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Zao YJ, Cheng G, Feng MM, Wang YX, Zhang ZF, Zhang X, Jiang P. Trichinella spiralis cathepsin B bound and degraded host's intestinal type I collagen. Int J Biol Macromol 2024; 257:128728. [PMID: 38092101 DOI: 10.1016/j.ijbiomac.2023.128728] [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: 06/08/2023] [Revised: 11/12/2023] [Accepted: 12/08/2023] [Indexed: 12/20/2023]
Abstract
Trichinellosis is a zoonotic parasitic disease that poses threats to human health, the meat industry, food safety, and huge financial losses. The critical stage of Trichinella spiralis (T. spiralis) infection is the invasion of intestinal larvae into the host's intestinal epithelial cells (IECs). T. spiralis Cathepsin B (TsCB) specifically interacts with IECs to facilitate the invasion of larvae. This study aims to look at how TsCB affects mouse IECs. TsCB was successfully cloned, expressed, and characterized, demonstrating its natural cysteine protease hydrolysis activity. A total of 140 proteins that interact with rTsCB were identified by GST pull-down combined with LC-MS/MS, including type I collagen, an essential component of the host's intestinal epithelial barrier system and intimately related to intestinal epithelial damage. TsCB transcription and expression levels rise, whereas type I collagen in the host's intestinal mucosa declines when the T. spiralis larvae invaded. Besides, it was discovered that TsCB bound to and degraded type I collagen of the host's intestine. This research can serve as a foundation for clarifying how T. spiralis invades the host's intestinal barrier and might provide information on potential targets for the creation of novel treatments to treat parasite illnesses.
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Affiliation(s)
- You Jiao Zao
- Department of Pathogen Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, PR China; Yunan University School of Medicine, Kunming 650091, PR China
| | - Ge Cheng
- Department of Pathogen Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, PR China
| | - Miao Miao Feng
- Department of Pathogen Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, PR China
| | - Yi Xuan Wang
- Department of Pathogen Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, PR China
| | - Zi Fang Zhang
- Department of Pathogen Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, PR China
| | - Xi Zhang
- Department of Pathogen Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, PR China
| | - Peng Jiang
- Department of Pathogen Biology, School of Basic Medical Sciences, Zhengzhou University, Zhengzhou 450001, PR China.
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2
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Kim I, Leblanc J, Moreau P, Kyhm K, Dupont A, Wang I. Optical nanotopography of fluorescent surfaces by axial position modulation. OPTICS EXPRESS 2022; 30:6425-6439. [PMID: 35209581 DOI: 10.1364/oe.451896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 02/04/2022] [Indexed: 06/14/2023]
Abstract
We present an optical method that combines confocal microscopy with position modulation to perform axial tracking and topographic imaging of fluorescent surfaces. Using a remote focusing system, the confocal observation volume is oscillated in the axial direction. The resulting modulation of the detected signal is used as a feedback to precisely control the distance to an object of interest. The accuracy of this method is theoretically analyzed and the axial-locking accuracy is experimentally evaluated. Topographic imaging is demonstrated on fluorescently coated beads and fixed cells. This microscope allows for nanometric topography or tracking of dynamic fluorescent surfaces.
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3
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Trends in biomedical analysis of red blood cells – Raman spectroscopy against other spectroscopic, microscopic and classical techniques. Trends Analyt Chem 2022. [DOI: 10.1016/j.trac.2021.116481] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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4
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Glushakova S, Busse BL, Garten M, Beck JR, Fairhurst RM, Goldberg DE, Zimmerberg J. Exploitation of a newly-identified entry pathway into the malaria parasite-infected erythrocyte to inhibit parasite egress. Sci Rep 2017; 7:12250. [PMID: 28947749 PMCID: PMC5612957 DOI: 10.1038/s41598-017-12258-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 09/05/2017] [Indexed: 12/20/2022] Open
Abstract
While many parasites develop within host cells to avoid antibody responses and to utilize host cytoplasmic resources, elaborate egress processes have evolved to minimize the time between escaping and invading the next cell. In human erythrocytes, malaria parasites perforate their enclosing erythrocyte membrane shortly before egress. Here, we show that these pores clearly function as an entry pathway into infected erythrocytes for compounds that inhibit parasite egress. The natural glycosaminoglycan heparin surprisingly inhibited malaria parasite egress, trapping merozoites within infected erythrocytes. Labeled heparin neither bound to nor translocated through the intact erythrocyte membrane during parasite development, but fluxed into erythrocytes at the last minute of the parasite lifecycle. This short encounter was sufficient to significantly inhibit parasite egress and dispersion. Heparin blocks egress by interacting with both the surface of intra-erythrocytic merozoites and the inner aspect of erythrocyte membranes, preventing the rupture of infected erythrocytes but not parasitophorous vacuoles, and independently interfering with merozoite disaggregation. Since this action of heparin recapitulates that of neutralizing antibodies, membrane perforation presents a brief opportunity for a new strategy to inhibit parasite egress and replication.
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Affiliation(s)
- Svetlana Glushakova
- Section on Integrative Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Brad L Busse
- Section on Integrative Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Matthias Garten
- Section on Integrative Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Josh R Beck
- Division of Infectious Diseases, Department of Medicine, Washington University, St. Louis, MO, 63110, USA
| | - Rick M Fairhurst
- Laboratory of Malaria and Vector Research, National Institute of Allergy and Infectious Diseases; National Institutes of Health, Bethesda, MD, 20892, USA
| | - Daniel E Goldberg
- Division of Infectious Diseases, Department of Medicine, Washington University, St. Louis, MO, 63110, USA
| | - Joshua Zimmerberg
- Section on Integrative Biophysics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, 20892, USA.
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5
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Bulat K, Rygula A, Szafraniec E, Ozaki Y, Baranska M. Live endothelial cells imaged by Scanning Near-field Optical Microscopy (SNOM): capabilities and challenges. JOURNAL OF BIOPHOTONICS 2017; 10:928-938. [PMID: 27545579 DOI: 10.1002/jbio.201600081] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2016] [Revised: 07/23/2016] [Accepted: 08/05/2016] [Indexed: 06/06/2023]
Abstract
The scanning near-field optical microscopy (SNOM) shows a potential to study details of biological samples, since it provides the optical images of objects with nanometric spatial resolution (50-200 nm) and the topographic information at the same time. The goal of this work is to demonstrate the capabilities of SNOM in transmission configuration to study human endothelial cells and their morphological changes, sometimes very subtle, upon inflammation. Various sample preparations were tested for SNOM measurements and promising results are collected to show: 1) the influence of α tumor necrosis factor (TNF-α) on EA.hy 926 cells (measurements of the fixed cells); 2) high resolution images of various endothelial cell lines, i.e. EA.hy 926 and HLMVEC (investigations of the fixed cells in buffer environment); 3) imaging of live endothelial cells in physiological buffers. The study demonstrate complementarity of the SNOM measurements performed in air and in liquid environments, on fixed as well as on living cells. Furthermore, it is proved that the SNOM is a very useful method for analysis of cellular morphology and topography. Changes in the cell shape and nucleus size, which are the symptoms of inflammatory reaction, were noticed in TNF-α activated EA.hy 926 cells. The cellular structures of submicron size were observed in high resolution optical images of cells from EA.hy 926 and HLMVEC lines.
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Affiliation(s)
- Katarzyna Bulat
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, Krakow, Poland
- Jagiellonian Centre for Experimental Therapeutics (JCET), Bobrzynskiego 14, Kraków, Poland
| | - Anna Rygula
- Jagiellonian Centre for Experimental Therapeutics (JCET), Bobrzynskiego 14, Kraków, Poland
| | - Ewelina Szafraniec
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, Krakow, Poland
| | - Yukihiro Ozaki
- Kwasei Gakuin University, 2-1 Gakuen, Sanda, Hyougo, 669-1337, Japan
| | - Malgorzata Baranska
- Faculty of Chemistry, Jagiellonian University, Ingardena 3, Krakow, Poland
- Jagiellonian Centre for Experimental Therapeutics (JCET), Bobrzynskiego 14, Kraków, Poland
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6
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Mooren OL, Erickson ES, Dickenson NE, Dunn RC. Extending Near-Field Scanning Optical Microscopy for Biological Studies. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.jala.2006.05.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Near-field scanning optical microscopy (NSOM) is a scanning probe technique that enables optical measurements to be conducted with nanometric spatial resolution. In addition to high-resolution optical information, NSOM yields a topographic mapping of sample features that enables a direct comparison to be made between surface topography and the optical signal. For the biological sciences, where sophisticated fluorescence labeling protocols have been developed, the simultaneously collected fluorescence and topography information measured with NSOM offers a potentially powerful tool. The progress in implementing NSOM on unfixed, viable samples, however, has been slowed over concerns regarding sample heating and problems associated with damaging forces generated during imaging. Here, we discuss recent measurements that show sample heating to be modest and not limiting for NSOM applications on viable tissues. In addition, we highlight recent work on developing new NSOM probes that have been demonstrated to be amenable with imaging unfixed samples under buffered conditions. These developments now enable the high resolution of NSOM to be applied to areas in the biological sciences that were previously inaccessible. (JALA 2006;11:268–72)
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7
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Quantifying the Assembly of Multicomponent Molecular Machines by Single-Molecule Total Internal Reflection Fluorescence Microscopy. Methods Enzymol 2016; 581:105-145. [PMID: 27793278 PMCID: PMC5403009 DOI: 10.1016/bs.mie.2016.08.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Large, dynamic macromolecular complexes play essential roles in many cellular processes. Knowing how the components of these complexes associate with one another and undergo structural rearrangements is critical to understanding how they function. Single-molecule total internal reflection fluorescence (TIRF) microscopy is a powerful approach for addressing these fundamental issues. In this article, we first discuss single-molecule TIRF microscopes and strategies to immobilize and fluorescently label macromolecules. We then review the use of single-molecule TIRF microscopy to study the formation of binary macromolecular complexes using one-color imaging and inhibitors. We conclude with a discussion of the use of TIRF microscopy to examine the formation of higher-order (i.e., ternary) complexes using multicolor setups. The focus throughout this article is on experimental design, controls, data acquisition, and data analysis. We hope that single-molecule TIRF microscopy, which has largely been the province of specialists, will soon become as common in the tool box of biophysicists and biochemists as structural approaches have become today.
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8
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Pi J, Jin H, Yang F, Chen ZW, Cai J. In situ single molecule imaging of cell membranes: linking basic nanotechniques to cell biology, immunology and medicine. NANOSCALE 2014; 6:12229-12249. [PMID: 25227707 DOI: 10.1039/c4nr04195j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The cell membrane, which consists of a viscous phospholipid bilayer, different kinds of proteins and various nano/micrometer-sized domains, plays a very important role in ensuring the stability of the intracellular environment and the order of cellular signal transductions. Exploring the precise cell membrane structure and detailed functions of the biomolecules in a cell membrane would be helpful to understand the underlying mechanisms involved in cell membrane signal transductions, which could further benefit research into cell biology, immunology and medicine. The detection of membrane biomolecules at the single molecule level can provide some subtle information about the molecular structure and the functions of the cell membrane. In particular, information obtained about the molecular mechanisms and other information at the single molecule level are significantly different from that detected from a large amount of biomolecules at the large-scale through traditional techniques, and can thus provide a novel perspective for the study of cell membrane structures and functions. However, the precise investigations of membrane biomolecules prompts researchers to explore cell membranes at the single molecule level by the use of in situ imaging methods, as the exact conformation and functions of biomolecules are highly controlled by the native cellular environment. Recently, the in situ single molecule imaging of cell membranes has attracted increasing attention from cell biologists and immunologists. The size of biomolecules and their clusters on the cell surface are set at the nanoscale, which makes it mandatory to use high- and super-resolution imaging techniques to realize the in situ single molecule imaging of cell membranes. In the past few decades, some amazing imaging techniques and instruments with super resolution have been widely developed for molecule imaging, which can also be further employed for the in situ single molecule imaging of cell membranes. In this review, we attempt to summarize the characteristics of these advanced techniques for use in the in situ single molecule imaging of cell membranes. We believe that this work will help to promote the technological and methodological developments of super-resolution techniques for the single molecule imaging of cell membranes and help researchers better understand which technique is most suitable for their future exploring of membrane biomolecules; ultimately promoting further developments in cell biology, immunology and medicine.
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Affiliation(s)
- Jiang Pi
- State Key Laboratory of Quality Research in Chinese Medicines, Macau University of Science and Technique, Macau, China.
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Mivelle M, Van Zanten TS, Manzo C, Garcia-Parajo MF. Nanophotonic approaches for nanoscale imaging and single-molecule detection at ultrahigh concentrations. Microsc Res Tech 2014; 77:537-45. [DOI: 10.1002/jemt.22369] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/28/2014] [Accepted: 03/27/2014] [Indexed: 12/22/2022]
Affiliation(s)
- Mathieu Mivelle
- ICFO-Institut de Ciencies Fotoniques; Mediterranean Technology Park; Castelldefels 08860 Barcelona Spain
| | - Thomas. S. Van Zanten
- ICFO-Institut de Ciencies Fotoniques; Mediterranean Technology Park; Castelldefels 08860 Barcelona Spain
| | - Carlo Manzo
- ICFO-Institut de Ciencies Fotoniques; Mediterranean Technology Park; Castelldefels 08860 Barcelona Spain
| | - Maria F. Garcia-Parajo
- ICFO-Institut de Ciencies Fotoniques; Mediterranean Technology Park; Castelldefels 08860 Barcelona Spain
- ICREA-Institució Catalana de Recerca i Estudis Avançats; 08010 Barcelona Spain
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10
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Fedosov DA, Dao M, Karniadakis GE, Suresh S. Computational biorheology of human blood flow in health and disease. Ann Biomed Eng 2013; 42:368-87. [PMID: 24419829 DOI: 10.1007/s10439-013-0922-3] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Accepted: 10/02/2013] [Indexed: 11/30/2022]
Abstract
Hematologic disorders arising from infectious diseases, hereditary factors and environmental influences can lead to, and can be influenced by, significant changes in the shape, mechanical and physical properties of red blood cells (RBCs), and the biorheology of blood flow. Hence, modeling of hematologic disorders should take into account the multiphase nature of blood flow, especially in arterioles and capillaries. We present here an overview of a general computational framework based on dissipative particle dynamics (DPD) which has broad applicability in cell biophysics with implications for diagnostics, therapeutics and drug efficacy assessments for a wide variety of human diseases. This computational approach, validated by independent experimental results, is capable of modeling the biorheology of whole blood and its individual components during blood flow so as to investigate cell mechanistic processes in health and disease. DPD is a Lagrangian method that can be derived from systematic coarse-graining of molecular dynamics but can scale efficiently up to arterioles and can also be used to model RBCs down to the spectrin level. We start from experimental measurements of a single RBC to extract the relevant biophysical parameters, using single-cell measurements involving such methods as optical tweezers, atomic force microscopy and micropipette aspiration, and cell-population experiments involving microfluidic devices. We then use these validated RBC models to predict the biorheological behavior of whole blood in healthy or pathological states, and compare the simulations with experimental results involving apparent viscosity and other relevant parameters. While the approach discussed here is sufficiently general to address a broad spectrum of hematologic disorders including certain types of cancer, this paper specifically deals with results obtained using this computational framework for blood flow in malaria and sickle cell anemia.
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Affiliation(s)
- Dmitry A Fedosov
- Institute of Complex Systems and Institute for Advanced Simulation, Forschungszentrum Jülich, 52425, Jülich, Germany
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11
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Deckert V, Zeisel D, Zenobi R, Vo-Dinh T. Near-Field Surface-Enhanced Raman Imaging of Dye-Labeled DNA with 100-nm Resolution. Anal Chem 2012; 70:2646-50. [PMID: 21644784 DOI: 10.1021/ac971304f] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Raman chemical imaging on a scale of 100 nm is demonstrated for the first time. This is made possible by the combination of scanning near-field optical microscopy (SNOM or NSOM) and surface-enhanced Raman scattering (SERS), using brilliant cresyl blue (BCB)-labeled DNA as a sample. SERS substrates were produced by evaporating silver layers on Teflon nanospheres. The near-field SERS spectra were measured with an exposure time of 60 s and yielded good signal-to-noise ratios (25:1). The distinction between reflected light from the excitation laser and Raman scattered light allows the local sample reflectivity to be separated from the signal of the adsorbed DNA molecules. This is of general importance to correct for topographic coupling that often occurs in near-field optical imaging. The presented data show a lateral dependence of the Raman signals that points to special surface sites with particularly high SERS enhancement.
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Affiliation(s)
- V Deckert
- Laboratorium für Organische Chemie, ETH Zürich, Universitätsstrasse 16, CH-8092 Zürich, Switzerland
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12
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Hinterdorfer P, Garcia-Parajo MF, Dufrêne YF. Single-molecule imaging of cell surfaces using near-field nanoscopy. Acc Chem Res 2012; 45:327-36. [PMID: 21992025 DOI: 10.1021/ar2001167] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Living cells use surface molecules such as receptors and sensors to acquire information about and to respond to their environments. The cell surface machinery regulates many essential cellular processes, including cell adhesion, tissue development, cellular communication, inflammation, tumor metastasis, and microbial infection. These events often involve multimolecular interactions occurring on a nanometer scale and at very high molecular concentrations. Therefore, understanding how single-molecules localize, assemble, and interact on the surface of living cells is an important challenge and a difficult one to address because of the lack of high-resolution single-molecule imaging techniques. In this Account, we show that atomic force microscopy (AFM) and near-field scanning optical microscopy (NSOM) provide unprecedented possibilities for mapping the distribution of single molecules on the surfaces of cells with nanometer spatial resolution, thereby shedding new light on their highly sophisticated functions. For single-molecule recognition imaging by AFM, researchers label the tip with specific antibodies or ligands and detect molecular recognition signals on the cell surface using either adhesion force or dynamic recognition force mapping. In single-molecule NSOM, the tip is replaced by an optical fiber with a nanoscale aperture. As a result, topographic and optical images are simultaneously generated, revealing the spatial distribution of fluorescently labeled molecules. Recently, researchers have made remarkable progress in the application of near-field nanoscopy to image the distribution of cell surface molecules. Those results have led to key breakthroughs: deciphering the nanoscale architecture of bacterial cell walls; understanding how cells assemble surface receptors into nanodomains and modulate their functional state; and understanding how different components of the cell membrane (lipids, proteins) assemble and communicate to confer efficient functional responses upon cell activation. We anticipate that the next steps in the evolution of single-molecule near-field nanoscopy will involve combining single-molecule imaging with single-molecule force spectroscopy to simultaneously measure the localization, elasticity, and interactions of cell surface molecules. In addition, progress in high-speed AFM should allow researchers to image single cell surface molecules at unprecedented temporal resolution. In parallel, exciting advances in the fields of photonic antennas and plasmonics may soon find applications in cell biology, enabling true nanoimaging and nanospectroscopy of individual molecules in living cells.
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Affiliation(s)
- Peter Hinterdorfer
- Institute for Biophysics, Christian
Doppler Laboratory of Nanoscopic Methods in Biophysics, Johannes Kepler University Linz, Altenbergerstrasse
69, A-4040 Linz, Austria
| | - Maria F. Garcia-Parajo
- ICFO-The Institute of Photonic Sciences, Mediterranean Technology Park,
08860 Castelldefels (Barcelona), Spain, and ICREA-Institució Catalana de Recerca i Estudis Avançats, 08010
Barcelona, Spain
| | - Yves F. Dufrêne
- Institute of Condensed Matter
and Nanosciences, Université catholique de Louvain, Croix du Sud 2/18, B-1348 Louvain-la-Neuve, Belgium
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13
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Abstract
Cells respond to biochemical and mechanical stimuli through a series of steps that begin at the molecular, nanometre level, and translate finally in global cell response. Defects in biochemical- and/or mechanical-sensing, transduction or cellular response are the cause of multiple diseases, including cancer and immune disorders among others. Within the booming field of regenerative medicine, there is an increasing need for developing and applying nanotechnology tools to bring understanding on the cellular machinery and molecular interactions at the nanoscale. Nanotechnology, nanophotonics and in particular, high-resolution-based fluorescence approaches are already delivering crucial information on the way that cells respond to their environment and how they organize their receptors to perform specialized functions. This chapter focuses on emerging super-resolution optical techniques, summarizing their principles, technical implementation, and reviewing some of the achievements reached so far.
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Affiliation(s)
- Maria F Garcia-Parajo
- BioNanoPhotonics Group, IBEC - Institute for Bioengineering of Catalonia and CIBER-BBN, Barcelona, Spain.
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15
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Semrau S, Holtzer L, González-Gaitán M, Schmidt T. Quantification of biological interactions with particle image cross-correlation spectroscopy (PICCS). Biophys J 2011; 100:1810-8. [PMID: 21463595 PMCID: PMC3072609 DOI: 10.1016/j.bpj.2010.12.3746] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 11/24/2010] [Accepted: 12/23/2010] [Indexed: 12/30/2022] Open
Abstract
A multitude of biological processes that involve multiple interaction partners are observed by two-color microscopy. Here we describe an analysis method for the robust quantification of correlation between signals in different color channels: particle image cross-correlation spectroscopy (PICCS). The method, which exploits the superior positional accuracy obtained in single-object and single-molecule microscopy, can extract the correlation fraction and length scale. We applied PICCS to correlation measurements in living tissues. The morphogen Decapentaplegic (Dpp) was imaged in wing imaginal disks of fruit fly larvae and we quantified what fraction of early endosomes contained Dpp.
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Affiliation(s)
- Stefan Semrau
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands
| | - Laurent Holtzer
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands
| | | | - Thomas Schmidt
- Physics of Life Processes, Leiden Institute of Physics, Leiden University, Leiden, The Netherlands
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16
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Bow H, Pivkin I, Diez-Silva M, Goldfless SJ, Dao M, Niles JC, Suresh S, Han J. A microfabricated deformability-based flow cytometer with application to malaria. LAB ON A CHIP 2011; 11:1065-73. [PMID: 21293801 PMCID: PMC3366288 DOI: 10.1039/c0lc00472c] [Citation(s) in RCA: 159] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Malaria resulting from Plasmodium falciparum infection is a major cause of human suffering and mortality. Red blood cell (RBC) deformability plays a major role in the pathogenesis of malaria. Here we introduce an automated microfabricated "deformability cytometer" that measures dynamic mechanical responses of 10(3) to 10(4) individual RBCs in a cell population. Fluorescence measurements of each RBC are simultaneously acquired, resulting in a population-based correlation between biochemical properties, such as cell surface markers, and dynamic mechanical deformability. This device is especially applicable to heterogeneous cell populations. We demonstrate its ability to mechanically characterize a small number of P. falciparum-infected (ring stage) RBCs in a large population of uninfected RBCs. Furthermore, we are able to infer quantitative mechanical properties of individual RBCs from the observed dynamic behavior through a dissipative particle dynamics (DPD) model. These methods collectively provide a systematic approach to characterize the biomechanical properties of cells in a high-throughput manner.
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Affiliation(s)
- Hansen Bow
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
| | - Igor Pivkin
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
| | - Monica Diez-Silva
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
| | - Stephen J. Goldfless
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
| | - Ming Dao
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
| | - Jacquin C. Niles
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
| | - Subra Suresh
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
| | - Jongyoon Han
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
- Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139
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Chiono V, Descrovi E, Sartori S, Gentile P, Ballarini M, Giorgis F, Ciardelli G. Biomimetic Tailoring of the Surface Properties of Polymers at the Nanoscale: Medical Applications. SCANNING PROBE MICROSCOPY IN NANOSCIENCE AND NANOTECHNOLOGY 2 2011. [DOI: 10.1007/978-3-642-10497-8_22] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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18
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Jeon IT, Cho MK, Cho JW, An BH, Wu JH, Kringel R, Choi DS, Kim YK. Ni–Au core–shell nanowires: synthesis, microstructures, biofunctionalization, and the toxicological effects on pancreatic cancer cells. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm11143d] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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A nanometer scale optical view on the compartmentalization of cell membranes. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2010; 1798:777-87. [DOI: 10.1016/j.bbamem.2009.09.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2009] [Revised: 09/13/2009] [Accepted: 09/20/2009] [Indexed: 12/30/2022]
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20
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Novel approaches for scanning near-field optical microscopy imaging of oligodendrocytes in culture. Neuroimage 2010; 49:517-24. [DOI: 10.1016/j.neuroimage.2009.07.035] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Accepted: 07/15/2009] [Indexed: 11/22/2022] Open
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21
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Herrmann M, Neuberth N, Wissler J, Pérez J, Gradl D, Naber A. Near-field optical study of protein transport kinetics at a single nuclear pore. NANO LETTERS 2009; 9:3330-3336. [PMID: 19591452 DOI: 10.1021/nl901598z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The kinetics of proteins passing through individual nuclear pore complexes (NPCs) of the nuclear envelope (NE) was studied using near-field scanning optical microscopy (NSOM) in combination with fluorescence correlation spectroscopy (FCS). The NSOM probe was placed over a single pore in an unsupported native NE to observe fluorescence-labeled NTF2 moving in the transport channel. A correlation analysis of the arising fluorescence fluctuations enabled us to characterize the translocation as driven by Brownian motion and to determine the related kinetic constants. Though trapped in the pore, NTF2 turned out to be highly mobile within a large axial extension. Our findings support the idea that molecules in transit interact with NPC proteins containing phenylalanine-glycine-repeat domains at the periphery of the channel. NSOM-FCS may help to understand the facilitated translocation in more detail and offers a new way to study single molecule mobility on a nanoscale.
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Affiliation(s)
- Michael Herrmann
- DFG-Center for Functional Nanostructures (CFN), Universität Karlsruhe (TH), Wolfgang-Gaede-Strasse 1, D-76131 Karlsruhe, Germany
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22
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LeDue JM, Lopez-Ayon M, Burke SA, Miyahara Y, Grütter P. High Q optical fiber tips for NC-AFM in liquid. NANOTECHNOLOGY 2009; 20:264018. [PMID: 19509445 DOI: 10.1088/0957-4484/20/26/264018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Non-contact atomic force microscopy is rapidly expanding from ultra-high vacuum to include the study of surfaces and biomolecules in liquids by high resolution imaging and force spectroscopy. This is despite the additional frequency shift noise due to the inherently low Q factor of the cantilever oscillating in a liquid. In this paper we present a tip based on an optical fiber which can operate in liquid with Q factors in excess of 100 using a 'diving bell' arrangement which allows only a small portion of the tip to be submerged. We demonstrate stable imaging and force spectroscopy using this set-up. The tips are based on scanning near-field optical microscopy tips and, when used with NC-AFM, provide a method of combining both high resolution mechanical and fluorescence studies of biomolecules and cells.
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Affiliation(s)
- J M LeDue
- Center for the Physics of Materials and Department of Physics, McGill University, Montreal, QC, H3A 2T8, Canada.
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23
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Zhong L, Zeng G, Lu X, Wang RC, Gong G, Yan L, Huang D, Chen ZW. NSOM/QD-based direct visualization of CD3-induced and CD28-enhanced nanospatial coclustering of TCR and coreceptor in nanodomains in T cell activation. PLoS One 2009; 4:e5945. [PMID: 19536289 PMCID: PMC2693923 DOI: 10.1371/journal.pone.0005945] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2009] [Accepted: 05/21/2009] [Indexed: 12/04/2022] Open
Abstract
Direct molecular imaging of nano-spatial relationship between T cell receptor (TCR)/CD3 and CD4 or CD8 co-receptor before and after activation of a primary T cell has not been reported. We have recently innovated application of near-field scanning optical microscopy (NSOM) and immune-labeling quantum dots (QD) to image Ag-specific TCR response during in vivo clonal expansion, and now up-graded the NSOM/QD-based nanotechnology through dipole-polarization and dual-color imaging. Using this imaging system scanning cell-membrane molecules at a best-optical lateral resolution, we demonstrated that CD3, CD4 or CD8 molecules were distinctly distributed as single QD-bound molecules or nano-clusters equivalent to 2–4 QD fluorescence-intensity/size on cell-membrane of un-stimulated primary T cells, and ∼6–10% of CD3 were co-clustering with CD4 or CD8 as 70–110 nm nano-clusters without forming nano-domains. The ligation of TCR/CD3 on CD4 or CD8 T cells led to CD3 nanoscale co-clustering or interaction with CD4 or CD8 co-receptors forming 200–500 nm nano-domains or >500 nm micro-domains. Such nano-spatial co-clustering of CD3 and CD4 or CD3 and CD8 appeared to be an intrinsic event of TCR/CD3 ligation, not purely limited to MHC engagement, and be driven by Lck phosphorylation. Importantly, CD28 co-stimulation remarkably enhanced TCR/CD3 nanoscale co-clustering or interaction with CD4 co-receptor within nano- or micro-domains on the membrane. In contrast, CD28 co-stimulation did not enhance CD8 clustering or CD3–CD8 co-clustering in nano-domains although it increased molecular number and density of CD3 clustering in the enlarged nano-domains. These nanoscale findings provide new insights into TCR/CD3 interaction with CD4 or CD8 co-receptor in T-cell activation.
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Affiliation(s)
- Liyun Zhong
- Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Gucheng Zeng
- Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Xiaoxu Lu
- School for Information and Optoelectronic Engineering, South China Normal University, Guangzhou, Guangdong, China
| | - Richard C. Wang
- Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Guangming Gong
- Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Lin Yan
- Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Dan Huang
- Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Zheng W. Chen
- Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- * E-mail:
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Chen Y, Qin J, Chen ZW. Fluorescence-topographic NSOM directly visualizes peak-valley polarities of GM1/GM3 rafts in cell membrane fluctuations. J Lipid Res 2008; 49:2268-75. [PMID: 18603643 DOI: 10.1194/jlr.d800031-jlr200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Simultaneous fluorescence-topographic nanoscale imaging of cell-surface molecules in the context of membrane ultra-structures has not been reported. Here, near-field scanning optical microscopy (NSOM)-based direct fluorescence-topographic imaging indicated that GM3 rafts/nanodomains (190.0 +/- 49.8 nm ranging 84.5-365.0 nm) were localized predominantly on the peaks of microvillus-like protrusions in the apical membrane of GM3 + Madin-Darby canine kidney cells, whereas GM1 rafts/nanodomains (159.5 +/- 63.8 nm ranging 42-360 nm) were distributed mainly on the slops of protrusions or the valleys between protrusions in the plasma membranes of GM1 + MDCK cells. The data demonstrated that gangliosides polarized not only in a well-known apical-basolateral manner but also in the more microscopic peak-valley manner, implicating unique distribution of GM1 or GM3 in cell-surface fluctuations on the apical membrane of polarized cells. The peak-valley polarities of gangliosides also implicated their different functions relevant to lipid rafts, microvilli, or cellular processes. Importantly, our study demonstrated for the first time that the NSOM-based direct fluorescence-topographic imaging is unique and powerful for elucidating nanoscale distribution of specific cell-surface molecules in membrane fluctuations.
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Affiliation(s)
- Yong Chen
- Department of Microbiology and Immunology, Center for Primate Biomedical Research, University of Illinois College of Medicine, Chicago, Illinois, USA
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25
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Müller DJ, Wu N, Palczewski K. Vertebrate membrane proteins: structure, function, and insights from biophysical approaches. Pharmacol Rev 2008; 60:43-78. [PMID: 18321962 DOI: 10.1124/pr.107.07111] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Membrane proteins are key targets for pharmacological intervention because they are vital for cellular function. Here, we analyze recent progress made in the understanding of the structure and function of membrane proteins with a focus on rhodopsin and development of atomic force microscopy techniques to study biological membranes. Membrane proteins are compartmentalized to carry out extra- and intracellular processes. Biological membranes are densely populated with membrane proteins that occupy approximately 50% of their volume. In most cases membranes contain lipid rafts, protein patches, or paracrystalline formations that lack the higher-order symmetry that would allow them to be characterized by diffraction methods. Despite many technical difficulties, several crystal structures of membrane proteins that illustrate their internal structural organization have been determined. Moreover, high-resolution atomic force microscopy, near-field scanning optical microscopy, and other lower resolution techniques have been used to investigate these structures. Single-molecule force spectroscopy tracks interactions that stabilize membrane proteins and those that switch their functional state; this spectroscopy can be applied to locate a ligand-binding site. Recent development of this technique also reveals the energy landscape of a membrane protein, defining its folding, reaction pathways, and kinetics. Future development and application of novel approaches during the coming years should provide even greater insights to the understanding of biological membrane organization and function.
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Affiliation(s)
- Daniel J Müller
- Biotechnology Center, University of Technology, Dresden, Germany
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26
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De Keijzer S, Snaar-Jagalska BE, Spaink HP, Schmidt T. Single-Molecule Imaging of Cellular Signaling. SINGLE MOLECULES AND NANOTECHNOLOGY 2008. [DOI: 10.1007/978-3-540-73924-1_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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27
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Quantum Optics: Colloidal Fluorescent Semiconductor Nanocrystals (Quantum Dots) in Single-Molecule Detection and Imaging. ACTA ACUST UNITED AC 2008. [DOI: 10.1007/978-3-540-73924-1_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
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28
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Dual-color superresolution imaging of genetically expressed probes within individual adhesion complexes. Proc Natl Acad Sci U S A 2007; 104:20308-13. [PMID: 18077327 DOI: 10.1073/pnas.0710517105] [Citation(s) in RCA: 377] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Accurate determination of the relative positions of proteins within localized regions of the cell is essential for understanding their biological function. Although fluorescent fusion proteins are targeted with molecular precision, the position of these genetically expressed reporters is usually known only to the resolution of conventional optics ( approximately 200 nm). Here, we report the use of two-color photoactivated localization microscopy (PALM) to determine the ultrastructural relationship between different proteins fused to spectrally distinct photoactivatable fluorescent proteins (PA-FPs). The nonperturbative incorporation of these endogenous tags facilitates an imaging resolution in whole, fixed cells of approximately 20-30 nm at acquisition times of 5-30 min. We apply the technique to image different pairs of proteins assembled in adhesion complexes, the central attachment points between the cytoskeleton and the substrate in migrating cells. For several pairs, we find that proteins that seem colocalized when viewed by conventional optics are resolved as distinct interlocking nano-aggregates when imaged via PALM. The simplicity, minimal invasiveness, resolution, and speed of the technique all suggest its potential to directly visualize molecular interactions within cellular structures at the nanometer scale.
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NSOM/QD-based nanoscale immunofluorescence imaging of antigen-specific T-cell receptor responses during an in vivo clonal Vγ2Vδ2 T-cell expansion. Blood 2007; 111:4220-32. [PMID: 18039956 DOI: 10.1182/blood-2007-07-101691] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Nanoscale imaging of an in vivo antigen-specific T-cell immune response has not been reported. Here, the combined near-field scanning optical microscopy- and fluorescent quantum dot-based nanotechnology was used to perform immunofluorescence imaging of antigen-specific T-cell receptor (TCR) response in an in vivo model of clonal T-cell expansion. The near-field scanning optical microscopy/quantum dot system provided a best-optical-resolution (<50 nm) nano-scale imaging of Vgamma2Vdelta2 TCR on the membrane of nonstimulated Vgamma2Vdelta2 T cells. Before Ag-induced clonal expansion, these nonstimulating Vgamma2Vdelta2 TCRs appeared to be distributed differently from their alphabeta TCR counterparts on the cell surface. Surprisingly, Vgamma2Vdelta2 TCR nanoclusters not only were formed but also sustained on the membrane during an in vivo clonal expansion of Vgamma2Vdelta2 T cells after phosphoantigen treatment or phosphoantigen plus mycobacterial infection. The TCR nanoclusters could array to form nanodomains or microdomains on the membrane of clonally expanded Vgamma2Vdelta2 T cells. Interestingly, expanded Vgamma2Vdelta2 T cells bearing TCR nanoclusters or nanodomains were able to rerecognize phosphoantigen and to exert better effector function. These studies provided nanoscale insight into the in vivo T-cell immune response.
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30
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Trivedi NS, Wang HW, Nieminen AL, Oleinick NL, Izatt JA. Quantitative Analysis of Pc 4 Localization in Mouse Lymphoma (LY-R) Cells via Double-label Confocal Fluorescence Microscopy. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2000)0710634qaopli2.0.co2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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31
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Hausmann M, Perner B, Rapp A, Wollweber L, Scherthan H, Greulich KO. Near-field scanning optical microscopy in cell biology and cytogenetics. Methods Mol Biol 2006; 319:275-94. [PMID: 16719361 DOI: 10.1007/978-1-59259-993-6_14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Light microscopy has proven to be one of the most versatile analytical tools in cell biology and cytogenetics. The growing spectrum of scientific knowledge demands a continuous improvement of the optical resolution of the instruments. In far-field light microscopy, the attainable resolution is dictated by the limit of diffraction, which, in practice, is about 250 nm for high-numerical-aperture objective lenses. Near-field scanning optical microscopy (NSOM) was the first technique that has overcome this limit up to about one order of magnitude. Typically, the resolution range below 100 nm is accessed for biological applications. Using appropriately designed scanning probes allows for obtaining an extremely small near-field light excitation volume (some tens of nanometers in diameter). Because of the reduction of background illumination, high contrast imaging becomes feasible for light transmission and fluorescence microscopy. The height of the scanning probe is controlled by atomic force interactions between the specimen surface and the probe tip. The control signal can be used for the production of a topographic (nonoptical) image that can be acquired simultaneously. In this chapter, the principle of NSOM is described with respect to biological applications. A brief overview of some requirements in biology and applications described in the literature are given. Practical advice is focused on instruments with aperture-type illumination probes. Preparation protocols focussing on NSOM of cell surfaces and chromosomes are presented.
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Affiliation(s)
- Michael Hausmann
- Kirchoff Institute of Physics, University of Heidelberg, Germany
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32
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Tinnefeld P, Sauer M. Branching Out of Single‐Molecule Fluorescence Spectroscopy: Challenges for Chemistry and Influence on Biology. Angew Chem Int Ed Engl 2005; 44:2642-2671. [PMID: 15849689 DOI: 10.1002/anie.200300647] [Citation(s) in RCA: 182] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In the last decade emerging single-molecule fluorescence-spectroscopy tools have been developed and adapted to analyze individual molecules under various conditions. Single-molecule-sensitive optical techniques are now well established and help to increase our understanding of complex problems in different disciplines ranging from materials science to cell biology. Previous dreams, such as the monitoring of the motility and structural changes of single motor proteins in living cells or the detection of single-copy genes and the determination of their distance from polymerase molecules in transcription factories in the nucleus of a living cell, no longer constitute unsolvable problems. In this Review we demonstrate that single-molecule fluorescence spectroscopy has become an independent discipline capable of solving problems in molecular biology. We outline the challenges and future prospects for optical single-molecule techniques which can be used in combination with smart labeling strategies to yield quantitative three-dimensional information about the dynamic organization of living cells.
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Affiliation(s)
- Philip Tinnefeld
- Applied Laserphysics und Laserspectroscopy, Faculty of Physics, University of Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany, Fax: (+49) 521-106-2958
| | - Markus Sauer
- Applied Laserphysics und Laserspectroscopy, Faculty of Physics, University of Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany, Fax: (+49) 521-106-2958
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33
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Tinnefeld P, Sauer M. Neue Wege in der Einzelmolekül-Fluoreszenzspektroskopie: Herausforderungen für die Chemie und Einfluss auf die Biologie. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200300647] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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34
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Rasmussen A, Deckert V. New dimension in nano-imaging: breaking through the diffraction limit with scanning near-field optical microscopy. Anal Bioanal Chem 2004; 381:165-72. [PMID: 15551072 DOI: 10.1007/s00216-004-2896-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2004] [Revised: 10/08/2004] [Accepted: 10/12/2004] [Indexed: 11/29/2022]
Abstract
In recent years scanning near-field optical microscopy (SNOM) has developed into a powerful surface analytical technique for observing specimens with lateral resolution equal to or even better than 100 nm. A large number of applications, from material science to biology, have been reported. In this paper, two different kinds of near-field optical microscopy, aperture and scattering-type SNOM, are reviewed together with recent studies in surface analysis and biology. Here, near-field optical techniques are discussed in comparison with related methods, such as scanning probe and standard optical microscopy, with respect to their specific advantages and fields of application.
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Affiliation(s)
- Akiko Rasmussen
- ISAS-Institute for Analytical Sciences, Bunsen-Kirchhoff-Str. 11, 44139 Dortmund, Germany
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35
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Ianoul A, Street M, Grant D, Pezacki J, Taylor RS, Johnston LJ. Near-field scanning fluorescence microscopy study of ion channel clusters in cardiac myocyte membranes. Biophys J 2004; 87:3525-35. [PMID: 15339803 PMCID: PMC1304818 DOI: 10.1529/biophysj.104.046383] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Near-field scanning optical microscopy (NSOM) has been used to study the nanoscale distribution of voltage-gated L-type Ca2+ ion channels, which play an important role in cardiac function. NSOM fluorescence imaging of immunostained cardiac myocytes (H9C2 cells) demonstrates that the ion channel is localized in small clusters with an average diameter of 100 nm. The clusters are randomly distributed throughout the cell membrane, with some larger fluorescent patches that high-resolution images show to consist of many small closely-spaced clusters. We have imaged unstained cells to assess the contribution of topography-induced artifacts and find that the topography-induced signal is <10% of the NSOM fluorescence intensity. We have also examined the dependence of the NSOM signal intensity on the tip-sample separation to assess the contributions from fluorophores that are significantly below the cell surface. This indicates that chromophores > approximately 200 nm below the probe will have negligible contributions to the observed signal. The ability to quantitatively measure small clusters of ion channels will facilitate future studies that examine changes in protein localization in stimulated cells and during cardiac development. Our work illustrates the potential of NSOM for studying membrane domains and protein localization/colocalization on a length scale which exceeds that available with optical microscopy.
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Affiliation(s)
- Anatoli Ianoul
- Steacie Institute for Molecular Sciences and Institute for Microstructural Sciences, National Research Council Canada, Ottawa, Ontario, Canada
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36
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Sluyter R, Shemon AN, Barden JA, Wiley JS. Extracellular ATP increases cation fluxes in human erythrocytes by activation of the P2X7 receptor. J Biol Chem 2004; 279:44749-55. [PMID: 15304508 DOI: 10.1074/jbc.m405631200] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Canine erythrocytes are known to undergo a reversible increase in cation permeability when incubated with extracellular ATP. We have examined the expression and function of P2X receptors on human erythrocytes using confocal microscopy and a panel of anti-P2X(1-7) antibodies and have measured monovalent cation fluxes in the presence of various nucleotide agonists. Human erythrocytes expressed P2X7 receptors on all cells examined from eight of eight subjects, as well as P2X2 at a far lower staining intensity in six of eight subjects. ATP stimulated the efflux of 86Rb+ (K+) from human erythrocytes in a dose-dependent fashion with an EC50 of approximately 95 microM. Other nucleotides also induced an efflux of 86Rb+ from erythrocytes with an order of agonist potency of 2'- and 3'-O(4-benzoylbenzoyl) ATP (BzATP) > ATP > 2-methylthio-ATP (2MeSATP) > adenosine 5'-O-(3-thiotriphosphate) (ATPgammaS), whereas ADP or UTP had no effect. ATP-induced efflux of 86Rb+ from erythrocytes was inhibited by extracellular Na+ and oxidized ATP, as well as by KN-62, an antagonist specific for the human P2X7 receptor. When erythrocytes were incubated in isotonic KCl medium, the addition of ATP stimulated an 86Rb+ influx approximately equal in magnitude to ATP-stimulated 86Rb+ efflux from the same cells. BzATP also stimulated the influx of 22Na+ into erythrocytes incubated in isotonic NaCl medium. Both ATP-induced efflux and influx of 86Rb+ and 22Na+ were impaired in erythrocytes from subjects who had inherited loss-of-function polymorphisms in the P2X7 receptor. These results suggest that the reversible permeabilization of erythrocytes by extracellular ATP is mediated by the P2X7 receptor.
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Affiliation(s)
- Ronald Sluyter
- Department of Medicine, University of Sydney at Nepean Hospital, Penrith, New South Wales 2750, Australia
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37
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Koopman M, Cambi A, de Bakker BI, Joosten B, Figdor CG, van Hulst NF, Garcia-Parajo MF. Near-field scanning optical microscopy in liquid for high resolution single molecule detection on dendritic cells. FEBS Lett 2004; 573:6-10. [PMID: 15327966 DOI: 10.1016/j.febslet.2004.07.035] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2004] [Revised: 06/14/2004] [Accepted: 07/06/2004] [Indexed: 11/27/2022]
Abstract
Clustering of cell surface receptors into micro-domains in the plasma membrane is an important mechanism for regulating cellular functions. Unfortunately, these domains are often too small to be resolved with conventional optical microscopy. Near-field scanning optical microscopy (NSOM) is a relatively new technique that combines ultra high optical resolution, down to 70 nm, with single molecule detection sensitivity. As such, the technique holds great potential for direct visualisation of domains at the cell surface. Yet, NSOM operation under liquid conditions is far from trivial. In this contribution, we show that the performance of NSOM can be extended to measurements in liquid environments using a diving bell concept. For the first time, individual fluorescent molecules on the membrane of cells in solution are imaged with a spatial resolution of 90 nm. Furthermore, using this technique we have been able to directly visualise nanometric sized domains of the C-type lectin DC-SIGN on the membrane of dendritic cells, both in air and in liquid.
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Affiliation(s)
- M Koopman
- Applied Optics group, Faculty of Science and Technology and MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
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38
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Ebenstein Y, Mokari T, Banin U. Quantum-Dot-Functionalized Scanning Probes for Fluorescence-Energy-Transfer-Based Microscopy. J Phys Chem B 2003. [DOI: 10.1021/jp036135j] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Y. Ebenstein
- Institute of Chemistry, the Farkas Center for Light Induced Processes, and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - T. Mokari
- Institute of Chemistry, the Farkas Center for Light Induced Processes, and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | - U. Banin
- Institute of Chemistry, the Farkas Center for Light Induced Processes, and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
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39
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Morrison IEG, Karakikes I, Barber RE, Fernández N, Cherry RJ. Detecting and quantifying colocalization of cell surface molecules by single particle fluorescence imaging. Biophys J 2003; 85:4110-21. [PMID: 14645098 PMCID: PMC1303710 DOI: 10.1016/s0006-3495(03)74823-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2003] [Accepted: 08/15/2003] [Indexed: 01/14/2023] Open
Abstract
Single particle fluorescence imaging (SPFI) uses the high sensitivity of fluorescence to visualize individual molecules that have been selectively labeled with small fluorescent particles. The positions of particles are determined by fitting the intensity profile of their images to a 2-D Gaussian function. We have exploited the positional information obtained from SPFI to develop a method for detecting colocalization of cell surface molecules. This involves labeling two different molecules with different colored fluorophores and determining their positions separately by dual wavelength imaging. The images are analyzed to quantify the overlap of the particle images and hence determine the extent of colocalization of the labeled molecules. Simulated images and experiments with a model system are used to investigate the extent to which colocalization occurs from chance proximity of randomly distributed molecules. A method of correcting for positional shifts that result from chromatic aberration is presented. The technique provides quantification of the extent of colocalization and can detect whether colocalized molecules occur singly or in clusters. We have obtained preliminary data for colocalization of molecules on intact cells. Cells often exhibit particulate autofluorescence that can interfere with the measurements; a method for overcoming this problem by triple wavelength imaging is described.
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Affiliation(s)
- Ian E G Morrison
- Department of Biological Sciences, University of Essex, Colchester, CO4 3SQ, UK
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Michalet X, Kapanidis AN, Laurence T, Pinaud F, Doose S, Pflughoefft M, Weiss S. The power and prospects of fluorescence microscopies and spectroscopies. ANNUAL REVIEW OF BIOPHYSICS AND BIOMOLECULAR STRUCTURE 2003; 32:161-82. [PMID: 12598370 DOI: 10.1146/annurev.biophys.32.110601.142525] [Citation(s) in RCA: 180] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recent years have witnessed a renaissance of fluorescence microscopy techniques and applications, from live-animal multiphoton confocal microscopy to single-molecule fluorescence spectroscopy and imaging in living cells. These achievements have been made possible not so much because of improvements in microscope design, but rather because of development of new detectors, accessible continuous wave and pulsed laser sources, sophisticated multiparameter analysis on one hand, and the development of new probes and labeling chemistries on the other. This review tracks the lineage of ideas and the evolution of thinking that have led to the actual developments, and presents a comprehensive overview of the field, with emphasis put on our laboratory's interest in single-molecule microscopy and spectroscopy.
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Affiliation(s)
- Xavier Michalet
- Department of Chemistry and Biochemistry, UCLA, Young Hall, 607 Charles E. Young Drive East, Los Angeles, California 90095, USA.
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Abstract
The investigation of biomolecules has entered a new age since the development of methodologies capable of studies at the level of single molecules. In biology, most molecules show a complex dynamical behavior, with individual motions and transitions between different states occurring highly correlated in space and time within an arrangement of various elements. Recent advances in the development of new microscopy techniques with sensitivity at the single molecule have gained access to essentially new types of information obtainable from imaging biomolecular samples. These methodologies are described here in terms of their applicability to the in vivo detection and visualization of molecular processes on surfaces, membranes, and cells. First examples of single molecule microscopy on cell membranes revealed new basic insight into the lateral organization of the plasma membrane, providing the captivating perspective of an ultra-sensitive methodology as a general tool to study local processes and heterogeneities in living cells.
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Affiliation(s)
- G J Schütz
- Institute for Biophysics, University of Linz, Altenbergerstr. 69, A-4040 Linz, Austria.
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Heilemann M, Herten DP, Heintzmann R, Cremer C, Muller C, Tinnefeld P, Weston KD, Wolfrum J, Sauer M. High-resolution colocalization of single dye molecules by fluorescence lifetime imaging microscopy. Anal Chem 2002; 74:3511-7. [PMID: 12139062 DOI: 10.1021/ac025576g] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Conventional fluorescence microscopy can be used to determine the positions of objects in space when those objects are separated by distances greater than several hundred nanometers, as restricted by the diffraction limit of light. Fluorescence microscopy/spectroscopy based on fluorescence resonance energy-transfer techniques can be used to measure separation distances below approximately 10 nm. To fill the gap between these fundamental limits, we have developed an alternative technique for high-resolution colocalization of fluorescent dyes. The technique is based on fluorescence lifetime imaging. Under favorable conditions, the method can be used to distinguish, and to measure the distance between, two dye molecules that are less than 30 nm apart. To demonstrate the method, lifetime images of a mixture of Cy5 and JF9 (rhodamine derivative) molecules statistically adsorbed on a glass surface were acquired and analyzed. Since these two molecular species differ in fluorescence lifetime (for Cy5, tau(f) = 2.0 ns, and for JF9, tau(f) = 4.0 ns), it is possible to assign the contribution of fluorescence of the two dye types to each image pixel using a pattern recognition technique. Since both dye types can be excited using the same laser wavelength, the measurement is free of chromatic aberrations. The results presented demonstrate the first high-precision distance measurements between single conventional fluorescent dyes based solely on fluorescence lifetime.
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Affiliation(s)
- Mike Heilemann
- Physikalisch-Chemisches Institut, Universität Heidelberg, Germany
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Abstract
Near-field optical analysis (NOA) provides morphological nanoscale mappings of living cells in liquid cell culture media and nondestructive insight into cell functionality. Here we show for the first time the performance of NOA in imaging living cells. Unlabeled human endothelial cells attached to polished titanium disks were analyzed with hydrophobically coated optical biosensors mounted to a near-field scanning optical microscope (NSOM). Biosensors and titanium substrates could be simply implemented in standard NSOM and high-throughput NOA.
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Affiliation(s)
- Andrei P Sommer
- Department of Biomaterials/ENSOMA-Laboratory, Central Institute of Biomedical Engineering University of Ulm, 89081 Ulm, Germany.
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de Lange F, Cambi A, Huijbens R, de Bakker B, Rensen W, Garcia-Parajo M, van Hulst N, Figdor CG. Cell biology beyond the diffraction limit: near-field scanning optical microscopy. J Cell Sci 2001; 114:4153-60. [PMID: 11739648 DOI: 10.1242/jcs.114.23.4153] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Throughout the years, fluorescence microscopy has proven to be an extremely versatile tool for cell biologists to study live cells. Its high sensitivity and non-invasiveness, together with the ever-growing spectrum of sophisticated fluorescent indicators, ensure that it will continue to have a prominent role in the future. A drawback of light microscopy is the fundamental limit of the attainable spatial resolution – ∼250 nm – dictated by the laws of diffraction. The challenge to break this diffraction limit has led to the development of several novel imaging techniques. One of them, near-field scanning optical microscopy (NSOM), allows fluorescence imaging at a resolution of only a few tens of nanometers and, because of the extremely small near-field excitation volume, reduces background fluorescence from the cytoplasm to the extent that single-molecule detection sensitivity becomes within reach. NSOM allows detection of individual fluorescent proteins as part of multimolecular complexes on the surface of fixed cells, and similar results should be achievable under physiological conditions in the near future.
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Affiliation(s)
- F de Lange
- Department of Tumor Immunology, University Medical Center Nijmegen, NCMLS/187 TIL, PO Box 9101, 6500HB Nijmegen, The Netherlands
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Abstract
Near-field illumination of a sample with visible light can resolve features well beyond the resolution of conventional, far-field microscopes. Near-field scanning optical microscopy (NSOM) then has the potential of extending the resolution of techniques such as fluorescent labeling, yielding images of cell structures and molecules on the nanoscale. However, major problems remain to be solved before NSOM can be easily used for wet biological samples. The most significant of these is control of the distance between near-field aperture and the sample surface. Hence, while NSOM promises much, its application to biology is about where electron microscopy was 40 or 50 years ago.
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Affiliation(s)
- M Edidin
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA.
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Hinterdorfer P, Schütz G, Kienberger F, Schindler H. Detection and characterization of single biomolecules at surfaces. J Biotechnol 2001; 82:25-35. [PMID: 11999710 DOI: 10.1016/s1389-0352(01)00030-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The investigation of bio-molecules has entered a new age since the development of methodologies capable of studies at the level of single molecules. In biology, most molecules show a complex dynamical behavior, with individual motions and transitions between different states, occurring as highly correlated in space and time within an arrangement of various elements. In order to resolve such dynamical changes in ensemble average techniques, one would have to synchronize all molecules, which is hard to achieve and might interfere with important system properties. Single molecule studies, in contrast, do not require pretreatment of the system and resume, therefore, much less invasive methodologies. Here, we review recent employments for the investigation of bio-molecules on surfaces, in which the high local and temporal resolution of two complementary techniques, atomic force microscopy and single molecule fluorescence microscopy, is used to address single molecules. Novel methodologies for the characterization of biologically relevant parameters, functions and dynamical aspects of individual molecules are described.
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Michalet X, Lacoste TD, Weiss S. Ultrahigh-resolution colocalization of spectrally separable point-like fluorescent probes. Methods 2001; 25:87-102. [PMID: 11559000 DOI: 10.1006/meth.2001.1218] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
An ultrahigh-resolution colocalization method based on the simultaneous acquisition and analysis of spectrally separated images of the excitation point-spread function of point-like fluorescent probes is reviewed. It is shown that molecular distances can be measured with accuracy better than 10 nm using conventional far-field optics. A detailed account of the methodology, theoretical considerations, signal processing, and data fitting algorithms is given.
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Affiliation(s)
- X Michalet
- Material Sciences Division and Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, USA
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Abstract
Here we demonstrate a new microscopic method that combines atomic force microscopy (AFM) with fluorescence resonance energy transfer (FRET). This method takes advantage of the strong distance dependence in Förster energy transfer between dyes with the appropriate donor/acceptor properties to couple an optical dimension with conventional AFM. This is achieved by attaching an acceptor dye to the end of an AFM tip and exciting a sample bound donor dye through far-field illumination. Energy transfer from the excited donor to the tip immobilized acceptor dye leads to emission in the red whenever there is sufficient overlap between the two dyes. Because of the highly exponential distance dependence in this process, only those dyes located at the apex of the AFM tip, nearest the sample, interact strongly. This limited and highly specific interaction provides a mechanism for obtaining fluorescence contrast with high spatial resolution. Initial results in which 400 nm resolution is obtained through this AFM/FRET imaging technique are reported. Future modifications in the probe design are discussed to further improve both the fluorescence resolution and imaging capabilities of this new technique.
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Affiliation(s)
- S A Vickery
- Department of Chemistry, University of Kansas, Lawrence 66045, USA
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Lacoste TD, Michalet X, Pinaud F, Chemla DS, Alivisatos AP, Weiss S. Ultrahigh-resolution multicolor colocalization of single fluorescent probes. Proc Natl Acad Sci U S A 2000; 97:9461-6. [PMID: 10931959 PMCID: PMC16886 DOI: 10.1073/pnas.170286097] [Citation(s) in RCA: 262] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An optical ruler based on ultrahigh-resolution colocalization of single fluorescent probes is described in this paper. It relies on the use of two unique families of fluorophores, namely energy-transfer fluorescent beads (TransFluoSpheres) and semiconductor nanocrystal quantum dots, that can be excited by a single laser wavelength but emit at different wavelengths. A multicolor sample-scanning confocal microscope was constructed that allows one to image each fluorescent light emitter, free of chromatic aberrations, by scanning the sample with nanometer scale steps with a piezo-scanner. The resulting spots are accurately localized by fitting them to the known shape of the excitation point-spread function of the microscope. We present results of two-dimensional colocalization of TransFluoSpheres (40 nm in diameter) and of nanocrystals (3-10 nm in diameter) and demonstrate distance-measurement accuracy of better than 10 nm using conventional far-field optics. This ruler bridges the gap between fluorescence resonance energy transfer, near- and far-field imaging, spanning a range of a few nanometers to tens of micrometers.
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Affiliation(s)
- T D Lacoste
- Material Sciences and Physical Biosciences Divisions, Lawrence Berkeley National Laboratory, CA 94720, USA
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