1
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Tajvidi Safa B, Huang C, Kabla A, Yang R. Active viscoelastic models for cell and tissue mechanics. ROYAL SOCIETY OPEN SCIENCE 2024; 11:231074. [PMID: 38660600 PMCID: PMC11040246 DOI: 10.1098/rsos.231074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 02/01/2024] [Accepted: 02/25/2024] [Indexed: 04/26/2024]
Abstract
Living cells are out of equilibrium active materials. Cell-generated forces are transmitted across the cytoskeleton network and to the extracellular environment. These active force interactions shape cellular mechanical behaviour, trigger mechano-sensing, regulate cell adaptation to the microenvironment and can affect disease outcomes. In recent years, the mechanobiology community has witnessed the emergence of many experimental and theoretical approaches to study cells as mechanically active materials. In this review, we highlight recent advancements in incorporating active characteristics of cellular behaviour at different length scales into classic viscoelastic models by either adding an active tension-generating element or adjusting the resting length of an elastic element in the model. Summarizing the two groups of approaches, we will review the formulation and application of these models to understand cellular adaptation mechanisms in response to various types of mechanical stimuli, such as the effect of extracellular matrix properties and external loadings or deformations.
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Affiliation(s)
- Bahareh Tajvidi Safa
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE68588, USA
| | - Changjin Huang
- School of Mechanical & Aerospace Engineering, Nanyang Technological University, Singapore639798, Singapore
| | - Alexandre Kabla
- Department of Engineering, University of Cambridge, CambridgeCB2 1PZ, UK
| | - Ruiguo Yang
- Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE68588, USA
- Department of Biomedical Engineering, Michigan State University, East Lansing, MI48824, USA
- Institute for Quantitative Health Science and Engineering (IQ), Michigan State University, East Lansing, MI48824, USA
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2
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Almeida F, Sousa I, Kremer O, da Silva BP, Tasca DS, Khoury AZ, Temporão G, Guerreiro T. Trapping Microparticles in a Structured Dark Focus. PHYSICAL REVIEW LETTERS 2023; 131:163601. [PMID: 37925716 DOI: 10.1103/physrevlett.131.163601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 05/02/2023] [Accepted: 09/11/2023] [Indexed: 11/07/2023]
Abstract
We experimentally demonstrate stable trapping and controlled manipulation of silica microspheres in a structured optical beam consisting of a dark focus surrounded by light in all directions-the dark focus tweezer. Results from power spectrum and potential analysis demonstrate the nonharmonicity of the trapping potential landscape, which is reconstructed from experimental data in agreement to Lorentz-Mie numerical simulations. Applications of the dark tweezer in levitated optomechanics and biophysics are discussed.
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Affiliation(s)
- F Almeida
- Departamento de Física, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro, RJ, Brazil
| | - I Sousa
- Departamento de Física, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro, RJ, Brazil
| | - O Kremer
- Centro de Estudos em Telecomunicações, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro, RJ, Brazil
| | - B Pinheiro da Silva
- Instituto de Física, Universidade Federal Fluminense, Niterói, Rio de Janeiro 24210-346, Brazil
| | - D S Tasca
- Instituto de Física, Universidade Federal Fluminense, Niterói, Rio de Janeiro 24210-346, Brazil
| | - A Z Khoury
- Instituto de Física, Universidade Federal Fluminense, Niterói, Rio de Janeiro 24210-346, Brazil
| | - G Temporão
- Centro de Estudos em Telecomunicações, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro, RJ, Brazil
| | - T Guerreiro
- Departamento de Física, Pontifícia Universidade Católica do Rio de Janeiro, 22451-900 Rio de Janeiro, RJ, Brazil
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3
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Wang Y, Chen J, Su G, Mei J, Li J. A Review of Single-Cell Microrobots: Classification, Driving Methods and Applications. MICROMACHINES 2023; 14:1710. [PMID: 37763873 PMCID: PMC10537272 DOI: 10.3390/mi14091710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/19/2023] [Accepted: 08/23/2023] [Indexed: 09/29/2023]
Abstract
Single-cell microrobots are new microartificial devices that use a combination of single cells and artificial devices, with the advantages of small size, easy degradation and ease of manufacture. With externally driven strategies such as light fields, sound fields and magnetic fields, microrobots are able to carry out precise micromanipulations and movements in complex microenvironments. Therefore, single-cell microrobots have received more and more attention and have been greatly developed in recent years. In this paper, we review the main classifications, control methods and recent advances in the field of single-cell microrobot applications. First, different types of robots, such as cell-based microrobots, bacteria-based microrobots, algae-based microrobots, etc., and their design strategies and fabrication processes are discussed separately. Next, three types of external field-driven technologies, optical, acoustic and magnetic, are presented and operations realized in vivo and in vitro by applying these three technologies are described. Subsequently, the results achieved by these robots in the fields of precise delivery, minimally invasive therapy are analyzed. Finally, a short summary is given and current challenges and future work on microbial-based robotics are discussed.
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Affiliation(s)
| | | | | | | | - Junyang Li
- School of Electronic Engineering, Ocean University of China, Qingdao 266000, China; (Y.W.); (J.C.); (G.S.); (J.M.)
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4
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Zhu Y, Zhang M, Sun Q, Wang X, Li X, Li Q. Advanced Mechanical Testing Technologies at the Cellular Level: The Mechanisms and Application in Tissue Engineering. Polymers (Basel) 2023; 15:3255. [PMID: 37571149 PMCID: PMC10422338 DOI: 10.3390/polym15153255] [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: 07/11/2023] [Revised: 07/24/2023] [Accepted: 07/28/2023] [Indexed: 08/13/2023] Open
Abstract
Mechanics, as a key physical factor which affects cell function and tissue regeneration, is attracting the attention of researchers in the fields of biomaterials, biomechanics, and tissue engineering. The macroscopic mechanical properties of tissue engineering scaffolds have been studied and optimized based on different applications. However, the mechanical properties of the overall scaffold materials are not enough to reveal the mechanical mechanism of the cell-matrix interaction. Hence, the mechanical detection of cell mechanics and cellular-scale microenvironments has become crucial for unraveling the mechanisms which underly cell activities and which are affected by physical factors. This review mainly focuses on the advanced technologies and applications of cell-scale mechanical detection. It summarizes the techniques used in micromechanical performance analysis, including atomic force microscope (AFM), optical tweezer (OT), magnetic tweezer (MT), and traction force microscope (TFM), and analyzes their testing mechanisms. In addition, the application of mechanical testing techniques to cell mechanics and tissue engineering scaffolds, such as hydrogels and porous scaffolds, is summarized and discussed. Finally, it highlights the challenges and prospects of this field. This review is believed to provide valuable insights into micromechanics in tissue engineering.
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Affiliation(s)
- Yingxuan Zhu
- School of Mechanics and Safety Engineering, Zhengzhou University, Zhengzhou 450001, China
- National Center for International Joint Research of Micro-nano Moulding Technology, Zhengzhou University, Zhengzhou 450001, China
| | - Mengqi Zhang
- School of Mechanics and Safety Engineering, Zhengzhou University, Zhengzhou 450001, China
- National Center for International Joint Research of Micro-nano Moulding Technology, Zhengzhou University, Zhengzhou 450001, China
| | - Qingqing Sun
- School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China
| | - Xiaofeng Wang
- School of Mechanics and Safety Engineering, Zhengzhou University, Zhengzhou 450001, China
- National Center for International Joint Research of Micro-nano Moulding Technology, Zhengzhou University, Zhengzhou 450001, China
| | - Xiaomeng Li
- School of Mechanics and Safety Engineering, Zhengzhou University, Zhengzhou 450001, China
- National Center for International Joint Research of Micro-nano Moulding Technology, Zhengzhou University, Zhengzhou 450001, China
| | - Qian Li
- School of Mechanics and Safety Engineering, Zhengzhou University, Zhengzhou 450001, China
- National Center for International Joint Research of Micro-nano Moulding Technology, Zhengzhou University, Zhengzhou 450001, China
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5
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Abstract
Plasma membrane tension functions as a global physical organizer of cellular activities. Technical limitations of current membrane tension measurement techniques have hampered in-depth investigation of cellular membrane biophysics and the role of plasma membrane tension in regulating cellular processes. Here, we develop an optical membrane tension reporter by repurposing an E. coli mechanosensitive channel via insertion of circularly permuted GFP (cpGFP), which undergoes a large conformational rearrangement associated with channel activation and thus fluorescence intensity changes under increased membrane tension.
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Affiliation(s)
- Yen-Yu Hsu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Agnes M Resto Irizarry
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jianping Fu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Allen P Liu
- Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Biophysics, University of Michigan, Ann Arbor, Michigan 48109, United States
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, Michigan 48109, United States
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6
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Cheppali SK, Dharan R, Sorkin R. Forces of Change: Optical Tweezers in Membrane Remodeling Studies. J Membr Biol 2022; 255:677-690. [PMID: 35616705 DOI: 10.1007/s00232-022-00241-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 04/22/2022] [Indexed: 12/24/2022]
Abstract
Optical tweezers allow precise measurement of forces and distances with piconewton and nanometer precision, and have thus been instrumental in elucidating the mechanistic details of various biological processes. Some examples include the characterization of motor protein activity, studies of protein-DNA interactions, and characterizing protein folding trajectories. The use of optical tweezers (OT) to study membranes is, however, much less abundant. Here, we review biophysical studies of membranes that utilize optical tweezers, with emphasis on various assays that have been developed and their benefits and limitations. First, we discuss assays that employ membrane-coated beads, and overview protein-membrane interactions studies based on manipulation of such beads. We further overview a body of studies that make use of a very powerful experimental tool, the combination of OT, micropipette aspiration, and fluorescence microscopy, that allow detailed studies of membrane curvature generation and sensitivity. Finally, we describe studies focused on membrane fusion and fission. We then summarize the overall progress in the field and outline future directions.
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Affiliation(s)
- Sudheer K Cheppali
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, Israel.,Center for Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel.,Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv, Israel.,Center for Light-Matter Interaction, Tel Aviv University, Tel Aviv, Israel
| | - Raviv Dharan
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, Israel.,Center for Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel.,Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv, Israel.,Center for Light-Matter Interaction, Tel Aviv University, Tel Aviv, Israel
| | - Raya Sorkin
- Raymond and Beverly Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Tel Aviv, Israel. .,Center for Physics and Chemistry of Living Systems, Tel Aviv University, Tel Aviv, Israel. .,Center for Nanoscience and Nanotechnology, Tel Aviv University, Tel Aviv, Israel. .,Center for Light-Matter Interaction, Tel Aviv University, Tel Aviv, Israel.
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7
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Favre-Bulle IA, Scott EK. Optical tweezers across scales in cell biology. Trends Cell Biol 2022; 32:932-946. [PMID: 35672197 PMCID: PMC9588623 DOI: 10.1016/j.tcb.2022.05.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 05/02/2022] [Accepted: 05/04/2022] [Indexed: 01/21/2023]
Abstract
Optical tweezers (OT) provide a noninvasive approach for delivering minute physical forces to targeted objects. Controlling such forces in living cells or in vitro preparations allows for the measurement and manipulation of numerous processes relevant to the form and function of cells. As such, OT have made important contributions to our understanding of the structures of proteins and nucleic acids, the interactions that occur between microscopic structures within cells, the choreography of complex processes such as mitosis, and the ways in which cells interact with each other. In this review, we highlight recent contributions made to the field of cell biology using OT and provide basic descriptions of the physics, the methods, and the equipment that made these studies possible.
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Affiliation(s)
- Itia A Favre-Bulle
- Queensland Brain Institute, The University of Queensland, 4067, Brisbane, Australia; School of Mathematics and Physics, The University of Queensland, 4067, Brisbane, Australia.
| | - Ethan K Scott
- Queensland Brain Institute, The University of Queensland, 4067, Brisbane, Australia; Department of Anatomy and Physiology, School of Biomedical Sciences, The University of Melbourne, Parkville, VIC 3010, Australia.
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8
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Elitas M, Islam M, Korvink JG, Sengul E, Sharbati P, Ozogul B, Kaymaz SV. Quantifying Deformation and Migration Properties of U87 Glioma Cells Using Dielectrophoretic Forces. BIOSENSORS 2022; 12:946. [PMID: 36354455 PMCID: PMC9688500 DOI: 10.3390/bios12110946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 10/27/2022] [Accepted: 10/28/2022] [Indexed: 06/16/2023]
Abstract
Glioblastoma multiforme is one of the most aggressive malignant primary brain tumors. To design effective treatment strategies, we need to better understand the behavior of glioma cells while maintaining their genetic and phenotypic stability. Here, we investigated the deformation and migration profile of U87 Glioma cells under the influence of dielectrophoretic forces. We fabricated a gold microelectrode array within a microfluidic channel and applied sinusoidal wave AC potential at 3 Vpp, ranging from 30 kHz to 10 MHz frequencies, to generate DEP forces. We followed the dielectrophoretic movement and deformation changes of 100 glioma cells at each frequency. We observed that the mean dielectrophoretic displacements of glioma cells were significantly different at varying frequencies with the maximum and minimum traveling distances of 13.22 µm and 1.37 µm, respectively. The dielectrophoretic deformation indexes of U87 glioma cells altered between 0.027-0.040. It was 0.036 in the absence of dielectrophoretic forces. This approach presents a rapid, robust, and sensitive characterization method for quantifying membrane deformation of glioma cells to determine the state of the cells or efficacy of administrated drugs.
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Affiliation(s)
- Meltem Elitas
- Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
| | - Monsur Islam
- Institute for Microstructure Technology, Karlsruhe Institute of Technology, 76344 Karlsruhe, Germany
| | - Jan G. Korvink
- Institute for Microstructure Technology, Karlsruhe Institute of Technology, 76344 Karlsruhe, Germany
| | - Esra Sengul
- Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
- Department of Physiology Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK
| | - Pouya Sharbati
- Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
| | - Beyzanur Ozogul
- Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
| | - Sumeyra Vural Kaymaz
- Faculty of Engineering and Natural Sciences, Sabanci University, Istanbul 34956, Turkey
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9
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Tan Y, Hu X, Hou Y, Chu Z. Emerging Diamond Quantum Sensing in Bio-Membranes. MEMBRANES 2022; 12:957. [PMID: 36295716 PMCID: PMC9609316 DOI: 10.3390/membranes12100957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/19/2022] [Accepted: 09/20/2022] [Indexed: 06/16/2023]
Abstract
Bio-membranes exhibit complex but unique mechanical properties as communicative regulators in various physiological and pathological processes. Exposed to a dynamic micro-environment, bio-membranes can be seen as an intricate and delicate system. The systematical modeling and detection of their local physical properties are often difficult to achieve, both quantitatively and precisely. The recent emerging diamonds hosting quantum defects (i.e., nitrogen-vacancy (NV) center) demonstrate intriguing optical and spin properties, together with their outstanding photostability and biocompatibility, rendering them ideal candidates for biological applications. Notably, the extraordinary spin-based sensing enable the measurements of localized nanoscale physical quantities such as magnetic fields, electrical fields, temperature, and strain. These nanoscale signals can be optically read out precisely by simple optical microscopy systems. Given these exclusive properties, NV-center-based quantum sensors can be widely applied in exploring bio-membrane-related features and the communicative chemical reaction processes. This review mainly focuses on NV-based quantum sensing in bio-membrane fields. The attempts of applying NV-based quantum sensors in bio-membranes to investigate diverse physical and chemical events such as membrane elasticity, phase change, nanoscale bio-physical signals, and free radical formation are fully overviewed. We also discuss the challenges and future directions of this novel technology to be utilized in bio-membranes.
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Affiliation(s)
- Yayin Tan
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong 999077, China
| | - Xinhao Hu
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong 999077, China
| | - Yong Hou
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong 999077, China
| | - Zhiqin Chu
- Department of Electrical and Electronic Engineering, The University of Hong Kong, Hong Kong 999077, China
- Joint Appointment with School of Biomedical Sciences, The University of Hong Kong, Hong Kong 999077, China
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10
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Toma HE, Oliveira D, Melo FMDE. Magnetic alignment of rhodamine/magnetite dual-labeled microtubules probed with inverted fluorescence microscopy. AN ACAD BRAS CIENC 2022; 94:e20210917. [PMID: 35920489 DOI: 10.1590/0001-3765202220210917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 10/17/2021] [Indexed: 11/22/2022] Open
Abstract
Molecular machines, as exemplified by the kinesin and microtubule system, are responsible for molecular transport in cells. The monitoring of the cellular machinery has attracted much attention in recent years, requiring sophisticated techniques such as optical tweezers, and dark field hyperspectral and fluorescence microscopies. It also demands suitable procedures for immobilization and labeling with functional agents such as dyes, plasmonic nanoparticles and quantum dots. In this work, microtubules were co-polymerized by incubating a tubulin mix consisting of 7 biotinylated tubulin to 3 rhodamine tubulin. Rhodamine provided the fluorescent tag, while biotin was the anchoring group for receiving streptavidin containing species. To control the microtubule alignment and consequently, the molecular gliding directions, functionalized iron oxide nanoparticles were employed in the presence of an external magnet field. Such iron oxide nanoparticles, (MagNPs) were previously coated with silica and (3-aminopro-pyl)triethoxysilane (APTS) and then modified with streptavidin (SA) for linking to the biotin-functionalized microtubules. In this way, the binding has been successfully performed, and the magnetic alignment probed by Inverted Fluorescence Microscopy. The proposed strategy has proved promising, as tested with one of the most important biological structures of the cellular machinery.
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Affiliation(s)
- Henrique Eisi Toma
- Universidade de São Paulo, Instituto de Química, Av. Prof. Lineu Prestes, 748, Cidade Universitária, 05508-000 São Paulo, SP, Brazil
| | - Daniel Oliveira
- Universidade de São Paulo, Instituto de Química, Av. Prof. Lineu Prestes, 748, Cidade Universitária, 05508-000 São Paulo, SP, Brazil
| | - Fernando M DE Melo
- Universidade de São Paulo, Instituto de Química, Av. Prof. Lineu Prestes, 748, Cidade Universitária, 05508-000 São Paulo, SP, Brazil
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11
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Català-Castro F, Schäffer E, Krieg M. Exploring cell and tissue mechanics with optical tweezers. J Cell Sci 2022; 135:jcs259355. [PMID: 35942913 DOI: 10.1242/jcs.259355] [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] [Indexed: 11/20/2022] Open
Abstract
Cellular and tissue biosystems emerge from the assembly of their constituent molecules and obtain a set of specific material properties. To measure these properties and understand how they influence cellular function is a central goal of mechanobiology. From a bottoms-up, physics or engineering point-of-view, such systems are a composition of basic mechanical elements. However, the sheer number and dynamic complexity of them, including active molecular machines and their emergent properties, makes it currently intractable to calculate how biosystems respond to forces. Because many diseases result from an aberrant mechanotransduction, it is thus essential to measure this response. Recent advances in the technology of optical tweezers have broadened their scope from single-molecule applications to measurements inside complex cellular environments, even within tissues and animals. Here, we summarize the basic optical trapping principles, implementations and calibration procedures that enable force measurements using optical tweezers directly inside cells of living animals, in combination with complementary techniques. We review their versatility to manipulate subcellular organelles and measure cellular frequency-dependent mechanics in the piconewton force range from microseconds to hours. As an outlook, we address future challenges to fully unlock the potential of optical tweezers for mechanobiology.
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Affiliation(s)
- Frederic Català-Castro
- Neurophotonics and Mechanical Systems Biology, ICFO, Institut de Ciències Fotòniques, 08860 Castelldefels, Spain
| | - Erik Schäffer
- Cellular Nanoscience, ZMBP, University of Tübingen, 72076 Tübingen, Germany
| | - Michael Krieg
- Neurophotonics and Mechanical Systems Biology, ICFO, Institut de Ciències Fotòniques, 08860 Castelldefels, Spain
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12
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Vibration, a treatment for migraine, linked to calpain driven changes in actin cytoskeleton. PLoS One 2022; 17:e0262058. [PMID: 35482731 PMCID: PMC9049534 DOI: 10.1371/journal.pone.0262058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 04/04/2022] [Indexed: 11/19/2022] Open
Abstract
Understanding how a human cell reacts to external physical stimuli is essential to understanding why vibration can elicit localized pain reduction. Stimulation of epithelial cells with external vibration forces has been shown to change cell shape, particularly in regards to structures involved in non-muscle cell motility. We hypothesized that epithelial cells respond to vibration transduction by altering proteins involved in remodeling cytoskeleton. Epithelial cells were exposed to vibration and assessed by microscopy, cytoskeletal staining, immunoblotting and quantitative RT-PCR. Here, we report that epithelial cell lines exposed to 15 minutes of vibration retract filopodia and concentrate actin at the periphery of the cell. In particular, we show an increased expression of the calcium-dependent, cysteine protease, calpain. The discovery that cell transitions are induced by limited exposure to natural forces, such as vibration, provides a foundation to explain how vibrational treatment helps migraine patients.
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13
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Kreysing E, Hugh JM, Foster SK, Andresen K, Greenhalgh RD, Pillai EK, Dimitracopoulos A, Keyser UF, Franze K. Effective cell membrane tension is independent of polyacrylamide substrate stiffness. PNAS NEXUS 2022; 2:pgac299. [PMID: 36733291 PMCID: PMC9887938 DOI: 10.1093/pnasnexus/pgac299] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 01/09/2023] [Indexed: 01/11/2023]
Abstract
Most animal cells are surrounded by a cell membrane and an underlying actomyosin cortex. Both structures are linked, and they are under tension. In-plane membrane tension and cortical tension both influence many cellular processes, including cell migration, division, and endocytosis. However, while actomyosin tension is regulated by substrate stiffness, how membrane tension responds to mechanical substrate properties is currently poorly understood. Here, we probed the effective membrane tension of neurons and fibroblasts cultured on glass and polyacrylamide substrates of varying stiffness using optical tweezers. In contrast to actomyosin-based traction forces, both peak forces and steady-state tether forces of cells cultured on hydrogels were independent of substrate stiffness and did not change after blocking myosin II activity using blebbistatin, indicating that tether and traction forces are not directly linked. Peak forces in fibroblasts on hydrogels were about twice as high as those in neurons, indicating stronger membrane-cortex adhesion in fibroblasts. Steady-state tether forces were generally higher in cells cultured on hydrogels than on glass, which we explain by a mechanical model. Our results provide new insights into the complex regulation of effective membrane tension and pave the way for a deeper understanding of the biological processes it instructs.
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Affiliation(s)
| | | | - Sarah K Foster
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK,Systems Biology of Microbial Communities, Cluster of Excellence—CMFI, University of Tübingen, 72076 Tübingen, Germany
| | - Kurt Andresen
- Department of Physics, Gettysburg College, Gettysburg, PA 17325, USA
| | - Ryan D Greenhalgh
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Eva K Pillai
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
| | - Andrea Dimitracopoulos
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
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14
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Vasan A, Orosco J, Magaram U, Duque M, Weiss C, Tufail Y, Chalasani SH, Friend J. Ultrasound Mediated Cellular Deflection Results in Cellular Depolarization. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2022; 9:e2101950. [PMID: 34747144 PMCID: PMC8805560 DOI: 10.1002/advs.202101950] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 09/16/2021] [Indexed: 05/29/2023]
Abstract
Ultrasound has been used to manipulate cells in both humans and animal models. While intramembrane cavitation and lipid clustering have been suggested as likely mechanisms, they lack experimental evidence. Here, high-speed digital holographic microscopy (kiloHertz order) is used to visualize the cellular membrane dynamics. It is shown that neuronal and fibroblast membranes deflect about 150 nm upon ultrasound stimulation. Next, a biomechanical model that predicts changes in membrane voltage after ultrasound exposure is developed. Finally, the model predictions are validated using whole-cell patch clamp electrophysiology on primary neurons. Collectively, it is shown that ultrasound stimulation directly defects the neuronal membrane leading to a change in membrane voltage and subsequent depolarization. The model is consistent with existing data and provides a mechanism for both ultrasound-evoked neurostimulation and sonogenetic control.
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Affiliation(s)
- Aditya Vasan
- Medically Advanced Devices LaboratoryDepartment of Mechanical and Aerospace EngineeringJacobs School of Engineering and Department of SurgerySchool of MedicineUniversity of California San DiegoLa JollaCA92093USA
| | - Jeremy Orosco
- Medically Advanced Devices LaboratoryDepartment of Mechanical and Aerospace EngineeringJacobs School of Engineering and Department of SurgerySchool of MedicineUniversity of California San DiegoLa JollaCA92093USA
| | - Uri Magaram
- Molecular Neurobiology LaboratoryThe Salk Institute for Biological StudiesLa JollaCA92037USA
| | - Marc Duque
- Molecular Neurobiology LaboratoryThe Salk Institute for Biological StudiesLa JollaCA92037USA
| | - Connor Weiss
- Molecular Neurobiology LaboratoryThe Salk Institute for Biological StudiesLa JollaCA92037USA
| | - Yusuf Tufail
- Molecular Neurobiology LaboratoryThe Salk Institute for Biological StudiesLa JollaCA92037USA
| | - Sreekanth H Chalasani
- Molecular Neurobiology LaboratoryThe Salk Institute for Biological StudiesLa JollaCA92037USA
| | - James Friend
- Medically Advanced Devices LaboratoryDepartment of Mechanical and Aerospace EngineeringJacobs School of Engineering and Department of SurgerySchool of MedicineUniversity of California San DiegoLa JollaCA92093USA
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15
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Lachaize V, Peña B, Ciubotaru C, Cojoc D, Chen SN, Taylor MRG, Mestroni L, Sbaizero O. Compromised Biomechanical Properties, Cell-Cell Adhesion and Nanotubes Communication in Cardiac Fibroblasts Carrying the Lamin A/C D192G Mutation. Int J Mol Sci 2021; 22:9193. [PMID: 34502098 PMCID: PMC8431729 DOI: 10.3390/ijms22179193] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/03/2021] [Accepted: 08/05/2021] [Indexed: 11/16/2022] Open
Abstract
Clinical effects induced by arrhythmogenic cardiomyopathy (ACM) originate from a large spectrum of genetic variations, including the missense mutation of the lamin A/C gene (LMNA), LMNA D192G. The aim of our study was to investigate the biophysical and biomechanical impact of the LMNA D192G mutation on neonatal rat ventricular fibroblasts (NRVF). The main findings in mutated NRVFs were: (i) cytoskeleton disorganization (actin and intermediate filaments); (ii) decreased elasticity of NRVFs; (iii) altered cell-cell adhesion properties, that highlighted a strong effect on cellular communication, in particular on tunneling nanotubes (TNTs). In mutant-expressing fibroblasts, these nanotubes were weakened with altered mechanical properties as shown by atomic force microscopy (AFM) and optical tweezers. These outcomes complement prior investigations on LMNA mutant cardiomyocytes and suggest that the LMNA D192G mutation impacts the biomechanical properties of both cardiomyocytes and cardiac fibroblasts. These observations could explain how this mutation influences cardiac biomechanical pathology and the severity of ACM in LMNA-cardiomyopathy.
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Affiliation(s)
- Veronique Lachaize
- Department of Engineering and Architecture, University of Trieste, Via Valerio 10, 34127 Trieste, Italy;
| | - Brisa Peña
- CU-Cardiovascular Institute, University of Colorado Anschutz Medical Campus, 12700 E. 19th Ave., Aurora, CO 80045, USA; (B.P.); (S.N.C.); (M.R.G.T.); (L.M.)
- Consortium for Fibrosis Research & Translation, Anschutz Medical Campus, University of Colorado, 12700 E. 19th Ave., Aurora, CO 80045, USA
- Bioengineering Department, University of Colorado Denver Anschutz Medical Campus, Bioscience 2 1270 E. Montview Ave., Suite 100, Aurora, CO 80045, USA
| | - Catalin Ciubotaru
- Institute of Materials, National Research Council of Italy (CNR_IOM), Area Science Park Basovizza, 34149 Trieste, Italy; (C.C.); (D.C.)
| | - Dan Cojoc
- Institute of Materials, National Research Council of Italy (CNR_IOM), Area Science Park Basovizza, 34149 Trieste, Italy; (C.C.); (D.C.)
| | - Suet Nee Chen
- CU-Cardiovascular Institute, University of Colorado Anschutz Medical Campus, 12700 E. 19th Ave., Aurora, CO 80045, USA; (B.P.); (S.N.C.); (M.R.G.T.); (L.M.)
| | - Matthew R. G. Taylor
- CU-Cardiovascular Institute, University of Colorado Anschutz Medical Campus, 12700 E. 19th Ave., Aurora, CO 80045, USA; (B.P.); (S.N.C.); (M.R.G.T.); (L.M.)
| | - Luisa Mestroni
- CU-Cardiovascular Institute, University of Colorado Anschutz Medical Campus, 12700 E. 19th Ave., Aurora, CO 80045, USA; (B.P.); (S.N.C.); (M.R.G.T.); (L.M.)
| | - Orfeo Sbaizero
- Department of Engineering and Architecture, University of Trieste, Via Valerio 10, 34127 Trieste, Italy;
- CU-Cardiovascular Institute, University of Colorado Anschutz Medical Campus, 12700 E. 19th Ave., Aurora, CO 80045, USA; (B.P.); (S.N.C.); (M.R.G.T.); (L.M.)
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16
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Corsetti S, Dholakia K. Optical manipulation: advances for biophotonics in the 21st century. JOURNAL OF BIOMEDICAL OPTICS 2021; 26:JBO-210127-PER. [PMID: 34235899 PMCID: PMC8262092 DOI: 10.1117/1.jbo.26.7.070602] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 06/17/2021] [Indexed: 05/10/2023]
Abstract
SIGNIFICANCE Optical trapping is a technique capable of applying minute forces that has been applied to studies spanning single molecules up to microorganisms. AIM The goal of this perspective is to highlight some of the main advances in the last decade in this field that are pertinent for a biomedical audience. APPROACH First, the direct determination of forces in optical tweezers and the combination of optical and acoustic traps, which allows studies across different length scales, are discussed. Then, a review of the progress made in the direct trapping of both single-molecules, and even single-viruses, and single cells with optical forces is outlined. Lastly, future directions for this methodology in biophotonics are discussed. RESULTS In the 21st century, optical manipulation has expanded its unique capabilities, enabling not only a more detailed study of single molecules and single cells but also of more complex living systems, giving us further insights into important biological activities. CONCLUSIONS Optical forces have played a large role in the biomedical landscape leading to exceptional new biological breakthroughs. The continuous advances in the world of optical trapping will certainly lead to further exploitation, including exciting in-vivo experiments.
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Affiliation(s)
- Stella Corsetti
- University of St Andrews, SUPA, School of Physics and Astronomy, St. Andrews, United Kingdom
- Address all correspondence to Stella Corsetti,
| | - Kishan Dholakia
- University of St Andrews, SUPA, School of Physics and Astronomy, St. Andrews, United Kingdom
- University of Adelaide, School of Biological Sciences, Adelaide, South Australia, Australia
- Yonsei University, College of Science, Department of Physics, Seoul, Republic of Korea
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17
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Biomechanics of Neutrophil Tethers. Life (Basel) 2021; 11:life11060515. [PMID: 34073130 PMCID: PMC8230032 DOI: 10.3390/life11060515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Revised: 05/22/2021] [Accepted: 05/25/2021] [Indexed: 12/11/2022] Open
Abstract
Leukocytes, including neutrophils, propelled by blood flow, can roll on inflamed endothelium using transient bonds between selectins and their ligands, and integrins and their ligands. When such receptor–ligand bonds last long enough, the leukocyte microvilli become extended and eventually form thin, 20 µm long tethers. Tether formation can be observed in blood vessels in vivo and in microfluidic flow chambers. Tethers can also be extracted using micropipette aspiration, biomembrane force probe, optical trap, or atomic force microscopy approaches. Here, we review the biomechanical properties of leukocyte tethers as gleaned from such measurements and discuss the advantages and disadvantages of each approach. We also review and discuss viscoelastic models that describe the dependence of tether formation on time, force, rate of loading, and cell activation. We close by emphasizing the need to combine experimental observations with quantitative models and computer simulations to understand how tether formation is affected by membrane tension, membrane reservoir, and interactions of the membrane with the cytoskeleton.
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18
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Adamczyk O, Baster Z, Szczypior M, Rajfur Z. Substrate Stiffness Mediates Formation of Novel Cytoskeletal Structures in Fibroblasts during Cell-Microspheres Interaction. Int J Mol Sci 2021; 22:960. [PMID: 33478069 PMCID: PMC7835802 DOI: 10.3390/ijms22020960] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/13/2021] [Accepted: 01/15/2021] [Indexed: 11/16/2022] Open
Abstract
It is well known that living cells interact mechanically with their microenvironment. Many basic cell functions, like migration, proliferation, gene expression, and differentiation, are influenced by external forces exerted on the cell. That is why it is extremely important to study how mechanical properties of the culture substrate influence the cellular molecular regulatory pathways. Optical microscopy is one of the most common experimental method used to visualize and study cellular processes. Confocal microscopy allows to observe changes in the 3D organization of the cytoskeleton in response to a precise mechanical stimulus applied with, for example, a bead trapped with optical tweezers. Optical tweezers-based method (OT) is a microrheological technique which employs a focused laser beam and polystyrene or latex beads to study mechanical properties of biological systems. Latex beads, functionalized with a specific protein, can interact with proteins located on the surface of the cellular membrane. Such interaction can significantly affect the cell's behavior. In this work, we demonstrate that beads alone, placed on the cell surface, significantly change the architecture of actin, microtubule, and intermediate filaments. We also show that the observed molecular response to such stimulus depends on the duration of the cell-bead interaction. Application of cytoskeletal drugs: cytochalasin D, jasplakinolide, and docetaxel, abrogates remodeling effects of the cytoskeleton. More important, when cells are plated on elastic substrates, which mimic the mechanical properties of physiological cellular environment, we observe formation of novel, "cup-like" structures formed by the microtubule cytoskeleton upon interaction with latex beads. These results provide new insights into the function of the microtubule cytoskeleton. Based on these results, we conclude that rigidity of the substrate significantly affects the cellular processes related to every component of the cytoskeleton, especially their architecture.
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Affiliation(s)
- Olga Adamczyk
- Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Kraków, Poland; (O.A.); (Z.B.); (M.S.)
| | - Zbigniew Baster
- Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Kraków, Poland; (O.A.); (Z.B.); (M.S.)
| | - Maksymilian Szczypior
- Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Kraków, Poland; (O.A.); (Z.B.); (M.S.)
| | - Zenon Rajfur
- Institute of Physics, Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, 30-348 Kraków, Poland; (O.A.); (Z.B.); (M.S.)
- Jagiellonian Center of Biomedical Imaging, Jagiellonian University, 30-348 Kraków, Poland
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19
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Romanov V, Silvani G, Zhu H, Cox CD, Martinac B. An Acoustic Platform for Single-Cell, High-Throughput Measurements of the Viscoelastic Properties of Cells. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2005759. [PMID: 33326190 DOI: 10.1002/smll.202005759] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 12/01/2020] [Indexed: 06/12/2023]
Abstract
Cellular processes including adhesion, migration, and differentiation are governed by the distinct mechanical properties of each cell. Importantly, the mechanical properties of individual cells can vary depending on local physical and biochemical cues in a time-dependent manner resulting in significant inter-cell heterogeneity. While several different methods have been developed to interrogate the mechanical properties of single cells, throughput to capture this heterogeneity remains an issue. Here, single-cell, high-throughput characterization of adherent cells is demonstrated using acoustic force spectroscopy (AFS). AFS works by simultaneously, acoustically driving tens to hundreds of silica beads attached to cells away from the cell surface, allowing the user to measure the stiffness of adherent cells under multiple experimental conditions. It is shown that cells undergo marked changes in viscoelasticity as a function of temperature, by altering the temperature within the AFS microfluidic circuit between 21 and 37 °C. In addition, quantitative differences in cells exposed to different pharmacological treatments specifically targeting the membrane-cytoskeleton interface are shown. Further, the high-throughput format of the AFS is utilized to rapidly probe, in excess of 1000 cells, three different cell lines expressing different levels of a mechanosensitive protein, Piezo1, demonstrating the ability to differentiate between cells based on protein expression levels.
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Affiliation(s)
- Valentin Romanov
- Department of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Giulia Silvani
- Department of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, Darlinghurst, Sydney, NSW, 2010, Australia
| | - Huiyu Zhu
- Faculty of Science, University of Technology Sydney, Ultimo, Sydney, NSW, 2007, Australia
| | - Charles D Cox
- Department of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, Darlinghurst, Sydney, NSW, 2010, Australia
- St Vincent's Clinical School, University of New South Wales, Sydney, NSW, 2010, Australia
| | - Boris Martinac
- Department of Molecular Cardiology and Biophysics, Victor Chang Cardiac Research Institute, Darlinghurst, Sydney, NSW, 2010, Australia
- St Vincent's Clinical School, University of New South Wales, Sydney, NSW, 2010, Australia
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20
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Lenton ICD, Scott EK, Rubinsztein-Dunlop H, Favre-Bulle IA. Optical Tweezers Exploring Neuroscience. Front Bioeng Biotechnol 2020; 8:602797. [PMID: 33330435 PMCID: PMC7732537 DOI: 10.3389/fbioe.2020.602797] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 11/04/2020] [Indexed: 12/30/2022] Open
Abstract
Over the past decade, optical tweezers (OT) have been increasingly used in neuroscience for studies of molecules and neuronal dynamics, as well as for the study of model organisms as a whole. Compared to other areas of biology, it has taken much longer for OT to become an established tool in neuroscience. This is, in part, due to the complexity of the brain and the inherent difficulties in trapping individual molecules or manipulating cells located deep within biological tissue. Recent advances in OT, as well as parallel developments in imaging and adaptive optics, have significantly extended the capabilities of OT. In this review, we describe how OT became an established tool in neuroscience and we elaborate on possible future directions for the field. Rather than covering all applications of OT to neurons or related proteins and molecules, we focus our discussions on studies that provide crucial information to neuroscience, such as neuron dynamics, growth, and communication, as these studies have revealed meaningful information and provide direction for the field into the future.
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Affiliation(s)
- Isaac C. D. Lenton
- School of Mathematics and Physics, The University of Queensland, Brisbane, QLD, Australia
| | - Ethan K. Scott
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
| | | | - Itia A. Favre-Bulle
- School of Mathematics and Physics, The University of Queensland, Brisbane, QLD, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, Australia
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21
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Membrane interactions in drug delivery: Model cell membranes and orthogonal techniques. Adv Colloid Interface Sci 2020; 281:102177. [PMID: 32417568 DOI: 10.1016/j.cis.2020.102177] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 03/05/2020] [Accepted: 05/07/2020] [Indexed: 01/22/2023]
Abstract
To generate the desired effect in the human body, the active pharmaceutical ingredient usually needs to interact with a receptor located on the cell membrane or inside the cell. Thus, understanding membrane interactions is of great importance when it comes to the development and testing of new drug molecules or new drug delivery systems. Nowadays, there is a tremendous selection of both model cell membranes and of techniques that can be used to characterize interactions between selected model cell membranes and a drug molecule, an excipient, or a drug delivery system. Having such a wide selection of model cell membranes and techniques available makes it sometimes challenging to select the optimal combination for a specific study. Furthermore, it is difficult to compare results obtained using different model cell membranes and techniques, and not all in vitro studies translate as well to an estimation of the in vivo biological activity or understanding of mode of action. This review provides an overview of the available lipid bilayer-based model cell membranes and of the most widely employed techniques for studying membrane interactions. Finally, the need for employing complimentary characterization techniques in order to acquire more reliable and in-depth information is highlighted.
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22
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Melo B, Almeida F, Temporão G, Guerreiro T. Relaxing constraints on data acquisition and position detection for trap stiffness calibration in optical tweezers. OPTICS EXPRESS 2020; 28:16256-16269. [PMID: 32549451 DOI: 10.1364/oe.394632] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 05/01/2020] [Indexed: 06/11/2023]
Abstract
Optical tweezers find applications in various fields, ranging from biology to physics. One of the fundamental steps necessary to perform quantitative measurements using trapped particles is the calibration of the tweezer's spring constant. This can be done through power spectral density analysis, from forward scattering detection of the particle's position. In this work we propose and experimentally test simplifications to such measurement procedure, aimed at reducing post-processing of recorded data and dealing with acquisition devices that have frequency-dependent electronic noise. In the same line of simplifying the tweezer setup we also present a knife-edge detection scheme that can substitute standard position sensitive detectors.
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23
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Zhu R, Avsievich T, Popov A, Meglinski I. Optical Tweezers in Studies of Red Blood Cells. Cells 2020; 9:E545. [PMID: 32111018 PMCID: PMC7140472 DOI: 10.3390/cells9030545] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/05/2020] [Accepted: 02/11/2020] [Indexed: 12/11/2022] Open
Abstract
Optical tweezers (OTs) are innovative instruments utilized for the manipulation of microscopic biological objects of interest. Rapid improvements in precision and degree of freedom of multichannel and multifunctional OTs have ushered in a new era of studies in basic physical and chemical properties of living tissues and unknown biomechanics in biological processes. Nowadays, OTs are used extensively for studying living cells and have initiated far-reaching influence in various fundamental studies in life sciences. There is also a high potential for using OTs in haemorheology, investigations of blood microcirculation and the mutual interplay of blood cells. In fact, in spite of their great promise in the application of OTs-based approaches for the study of blood, cell formation and maturation in erythropoiesis have not been fully explored. In this review, the background of OTs, their state-of-the-art applications in exploring single-cell level characteristics and bio-rheological properties of mature red blood cells (RBCs) as well as the OTs-assisted studies on erythropoiesis are summarized and presented. The advance developments and future perspectives of the OTs' application in haemorheology both for fundamental and practical in-depth studies of RBCs formation, functional diagnostics and therapeutic needs are highlighted.
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Affiliation(s)
- Ruixue Zhu
- Optoelectronics and Measurement Techniques Laboratory, University of Oulu, 90570 Oulu, Finland; (T.A.); (A.P.)
| | - Tatiana Avsievich
- Optoelectronics and Measurement Techniques Laboratory, University of Oulu, 90570 Oulu, Finland; (T.A.); (A.P.)
| | - Alexey Popov
- Optoelectronics and Measurement Techniques Laboratory, University of Oulu, 90570 Oulu, Finland; (T.A.); (A.P.)
| | - Igor Meglinski
- Optoelectronics and Measurement Techniques Laboratory, University of Oulu, 90570 Oulu, Finland; (T.A.); (A.P.)
- Interdisciplinary Laboratory of Biophotonics, National Research Tomsk State University, 634050 Tomsk, Russia
- Institute of Engineering Physics for Biomedicine (PhysBio), National Research Nuclear University (MEPhI), 115409 Moscow, Russia
- Aston Institute of Materials Research, School of Engineering and Applied Science, Aston University, Birmingham B4 7ET, UK
- School of Life and Health Sciences, Aston University, Birmingham B4 7ET, UK
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24
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From Far-Field to Near-Field Micro- and Nanoparticle Optical Trapping. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app10041375] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Optical tweezers are a very well-established technique that have developed into a standard tool for trapping and manipulating micron and submicron particles with great success in the last decades. Although the nature of light enforces restrictions on the minimum particle size that can be efficiently trapped due to Abbe’s diffraction limit, scientists have managed to overcome this problem by engineering new devices that exploit near-field effects. Nowadays, metallic nanostructures can be fabricated which, under laser illumination, produce a secondary plasmonic field that does not suffer from the diffraction limit. This advance offers a great improvement in nanoparticle trapping, as it relaxes the trapping requirements compared to conventional optical tweezers although problems may arise due to thermal heating of the metallic nanostructures. This could hinder efficient trapping and damage the trapped object. In this work, we review the fundamentals of conventional optical tweezers, the so-called plasmonic tweezers, and related phenomena. Starting from the conception of the idea by Arthur Ashkin until recent improvements and applications, we present the principles of these techniques along with their limitations. Emphasis in this review is on the successive improvements of the techniques and the innovative aspects that have been devised to overcome some of the main challenges.
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25
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De Martino S, Zhang W, Klausen L, Lou HY, Li X, Alfonso FS, Cavalli S, Netti PA, Santoro F, Cui B. Dynamic Manipulation of Cell Membrane Curvature by Light-Driven Reshaping of Azopolymer. NANO LETTERS 2020; 20:577-584. [PMID: 31846332 PMCID: PMC7207080 DOI: 10.1021/acs.nanolett.9b04307] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Local curvatures on the cell membrane serve as signaling hubs that promote curvature-dependent protein interactions and modulate a variety of cellular processes including endocytosis, exocytosis, and the actin cytoskeleton. However, precisely controlling the location and the degree of membrane curvature in live cells has not been possible until recently, where studies show that nanofabricated vertical structures on a substrate can imprint their shapes on the cell membrane to induce well-defined curvatures in adherent cells. Nevertheless, the intrinsic static nature of these engineered nanostructures prevents dynamic modulation of membrane curvatures. In this work, we engineer light-responsive polymer structures whose shape can be dynamically modulated by light and thus change the induced-membrane curvatures on-demand. Specifically, we fabricate three-dimensional azobenzene-based polymer structures that change from a vertical pillar to an elongated vertical bar shape upon green light illumination. We observe that U2OS cells cultured on azopolymer nanostructures rapidly respond to the topographical change of the substrate underneath. The dynamically induced high membrane curvatures at bar ends promote local accumulation of actin fibers and actin nucleator Arp2/3 complex. The ability to dynamically manipulate the membrane curvature and analyze protein response in real-time provides a new way to study curvature-dependent processes in live cells.
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Affiliation(s)
- Selene De Martino
- Center for Advanced Biomaterials for Healthcare, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci, 53, 80125 Napoli, Italy
- Dipartimento di Ingegneria Chimica dei Materiali e della Produzione Industriale, DICMAPI, Università degli Studi di Napoli Federico II, Piazzale Tecchio, 80, 80125 Napoli, Italy
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, United States
| | - Wei Zhang
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, United States
| | - Lasse Klausen
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, United States
| | - Hsin-Ya Lou
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, United States
| | - Xiao Li
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, United States
| | - Felix S. Alfonso
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, United States
| | - Silvia Cavalli
- Center for Advanced Biomaterials for Healthcare, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci, 53, 80125 Napoli, Italy
| | - Paolo A. Netti
- Center for Advanced Biomaterials for Healthcare, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci, 53, 80125 Napoli, Italy
- Dipartimento di Ingegneria Chimica dei Materiali e della Produzione Industriale, DICMAPI, Università degli Studi di Napoli Federico II, Piazzale Tecchio, 80, 80125 Napoli, Italy
| | - Francesca Santoro
- Center for Advanced Biomaterials for Healthcare, Istituto Italiano di Tecnologia, Largo Barsanti e Matteucci, 53, 80125 Napoli, Italy
- Corresponding Authors:.
| | - Bianxiao Cui
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, California 94305, United States
- Corresponding Authors:.
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26
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Piontek MC, Lira RB, Roos WH. Active probing of the mechanical properties of biological and synthetic vesicles. Biochim Biophys Acta Gen Subj 2019; 1865:129486. [PMID: 31734458 DOI: 10.1016/j.bbagen.2019.129486] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 11/05/2019] [Accepted: 11/09/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND The interest in mechanics of synthetic and biological vesicles has been continuously growing during the last decades. Liposomes serve as model systems for investigating fundamental membrane processes and properties. More recently, extracellular vesicles (EVs) have been investigated mechanically as well. EVs are widely studied in fundamental and applied sciences, but their material properties remained elusive until recently. Elucidating the mechanical properties of vesicles is essential to unveil the mechanisms behind a variety of biological processes, e.g. budding, vesiculation and cellular uptake mechanisms. SCOPE OF REVIEW The importance of mechanobiology for studies of vesicles and membranes is discussed, as well as the different available techniques to probe their mechanical properties. In particular, the mechanics of vesicles and membranes as obtained by nanoindentation, micropipette aspiration, optical tweezers, electrodeformation and electroporation experiments is addressed. MAJOR CONCLUSIONS EVs and liposomes possess an astonishing rich, diverse behavior. To better understand their properties, and for optimization of their applications in nanotechnology, an improved understanding of their mechanical properties is needed. Depending on the size of the vesicles and the specific scientific question, different techniques can be chosen for their mechanical characterization. GENERAL SIGNIFICANCE Understanding the mechanical properties of vesicles is necessary to gain deeper insight in the fundamental biological mechanisms involved in vesicle generation and cellular uptake. This furthermore facilitates technological applications such as using vesicles as targeted drug delivery vehicles. Liposome studies provide insight into fundamental membrane processes and properties, whereas the role and functioning of EVs in biology and medicine are increasingly elucidated.
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Affiliation(s)
- Melissa C Piontek
- Moleculaire Biofysica, Zernike Instituut, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands.
| | - Rafael B Lira
- Moleculaire Biofysica, Zernike Instituut, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands.
| | - Wouter H Roos
- Moleculaire Biofysica, Zernike Instituut, Rijksuniversiteit Groningen, Nijenborgh 4, 9747 AG Groningen, the Netherlands.
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27
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Arbore C, Perego L, Sergides M, Capitanio M. Probing force in living cells with optical tweezers: from single-molecule mechanics to cell mechanotransduction. Biophys Rev 2019; 11:765-782. [PMID: 31612379 PMCID: PMC6815294 DOI: 10.1007/s12551-019-00599-y] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 09/05/2019] [Indexed: 01/12/2023] Open
Abstract
The invention of optical tweezers more than three decades ago has opened new avenues in the study of the mechanical properties of biological molecules and cells. Quantitative force measurements still represent a challenging task in living cells due to the complexity of the cellular environment. Here, we review different methodologies to quantitatively measure the mechanical properties of living cells, the strength of adhesion/receptor bonds, and the active force produced during intracellular transport, cell adhesion, and migration. We discuss experimental strategies to attain proper calibration of optical tweezers and molecular resolution in living cells. Finally, we show recent studies on the transduction of mechanical stimuli into biomolecular and genetic signals that play a critical role in cell health and disease.
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Affiliation(s)
- Claudia Arbore
- LENS - European Laboratory for Non-linear Spectroscopy, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - Laura Perego
- LENS - European Laboratory for Non-linear Spectroscopy, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - Marios Sergides
- LENS - European Laboratory for Non-linear Spectroscopy, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy
| | - Marco Capitanio
- LENS - European Laboratory for Non-linear Spectroscopy, Via Nello Carrara 1, 50019, Sesto Fiorentino, Italy.
- Department of Physics and Astronomy, University of Florence, Via Sansone 1, 50019, Sesto Fiorentino, Italy.
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Charlton SGV, White MA, Jana S, Eland LE, Jayathilake PG, Burgess JG, Chen J, Wipat A, Curtis TP. Regulating, Measuring, and Modeling the Viscoelasticity of Bacterial Biofilms. J Bacteriol 2019; 201:e00101-19. [PMID: 31182499 PMCID: PMC6707926 DOI: 10.1128/jb.00101-19] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Biofilms occur in a broad range of environments under heterogeneous physicochemical conditions, such as in bioremediation plants, on surfaces of biomedical implants, and in the lungs of cystic fibrosis patients. In these scenarios, biofilms are subjected to shear forces, but the mechanical integrity of these aggregates often prevents their disruption or dispersal. Biofilms' physical robustness is the result of the multiple biopolymers secreted by constituent microbial cells which are also responsible for numerous biological functions. A better understanding of the role of these biopolymers and their response to dynamic forces is therefore crucial for understanding the interplay between biofilm structure and function. In this paper, we review experimental techniques in rheology, which help quantify the viscoelasticity of biofilms, and modeling approaches from soft matter physics that can assist our understanding of the rheological properties. We describe how these methods could be combined with synthetic biology approaches to control and investigate the effects of secreted polymers on the physical properties of biofilms. We argue that without an integrated approach of the three disciplines, the links between genetics, composition, and interaction of matrix biopolymers and the viscoelastic properties of biofilms will be much harder to uncover.
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Affiliation(s)
- Samuel G V Charlton
- School of Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Michael A White
- Interdisciplinary Computing & Complex BioSystems Research Group, School of Computing, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Saikat Jana
- School of Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Lucy E Eland
- Interdisciplinary Computing & Complex BioSystems Research Group, School of Computing, Newcastle University, Newcastle upon Tyne, United Kingdom
| | | | - J Grant Burgess
- School of Natural & Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Jinju Chen
- School of Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Anil Wipat
- Interdisciplinary Computing & Complex BioSystems Research Group, School of Computing, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Thomas P Curtis
- School of Engineering, Newcastle University, Newcastle upon Tyne, United Kingdom
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29
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Araújo GRDS, Viana NB, Gómez F, Pontes B, Frases S. The mechanical properties of microbial surfaces and biofilms. ACTA ACUST UNITED AC 2019; 5:100028. [PMID: 32743144 PMCID: PMC7389442 DOI: 10.1016/j.tcsw.2019.100028] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 07/23/2019] [Indexed: 12/13/2022]
Abstract
Microbes can modify their surface structure as an adaptive mechanism for survival and dissemination in the environment or inside the host. Altering their ability to respond to mechanical stimuli is part of this adaptive process. Since the 1990s, powerful micromanipulation tools have been developed that allow mechanical studies of microbial cell surfaces, exploring little known aspects of their dynamic behavior. This review concentrates on the study of mechanical and rheological properties of bacteria and fungi, focusing on their cell surface dynamics and biofilm formation.
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Affiliation(s)
- Glauber R de S Araújo
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Nathan B Viana
- Laboratório de Pinças Óticas (LPO-COPEA), Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.,Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.,Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Fran Gómez
- Laboratório de Pinças Óticas (LPO-COPEA), Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.,Instituto de Física, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Bruno Pontes
- Laboratório de Pinças Óticas (LPO-COPEA), Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.,Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Susana Frases
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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30
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Nussenzveig HM. Are cell membrane nanotubes the ancestors of the nervous system? EUROPEAN BIOPHYSICS JOURNAL: EBJ 2019; 48:593-598. [DOI: 10.1007/s00249-019-01388-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 05/27/2019] [Accepted: 07/01/2019] [Indexed: 01/21/2023]
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31
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Oliveira L, Campos WH, Rocha MS. Optical Trapping and Manipulation of Superparamagnetic Beads Using Annular-Shaped Beams. Methods Protoc 2018. [PMCID: PMC6481052 DOI: 10.3390/mps1040044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We propose an optical tweezers setup based on an annular-shaped laser beam that is efficient to trap 2.8 μm-diameter superparamagnetic particles. The optical trapping of such particles was fully characterized, and a direct absolute comparison with a geometrical optics model was performed. With this comparison, we were able to show that light absorption by the superparamagnetic particles is negligible for our annular beam tweezers, differing from the case of conventional Gaussian beam tweezers, in which laser absorption by the beads makes stable trapping difficult. In addition, the trap stiffness of the annular beam tweezers increases with the laser power and with the bead distance from the coverslip surface. While this first result is expected and similar to that achieved for conventional Gaussian tweezers, which use ordinary dielectric beads, the second result is quite surprising and different from the ordinary case, suggesting that spherical aberration is much less important in our annular beam geometry. The results obtained here provide new insights into the development of hybrid optomagnetic tweezers, which can apply simultaneously optical and magnetic forces on the same particles.
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32
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Lemma ED, Spagnolo B, De Vittorio M, Pisanello F. Studying Cell Mechanobiology in 3D: The Two-Photon Lithography Approach. Trends Biotechnol 2018; 37:358-372. [PMID: 30343948 DOI: 10.1016/j.tibtech.2018.09.008] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 09/19/2018] [Accepted: 09/19/2018] [Indexed: 12/12/2022]
Abstract
Two-photon lithography is a laser writing technique that can produce 3D microstructures with resolutions below the diffraction limit. This review focuses on its applications to study mechanical properties of cells, an emerging field known as mechanobiology. We review 3D structural designs and materials in the context of new experimental designs, including estimating forces exerted by single cells, studying selective adhesion on substrates, and creating 3D networks of cells. We then focus on emerging applications, including structures for assessing cancer cell invasiveness, whose migration properties depend on the cell mechanical response to the environment, and 3D architectures and materials to study stem cell differentiation, as 3D structure shape and patterning play a key role in defining cell fates.
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Affiliation(s)
- Enrico Domenico Lemma
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Via Barsanti snc, 73010 Arnesano, Italy; Università del Salento, Dipartimento di Ingegneria dell'Innovazione, via per Monteroni snc, 73100 Lecce, Italy; Current address: Karlsruher Institut für Technologie, Zoologisches Institut, Zell- und Neurobiologie, Fritz-Haber-Weg 4, 76131 Karlsruhe, Germany.
| | - Barbara Spagnolo
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Via Barsanti snc, 73010 Arnesano, Italy
| | - Massimo De Vittorio
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Via Barsanti snc, 73010 Arnesano, Italy; Università del Salento, Dipartimento di Ingegneria dell'Innovazione, via per Monteroni snc, 73100 Lecce, Italy; These authors equally contributed to this work
| | - Ferruccio Pisanello
- Istituto Italiano di Tecnologia, Center for Biomolecular Nanotechnologies, Via Barsanti snc, 73010 Arnesano, Italy; These authors equally contributed to this work.
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Campos WH, Fonseca JM, Mendes JBS, Rocha MS, Moura-Melo WA. How light absorption modifies the radiative force on a microparticle in optical tweezers. APPLIED OPTICS 2018; 57:7216-7224. [PMID: 30182982 DOI: 10.1364/ao.57.007216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Accepted: 08/01/2018] [Indexed: 06/08/2023]
Abstract
Reflection and refraction of light can be used to trap small dielectric particles in the geometrical optics regime. Absorption of light is usually neglected in theoretical calculations, but it is known that it occurs in the optical trapping of semi-transparent particles. Here, we propose a generalization of Ashkin's model for the radiative force exerted on a spherical bead, including the contribution due to attenuation/absorption of light in the bulk of the particle. We discuss in detail the balance between refraction, reflection, and absorption for different optical parameters and particle sizes. Our findings contribute to the understanding of optical trapping of light-absorbing particles and may be used to predict whenever absorption is important in real experiments.
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