1
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Xu J, Sun X, Chen Z, Ma H, Liu Y. Super-resolution imaging of T lymphocyte activation reveals chromatin decondensation and disrupted nuclear envelope. Commun Biol 2024; 7:717. [PMID: 38858440 PMCID: PMC11164909 DOI: 10.1038/s42003-024-06393-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 05/23/2024] [Indexed: 06/12/2024] Open
Abstract
T lymphocyte activation plays a pivotal role in adaptive immune response and alters the spatial organization of nuclear architecture that subsequently impacts transcription activities. Here, using stochastic optical reconstruction microscopy (STORM), we observe dramatic de-condensation of chromatin and the disruption of nuclear envelope at a nanoscale resolution upon T lymphocyte activation. Super-resolution imaging reveals that such alterations in nuclear architecture are accompanied by the release of nuclear DNA into the cytoplasm, correlating with the degree of chromatin decompaction within the nucleus. The authors show that under the influence of metabolism, T lymphocyte activation de-condenses chromatin, disrupts the nuclear envelope, and releases DNA into the cytoplasm. Taken together, this result provides a direct, molecular-scale insight into the alteration in nuclear architecture. It suggests the release of nuclear DNA into the cytoplasm as a general consequence of chromatin decompaction after lymphocyte activation.
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Affiliation(s)
- Jianquan Xu
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Xuejiao Sun
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Zhangguo Chen
- UPMC Hillman Cancer Center, Division of Hematology and Oncology, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Hongqiang Ma
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA
- Department of Bioengineering, Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA
| | - Yang Liu
- Biomedical Optical Imaging Laboratory, Departments of Medicine and Bioengineering, University of Pittsburgh, Pittsburgh, PA, 15213, USA.
- Department of Bioengineering, Department of Electrical and Computer Engineering, Beckman Institute for Advanced Science and Technology, Cancer Center at Illinois, University of Illinois Urbana-Champaign, Urbana, IL, 61801, USA.
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2
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Yan Y, Zhou P, Ding L, Hu W, Chen W, Su B. T Cell Antigen Recognition and Discrimination by Electrochemiluminescence Imaging. Angew Chem Int Ed Engl 2023; 62:e202314588. [PMID: 37903724 DOI: 10.1002/anie.202314588] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 10/28/2023] [Accepted: 10/30/2023] [Indexed: 11/01/2023]
Abstract
Adoptive T lymphocyte (T cell) transfer and tumour-specific peptide vaccines are innovative cancer therapies. An accurate assessment of the specific reactivity of T cell receptors (TCRs) to tumour antigens is required because of the high heterogeneity of tumour cells and the immunosuppressive tumour microenvironment. In this study, we report a label-free electrochemiluminescence (ECL) imaging approach for recognising and discriminating between TCRs and tumour-specific antigens by imaging the immune synapses of T cells. Various T cell stimuli, including agonistic antibodies, auxiliary molecules, and tumour-specific antigens, were modified on the electrode's surface to allow for their interaction with T cells bearing different TCRs. The formation of immune synapses activated by specific stimuli produced a negative (shadow) ECL image, from which T cell antigen recognition and discrimination were evaluated by analysing the spreading area and the recognition intensity of T cells. This approach provides an easy way to assess TCR-antigen specificity and screen both of them for immunotherapies.
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Affiliation(s)
- Yajuan Yan
- Key Laboratory of Excited-State Materials of Zhejiang Province, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Ping Zhou
- Key Laboratory of Excited-State Materials of Zhejiang Province, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Lurong Ding
- Key Laboratory of Excited-State Materials of Zhejiang Province, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
| | - Wei Hu
- Kidney Disease Center, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310058, China
| | - Wei Chen
- Department of Cardiology of the Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310058, China
- Liangzhu Laboratory, Zhejiang University, Hangzhou, 311121, China
- Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Ministry of Education Frontier Science Center for Brain Science & Brain-machine Integration, State Key Laboratory for Modern Optical Instrumentation, Key Laboratory for Biomedical Engineering of the Ministry of Education, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, Zhejiang 310012, China
| | - Bin Su
- Key Laboratory of Excited-State Materials of Zhejiang Province, Department of Chemistry, Zhejiang University, Hangzhou, 310058, China
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3
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Zhao J, Liu L, Wang T, Zhang J, Wang X, Du X, Hao R, Liu J, Liu Y, Liu Y. Quantitative phase imaging of living red blood cells combining digital holographic microscopy and deep learning. JOURNAL OF BIOPHOTONICS 2023; 16:e202300090. [PMID: 37321984 DOI: 10.1002/jbio.202300090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 06/17/2023]
Abstract
Digital holographic microscopy as a non-contacting, non-invasive, and highly accurate measurement technology, is becoming a valuable method for quantitatively investigating cells and tissues. Reconstruction of phases from a digital hologram is a key step in quantitative phase imaging for biological and biomedical research. This study proposes a two-stage deep convolutional neural network named VY-Net, to realize the effective and robust phase reconstruction of living red blood cells. The VY-Net can obtain the phase information of an object directly from a single-shot off-axis digital hologram. We also propose two new indices to evaluate the reconstructed phases. In experiments, the mean of the structural similarity index of reconstructed phases can reach 0.9309, and the mean of the accuracy of reconstructions of reconstructed phases is as high as 91.54%. An unseen phase map of a living human white blood cell is successfully reconstructed by the trained VY-Net, demonstrating its strong generality.
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Affiliation(s)
- Jiaxi Zhao
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Lin Liu
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Tianhe Wang
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Jing Zhang
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiangzhou Wang
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Xiaohui Du
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Ruqian Hao
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Juanxiu Liu
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
| | - Yi Liu
- School of Physics, University of Electronic Science and Technology of China, Chengdu, China
| | - Yong Liu
- School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, China
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4
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Zhou X, Mubarak HK, Ma L, Palsgrove D, Ortega S, Callicó GM, Medina EA, Brimhall BB, Whitted M, Fei B. Polarized Hyperspectral Microscopic Imaging for White Blood Cells on Wright-Stained Blood Smear Slides. PROCEEDINGS OF SPIE--THE INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING 2023; 12382:1238207. [PMID: 38486823 PMCID: PMC10938460 DOI: 10.1117/12.2655708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/17/2024]
Abstract
White blood cells, also called leukocytes, are hematopoietic cells of the immune system that are involved in protecting the body against both infectious diseases and foreign materials. The abnormal development and uncontrolled proliferation of these cells can lead to devastating cancers. Their timely recognition in the peripheral blood is critical to diagnosis and treatment. In this study, we developed a microscopic imaging system for improving the visualization of white blood cells on Wright's stained blood smear slides, with two different setups: polarized light imaging and polarized hyperspectral imaging. Based on the polarized light imaging setup, we collected the RGB images of Stokes vector parameters (S0, S1, S2, and S3) of five types of white blood cells (neutrophil, eosinophil, basophil, lymphocyte, and monocyte), and calculated the Stokes vector derived parameters: the degree of polarization (DOP), the degree of linear polarization (DOLP), and the degree of circular polarization (DOCP)). We also calculated Stokes vector data based on the polarized hyperspectral imaging setup. The preliminary results demonstrate that Stokes vector derived parameters (DOP, DOLP, and DOCP) could improve the visualization of granules in granulocytes (neutrophils, eosinophils, and basophils). Furthermore, Stokes vector derived parameters (DOP, DOLP, and DOCP) could improve the visualization of surface structures (protein patterns) of lymphocytes enabling subclassification of lymphocyte subpopulations. Finally, S2, S3, and DOCP could enhance the morphologic visualization of monocyte nucleus. We also demonstrated that the polarized hyperspectral imaging setup could provide complementary spectral information to the spatial information on different Stokes vector parameters of white blood cells. This work demonstrates that polarized light imaging & polarized hyperspectral imaging has the potential to become a strong imaging tool in the diagnosis of disorders arising from white blood cells.
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Affiliation(s)
- Ximing Zhou
- Center for Imaging and Surgical Innovation, The University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX
| | - Hasan K. Mubarak
- Center for Imaging and Surgical Innovation, The University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX
| | - Ling Ma
- Center for Imaging and Surgical Innovation, The University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX
| | - Doreen Palsgrove
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX
| | - Samuel Ortega
- Institute for Applied Microelectronics, University of Las Palmas de Gran Canaria, Canary Islands, Spain
- Norwegian Institute of Food Fisheries and Aquaculture Research, Tromsø, Norway
| | - Gustavo Marrero Callicó
- Institute for Applied Microelectronics, University of Las Palmas de Gran Canaria, Canary Islands, Spain
| | - Edward A Medina
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX
| | - Bradley B Brimhall
- Department of Pathology and Laboratory Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX
| | - Marisa Whitted
- Norwegian Institute of Food Fisheries and Aquaculture Research, Tromsø, Norway
| | - Baowei Fei
- Center for Imaging and Surgical Innovation, The University of Texas at Dallas, Richardson, TX
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX
- University of Texas Southwestern Medical Center, Department of Radiology, Dallas, TX
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5
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Sajman J, Sherman E. High- and Super-Resolution Imaging of Cell-Cell Interfaces. Methods Mol Biol 2023; 2654:149-158. [PMID: 37106181 DOI: 10.1007/978-1-0716-3135-5_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Physical interfaces mediate interactions between multiple types of cells. Despite the importance of such interfaces to the cells' function, their high-resolution optical imaging has been typically limited due to poor alignment of the interfaces relative to the optical plane of imaging. Here, we present a simple and robust method to align cell-cell interfaces in parallel to the coverslip by adhering the interacting cells to two opposing coverslips and bringing them into contact in a controlled and stable fashion. We demonstrate aberration-free high-resolution imaging of interfaces between live T cells and antigen-presenting cells, known as immune synapses, as an outstanding example. Imaging methods may include multiple diffraction-limited and super-resolution microscopy techniques (e.g., bright-field, confocal, STED, and dSTORM). Thus, our simple and widely compatible approach allows imaging with high- and super-resolution the intricate structure and molecular organization within a variety of cell-cell interfaces.
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Affiliation(s)
- Julia Sajman
- Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
- Jerusalem College of technology, Jerusalem, Israel
| | - Eilon Sherman
- Racah Institute of Physics, The Hebrew University, Jerusalem, Israel.
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6
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A roadmap for translational cancer glycoimmunology at single cell resolution. J Exp Clin Cancer Res 2022; 41:143. [PMID: 35428302 PMCID: PMC9013178 DOI: 10.1186/s13046-022-02335-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 03/17/2022] [Indexed: 11/11/2022] Open
Abstract
Cancer cells can evade immune responses by exploiting inhibitory immune checkpoints. Immune checkpoint inhibitor (ICI) therapies based on anti-CTLA-4 and anti-PD-1/PD-L1 antibodies have been extensively explored over the recent years to unleash otherwise compromised anti-cancer immune responses. However, it is also well established that immune suppression is a multifactorial process involving an intricate crosstalk between cancer cells and the immune systems. The cancer glycome is emerging as a relevant source of immune checkpoints governing immunosuppressive behaviour in immune cells, paving an avenue for novel immunotherapeutic options. This review addresses the current state-of-the-art concerning the role played by glycans controlling innate and adaptive immune responses, while shedding light on available experimental models for glycoimmunology. We also emphasize the tremendous progress observed in the development of humanized models for immunology, the paramount contribution of advances in high-throughput single-cell analysis in this context, and the importance of including predictive machine learning algorithms in translational research. This may constitute an important roadmap for glycoimmunology, supporting careful adoption of models foreseeing clinical translation of fundamental glycobiology knowledge towards next generation immunotherapies.
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7
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Disc Large Homolog 1 Is Critical for Early T Cell Receptor Micro Cluster Formation and Activation in Human T Cells. Vaccines (Basel) 2021; 9:vaccines9121446. [PMID: 34960191 PMCID: PMC8709471 DOI: 10.3390/vaccines9121446] [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: 10/19/2021] [Revised: 11/29/2021] [Accepted: 11/30/2021] [Indexed: 11/17/2022] Open
Abstract
T cell activation by antigen involves multiple sequential steps, including T cell receptor-microcluster TCR-(MC) formation, immunological synapse formation, and phosphorylation of mediators downstream of the TCR. The adaptor protein, Disc Large Homolog 1 (DLG1), is known to regulate proximal TCR signaling and, in turn, T cell activation, acting as a molecular chaperone that organizes specific kinases downstream of antigen recognition. In this study, we used knockdown and knockout technologies in human primary T cells and a human T cell line to demonstrate the role of DLG1 in proximal T cell signaling. High-end confocal microscopy was used for pictorial representation of T cell micro-clusters and colocalization studies. From all these studies, we could demonstrate that DLG1 functions even earlier than immunological synapse formation, to regulate T cell activation by promoting TCR-MC formation. Moreover, we found that DLG1 can act as a bridge between the TCR-ζ chain and ZAP70 while inhibiting binding of the phosphatase SHP1 to TCR-ζ. Together, these effects drive dysregulation of T cell activation in DLG1-deficient T cells. Overall, the activation and survival status of T cell is a critical determinant of effective vaccine response, and DLG1-mediated T cell signaling events can be a driving factor for improving vaccine-designing strategies.
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8
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Velas L, Brameshuber M, Huppa JB, Kurz E, Dustin ML, Zelger P, Jesacher A, Schütz GJ. Three-Dimensional Single Molecule Localization Microscopy Reveals the Topography of the Immunological Synapse at Isotropic Precision below 15 nm. NANO LETTERS 2021; 21:9247-9255. [PMID: 34709845 PMCID: PMC8587899 DOI: 10.1021/acs.nanolett.1c03160] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
T-cells engage with antigen-presenting cells in search for antigenic peptides and form transient interfaces termed immunological synapses. Synapse topography affects receptor binding rates and the mutual segregation of proteins due to size exclusion effects. It is hence important to determine the 3D topography of the immunological synapse at high precision. Current methods provide only rather coarse images of the protein distribution within the synapse. Here, we applied supercritical angle fluorescence microscopy combined with defocused imaging, which allows three-dimensional single molecule localization microscopy (3D-SMLM) at an isotropic localization precision below 15 nm. Experiments were performed on hybrid synapses between primary T-cells and functionalized glass-supported lipid bilayers. We used 3D-SMLM to quantify the cleft size within the synapse by mapping the position of the T-cell receptor (TCR) with respect to the supported lipid bilayer, yielding average distances of 18 nm up to 31 nm for activating and nonactivating bilayers, respectively.
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Affiliation(s)
- Lukas Velas
- Institute
of Applied Physics, TU Wien, 1040 Vienna, Austria
| | | | - Johannes B. Huppa
- Institute
for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology
and Immunology, Medical University of Vienna, 1090 Vienna, Austria
| | - Elke Kurz
- Kennedy
Institute of Rheumatology, University of
Oxford, OX3 7FY Oxford, United Kingdom
| | - Michael L. Dustin
- Kennedy
Institute of Rheumatology, University of
Oxford, OX3 7FY Oxford, United Kingdom
| | - Philipp Zelger
- Division
for Biomedical Physics, Medical University
of Innsbruck, 6020 Innsbruck, Austria
| | - Alexander Jesacher
- Division
for Biomedical Physics, Medical University
of Innsbruck, 6020 Innsbruck, Austria
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9
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Wohl I, Sherman E. Spectral Analysis of ATP-Dependent Mechanical Vibrations in T Cells. Front Cell Dev Biol 2021; 9:590655. [PMID: 34178972 PMCID: PMC8222795 DOI: 10.3389/fcell.2021.590655] [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: 08/02/2020] [Accepted: 04/27/2021] [Indexed: 11/13/2022] Open
Abstract
Mechanical vibrations affect multiple cell properties, including its diffusivity, entropy, internal content organization, and thus-function. Here, we used Differential Interference Contrast (DIC), confocal, and Total Internal Reflection Fluorescence (TIRF) microscopies to study mechanical vibrations in live (Jurkat) T cells. Vibrations were measured via the motion of intracellular particles and plasma membrane. These vibrations depend on adenosine triphosphate (ATP) consumption and on Myosin II activity. We then used spectral analysis of these vibrations to distinguish the effects of thermal agitation, ATP-dependent mechanical work and cytoskeletal visco-elasticity. Parameters of spectral analyses could be related to mean square displacement (MSD) analyses with specific advantages in characterizing intracellular mechanical work. We identified two spectral ranges where mechanical work dominated vibrations of intracellular components: 0-3 Hz for intracellular particles and the plasma-membrane, and 100-150 Hz for the plasma-membrane. The 0-3 Hz vibrations of the cell membrane that we measured in an experimental model of immune synapse (IS) are expected to affect the IS formation and function in effector cells. It may also facilitate immunological escape of extensively vibrating malignant cells.
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Affiliation(s)
| | - Eilon Sherman
- Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
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10
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Lemaître F, Carmena Moratalla A, Farzam-Kia N, Carpentier Solorio Y, Tastet O, Cleret-Buhot A, Guimond JV, Haddad E, Arbour N. Capturing T Lymphocytes' Dynamic Interactions With Human Neural Cells Using Time-Lapse Microscopy. Front Immunol 2021; 12:668483. [PMID: 33968073 PMCID: PMC8100528 DOI: 10.3389/fimmu.2021.668483] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 03/29/2021] [Indexed: 11/17/2022] Open
Abstract
To fully perform their functions, T lymphocytes migrate within organs’ parenchyma and interact with local cells. Infiltration of T lymphocytes within the central nervous system (CNS) is associated with numerous neurodegenerative disorders. Nevertheless, how these immune cells communicate and respond to neural cells remains unresolved. To investigate the behavior of T lymphocytes that reach the CNS, we have established an in vitro co-culture model and analyzed the spatiotemporal interactions between human activated CD8+ T lymphocytes and primary human astrocytes and neurons using time-lapse microscopy. By combining multiple variables extracted from individual CD8+ T cell tracking, we show that CD8+ T lymphocytes adopt a more motile and exploratory behavior upon interacting with astrocytes than with neurons. Pretreatment of astrocytes or neurons with IL-1β to mimic in vivo inflammation significantly increases CD8+ T lymphocyte motility. Using visual interpretation and analysis of numerical variables extracted from CD8+ T cell tracking, we identified four distinct CD8+ T lymphocyte behaviors: scanning, dancing, poking and round. IL-1β-pretreatment significantly increases the proportion of scanning CD8+ T lymphocytes, which are characterized by active exploration, and reduces the proportion of round CD8+ T lymphocytes, which are less active. Blocking MHC class I on astrocytes significantly diminishes the proportion of poking CD8+ T lymphocytes, which exhibit synapse-like interactions. Lastly, our co-culture time-lapse model is easily adaptable and sufficiently sensitive and powerful to characterize and quantify spatiotemporal interactions between human T lymphocytes and primary human cells in different conditions while preserving viability of fragile cells such as neurons and astrocytes.
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Affiliation(s)
- Florent Lemaître
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.,Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Ana Carmena Moratalla
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.,Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Negar Farzam-Kia
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.,Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Yves Carpentier Solorio
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.,Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Olivier Tastet
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Aurélie Cleret-Buhot
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
| | - Jean Victor Guimond
- Centre Local de Services Communautaires des Faubourgs, Centre Intégré Universitaire en Santé et Services Sociaux du Centre-Sud-de-l'Ile-de-Montréal, Montréal, QC, Canada
| | - Elie Haddad
- Centre de Recherche du Centre Hospitalier Universitaire Sainte-Justine (CHU Sainte-Justine), Department of Microbiology, Infectious Diseases, and Immunology and Department of Pediatrics, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada
| | - Nathalie Arbour
- Department of Neurosciences, Faculty of Medicine, Université de Montréal, Montreal, QC, Canada.,Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montreal, QC, Canada
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11
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Sajman J, Razvag Y, Schidorsky S, Kinrot S, Hermon K, Yakovian O, Sherman E. Adhering interacting cells to two opposing coverslips allows super-resolution imaging of cell-cell interfaces. Commun Biol 2021; 4:439. [PMID: 33795833 PMCID: PMC8016881 DOI: 10.1038/s42003-021-01960-2] [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: 12/16/2019] [Accepted: 03/03/2021] [Indexed: 02/01/2023] Open
Abstract
Cell-cell interfaces convey mechanical and chemical information in multicellular systems. Microscopy has revealed intricate structure of such interfaces, yet typically with limited resolution due to diffraction and unfavourable orthogonal orientation of the interface to the coverslip. We present a simple and robust way to align cell-cell interfaces in parallel to the coverslip by adhering the interacting cells to two opposing coverslips. We demonstrate high-quality diffraction-limited and super-resolution imaging of interfaces (immune-synapses) between fixed and live CD8+ T-cells and either antigen presenting cells or melanoma cells. Imaging methods include bright-field, confocal, STED, dSTORM, SOFI, SRRF and large-scale tiled images. The low background, lack of aberrations and enhanced spatial stability of our method relative to existing cell-trapping techniques allow use of these methods. We expect that the simplicity and wide-compatibility of our approach will allow its wide dissemination for super-resolving the intricate structure and molecular organization in a variety of cell-cell interfaces.
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Affiliation(s)
- Julia Sajman
- grid.9619.70000 0004 1937 0538Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
| | - Yair Razvag
- grid.9619.70000 0004 1937 0538Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
| | - Shachar Schidorsky
- grid.9619.70000 0004 1937 0538Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
| | - Seon Kinrot
- grid.9619.70000 0004 1937 0538Racah Institute of Physics, The Hebrew University, Jerusalem, Israel ,grid.38142.3c000000041936754XPresent Address: Graduate Program in Biophysics, Howard Hughes Medical Institute, Department of Chemistry and Chemical Biology, Department of Physics, Harvard University, Cambridge, MA USA
| | - Kobi Hermon
- grid.9619.70000 0004 1937 0538Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
| | - Oren Yakovian
- grid.9619.70000 0004 1937 0538Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
| | - Eilon Sherman
- grid.9619.70000 0004 1937 0538Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
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12
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Jing H, Pálmai M, Saed B, George A, Snee PT, Hu YS. Cytosolic delivery of membrane-penetrating QDs into T cell lymphocytes: implications in immunotherapy and drug delivery. NANOSCALE 2021; 13:5519-5529. [PMID: 33688882 PMCID: PMC8029070 DOI: 10.1039/d0nr08362c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
We report single-particle characterization of membrane-penetrating semiconductor quantum dots (QDs) in T cell lymphocytes. We functionalized water-soluble CdSe/CdZnS QDs with a cell-penetrating peptide composed of an Asp-Ser-Ser (DSS) repeat sequence. DSS and peptide-free control QDs displayed concentration-dependent internalization. Intensity profiles from single-particle imaging revealed a propensity of DSS-QDs to maintain a monomeric state in the T cell cytosol, whereas control QDs formed pronounced clusters. Single-particle tracking showed a direct correlation between individual QD clusters' mobility and aggregation state. A significant portion of control QDs colocalized with an endosome marker inside the T cells, while the percentage of DSS-QDs colocalized dropped to 9%. Endocytosis inhibition abrogated the internalization of control QDs, while DSS-QD internalization only mildly decreased, suggesting an alternative cell-entry mechanism. Using 3D single-particle tracking, we captured the rapid membrane-penetrating activity of a DSS-QD. The ability to characterize membrane penetrating activities in live T cells creates inroads for the optimization of gene therapy and drug delivery through the use of novel nanomaterials.
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Affiliation(s)
- Haoran Jing
- Department of Chemistry, College of Liberal Arts and Sciences, University of Illinois at Chicago, Chicago, IL 60607-7061, USA.
| | - Marcell Pálmai
- Department of Chemistry, College of Liberal Arts and Sciences, University of Illinois at Chicago, Chicago, IL 60607-7061, USA.
| | - Badeia Saed
- Department of Chemistry, College of Liberal Arts and Sciences, University of Illinois at Chicago, Chicago, IL 60607-7061, USA.
| | - Anne George
- Department of Oral Biology, College of Dentistry, University of Illinois at Chicago, Chicago, IL 60612-7211, USA
| | - Preston T Snee
- Department of Chemistry, College of Liberal Arts and Sciences, University of Illinois at Chicago, Chicago, IL 60607-7061, USA.
| | - Ying S Hu
- Department of Chemistry, College of Liberal Arts and Sciences, University of Illinois at Chicago, Chicago, IL 60607-7061, USA.
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13
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Lee M, Lee YH, Song J, Kim G, Jo Y, Min H, Kim CH, Park Y. Deep-learning-based three-dimensional label-free tracking and analysis of immunological synapses of CAR-T cells. eLife 2020; 9:49023. [PMID: 33331817 PMCID: PMC7817186 DOI: 10.7554/elife.49023] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 12/16/2020] [Indexed: 12/14/2022] Open
Abstract
The immunological synapse (IS) is a cell-cell junction between a T cell and a professional antigen-presenting cell. Since the IS formation is a critical step for the initiation of an antigen-specific immune response, various live-cell imaging techniques, most of which rely on fluorescence microscopy, have been used to study the dynamics of IS. However, the inherent limitations associated with the fluorescence-based imaging, such as photo-bleaching and photo-toxicity, prevent the long-term assessment of dynamic changes of IS with high frequency. Here, we propose and experimentally validate a label-free, volumetric, and automated assessment method for IS dynamics using a combinational approach of optical diffraction tomography and deep learning-based segmentation. The proposed method enables an automatic and quantitative spatiotemporal analysis of IS kinetics of morphological and biochemical parameters associated with IS dynamics, providing a new option for immunological research.
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Affiliation(s)
- Moosung Lee
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Daejeon, Republic of Korea
| | - Young-Ho Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea.,Curocell Inc, Daejeon, Republic of Korea
| | - Jinyeop Song
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Daejeon, Republic of Korea
| | - Geon Kim
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Daejeon, Republic of Korea
| | - YoungJu Jo
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Daejeon, Republic of Korea
| | | | - Chan Hyuk Kim
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, Daejeon, Republic of Korea
| | - YongKeun Park
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.,KAIST Institute for Health Science and Technology, Daejeon, Republic of Korea
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14
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Zhang X, Mariano CF, Ando Y, Shen K. Bioengineering tools for probing intracellular events in T lymphocytes. WIREs Mech Dis 2020; 13:e1510. [PMID: 33073545 DOI: 10.1002/wsbm.1510] [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: 07/16/2020] [Revised: 09/14/2020] [Accepted: 09/16/2020] [Indexed: 11/11/2022]
Abstract
T lymphocytes are the central coordinator and executor of many immune functions. The activation and function of T lymphocytes are mediated through the engagement of cell surface receptors and regulated by a myriad of intracellular signaling network. Bioengineering tools, including imaging modalities and fluorescent probes, have been developed and employed to elucidate the cellular events throughout the functional lifespan of T cells. A better understanding of these events can broaden our knowledge in the immune systems biology, as well as accelerate the development of effective diagnostics and immunotherapies. Here we review the commonly used and recently developed techniques and probes for monitoring T lymphocyte intracellular events, following the order of intracellular events in T cells from activation, signaling, metabolism to apoptosis. The techniques introduced here can be broadly applied to other immune cells and cell systems. This article is categorized under: Immune System Diseases > Molecular and Cellular Physiology Immune System Diseases > Biomedical Engineering Infectious Diseases > Biomedical Engineering.
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Affiliation(s)
- Xinyuan Zhang
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Chelsea F Mariano
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Yuta Ando
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA
| | - Keyue Shen
- Department of Biomedical Engineering, University of Southern California, Los Angeles, California, USA.,Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California, USA.,USC Stem Cell, University of Southern California, Los Angeles, California, USA
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15
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Biolato AM, Filali L, Wurzer H, Hoffmann C, Gargiulo E, Valitutti S, Thomas C. Actin remodeling and vesicular trafficking at the tumor cell side of the immunological synapse direct evasion from cytotoxic lymphocytes. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 356:99-130. [PMID: 33066877 DOI: 10.1016/bs.ircmb.2020.07.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Andrea Michela Biolato
- Cytoskeleton and Cancer Progression, Department of Oncology, Luxembourg Institute of Health, Luxembourg City, Luxembourg; Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Liza Filali
- Cancer Research Center of Toulouse, INSERM, Toulouse, France
| | - Hannah Wurzer
- Cytoskeleton and Cancer Progression, Department of Oncology, Luxembourg Institute of Health, Luxembourg City, Luxembourg; Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Céline Hoffmann
- Cytoskeleton and Cancer Progression, Department of Oncology, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Ernesto Gargiulo
- Tumor-Stroma Interactions, Department of Oncology, Luxembourg Institute of Health, Luxembourg City, Luxembourg
| | - Salvatore Valitutti
- Cancer Research Center of Toulouse, INSERM, Toulouse, France; Department of Pathology, Institut Universitaire du Cancer-Oncopole, Toulouse, France.
| | - Clément Thomas
- Cytoskeleton and Cancer Progression, Department of Oncology, Luxembourg Institute of Health, Luxembourg City, Luxembourg.
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16
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Murin CD. Considerations of Antibody Geometric Constraints on NK Cell Antibody Dependent Cellular Cytotoxicity. Front Immunol 2020; 11:1635. [PMID: 32849559 PMCID: PMC7406664 DOI: 10.3389/fimmu.2020.01635] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 06/18/2020] [Indexed: 12/31/2022] Open
Abstract
It has been well-established that antibody isotype, glycosylation, and epitope all play roles in the process of antibody dependent cellular cytotoxicity (ADCC). For natural killer (NK) cells, these phenotypes are linked to cellular activation through interaction with the IgG receptor FcγRIIIa, a single pass transmembrane receptor that participates in cytoplasmic signaling complexes. Therefore, it has been hypothesized that there may be underlying spatial and geometric principles that guide proper assembly of an activation complex within the NK cell immune synapse. Further, synergy of antibody phenotypic properties as well as allosteric changes upon antigen binding may also play an as-of-yet unknown role in ADCC. Understanding these facets, however, remains hampered by difficulties associated with studying immune synapse dynamics using classical approaches. In this review, I will discuss relevant NK cell biology related to ADCC, including the structural biology of Fc gamma receptors, and how the dynamics of the NK cell immune synapse are being studied using innovative microscopy techniques. I will provide examples from the literature demonstrating the effects of spatial and geometric constraints on the T cell receptor complex and how this relates to intracellular signaling and the molecular nature of lymphocyte activation complexes, including those of NK cells. Finally, I will examine how the integration of high-throughput and "omics" technologies will influence basic NK cell biology research moving forward. Overall, the goal of this review is to lay a basis for understanding the development of drugs and therapeutic antibodies aimed at augmenting appropriate NK cell ADCC activity in patients being treated for a wide range of illnesses.
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Affiliation(s)
- Charles D. Murin
- Department of Integrative Structural and Computational Biology, Scripps Research, La Jolla, CA, United States
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17
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Tamzalit F, Wang MS, Jin W, Tello-Lafoz M, Boyko V, Heddleston JM, Black CT, Kam LC, Huse M. Interfacial actin protrusions mechanically enhance killing by cytotoxic T cells. Sci Immunol 2020; 4:4/33/eaav5445. [PMID: 30902904 DOI: 10.1126/sciimmunol.aav5445] [Citation(s) in RCA: 81] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 02/05/2019] [Indexed: 12/30/2022]
Abstract
Cytotoxic T lymphocytes (CTLs) kill by forming immunological synapses with target cells and secreting toxic proteases and the pore-forming protein perforin into the intercellular space. Immunological synapses are highly dynamic structures that boost perforin activity by applying mechanical force against the target cell. Here, we used high-resolution imaging and microfabrication to investigate how CTLs exert synaptic forces and coordinate their mechanical output with perforin secretion. Using micropatterned stimulatory substrates that enable synapse growth in three dimensions, we found that perforin release occurs at the base of actin-rich protrusions that extend from central and intermediate locations within the synapse. These protrusions, which depended on the cytoskeletal regulator WASP and the Arp2/3 actin nucleation complex, were required for synaptic force exertion and efficient killing. They also mediated physical deformation of the target cell surface during CTL-target cell interactions. Our results reveal the mechanical basis of cellular cytotoxicity and highlight the functional importance of dynamic, three-dimensional architecture in immune cell-cell interfaces.
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Affiliation(s)
- Fella Tamzalit
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Mitchell S Wang
- Pharmacology Graduate Program, Weill Cornell Medical College, New York, NY, USA
| | - Weiyang Jin
- Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - Maria Tello-Lafoz
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Vitaly Boyko
- Molecular Cytology Core Facility, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - John M Heddleston
- Advanced Imaging Center, Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Charles T Black
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, USA
| | - Lance C Kam
- Department of Biomedical Engineering, Columbia University, New York, NY, USA
| | - Morgan Huse
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
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18
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Abstract
Advances in academic and clinical studies during the last several years have resulted in practical outcomes in adoptive immune therapy of cancer. Immune cells can be programmed with molecular modules that increase their therapeutic potency and specificity. It has become obvious that successful immunotherapy must take into account the full complexity of the immune system and, when possible, include the use of multifactor cell reprogramming that allows fast adjustment during the treatment. Today, practically all immune cells can be stably or transiently reprogrammed against cancer. Here, we review works related to T cell reprogramming, as the most developed field in immunotherapy. We discuss factors that determine the specific roles of αβ and γδ T cells in the immune system and the structure and function of T cell receptors in relation to other structures involved in T cell target recognition and immune response. We also discuss the aspects of T cell engineering, specifically the construction of synthetic T cell receptors (synTCRs) and chimeric antigen receptors (CARs) and the use of engineered T cells in integrative multifactor therapy of cancer.
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Affiliation(s)
- Samuel G Katz
- Department of Pathology, Yale School of Medicine, New Haven, CT, USA
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19
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Rapid Morphological and Cytoskeletal Response to Microgravity in Human Primary Macrophages. Int J Mol Sci 2019; 20:ijms20102402. [PMID: 31096581 PMCID: PMC6567851 DOI: 10.3390/ijms20102402] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 04/30/2019] [Accepted: 05/14/2019] [Indexed: 01/14/2023] Open
Abstract
The FLUMIAS (Fluorescence-Microscopic Analyses System for Life-Cell-Imaging in Space) confocal laser spinning disk fluorescence microscope represents a new imaging capability for live cell imaging experiments on suborbital ballistic rocket missions. During the second pioneer mission of this microscope system on the TEXUS-54 suborbital rocket flight, we developed and performed a live imaging experiment with primary human macrophages. We simultaneously imaged four different cellular structures (nucleus, cytoplasm, lysosomes, actin cytoskeleton) by using four different live cell dyes (Nuclear Violet, Calcein, LysoBrite, SiR-actin) and laser wavelengths (405, 488, 561, and 642 nm), and investigated the cellular morphology in microgravity (10−4 to 10−5 g) over a period of about six minutes compared to 1 g controls. For live imaging of the cytoskeleton during spaceflight, we combined confocal laser microscopy with the SiR-actin probe, a fluorogenic silicon-rhodamine (SiR) conjugated jasplakinolide probe that binds to F-actin and displays minimal toxicity. We determined changes in 3D cell volume and surface, nuclear volume and in the actin cytoskeleton, which responded rapidly to the microgravity environment with a significant reduction of SiR-actin fluorescence after 4–19 s microgravity, and adapted subsequently until 126–151 s microgravity. We conclude that microgravity induces geometric cellular changes and rapid response and adaptation of the potential gravity-transducing cytoskeleton in primary human macrophages.
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20
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Campbell-Tofte J, Vrahatis A, Josefsen K, Mehlsen J, Winther K. Investigating the aetiology of adverse events following HPV vaccination with systems vaccinology. Cell Mol Life Sci 2019; 76:67-87. [PMID: 30324425 PMCID: PMC11105185 DOI: 10.1007/s00018-018-2925-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 09/10/2018] [Accepted: 09/20/2018] [Indexed: 12/18/2022]
Abstract
In contrast to the insidious and poorly immunogenic human papillomavirus (HPV) infections, vaccination with the HPV virus-like particles (vlps) is non-infectious and stimulates a strong neutralizing-antibody response that protects HPV-naïve vaccinees from viral infection and associated cancers. However, controversy about alleged adverse events following immunization (AEFI) with the vlps have led to extensive reductions in vaccine acceptance, with countries like Japan dropping it altogether. The AEFIs are grouped into chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). In this review, we present a hypothesis that the AEFIs might arise from malfunctions within the immune system when confronted with the unusual antigen. In addition, we outline how the pathophysiology of the AEFIs can be cost-effectively investigated with the holistic principles of systems vaccinology in a two-step process. First, comprehensive immunological profiles of HPV vaccinees exhibiting the AEFIs are generated by integrating the data derived from serological profiling for prominent HPV antibodies and serum cytokines, with data from serum metabolomics, peripheral white blood cells transcriptomics and gut microbiome profiling. Next, the immunological profiles are compared with corresponding profiles generated for matched (a) HPV vaccinees without AEFIs; (b) non-HPV-vaccinated individuals with CFS/ME-like symptoms; and (c) non-HPV-vaccinated individuals without CFS/ME. In these comparisons, any causal links between HPV vaccine and the AEFIs, as well as the underlying molecular basis for the links will be revealed. Such a study should provide an objective basis for evaluating HPV vaccine safety and for identifying biomarkers for individuals at risk of developing AEFI with HPV vaccination.
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Affiliation(s)
| | | | - Knud Josefsen
- Bartholin Institute, Rigshospitalet, Blegdamsvej 9, 2100, Copenhagen Ø, Denmark
| | - Jesper Mehlsen
- Coordinating Research Centre, Bispebjerg and Frederiksberg Hospital, Nordre Fasanvej 57, 2000, Frederiksberg, Denmark
| | - Kaj Winther
- Department of Nutrition, Exercise and Sports, University of Copenhagen, Nørre Allé 51, DK-2200, Copenhagen N, Denmark
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21
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Neve-Oz Y, Sajman J, Razvag Y, Sherman E. InterCells: A Generic Monte-Carlo Simulation of Intercellular Interfaces Captures Nanoscale Patterning at the Immune Synapse. Front Immunol 2018; 9:2051. [PMID: 30254635 PMCID: PMC6141710 DOI: 10.3389/fimmu.2018.02051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 08/20/2018] [Indexed: 12/03/2022] Open
Abstract
Molecular interactions across intercellular interfaces serve to convey information between cells and to trigger appropriate cell functions. Examples include cell development and growth in tissues, neuronal and immune synapses (ISs). Here, we introduce an agent-based Monte-Carlo simulation of user-defined cellular interfaces. The simulation allows for membrane molecules, embedded at intercellular contacts, to diffuse and interact, while capturing the topography and energetics of the plasma membranes of the interface. We provide a detailed example related to pattern formation in the early IS. Using simulation predictions and three-color single molecule localization microscopy (SMLM), we detected the intricate mutual patterning of T cell antigen receptors (TCRs), integrins and glycoproteins in early T cell contacts with stimulating coverslips. The simulation further captures the dynamics of the patterning under the experimental conditions and at the IS with antigen presenting cells (APCs). Thus, we provide a generic tool for simulating realistic cell-cell interfaces, which can be used for critical hypothesis testing and experimental design in an iterative manner.
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Affiliation(s)
- Yair Neve-Oz
- Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
| | - Julia Sajman
- Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
| | - Yair Razvag
- Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
| | - Eilon Sherman
- Racah Institute of Physics, The Hebrew University, Jerusalem, Israel
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22
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Rossboth B, Arnold AM, Ta H, Platzer R, Kellner F, Huppa JB, Brameshuber M, Baumgart F, Schütz GJ. TCRs are randomly distributed on the plasma membrane of resting antigen-experienced T cells. Nat Immunol 2018; 19:821-827. [PMID: 30013143 PMCID: PMC6071872 DOI: 10.1038/s41590-018-0162-7] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 06/14/2018] [Indexed: 12/29/2022]
Abstract
The main function of T cells is to identify harmful antigens as quickly and precisely as possible. Super-resolution microscopy data have indicated that global clustering of T cell antigen receptors (TCRs) occurs before T cell activation. Such pre-activation clustering has been interpreted as representing a potential regulatory mechanism that fine tunes the T cell response. We found here that apparent TCR nanoclustering could be attributed to overcounting artifacts inherent to single-molecule-localization microscopy. Using complementary super-resolution approaches and statistical image analysis, we found no indication of global nanoclustering of TCRs on antigen-experienced CD4+ T cells under non-activating conditions. We also used extensive simulations of super-resolution images to provide quantitative limits for the degree of randomness of the TCR distribution. Together our results suggest that the distribution of TCRs on the plasma membrane is optimized for fast recognition of antigen in the first phase of T cell activation.
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Affiliation(s)
| | | | - Haisen Ta
- Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - René Platzer
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Florian Kellner
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Johannes B Huppa
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
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23
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Gp41 dynamically interacts with the TCR in the immune synapse and promotes early T cell activation. Sci Rep 2018; 8:9747. [PMID: 29950577 PMCID: PMC6021400 DOI: 10.1038/s41598-018-28114-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 06/14/2018] [Indexed: 12/21/2022] Open
Abstract
The HIV-1 glycoprotein gp41 critically mediates CD4+ T-cell infection by HIV-1 during viral entry, assembly, and release. Although multiple immune-regulatory activities of gp41 have been reported, the underlying mechanisms of these activities remain poorly understood. Here we employed multi-colour single molecule localization microscopy (SMLM) to resolve interactions of gp41 proteins with cellular proteins at the plasma membrane (PM) of fixed and live CD4+ T-cells with resolution of ~20–30 nm. We observed that gp41 clusters dynamically associated with the T cell antigen receptor (TCR) at the immune synapse upon TCR stimulation. This interaction, confirmed by FRET, depended on the virus clone, was reduced by the gp41 ectodomain in tight contacts, and was completely abrogated by mutation of the gp41 transmembrane domain. Strikingly, gp41 preferentially colocalized with phosphorylated TCRs at the PM of activated T-cells and promoted TCR phosphorylation. Gp41 expression also resulted in enhanced CD69 upregulation, and in massive cell death after 24–48 hrs. Our results shed new light on HIV-1 assembly mechanisms at the PM of host T-cells and its impact on TCR stimulation.
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24
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Nanoscale kinetic segregation of TCR and CD45 in engaged microvilli facilitates early T cell activation. Nat Commun 2018; 9:732. [PMID: 29467364 PMCID: PMC5821895 DOI: 10.1038/s41467-018-03127-w] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 01/18/2018] [Indexed: 11/08/2022] Open
Abstract
T cells have a central function in mounting immune responses. However, mechanisms of their early activation by cognate antigens remain incompletely understood. Here we use live-cell multi-colour single-molecule localization microscopy to study the dynamic separation between TCRs and CD45 glycoprotein phosphatases in early cell contacts under TCR-activating and non-activating conditions. Using atomic force microscopy, we identify these cell contacts with engaged microvilli and characterize their morphology, rigidity and dynamics. Physical modelling and simulations of the imaged cell interfaces quantitatively capture the TCR-CD45 separation. Surprisingly, TCR phosphorylation negatively correlates with TCR-CD45 separation. These data support a refined kinetic-segregation model. First, kinetic-segregation occurs within seconds from TCR activation in engaged microvilli. Second, TCRs should be segregated, yet not removed too far, from CD45 for their optimal and localized activation within clusters. Our combined imaging and computational approach prove an important tool in the study of dynamic protein organization in cell interfaces.
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25
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Šuštar V, Vainio M, Mattila PK. Visualization and Quantitative Analysis of the Actin Cytoskeleton Upon B Cell Activation. Methods Mol Biol 2018; 1707:243-257. [PMID: 29388113 DOI: 10.1007/978-1-4939-7474-0_18] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The formation of the immunological synapse upon B cell activation critically depends on the rearrangement of the submembranous actin cytoskeleton. Polymerization of actin monomers into filaments provides the force required for B cell spreading on the antigen-presenting cell (APC). Interestingly, the actin network also participates in cellular signaling at multiple levels. Fluorescence microscopy plays a critical role in furthering our understanding of the various functions of the cytoskeleton, and has become an important tool in the studies on B cell activation. The actin cytoskeleton can be tracked in live cells with various fluorescent probes binding to actin, or in fixed cells typically with phalloidin staining. Here, we present the usage of TIRF microscopy and an image analysis workflow for studying the overall density and organization of the actin network upon B cell spreading on antigen-coated glass, a widely used model system for the formation of the immunological synapse.
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Affiliation(s)
- Vid Šuštar
- Institute of Biomedicine, Unit of Pathology, and MediCity Research Laboratories, University of Turku, Turku, Finland
| | - Marika Vainio
- Institute of Biomedicine, Unit of Pathology, and MediCity Research Laboratories, University of Turku, Turku, Finland
| | - Pieta K Mattila
- Institute of Biomedicine, Unit of Pathology, and MediCity Research Laboratories, University of Turku, Turku, Finland.
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26
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Abstract
T cell receptors (TCRs) are protein complexes formed by six different polypeptides. In most T cells, TCRs are composed of αβ subunits displaying immunoglobulin-like variable domains that recognize peptide antigens associated with major histocompatibility complex molecules expressed on the surface of antigen-presenting cells. TCRαβ subunits are associated with the CD3 complex formed by the γ, δ, ε, and ζ subunits, which are invariable and ensure signal transduction. Here, we review how the expression and function of TCR complexes are orchestrated by several fine-tuned cellular processes that encompass (a) synthesis of the subunits and their correct assembly and expression at the plasma membrane as a single functional complex, (b) TCR membrane localization and dynamics at the plasma membrane and in endosomal compartments, (c) TCR signal transduction leading to T cell activation, and (d) TCR degradation. These processes balance each other to ensure efficient T cell responses to a variety of antigenic stimuli while preventing autoimmunity.
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Affiliation(s)
- Andrés Alcover
- Lymphocyte Cell Biology Unit, INSERM U1221, Department of Immunology, Institut Pasteur, Paris 75015, France; ,
| | - Balbino Alarcón
- Severo Ochoa Center for Molecular Biology, CSIC-UAM, Madrid 28049, Spain;
| | - Vincenzo Di Bartolo
- Lymphocyte Cell Biology Unit, INSERM U1221, Department of Immunology, Institut Pasteur, Paris 75015, France; ,
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27
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Limitations of Qdot labelling compared to directly-conjugated probes for single particle tracking of B cell receptor mobility. Sci Rep 2017; 7:11379. [PMID: 28900238 PMCID: PMC5595841 DOI: 10.1038/s41598-017-11563-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 08/18/2017] [Indexed: 12/25/2022] Open
Abstract
Single-particle tracking (SPT) is a powerful method for exploring single-molecule dynamics in living cells with nanoscale spatiotemporal resolution. Photostability and bright fluorescence make quantum dots (Qdots) a popular choice for SPT. However, their large size could potentially alter the mobility of the molecule of interest. To test this, we labelled B cell receptors on the surface of B-lymphocytes with monovalent Fab fragments of antibodies that were either linked to Qdots via streptavidin or directly conjugated to the small organic fluorophore Cy3. Imaging of receptor mobility by total internal reflection fluorescence microscopy (TIRFM), followed by quantitative single-molecule diffusion and confinement analysis, definitively showed that Qdots sterically hinder lateral mobility regardless of the substrate to which the cells were adhered. Qdot labelling also drastically altered the frequency with which receptors transitioned between apparent slow- and fast-moving states and reduced the size of apparent confinement zones. Although we show that Qdot-labelled probes can detect large differences in receptor mobility, they fail to resolve subtle differences in lateral diffusion that are readily detectable using Cy3-labelled Fabs. Our findings highlight the utility and limitations of using Qdots for TIRFM and wide-field-based SPT, and have significant implications for interpreting SPT data.
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28
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Live-Cell Super-resolution Reveals F-Actin and Plasma Membrane Dynamics at the T Cell Synapse. Biophys J 2017; 112:1703-1713. [PMID: 28445761 DOI: 10.1016/j.bpj.2017.01.038] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 01/29/2023] Open
Abstract
The cortical actin cytoskeleton has been shown to be critical for the reorganization and heterogeneity of plasma membrane components of many cells, including T cells. Building on previous studies at the T cell immunological synapse, we quantitatively assess the structure and dynamics of this meshwork using live-cell superresolution fluorescence microscopy and spatio-temporal image correlation spectroscopy. We show for the first time, to our knowledge, that not only does the dense actin cortex flow in a retrograde fashion toward the synapse center, but the plasma membrane itself shows similar behavior. Furthermore, using two-color, live-cell superresolution cross-correlation spectroscopy, we demonstrate that the two flows are correlated and, in addition, we show that coupling may extend to the outer leaflet of the plasma membrane by examining the flow of GPI-anchored proteins. Finally, we demonstrate that the actin flow is correlated with a third component, α-actinin, which upon CRISPR knockout led to reduced plasma membrane flow directionality despite increased actin flow velocity. We hypothesize that this apparent cytoskeletal-membrane coupling could provide a mechanism for driving the observed retrograde flow of signaling molecules such as the TCR, Lck, ZAP70, LAT, and SLP76.
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29
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30
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Abstract
The plasma membrane is a complex medium where transmembrane proteins diffuse and interact to facilitate cell function. Membrane protein mobility is affected by multiple mechanisms, including crowding, trapping, medium elasticity and structure, thus limiting our ability to distinguish them in intact cells. Here we characterize the mobility and organization of a short transmembrane protein at the plasma membrane of live T cells, using single particle tracking and photoactivated-localization microscopy. Protein mobility is highly heterogeneous, subdiffusive and ergodic-like. Using mobility characteristics, we segment individual trajectories into subpopulations with distinct Gaussian step-size distributions. Particles of low-to-medium mobility consist of clusters, diffusing in a viscoelastic and fractal-like medium and are enriched at the centre of the cell footprint. Particles of high mobility undergo weak confinement and are more evenly distributed. This study presents a methodological approach to resolve simultaneous mixed subdiffusion mechanisms acting on polydispersed samples and complex media such as cell membranes. Membrane protein diffusion is affected by distinct mechanisms such as molecular crowding and medium elasticity. Here the authors present an analytical approach to analyse single particle trajectories and distinguish mixed subdiffusive processes affecting membrane protein mobility in living cells.
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Abstract
T cell signaling is inextricably linked to actin cytoskeletal dynamics at the immunological synapse (IS). This process can be imaged in living T cells expressing GFP actin or fluorescent F-actin binding proteins. Because of its planar nature, the IS provides a unique opportunity to image events as they happen, monitoring changes in actin retrograde flow in T cells interacting with different stimulatory surfaces or after pharmacological treatments. Here, we described the imaging methods and analytical procedures used to measure actin velocity across the IS in T cells spreading on planar stimulatory surfaces.
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Affiliation(s)
- Katarzyna I Jankowska
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, 3615 Civic Center Blvd, ARC 816D, Philadelphia, PA, 19104, USA
- Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, USA
| | - Janis K Burkhardt
- Department of Pathology and Laboratory Medicine, Children's Hospital of Philadelphia Research Institute, 3615 Civic Center Blvd, ARC 816D, Philadelphia, PA, 19104, USA.
- Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, USA.
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32
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Barr VA, Yi J, Samelson LE. Super-resolution Analysis of TCR-Dependent Signaling: Single-Molecule Localization Microscopy. Methods Mol Biol 2017; 1584:183-206. [PMID: 28255704 PMCID: PMC6676910 DOI: 10.1007/978-1-4939-6881-7_13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Single-molecule localization microscopy (SMLM) comprises methods that produce super-resolution images from molecular locations of single molecules. These techniques mathematically determine the center of a diffraction-limited spot produced by a fluorescent molecule, which represents the most likely location of the molecule. Only a small cohort of well-separated molecules is visualized in a single image, and then many images are obtained from a single sample. The localizations from all the images are combined to produce a super-resolution picture of the sample. Here we describe the application of two methods, photoactivation localization microscopy (PALM) and direct stochastic optical reconstruction microscopy (dSTORM), to the study of signaling microclusters in T cells.
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Affiliation(s)
- Valarie A Barr
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892-4256, USA
| | - Jason Yi
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892-4256, USA
| | - Lawrence E Samelson
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD, 20892-4256, USA.
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Balta E, Stopp J, Castelletti L, Kirchgessner H, Samstag Y, Wabnitz GH. Qualitative and quantitative analysis of PMN/T-cell interactions by InFlow and super-resolution microscopy. Methods 2017; 112:25-38. [DOI: 10.1016/j.ymeth.2016.09.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 09/23/2016] [Accepted: 09/27/2016] [Indexed: 10/20/2022] Open
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Barr VA, Sherman E, Yi J, Akpan I, Rouquette-Jazdanian AK, Samelson LE. Development of nanoscale structure in LAT-based signaling complexes. J Cell Sci 2016; 129:4548-4562. [PMID: 27875277 PMCID: PMC5201021 DOI: 10.1242/jcs.194886] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 11/04/2016] [Indexed: 12/30/2022] Open
Abstract
The adapter molecule linker for activation of T cells (LAT) plays a crucial role in forming signaling complexes induced by stimulation of the T cell receptor (TCR). These multi-molecular complexes are dynamic structures that activate highly regulated signaling pathways. Previously, we have demonstrated nanoscale structure in LAT-based complexes where the adapter SLP-76 (also known as LCP2) localizes to the periphery of LAT clusters. In this study, we show that initially LAT and SLP-76 are randomly dispersed throughout the clusters that form upon TCR engagement. The segregation of LAT and SLP-76 develops near the end of the spreading process. The local concentration of LAT also increases at the same time. Both changes require TCR activation and an intact actin cytoskeleton. These results demonstrate that the nanoscale organization of LAT-based signaling complexes is dynamic and indicates that different kinds of LAT-based complexes appear at different times during T cell activation.
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Affiliation(s)
- Valarie A Barr
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA
| | - Eilon Sherman
- Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
| | - Jason Yi
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA
| | - Itoro Akpan
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA
| | | | - Lawrence E Samelson
- Laboratory of Cellular and Molecular Biology, CCR, NCI, NIH, Bethesda, MD 20892, USA
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35
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Mathematical Models for Immunology: Current State of the Art and Future Research Directions. Bull Math Biol 2016; 78:2091-2134. [PMID: 27714570 PMCID: PMC5069344 DOI: 10.1007/s11538-016-0214-9] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 09/26/2016] [Indexed: 01/01/2023]
Abstract
The advances in genetics and biochemistry that have taken place over the last 10 years led to significant advances in experimental and clinical immunology. In turn, this has led to the development of new mathematical models to investigate qualitatively and quantitatively various open questions in immunology. In this study we present a review of some research areas in mathematical immunology that evolved over the last 10 years. To this end, we take a step-by-step approach in discussing a range of models derived to study the dynamics of both the innate and immune responses at the molecular, cellular and tissue scales. To emphasise the use of mathematics in modelling in this area, we also review some of the mathematical tools used to investigate these models. Finally, we discuss some future trends in both experimental immunology and mathematical immunology for the upcoming years.
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36
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Trahtemberg U, Grau A, Tabib A, Atallah M, Krispin A, Mevorach D. Identification and Characterization of Two Human Monocyte-Derived Dendritic Cell Subpopulations with Different Functions in Dying Cell Clearance and Different Patterns of Cell Death. PLoS One 2016; 11:e0162984. [PMID: 27690130 PMCID: PMC5045195 DOI: 10.1371/journal.pone.0162984] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 08/31/2016] [Indexed: 12/23/2022] Open
Abstract
Human monocyte-derived dendritic cells (mdDCs) are versatile cells that are used widely for research and experimental therapies. Although different culture conditions can affect their characteristics, there are no known subpopulations. Since monocytes differentiate into dendritic cells (DCs) in a variety of tissues and contexts, we asked whether they can give rise to different subpopulations. In this work we set out to characterize two human mdDC subpopulations that we identified and termed small (DC-S) and large (DC-L). Morphologically, DC-L are larger, more granular and have a more complex cell membrane. Phenotypically, DC-L show higher expression of a wide panel of surface molecules and stronger responses to maturation stimuli. Transcriptomic analysis confirmed their separate identities and findings were consistent with the phenotypes observed. Although they show similar apoptotic cell uptake, DC-L have different capabilities for phagocytosis, demonstrate better antigen processing, and have significantly better necrotic cell uptake. These subpopulations also have different patterns of cell death, with DC-L presenting an inflammatory, "dangerous" phenotype while DC-S mostly downregulate their surface markers upon cell death. Apoptotic cells induce an immune-suppressed phenotype, which becomes more pronounced among DC-L, especially after the addition of lipopolysaccharide. We propose that these two subpopulations correspond to inflammatory (DC-L) and steady-state (DC-S) DC classes that have been previously described in mice and humans.
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Affiliation(s)
- Uriel Trahtemberg
- The Laboratory for Cellular and Molecular Immunology, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Amir Grau
- The Laboratory for Cellular and Molecular Immunology, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Adi Tabib
- The Laboratory for Cellular and Molecular Immunology, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Mizhir Atallah
- The Laboratory for Cellular and Molecular Immunology, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Alon Krispin
- The Laboratory for Cellular and Molecular Immunology, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Dror Mevorach
- The Laboratory for Cellular and Molecular Immunology, Department of Medicine, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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37
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Chen Y, Russell SM. Mediating signaling response to actin-mediated forces: Cas-L is causal in the T-cell response to forces triggered by antigen presentation. Immunol Cell Biol 2016; 94:905-906. [PMID: 27645156 DOI: 10.1038/icb.2016.79] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ye Chen
- Immune Signalling Laboratory, Research Division, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia.,Centre for Micro-Photonics, School of Science, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, Victoria, Australia
| | - Sarah M Russell
- Immune Signalling Laboratory, Research Division, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia.,Centre for Micro-Photonics, School of Science, Faculty of Science, Engineering and Technology, Swinburne University of Technology, Hawthorn, Victoria, Australia.,Department of Pathology, The University of Melbourne, Victoria, Australia.,Sir Peter MacCallum Department of Oncology, The University of Melbourne, Victoria, Australia
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38
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Christensen SM, Tu HL, Jun JE, Alvarez S, Triplet MG, Iwig JS, Yadav KK, Bar-Sagi D, Roose JP, Groves JT. One-way membrane trafficking of SOS in receptor-triggered Ras activation. Nat Struct Mol Biol 2016; 23:838-46. [PMID: 27501536 PMCID: PMC5016256 DOI: 10.1038/nsmb.3275] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 07/08/2016] [Indexed: 02/07/2023]
Abstract
SOS is a key activator of the small GTPase Ras. In cells, SOS-Ras signaling is thought to be initiated predominantly by membrane recruitment of SOS via the adaptor Grb2 and balanced by rapidly reversible Grb2-SOS binding kinetics. However, SOS has multiple protein and lipid interactions that provide linkage to the membrane. In reconstituted-membrane experiments, these Grb2-independent interactions were sufficient to retain human SOS on the membrane for many minutes, during which a single SOS molecule could processively activate thousands of Ras molecules. These observations raised questions concerning how receptors maintain control of SOS in cells and how membrane-recruited SOS is ultimately released. We addressed these questions in quantitative assays of reconstituted SOS-deficient chicken B-cell signaling systems combined with single-molecule measurements in supported membranes. These studies revealed an essentially one-way trafficking process in which membrane-recruited SOS remains trapped on the membrane and continuously activates Ras until being actively removed via endocytosis.
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Affiliation(s)
- Sune M. Christensen
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Hsiung-Lin Tu
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Jesse E. Jun
- Department of Anatomy, University of California, San Francisco, California, USA
| | - Steven Alvarez
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Meredith G. Triplet
- Department of Chemistry, University of California, Berkeley, California, USA
| | - Jeffrey S. Iwig
- Howard Hughes Medical Institute, Department of Molecular and Cell Biology, University of California, Berkeley, California, USA
| | - Kamlesh K. Yadav
- Department of Biochemistry, New York University School of Medicine, New York, USA
| | - Dafna Bar-Sagi
- Department of Biochemistry, New York University School of Medicine, New York, USA
| | - Jeroen P. Roose
- Department of Anatomy, University of California, San Francisco, California, USA
| | - Jay T. Groves
- Department of Chemistry, University of California, Berkeley, California, USA
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39
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Sherman E, Barr VA, Merrill RK, Regan CK, Sommers CL, Samelson LE. Hierarchical nanostructure and synergy of multimolecular signalling complexes. Nat Commun 2016; 7:12161. [PMID: 27396911 PMCID: PMC4942584 DOI: 10.1038/ncomms12161] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2015] [Accepted: 06/07/2016] [Indexed: 01/15/2023] Open
Abstract
Signalling complexes are dynamic, multimolecular structures and sites for intracellular signal transduction. Although they play a crucial role in cellular activation, current research techniques fail to resolve their structure in intact cells. Here we present a multicolour, photoactivated localization microscopy approach for imaging multiple types of single molecules in fixed and live cells and statistical tools to determine the nanoscale organization, topology and synergy of molecular interactions in signalling complexes downstream of the T-cell antigen receptor. We observe that signalling complexes nucleated at the key adapter LAT show a hierarchical topology. The critical enzymes PLCγ1 and VAV1 localize to the centre of LAT-based complexes, and the adapter SLP-76 and actin molecules localize to the periphery. Conditional second-order statistics reveal a hierarchical network of synergic interactions between these molecules. Our results extend our understanding of the nanostructure of signalling complexes and are relevant to studying a wide range of multimolecular complexes.
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Affiliation(s)
- Eilon Sherman
- Racah Institute of Physics, The Hebrew University,
Jerusalem
91904, Israel
| | - Valarie A. Barr
- Laboratory of Cellular and Molecular Biology, CCR, NCI,
NIH, Bethesda, Maryland
20892, USA
| | - Robert K. Merrill
- Laboratory of Cellular and Molecular Biology, CCR, NCI,
NIH, Bethesda, Maryland
20892, USA
| | - Carole K. Regan
- Laboratory of Cellular and Molecular Biology, CCR, NCI,
NIH, Bethesda, Maryland
20892, USA
| | - Connie L. Sommers
- Laboratory of Cellular and Molecular Biology, CCR, NCI,
NIH, Bethesda, Maryland
20892, USA
| | - Lawrence E. Samelson
- Laboratory of Cellular and Molecular Biology, CCR, NCI,
NIH, Bethesda, Maryland
20892, USA
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40
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Sherman E. Resolving protein interactions and organization downstream the T cell antigen receptor using single-molecule localization microscopy: a review. Methods Appl Fluoresc 2016. [DOI: 10.1088/2050-6120/4/2/022002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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41
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Abstract
Cytotoxic T lymphocytes (CTLs) kill virus-infected and tumour cells with remarkable specificity. Upon recognition, CTLs form a cytolytic immune synapse with their target cell, and marked reorganization of both the actin and the microtubule cytoskeletons brings the centrosome up to the plasma membrane to the point of T cell receptor signalling. Secretory granules move towards the centrosome and are delivered to this focal point of secretion. Such centrosomal docking at the plasma membrane also occurs during ciliogenesis; indeed, striking similarities exist between the cytolytic synapse and the primary cilium that throw light on the possible origins of immune synapses.
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Affiliation(s)
- Maike de la Roche
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
- CRUK-Cambridge Research Institute, Cambridge CB2 0RE, UK
| | - Yukako Asano
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Gillian M Griffiths
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
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42
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Abstract
T-cell protein microclusters have until recently been investigable only as microscale entities with their composition and structure being discerned by biochemistry or diffraction-limited light microscopy. With the advent of super resolution microscopy comes the ability to interrogate the structure and function of these clusters at the single molecule level by producing highly accurate pointillist maps of single molecule locations at ~20nm resolution. Analysis tools have also been developed to provide rich descriptors of the pointillist data, allowing us to pose questions about the nanoscale organization which governs the local and cell wide responses required of a migratory T-cell.
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43
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Pietronigro E, Zenaro E, Constantin G. Imaging of Leukocyte Trafficking in Alzheimer's Disease. Front Immunol 2016; 7:33. [PMID: 26913031 PMCID: PMC4753285 DOI: 10.3389/fimmu.2016.00033] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 01/23/2016] [Indexed: 12/17/2022] Open
Abstract
Alzheimer's disease (AD) is the most common neurodegenerative disorder and is characterized by a progressive decline of cognitive functions. The neuropathological features of AD include amyloid beta (Aβ) deposition, intracellular neurofibrillary tangles derived from the cytoskeletal hyperphosphorylated tau protein, amyloid angiopathy, the loss of synapses, and neuronal degeneration. In the last decade, inflammation has emerged as a key feature of AD, but most studies have focused on the role of microglia-driven neuroinflammation mechanisms. A dysfunctional blood-brain barrier has also been implicated in the pathogenesis of AD, and several studies have demonstrated that the vascular deposition of Aβ induces the expression of adhesion molecules and alters the expression of tight junction proteins, potentially facilitating the transmigration of circulating leukocytes. Two-photon laser scanning microscopy (TPLSM) has become an indispensable tool to dissect the molecular mechanisms controlling leukocyte trafficking in the central nervous system (CNS). Recent TPLSM studies have shown that vascular deposition of Aβ in the CNS promotes intraluminal neutrophil adhesion and crawling on the brain endothelium and also that neutrophils extravasate in the parenchyma preferentially in areas with Aβ deposits. These studies have also highlighted a role for LFA-1 integrin in neutrophil accumulation in the CNS of AD-like disease models, revealing that LFA-1 inhibition reduces the corresponding cognitive deficit and AD neuropathology. In this article, we consider how current imaging techniques can help to unravel new inflammation mechanisms in the pathogenesis of AD and identify novel therapeutic strategies to treat the disease by interfering with leukocyte trafficking mechanisms.
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Affiliation(s)
- Enrica Pietronigro
- Section of General Pathology, Department of Medicine, University of Verona , Verona , Italy
| | - Elena Zenaro
- Section of General Pathology, Department of Medicine, University of Verona , Verona , Italy
| | - Gabriela Constantin
- Section of General Pathology, Department of Medicine, University of Verona , Verona , Italy
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44
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Martinelli R, Carman CV. An Endothelial Planar Cell Model for Imaging Immunological Synapse Dynamics. J Vis Exp 2015:e53288. [PMID: 26780561 DOI: 10.3791/53288] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Adaptive immunity is regulated by dynamic interactions between T cells and antigen presenting cells ('APCs') referred to as 'immunological synapses'. Within these intimate cell-cell interfaces discrete sub-cellular clusters of MHC/Ag-TCR, F-actin, adhesion and signaling molecules form and remodel rapidly. These dynamics are thought to be critical determinants of both the efficiency and quality of the immune responses that develop and therefore of protective versus pathologic immunity. Current understanding of immunological synapses with physiologic APCs is limited by the inadequacy of the obtainable imaging resolution. Though artificial substrate models (e.g., planar lipid bilayers) offer excellent resolution and have been extremely valuable tools, they are inherently non-physiologic and oversimplified. Vascular and lymphatic endothelial cells have emerged as an important peripheral tissue (or stromal) compartment of 'semi-professional APCs'. These APCs (which express most of the molecular machinery of professional APCs) have the unique feature of forming virtually planar cell surface and are readily transfectable (e.g., with fluorescent protein reporters). Herein a basic approach to implement endothelial cells as a novel and physiologic 'planar cellular APC model' for improved imaging and interrogation of fundamental antigenic signaling processes will be described.
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45
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Yoon J, Kim K, Park H, Choi C, Jang S, Park Y. Label-free characterization of white blood cells by measuring 3D refractive index maps. BIOMEDICAL OPTICS EXPRESS 2015; 6:3865-75. [PMID: 26504637 PMCID: PMC4605046 DOI: 10.1364/boe.6.003865] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Revised: 08/07/2015] [Accepted: 09/01/2015] [Indexed: 05/02/2023]
Abstract
The characterization of white blood cells (WBCs) is crucial for blood analyses and disease diagnoses. However, current standard techniques rely on cell labeling, a process which imposes significant limitations. Here we present three-dimensional (3D) optical measurements and the label-free characterization of mouse WBCs using optical diffraction tomography. 3D refractive index (RI) tomograms of individual WBCs are constructed from multiple two-dimensional quantitative phase images of samples illuminated at various angles of incidence. Measurements of the 3D RI tomogram of WBCs enable the separation of heterogeneous populations of WBCs using quantitative morphological and biochemical information. Time-lapse tomographic measurements also provide the 3D trajectory of micrometer-sized beads ingested by WBCs. These results demonstrate that optical diffraction tomography can be a useful and versatile tool for the study of WBCs.
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Affiliation(s)
- Jonghee Yoon
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
| | - Kyoohyun Kim
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
| | - HyunJoo Park
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
| | - Chulhee Choi
- Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
| | - Seongsoo Jang
- Department of Laboratory Medicine, University of Ulsan, College of Medicine and Asan Medical Center, Seoul 138-736, South Korea
| | - YongKeun Park
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, South Korea
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46
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Ito Y, Sakata-Sogawa K, Tokunaga M. A facile preparation of glass-supported lipid bilayers for analyzing molecular dynamics. ANAL SCI 2015; 30:1103-6. [PMID: 25492457 DOI: 10.2116/analsci.30.1103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Many research programs focus on the molecular dynamics of living cells. This research requires cells to be adhered to a substrate while retaining the innate motility of their surface molecules. Lipid bilayer-based systems fulfill this requirement, although current methods are complicated and their utility is limited. We developed a simple and rapid method for reproducible preparation of homogeneous glass-supported lipid bilayers. Our method provides a facile means for bioimaging and analysis of molecular dynamics in living cells.
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Affiliation(s)
- Yuma Ito
- Department of Biological Information, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology
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47
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Ritter AT, Asano Y, Stinchcombe JC, Dieckmann NMG, Chen BC, Gawden-Bone C, van Engelenburg S, Legant W, Gao L, Davidson MW, Betzig E, Lippincott-Schwartz J, Griffiths GM. Actin depletion initiates events leading to granule secretion at the immunological synapse. Immunity 2015; 42:864-76. [PMID: 25992860 PMCID: PMC4448150 DOI: 10.1016/j.immuni.2015.04.013] [Citation(s) in RCA: 217] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 12/20/2014] [Accepted: 03/15/2015] [Indexed: 11/29/2022]
Abstract
Cytotoxic T lymphocytes (CTLs) use polarized secretion to rapidly destroy virally infected and tumor cells. To understand the temporal relationships between key events leading to secretion, we used high-resolution 4D imaging. CTLs approached targets with actin-rich projections at the leading edge, creating an initially actin-enriched contact with rearward-flowing actin. Within 1 min, cortical actin reduced across the synapse, T cell receptors (TCRs) clustered centrally to form the central supramolecular activation cluster (cSMAC), and centrosome polarization began. Granules clustered around the moving centrosome within 2.5 min and reached the synapse after 6 min. TCR-bearing intracellular vesicles were delivered to the cSMAC as the centrosome docked. We found that the centrosome and granules were delivered to an area of membrane with reduced cortical actin density and phospholipid PIP2. These data resolve the temporal order of events during synapse maturation in 4D and reveal a critical role for actin depletion in regulating secretion. 4D imaging elucidates the order of events leading to secretion Actin depletion initiates events leading to centrosome polarization and secretion Lattice light-sheet imaging reveals a rearward flow of actin away from the synapse Both centrosome and granules are delivered to an area of membrane depleted of actin
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Affiliation(s)
- Alex T Ritter
- Cambridge Institute for Medical Research, University of Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK; National Institute of Child Health and Disease, NIH, Bethesda, MD 20892, USA
| | - Yukako Asano
- Cambridge Institute for Medical Research, University of Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Jane C Stinchcombe
- Cambridge Institute for Medical Research, University of Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - N M G Dieckmann
- Cambridge Institute for Medical Research, University of Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Bi-Chang Chen
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - C Gawden-Bone
- Cambridge Institute for Medical Research, University of Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | | | - Wesley Legant
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Liang Gao
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Michael W Davidson
- National High Magnetic Field Laboratory and Department of Biological Science, Florida State University, Tallahassee, FL 32304, USA
| | - Eric Betzig
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | | | - Gillian M Griffiths
- Cambridge Institute for Medical Research, University of Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.
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48
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Liubchenko GA, Moriev RM, Kholodna LS. Modern fluorescent techniques to investigate the mechanisms of lymphocyte activation. UKRAINIAN BIOCHEMICAL JOURNAL 2015; 87:33-45. [PMID: 26036129 DOI: 10.15407/ubj87.01.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Fluorescent proteins are promising toolsfor studying intracellular signaling processes in lymphocytes. This brief review summarizes fluorescence-based imaging techniques developed in recent years and discusses new methodological advances, such as fluorescent photoswitches, fluorescence recovery after photobleaching (FRAP), fluorescent resonance energy transfer (FRET), fluorescence lifetime imaging microscopy (FLIM), photoactivated localization microscopy (PALM), stochastic optical reconstruction microscopy (STORM), stimulated emission depletion (STED), total internal reflection fluorescence (TIRF) and other techiques. This survey also highlights recent advances in vitro imaging of live tissues, novel applications of flow cytometry with genetically modifed fluorescent proteins, and future prospects for the development of new immunological test systems based on fluorescent protein technology.
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Molecular mechanisms and functional implications of polarized actin remodeling at the T cell immunological synapse. Cell Mol Life Sci 2014; 72:537-556. [PMID: 25355055 DOI: 10.1007/s00018-014-1760-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 09/22/2014] [Accepted: 10/13/2014] [Indexed: 02/05/2023]
Abstract
Transient,specialized cell-cell interactions play a central role in leukocyte function by enabling specific intercellular communication in the context of a highly dynamic systems level response. The dramatic structural changes required for the formation of these contacts are driven by rapid and precise cytoskeletal remodeling events. In recent years, the immunological synapse that forms between a T lymphocyte and its antigen-presenting target cell has emerged as an important model system for understanding immune cell interactions. In this review, we discuss how regulators of the cortical actin cytoskeleton control synaptic architecture and in this way specify T cell function.
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Neve-Oz Y, Razvag Y, Sajman J, Sherman E. Mechanisms of localized activation of the T cell antigen receptor inside clusters. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:810-21. [PMID: 25300584 DOI: 10.1016/j.bbamcr.2014.09.025] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 09/07/2014] [Accepted: 09/29/2014] [Indexed: 01/21/2023]
Abstract
The T cell antigen receptor (TCR) has been shown to cluster both before and upon engagement with cognate antigens. However, the effect of TCR clustering on its activation remains poorly understood. Here, we used two-color photo-activated localization microscopy (PALM) to visualize individual molecules of TCR and ZAP-70, as a marker of TCR activation and phosphorylation, at the plasma membrane of uniformly activated T cells. Imaging and second-order statistics revealed that ZAP-70 recruitment and TCR activation localized inside TCR clusters. Live cell PALM imaging showed that the extent of localized TCR activation decreased, yet remained significant, with cell spreading. Using dynamic modeling and Monte-Carlo simulations we evaluated possible mechanisms of localized TCR activation. Our simulations indicate that localized TCR activation is the result of long-range cooperative interactions between activated TCRs, or localized activation by Lck and Fyn. Our results demonstrate the role of molecular clustering in cell signaling and activation, and are relevant to studying a wide range of multi-molecular complexes. This article is part of a Special Issue entitled: Nanoscale membrane organisation and signalling.
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Affiliation(s)
- Yair Neve-Oz
- Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
| | - Yair Razvag
- Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
| | - Julia Sajman
- Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel
| | - Eilon Sherman
- Racah Institute of Physics, The Hebrew University, Jerusalem 91904, Israel.
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