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Milosevic M, Simic V, Nikolic A, Shao N, Kawamura Hashimoto C, Godin B, Leonard F, Liu X, Kojic M. Modeling critical interaction for metastasis between circulating tumor cells (CTCs) and platelets adhered to the capillary wall. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2023; 242:107810. [PMID: 37769417 DOI: 10.1016/j.cmpb.2023.107810] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/16/2023] [Accepted: 09/11/2023] [Indexed: 09/30/2023]
Abstract
BACKGROUND AND OBJECTIVE We used a 2D fluid-solid interaction (FSI) model to investigate the critical conditions for the arrest of the CTCs traveling through the narrowed capillary with a platelet attached to the capillary wall. This computational model allows us to determine the deformations and the progression of the passage of the CTC through different types of microvessels with platelet included. METHODS The modeling process is obtained using the strong coupling approach following the remeshing procedure. Also, the 1D FE rope element for simulating active ligand-receptor bonds is implemented in our computational tool (described below). RESULTS A relationship between the CTCs properties (size and stiffness), the platelet size and stiffness, and the ligand-receptor interaction intensity, on one side, and the time in contact between the CTCs and platelet and conditions for the cell arrest, on the other side, are determined. The model is further validated in vitro by using a microfluidic device with metastatic breast tumor cells. CONCLUSIONS The computational framework that is presented, with accompanying results, can be used as a powerful tool to study biomechanical conditions for CTCs arrest in interaction with platelets, giving a prognosis of disease progression.
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Affiliation(s)
- Miljan Milosevic
- Bioengineering Research and Development Center, BioIRC, Prvoslava Stojanovica 6, 34 000 Kragujevac, Serbia; Institute for Information Technologies, University of Kragujevac, Jovana Cvijica, 34 000 Kragujevac, Serbia; Belgrade Metropolitan University, Tadeuša Košćuška 63, 11158 Belgrade, Serbia
| | - Vladimir Simic
- Bioengineering Research and Development Center, BioIRC, Prvoslava Stojanovica 6, 34 000 Kragujevac, Serbia; Institute for Information Technologies, University of Kragujevac, Jovana Cvijica, 34 000 Kragujevac, Serbia
| | - Aleksandar Nikolic
- The Institute for Artificial Intelligence Research and Development of Serbia, Fruskogorska 1, 21 000 Novi Sad, Serbia
| | - Ning Shao
- Houston Methodist Research Institute, Department of Nanomedicine, 6670 Bertner Ave, Houston, TX 77030, United States
| | - Chihiro Kawamura Hashimoto
- Houston Methodist Research Institute, Department of Nanomedicine, 6670 Bertner Ave, Houston, TX 77030, United States; Houston Methodist Research Institute, Department of Neurology, 6670 Bertner Ave, Houston, TX 77030, United States
| | - Biana Godin
- Houston Methodist Research Institute, Department of Nanomedicine, 6670 Bertner Ave, Houston, TX 77030, United States
| | - Fransisca Leonard
- Houston Methodist Research Institute, Department of Nanomedicine, 6670 Bertner Ave, Houston, TX 77030, United States; Houston Methodist Research Institute, Department of Neurology, 6670 Bertner Ave, Houston, TX 77030, United States
| | - Xuewu Liu
- Houston Methodist Research Institute, Department of Nanomedicine, 6670 Bertner Ave, Houston, TX 77030, United States
| | - Milos Kojic
- Bioengineering Research and Development Center, BioIRC, Prvoslava Stojanovica 6, 34 000 Kragujevac, Serbia; Houston Methodist Research Institute, Department of Nanomedicine, 6670 Bertner Ave, Houston, TX 77030, United States; Serbian Academy of Sciences and Arts, Kneza Mihaila 35, 11 000 Belgrade, Serbia
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2
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Seifert J, Rheinlaender J, von Eysmondt H, Schäffer TE. Mechanics of migrating platelets investigated with scanning ion conductance microscopy. NANOSCALE 2022; 14:8192-8199. [PMID: 35621412 DOI: 10.1039/d2nr01187e] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Platelets are small blood cells involved in hemostasis, wound healing, and immune response. After adhesion and spreading, platelets can migrate at sites of injury inducing an early immune response to inflammation or infection. Platelet migration requires fibrinogen-integrin binding and fibrinogen depletion from the substrate inducing a self-generated ligand gradient guiding the direction of migration. This type of cellular motion is referred to as haptotactic migration. The underlying mechanisms of haptotactic platelet migration have just recently been discovered, but the connection to platelet mechanics has remained unknown yet. Using scanning ion conductance microscopy (SICM), we investigated the three-dimensional morphology and mechanics of platelets during haptotactic migration for the first time. Migrating platelets showed a polarized, anisotropic shape oriented in the direction of migration. This polarization goes hand in hand with a characteristic subcellular stiffness distribution showing a region of increased stiffness at the leading edge. Moreover, the mechanical properties of the leading edge revealed a highly dynamic stiffening and softening process with rapid changes of the elastic modulus by a factor of up to 5× per minute. Inhibition of actin polymerization stopped the dynamic stiffening and softening process and halted the migration. By combining SICM with confocal fluorescence microscopy, we found that the increased stiffness and mechanical dynamics at the leading edge coincided with an increased volumetric F-actin density. Our data provide a connection between platelet mechanics and the cytoskeletal contribution to the migration process of platelets.
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Affiliation(s)
- Jan Seifert
- Institute of Applied Physics, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany.
| | - Johannes Rheinlaender
- Institute of Applied Physics, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany.
| | - Hendrik von Eysmondt
- Institute of Applied Physics, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany.
| | - Tilman E Schäffer
- Institute of Applied Physics, University of Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany.
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3
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Baumann J, Sachs L, Otto O, Schoen I, Nestler P, Zaninetti C, Kenny M, Kranz R, von Eysmondt H, Rodriguez J, Schäffer TE, Nagy Z, Greinacher A, Palankar R, Bender M. Reduced platelet forces underlie impaired hemostasis in mouse models of MYH9-related disease. SCIENCE ADVANCES 2022; 8:eabn2627. [PMID: 35584211 PMCID: PMC9116608 DOI: 10.1126/sciadv.abn2627] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
MYH9-related disease patients with mutations in the contractile protein nonmuscle myosin heavy chain IIA display, among others, macrothrombocytopenia and a mild-to-moderate bleeding tendency. In this study, we used three mouse lines, each with one point mutation in the Myh9 gene at positions 702, 1424, or 1841, to investigate mechanisms underlying the increased bleeding risk. Agonist-induced activation of Myh9 mutant platelets was comparable to controls. However, myosin light chain phosphorylation after activation was reduced in mutant platelets, which displayed altered biophysical characteristics and generated lower adhesion, interaction, and traction forces. Treatment with tranexamic acid restored clot retraction in the presence of tPA and reduced bleeding. We verified our findings from the mutant mice with platelets from patients with the respective mutation. These data suggest that reduced platelet forces lead to an increased bleeding tendency in patients with MYH9-related disease, and treatment with tranexamic acid can improve the hemostatic function.
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Affiliation(s)
- Juliane Baumann
- Institute of Experimental Biomedicine—Chair I, University Hospital and Rudolf Virchow Center, Würzburg, Germany
| | - Laura Sachs
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany
| | - Oliver Otto
- Zentrum für Innovationskompetenz—Humorale Immunreaktionen bei Kardiovaskulären Erkrankungen, University Greifswald, Greifswald, Germany
- Deutsches Zentrum für Herz-Kreislauf-Forschung e. V., Standort Greifswald, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Ingmar Schoen
- School of Pharmacy and Biomolecular Sciences, Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Peter Nestler
- Zentrum für Innovationskompetenz—Humorale Immunreaktionen bei Kardiovaskulären Erkrankungen, University Greifswald, Greifswald, Germany
| | - Carlo Zaninetti
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany
- University of Pavia, Pavia, Italy
| | - Martin Kenny
- School of Pharmacy and Biomolecular Sciences, Irish Centre for Vascular Biology, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Ruth Kranz
- Institute of Experimental Biomedicine—Chair I, University Hospital and Rudolf Virchow Center, Würzburg, Germany
| | | | - Johanna Rodriguez
- Institute of Applied Physics, University of Tübingen, Tübingen, Germany
| | | | - Zoltan Nagy
- Institute of Experimental Biomedicine—Chair I, University Hospital and Rudolf Virchow Center, Würzburg, Germany
| | - Andreas Greinacher
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany
| | - Raghavendra Palankar
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald, Germany
- Corresponding author. (M.B.); (R.P.)
| | - Markus Bender
- Institute of Experimental Biomedicine—Chair I, University Hospital and Rudolf Virchow Center, Würzburg, Germany
- Corresponding author. (M.B.); (R.P.)
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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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Platelet ACKR3/CXCR7 Favors Anti-Platelet Lipids over an Atherothrombotic Lipidome and Regulates Thrombo-inflammation. Blood 2021; 139:1722-1742. [PMID: 34905596 DOI: 10.1182/blood.2021013097] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 11/30/2021] [Indexed: 11/20/2022] Open
Abstract
Platelet ACKR3/CXCR7 surface expression is enhanced and influences prognosis in coronary artery disease-(CAD) patients, who exhibit a distinct atherothrombotic platelet lipidome. Current investigation validates the potential of ACKR3/CXCR7 in regulating thrombo-inflammatory response, through its impact on the platelet lipidome. CAD patients-(n=230) with enhanced platelet-ACKR3/CXCR7 expression exhibited reduced aggregation. Pharmacological CXCR7-agonist-(VUF11207) significantly reduced pro-thrombotic platelet response in blood from ACS patients-(n=11) ex vivo. CXCR7-agonist administration reduced thrombotic functions and thrombo-inflammatory platelet-leukocyte interactions post myocardial infarction-(MI) and arterial injury in vivo. ACKR3/CXCR7-ligation did not affect surface availability of GPIbα, GPV, GPVI, GPIX, αv-integrin, β3-integrin, coagulation profile-(APTT, PT), bleeding time, plasma-dependent thrombin generation-(thrombinoscopy) or clot formation-(thromboelastography), but counteracted activation-induced phosphatidylserine exposure and procoagulant platelet-assisted thrombin generation. Targeted-(micro-UHPLC-ESI-QTrap-MS/MS) and untargeted-(UHPLC-ESI-QTOF-MS/MS) lipidomics analysis revealed that ACKR3/CXCR7-ligation favored generation of anti-thrombotic lipids-(dihomo-γ-linolenic acid-DGLA, 12-hydroxyeicosatrienoic acid-12-HETrE) over cyclooxygenase-COX-1-(thromboxane-TxA2), or 12-lipoxygenase-LOX-(12-HETE) metabolized pro-thrombotic, and phospholipase derived atherogenic-(lysophosphatidylcholine-LPC) lipids, in healthy subjects and CAD patients, contrary to anti-platelet therapy. Through 12-HETrE, ACKR3/CXCR7-ligation coordinated with Gαs-coupled prostacyclin receptor-(IP) to trigger cAMP-PKA mediated platelet inhibition. ACKR3/CXCR7-ligation reduced generation of lipid agonists-(arachidonic acid-AA,TxA2), lipid signaling intermediates-(lyophosphatidylinositol-LPI, diacylglycerol-DG), which affected calcium mobilization, intracellular signaling, consequently platelet interaction with physiological matrices and thrombo-inflammatory secretion-(IL1β,IFN-γ,TGF-β,IL-8), emphasizing its functional dichotomy from pro-thrombotic CXCR4. Moreover, CXCR7-agonist regulated heparin-induced thrombocytopenia-(HIT)-sera/IgG-induced platelet and neutrophil activation, heparin induced platelet aggregation-(HIPA), generation of COX-1-(TxA2), 12-LOX-(12-HETE) derived thrombo-inflammatory lipids, platelet-neutrophil aggregate formation, and thrombo-inflammatory secretion (sCD40L, IL-1β, IFN-γ, TNF-α, sP-selectin, IL-8, tissue factor-TF) ex vivo. Therefore, ACKR3/CXCR7 may offer a novel therapeutic strategy in acute/chronic thrombo-inflammation exaggerated cardiovascular pathologies, and CAD.
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6
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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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7
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Abstract
Scanning ion conductance microscopy (SICM) has emerged as a versatile tool for studies of interfaces in biology and materials science with notable utility in biophysical and electrochemical measurements. The heart of the SICM is a nanometer-scale electrolyte filled glass pipette that serves as a scanning probe. In the initial conception, manipulations of ion currents through the tip of the pipette and appropriate positioning hardware provided a route to recording micro- and nanoscopic mapping of the topography of surfaces. Subsequent advances in instrumentation, probe design, and methods significantly increased opportunities for SICM beyond recording topography. Hybridization of SICM with coincident characterization techniques such as optical microscopy and faradaic electrodes have brought SICM to the forefront as a tool for nanoscale chemical measurement for a wide range of applications. Modern approaches to SICM realize an important tool in analytical, bioanalytical, biophysical, and materials measurements, where significant opportunities remain for further exploration. In this review, we chronicle the development of SICM from the perspective of both the development of instrumentation and methods and the breadth of measurements performed.
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Affiliation(s)
- Cheng Zhu
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Kaixiang Huang
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Natasha P Siepser
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Lane A Baker
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
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8
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Zhuang J, Yan H, Zheng Q, Wang T, Liao X. Study on a Rapid Imaging Method for Scanning Ion Conductance Microscopy Using a Double-Barreled Theta Pipette. Anal Chem 2020; 92:15789-15798. [PMID: 33283496 DOI: 10.1021/acs.analchem.0c02840] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Scanning ion conductance microscopy (SICM) is a new noncontact, high-resolution scanning probe microscopy technique, which has become increasingly popular in recent years. The hopping mode-currently the most widely used scanning mode-can be used for imaging samples with complicated surface topographies. However, its slow scanning rate seriously restricts its broader application. This paper proposes a fast imaging control mode using a double-barreled theta pipette as the probe, which effectively increases the imaging rate. In this mode, sample surface height information is obtained when the double-barreled theta pipette approaches the sample in a two-step downward process. The ion current sum of two barrels and ion current of one barrel are used as feedback signals to approach the sample until the feedback signals decrease to the set threshold, respectively, thereby obtaining the height of the imaging point. First, this work used COMSOL to establish an SICM model and perform simulation analysis. The simulation results verified the proposed method's feasibility. Second, a scanning time mathematical model was established. The results revealed that the new method is superior to the traditional method in terms of imaging rate. Finally, experiments were performed on poly(dimethylsiloxane) (PDMS) samples using the two imaging modes described above. The results demonstrated that the new scanning mode could significantly improve the imaging rate of SICM without a loss in imaging quality and stability.
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Affiliation(s)
- Jian Zhuang
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China.,School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Heng Yan
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China.,School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Qiangqiang Zheng
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China.,School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Tingkai Wang
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China.,School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China
| | - Xiaobo Liao
- Key Laboratory of Education Ministry for Modern Design Rotor-Bearing System, Xi'an Jiaotong University, Xi'an 710049, China.,School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049, China.,School of Manufacturing Science and Engineering, Key Laboratory of Testing Technology for Manufacturing Process, Ministry of Education, Southwest University of Science and Technology, Mianyang 621010, China
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9
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Zelená A, Isbaner S, Ruhlandt D, Chizhik A, Cassini C, Klymchenko AS, Enderlein J, Chizhik A, Köster S. Time-resolved MIET measurements of blood platelet spreading and adhesion. NANOSCALE 2020; 12:21306-21315. [PMID: 33073832 DOI: 10.1039/d0nr05611a] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Human blood platelets are non-nucleated fragments of megakaryocytes and of high importance for early hemostasis. To form a blood clot, platelets adhere to the blood vessel wall, spread and attract other platelets. Despite the importance for biomedicine, the exact mechanism of platelet spreading and adhesion to surfaces remains elusive. Here, we employ metal-induced energy transfer (MIET) imaging with a leaflet-specific fluorescent membrane probe to quantitatively determine, with nanometer resolution and in a time-resolved manner, the height profile of the basal and the apical platelet membrane above a rigid substrate during platelet spreading. We observe areas, where the platelet membrane approaches the substrate particularly closely and these areas are stable on a time scale of minutes. Time-resolved MIET measurements reveal distinct behaviors of the outermost rim and the central part of the platelets, respectively. Our findings quantify platelet adhesion and spreading and improve our understanding of early steps in blood clotting. Furthermore, the results of this study demonstrate the potential of MIET for simultaneous imaging of two close-by membranes and thus three-dimensional reconstruction of the cell shape.
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Affiliation(s)
- Anna Zelená
- Institute for X-Ray Physics, University of Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen, Germany.
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10
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Sadoul K, Lafanechère L, Grichine A. Live imaging of single platelets at work. Platelets 2020; 31:551-558. [PMID: 31880193 DOI: 10.1080/09537104.2019.1708886] [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
Although live imaging of dynamic processes in platelets is a challenging task, several important observations have been published during the last 20 years. We will discuss the amazing insights that have been achieved, the difficulties that can be encountered as well as some questions still open and the future technical perspectives.
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Affiliation(s)
- Karin Sadoul
- Institute for Advanced Biosciences, University Grenoble Alpes , Grenoble, France
| | - Laurence Lafanechère
- Institute for Advanced Biosciences, University Grenoble Alpes , Grenoble, France
| | - Alexei Grichine
- Institute for Advanced Biosciences, University Grenoble Alpes , Grenoble, France
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11
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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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12
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Simeonov S, Schäffer TE. Ultrafast Imaging of Cardiomyocyte Contractions by Combining Scanning Ion Conductance Microscopy with a Microelectrode Array. Anal Chem 2019; 91:9648-9655. [PMID: 31247725 DOI: 10.1021/acs.analchem.9b01092] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Beating cardiomyocytes undergo fast morphodynamics during the contraction-relaxation cycle. However, imaging these morphodynamics with a high spatial and temporal resolution is difficult, owing to a lack of suitable techniques. Here, we combine scanning ion conductance microscopy (SICM) with a microelectrode array (MEA) to image the three-dimensional (3D) topography of cardiomyocytes during a contraction-relaxation cycle with 1 μm spatial and 1 ms time resolution. We record the vertical motion of cardiomyocytes at many locations across a cell by SICM and synchronize these data using the simultaneously recorded action potential by the MEA as a time reference. This allows us to reconstruct the time-resolved 3D morphology of cardiomyocytes during a full contraction-relaxation cycle with a raw data rate of 200 μs/frame and to generate spatially resolved images of contractile parameters (maximum displacement, time delay, asymmetry factor). We use the MEA-SICM setup to visualize the effect of blebbistatin, a myosin II inhibitor, on the morphodynamics of contractions. Further, we find an upper limit of 0.02% for cell volume changes during an action potential. The results show that MEA-SICM provides an ultrafast imaging platform for investigating the functional interplay of cardiomyocyte electrophysiology and mechanics.
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Affiliation(s)
- Stefan Simeonov
- Institute of Applied Physics , University of Tübingen , Auf der Morgenstelle 10 , 72076 Tübingen , Germany
| | - Tilman E Schäffer
- Institute of Applied Physics , University of Tübingen , Auf der Morgenstelle 10 , 72076 Tübingen , Germany
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13
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Plaut JS, Strzelecka-Kiliszek A, Bozycki L, Pikula S, Buchet R, Mebarek S, Chadli M, Bolean M, Simao AMS, Ciancaglini P, Magrini A, Rosato N, Magne D, Girard-Egrot A, Farquharson C, Esener SC, Millan JL, Bottini M. Quantitative atomic force microscopy provides new insight into matrix vesicle mineralization. Arch Biochem Biophys 2019; 667:14-21. [PMID: 30998909 DOI: 10.1016/j.abb.2019.04.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Revised: 04/11/2019] [Accepted: 04/13/2019] [Indexed: 12/22/2022]
Abstract
Matrix vesicles (MVs) are a class of extracellular vesicles that initiate mineralization in cartilage, bone, and other vertebrate tissues by accumulating calcium ions (Ca2+) and inorganic phosphate (Pi) within their lumen and forming a nucleation core (NC). After further sequestration of Ca2+ and Pi, the NC transforms into crystalline complexes. Direct evidence of the existence of the NC and its maturation have been provided solely by analyses of dried samples. We isolated MVs from chicken embryo cartilage and used atomic force microscopy peak force quantitative nanomechanical property mapping (AFM-PFQNM) to measure the nanomechanical and morphological properties of individual MVs under both mineralizing (+Ca2+) and non-mineralizing (-Ca2+) fluid conditions. The elastic modulus of MVs significantly increased by 4-fold after incubation in mineralization buffer. From AFM mapping data, we inferred the morphological changes of MVs as mineralization progresses: prior to mineralization, a punctate feature, the NC, is present within MVs and this feature grows and stiffens during mineralization until it occupies most of the MV lumen. Dynamic light scattering showed a significant increase in hydrodynamic diameter and no change in the zeta potential of hydrated MVs after incubation with Ca2+. This validates that crystalline complexes, which are strongly negative relative to MVs, were forming within the lumen of MVs. These data were substantiated by transmission electron microscopy energy dispersive X-ray and Fourier transform infrared spectroscopic analyses of dried MVs, which provide evidence that the complexes increased in size, crystallinity, and Ca/P ratio within MVs during the mineralization process.
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Affiliation(s)
- Justin S Plaut
- Cancer Early Detection Advanced Research Center, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, 97201, USA; Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - Agnieszka Strzelecka-Kiliszek
- Laboratory of Biochemistry of Lipids, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093, Warsaw, Poland
| | - Lukasz Bozycki
- Laboratory of Biochemistry of Lipids, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093, Warsaw, Poland
| | - Slawomir Pikula
- Laboratory of Biochemistry of Lipids, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 02-093, Warsaw, Poland
| | - René Buchet
- Université de Lyon, Université Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, UMR CNRS 5246, 69 622, Villeurbanne Cedex, France
| | - Saida Mebarek
- Université de Lyon, Université Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, UMR CNRS 5246, 69 622, Villeurbanne Cedex, France
| | - Meriem Chadli
- Université de Lyon, Université Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, UMR CNRS 5246, 69 622, Villeurbanne Cedex, France
| | - Maytê Bolean
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto - USP, Departamento de Química, 14040-901, Ribeirão Preto, Brazil
| | - Ana M S Simao
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto - USP, Departamento de Química, 14040-901, Ribeirão Preto, Brazil
| | - Pietro Ciancaglini
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto - USP, Departamento de Química, 14040-901, Ribeirão Preto, Brazil
| | - Andrea Magrini
- Department of Biopathology and Imaging Diagnostics, University of Rome Tor Vergata, Rome, Italy; Nanoscience & Nanotechnology & Innovative Instrumentation (NAST) Centre, University of Rome Tor Vergata, Rome, Italy
| | - Nicola Rosato
- Nanoscience & Nanotechnology & Innovative Instrumentation (NAST) Centre, University of Rome Tor Vergata, Rome, Italy; Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy
| | - David Magne
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto - USP, Departamento de Química, 14040-901, Ribeirão Preto, Brazil
| | - Agnès Girard-Egrot
- Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto - USP, Departamento de Química, 14040-901, Ribeirão Preto, Brazil
| | - Colin Farquharson
- Division of Developmental Biology, The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush, Roslin, Midlothian, Edinburgh, EH25 9RG, UK
| | - Sadik C Esener
- Cancer Early Detection Advanced Research Center, Knight Cancer Institute, Oregon Health & Science University, Portland, OR, 97201, USA; Department of Bioengineering, University of California San Diego, La Jolla, CA, 92093, USA
| | - José L Millan
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA
| | - Massimo Bottini
- Nanoscience & Nanotechnology & Innovative Instrumentation (NAST) Centre, University of Rome Tor Vergata, Rome, Italy; Department of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy; Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA.
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14
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A continuous control mode with improved imaging rate for scanning ion conductance microscope (SICM). Ultramicroscopy 2018; 190:66-76. [DOI: 10.1016/j.ultramic.2018.04.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 03/29/2018] [Accepted: 04/16/2018] [Indexed: 11/19/2022]
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15
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Hagemann P, Gesper A, Happel P. Correlative Stimulated Emission Depletion and Scanning Ion Conductance Microscopy. ACS NANO 2018; 12:5807-5815. [PMID: 29791140 DOI: 10.1021/acsnano.8b01731] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Correlation microscopy combining fluorescence and scanning probe or electron microscopy is limited to fixed samples due to the sample preparation and nonphysiological imaging conditions required by most probe or electron microscopy techniques. Among the few scanning probe techniques that allow imaging of living cells under physiological conditions, scanning ion conductance microscopy (SICM) has been shown to be the technique that minimizes the impact on the investigated sample. However, combinations of SICM and fluorescence microscopy suffered from the mismatch in resolution due to the limited resolution of conventional light microscopy. In the last years, the diffraction limit of light microscopy has been circumvented by various techniques, one of which is stimulated emission depletion (STED) microscopy. Here, we aimed at demonstrating the combination of STED and SICM. We show that both methods allow recording a living cellular specimen and provide a SICM and STED image of the same sample, which allowed us to correlate the membrane surface topography and the distribution of the cytoskeletal protein actin. Our proof-of-concept study exemplifies the benefit of correlating SICM with a subdiffraction fluorescence method and might form the basis for the development of a combined instrument that would allow the simultaneous recording of subdiffraction fluorescence and topography information.
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Affiliation(s)
- Philipp Hagemann
- Nanoscopy Group, RUBION , Ruhr-Universität Bochum , Universitätsstraße 150 , D-44801 , Bochum , Germany
| | - Astrid Gesper
- Nanoscopy Group, RUBION , Ruhr-Universität Bochum , Universitätsstraße 150 , D-44801 , Bochum , Germany
| | - Patrick Happel
- Nanoscopy Group, RUBION , Ruhr-Universität Bochum , Universitätsstraße 150 , D-44801 , Bochum , Germany
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16
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Seifert J, Rheinlaender J, Lang F, Gawaz M, Schäffer TE. Thrombin-induced cytoskeleton dynamics in spread human platelets observed with fast scanning ion conductance microscopy. Sci Rep 2017; 7:4810. [PMID: 28684746 PMCID: PMC5500533 DOI: 10.1038/s41598-017-04999-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2016] [Accepted: 05/19/2017] [Indexed: 02/08/2023] Open
Abstract
Platelets are small anucleate blood cells involved in haemostasis. Platelet activation, caused by agonists such as thrombin or by contact with the extracellular matrix, leads to platelet adhesion, aggregation, and coagulation. Activated platelets undergo shape changes, adhere, and spread at the site of injury to form a blood clot. We investigated the morphology and morphological dynamics of human platelets after complete spreading using fast scanning ion conductance microscopy (SICM). In contrast to unstimulated platelets, thrombin-stimulated platelets showed increased morphological activity after spreading and exhibited dynamic morphological changes in the form of wave-like movements of the lamellipodium and dynamic protrusions on the platelet body. The increase in morphological activity was dependent on thrombin concentration. No increase in activity was observed following exposure to other activation agonists or during contact-induced activation. Inhibition of actin polymerization and inhibition of dynein significantly decreased the activity of thrombin-stimulated platelets. Our data suggest that these morphological dynamics after spreading are thrombin-specific and might play a role in coagulation and blood clot formation.
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Affiliation(s)
- Jan Seifert
- Institute of Applied Physics, University of Tübingen, Tübingen, Germany
| | | | - Florian Lang
- Department of Physiology, University of Tübingen, Tübingen, Germany
| | - Meinrad Gawaz
- Department of Cardiology and Cardiovascular Diseases, University of Tübingen, Tübingen, Germany
| | - Tilman E Schäffer
- Institute of Applied Physics, University of Tübingen, Tübingen, Germany.
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17
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Todinova S, Komsa-Penkova R, Krumova S, Taneva SG, Golemanov G, Georgieva G, Tonchev P, Tsankov B, Beshev L, Balashev K, Andreeva TD. PlA2 Polymorphism in Glycoprotein IIb/IIIa Modulates the Morphology and Nanomechanics of Platelets. Clin Appl Thromb Hemost 2017; 23:951-960. [PMID: 28081621 DOI: 10.1177/1076029616687847] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Glycoprotein IIb/IIIa (GPIIb/IIIa) is the most abundant platelet surface receptor for fibrinogen and von Willebrand factor. Polymorphism PlA1/A2 in the gene of GPIIb/IIIa is among the risk factors for the development of arterial and venous thrombosis. The aim of this study is to evaluate the effect of the carriage of PlA1/A2 on the size, topographic features, and membrane stiffness of platelets from healthy controls and patients with deep venous thrombosis (DVT). Atomic force microscopy (AFM) imaging and nanoindentation (force-distance curves) were applied to investigate the morphological and nanomechanical properties (Young's modulus) of platelets immobilized on glass surface. The surface roughness ( Ra) and height ( h) of platelets from patients with DVT, carriers of mutant allele PlA2 ( Ra = 30.2 ± 6 nm; h = 766 ± 182 nm) and noncarriers ( Ra = 28.6 ± 6 nm; h = 865 ± 290 nm), were lower than those of healthy carriers of allele PlA2 ( Ra = 48.1 ± 12 nm; h = 1072 ± 338 nm) and healthy noncarriers ( Ra = 49.7 ± 14 nm; h = 1021 ± 433 nm), respectively. Platelets isolated from patients with DVT, both carriers and noncarriers, exhibit much higher degree of stiffness at the stage of spreading ( E = 327 ± 85 kPa and 341 ± 102 kPa, respectively) compared to healthy noncarriers ( E = 198 ± 50 kPa). In addition, more pronounced level of platelet activation was found in polymorphism carriers. In conclusion, the carriage of PlA2 allele modulates the activation state, morphology, and membrane elasticity of platelets.
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Affiliation(s)
- Svetla Todinova
- 1 Department of Biomacromolecules and Biomolecular Interactions, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | | | - Sashka Krumova
- 1 Department of Biomacromolecules and Biomolecular Interactions, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Stefka G Taneva
- 1 Department of Biomacromolecules and Biomolecular Interactions, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
| | - Georgy Golemanov
- 2 Department of Biochemistry, Medical University, Pleven, Bulgaria
| | - Galia Georgieva
- 2 Department of Biochemistry, Medical University, Pleven, Bulgaria
| | - Pencho Tonchev
- 3 Department of Surgery, University Hospital, Pleven, Bulgaria
| | - Boris Tsankov
- 3 Department of Surgery, University Hospital, Pleven, Bulgaria
| | - Lyubomir Beshev
- 3 Department of Surgery, University Hospital, Pleven, Bulgaria
| | - Konstantin Balashev
- 4 Department of Physical Chemistry, Faculty of Chemistry and Pharmacy, Sofia University, Sofia, Bulgaria
| | - Tonya D Andreeva
- 1 Department of Biomacromolecules and Biomolecular Interactions, Institute of Biophysics and Biomedical Engineering, Bulgarian Academy of Sciences, Sofia, Bulgaria
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18
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Clarke RW, Novak P, Zhukov A, Tyler EJ, Cano-Jaimez M, Drews A, Richards O, Volynski K, Bishop C, Klenerman D. Low Stress Ion Conductance Microscopy of Sub-Cellular Stiffness. SOFT MATTER 2016; 12:7953-8. [PMID: 27604678 PMCID: PMC5166566 DOI: 10.1039/c6sm01106c] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Directly examining subcellular mechanics whilst avoiding excessive strain of a live cell requires the precise control of light stress on very small areas, which is fundamentally difficult. Here we use a glass nanopipet out of contact with the plasma membrane to both exert the stress on the cell and also accurately monitor cellular compression. This allows the mapping of cell stiffness at a lateral resolution finer than 100 nm. We calculate the stress a nanopipet exerts on a cell as the sum of the intrinsic pressure between the tip face and the plasma membrane plus its direct pressure on any glycocalyx, both evaluated from the gap size in terms of the ion current decrease. A survey of cell types confirms that an intracellular pressure of approximately 120 Pa begins to detach the plasma membrane from the cytoskeleton and reveals that the first 0.66 ± 0.09 μm of compression of a neuron cell body is much softer than previous methods have been able to detect.
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Affiliation(s)
- Richard W. Clarke
- University Chemical Laboratories , Lensfield Road , Cambridge , CB2 1EW , UK . ;
| | - Pavel Novak
- School of Engineering and Materials Science , Queen Mary University of London , Mile End Road , London , E1 4NS , UK
| | - Alexander Zhukov
- University Chemical Laboratories , Lensfield Road , Cambridge , CB2 1EW , UK . ;
| | - Eleanor J. Tyler
- Centre for Cell Biology and Cutaneous Research , Queen Mary University of London , 4 Newark Street , London , E1 2AT , UK
| | | | - Anna Drews
- University Chemical Laboratories , Lensfield Road , Cambridge , CB2 1EW , UK . ;
| | - Owen Richards
- University Chemical Laboratories , Lensfield Road , Cambridge , CB2 1EW , UK . ;
| | - Kirill Volynski
- UCL Institute of Neurology , Queen Square , London , WC1N 3BG , UK
| | - Cleo Bishop
- Centre for Cell Biology and Cutaneous Research , Queen Mary University of London , 4 Newark Street , London , E1 2AT , UK
| | - David Klenerman
- University Chemical Laboratories , Lensfield Road , Cambridge , CB2 1EW , UK . ;
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19
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LeftyA decreases Actin Polymerization and Stiffness in Human Endometrial Cancer Cells. Sci Rep 2016; 6:29370. [PMID: 27404958 PMCID: PMC4941646 DOI: 10.1038/srep29370] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 06/16/2016] [Indexed: 12/27/2022] Open
Abstract
LeftyA, a cytokine regulating stemness and embryonic differentiation, down-regulates cell proliferation and migration. Cell proliferation and motility require actin reorganization, which is under control of ras-related C3 botulinum toxin substrate 1 (Rac1) and p21 protein-activated kinase 1 (PAK1). The present study explored whether LeftyA modifies actin cytoskeleton, shape and stiffness of Ishikawa cells, a well differentiated endometrial carcinoma cell line. The effect of LeftyA on globular over filamentous actin ratio was determined utilizing Western blotting and flow cytometry. Rac1 and PAK1 transcript levels were measured by qRT-PCR as well as active Rac1 and PAK1 by immunoblotting. Cell stiffness (quantified by the elastic modulus), cell surface area and cell volume were studied by atomic force microscopy (AFM). As a result, 2 hours treatment with LeftyA (25 ng/ml) significantly decreased Rac1 and PAK1 transcript levels and activity, depolymerized actin, and decreased cell stiffness, surface area and volume. The effect of LeftyA on actin polymerization was mimicked by pharmacological inhibition of Rac1 and PAK1. In the presence of the Rac1 or PAK1 inhibitor LeftyA did not lead to significant further actin depolymerization. In conclusion, LeftyA leads to disruption of Rac1 and Pak1 activity with subsequent actin depolymerization, cell softening and cell shrinkage.
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20
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Kraus MJ, Seifert J, Strasser EF, Gawaz M, Schäffer TE, Rheinlaender J. Comparative morphology analysis of live blood platelets using scanning ion conductance and robotic dark-field microscopy. Platelets 2016; 27:541-6. [PMID: 27063564 DOI: 10.3109/09537104.2016.1158400] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Many conventional microscopy techniques for investigating platelet morphology such as electron or fluorescence microscopy require highly invasive treatment of the platelets such as fixation, drying and metal coating or staining. Here, we present two unique but entirely different microscopy techniques for direct morphology analysis of live, unstained platelets: scanning ion conductance microscopy (SICM) and robotic dark-field microscopy (RDM). We demonstrate that both techniques allow for a quantitative evaluation of the morphological features of live adherent platelets. We show that their morphology can be quantified by both techniques using the same geometric parameters and therefore can be directly compared. By imaging the same identical platelets subsequently with SICM and RDM, we found that area, perimeter and circularity of the platelets are directly correlated between SICM and dark-field microscopy (DM), while the fractal dimension (FD) differed between the two microscopy techniques. We show that SICM and RDM are both valuable tools for the ex vivo investigation of the morphology of live platelets, which might contribute to new insights into the physiological and pathophysiological role of platelet spreading.
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Affiliation(s)
- Max-Joseph Kraus
- a Geiselgasteig Ambulance , Grünwald , Munich , Germany.,b Institute for Medical Engineering and Information Processing , University of Koblenz , Koblenz , Germany
| | - Jan Seifert
- c Institute of Applied Physics , University of Tübingen , Tübingen , Germany
| | - Erwin F Strasser
- d University Hospital of Erlangen , Transfusion and Haemostaseology Department , Erlangen , Germany
| | - Meinrad Gawaz
- e Department of Cardiology and Cardiovascular Diseases , University of Tübingen , Tübingen , Germany
| | - Tilman E Schäffer
- c Institute of Applied Physics , University of Tübingen , Tübingen , Germany
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21
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Weber C, Lip GYH. Editors’ Choice 2015 papers in Thrombosis and Haemostasis. Thromb Haemost 2016; 115:230-2. [DOI: 10.1160/th15-11-0911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 11/30/2015] [Indexed: 11/05/2022]
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22
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Vogel S, Bodenstein R, Chen Q, Feil S, Feil R, Rheinlaender J, Schäffer TE, Bohn E, Frick JS, Borst O, Münzer P, Walker B, Markel J, Csanyi G, Pagano PJ, Loughran P, Jessup ME, Watkins SC, Bullock GC, Sperry JL, Zuckerbraun BS, Billiar TR, Lotze MT, Gawaz M, Neal MD. Platelet-derived HMGB1 is a critical mediator of thrombosis. J Clin Invest 2015; 125:4638-54. [PMID: 26551681 DOI: 10.1172/jci81660] [Citation(s) in RCA: 238] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 10/01/2015] [Indexed: 12/16/2022] Open
Abstract
Thrombosis and inflammation are intricately linked in several major clinical disorders, including disseminated intravascular coagulation and acute ischemic events. The damage-associated molecular pattern molecule high-mobility group box 1 (HMGB1) is upregulated by activated platelets in multiple inflammatory diseases; however, the contribution of platelet-derived HMGB1 in thrombosis remains unexplored. Here, we generated transgenic mice with platelet-specific ablation of HMGB1 and determined that platelet-derived HMGB1 is a critical mediator of thrombosis. Mice lacking HMGB1 in platelets exhibited increased bleeding times as well as reduced thrombus formation, platelet aggregation, inflammation, and organ damage during experimental trauma/hemorrhagic shock. Platelets were the major source of HMGB1 within thrombi. In trauma patients, HMGB1 expression on the surface of circulating platelets was markedly upregulated. Moreover, evaluation of isolated platelets revealed that HMGB1 is critical for regulating platelet activation, granule secretion, adhesion, and spreading. These effects were mediated via TLR4- and MyD88-dependent recruitment of platelet guanylyl cyclase (GC) toward the plasma membrane, followed by MyD88/GC complex formation and activation of the cGMP-dependent protein kinase I (cGKI). Thus, we establish platelet-derived HMGB1 as an important mediator of thrombosis and identify a HMGB1-driven link between MyD88 and GC/cGKI in platelets. Additionally, these findings suggest a potential therapeutic target for patients sustaining trauma and other inflammatory disorders associated with abnormal coagulation.
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