51
|
Fritz-Laylin LK, Riel-Mehan M, Chen BC, Lord SJ, Goddard TD, Ferrin TE, Nicholson-Dykstra SM, Higgs H, Johnson GT, Betzig E, Mullins RD. Actin-based protrusions of migrating neutrophils are intrinsically lamellar and facilitate direction changes. eLife 2017; 6. [PMID: 28948912 PMCID: PMC5614560 DOI: 10.7554/elife.26990] [Citation(s) in RCA: 76] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 08/09/2017] [Indexed: 01/01/2023] Open
Abstract
Leukocytes and other amoeboid cells change shape as they move, forming highly dynamic, actin-filled pseudopods. Although we understand much about the architecture and dynamics of thin lamellipodia made by slow-moving cells on flat surfaces, conventional light microscopy lacks the spatial and temporal resolution required to track complex pseudopods of cells moving in three dimensions. We therefore employed lattice light sheet microscopy to perform three-dimensional, time-lapse imaging of neutrophil-like HL-60 cells crawling through collagen matrices. To analyze three-dimensional pseudopods we: (i) developed fluorescent probe combinations that distinguish cortical actin from dynamic, pseudopod-forming actin networks, and (ii) adapted molecular visualization tools from structural biology to render and analyze complex cell surfaces. Surprisingly, three-dimensional pseudopods turn out to be composed of thin (<0.75 µm), flat sheets that sometimes interleave to form rosettes. Their laminar nature is not templated by an external surface, but likely reflects a linear arrangement of regulatory molecules. Although we find that Arp2/3-dependent pseudopods are dispensable for three-dimensional locomotion, their elimination dramatically decreases the frequency of cell turning, and pseudopod dynamics increase when cells change direction, highlighting the important role pseudopods play in pathfinding.
Collapse
Affiliation(s)
- Lillian K Fritz-Laylin
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Megan Riel-Mehan
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United States
| | - Bi-Chang Chen
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - Samuel J Lord
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| | - Thomas D Goddard
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
| | - Thomas E Ferrin
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, United States
| | - Susan M Nicholson-Dykstra
- Department of Biochemistry and Cell Biology, Dartmouth Geisel School of Medicine, Hanover, United States
| | - Henry Higgs
- Department of Biochemistry and Cell Biology, Dartmouth Geisel School of Medicine, Hanover, United States
| | - Graham T Johnson
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, San Francisco, United States.,Animated Cell, Allen Institute for Cell Science, Seattle, United States
| | - Eric Betzig
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
| | - R Dyche Mullins
- Department of Cellular and Molecular Pharmacology, Howard Hughes Medical Institute, University of California, San Francisco, San Francisco, United States
| |
Collapse
|
52
|
Farahnak S, McGovern TK, Kim R, O'Sullivan M, Chen B, Lee M, Yoshie H, Wang A, Jang J, Al Heialy S, Lauzon AM, Martin JG. Basic Fibroblast Growth Factor 2 Is a Determinant of CD4 T Cell-Airway Smooth Muscle Cell Communication through Membrane Conduits. THE JOURNAL OF IMMUNOLOGY 2017; 199:3086-3093. [PMID: 28924004 DOI: 10.4049/jimmunol.1700164] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 08/24/2017] [Indexed: 01/23/2023]
Abstract
Activated CD4 T cells connect to airway smooth muscle cells (ASMCs) in vitro via lymphocyte-derived membrane conduits (LMCs) structurally similar to membrane nanotubes with unknown intercellular signals triggering their formation. We examined the structure and function of CD4 T cell-derived LMCs, and we established a role for ASMC-derived basic fibroblast growth factor 2 (FGF2b) and FGF receptor (FGFR)1 in LMC formation. Blocking FGF2b's synthesis and FGFR1 function reduced LMC formation. Mitochondrial flux from ASMCs to T cells was partially FGF2b and FGFR1 dependent. LMC formation by CD4 T cells and mitochondrial transfer from ASMCs was increased in the presence of asthmatic ASMCs that expressed more mRNA for FGF2b compared with normal ASMCs. These observations identify ASMC-derived FGF2b as a factor needed for LMC formation by CD4 T cells, affecting intercellular communication.
Collapse
Affiliation(s)
- Soroor Farahnak
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and.,Department of Medicine, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - Toby K McGovern
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Rachael Kim
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Michael O'Sullivan
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Brian Chen
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Minhyoung Lee
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Haruka Yoshie
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Anna Wang
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Joyce Jang
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Saba Al Heialy
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and
| | - Anne-Marie Lauzon
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and.,Department of Medicine, McGill University, Montreal, Quebec H4A 3J1, Canada
| | - James G Martin
- Meakins-Christie Laboratories, Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre, Montreal, Quebec H4A 3J1, Canada; and .,Department of Medicine, McGill University, Montreal, Quebec H4A 3J1, Canada
| |
Collapse
|
53
|
Abstract
T lymphocytes use surface [Formula: see text] T-cell receptors (TCRs) to recognize peptides bound to MHC molecules (pMHCs) on antigen-presenting cells (APCs). How the exquisite specificity of high-avidity T cells is achieved is unknown but essential, given the paucity of foreign pMHC ligands relative to the ubiquitous self-pMHC array on an APC. Using optical traps, we determine physicochemical triggering thresholds based on load and force direction. Strikingly, chemical thresholds in the absence of external load require orders of magnitude higher pMHC numbers than observed physiologically. In contrast, force applied in the shear direction ([Formula: see text]10 pN per TCR molecule) triggers T-cell Ca2+ flux with as few as two pMHC molecules at the interacting surface interface with rapid positional relaxation associated with similarly directed motor-dependent transport via [Formula: see text]8-nm steps, behaviors inconsistent with serial engagement during initial TCR triggering. These synergistic directional forces generated during cell motility are essential for adaptive T-cell immunity against infectious pathogens and cancers.
Collapse
|
54
|
Stone MB, Shelby SA, Veatch SL. Super-Resolution Microscopy: Shedding Light on the Cellular Plasma Membrane. Chem Rev 2017; 117:7457-7477. [PMID: 28211677 PMCID: PMC5471115 DOI: 10.1021/acs.chemrev.6b00716] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Lipids and the membranes they form are fundamental building blocks of cellular life, and their geometry and chemical properties distinguish membranes from other cellular environments. Collective processes occurring within membranes strongly impact cellular behavior and biochemistry, and understanding these processes presents unique challenges due to the often complex and myriad interactions between membrane components. Super-resolution microscopy offers a significant gain in resolution over traditional optical microscopy, enabling the localization of individual molecules even in densely labeled samples and in cellular and tissue environments. These microscopy techniques have been used to examine the organization and dynamics of plasma membrane components, providing insight into the fundamental interactions that determine membrane functions. Here, we broadly introduce the structure and organization of the mammalian plasma membrane and review recent applications of super-resolution microscopy to the study of membranes. We then highlight some inherent challenges faced when using super-resolution microscopy to study membranes, and we discuss recent technical advancements that promise further improvements to super-resolution microscopy and its application to the plasma membrane.
Collapse
Affiliation(s)
- Matthew B Stone
- Biophysics, University of Michigan, Chemistry 930 N University Ave, Ann Arbor 48109
| | - Sarah A Shelby
- Biophysics, University of Michigan, Chemistry 930 N University Ave, Ann Arbor 48109
| | - Sarah L Veatch
- Biophysics, University of Michigan, Chemistry 930 N University Ave, Ann Arbor 48109
| |
Collapse
|
55
|
Mapping cell surface adhesion by rotation tracking and adhesion footprinting. Sci Rep 2017; 7:44502. [PMID: 28290531 PMCID: PMC5349612 DOI: 10.1038/srep44502] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 02/08/2017] [Indexed: 12/22/2022] Open
Abstract
Rolling adhesion, in which cells passively roll along surfaces under shear flow, is a critical process involved in inflammatory responses and cancer metastasis. Surface adhesion properties regulated by adhesion receptors and membrane tethers are critical in understanding cell rolling behavior. Locally, adhesion molecules are distributed at the tips of membrane tethers. However, how functional adhesion properties are globally distributed on the individual cell’s surface is unknown. Here, we developed a label-free technique to determine the spatial distribution of adhesive properties on rolling cell surfaces. Using dark-field imaging and particle tracking, we extract the rotational motion of individual rolling cells. The rotational information allows us to construct an adhesion map along the contact circumference of a single cell. To complement this approach, we also developed a fluorescent adhesion footprint assay to record the molecular adhesion events from cell rolling. Applying the combination of the two methods on human promyelocytic leukemia cells, our results surprisingly reveal that adhesion is non-uniformly distributed in patches on the cell surfaces. Our label-free adhesion mapping methods are applicable to the variety of cell types that undergo rolling adhesion and provide a quantitative picture of cell surface adhesion at the functional and molecular level.
Collapse
|
56
|
Zheng JY, Tan HL, Matsudaira PT, Choo A. Excess reactive oxygen species production mediates monoclonal antibody-induced human embryonic stem cell death via oncosis. Cell Death Differ 2017; 24:546-558. [PMID: 28106884 DOI: 10.1038/cdd.2016.164] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 11/03/2016] [Accepted: 11/25/2016] [Indexed: 12/29/2022] Open
Abstract
Antibody-mediated cell killing has significantly facilitated the elimination of undesired cells in therapeutic applications. Besides the well-known Fc-dependent mechanisms, pathways of antibody-induced apoptosis were also extensively studied. However, with fewer studies reporting the ability of antibodies to evoke an alternative form of programmed cell death, oncosis, the molecular mechanism of antibody-mediated oncosis remains underinvestigated. In this study, a monoclonal antibody (mAb), TAG-A1 (A1), was generated to selectively kill residual undifferentiated human embryonic stem cells (hESC) so as to prevent teratoma formation upon transplantation of hESC-derived products. We revealed that A1 induces hESC death via oncosis. Aided with high-resolution scanning electron microscopy (SEM), we uncovered nanoscale morphological changes in A1-induced hESC oncosis, as well as A1 distribution on hESC surface. A1 induces hESC oncosis via binding-initiated signaling cascade, most likely by ligating receptors on surface microvilli. The ability to evoke excess reactive oxygen species (ROS) production via the Nox2 isoform of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is critical in the cell death pathway. Excess ROS production occurs downstream of microvilli degradation and homotypic adhesion, but upstream of actin reorganization, plasma membrane damage and mitochondrial membrane permeabilization. To our knowledge, this is the first mechanistic model of mAb-induced oncosis on hESC revealing a previously unrecognized role for NAPDH oxidase-derived ROS in mediating oncotic hESC death. These findings in the cell death pathway may potentially be exploited to improve the efficiency of A1 in eliminating undifferentiated hESC and to provide insights into the study of other mAb-induced cell death.
Collapse
Affiliation(s)
- Ji Yun Zheng
- Mechanobiology Institute (MBI), National University of Singapore (NUS), T-Lab, No. 10-01, 5A Engineering Drive 1, Singapore 117411, Singapore
| | - Heng Liang Tan
- Stem Cell 1 Group, Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, No. 06-01 Centros, Singapore 138668, Singapore
| | - Paul Thomas Matsudaira
- Mechanobiology Institute (MBI), National University of Singapore (NUS), T-Lab, No. 10-01, 5A Engineering Drive 1, Singapore 117411, Singapore.,Department of Biological Science, Faculty of Science, National University of Singapore (NUS), 14 Science Drive 4, Singapore 117543, Singapore
| | - Andre Choo
- Stem Cell 1 Group, Bioprocessing Technology Institute (BTI), Agency for Science, Technology and Research (A*STAR), 20 Biopolis Way, No. 06-01 Centros, Singapore 138668, Singapore.,Department of Biomedical Engineering, Faculty of Engineering, National University of Singapore (NUS), 9 Engineering Drive 1, Singapore 117575, Singapore
| |
Collapse
|
57
|
Improved Measurement of Elastic Properties of Cells by Micropipette Aspiration and Its Application to Lymphocytes. Ann Biomed Eng 2017; 45:1375-1385. [DOI: 10.1007/s10439-017-1795-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 01/10/2017] [Indexed: 10/24/2022]
|
58
|
Jung Y, Riven I, Feigelson SW, Kartvelishvily E, Tohya K, Miyasaka M, Alon R, Haran G. Three-dimensional localization of T-cell receptors in relation to microvilli using a combination of superresolution microscopies. Proc Natl Acad Sci U S A 2016; 113:E5916-E5924. [PMID: 27647916 PMCID: PMC5056101 DOI: 10.1073/pnas.1605399113] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Leukocyte microvilli are flexible projections enriched with adhesion molecules. The role of these cellular projections in the ability of T cells to probe antigen-presenting cells has been elusive. In this study, we probe the spatial relation of microvilli and T-cell receptors (TCRs), the major molecules responsible for antigen recognition on the T-cell membrane. To this end, an effective and robust methodology for mapping membrane protein distribution in relation to the 3D surface structure of cells is introduced, based on two complementary superresolution microscopies. Strikingly, TCRs are found to be highly localized on microvilli, in both peripheral blood human T cells and differentiated effector T cells, and are barely found on the cell body. This is a decisive demonstration that different types of T cells universally localize their TCRs to microvilli, immediately pointing to these surface projections as effective sensors for antigenic moieties. This finding also suggests how previously reported membrane clusters might form, with microvilli serving as anchors for specific T-cell surface molecules.
Collapse
Affiliation(s)
- Yunmin Jung
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Inbal Riven
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Sara W Feigelson
- Department of Immunology, Weizmann Institute of Science, Rehovot 76100, Israel
| | | | - Kazuo Tohya
- Department of Anatomy, Kansai University of Health Sciences, Kumatori, Osaka 590-0482, Japan
| | - Masayuki Miyasaka
- Institute for Academic Initiatives, Osaka University, Suita, Osaka 565-0871, Japan; MediCity Research Laboratory, University of Turku, FI-20521, Turku, Finland
| | - Ronen Alon
- Department of Immunology, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Gilad Haran
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot 76100, Israel;
| |
Collapse
|
59
|
Li M, Xiao X, Liu L, Xi N, Wang Y. Nanoscale Quantifying the Effects of Targeted Drug on Chemotherapy in Lymphoma Treatment Using Atomic Force Microscopy. IEEE Trans Biomed Eng 2016; 63:2187-99. [DOI: 10.1109/tbme.2015.2512924] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
60
|
Guillou L, Babataheri A, Saitakis M, Bohineust A, Dogniaux S, Hivroz C, Barakat AI, Husson J. T-lymphocyte passive deformation is controlled by unfolding of membrane surface reservoirs. Mol Biol Cell 2016; 27:3574-3582. [PMID: 27605708 PMCID: PMC5221589 DOI: 10.1091/mbc.e16-06-0414] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 09/02/2016] [Indexed: 01/03/2023] Open
Abstract
T-lymphocyte passive deformation when squeezing through narrow capillaries is limited by the excess membrane contained in microvilli and membrane folds. During active processes such as transendothelial migration, larger deformations are made possible by an increase in membrane area, possibly through recruitment of internal membrane reservoirs. T-lymphocytes in the human body routinely undergo large deformations, both passively, when going through narrow capillaries, and actively, when transmigrating across endothelial cells or squeezing through tissue. We investigate physical factors that enable and limit such deformations and explore how passive and active deformations may differ. Employing micropipette aspiration to mimic squeezing through narrow capillaries, we find that T-lymphocytes maintain a constant volume while they increase their apparent membrane surface area upon aspiration. Human resting T-lymphocytes, T-lymphoblasts, and the leukemic Jurkat T-cells all exhibit membrane rupture above a critical membrane area expansion that is independent of either micropipette size or aspiration pressure. The unfolded membrane matches the excess membrane contained in microvilli and membrane folds, as determined using scanning electron microscopy. In contrast, during transendothelial migration, a form of active deformation, we find that the membrane surface exceeds by a factor of two the amount of membrane stored in microvilli and folds. These results suggest that internal membrane reservoirs need to be recruited, possibly through exocytosis, for large active deformations to occur.
Collapse
Affiliation(s)
- Lionel Guillou
- Laboratoire d'Hydrodynamique, Ecole Polytechnique, CNRS UMR 7646, 91128 Palaiseau, France
| | - Avin Babataheri
- Laboratoire d'Hydrodynamique, Ecole Polytechnique, CNRS UMR 7646, 91128 Palaiseau, France
| | - Michael Saitakis
- Institut Curie, INSERM U932, PSL Research University, F-75005 Paris, France
| | - Armelle Bohineust
- Institut Curie, INSERM U932, PSL Research University, F-75005 Paris, France.,Institut Pasteur, INSERM U668, Dynamics of Immune Responses Unit, 75015 Paris, France
| | - Stéphanie Dogniaux
- Institut Curie, INSERM U932, PSL Research University, F-75005 Paris, France
| | - Claire Hivroz
- Institut Curie, INSERM U932, PSL Research University, F-75005 Paris, France
| | - Abdul I Barakat
- Laboratoire d'Hydrodynamique, Ecole Polytechnique, CNRS UMR 7646, 91128 Palaiseau, France
| | - Julien Husson
- Laboratoire d'Hydrodynamique, Ecole Polytechnique, CNRS UMR 7646, 91128 Palaiseau, France
| |
Collapse
|
61
|
Hu J, Gondarenko AA, Dang AP, Bashour KT, O’Connor RS, Lee S, Liapis A, Ghassemi S, Milone MC, Sheetz MP, Dustin ML, Kam LC, Hone JC. High-Throughput Mechanobiology Screening Platform Using Micro- and Nanotopography. NANO LETTERS 2016; 16:2198-204. [PMID: 26990380 PMCID: PMC5403373 DOI: 10.1021/acs.nanolett.5b04364] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We herein demonstrate the first 96-well plate platform to screen effects of micro- and nanotopographies on cell growth and proliferation. Existing high-throughput platforms test a limited number of factors and are not fully compatible with multiple types of testing and assays. This platform is compatible with high-throughput liquid handling, high-resolution imaging, and all multiwell plate-based instrumentation. We use the platform to screen for topographies and drug-topography combinations that have short- and long-term effects on T cell activation and proliferation. We coated nanofabricated "trench-grid" surfaces with anti-CD3 and anti-CD28 antibodies to activate T cells and assayed for interleukin 2 (IL-2) cytokine production. IL-2 secretion was enhanced at 200 nm trench width and >2.3 μm grating pitch; however, the secretion was suppressed at 100 nm width and <0.5 μm pitch. The enhancement on 200 nm grid trench was further amplified with the addition of blebbistatin to reduce contractility. The 200 nm grid pattern was found to triple the number of T cells in long-term expansion, a result with direct clinical applicability in adoptive immunotherapy.
Collapse
Affiliation(s)
- Junqiang Hu
- Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States
| | - Alexander A. Gondarenko
- Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States
| | - Alex P. Dang
- Department of Biomedical Engineering, Columbia University, New York, New York 10027, United States
| | - Keenan T. Bashour
- Department of Biomedical Engineering, Columbia University, New York, New York 10027, United States
| | - Roddy S. O’Connor
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Sunwoo Lee
- Department of Electrical Engineering, Columbia University, New York, New York 10027, United States
| | - Anastasia Liapis
- Department of Pathology, New York University School of Medicine, New York, New York 10016, United States
| | - Saba Ghassemi
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Michael C. Milone
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Michael P. Sheetz
- Department of Biological Sciences, Columbia University, New York, New York 10027, United States
| | - Michael L. Dustin
- Nuffield Department of Orthopedics, Rheumatology and Musculoskeletal Sciences, Kennedy Institute of Rheumatology, The University of Oxford, Oxford, OX3 7FY, U.K
| | - Lance C. Kam
- Department of Biomedical Engineering, Columbia University, New York, New York 10027, United States
| | - James C. Hone
- Department of Mechanical Engineering, Columbia University, New York, New York 10027, United States
| |
Collapse
|
62
|
Poon CCW, Li RWS, Seto SW, Kong SK, Ho HP, Hoi MPM, Lee SMY, Ngai SM, Chan SW, Leung GPH, Kwan YW. In vitro vitamin K(2) and 1α,25-dihydroxyvitamin D(3) combination enhances osteoblasts anabolism of diabetic mice. Eur J Pharmacol 2015; 767:30-40. [PMID: 26452518 DOI: 10.1016/j.ejphar.2015.09.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 09/25/2015] [Accepted: 09/29/2015] [Indexed: 12/20/2022]
Abstract
In this study, we evaluated the anabolic effect and the underlying cellular mechanisms involved of vitamin K2 (10 nM) and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) (10 nM), alone and in combination, on primary osteoblasts harvested from the iliac crests of C57BL/KsJ lean (+/+) and obese/diabetic (db/db) mice. A lower alkaline phosphatase (ALP) activity plus a reduced expression of bone anabolic markers and bone formation transcription factors (osteocalcin, Runx2, Dlx5, ATF4 and OSX) were consistently detected in osteoblasts of db/db mice compared to lean mice. A significantly higher calcium deposits formation in osteoblasts was observed in lean mice when compared to db/db mice. Co-administration of vitamin K2 (10 nM) and 1,25(OH)2D3 (10 nM) caused an enhancement of calcium deposits in osteoblasts in both strains of mice. Vitamins K2 and 1,25(OH)2D3 co-administration time-dependently (7, 14 and 21 days) increased the levels of bone anabolic markers and bone formation transcription factors, with a greater magnitude of increase observed in osteoblasts of db/db mice. Combined vitamins K2 plus 1,25(OH)2D3 treatment significantly enhanced migration and the re-appearance of surface microvilli and ruffles of osteoblasts of db/db mice. Thus, our results illustrate that vitamins K2 plus D3 combination could be a novel therapeutic strategy in treating diabetes-associated osteoporosis.
Collapse
Affiliation(s)
- Christina C W Poon
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Rachel W S Li
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong; Department of Pharmacology and Pharmacy, Faculty of Medicine, The University of Hong Kong, Hong Kong
| | - Sai Wang Seto
- National Institute of Complementary Medicine, School of Science and Health, University of Western Sydney, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Siu Kai Kong
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Hong Kong
| | - Ho Pui Ho
- Department of Electronic Engineering, Faculty of Engineering, The Chinese University of Hong Kong, Hong Kong
| | - Maggie P M Hoi
- Institute of Chinese Medical Sciences, The University of Macau, Macau, China
| | - Simon M Y Lee
- Institute of Chinese Medical Sciences, The University of Macau, Macau, China
| | - Sai Ming Ngai
- School of Life Sciences, Faculty of Science, The Chinese University of Hong Kong, Hong Kong
| | - Shun Wan Chan
- State Key Laboratory of Chinese Medicine and Molecular Pharmacology, Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong
| | - George P H Leung
- Department of Pharmacology and Pharmacy, Faculty of Medicine, The University of Hong Kong, Hong Kong.
| | - Yiu Wa Kwan
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong.
| |
Collapse
|
63
|
Young LE, Heimsath EG, Higgs HN. Cell type-dependent mechanisms for formin-mediated assembly of filopodia. Mol Biol Cell 2015; 26:4646-59. [PMID: 26446836 PMCID: PMC4678021 DOI: 10.1091/mbc.e15-09-0626] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 10/01/2015] [Indexed: 11/11/2022] Open
Abstract
Filopodia are finger-like protrusions from the plasma membrane and are of fundamental importance to cellular physiology, but the mechanisms governing their assembly are still in question. One model, called convergent elongation, proposes that filopodia arise from Arp2/3 complex-nucleated dendritic actin networks, with factors such as formins elongating these filaments into filopodia. We test this model using constitutively active constructs of two formins, FMNL3 and mDia2. Surprisingly, filopodial assembly requirements differ between suspension and adherent cells. In suspension cells, Arp2/3 complex is required for filopodial assembly through either formin. In contrast, a subset of filopodia remains after Arp2/3 complex inhibition in adherent cells. In adherent cells only, mDia1 and VASP also contribute to filopodial assembly, and filopodia are disproportionately associated with focal adhesions. We propose an extension of the existing models for filopodial assembly in which any cluster of actin filament barbed ends in proximity to the plasma membrane, either Arp2/3 complex dependent or independent, can initiate filopodial assembly by specific formins.
Collapse
Affiliation(s)
- Lorna E Young
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Ernest G Heimsath
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| | - Henry N Higgs
- Department of Biochemistry, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
| |
Collapse
|
64
|
Martinez RJ, Evavold BD. Lower Affinity T Cells are Critical Components and Active Participants of the Immune Response. Front Immunol 2015; 6:468. [PMID: 26441973 PMCID: PMC4564719 DOI: 10.3389/fimmu.2015.00468] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 08/28/2015] [Indexed: 11/13/2022] Open
Abstract
Kinetic and biophysical parameters of T cell receptor (TCR) and peptide:MHC (pMHC) interaction define intrinsic factors required for T cell activation and differentiation. Although receptor ligand kinetics are somewhat cumbersome to assess experimentally, TCR:pMHC affinity has been shown to predict peripheral T cell functionality and potential for forming memory. Multimeric forms of pMHC monomers have often been used to provide an indirect readout of higher affinity T cells due to their availability and ease of use while allowing simultaneous definition of other functional and phenotypic characteristics. However, multimeric pMHC reagents have introduced a bias that underestimates the lower affinity components contained in the highly diverse TCR repertoires of all polyclonal T cell responses. Advances in the identification of lower affinity cells have led to the examination of these cells and their contribution to the immune response. In this review, we discuss the identification of high- vs. low-affinity T cells as well as their attributed signaling and functional differences. Lastly, mechanisms are discussed that maintain a diverse range of low- and high-affinity T cells.
Collapse
Affiliation(s)
- Ryan J. Martinez
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, USA
| | - Brian D. Evavold
- Department of Microbiology and Immunology, Emory University, Atlanta, GA, USA
| |
Collapse
|
65
|
Grega-Larson NE, Crawley SW, Erwin AL, Tyska MJ. Cordon bleu promotes the assembly of brush border microvilli. Mol Biol Cell 2015; 26:3803-15. [PMID: 26354418 PMCID: PMC4626065 DOI: 10.1091/mbc.e15-06-0443] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Accepted: 09/02/2015] [Indexed: 01/24/2023] Open
Abstract
Microvilli are actin-based protrusions that amplify plasma membrane area and mediate interactions with the extracellular environment. We found that the multifunctional actin regulator cordon bleu promotes the growth of intestinal brush border microvilli. These results provide a new framework for investigating brush border biogenesis. Microvilli are actin-based protrusions found on the surface of diverse cell types, where they amplify membrane area and mediate interactions with the external environment. In the intestinal tract, these protrusions play central roles in nutrient absorption and host defense and are therefore essential for maintaining homeostasis. However, the mechanisms controlling microvillar assembly remain poorly understood. Here we report that the multifunctional actin regulator cordon bleu (COBL) promotes the growth of brush border (BB) microvilli. COBL localizes to the base of BB microvilli via a mechanism that requires its proline-rich N-terminus. Knockdown and overexpression studies show that COBL is needed for BB assembly and sufficient to induce microvillar growth using a mechanism that requires functional WH2 domains. We also find that COBL acts downstream of the F-BAR protein syndapin-2, which drives COBL targeting to the apical domain. These results provide insight into a mechanism that regulates microvillar growth during epithelial differentiation and have significant implications for understanding the maintenance of intestinal homeostasis.
Collapse
Affiliation(s)
- Nathan E Grega-Larson
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240
| | - Scott W Crawley
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240
| | - Amanda L Erwin
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37240
| |
Collapse
|
66
|
Abstract
Cell shape is determined by cellular mechanics. Cell deformations in animal cells, such as those required for cell migration, division or epithelial morphogenesis, are largely controlled by changes in mechanical stress and tension at the cell surface. The plasma membrane and the actomyosin cortex control surface mechanics and determine cell surface tension. Tension in the actomyosin cortex primarily arises from myosin-generated stresses and depends strongly on the ultrastructural architecture of the network. Plasma membrane tension is controlled mainly by the surface area of the membrane relative to cell volume and can be modulated by changing membrane composition, shape and the organization of membrane-associated proteins. We review here our current understanding of the control of cortex and membrane tension by molecular processes. We particularly highlight the need for studies that bridge the scales between microscopic events and emergent properties at the cellular level. Finally, we discuss how the mechanical interplay between membrane dynamics and cortex contractility is key to understanding the biomechanical control of cell morphogenesis.
Collapse
|
67
|
Arita-Okubo S, Kim-Kaneyama JR, Lei XF, Fu WG, Ohnishi K, Takeya M, Miyauchi A, Honda H, Itabe H, Miyazaki T, Miyazaki A. Role of Hic-5 in the formation of microvilli-like structures and the monocyte-endothelial interaction that accelerates atherosclerosis. Cardiovasc Res 2015; 105:361-71. [PMID: 25587044 DOI: 10.1093/cvr/cvv003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
AIMS The adhesion of circulating monocytes to endothelial cells (ECs) is an early and critical event in the formation of atherosclerotic plaques. Hydrogen peroxide-inducible clone 5 (Hic-5) serves as an adaptor molecule in cell adhesion complexes. However, the role of endothelial Hic-5 in monocyte-EC interaction and atherogenesis remains unclear. We examined the roles of endothelial Hic-5 in monocyte-EC interaction and atherogenesis using mouse models of atherosclerosis and cultured human umbilical vein endothelial cells (HUVECs). METHODS AND RESULTS Hic-5 was expressed in ECs, but not in monocytes/macrophages. An ex vivo monocyte adhesion assay revealed that adhesion of THP-1 monocytes to aortas isolated from Apoe(-/-) and LDLR(-/-) mice stimulated by TNF-α or oxidized LDL was suppressed by Hic-5 deficiency. Scanning electron microscopic observations of aortas harvested from Apoe(-/-) mice revealed that TNF-α- or oxidized LDL-induced microvilli-like structures were markedly suppressed by Hic-5 deficiency. Relative Hic-5 deficiency suppressed 60% of the atherosclerotic lesions in aortas from Apoe(-/-) and LDLR(-/-) mice. In contrast, overexpression of Hic-5 in HUVECs promoted induction of microvilli-like structures and adherence of THP-1 cells in an adhesion receptor such as intercellular adhesion molecule-1- and vascular cell adhesion molecule-1-dependent manner. CONCLUSION Hic-5 in ECs plays an important role in the formation of microvilli-like structures and in the interaction between ECs and monocytes, leading to monocyte recruitment and subsequent development of atherosclerosis.
Collapse
Affiliation(s)
- Shigeko Arita-Okubo
- Department of Biochemistry, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Joo-Ri Kim-Kaneyama
- Department of Biochemistry, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Xiao-Feng Lei
- Department of Biochemistry, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Wen-Guang Fu
- Department of Biochemistry, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Koji Ohnishi
- Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Motohiro Takeya
- Department of Cell Pathology, Graduate School of Medical Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan
| | - Aya Miyauchi
- Department of Biochemistry, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Hirokazu Honda
- Division of Nephrology, Department of Medicine, Showa University Koto Toyosu Hospital, Tokyo, Japan
| | - Hiroyuki Itabe
- Division of Biological Chemistry, Department of Molecular Biology, Showa University School of Pharmacy, Tokyo, Japan
| | - Takuro Miyazaki
- Department of Biochemistry, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Akira Miyazaki
- Department of Biochemistry, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| |
Collapse
|
68
|
Mi Li, Lianqing Liu, Ning Xi, Yuechao Wang, Xiubin Xiao, Weijing Zhang. Quantitative Analysis of Drug-Induced Complement-Mediated Cytotoxic Effect on Single Tumor Cells Using Atomic Force Microscopy and Fluorescence Microscopy. IEEE Trans Nanobioscience 2015; 14:84-94. [DOI: 10.1109/tnb.2014.2370759] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
69
|
Wang M, Misakian M, He HJ, Bajcsy P, Abbasi F, Davis JM, Cole KD, Turko IV, Wang L. Quantifying CD4 receptor protein in two human CD4+ lymphocyte preparations for quantitative flow cytometry. Clin Proteomics 2014; 11:43. [PMID: 25593565 PMCID: PMC4277840 DOI: 10.1186/1559-0275-11-43] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 11/05/2014] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND In our previous study that characterized different human CD4+ lymphocyte preparations, it was found that both commercially available cryopreserved peripheral blood mononuclear cells (PBMC) and a commercially available lyophilized PBMC (Cyto-Trol™) preparation fulfilled a set of criteria for serving as biological calibrators for quantitative flow cytometry. However, the biomarker CD4 protein expression level measured for T helper cells from Cyto-Trol was about 16% lower than those for cryopreserved PBMC and fresh whole blood using flow cytometry and mass cytometry. A primary reason was hypothesized to be due to steric interference in anti- CD4 antibody binding to the smaller sized lyophilized control cells. METHOD Targeted multiple reaction monitoring (MRM) mass spectrometry (MS) is used to quantify the copy number of CD4 receptor protein per CD4+ lymphocyte. Scanning electron microscopy (SEM) is utilized to assist searching the underlying reasons for the observed difference in CD4 receptor copy number per cell determined by MRM MS and CD4 expression measured previously by flow cytometry. RESULTS The copy number of CD4 receptor proteins on the surface of the CD4+ lymphocyte in cryopreserved PBMCs and in lyophilized control cells is determined to be (1.45 ± 0.09) × 10(5) and (0.85 ± 0.11) × 10(5), respectively, averaged over four signature peptides using MRM MS. In comparison with cryopreserved PBMCs, there are more variations in the CD4 copy number in lyophilized control cells determined based on each signature peptide. SEM images of CD4+ lymphocytes from lyophilized control cells are very different when compared to the CD4+ T cells from whole blood and cryopreserved PBMC. CONCLUSION Because of the lyophilization process applied to Cyto-Trol control cells, a lower CD4 density value, defined as the copy number of CD4 receptors per CD4+ lymphocyte, averaged over three different production lots is most likely explained by the loss of the CD4 receptors on damaged and/or broken microvilli where CD4 receptors reside. Steric hindrance of antibody binding and the association of CD4 receptors with other biomolecules likely contribute significantly to the nearly 50% lower CD4 receptor density value for cryopreserved PBMC determined from flow cytometry compared to the value obtained from MRM MS.
Collapse
Affiliation(s)
- Meiyao Wang
- />Institute for Bioscience and Biotechnology Research, University of Maryland, 9600 Gudelsky Drive, Rockville, MD 20850 USA
- />Biomolecular Measurement Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 USA
| | - Martin Misakian
- />Quantum Measurements Division, NIST, 100 Bureau Drive, Stop 8312, Gaithersburg, MD 20899 USA
| | - Hua-Jun He
- />Biosystems and Biomaterials Division, NIST, 100 Bureau Drive, Stop 8312, Gaithersburg, MD 20899 USA
| | - Peter Bajcsy
- />Software and Systems Division, NIST, 100 Bureau Drive, Stop 8312, Gaithersburg, MD 20899 USA
| | - Fatima Abbasi
- />Laboratory of Stem Cell Biology, Cellular and Tissue Therapy Branch, Division of Cell and Gene Therapies, CBER FDA, 8800 Rockville Pike, Bethesda, MD 20892 USA
| | - Jeffrey M Davis
- />Materials Measurement Science Division, NIST, 100 Bureau Drive, Stop 8312, Gaithersburg, MD 20899 USA
| | - Kenneth D Cole
- />Biosystems and Biomaterials Division, NIST, 100 Bureau Drive, Stop 8312, Gaithersburg, MD 20899 USA
| | - Illarion V Turko
- />Institute for Bioscience and Biotechnology Research, University of Maryland, 9600 Gudelsky Drive, Rockville, MD 20850 USA
- />Biomolecular Measurement Division, National Institute of Standards and Technology (NIST), Gaithersburg, MD 20899 USA
| | - Lili Wang
- />Biosystems and Biomaterials Division, NIST, 100 Bureau Drive, Stop 8312, Gaithersburg, MD 20899 USA
| |
Collapse
|
70
|
Meng J, Liu H, Liu X, Yang G, Zhang P, Wang S, Jiang L. Hierarchical biointerfaces assembled by leukocyte-inspired particles for specifically recognizing cancer cells. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:3735-3741. [PMID: 24839236 DOI: 10.1002/smll.201400215] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Indexed: 06/03/2023]
Abstract
By mimicking certain biochemical and physical attributes of biological cells, bio-inspired particles have attracted great attention for potential biomedical applications based on cell-like biological functions. Inspired by leukocytes, hierarchical biointerfaces are designed and prepared based on specific molecules-modified leukocyte-inspired particles. These biointerfaces can efficiently recognize cancer cells from whole blood samples through the synergistic effect of molecular recognition and topographical interaction. Compared to flat, mono-micro or nano-biointerfaces, these micro/nano hierarchical biointerfaces are better able to promote specific recognition interactions, resulting in an enhanced cell-capture efficiency. It is anticipated that this study may provide promising guidance to develop new bio-inspired hierarchical biointerfaces for biomedical applications.
Collapse
Affiliation(s)
- Jingxin Meng
- Laboratory of Bio-inspired Smart Interface Science, Technical Institute of Physics and Chemistry, Chinese Academy of Science, Beijing, 100190, P. R. China
| | | | | | | | | | | | | |
Collapse
|
71
|
Liu B, Chen W, Evavold BD, Zhu C. Accumulation of dynamic catch bonds between TCR and agonist peptide-MHC triggers T cell signaling. Cell 2014; 157:357-368. [PMID: 24725404 DOI: 10.1016/j.cell.2014.02.053] [Citation(s) in RCA: 411] [Impact Index Per Article: 41.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 09/27/2013] [Accepted: 02/21/2014] [Indexed: 10/25/2022]
Abstract
TCR-pMHC interactions initiate adaptive immune responses, but the mechanism of how such interactions under force induce T cell signaling is unclear. We show that force prolongs lifetimes of single TCR-pMHC bonds for agonists (catch bonds) but shortens those for antagonists (slip bonds). Both magnitude and duration of force are important, as the highest Ca(2+) responses were induced by 10 pN via both pMHC catch bonds whose lifetime peaks at this force and anti-TCR slip bonds whose maximum lifetime occurs at 0 pN. High Ca(2+) levels require early and rapid accumulation of bond lifetimes, whereas short-lived bonds that slow early accumulation of lifetimes correspond to low Ca(2+) responses. Our data support a model in which force on the TCR induces signaling events depending on its magnitude, duration, frequency, and timing, such that agonists form catch bonds that trigger the T cell digitally, whereas antagonists form slip bonds that fail to activate.
Collapse
Affiliation(s)
- Baoyu Liu
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Wei Chen
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | - Brian D Evavold
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Cheng Zhu
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA; Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA 30332, USA.
| |
Collapse
|
72
|
Pryshchep S, Zarnitsyna VI, Hong J, Evavold BD, Zhu C. Accumulation of serial forces on TCR and CD8 frequently applied by agonist antigenic peptides embedded in MHC molecules triggers calcium in T cells. THE JOURNAL OF IMMUNOLOGY 2014; 193:68-76. [PMID: 24890718 DOI: 10.4049/jimmunol.1303436] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
T cell activation by Ag is one of the key events in adaptive immunity. It is triggered by interactions of the TCR and coreceptor (CD8 or CD4) with antigenic peptides embedded in MHC (pMHC) molecules expressed on APCs. The mechanism of how signal is initiated remains unclear. In this article, we complement our two-dimensional kinetic analysis of TCR-pMHC-CD8 interaction with concurrent calcium imaging to examine how ligand engagement of TCR with and without the coengagement of CD8 initiates signaling. We found that accumulation of frequently applied forces on the TCR via agonist pMHC triggered calcium, which was further enhanced by CD8 cooperative binding. Prolonging the intermission between sequential force applications impaired calcium signals. Our data support a model where rapid accumulation of serial forces on TCR-pMHC-CD8 bonds triggers calcium in T cells.
Collapse
Affiliation(s)
- Sergey Pryshchep
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332
| | - Veronika I Zarnitsyna
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332
| | - Jinsung Hong
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332; and
| | - Brian D Evavold
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30322
| | - Cheng Zhu
- Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA 30332; Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332; and
| |
Collapse
|
73
|
Abstract
The importance of the cytoskeleton in mounting a successful immune response is evident from the wide range of defects that occur in actin-related primary immunodeficiencies (PIDs). Studies of these PIDs have revealed a pivotal role for the actin cytoskeleton in almost all stages of immune system function, from hematopoiesis and immune cell development, through to recruitment, migration, intercellular and intracellular signaling, and activation of both innate and adaptive immune responses. The major focus of this review is the immune defects that result from mutations in the Wiskott-Aldrich syndrome gene (WAS), which have a broad impact on many different processes and give rise to clinically heterogeneous immunodeficiencies. We also discuss other related genetic defects and the possibility of identifying new genetic causes of cytoskeletal immunodeficiency.
Collapse
Affiliation(s)
- Dale A Moulding
- Molecular Immunology Unit, Center for Immunodeficiency, Institute of Child Health, University College London, London, UK
| | | | | | | |
Collapse
|
74
|
Sackmann E, Smith AS. Physics of cell adhesion: some lessons from cell-mimetic systems. SOFT MATTER 2014; 10:1644-59. [PMID: 24651316 PMCID: PMC4028615 DOI: 10.1039/c3sm51910d] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Cell adhesion is a paradigm of the ubiquitous interplay of cell signalling, modulation of material properties and biological functions of cells. It is controlled by competition of short range attractive forces, medium range repellant forces and the elastic stresses associated with local and global deformation of the composite cell envelopes. We review the basic physical rules governing the physics of cell adhesion learned by studying cell-mimetic systems and demonstrate the importance of these rules in the context of cellular systems. We review how adhesion induced micro-domains couple to the intracellular actin and microtubule networks allowing cells to generate strong forces with a minimum of attractive cell adhesion molecules (CAMs) and to manipulate other cells through filopodia over micrometer distances. The adhesion strength can be adapted to external force fluctuations within seconds by varying the density of attractive and repellant CAMs through exocytosis and endocytosis or protease-mediated dismantling of the CAM-cytoskeleton link. Adhesion domains form local end global biochemical reaction centres enabling the control of enzymes. Actin-microtubule crosstalk at adhesion foci facilitates the mechanical stabilization of polarized cell shapes. Axon growth in tissue is guided by attractive and repulsive clues controlled by antagonistic signalling pathways.
Collapse
Affiliation(s)
- Erich Sackmann
- Physics Department Technical University Munich, Germany
- Department of Physics, Ludwig-Maximillian University, Munich, Germany
| | - Ana-Sunčana Smith
- Institute for Theoretical Physics, Friedrich Alexander University Erlangen-Nürnberg, Erlangen, Germany
- Institute Rud̷er Bošković, Zagreb, Croatia.
| |
Collapse
|
75
|
Monitoring actin cortex thickness in live cells. Biophys J 2014; 105:570-80. [PMID: 23931305 DOI: 10.1016/j.bpj.2013.05.057] [Citation(s) in RCA: 158] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Revised: 05/07/2013] [Accepted: 05/24/2013] [Indexed: 01/07/2023] Open
Abstract
Animal cell shape is controlled primarily by the actomyosin cortex, a thin cytoskeletal network that lies directly beneath the plasma membrane. The cortex regulates cell morphology by controlling cellular mechanical properties, which are determined by network structure and geometry. In particular, cortex thickness is expected to influence cell mechanics. However, cortex thickness is near the resolution limit of the light microscope, making studies relating cortex thickness and cell shape challenging. To overcome this, we developed an assay to measure cortex thickness in live cells, combining confocal imaging and subresolution image analysis. We labeled the actin cortex and plasma membrane with chromatically different fluorophores and measured the distance between the resulting intensity peaks. Using a theoretical description of cortex geometry and microscopic imaging, we extracted an average cortex thickness of ∼190 nm in mitotic HeLa cells and tested the validity of our assay using cell images generated in silico. We found that thickness increased after experimental treatments preventing F-actin disassembly. Finally, we monitored physiological changes in cortex thickness in real-time during actin cortex regrowth in cellular blebs. Our investigation paves the way to understanding how molecular processes modulate cortex structure, which in turn drives cell morphogenesis.
Collapse
|
76
|
Hutchinson CV, Natarajan S, Johnson SM, Adams JA, Rees-Unwin KS, Burthem J. Lymphocytes from chronic lymphocytic leukaemia undergo ABL1-linked amoeboid motility and homotypic interaction as an early adaptive change to ex vivo culture. Exp Hematol Oncol 2014; 3:7. [PMID: 24618035 PMCID: PMC3995717 DOI: 10.1186/2162-3619-3-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Accepted: 02/19/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Those stimuli that together promote the survival, differentiation and proliferation of the abnormal B-lymphocytes of chronic lymphocytic leukaemia (CLL) are encountered within tissues, where together they form the growth-supporting microenvironment. Different tissue-culture systems promote the survival of the neoplastic lymphocytes from CLL, partly replicating the in vivo tissue environment of the disorder. In the present study, we focussed on the initial adaptive changes to the tissue culture environment focussing particularly on migratory behaviour and cellular interactions. METHODS A high-density CLL culture system was employed to test CLL cell-responses using a range of microscopic techniques and flow cytometric analyses, supported by mathematical measures of cell shape-change and by biochemical techniques. The study focussed on the evaluation of changes to the F-actin cytoskeleton and cell behaviour and on ABL1 signalling processes. RESULTS We showed that the earliest functional response by the neoplastic lymphocytes was a rapid shape-change caused through rearrangement of the F-actin cytoskeleton that resulted in amoeboid motility and promoted frequent homotypic interaction between cells. This initial response was functionally distinct from the elongated motility that was induced by chemokine stimulation, and which also characterised heterotypic interactions between CLL lymphocytes and accessory cells at later culture periods. ABL1 is highly expressed in CLL lymphocytes and supports their survival, it is also recognised however to have a major role in the control of the F-actin cytoskeleton. We found that the cytoplasmic fraction of ABL1 became co-localised with F-actin structures of the CLL lymphocytes and that the ABL1 substrate CRKL became phosphorylated during initial shape-change. The ABL-inhibitor imatinib mesylate prevented amoeboid movement and markedly reduced homotypic interactions, causing cells to acquire a globular shape to rearrange F-actin to a microvillus form that closely resembled that of CLL cells isolated directly from circulation. CONCLUSION We suggest that ABL1-induced amoeboid motility and homotypic interaction represent a distinctive early response to the tissue environment by CLL lymphocytes. This response is separate from that induced by chemokine or during heterotypic cell-contact, and may play a role in the initial entry and interactions of CLL lymphocytes in tissues.
Collapse
Affiliation(s)
- Claire V Hutchinson
- Institute of Cancer Sciences, Haematological Oncology, University of Manchester, Level 5 Research St. Mary’s Hospital, Oxford Road, Manchester M13 9WL, UK
| | - Shiva Natarajan
- Institute of Cancer Sciences, Haematological Oncology, University of Manchester, Level 5 Research St. Mary’s Hospital, Oxford Road, Manchester M13 9WL, UK
| | - Suzanne M Johnson
- Institute of Cancer Sciences, Manchester Academic Health Science Centre, The Christie NHS Foundation Trust, 550 Wilmslow Rd, Manchester M20 4BX, UK
| | - Julie A Adams
- Clinical Haematology, Central Manchester University Hospitals, Oxford Road, Manchester M13 9WL, UK
| | - Karen S Rees-Unwin
- Institute of Cancer Sciences, Haematological Oncology, University of Manchester, Level 5 Research St. Mary’s Hospital, Oxford Road, Manchester M13 9WL, UK
| | - John Burthem
- Institute of Cancer Sciences, Haematological Oncology, University of Manchester, Level 5 Research St. Mary’s Hospital, Oxford Road, Manchester M13 9WL, UK
- Clinical Haematology, Central Manchester University Hospitals, Oxford Road, Manchester M13 9WL, UK
| |
Collapse
|
77
|
Dynamics of adhesion molecule domains on neutrophil membranes: surfing the dynamic cell topography. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2013; 42:851-5. [PMID: 24113789 DOI: 10.1007/s00249-013-0931-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2013] [Revised: 08/22/2013] [Accepted: 09/17/2013] [Indexed: 10/26/2022]
Abstract
Lateral organization and mobility of adhesion molecules play a significant role in determining the avidity with which cells can bind to target cells or surfaces. Recently, we have shown that the lateral mobility of the principal adhesion molecules on neutrophils is lower for rolling associated adhesion molecules (RAAMs: L-selectin and PSGL-1) than for β2 integrins (LFA-1 and Mac-1). Here we report that all four adhesion molecules exhibit distinct punctate distributions that are mobile on the cell surface. Using uniform illumination image correlation microscopy, we measure the lateral mobility of these topologically distinct domains. For all four molecules, we find that diffusion coefficients calculated from domain mobility agree with measurements we made previously using fluorescence recovery after photobleaching. This agreement indicates that the transport of receptors on the surface of the resting neutrophil is dominated by the lateral movement of domains rather than individual molecules. The diffusion of pre-assembled integrin domains to zones of neutrophil/endothelial contact may provide a mechanism to facilitate high avidity adhesion during the earliest stages of firm arrest.
Collapse
|
78
|
Platzman I, Janiesch JW, Spatz JP. Synthesis of nanostructured and biofunctionalized water-in-oil droplets as tools for homing T cells. J Am Chem Soc 2013; 135:3339-42. [PMID: 23419177 PMCID: PMC3806295 DOI: 10.1021/ja311588c] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Indexed: 12/16/2022]
Abstract
Activation, ex vivo expansion of T cells, differentiation into a regulatory subset, and its phenotype-specific high-throughput selection represent major challenges in immunobiology. In part, this is due to the lack of technical means to synthesize suitable 3D extracellular systems to imitate ex vivo the cellular interactions between T cells and antigen-presenting cells (APCs). In this study, we synthesized a new type of gold-linked surfactant and used a drop-based microfluidic device to develop and characterize novel nanostructured and specifically biofunctionalized droplets of water-in-oil emulsions as 3D APC analogues. Combining flexible biofunctionalization with the pliable physical properties of the nanostructured droplets provided this system with superior properties in comparison with previously reported synthetic APC analogues.
Collapse
Affiliation(s)
| | | | - Joachim Pius Spatz
- Department of New
Materials and Biosystems, Max Planck Institute for Intelligent
Systems, Heisenbergstr.
3, 70569 Stuttgart, Germany, and Department of Biophysical Chemistry, University of Heidelberg, 69120 Heidelberg, Germany
| |
Collapse
|
79
|
Maus M, Medgyesi D, Kiss E, Schneider AE, Enyedi A, Szilágyi N, Matkó J, Sármay G. B cell receptor-induced Ca2+ mobilization mediates F-actin rearrangements and is indispensable for adhesion and spreading of B lymphocytes. J Leukoc Biol 2013; 93:537-47. [PMID: 23362305 DOI: 10.1189/jlb.0312169] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
B cells acquire membrane-bound cognate antigens from the surface of the APCs by forming an IS, similar to that seen in T cells. Recognition of membrane-bound antigens on the APCs initiates adhesion of B lymphocytes to the antigen-tethered surface, which is followed by the formation of radial lamellipodia-like structures, a process known as B cell spreading. The spreading response requires the rearrangement of the submembrane actin cytoskeleton and is regulated mainly via signals transmitted by the BCR. Here, we show that cytoplasmic calcium is a regulator of actin cytoskeleton dynamics in B lymphocytes. We find that BCR-induced calcium mobilization is indispensible for adhesion and spreading of B cells and that PLCγ and CRAC-mediated calcium mobilization are critical regulators of these processes. Measuring calcium and actin dynamics in live cells, we found that a generation of actin-based membrane protrusion is strongly linked to the dynamics of a cytoplasmic-free calcium level. Finally, we demonstrate that PLCγ and CRAC channels regulate the activity of actin-severing protein cofilin, linking BCR-induced calcium signaling to the actin dynamics.
Collapse
Affiliation(s)
- Máté Maus
- Eötvös Lóránd University, Pázmány Péter sétány 1/c, Budapest, Hungary
| | | | | | | | | | | | | | | |
Collapse
|
80
|
Khismatullin DB, Truskey GA. Leukocyte rolling on P-selectin: a three-dimensional numerical study of the effect of cytoplasmic viscosity. Biophys J 2012; 102:1757-66. [PMID: 22768931 DOI: 10.1016/j.bpj.2012.03.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 02/12/2012] [Accepted: 03/02/2012] [Indexed: 01/23/2023] Open
Abstract
Rolling leukocytes deform and show a large area of contact with endothelium under physiological flow conditions. We studied the effect of cytoplasmic viscosity on leukocyte rolling using our three-dimensional numerical algorithm that treats leukocyte as a compound droplet in which the core phase (nucleus) and the shell phase (cytoplasm) are viscoelastic fluids. The algorithm includes the mechanical properties of the cell cortex by cortical tension and considers leukocyte microvilli that deform viscoelastically and form viscous tethers at supercritical force. Stochastic binding kinetics describes binding of adhesion molecules. The leukocyte cytoplasmic viscosity plays a critical role in leukocyte rolling on an adhesive substrate. High-viscosity cells are characterized by high mean rolling velocities, increased temporal fluctuations in the instantaneous velocity, and a high probability for detachment from the substrate. A decrease in the rolling velocity, drag, and torque with the formation of a large, flat contact area in low-viscosity cells leads to a dramatic decrease in the bond force and stable rolling. Using values of viscosity consistent with step aspiration studies of human neutrophils (5-30 Pa·s), our computational model predicts the velocities and shape changes of rolling leukocytes as observed in vitro and in vivo.
Collapse
Affiliation(s)
- Damir B Khismatullin
- Department of Biomedical Engineering and Center for Computational Science, Tulane University, New Orleans, Louisiana, USA.
| | | |
Collapse
|
81
|
Abstract
The Rif GTPase is a recent addition to small Rho GTPase family; it shares low homology with other members in the family and evolutionarily parallels with the development of vertebrates. Rif has the conserved Rho GTPase domain structures and cycles between a GDP-bound inactive form and a GTP-bound active form. In its active form, Rif signals through multiple downstream effectors. In the present review, our aim is to summarize the current information about the Rif effectors and how Rif remodels actin cytoskeleton in many aspects.
Collapse
|
82
|
Shulman Z, Alon R. Real-time analysis of integrin-dependent transendothelial migration and integrin-independent interstitial motility of leukocytes. Methods Mol Biol 2012; 757:31-45. [PMID: 21909904 DOI: 10.1007/978-1-61779-166-6_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The role of integrins in leukocyte migration across endothelial barriers is widely accepted. In contrast, the contribution of integrins to interstitial motility of leukocytes is still elusive. Chemokine binding to G-protein-coupled receptors expressed on the surface of leukocytes plays key roles in both of these processes by directly activating integrin conformations favorable for ligand binding and integrin microclustering. Chemokines can also serve as weak adhesive ligands and potent inducers of actin cytoskeleton remodeling. Real-time assays utilizing live imaging microscopy have been implemented to dissect these versatile roles of chemokines in different leukocyte migration processes. Here, we review several in vitro assays useful for exploring the contribution of chemokine signals and shear forces to integrin activation and function during various stages of leukocyte transendothelial migration. In addition, we describe a new assay that assesses the contribution of chemokines to integrin-independent interstitial leukocyte motility. These assays can also follow the outcome of specific genetic or biochemical manipulations of either the leukocyte or the endothelial barrier on distinct migratory steps. Following fixation, subcellular changes in the distribution of integrin subsets and of specific integrin-associated adaptors can be further dissected by immunofluorescence tools and by ultrastructural electron microscopic analysis.
Collapse
Affiliation(s)
- Ziv Shulman
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
| | | |
Collapse
|
83
|
Khatibzadeh N, Gupta S, Farrell B, Brownell WE, Anvari B. Effects of cholesterol on nano-mechanical properties of the living cell plasma membrane. SOFT MATTER 2012; 8:8350-8360. [PMID: 23227105 PMCID: PMC3515074 DOI: 10.1039/c2sm25263e] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
In this study, we investigated the effects of membrane cholesterol content on the mechanical properties of cell membranes by using optical tweezers. We pulled membrane tethers from human embryonic kidney cells using single and multi-speed protocols, and obtained time-resolved tether forces. We quantified various mechanical characteristics including the tether equilibrium force, bending modulus, effective membrane viscosity, and plasma membrane-cytoskeleton adhesion energy, and correlated them to the membrane cholesterol level. Decreases in cholesterol concentration were associated with increases in the tether equilibrium force, tether stiffness, and adhesion energy. Tether diameter and effective viscosity increased with increasing cholesterol levels. Disruption of cytoskeletal F-actin significantly changed the tether diameters in both non-cholesterol and cholesterol-manipulated cells, while the effective membrane viscosity was unaffected by F-actin disruption. The findings are relevant to inner ear function where cochlear amplification is altered by changes in membrane cholesterol content.
Collapse
Affiliation(s)
- Nima Khatibzadeh
- Department of Mechanical Engineering, University of California, Riverside, CA 92521, USA
| | - Sharad Gupta
- Department of Bioengineering, University of California, Riverside, CA 92521,USA
| | - Brenda Farrell
- Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery, Baylor College of Medicine, Houston, Texas, TX 77030, USA
| | - William E. Brownell
- Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery, Baylor College of Medicine, Houston, Texas, TX 77030, USA
| | - Bahman Anvari
- Department of Bioengineering, University of California, Riverside, CA 92521,USA
- Tel: 951-827-5726; Fax: 951-827-6416;
| |
Collapse
|
84
|
Thakur P, Fomina AF. Density of functional Ca2+ release-activated Ca2+ (CRAC) channels declines after T-cell activation. Channels (Austin) 2011; 5:510-7. [PMID: 22172731 DOI: 10.4161/chan.5.6.18222] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
CRAC channel-mediated Ca(2+) entry plays a crucial role in T lymphocyte activation. Activated T cells display enhanced Ca(2+) signaling compared with resting T cells; this is partially attributed to activation-induced upregulation of CRAC channel expression. Orai and Stim family genes encode CRAC channel structural elements and regulatory proteins, respectively, but studies of their expression in T cells have led to controversial results. We re-examined Orai and Stim gene expression in resting, activated, and Jurkat T cells. Levels of Orai1 transcripts, encoding the human T cell CRAC channel subunit, were not significantly different between resting T and activated T cells. The total amount of all Orai transcripts was 2-fold higher in activated T cells than in resting T cells. Orai1 and total Orai transcript levels were significantly higher in Jurkat T cells than those in resting T cells. Stim expression did not vary significantly among cell types. Maximal whole-cell CRAC current amplitudes were 1.4-fold and 2.3-fold higher in activated and Jurkat T cells, respectively, than in resting T cells. Due to the small size of resting T cells, the surface CRAC channel density was 2.5-fold and 1.6-fold higher in resting T cells than in activated and Jurkat T cells, respectively. Predicted the rates of cytosolic Ca(2+) elevation calculated using the average values of CRAC channel currents and cell volumes showed that < 2-fold increase in the functional CRAC channel expression level cannot account for the enhanced rate of store-operated Ca(2+) entry in activated T cells compared with resting T cells.
Collapse
|
85
|
Wang B, Weldon AL, Kumnorkaew P, Xu B, Gilchrist JF, Cheng X. Effect of surface nanotopography on immunoaffinity cell capture in microfluidic devices. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:11229-37. [PMID: 21800852 DOI: 10.1021/la2015868] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Immunoaffinity microfluidic devices have recently become a popular choice to isolate specific cells for many applications. To increase cell capture efficiency, several groups have employed capture beds with nanotopography. However, no systematic study has been performed to quantitatively correlate surface nanopatterns with immunoaffinity cell immobilization. In this work, we controlled substrate topography by depositing close-packed arrays of silica nanobeads with uniform diameters ranging from 100 to 1150 nm onto flat glass. These surfaces were functionalized with a specific antibody and assembled as the base in microfluidic channels, which were then used to capture CD4+ T cells under continuous flow. It is observed that capture efficiency generally increases with nanoparticle size under low flow rate. At higher flow rates, cell capture efficiency becomes increasingly complex; it initially increases with the bead size then gradually decreases. Surprisingly, capture yield plummets atop depositions of some particle diameters. These dips likely stem from dynamic interactions between nanostructures on the substrate and cell membrane as indicated by roughness-insensitive cell capture after glutaraldehyde fixing. This systematic study of surface nanotopography and cell capture efficiency will help optimize the physical properties of microfluidic capture beds for cell isolation from biological fluids.
Collapse
Affiliation(s)
- Bu Wang
- Department of Materials Science and Engineering, Lehigh University, 5 E. Packer Avenue, Bethlehem, Pennsylvania 18015, USA
| | | | | | | | | | | |
Collapse
|
86
|
Yamane J, Ohnishi H, Sasaki H, Narimatsu H, Ohgushi H, Tachibana K. Formation of microvilli and phosphorylation of ERM family proteins by CD43, a potent inhibitor for cell adhesion: cell detachment is a potential cue for ERM phosphorylation and organization of cell morphology. Cell Adh Migr 2011; 5:119-32. [PMID: 21045567 DOI: 10.4161/cam.5.2.13908] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
CD43/sialophorin/leukosialin, a common leukocyte antigen, is known as an inhibitor for cell adhesion. The ectodomain of CD43 is considered as a molecular barrier for cell adhesion, while the cytoplasmic domain has a binding site for Ezrin/Radixin/Moesin (ERM). We found expression of CD43 induced cell rounding, inhibition of cell re-attachment, augmentation of microvilli, and phosphorylation of ERM in HEK293T cells. Mutant studies revealed the ectodomain of CD43, but not the intracellular domain, essential and sufficient for all these phenomena. We also found that forced cell detachment by itself induced phosphorylation of ERM in HEK293T cells. Taken together, these findings indicate that inhibition of cell adhesion by the ectodomain of CD43 induces phosphorylation of ERM, microvilli formation, and eventual cell rounding. Furthermore, our study suggests a novel possibility that cell detachment itself induces activation of ERM and modification of cell shape.
Collapse
Affiliation(s)
- Junko Yamane
- Health Research Institute, Tissue Engineering Research Group, National Institute of Advanced Industrial Science and Technology, Nakouji, Amagasaki, Hyogo, Japan
| | | | | | | | | | | |
Collapse
|
87
|
Atomic force microscopy of microvillous cell surface dynamics at fixed and living alveolar type II cells. Anal Bioanal Chem 2010; 399:2369-78. [DOI: 10.1007/s00216-010-4407-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2010] [Revised: 10/11/2010] [Accepted: 11/02/2010] [Indexed: 10/18/2022]
|
88
|
Harris ES, Gauvin TJ, Heimsath EG, Higgs HN. Assembly of filopodia by the formin FRL2 (FMNL3). Cytoskeleton (Hoboken) 2010; 67:755-72. [PMID: 20862687 DOI: 10.1002/cm.20485] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 09/04/2010] [Accepted: 09/07/2010] [Indexed: 12/31/2022]
Abstract
Actin-dependent finger-like protrusions such as filopodia and microvilli are widespread in eukaryotes, but their assembly mechanisms are poorly understood. Filopodia assembly requires at least three biochemical activities on actin: actin filament nucleation, prolonged actin filament elongation, and actin filament bundling. These activities are shared by several mammalian formin proteins, including mDia2, FRL1 (also called FMNL1), and FRL2 (FMNL3). In this paper, we compare the abilities of constructs from these three formins to induce filopodia. FH1-FH2 constructs of both FRL2 and mDia2 stimulate potent filopodia assembly in multiple cell types, and enrich strongly at filopodia tips. In contrast, FRL1 FH1-FH2 lacks this activity, despite possessing similar biochemical activities and being highly homologous to FRL2. Chimeric FH1-FH2 experiments between FRL1 and FRL2 show that, while both an FH1 and an FH2 are needed, either FH1 domain supports filopodia assembly but only FRL2's FH2 domain allows this activity. A mutation that compromises FRL2's barbed end binding ability abolishes filopodia assembly. FRL2's ability to stimulate filopodia assembly is not altered by additional domains (GBD, DID, DAD), but is significantly reduced in the full-length construct, suggesting that FRL2 is subject to inhibitory regulation. The data suggest that the FH2 domain of FRL2 possesses properties not shared by FRL1 that allow it to generate filopodia.
Collapse
|
89
|
Ruban GI, Berdnik VV, Marinitch DV, Goncharova NV, Loiko VA. Light scattering and morphology of the lymphocyte as applied to flow cytometry for distinguishing healthy and infected individuals. JOURNAL OF BIOMEDICAL OPTICS 2010; 15:057008. [PMID: 21054124 DOI: 10.1117/1.3503404] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A simple optical model of single lymphocytes with smooth and nonsmooth surfaces has been developed for healthy and infected individuals. The model can be used for rapid (in the real-time scale) solution of the inverse light-scattering problem on the basis of optical data measured by label-free flow cytometry. Light scattering patterns have been calculated for the model developed. It has been shown that the smooth and nonsmooth cells can be resolved using the intensities of the sideward- and backward-scattered light. We have found by calculations and validated by the flow cytometer experiments that intensity distributions for the cells of lymphocyte populations can be used as a preliminary signatures of some virus infections. Potential biomedical applications of the findings for label-free flow cytometry detection of individuals infected with viruses of hepatitis B or C and some others viruses are presented.
Collapse
Affiliation(s)
- Gennady I Ruban
- National Academy of Sciences of Belarus, Stepanov Institute of Physics, Nezavisimosti Avenue 68, 220072, Minsk, Belarus.
| | | | | | | | | |
Collapse
|
90
|
A congenital activating mutant of WASp causes altered plasma membrane topography and adhesion under flow in lymphocytes. Blood 2010; 115:5355-65. [PMID: 20354175 DOI: 10.1182/blood-2009-08-236174] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Leukocytes rely on dynamic actin-dependent changes in cell shape to pass through blood vessels, which is fundamental to immune surveillance. Wiskott-Aldrich Syndrome protein (WASp) is a hematopoietic cell-restricted cytoskeletal regulator important for modulating cell shape through Arp2/3-mediated actin polymerization. A recently identified WASp(I294T) mutation was shown to render WASp constitutively active in vivo, causing increased filamentous (F)-actin polymerization, high podosome turnover in macrophages, and myelodysplasia. The aim of this study was to determine the effect of WASp(I294T) expression in lymphocytes. Here, we report that lymphocytes isolated from a patient with WASp(I294T), and in a cellular model of WASp(I294T), displayed abnormal microvillar architecture, associated with an increase in total cellular F-actin. Microvillus function was additionally altered as lymphocytes bearing the WASp(I294T) mutation failed to roll normally on L-selectin ligand under flow. This was not because of defects in L-selectin expression, shedding, cytoskeletal anchorage, or membranal positioning; however, under static conditions of adhesion, WASp(I294T)-expressing lymphocytes exhibited altered dynamic interaction with L-selectin ligand, with a significantly reduced rate of adhesion turnover. Together, our results demonstrate that WASp(I294T) significantly affects lymphocyte membrane topography and L-selectin-dependent adhesion, which may be linked to defective hematopoiesis and leukocyte function in affected patients.
Collapse
|
91
|
Abstract
The Wiskott-Aldrich syndrome protein (WASP) is an important regulator of the actin cytoskeleton that is required for many haematopoietic and immune cell functions, including effective migration, phagocytosis and immune synapse formation. Loss of WASP activity leads to Wiskott-Aldrich syndrome, an X-linked disease that is associated with defects in a broad range of cellular processes, resulting in complex immunodeficiency, autoimmunity and microthrombocytopenia. Intriguingly, gain of function mutations cause a separate disease that is mainly characterized by neutropenia. Here, we describe recent insights into the cellular mechanisms of these two related, but distinct, human diseases and discuss their wider implications for haematopoiesis, immune function and autoimmunity.
Collapse
|
92
|
Strokotov DI, Yurkin MA, Gilev KV, van Bockstaele DR, Hoekstra AG, Rubtsov NB, Maltsev VP. Is there a difference between T- and B-lymphocyte morphology? JOURNAL OF BIOMEDICAL OPTICS 2009; 14:064036. [PMID: 20059274 DOI: 10.1117/1.3275471] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We characterize T- and B-lymphocytes from several donors, determining cell diameter, ratio of nucleus to cell diameter, and refractive index of the nucleus and cytoplasm for each individual cell. We measure light-scattering profiles with a scanning flow cytometer and invert the signals using a coated sphere as an optical model of the cell and by relying on a global optimization technique. The main difference in morphology of T- and B-lymphocytes is found to be the larger mean diameters of the latter. However, the difference is smaller than the natural biological variability of a single cell. We propose nuclear inhomogeneity as a possible reason for the deviation of measured light-scattering profiles from real lymphocytes from those obtained from the coated sphere model.
Collapse
Affiliation(s)
- Dmitry I Strokotov
- Institute of Chemical Kinetics and Combustion, Siberian Branch RAS, Institutskaya 3, Novosibirsk, 630090, Russia
| | | | | | | | | | | | | |
Collapse
|
93
|
Hocdé SA, Hyrien O, Waugh RE. Cell adhesion molecule distribution relative to neutrophil surface topography assessed by TIRFM. Biophys J 2009; 97:379-87. [PMID: 19580776 DOI: 10.1016/j.bpj.2009.04.035] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2008] [Revised: 03/17/2009] [Accepted: 04/23/2009] [Indexed: 11/28/2022] Open
Abstract
The positioning of adhesion molecules relative to the microtopography of the cell surface has a significant influence on the molecule's availability to form adhesive contacts. Measurements of the ratio of fluorescence intensity per unit area in epi-fluorescence images versus total internal reflection fluorescence images provides a means to assess the relative accessibility for bond formation of different fluorescently labeled molecules in cells pressed against a flat substrate. Measurements of the four principal adhesion molecules on human neutrophils reveal that L-selectin has the highest ratio of total internal reflection fluorescence/epi intensity, and that P-selectin glycoprotein ligand-1 (PSGL-1) and the integrins alphaLbeta2 (LFA-1) and alphaMbeta2 (Mac-1) have ratios similar to each other but lower than for L-selectin. All of the ratios increased with increasing impingement, indicating an alteration of surface topography with increasing surface compression. These results are consistent with model predictions for molecules concentrated near the tips of microvilli in the case of L-selectin, and sequestered away from the microvillus tips in the case of LFA-1, Mac-1, and PSGL-1. The results confirm differences among adhesion molecules in their surface distribution and reveal how the availability of specific adhesion molecules is altered by mechanical compression of the surface in live cells.
Collapse
Affiliation(s)
- Sandrine A Hocdé
- Department of Biomedical Engineering, University of Rochester, Rochester, New York, USA
| | | | | |
Collapse
|
94
|
The Arp2/3 complex and WASp are required for apical trafficking of Delta into microvilli during cell fate specification of sensory organ precursors. Nat Cell Biol 2009; 11:815-24. [PMID: 19543274 DOI: 10.1038/ncb1888] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Accepted: 03/17/2009] [Indexed: 12/21/2022]
Abstract
Cell fate decisions mediated by the Notch signalling pathway require direct cell-cell contact between adjacent cells. In Drosophila melanogaster, an external sensory organ (ESO) develops from a single sensory organ precursor (SOP) and its fate specification is governed by differential Notch activation. Here we show that mutations in actin-related protein-3 (Arp3) compromise Notch signalling, leading to a fate transformation of the ESO. Our data reveal that during ESO fate specification, most endocytosed vesicles containing the ligand Delta traffic to a prominent apical actin-rich structure (ARS) formed in the SOP daughter cells. Using immunohistochemistry and transmission electron microscopy (TEM) analyses, we show that the ARS contains numerous microvilli on the apical surface of SOP progeny. In Arp2/3 and WASp mutants, the surface area of the ARS is substantially reduced and there are significantly fewer microvilli. More importantly, trafficking of Delta-positive vesicles from the basal area to the apical portion of the ARS is severely compromised. Our data indicate that WASp-dependent Arp2/3 actin polymerization is crucial for apical presentation of Delta, providing a mechanistic link between actin polymerization and Notch signalling.
Collapse
|
95
|
|
96
|
Khismatullin DB. Chapter 3 The Cytoskeleton and Deformability of White Blood Cells. CURRENT TOPICS IN MEMBRANES 2009. [DOI: 10.1016/s1063-5823(09)64003-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
97
|
Chapter 2 Biomechanics of Leukocyte and Endothelial Cell Surface. CURRENT TOPICS IN MEMBRANES 2009. [DOI: 10.1016/s1063-5823(09)64002-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
|
98
|
Nicholson-Dykstra SM, Higgs HN. Arp2 depletion inhibits sheet-like protrusions but not linear protrusions of fibroblasts and lymphocytes. ACTA ACUST UNITED AC 2008; 65:904-22. [PMID: 18720401 DOI: 10.1002/cm.20312] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The Arp2/3 complex-mediated assembly and protrusion of a branched actin network at the leading edge occurs during cell migration, although some studies suggest it is not essential. In order to test the role of Arp2/3 complex in leading edge protrusion, Swiss 3T3 fibroblasts and Jurkat T cells were depleted of Arp2 and evaluated for defects in cell morphology and spreading efficiency. Arp2-depleted fibroblasts exhibit severe defects in formation of sheet-like protrusions at early time points of cell spreading, with sheet-like protrusions limited to regions along the length of linear protrusions. However, Arp2-depleted cells are able to spread fully after extended times. Similarly, Arp2-depleted Jurkat T lymphocytes exhibit defects in spreading on anti-CD3. Interphase Jurkats in suspension are covered with large ruffle structures, whereas mitotic Jurkats are covered by finger-like linear protrusions. Arp2-depleted Jurkats exhibit defects in ruffle assembly but not in assembly of mitotic linear protrusions. Similarly, Arp2-depletion has no effect on the highly dynamic linear protrusion of another suspended lymphocyte line. We conclude that Arp2/3 complex plays a significant role in assembly of sheet-like protrusions, especially during early stages of cell spreading, but is not required for assembly of a variety of linear actin-based protrusions.
Collapse
|
99
|
Xu G, Shao JY. Human neutrophil surface protrusion under a point load: location independence and viscoelasticity. Am J Physiol Cell Physiol 2008; 295:C1434-44. [PMID: 18815230 DOI: 10.1152/ajpcell.00136.2008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Mechanical properties of neutrophils have been recognized as key contributors to stabilizing neutrophil rolling on the endothelium during the inflammatory response. In particular, accumulating evidence suggests that surface protrusion and tether extraction from neutrophils facilitate stable rolling by relieving the disruptive forces on adhesive bonds. Using a customized optical trap setup, we applied piconewton-level pulling forces on targeted receptors that were located either on the microvillus tip (CD162) or intermicrovillus surface of neutrophils (CD18 and CD44). Under a constant force-loading rate, there always occurred an initial tent-like surface protrusion that was terminated either by rupture of the adhesion or by a "yield" or "crossover" to tether extraction. The corresponding protrusional stiffness of neutrophils was found to be between 0.06 and 0.11 pN/nm, depending on the force-loading rate and the cytoskeletal integrity, but not on the force location, the medium osmolality, nor the temperature increase from 22 degrees C to 37 degrees C. More importantly, we found that neutrophil surface protrusion was accompanied by force relaxation and hysteresis. In addition, the crossover force did not change much in the range of force-loading rates studied, and the protrusional stiffness of lymphocytes was similar to that of neutrophils. These results show that neutrophil surface protrusion is essentially viscoelastic, with a protrusional stiffness that stems primarily from the actin cortex, and the crossover force is independent of the receptor-cytoskeleton interaction.
Collapse
Affiliation(s)
- Gang Xu
- Dept. of Biomedical Engineering, Washington Univ. in St. Louis, Campus Box 1097, Rm 290E Whitaker Hall, One Brookings Dr., St. Louis, MO 63130-4899, USA
| | | |
Collapse
|
100
|
Membrane mobility of beta2 integrins and rolling associated adhesion molecules in resting neutrophils. Biophys J 2008; 95:4934-47. [PMID: 18689449 DOI: 10.1529/biophysj.108.132886] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The mobilities of transmembrane adhesion proteins are key underlying physical factors that contribute to neutrophil adhesion and arrest during inflammation. Here we present a novel (to our knowledge) fluorescence recovery after photobleaching system and a complementary analytical model to measure the mobility of the four key receptors involved in the adhesion cascade: L-selectin, PSGL-1, Mac-1, and LFA-1 for resting, spherical, and human neutrophils. In general, we find that beta(2) integrins (Mac-1, LFA-1) have mobilities 3-7 times faster than rolling associated molecules (L-selectin; PSGL-1), but that the mobilities within each of these groups are indistinguishable. Increasing temperature (room temperature versus 37 degrees C) results in increased mobility, in all cases, and the use of a bivalent antibody label (mAb versus Fab) decreases mobility, except in the case of rolling associated molecules at room temperature. Disrupting the actin cytoskeleton increased mobility except that the highest mobilities measured for integrins (D = 1.2 x 10(-9) cm(2)/s; 37 degrees C, Fab) are not affected by actin poisons and approach the expected value for free diffusion. Although evidence of cytoskeletal hindrance of integrin mobility has been found in other systems, our data suggest such hindrance does not limit bulk integrin diffusion in resting neutrophils over distances and times important for adhesive plaque formation.
Collapse
|