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Liu J, Tan YY, Zheng W, Wang Y, Ju LA, Su QP. Nanoscale insights into hematology: super-resolved imaging on blood cell structure, function, and pathology. J Nanobiotechnology 2024; 22:363. [PMID: 38910248 PMCID: PMC11194919 DOI: 10.1186/s12951-024-02605-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 05/30/2024] [Indexed: 06/25/2024] Open
Abstract
Fluorescence nanoscopy, also known as super-resolution microscopy, has transcended the conventional resolution barriers and enabled visualization of biological samples at nanometric resolutions. A series of super-resolution techniques have been developed and applied to investigate the molecular distribution, organization, and interactions in blood cells, as well as the underlying mechanisms of blood-cell-associated diseases. In this review, we provide an overview of various fluorescence nanoscopy technologies, outlining their current development stage and the challenges they are facing in terms of functionality and practicality. We specifically explore how these innovations have propelled forward the analysis of thrombocytes (platelets), erythrocytes (red blood cells) and leukocytes (white blood cells), shedding light on the nanoscale arrangement of subcellular components and molecular interactions. We spotlight novel biomarkers uncovered by fluorescence nanoscopy for disease diagnosis, such as thrombocytopathies, malignancies, and infectious diseases. Furthermore, we discuss the technological hurdles and chart out prospective avenues for future research directions. This review aims to underscore the significant contributions of fluorescence nanoscopy to the field of blood cell analysis and disease diagnosis, poised to revolutionize our approach to exploring, understanding, and managing disease at the molecular level.
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Affiliation(s)
- Jinghan Liu
- School of Biomedical Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Yuping Yolanda Tan
- Charles Perkins Centre, The University of Sydney, Camperdown, NSW, 2006, Australia
- Heart Research Institute, Newtown, NSW, 2042, Australia
| | - Wen Zheng
- School of Biomedical Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia
| | - Yao Wang
- School of Biomedical Engineering, The University of Sydney, Darlington, NSW, 2008, Australia
| | - Lining Arnold Ju
- School of Biomedical Engineering, The University of Sydney, Darlington, NSW, 2008, Australia
- Charles Perkins Centre, The University of Sydney, Camperdown, NSW, 2006, Australia
- Heart Research Institute, Newtown, NSW, 2042, Australia
| | - Qian Peter Su
- School of Biomedical Engineering, University of Technology Sydney, Sydney, NSW, 2007, Australia.
- Heart Research Institute, Newtown, NSW, 2042, Australia.
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2
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Bertalan G, Duparc R, Krepuska M, Toth D, Madjidyar J, Thurner P, Schubert T, Kulcsar Z. Dynamic Perviousness Predicts Revascularization Success in Acute Ischemic Stroke. Diagnostics (Basel) 2024; 14:535. [PMID: 38473007 DOI: 10.3390/diagnostics14050535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Revised: 02/29/2024] [Accepted: 03/01/2024] [Indexed: 03/14/2024] Open
Abstract
BACKGROUND The predictive value of thrombus perviousness in acute ischemic stroke (AIS), as measured by computed tomography (CT), has been intensively studied with conflicting results. In this study, we investigate the predictive potential of the novel concept of dynamic perviousness using three-dimensional (3D) volumetric evaluation of occlusive thrombi. METHODS The full thrombus volume in 65 patients with a hyperdense artery sign on non-contrast CT (NCCT), who underwent mechanical thrombectomy (MT), was segmented. Perviousness maps were computed voxel-wise for the entire thrombus volume as thrombus attenuation increase (TAI) between NCCT and CT angiography (CTA) as well as between CTA and late venous phase CT (CTV). Perviousness was analyzed for its association with NIHSS at admission, Thrombolysis In Cerebral Infarction (TICI) score, and number of MT passes. RESULTS The mean late-uptake TAI of thrombi with NIHSS scores greater than 21 at admission was approximately 100% higher than for lower scored NIHSS (p between 0.05 and 0.005). Concerning revascularization results, thrombi requiring less than four MT passes had ca. 80% higher group mean late-uptake TAI than clots requiring four or more passes (p = 0.03), and thrombi with TICI score III had ca. 95% higher group mean late-uptake TAI than thrombi with TICI II (p = 0.03). Standard perviousness showed no significant correlation with MT results. CONCLUSION Standard thrombus perviousness of 3D clot volume is not associated with revascularization results in AIS. In contrast, dynamic perviousness assessed with a voxel-wise characterization of 3D thrombi volume may be a better predictor of MT outcomes than standard perviousness.
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Affiliation(s)
- Gergely Bertalan
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091 Zürich, Switzerland
| | - Roxane Duparc
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091 Zürich, Switzerland
| | - Miklos Krepuska
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091 Zürich, Switzerland
| | - Daniel Toth
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091 Zürich, Switzerland
| | - Jawid Madjidyar
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091 Zürich, Switzerland
| | - Patrick Thurner
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091 Zürich, Switzerland
| | - Tilman Schubert
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091 Zürich, Switzerland
| | - Zsolt Kulcsar
- Department of Neuroradiology, University Hospital Zürich, Frauenklinikstrasse 10, 8091 Zürich, Switzerland
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3
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Wang C, Wojtynek M, Medalia O. Structural investigation of eukaryotic cells: From the periphery to the interior by cryo-electron tomography. Adv Biol Regul 2023; 87:100923. [PMID: 36280452 DOI: 10.1016/j.jbior.2022.100923] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/05/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022]
Abstract
Cryo-electron tomography (cryo-ET) combines a close-to-life preservation of the cell with high-resolution three-dimensional (3D) imaging. This allows to study the molecular architecture of the cellular landscape and provides unprecedented views on biological processes and structures. In this review we mainly focus on the application of cryo-ET to visualize and structurally characterize eukaryotic cells - from the periphery to the cellular interior. We discuss strategies that can be employed to investigate the structure of challenging targets in their cellular environment as well as the application of complimentary approaches in conjunction with cryo-ET.
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Affiliation(s)
- Chunyang Wang
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Matthias Wojtynek
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.
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4
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Platelets’ Nanomechanics and Morphology in Neurodegenerative Pathologies. Biomedicines 2022; 10:biomedicines10092239. [PMID: 36140340 PMCID: PMC9496241 DOI: 10.3390/biomedicines10092239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Revised: 08/26/2022] [Accepted: 08/30/2022] [Indexed: 11/17/2022] Open
Abstract
The imaging and force–distance curve modes of atomic force microscopy (AFM) are explored to compare the morphological and mechanical signatures of platelets from patients diagnosed with classical neurodegenerative diseases (NDDs) and healthy individuals. Our data demonstrate the potential of AFM to distinguish between the three NDDs—Parkinson’s disease (PD), amyotrophic lateral sclerosis (ALS) and Alzheimer’s disease (AD), and normal healthy platelets. The common features of platelets in the three pathologies are reduced membrane surface roughness, area and height, and enhanced nanomechanics in comparison with healthy cells. These changes might be related to general phenomena associated with reorganization in the platelet membrane morphology and cytoskeleton, a key factor for all platelets’ functions. Importantly, the platelets’ signatures are modified to a different extent in the three pathologies, most significant in ALS, less pronounced in PD and the least in AD platelets, which shows the specificity associated with each pathology. Moreover, different degree of activation, distinct pseudopodia and nanocluster formation characterize ALS, PD and AD platelets. The strongest alterations in the biophysical properties correlate with the highest activation of ALS platelets, which reflect the most significant changes in their nanoarchitecture. The specific platelet signatures that mark each of the studied pathologies can be added as novel biomarkers to the currently used diagnostic tools.
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5
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Navarrete S, Solar C, Tapia R, Pereira J, Fuentes E, Palomo I. Pathophysiology of deep vein thrombosis. Clin Exp Med 2022:10.1007/s10238-022-00829-w. [PMID: 35471714 DOI: 10.1007/s10238-022-00829-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 03/31/2022] [Indexed: 12/29/2022]
Abstract
Deep venous thrombosis is a frequent, multifactorial disease and a leading cause of morbidity and mortality. Most of the time deep venous thrombosis is triggered by the interaction between acquired risk factors, such as hip fracture, pregnancy, and immobility, and hereditary risk factors such as thrombophilias. The mechanisms underlying deep venous thrombosis are not fully elucidated; however, in recent years, important advances have shed light on the role of venous flow, endothelium, platelets, leukocytes, and the interaction between inflammation and hemostasis. It has been described that the alteration of venous blood flow produces endothelial activation, favoring the adhesion of platelets and leukocytes, which, through tissue factor expression and neutrophil extracellular traps formation, contribute to the activation of coagulation, trapping more cells, such as red blood cells. Thus, the concerted interaction of these phenomena allows the formation and growth of the thrombus. In this work, the main mechanisms involved in the pathophysiology of deep vein thrombosis will be described.
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Affiliation(s)
- Simón Navarrete
- Thrombosis Research Center, Medical Technology School, Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Universidad de Talca, Av. Lircay s/n, 3460000, Talca, Chile
| | - Carla Solar
- Thrombosis Research Center, Medical Technology School, Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Universidad de Talca, Av. Lircay s/n, 3460000, Talca, Chile
| | | | - Jaime Pereira
- Department of Hematology-Oncology, School of Medicine, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Eduardo Fuentes
- Thrombosis Research Center, Medical Technology School, Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Universidad de Talca, Av. Lircay s/n, 3460000, Talca, Chile
| | - Iván Palomo
- Thrombosis Research Center, Medical Technology School, Department of Clinical Biochemistry and Immunohaematology, Faculty of Health Sciences, Universidad de Talca, Av. Lircay s/n, 3460000, Talca, Chile.
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6
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Sachs L, Wesche J, Lenkeit L, Greinacher A, Bender M, Otto O, Palankar R. Ex vivo anticoagulants affect human blood platelet biomechanics with implications for high-throughput functional mechanophenotyping. Commun Biol 2022; 5:86. [PMID: 35064207 PMCID: PMC8782918 DOI: 10.1038/s42003-021-02982-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 12/17/2021] [Indexed: 11/30/2022] Open
Abstract
Inherited platelet disorders affecting the human platelet cytoskeleton result in increased bleeding risk. However, deciphering their impact on cytoskeleton-dependent intrinsic biomechanics of platelets remains challenging and represents an unmet need from a diagnostic and prognostic perspective. It is currently unclear whether ex vivo anticoagulants used during collection of peripheral blood impact the mechanophenotype of cellular components of blood. Using unbiased, high-throughput functional mechanophenotyping of single human platelets by real-time deformability cytometry, we found that ex vivo anticoagulants are a critical pre-analytical variable that differentially influences platelet deformation, their size, and functional response to agonists by altering the cytoskeleton. We applied our findings to characterize the functional mechanophenotype of platelets from a patient with Myosin Heavy Chain 9 (MYH9) related macrothrombocytopenia. Our data suggest that platelets from MYH9 p.E1841K mutation in humans affecting platelet non-muscle myosin heavy chain IIa (NMMHC-IIA) are biomechanically less deformable in comparison to platelets from healthy individuals. Sachs et al. examine the effects of different ex vivo anticoagulants on the biomechanical and functional properties of single platelets using high-throughput real-time fluorescence and deformability cytometry (RT-FDC). Their results demonstrate that the choice of ex vivo anticoagulant may strongly impact the outcomes of mechanophenotyping.
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7
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Seifert J, von Eysmondt H, Chatterjee M, Gawaz M, Schäffer TE. Effect of Oxidized LDL on Platelet Shape, Spreading, and Migration Investigated with Deep Learning Platelet Morphometry. Cells 2021; 10:2932. [PMID: 34831155 PMCID: PMC8616354 DOI: 10.3390/cells10112932] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Revised: 10/15/2021] [Accepted: 10/22/2021] [Indexed: 12/17/2022] Open
Abstract
Platelets are functionally versatile blood cells involved in thrombosis, hemostasis, atherosclerosis, and immune response. Platelet interaction with the immediate microenvironment in blood, vasculature, and tissues alters platelet morphology. The quantification of platelet morphodynamics by geometrical parameters (morphometry) can provide important insights into how platelets sense and respond to stimulatory cues in their vicinity. However, the extraction of platelet shapes from phase contrast microscopy images by conventional image processing is difficult. Here, we used a convolutional neural network (CNN) to develop a deep-learning-based approach for the unbiased extraction of information on platelet morphodynamics by phase contrast microscopy. We then investigated the effect of normal and oxidized low-density lipoproteins (LDL, oxLDL) on platelet morphodynamics, spreading, and haptotactic migration. Exposure of platelets to oxLDL led to a decreased spreading area and rate on fibrinogen, accompanied by increased formation of filopodia and impaired formation of lamellipodia. Haptotactic platelet migration was affected by both LDL and oxLDL in terms of decreased migration velocity and reduced directional persistence. Our results demonstrate the use of deep learning in investigating platelet morphodynamics and reveal differential effects of LDL and oxLDL on platelet morphology and platelet-matrix interaction.
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Affiliation(s)
- Jan Seifert
- Institute of Applied Physics, University of Tübingen, 72076 Tübingen, Germany; (J.S.); (H.v.E.)
| | - Hendrik von Eysmondt
- Institute of Applied Physics, University of Tübingen, 72076 Tübingen, Germany; (J.S.); (H.v.E.)
| | - Madhumita Chatterjee
- Department of Cardiology and Angiology, University of Tübingen, 72076 Tübingen, Germany; (M.C.); (M.G.)
| | - Meinrad Gawaz
- Department of Cardiology and Angiology, University of Tübingen, 72076 Tübingen, Germany; (M.C.); (M.G.)
| | - Tilman E. Schäffer
- Institute of Applied Physics, University of Tübingen, 72076 Tübingen, Germany; (J.S.); (H.v.E.)
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8
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Structural analysis of receptors and actin polarity in platelet protrusions. Proc Natl Acad Sci U S A 2021; 118:2105004118. [PMID: 34504018 PMCID: PMC8449362 DOI: 10.1073/pnas.2105004118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2021] [Indexed: 11/18/2022] Open
Abstract
During activation the platelet cytoskeleton is reorganized, inducing adhesion to the extracellular matrix and cell spreading. These processes are critical for wound healing and clot formation. Initially, this task relies on the formation of strong cellular-extracellular matrix interactions, exposed in subendothelial lesions. Despite the medical relevance of these processes, there is a lack of high-resolution structural information on the platelet cytoskeleton controlling cell spreading and adhesion. Here, we present in situ structural analysis of membrane receptors and the underlying cytoskeleton in platelet protrusions by applying cryoelectron tomography to intact platelets. We utilized three-dimensional averaging procedures to study receptors at the plasma membrane. Analysis of substrate interaction-free receptors yielded one main structural class resolved to 26 Å, resembling the αIIbβ3 integrin folded conformation. Furthermore, structural analysis of the actin network in pseudopodia indicates a nonuniform polarity of filaments. This organization would allow generation of the contractile forces required for integrin-mediated cell adhesion.
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9
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O’Sullivan LR, Cahill MR, Young PW. The Importance of Alpha-Actinin Proteins in Platelet Formation and Function, and Their Causative Role in Congenital Macrothrombocytopenia. Int J Mol Sci 2021; 22:9363. [PMID: 34502272 PMCID: PMC8431150 DOI: 10.3390/ijms22179363] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 08/25/2021] [Accepted: 08/26/2021] [Indexed: 12/04/2022] Open
Abstract
The actin cytoskeleton plays a central role in platelet formation and function. Alpha-actinins (actinins) are actin filament crosslinking proteins that are prominently expressed in platelets and have been studied in relation to their role in platelet activation since the 1970s. However, within the past decade, several groups have described mutations in ACTN1/actinin-1 that cause congenital macrothrombocytopenia (CMTP)-accounting for approximately 5% of all cases of this condition. These findings are suggestive of potentially novel functions for actinins in platelet formation from megakaryocytes in the bone marrow and/or platelet maturation in circulation. Here, we review some recent insights into the well-known functions of actinins in platelet activation before considering possible roles for actinins in platelet formation that could explain their association with CMTP. We describe what is known about the consequences of CMTP-linked mutations on actinin-1 function at a molecular and cellular level and speculate how these changes might lead to the alterations in platelet count and morphology observed in CMTP patients. Finally, we outline some unanswered questions in this area and how they might be addressed in future studies.
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Affiliation(s)
- Leanne R. O’Sullivan
- School of Biochemistry & Cell Biology, University College Cork, T12 XF62 Cork, Ireland;
| | - Mary R. Cahill
- Department of Haematology and CancerResearch@UCC, Cork University Hospital, University College Cork, T12 XF62 Cork, Ireland;
| | - Paul W. Young
- School of Biochemistry & Cell Biology, University College Cork, T12 XF62 Cork, Ireland;
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10
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Sapra KT, Qin Z, Dubrovsky-Gaupp A, Aebi U, Müller DJ, Buehler MJ, Medalia O. Nonlinear mechanics of lamin filaments and the meshwork topology build an emergent nuclear lamina. Nat Commun 2020; 11:6205. [PMID: 33277502 PMCID: PMC7718915 DOI: 10.1038/s41467-020-20049-8] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 11/11/2020] [Indexed: 01/16/2023] Open
Abstract
The nuclear lamina—a meshwork of intermediate filaments termed lamins—is primarily responsible for the mechanical stability of the nucleus in multicellular organisms. However, structural-mechanical characterization of lamin filaments assembled in situ remains elusive. Here, we apply an integrative approach combining atomic force microscopy, cryo-electron tomography, network analysis, and molecular dynamics simulations to directly measure the mechanical response of single lamin filaments in three-dimensional meshwork. Endogenous lamin filaments portray non-Hookean behavior – they deform reversibly at a few hundred picoNewtons and stiffen at nanoNewton forces. The filaments are extensible, strong and tough similar to natural silk and superior to the synthetic polymer Kevlar®. Graph theory analysis shows that the lamin meshwork is not a random arrangement of filaments but exhibits small-world properties. Our results suggest that lamin filaments arrange to form an emergent meshwork whose topology dictates the mechanical properties of individual filaments. The quantitative insights imply a role of meshwork topology in laminopathies. Mechanical strength of in situ assembled nuclear lamin filaments arranged in a 3D meshwork is unclear. Here, using mechanical, structural and simulation tools, the authors report the hierarchical organization of the lamin meshwork that imparts strength and toughness to lamin filaments at par with silk and Kevlar®
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Affiliation(s)
- K Tanuj Sapra
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland. .,Department of Biosystems Science and Bioengineering, ETH Zurich, Mattenstrasse 26, 4058, Basel, Switzerland.
| | - Zhao Qin
- Laboratory for Atomistic and Molecular Mechanics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.,Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY, 13244, USA
| | - Anna Dubrovsky-Gaupp
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland
| | - Ueli Aebi
- Biozentrum, University of Basel, CH-4056, Basel, Switzerland
| | - Daniel J Müller
- Department of Biosystems Science and Bioengineering, ETH Zurich, Mattenstrasse 26, 4058, Basel, Switzerland
| | - Markus J Buehler
- Laboratory for Atomistic and Molecular Mechanics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.
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11
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Turk M, Baumeister W. The promise and the challenges of cryo-electron tomography. FEBS Lett 2020; 594:3243-3261. [PMID: 33020915 DOI: 10.1002/1873-3468.13948] [Citation(s) in RCA: 144] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 09/28/2020] [Accepted: 09/28/2020] [Indexed: 01/11/2023]
Abstract
Structural biologists have traditionally approached cellular complexity in a reductionist manner in which the cellular molecular components are fractionated and purified before being studied individually. This 'divide and conquer' approach has been highly successful. However, awareness has grown in recent years that biological functions can rarely be attributed to individual macromolecules. Most cellular functions arise from their concerted action, and there is thus a need for methods enabling structural studies performed in situ, ideally in unperturbed cellular environments. Cryo-electron tomography (Cryo-ET) combines the power of 3D molecular-level imaging with the best structural preservation that is physically possible to achieve. Thus, it has a unique potential to reveal the supramolecular architecture or 'molecular sociology' of cells and to discover the unexpected. Here, we review state-of-the-art Cryo-ET workflows, provide examples of biological applications, and discuss what is needed to realize the full potential of Cryo-ET.
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Affiliation(s)
- Martin Turk
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Wolfgang Baumeister
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany
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12
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Tenga R, Medalia O. Structure and unique mechanical aspects of nuclear lamin filaments. Curr Opin Struct Biol 2020; 64:152-159. [DOI: 10.1016/j.sbi.2020.06.017] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 06/15/2020] [Accepted: 06/21/2020] [Indexed: 11/15/2022]
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13
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Tomaiuolo M, Litvinov RI, Weisel JW, Stalker TJ. Use of electron microscopy to study platelets and thrombi. Platelets 2020; 31:580-588. [PMID: 32423268 PMCID: PMC7332414 DOI: 10.1080/09537104.2020.1763939] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/22/2020] [Accepted: 04/27/2020] [Indexed: 01/23/2023]
Abstract
Electron microscopy has been a valuable tool for the study of platelet biology and thrombosis for more than 70 years. Early studies using conventional transmission and scanning electron microscopy (EM) provided a foundation for our initial understanding of platelet structure and how it changes upon platelet activation. EM approaches have since been utilized to study platelets and thrombi in the context of basic, translational and clinical research, and they are instrumental in the diagnosis of multiple platelet function disorders. In this brief review, we provide a sampling of the many contributions EM based studies have made to the field, including both historical highlights and contemporary applications. We will also discuss exciting new imaging modalities based on EM and their utility for the study of platelets, hemostasis and thrombosis into the future.
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Affiliation(s)
| | - Rustem I. Litvinov
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
| | - John W. Weisel
- Department of Cell and Developmental Biology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, USA
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14
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Sachs L, Denker C, Greinacher A, Palankar R. Quantifying single-platelet biomechanics: An outsider's guide to biophysical methods and recent advances. Res Pract Thromb Haemost 2020; 4:386-401. [PMID: 32211573 PMCID: PMC7086474 DOI: 10.1002/rth2.12313] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Revised: 12/10/2019] [Accepted: 01/07/2020] [Indexed: 01/30/2023] Open
Abstract
Platelets are the key cellular components of blood primarily contributing to formation of stable hemostatic plugs at the site of vascular injury, thus preventing excessive blood loss. On the other hand, excessive platelet activation can contribute to thrombosis. Platelets respond to many stimuli that can be of biochemical, cellular, or physical origin. This drives platelet activation kinetics and plays a vital role in physiological and pathological situations. Currently used bulk assays are inadequate for comprehensive biomechanical assessment of single platelets. Individual platelets interact and respond differentially while modulating their biomechanical behavior depending on dynamic changes that occur in surrounding microenvironments. Quantitative description of such a phenomenon at single-platelet regime and up to nanometer resolution requires methodological approaches that can manipulate individual platelets at submicron scales. This review focusses on principles, specific examples, and limitations of several relevant biophysical methods applied to single-platelet analysis such as micropipette aspiration, atomic force microscopy, scanning ion conductance microscopy and traction force microscopy. Additionally, we are introducing a promising single-cell approach, real-time deformability cytometry, as an emerging biophysical method for high-throughput biomechanical characterization of single platelets. This review serves as an introductory guide for clinician scientists and beginners interested in exploring one or more of the above-mentioned biophysical methods to address outstanding questions in single-platelet biomechanics.
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Affiliation(s)
- Laura Sachs
- Institute of Immunology and Transfusion MedicineUniversity Medicine GreifswaldGreifswaldGermany
| | | | - Andreas Greinacher
- Institute of Immunology and Transfusion MedicineUniversity Medicine GreifswaldGreifswaldGermany
| | - Raghavendra Palankar
- Institute of Immunology and Transfusion MedicineUniversity Medicine GreifswaldGreifswaldGermany
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15
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Ludhiadch A, Muralidharan A, Balyan R, Munshi A. The molecular basis of platelet biogenesis, activation, aggregation and implications in neurological disorders. Int J Neurosci 2020; 130:1237-1249. [PMID: 32069430 DOI: 10.1080/00207454.2020.1732372] [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: 10/25/2022]
Abstract
Platelets are anucleated blood constituents, vital for hemostasis and involved in the pathophysiology of several cardiovascular, neurovascular diseases as well as inflammatory processes and metastasis. Over the past few years, the molecular processes that regulate the function of platelets in hemostasis and thrombosis have emerged revealing platelets to be perhaps more complex than may have been expected. The most understood part of platelets is to respond to a blood vessel injury by altering shape, secreting granule contents, and aggregating. These responses, while advantageous for hemostasis, can become detrimental when they root ischemia or infarction. Only a few transcription and signaling factors involved in platelet biogenesis have been identified till date. Platelets encompass an astonishingly complete array of organelles and storage granules including mitochondria, lysosomes, alpha granules, dense granules, a dense tubular system (analogous to the endoplasmic reticulum of nucleated cells); a highly invaginated plasma membrane system known as the open canalicular system (OCS) and large fields of glycogen. Platelets as a model cells to study neurological disorders have been recommended by several researchers since several counterparts exist between platelets and the brain, which make them interesting for studying the neurobiology of various neurological disorders. This review has been compiled with an aim to integrate the latest research on platelet biogenesis, activation and aggregation focusing on the molecular pathways that power and regulate these processes. The dysregulation of important molecular players affecting fluctuating platelet biology and thereby resulting in neurovascular diseases has also been discussed.
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Affiliation(s)
- Abhilash Ludhiadch
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab, India
| | - Abhishek Muralidharan
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab, India
| | - Renuka Balyan
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab, India
| | - Anjana Munshi
- Department of Human Genetics and Molecular Medicine, Central University of Punjab, Bathinda, Punjab, India
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16
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Toro-Nahuelpan M, Zagoriy I, Senger F, Blanchoin L, Théry M, Mahamid J. Tailoring cryo-electron microscopy grids by photo-micropatterning for in-cell structural studies. Nat Methods 2020; 17:50-54. [PMID: 31740821 DOI: 10.21203/rs.2.12377/v1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 10/07/2019] [Indexed: 05/22/2023]
Abstract
Spatially controlled cell adhesion on electron microscopy supports remains a bottleneck in specimen preparation for cellular cryo-electron tomography. Here, we describe contactless and mask-free photo-micropatterning of electron microscopy grids for site-specific deposition of extracellular matrix-related proteins. We attained refined cell positioning for micromachining by cryo-focused ion beam milling. Complex micropatterns generated predictable intracellular organization, allowing direct correlation between cell architecture and in-cell three-dimensional structural characterization of the underlying molecular machinery.
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Affiliation(s)
- Mauricio Toro-Nahuelpan
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Ievgeniia Zagoriy
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Fabrice Senger
- CytomorphoLab, Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire et Végétale, Université Grenoble-Alpes/CEA/CNRS/INRA, Grenoble, France
| | - Laurent Blanchoin
- CytomorphoLab, Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire et Végétale, Université Grenoble-Alpes/CEA/CNRS/INRA, Grenoble, France
- CytomorphoLab, Hôpital Saint Louis, Institut Universitaire d'Hématologie, Université Paris Diderot, Paris, France
| | - Manuel Théry
- CytomorphoLab, Interdisciplinary Research Institute of Grenoble, Laboratoire de Physiologie Cellulaire et Végétale, Université Grenoble-Alpes/CEA/CNRS/INRA, Grenoble, France
- CytomorphoLab, Hôpital Saint Louis, Institut Universitaire d'Hématologie, Université Paris Diderot, Paris, France
| | - Julia Mahamid
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.
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17
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Fernández-Colino A, Wolf F, Rütten S, Schmitz-Rode T, Rodríguez-Cabello JC, Jockenhoevel S, Mela P. Small Caliber Compliant Vascular Grafts Based on Elastin-Like Recombinamers for in situ Tissue Engineering. Front Bioeng Biotechnol 2019; 7:340. [PMID: 31803735 PMCID: PMC6877483 DOI: 10.3389/fbioe.2019.00340] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 10/30/2019] [Indexed: 01/04/2023] Open
Abstract
Vascular disease is a leading cause of death worldwide, but surgical options are restricted by the limited availability of autologous vessels, and the suboptimal performance of prosthetic vascular grafts. This is especially evident for coronary artery by-pass grafts, whose small caliber is associated with a high occlusion propensity. Despite the potential of tissue-engineered grafts, compliance mismatch, dilatation, thrombus formation, and the lack of functional elastin are still major limitations leading to graft failure. This calls for advanced materials and fabrication schemes to achieve improved control on the grafts' properties and performance. Here, bioinspired materials and technical textile components are combined to create biohybrid cell-free implants for endogenous tissue regeneration. Clickable elastin-like recombinamers are processed to form an open macroporous 3D architecture to favor cell ingrowth, while being endowed with the non-thrombogenicity and the elastic behavior of the native elastin. The textile components (i.e., warp-knitted and electrospun meshes) are designed to confer suture retention, long-term structural stability, burst strength, and compliance. Notably, by controlling the electrospun layer's thickness, the compliance can be modulated over a wide range of values encompassing those of native vessels. The grafts support cell ingrowth, extracellular matrix deposition and endothelium development in vitro. Overall, the fabrication strategy results in promising off-the-shelf hemocompatible vascular implants for in situ tissue engineering by addressing the known limitations of bioartificial vessel substitutes.
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Affiliation(s)
- Alicia Fernández-Colino
- Department of Biohybrid & Medical Textiles (BioTex), AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany
| | - Frederic Wolf
- Department of Biohybrid & Medical Textiles (BioTex), AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany
| | - Stephan Rütten
- Electron Microscopy Facility, Uniklinik RWTH Aachen, Aachen, Germany
| | - Thomas Schmitz-Rode
- AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany
| | | | - Stefan Jockenhoevel
- Department of Biohybrid & Medical Textiles (BioTex), AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany.,AMIBM-Aachen-Maastricht-Institute for Biobased Materials, Maastricht University, Geleen, Netherlands
| | - Petra Mela
- Department of Biohybrid & Medical Textiles (BioTex), AME-Institute of Applied Medical Engineering, Helmholtz Institute, RWTH Aachen University, Aachen, Germany.,Medical Materials and Implants, Department of Mechanical Engineering and Munich School of BioEngineering, Technical University of Munich, Garching, Germany
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18
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Tailoring cryo-electron microscopy grids by photo-micropatterning for in-cell structural studies. Nat Methods 2019; 17:50-54. [PMID: 31740821 PMCID: PMC6949126 DOI: 10.1038/s41592-019-0630-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Accepted: 10/07/2019] [Indexed: 01/01/2023]
Abstract
Spatially-controlled cell adhesion on electron microscopy (EM) supports remains a
bottleneck in specimen preparation for cellular cryo-electron tomography. Here,
we describe contactless and mask-free photo-micropatterning of EM grids for
site-specific deposition of extracellular matrix (ECM)-related proteins. We
attained refined cell positioning for micromachining by cryo-focused ion beam
milling. Complex micropatterns generated predictable intracellular organization,
allowing direct correlation between cell architecture and
in-cell 3D-structural characterization of the underlying
molecular machinery.
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19
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Stivala S, Sorrentino S, Gobbato S, Bonetti NR, Camici GG, Lüscher TF, Medalia O, Beer JH. Glycoprotein Ib clustering in platelets can be inhibited by α-linolenic acid as revealed by cryo-electron tomography. Haematologica 2019; 105:1660-1666. [PMID: 31439672 PMCID: PMC7271563 DOI: 10.3324/haematol.2019.220988] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 08/14/2019] [Indexed: 11/26/2022] Open
Abstract
Platelet adhesion to the sub-endothelial matrix and damaged endothelium occurs through a multi-step process mediated in the initial phase by glycoprotein Ib binding to von Willebrand factor (vWF), which leads to the subsequent formation of a platelet plug. The plant-derived ω-3 fatty acid α-linolenic acid is an abundant alternative to fish-derived n-3 fatty acids and has anti-inflammatory and antithrombotic properties. In this study, we investigated the impact of α-linolenic acid on human platelet binding to vWF under high-shear flow conditions (mimicking blood flow in stenosed arteries). Pre-incubation of fresh human blood from healthy donors with α-linolenic acid at dietary relevant concentrations reduced platelet binding and rolling on vWF-coated microchannels at a shear rate of 100 dyn/cm2. Depletion of membrane cholesterol by incubation of platelet-rich plasma with methyl-β cyclodextrin abrogated platelet rolling on vWF. Analysis of glycoprotein Ib by applying cryo-electron tomography to intact platelets revealed local clusters of glycoprotein Ib complexes upon exposure to shear force: the formation of these complexes could be prevented by treatment with α-linolenic acid. This study provides novel findings on the rapid local rearrangement of glycoprotein Ib complexes in response to high-shear flow and highlights the mechanism of in vitro inhibition of platelet binding to and rolling on vWF by α-linolenic acid.
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Affiliation(s)
- Simona Stivala
- Laboratory for Platelet Research, Center for Molecular Cardiology, University of Zurich, Zurich, Switzerland
| | - Simona Sorrentino
- Department of Biochemistry, University of Zurich, Zurich, Switzerland
| | - Sara Gobbato
- Laboratory for Platelet Research, Center for Molecular Cardiology, University of Zurich, Zurich, Switzerland
| | - Nicole R Bonetti
- Laboratory for Platelet Research, Center for Molecular Cardiology, University of Zurich, Zurich, Switzerland.,Internal Medicine, Cantonal Hospital of Baden, Baden, Switzerland
| | - Giovanni G Camici
- Laboratory for Platelet Research, Center for Molecular Cardiology, University of Zurich, Zurich, Switzerland.,University Heart Center, University Hospital Zurich, Zurich, Switzerland.,Department of Research and Education, University Hospital Zurich, Zurich, Switzerland
| | - Thomas F Lüscher
- Laboratory for Platelet Research, Center for Molecular Cardiology, University of Zurich, Zurich, Switzerland
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich, Zurich, Switzerland.,Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University, Beer-Sheva, Israel
| | - Jürg H Beer
- Laboratory for Platelet Research, Center for Molecular Cardiology, University of Zurich, Zurich, Switzerland .,Internal Medicine, Cantonal Hospital of Baden, Baden, Switzerland
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20
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Weber MS, Wojtynek M, Medalia O. Cellular and Structural Studies of Eukaryotic Cells by Cryo-Electron Tomography. Cells 2019; 8:E57. [PMID: 30654455 PMCID: PMC6356268 DOI: 10.3390/cells8010057] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 01/09/2019] [Accepted: 01/10/2019] [Indexed: 11/23/2022] Open
Abstract
The architecture of protein assemblies and their remodeling during physiological processes is fundamental to cells. Therefore, providing high-resolution snapshots of macromolecular complexes in their native environment is of major importance for understanding the molecular biology of the cell. Cellular structural biology by means of cryo-electron tomography (cryo-ET) offers unique insights into cellular processes at an unprecedented resolution. Recent technological advances have enabled the detection of single impinging electrons and improved the contrast of electron microscopic imaging, thereby significantly increasing the sensitivity and resolution. Moreover, various sample preparation approaches have paved the way to observe every part of a eukaryotic cell, and even multicellular specimens, under the electron beam. Imaging of macromolecular machineries at high resolution directly within their native environment is thereby becoming reality. In this review, we discuss several sample preparation and labeling techniques that allow the visualization and identification of macromolecular assemblies in situ, and demonstrate how these methods have been used to study eukaryotic cellular landscapes.
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Affiliation(s)
- Miriam Sarah Weber
- Department of Biochemistry, University of Zürich, 8057 Zürich, Switzerland.
| | - Matthias Wojtynek
- Department of Biochemistry, University of Zürich, 8057 Zürich, Switzerland.
- Department of Biology, Institute of Biochemistry, ETH Zürich, 8093 Zürich, Switzerland.
| | - Ohad Medalia
- Department of Biochemistry, University of Zürich, 8057 Zürich, Switzerland.
- Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84120, Israel.
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21
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Tutwiler V, Mukhitov AR, Peshkova AD, Le Minh G, Khismatullin RR, Vicksman J, Nagaswami C, Litvinov RI, Weisel JW. Shape changes of erythrocytes during blood clot contraction and the structure of polyhedrocytes. Sci Rep 2018; 8:17907. [PMID: 30559364 PMCID: PMC6297136 DOI: 10.1038/s41598-018-35849-8] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 09/26/2018] [Indexed: 02/03/2023] Open
Abstract
Polyhedral erythrocytes, named polyhedrocytes, are formed in contracted blood clots and thrombi, as a result of compression by activated contractile platelets pulling on fibrin. This deformation was shown to be mechanical in nature and polyhedrocytes were characterized using light and electron microscopy. Through three-dimensional reconstruction, we quantified the geometry of biconcave, intermediate, and polyhedral erythrocytes within contracting blood clots. During compression, erythrocytes became less oblate and more prolate than the biconcave cells and largely corresponded to convex, irregular polyhedra with a total number of faces ranging from 10 to 16. Faces were polygons with 3 to 6 sides. The majority of the faces were quadrilaterals, though not all sides were straight and not all faces were flat. There were no changes in the surface area or volume. These results describe the gradual natural deformation of erythrocytes as a part of compaction into a tightly packed array that is an important but understudied component of mature blood clots and thrombi.
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Affiliation(s)
- Valerie Tutwiler
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Alexander R Mukhitov
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Alina D Peshkova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
| | - Giang Le Minh
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russian Federation
| | - R R Khismatullin
- Department of General Pathology, Kazan State Medical University, Kazan, Russian Federation
| | - Jacqueline Vicksman
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Chandrasekaran Nagaswami
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - Rustem I Litvinov
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
| | - John W Weisel
- Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
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22
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Wei H, Malcor JDM, Harper MT. Lipid rafts are essential for release of phosphatidylserine-exposing extracellular vesicles from platelets. Sci Rep 2018; 8:9987. [PMID: 29968812 PMCID: PMC6030044 DOI: 10.1038/s41598-018-28363-4] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 06/21/2018] [Indexed: 12/21/2022] Open
Abstract
Platelets protect the vascular system during damage or inflammation, but platelet activation can result in pathological thrombosis. Activated platelets release a variety of extracellular vesicles (EVs). EVs shed from the plasma membrane often expose phosphatidylserine (PS). These EVs are pro-thrombotic and increased in number in many cardiovascular and metabolic diseases. The mechanisms by which PS-exposing EVs are shed from activated platelets are not well characterised. Cholesterol-rich lipid rafts provide a platform for coordinating signalling through receptors and Ca2+ channels in platelets. We show that cholesterol depletion with methyl-β-cyclodextrin or sequestration with filipin prevented the Ca2+-triggered release of PS-exposing EVs. Although calpain activity was required for release of PS-exposing, calpain-dependent cleavage of talin was not affected by cholesterol depletion. P2Y12 and TPα, receptors for ADP and thromboxane A2, respectively, have been reported to be in platelet lipid rafts. However, the P2Y12 antagonist, AR-C69931MX, or the cyclooxygenase inhibitor, aspirin, had no effect on A23187-induced release of PS-exposing EVs. Together, these data show that lipid rafts are required for release of PS-exposing EVs from platelets.
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Affiliation(s)
- Hao Wei
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom
| | | | - Matthew T Harper
- Department of Pharmacology, University of Cambridge, Cambridge, United Kingdom.
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