10.1128/mcb.00195-15] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The ability of cells to sense the physical nature of their surroundings is critical to the survival of multicellular organisms. Cellular response to physical cues from adjacent cells and the extracellular matrix leads to a dynamic cycle in which cells respond by remodeling their local microenvironment, fine-tuning cell stiffness, polarity, and shape. Mechanical regulation is important in cellular development, normal morphogenesis, and wound healing. The mechanisms by which these finely balanced mechanotransduction events occur, however, are not well understood. In large part, this is due to the limited availability of tools to study molecular mechanotransduction events in live cells. Several classes of molecular tension probes have been recently developed which are rapidly transforming the study of mechanotransduction. Molecular tension probes are primarily based on fluorescence resonance energy transfer (FRET) and report on piconewton scale tension events in live cells. In this minireview, we describe the two main classes of tension probes, genetically encoded tension sensors and immobilized tension sensors, and discuss the advantages and limitations of each type. We discuss future opportunities to address major biological questions and outline the challenges facing the next generation of molecular tension probes.
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Affiliation(s)
- Carol Jurchenko
- Department of Chemistry, Emory University, Atlanta, Georgia, USA
| | - Khalid S Salaita
- Department of Chemistry, Emory University, Atlanta, Georgia, USA
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Eleta-Lopez A, Etxebarria J, Reichardt NC, Georgieva R, Bäumler H, Toca-Herrera JL. On the molecular interaction between albumin and ibuprofen: An AFM and QCM-D study. Colloids Surf B Biointerfaces 2015. [PMID: 26218522 DOI: 10.1016/j.colsurfb.2015.06.063] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The adsorption of proteins on surfaces often results in a change of their structural behavior and consequently, a loss of bioactivity. One experimental method to study interactions on a molecular level is single molecular force spectroscopy that permits to measure forces down to the pico-newton range. In this work, the binding force between human serum albumin (HSA), covalently immobilized on glutaraldehyde modified gold substrates, and ibuprofen sodium salt was studied by means of single molecular force spectroscopy. First of all, a protocol was established to functionalize atomic force microscopy (AFM) tips with ibuprofen. The immobilization protocol was additionally tested by quartz crystal microbalance with dissipation (QCM-D) and contact angle measurements. AFM was used to characterize the adsorption of HSA on gold substrates, which lead to a packed monolayer of thickness slightly lower than the reported value in solution. Finally, single molecule spectroscopy results were used to characterize the binding force between albumin and ibuprofen and calculate the distance of the transition state (0.6 nm) and the dissociation rate constant (0.055 s(-1)). The results might indicate that part of the adsorbed protein still preserves its functionality upon adsorption.
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Affiliation(s)
- Aitziber Eleta-Lopez
- CIC nanoGUNE Consolider, Tolosa Hiribidea 20018 Donostia/San Sebastian, Spain; Biosurfaces Unit, CIC biomaGUNE, Miramon Pasealekua 182, 20009 Donostia/San Sebastian, Spain.
| | - Juan Etxebarria
- Biofunctional Nanomaterials Unit, CIC biomaGUNE, Miramon Pasealekua 182, 20009 Donostia/San Sebastian, Spain
| | - Niels-Christian Reichardt
- Biofunctional Nanomaterials Unit, CIC biomaGUNE, Miramon Pasealekua 182, 20009 Donostia/San Sebastian, Spain; CIBER-BBN, Miramon Pasealekua 182, 20009 Donostia/San Sebastian, Spain
| | - Radostina Georgieva
- Charité-Universitätsmedizin Berlin, Institute of Transfusion Medicine, Charitéplatz 1, 10117 Berlin, Germany; Department of Medical Physics, Biophysics and Radiology, Medical Faculty, Trakia University,, ul. Armeiska 11, 6000 Stara Zagora, Bulgaria
| | - Hans Bäumler
- Charité-Universitätsmedizin Berlin, Institute of Transfusion Medicine, Charitéplatz 1, 10117 Berlin, Germany
| | - José L Toca-Herrera
- Biosurfaces Unit, CIC biomaGUNE, Miramon Pasealekua 182, 20009 Donostia/San Sebastian, Spain; Institute for Biophysics, Department of Nanobiotechnology, University of Natural Resources and Life Sciences Vienna (BOKU), Muthgasse 11, A-1190 Vienna, Austria.
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Kim DY, Park H, Lee KY. Effect of the Mechanical Properties of Cell-Interactive Hydrogels on a Control of Cell Phenotype. POLYMER-KOREA 2015. [DOI: 10.7317/pk.2015.39.3.412] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Saito M, Watanabe-Nakayama T, Machida S, Osada T, Afrin R, Ikai A. Spectrin-ankyrin interaction mechanics: A key force balance factor in the red blood cell membrane skeleton. Biophys Chem 2015; 200-201:1-8. [PMID: 25866912 DOI: 10.1016/j.bpc.2015.03.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 03/19/2015] [Accepted: 03/22/2015] [Indexed: 12/31/2022]
Abstract
As major components of red blood cell (RBC) cytoskeleton, spectrin and F-actin form a network that covers the entire cytoplasmic surface of the plasma membrane. The cross-linked two layered structure, called the membrane skeleton, keeps the structural integrity of RBC under drastically changing mechanical environment during circulation. We performed force spectroscopy experiments on the atomic force microscope (AFM) as a means to clarify the mechanical characteristics of spectrin-ankyrin interaction, a key factor in the force balance of the RBC cytoskeletal structure. An AFM tip was functionalized with ANK1-62k and used to probe spectrin crosslinked to mica surface. A force spectroscopy study gave a mean unbinding force of ~30 pN under our experimental conditions. Two energy barriers were identified in the unbinding process. The result was related to the well-known flexibility of spectrin tetramer and participation of ankyrin 1-spectrin interaction in the overall balance of membrane skeleton dynamics.
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Affiliation(s)
- Masakazu Saito
- Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan.
| | - Takahiro Watanabe-Nakayama
- Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| | - Shinichi Machida
- Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| | - Toshiya Osada
- Depertment of Life Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, B-2 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| | - Rehana Afrin
- Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan; Biofrontier Center, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
| | - Atsushi Ikai
- Innovation Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa 226-8501, Japan
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Hong Z, Reeves KJ, Sun Z, Li Z, Brown NJ, Meininger GA. Vascular smooth muscle cell stiffness and adhesion to collagen I modified by vasoactive agonists. PLoS One 2015; 10:e0119533. [PMID: 25745858 PMCID: PMC4351978 DOI: 10.1371/journal.pone.0119533] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2014] [Accepted: 01/22/2015] [Indexed: 11/25/2022] Open
Abstract
In vascular smooth muscle cells (VSMCs) integrin-mediated adhesion to extracellular matrix (ECM) proteins play important roles in sustaining vascular tone and resistance. The main goal of this study was to determine whether VSMCs adhesion to type I collagen (COL-I) was altered in parallel with the changes in the VSMCs contractile state induced by vasoconstrictors and vasodilators. VSMCs were isolated from rat cremaster skeletal muscle arterioles and maintained in primary culture without passage. Cell adhesion and cell E-modulus were assessed using atomic force microscopy (AFM) by repetitive nano-indentation of the AFM probe on the cell surface at 0.1 Hz sampling frequency and 3200 nm Z-piezo travelling distance (approach and retraction). AFM probes were tipped with a 5 μm diameter microbead functionalized with COL-I (1mg\ml). Results showed that the vasoconstrictor angiotensin II (ANG-II; 10−6) significantly increased (p<0.05) VSMC E-modulus and adhesion probability to COL-I by approximately 35% and 33%, respectively. In contrast, the vasodilator adenosine (ADO; 10−4) significantly decreased (p<0.05) VSMC E-modulus and adhesion probability by approximately −33% and −17%, respectively. Similarly, the NO donor (PANOate, 10−6 M), a potent vasodilator, also significantly decreased (p<0.05) the VSMC E-modulus and COL-I adhesion probability by −38% and −35%, respectively. These observations support the hypothesis that integrin-mediated VSMC adhesion to the ECM protein COL-I is dynamically regulated in parallel with VSMC contractile activation. These data suggest that the signal transduction pathways modulating VSMC contractile activation and relaxation, in addition to ECM adhesion, interact during regulation of contractile state.
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Affiliation(s)
- Zhongkui Hong
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Pharmacology and Physiology, University of Missouri, Columbia, Missouri, United States of America
| | - Kimberley J. Reeves
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States of America
| | - Zhe Sun
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Pharmacology and Physiology, University of Missouri, Columbia, Missouri, United States of America
| | - Zhaohui Li
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States of America
| | - Nicola J. Brown
- Department of Oncology, University of Sheffield, Sheffield, United Kingdom
| | - Gerald A. Meininger
- Dalton Cardiovascular Research Center, University of Missouri, Columbia, Missouri, United States of America
- Department of Pharmacology and Physiology, University of Missouri, Columbia, Missouri, United States of America
- * E-mail:
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42
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Stock C, Schwab A. Ion channels and transporters in metastasis. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1848:2638-46. [PMID: 25445667 DOI: 10.1016/j.bbamem.2014.11.012] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2014] [Revised: 11/03/2014] [Accepted: 11/07/2014] [Indexed: 12/23/2022]
Abstract
An elaborate interplay between ion channels and transporters, components of the cytoskeleton, adhesion molecules, and signaling cascades provides the basis for each major step of the metastatic cascade. Ion channels and transporters contribute to cell motility by letting through or transporting ions essential for local Ca2+, pH and--in cooperation with water permeable aquaporins--volume homeostasis. Moreover, in addition to the actual ion transport they, or their auxiliary subunits, can display non-conducting activities. They can exert kinase activity in order to phosphorylate cytoskeletal constituents or their associates. They can become part of signaling processes by permeating Ca2+, by generating local pH-nanodomains or by being final downstream effectors. A number of channels and transporters are found at focal adhesions, interacting directly or indirectly with proteins of the extracellular matrix, with integrins or with components of the cytoskeleton. We also include the role of aquaporins in cell motility. They drive the outgrowth of lamellipodia/invadopodia or control the number of β1 integrins in the plasma membrane. The multitude of interacting ion channels and transporters (called transportome) including the associated signaling events holds great potential as therapeutic target(s) for anticancer agents that are aimed at preventing metastasis. This article is part of a Special Issue entitled: Membrane channels and transporters in cancers.
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Affiliation(s)
- Christian Stock
- Department of Gastroenterology, Hannover Medical School, Hannover, Germany.
| | - Albrecht Schwab
- Institute of Physiology II, University of Münster, Robert-Koch-Str. 27b, D-48149 Münster, Germany
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43
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Jurchenko C, Chang Y, Narui Y, Zhang Y, Salaita KS. Integrin-generated forces lead to streptavidin-biotin unbinding in cellular adhesions. Biophys J 2014; 106:1436-46. [PMID: 24703305 DOI: 10.1016/j.bpj.2014.01.049] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 12/20/2013] [Accepted: 01/29/2014] [Indexed: 11/18/2022] Open
Abstract
The interplay between chemical and mechanical signals plays an important role in cell biology, and integrin receptors are the primary molecules involved in sensing and transducing external mechanical cues. We used integrin-specific probes in molecular tension fluorescence microscopy to investigate the pN forces exerted by integrin receptors in living cells. The molecular tension fluorescence microscopy probe consisted of a cyclic Arg-Gly-Asp-D-Phe-Lys(Cys) (cRGDfK(C)) peptide tethered to the terminus of a polyethylene glycol polymer that was attached to a surface through streptavidin-biotin linkage. A fluorescence resonance energy transfer mechanism was used to visualize tension-driven extension of the polymer. Surprisingly, we found that integrin receptors dissociate streptavidin-biotin tethered ligands in focal adhesions within 60 min of cell seeding. Although streptavidin-biotin binding affinity is described as the strongest noncovalent bond in nature, and is ~10(6) - 10(8) times larger than that of integrin-RGD affinity, our results suggest that individual integrin-ligand complexes undergo a marked enhancement in stability when the receptor assembles in the cell membrane. Based on the observation of streptavidin-biotin unbinding, we also conclude that the magnitude of integrin-ligand tension in focal adhesions can reach values that are at least 10 fold larger than was previously estimated using traction force microscopy-based methods.
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Affiliation(s)
| | - Yuan Chang
- Department of Chemistry, Emory University, Atlanta, Georgia
| | - Yoshie Narui
- Department of Chemistry, Emory University, Atlanta, Georgia
| | - Yun Zhang
- Department of Chemistry, Emory University, Atlanta, Georgia
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44
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Brito IR, Lima IMT, Xu M, Shea LD, Woodruff TK, Figueiredo JR. Three-dimensional systems for in vitro follicular culture: overview of alginate-based matrices. Reprod Fertil Dev 2014; 26:915-30. [PMID: 23866836 PMCID: PMC11287383 DOI: 10.1071/rd12401] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 06/12/2013] [Indexed: 08/01/2024] Open
Abstract
The in vitro culture of ovarian follicles has provided critical insight into the biology of the follicle and its enclosed oocyte and the physical interaction and communication between the theca and granulosa cells and the oocyte that is necessary to produce meiotically competent oocytes. Various two-dimensional (2D) and three-dimensional (3D) culture systems have been developed to evaluate the effect of growth factors, hormones, extracellular matrix components and culture conditions on follicle development and oocyte growth and maturation. Among these culture systems, 3D systems make it possible to maintain follicle structure and support communication between the various cell compartments within the follicle. In this review article, we will discuss the three main approaches to ovarian follicle culture: 2D attachment systems, 3D floating systems and 3D encapsulated systems. We will specifically emphasise the development of and advances in alginate-based encapsulated systems for in vitro follicle culture.
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Affiliation(s)
- Ivina R. Brito
- Faculty of Veterinary, Laboratory of Manipulation of Oocyte and Preantral Follicles (LAMOFOPA), PPGCV, State University of Ceará, Fortaleza, CE 60740-930, Brazil
| | | | - Min Xu
- Division of Reproductive Biology and Clinical Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago IL, 60611, USA
| | - Lonnie D. Shea
- Division of Reproductive Biology and Clinical Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago IL, 60611, USA
| | - Teresa K. Woodruff
- Division of Reproductive Biology and Clinical Research, Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago IL, 60611, USA
| | - José R. Figueiredo
- Faculty of Veterinary, Laboratory of Manipulation of Oocyte and Preantral Follicles (LAMOFOPA), PPGCV, State University of Ceará, Fortaleza, CE 60740-930, Brazil
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45
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Xie H, Yin M, Rong W, Sun L. In situ quantification of living cell adhesion forces: single cell force spectroscopy with a nanotweezer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2014; 30:2952-2959. [PMID: 24571680 DOI: 10.1021/la500045q] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A novel method is presented for in situ quantification of living cell adhesion forces using a homemade nanorobotic system provided with two independently actuated probes that form a dual-probe nanotweezer capable of pick-and-place manipulation of a single living cell in an aqueous environment. Compared with single-cell force spectroscopy (SCFS) based on traditional atomic force microscopy (AFM), cell immobilization via chemical trapping is unnecessary and the test cell can be efficiently released using the nanotweezer to significantly enhance production of the SCFS. Benefiting from the accurate force sensing capability of AFM, the nanotweezer allows reliable force measurement ranging from picoNewtons to microNewtons and is sufficiently sensitive to characterize short- and long-term adhesion of cell-cell and cell-substrate adhesions. Capabilities of the nanotweezer have been validated through experimental qualification of cell-substrate and cell-cell adhesion events of C2C12 cells (mouse myoblast adherent) with different contact times.
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Affiliation(s)
- Hui Xie
- The State Key Laboratory of Robotics and Systems, Harbin Institute of Technology , 2 Yikuang, C1 HIT Science Park, 150080 Harbin, China
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46
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Schwab A, Stock C. Ion channels and transporters in tumour cell migration and invasion. Philos Trans R Soc Lond B Biol Sci 2014; 369:20130102. [PMID: 24493750 DOI: 10.1098/rstb.2013.0102] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Cell migration is a central component of the metastatic cascade requiring a concerted action of ion channels and transporters (migration-associated transportome), cytoskeletal elements and signalling cascades. Ion transport proteins and aquaporins contribute to tumour cell migration and invasion among other things by inducing local volume changes and/or by modulating Ca(2+) and H(+) signalling. Targeting cell migration therapeutically bears great clinical potential, because it is a prerequisite for metastasis. Ion transport proteins appear to be attractive candidate target proteins for this purpose because they are easily accessible as membrane proteins and often overexpressed or activated in cancer. Importantly, a number of clinically widely used drugs are available whose anticipated efficacy as anti-tumour drugs, however, has now only begun to be evaluated.
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Affiliation(s)
- Albrecht Schwab
- Institut für Physiologie II, Westfälische Wilhelms-Universität Münster, , Robert-Koch-Strasse 27b, Münster 48149, Germany
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Measurement of cationic and intracellular modulation of integrin binding affinity by AFM-based nanorobot. Biophys J 2014; 105:40-7. [PMID: 23823222 DOI: 10.1016/j.bpj.2013.05.052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 05/12/2013] [Accepted: 05/30/2013] [Indexed: 11/23/2022] Open
Abstract
Integrins are dynamic transmembrane cation-dependent heterodimers that both anchor cells in position and transduce signals into and out of cells. We used an atomic force microscope (AFM)-based nanorobotic system to measure integrin-binding forces in intact human intestinal epithelial Caco-2 cells. The AFM-based nanorobot enables human-directed, high-accuracy probe positioning and site-specific investigations. Functionalizing the AFM probe with an arginine-glycine-aspartate (RGD)-containing sequence (consensus binding sequence for integrins) allowed us to detect a series of peptide-cell membrane interactions with a median binding force of 115.1 ± 4.9 pN that were not detected in control interactions. Chelating divalent cations from the culture medium abolished these interactions, as did inhibiting intracellular focal adhesion kinase (FAK) using Y15. Adding 1 mM Mg(2+) to the medium caused a rightward shift in the force-binding curve. Adding 1 mM Ca(2+) virtually abolished the RGD-membrane specific interactions and blocked the Mg(2+) effects. Cell adhesion assays demonstrated parallel effects of divalent cations and the FAK inhibitor on cell adhesion. These results demonstrate direct modulation of integrin-binding affinity by both divalent cations and intracellular signal inhibition. Additionally, three binding states (nonspecific, specific inactivated, and specific activated) were delineated from affinity measurements. Although other research has assumed that this process of integrin conformational change causes altered ligand binding, in this work we directly measured these three states in individual integrins in a physiologically based study.
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Hong Z, Sun Z, Li M, Li Z, Bunyak F, Ersoy I, Trzeciakowski JP, Staiculescu MC, Jin M, Martinez-Lemus L, Hill MA, Palaniappan K, Meininger GA. Vasoactive agonists exert dynamic and coordinated effects on vascular smooth muscle cell elasticity, cytoskeletal remodelling and adhesion. J Physiol 2014; 592:1249-66. [PMID: 24445320 DOI: 10.1113/jphysiol.2013.264929] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
In this study, we examined the ability of vasoactive agonists to induce dynamic changes in vascular smooth muscle cell (VSMC) elasticity and adhesion, and tested the hypothesis that these events are coordinated with rapid remodelling of the cortical cytoskeleton. Real-time measurement of cell elasticity was performed with atomic force microscopy (AFM) and adhesion was assessed with AFM probes coated with fibronectin (FN). Temporal data were analysed using an Eigen-decomposition method. Elasticity in VSMCs displayed temporal oscillations with three components at approximately 0.001, 0.004 and 0.07 Hz, respectively. Similarly, adhesion displayed a similar oscillatory pattern. Angiotensin II (ANG II, 10(-6) M) increased (+100%) the amplitude of the oscillations, whereas the vasodilator adenosine (ADO, 10(-4) M) reduced oscillation amplitude (-30%). To test whether the oscillatory changes were related to the architectural alterations in cortical cytoskeleton, the topography of the submembranous actin cytoskeleton (100-300 nm depth) was acquired with AFM. These data were analysed to compare cortical actin fibre distribution and orientation before and after treatment with vasoactive agonists. The results showed that ANG II increased the density of stress fibres by 23%, while ADO decreased the density of the stress fibres by 45%. AFM data were supported by Western blot and confocal microscopy. Collectively, these observations indicate that VSMC cytoskeletal structure and adhesion to the extracellular matrix are dynamically altered in response to agonist stimulation. Thus, vasoactive agonists probably invoke unique mechanisms that dynamically alter the behaviour and structure of both the VSMC cytoskeleton and focal adhesions to efficiently support the normal contractile behaviour of VSMCs.
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Affiliation(s)
- Zhongkui Hong
- Dalton Cardiovascular Center, University of Missouri, 134 Research Park Dr., Columbia, MO 65211, USA.
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Senapati S, Manna S, Lindsay S, Zhang P. Application of catalyst-free click reactions in attaching affinity molecules to tips of atomic force microscopy for detection of protein biomarkers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:14622-30. [PMID: 24180289 PMCID: PMC3886287 DOI: 10.1021/la4039667] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Atomic force microscopy (AFM) has been extensively used in studies of biological interactions. Particularly, AFM based force spectroscopy and recognition imaging can sense biomolecules on a single molecule level, having great potential to become a tool for molecular diagnostics in clinics. These techniques, however, require affinity molecules to be attached to AFM tips in order to specifically detect their targets. The attachment chemistry currently used on silicon tips involves multiple steps of reactions and moisture sensitive chemicals, such as (3-aminopropyl)triethoxysilane (APTES) and N-hydroxysuccinimide (NHS) ester, making the process difficult to operate in aqueous solutions. In the present study, we have developed a user-friendly protocol to functionalize the AFM tips with affinity molecules. A key feature of it is that all reactions are carried out in aqueous solutions. In summary, we first synthesized a molecular anchor composed of cyclooctyne and silatrane for introduction of a chemically reactive function to AFM tips and a bifunctional polyethylene glycol linker that harnesses two orthogonal click reactions, copper free alkyne-azide cycloaddition and thiol-vinylsulfone Michael addition, for attaching affinity molecules to AFM tips. The attachment chemistry was then validated by attaching antithrombin DNA aptamers and cyclo-RGD peptides to silicon nitride (SiN) tips, respectively, and measuring forces of unbinding these affinity molecules from their protein cognates human α-thrombin and human α5β1-integrin immobilized on mica surfaces. In turn, we used the same attachment chemistry to functionalize silicon tips with the same affinity molecules for AFM based recognition imaging, showing that the disease-relevant biomarkers such as α-thrombin and α5β1-integrin can be detected with high sensitivity and specificity by the single molecule technique. These studies demonstrate the feasibility of our attachment chemistry for the use in functionalization of AFM tips with affinity molecules.
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Affiliation(s)
- Subhadip Senapati
- Center for Single Molecule Biophysics of the Biodesign Institute, Arizona State University, Tempe, Arizona 85287, USA
| | - Saikat Manna
- Center for Single Molecule Biophysics of the Biodesign Institute, Arizona State University, Tempe, Arizona 85287, USA
| | - Stuart Lindsay
- Center for Single Molecule Biophysics of the Biodesign Institute, Arizona State University, Tempe, Arizona 85287, USA
| | - Peiming Zhang
- Center for Single Molecule Biophysics of the Biodesign Institute, Arizona State University, Tempe, Arizona 85287, USA
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50
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Stock C, Ludwig FT, Hanley PJ, Schwab A. Roles of ion transport in control of cell motility. Compr Physiol 2013; 3:59-119. [PMID: 23720281 DOI: 10.1002/cphy.c110056] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cell motility is an essential feature of life. It is essential for reproduction, propagation, embryonic development, and healing processes such as wound closure and a successful immune defense. If out of control, cell motility can become life-threatening as, for example, in metastasis or autoimmune diseases. Regardless of whether ciliary/flagellar or amoeboid movement, controlled motility always requires a concerted action of ion channels and transporters, cytoskeletal elements, and signaling cascades. Ion transport across the plasma membrane contributes to cell motility by affecting the membrane potential and voltage-sensitive ion channels, by inducing local volume changes with the help of aquaporins and by modulating cytosolic Ca(2+) and H(+) concentrations. Voltage-sensitive ion channels serve as voltage detectors in electric fields thus enabling galvanotaxis; local swelling facilitates the outgrowth of protrusions at the leading edge while local shrinkage accompanies the retraction of the cell rear; the cytosolic Ca(2+) concentration exerts its main effect on cytoskeletal dynamics via motor proteins such as myosin or dynein; and both, the intracellular and the extracellular H(+) concentration modulate cell migration and adhesion by tuning the activity of enzymes and signaling molecules in the cytosol as well as the activation state of adhesion molecules at the cell surface. In addition to the actual process of ion transport, both, channels and transporters contribute to cell migration by being part of focal adhesion complexes and/or physically interacting with components of the cytoskeleton. The present article provides an overview of how the numerous ion-transport mechanisms contribute to the various modes of cell motility.
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Affiliation(s)
- Christian Stock
- Institute of Physiology II, University of Münster, Münster, Germany.
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