1
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Schrope JH, Horn A, Farooqui M, Lazorchak K, Li J, Tinnen C, Stevens JJ, Bennin D, Robertson T, Juang T, Li C, Huttenlocher A, Beebe DJ. Liquid-liquid interfaces enable tunable cell confinement to recapitulate surrounding tissue deformations during neutrophil interstitial migration in vivo. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.14.544898. [PMID: 38106211 PMCID: PMC10723256 DOI: 10.1101/2023.06.14.544898] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2023]
Abstract
Cell migration is regulated by an interplay between both chemical and mechanical cues. Immune cells navigate through interstitial spaces and generate forces to deform surrounding cells, which in turn exert opposing pressures that regulate cell morphology and motility mechanisms. Current in vitro systems to study confined cell migration largely utilize rigid materials orders of magnitude stiffer than surrounding cells, limiting insights into how these local physical interactions regulate interstitial cell motility. Here, we first characterize mechanical interactions between neutrophils and surrounding cells in larval zebrafish and subsequently engineer in vitro migration channels bound by a deformable liquid-liquid interface that responds to cell generated pressures yielding a gradient of confinement across the length of a single cell. Tuning confining pressure gradients replicates mechanical interactions with surrounding cells during interstitial migration in vivo . We find that neutrophils favor a bleb-based mechanism of force generation to deform a barrier applying cell-scale confining forces. This work introduces a biomimetic material interface that enables new avenues of exploring the influence of mechanical forces on cell migration.
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2
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Son M, Wang AG, Kenna E, Tay S. High-throughput co-culture system for analysis of spatiotemporal cell-cell signaling. Biosens Bioelectron 2023; 225:115089. [PMID: 36736159 PMCID: PMC9991101 DOI: 10.1016/j.bios.2023.115089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/31/2023]
Abstract
Study of spatial and temporal aspects of signaling between individual cells is essential in understanding development, the immune response, and host-pathogen interactions. We present an automated high-throughput microfluidic platform that chemically stimulates immune cells to initiate cytokine secretion, and controls the formation of signal gradients that activate neighboring cell populations. Furthermore, our system enables controlling the cell type and density based on distance, and retrieval of cells from different regions for gene expression analysis. Our device performs these tasks in 192 independent chambers to simultaneously test different co-culture conditions. We demonstrate these capabilities by creating various cellular communication scenarios between macrophages and fibroblasts in vitro. We find that spatial distribution of macrophages and heterogeneity in cytokine secretion determine spatiotemporal gene expression responses. Furthermore, we describe how gene expression dynamics depend on a cell's distance from the signaling source. Our device addresses key challenges in the study of cell-to-cell signaling, and provides high-throughput and automated analysis over a wide range of co-culture conditions.
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Affiliation(s)
- Minjun Son
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA; Institute for Genomics and Systems Biology, University of Chicago, Chicago, IL, 60637, USA.
| | - Andrew G Wang
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA; Medical Scientist Training Program, University of Chicago, Chicago, IL, 60637, USA
| | - Emma Kenna
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA
| | - Savaş Tay
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA; Institute for Genomics and Systems Biology, University of Chicago, Chicago, IL, 60637, USA.
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3
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Ellett F, Irimia D. Passive redirection filters minimize red blood cell contamination during neutrophil chemotaxis assays using whole blood. LAB ON A CHIP 2023; 23:1879-1885. [PMID: 36857665 DOI: 10.1039/d2lc00903j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Neutrophils are the most numerous white blood cells and are the first to arrive at sites of inflammation and infection. Thus, neutrophil behavior provides a comprehensive biomarker for antimicrobial defenses. Several microfluidic tools have been developed to test neutrophil chemotaxis, phagocytosis, extrusion of extracellular traps, etc. Traditional tools rely on purified neutrophil samples, which require lengthy and expensive isolation procedures from large volumes of blood. In the absence of such isolation, visualizing neutrophils in blood is complicated by the overwhelming number of red blood cells (RBCs), which outnumber neutrophils by 1000 : 1. Recently, several microfluidic technologies have been designed to analyze neutrophils directly in blood, by separating neutrophils on selectin coated surfaces before the migration assay or blocking the advance of RBCs with the moving neutrophils. However, RBC contamination remains an issue, albeit with a reduced ratio, down to 1 : 1. Here, we present an RBC-debulking strategy for neutrophil assays based on microscale passive redirection filters (PRFs) that reduce RBC contamination down to as few as a 1 : 17 RBC to neutrophil ratio. We compare the performance of different PRF designs and measure changes in neutrophil chemotaxis velocity and directionality following immune stimulation of whole blood.
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Affiliation(s)
- Felix Ellett
- BioMEMS Resource Center, Center for Engineering in Medicine and Surgery, Massachusetts General Hospital, Shriners Hospital for Children, Harvard Medical School, Boston, Massachusetts, USA.
| | - Daniel Irimia
- BioMEMS Resource Center, Center for Engineering in Medicine and Surgery, Massachusetts General Hospital, Shriners Hospital for Children, Harvard Medical School, Boston, Massachusetts, USA.
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4
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Hadjitheodorou A, Bell GRR, Ellett F, Irimia D, Tibshirani R, Collins SR, Theriot JA. Leading edge competition promotes context-dependent responses to receptor inputs to resolve directional dilemmas in neutrophil migration. Cell Syst 2023; 14:196-209.e6. [PMID: 36827986 PMCID: PMC10150694 DOI: 10.1016/j.cels.2023.02.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 09/02/2022] [Accepted: 01/31/2023] [Indexed: 02/25/2023]
Abstract
Maintaining persistent migration in complex environments is critical for neutrophils to reach infection sites. Neutrophils avoid getting trapped, even when obstacles split their front into multiple leading edges. How they re-establish polarity to move productively while incorporating receptor inputs under such conditions remains unclear. Here, we challenge chemotaxing HL60 neutrophil-like cells with symmetric bifurcating microfluidic channels to probe cell-intrinsic processes during the resolution of competing fronts. Using supervised statistical learning, we demonstrate that cells commit to one leading edge late in the process, rather than amplifying structural asymmetries or early fluctuations. Using optogenetic tools, we show that receptor inputs only bias the decision similarly late, once mechanical stretching begins to weaken each front. Finally, a retracting edge commits to retraction, with ROCK limiting sensitivity to receptor inputs until the retraction completes. Collectively, our results suggest that cell edges locally adopt highly stable protrusion/retraction programs that are modulated by mechanical feedback.
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Affiliation(s)
- Amalia Hadjitheodorou
- Department of Bioengineering, Stanford University, Stanford, CA, USA; Department of Biology and Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
| | - George R R Bell
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, CA, USA
| | - Felix Ellett
- Department of Surgery, BioMEMS Resource Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Daniel Irimia
- Department of Surgery, BioMEMS Resource Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Robert Tibshirani
- Department of Statistics and Biomedical Data Science, Stanford University, Stanford, CA, USA
| | - Sean R Collins
- Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, CA, USA.
| | - Julie A Theriot
- Department of Biology and Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA.
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5
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Kalashnikov N, Moraes C. Engineering physical microenvironments to study innate immune cell biophysics. APL Bioeng 2022; 6:031504. [PMID: 36156981 PMCID: PMC9492295 DOI: 10.1063/5.0098578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 08/22/2022] [Indexed: 12/04/2022] Open
Abstract
Innate immunity forms the core of the human body's defense system against infection, injury, and foreign objects. It aims to maintain homeostasis by promoting inflammation and then initiating tissue repair, but it can also lead to disease when dysregulated. Although innate immune cells respond to their physical microenvironment and carry out intrinsically mechanical actions such as migration and phagocytosis, we still do not have a complete biophysical description of innate immunity. Here, we review how engineering tools can be used to study innate immune cell biophysics. We first provide an overview of innate immunity from a biophysical perspective, review the biophysical factors that affect the innate immune system, and then explore innate immune cell biophysics in the context of migration, phagocytosis, and phenotype polarization. Throughout the review, we highlight how physical microenvironments can be designed to probe the innate immune system, discuss how biophysical insight gained from these studies can be used to generate a more comprehensive description of innate immunity, and briefly comment on how this insight could be used to develop mechanical immune biomarkers and immunomodulatory therapies.
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Affiliation(s)
- Nikita Kalashnikov
- Department of Chemical Engineering, McGill University, Montreal, Quebec H3A 0G4, Canada
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6
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Kroll J, Ruiz-Fernandez MJA, Braun MB, Merrin J, Renkawitz J. Quantifying the Probing and Selection of Microenvironmental Pores by Motile Immune Cells. Curr Protoc 2022; 2:e407. [PMID: 35384410 DOI: 10.1002/cpz1.407] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Immune cells are constantly on the move through multicellular organisms to explore and respond to pathogens and other harmful insults. While moving, immune cells efficiently traverse microenvironments composed of tissue cells and extracellular fibers, which together form complex environments of various porosity, stiffness, topography, and chemical composition. In this protocol we describe experimental procedures to investigate immune cell migration through microenvironments of heterogeneous porosity. In particular, we describe micro-channels, micro-pillars, and collagen networks as cell migration paths with alternative pore size choices. Employing micro-channels or micro-pillars that divide at junctions into alternative paths with initially differentially sized pores allows us to precisely (1) measure the cellular translocation time through these porous path junctions, (2) quantify the cellular preference for individual pore sizes, and (3) image cellular components like the nucleus and the cytoskeleton. This reductionistic experimental setup thus can elucidate how immune cells perform decisions in complex microenvironments of various porosity like the interstitium. The setup further allows investigation of the underlying forces of cellular squeezing and the consequences of cellular deformation on the integrity of the cell and its organelles. As a complementary approach that does not require any micro-engineering expertise, we describe the usage of three-dimensional collagen networks with different pore sizes. Whereas we here focus on dendritic cells as a model for motile immune cells, the described protocols are versatile as they are also applicable for other immune cell types like neutrophils and non-immune cell types such as mesenchymal and cancer cells. In summary, we here describe protocols to identify the mechanisms and principles of cellular probing, decision making, and squeezing during cellular movement through microenvironments of heterogeneous porosity. © 2022 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Immune cell migration in micro-channels and micro-pillars with defined pore sizes Support Protocol 1: Epoxy replica of generated and/or published micro-structures Support Protocol 2: Dendritic cell differentiation Basic Protocol 2: Immune cell migration in 3D collagen networks of variable pore sizes.
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Affiliation(s)
- Janina Kroll
- Biomedical Center (BMC), Walter Brendel Center of Experimental Medicine, Institute of Cardiovascular Physiology and Pathophysiology, Klinikum der Universität, Ludwig Maximilians Universität (LMU) München, München, Germany
| | - Mauricio J A Ruiz-Fernandez
- Biomedical Center (BMC), Walter Brendel Center of Experimental Medicine, Institute of Cardiovascular Physiology and Pathophysiology, Klinikum der Universität, Ludwig Maximilians Universität (LMU) München, München, Germany
| | - Malte B Braun
- Biomedical Center (BMC), Walter Brendel Center of Experimental Medicine, Institute of Cardiovascular Physiology and Pathophysiology, Klinikum der Universität, Ludwig Maximilians Universität (LMU) München, München, Germany
| | - Jack Merrin
- Institute of Science and Technology Austria (IST Austria), Klosterneuburg, Austria
| | - Jörg Renkawitz
- Biomedical Center (BMC), Walter Brendel Center of Experimental Medicine, Institute of Cardiovascular Physiology and Pathophysiology, Klinikum der Universität, Ludwig Maximilians Universität (LMU) München, München, Germany
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7
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Ellett F, Marand AL, Irimia D. Multifactorial assessment of neutrophil chemotaxis efficiency from a drop of blood. J Leukoc Biol 2022; 111:1175-1184. [PMID: 35100458 DOI: 10.1002/jlb.3ma0122-378rr] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 01/13/2022] [Accepted: 01/17/2022] [Indexed: 11/07/2022] Open
Abstract
Following injury and infection, neutrophils are guided to the affected site by chemoattractants released from injured tissues and invading microbes. During this process (chemotaxis), neutrophils must integrate multiple chemical signals, while also responding to physical constraints and prioritizing their directional decisions to generate an efficient immune response. In some clinical conditions, human neutrophils appear to lose the ability to chemotax efficiently, which may contribute both directly and indirectly to disease pathology. Here, a range of microfluidic designs is utilized to test the sensitivity of chemotaxing neutrophils to various perturbations, including binary decision-making in the context of channels with different chemoattractant gradients, hydraulic resistance, and angle of approach. Neutrophil migration in long narrow channels and planar environments is measured. Conditions in which neutrophils are significantly more likely to choose paths with the steepest chemoattractant gradient and the most direct approach angle, and find that migration efficiency across planar chambers is inversely correlated with chamber diameter. By sequential measurement of neutrophil binary decision-making to different chemoattractant gradients, or chemotactic index in sequential planar environments, data supporting a model of biased random walk for neutrophil chemotaxis are presented.
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Affiliation(s)
- Felix Ellett
- BioMEMS Resource Center, Division of Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General Hospital, Shriners Burns Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Anika L Marand
- BioMEMS Resource Center, Division of Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General Hospital, Shriners Burns Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Daniel Irimia
- BioMEMS Resource Center, Division of Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General Hospital, Shriners Burns Hospital, Harvard Medical School, Boston, Massachusetts, USA
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8
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Vesperini D, Montalvo G, Qu B, Lautenschläger F. Characterization of immune cell migration using microfabrication. Biophys Rev 2021; 13:185-202. [PMID: 34290841 PMCID: PMC8285443 DOI: 10.1007/s12551-021-00787-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 01/24/2021] [Indexed: 12/14/2022] Open
Abstract
The immune system provides our defense against pathogens and aberrant cells, including tumorigenic and infected cells. Motility is one of the fundamental characteristics that enable immune cells to find invading pathogens, control tissue damage, and eliminate primary developing tumors, even in the absence of external treatments. These processes are termed "immune surveillance." Migration disorders of immune cells are related to autoimmune diseases, chronic inflammation, and tumor evasion. It is therefore essential to characterize immune cell motility in different physiologically and pathologically relevant scenarios to understand the regulatory mechanisms of functionality of immune responses. This review is focused on immune cell migration, to define the underlying mechanisms and the corresponding investigative approaches. We highlight the challenges that immune cells encounter in vivo, and the microfabrication methods to mimic particular aspects of their microenvironment. We discuss the advantages and disadvantages of the proposed tools, and provide information on how to access them. Furthermore, we summarize the directional cues that regulate individual immune cell migration, and discuss the behavior of immune cells in a complex environment composed of multiple directional cues.
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Affiliation(s)
- Doriane Vesperini
- Department of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany
- Center for Biophysics, Saarland University, 66123 Saarbrücken, Germany
| | - Galia Montalvo
- Department of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany
- Center for Biophysics, Saarland University, 66123 Saarbrücken, Germany
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, 66421 Homburg, Germany
| | - Bin Qu
- Biophysics, Center for Integrative Physiology and Molecular Medicine (CIPMM), School of Medicine, Saarland University, 66421 Homburg, Germany
- Leibniz Institute for New Materials, 66123 Saarbrücken, Germany
| | - Franziska Lautenschläger
- Department of Experimental Physics, Saarland University, 66123 Saarbrücken, Germany
- Center for Biophysics, Saarland University, 66123 Saarbrücken, Germany
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9
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Principles of Leukocyte Migration Strategies. Trends Cell Biol 2020; 30:818-832. [DOI: 10.1016/j.tcb.2020.06.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 12/14/2022]
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10
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Chemotaxing neutrophils enter alternate branches at capillary bifurcations. Nat Commun 2020; 11:2385. [PMID: 32404937 PMCID: PMC7220926 DOI: 10.1038/s41467-020-15476-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 03/06/2020] [Indexed: 12/14/2022] Open
Abstract
Upon tissue injury or microbial invasion, a large number of neutrophils converge from blood to the sites of injury or infection in a short time. The migration through a limited number of paths through tissues and capillary networks seems efficient and 'traffic jams' are generally avoided. However, the mechanisms that guide efficient trafficking of large numbers of neutrophils through capillary networks are not well understood. Here we show that pairs of neutrophils arriving closely one after another at capillary bifurcations migrate to alternating branches in vivo and in vitro. Perturbation of chemoattractant gradients and the increased hydraulic resistance induced by the first neutrophil in one branch biases the migration of the following neutrophil towards the other branch. These mechanisms guide neutrophils to efficiently navigate through capillary networks and outline the effect of inter-neutrophil interactions during migration on overall lymphocyte trafficking patterns in confined environments.
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11
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Pham QL, Tong A, Rodrigues LN, Zhao Y, Surblyte M, Ramos D, Brito J, Rahematpura A, Voronov RS. Ranking migration cue contributions to guiding individual fibroblasts faced with a directional decision in simple microfluidic bifurcations. Integr Biol (Camb) 2020; 11:208-220. [PMID: 31251334 DOI: 10.1093/intbio/zyz018] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 04/04/2019] [Accepted: 05/21/2019] [Indexed: 01/02/2023]
Abstract
Directed cell migration in complex micro-environments, such as in vivo pores, is important for predicting locations of artificial tissue growth and optimizing scaffold architectures. Yet, the directional decisions of cells facing multiple physiochemical cues have not been characterized. Hence, we aim to provide a ranking of the relative importance of the following cues to the decision-making of individual fibroblast cells: chemoattractant concentration gradient, channel width, mitosis, and contact-guidance. In this study, bifurcated micro-channels with branches of different widths were created. Fibroblasts were then allowed to travel across these geometries by following a gradient of platelet-derived growth factor-BB (PDGF-BB) established inside the channels. Subsequently, a combination of statistical analysis and image-based diffusion modeling was used to report how the presence of multiple complex migration cues, including cell-cell influences, affect the fibroblast decision-making. It was found that the cells prefer wider channels over a higher chemoattractant gradient when choosing between asymmetric bifurcated branches. Only when the branches were symmetric in width did the gradient become predominant in directing which path the cell will take. Furthermore, when both the gradient and the channels were symmetric, contact guidance became important for guiding the cells in making directional choices. Based on these results we were able to rank these directional cues from most influential to the least as follows: mitosis > channel width asymmetry > chemoattractant gradient difference > and contact-guidance. It is expected that these results will benefit the fields of regenerative medicine, wound healing and developmental biology.
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Affiliation(s)
- Quang Long Pham
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | - Anh Tong
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | - Lydia N Rodrigues
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | - Yang Zhao
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | - Migle Surblyte
- Ying Wu College of Computing Sciences, Department of Computer Science, New Jersey Institute of Technology, Newark, NJ, USA
| | - Diomar Ramos
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | - John Brito
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | - Adwik Rahematpura
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, USA
| | - Roman S Voronov
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ, USA
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12
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Energetic costs regulated by cell mechanics and confinement are predictive of migration path during decision-making. Nat Commun 2019; 10:4185. [PMID: 31519914 PMCID: PMC6744572 DOI: 10.1038/s41467-019-12155-z] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 08/15/2019] [Indexed: 02/07/2023] Open
Abstract
Cell migration during the invasion-metastasis cascade requires cancer cells to navigate a spatially complex microenvironment that presents directional choices to migrating cells. Here, we investigate cellular energetics during migration decision-making in confined spaces. Theoretical and experimental data show that energetic costs for migration through confined spaces are mediated by a balance between cell and matrix compliance as well as the degree of spatial confinement to direct decision-making. Energetic costs, driven by the cellular work needed to generate force for matrix displacement, increase with increasing cell stiffness, matrix stiffness, and degree of spatial confinement, limiting migration. By assessing energetic costs between possible migration paths, we can predict the probability of migration choice. Our findings indicate that motility in confined spaces imposes high energetic demands on migrating cells, and cells migrate in the direction of least confinement to minimize energetic costs. Therefore, therapeutically targeting metabolism may limit cancer cell migration and metastasis.
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13
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Um E, Oh JM, Park J, Song T, Kim TE, Choi Y, Shin C, Kolygina D, Jeon JH, Grzybowski BA, Cho YK. Immature dendritic cells navigate microscopic mazes to find tumor cells. LAB ON A CHIP 2019; 19:1665-1675. [PMID: 30931468 DOI: 10.1039/c9lc00150f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Dendritic cells (DCs) are potent antigen-presenting cells with high sentinel ability to scan their neighborhood and to initiate an adaptive immune response. Whereas chemotactic migration of mature DCs (mDCs) towards lymph nodes is relatively well documented, the migratory behavior of immature DCs (imDCs) in tumor microenvironments is still poorly understood. Here, microfluidic systems of various geometries, including mazes, are used to investigate how the physical and chemical microenvironment influences the migration pattern of imDCs. Under proper degree of confinement, the imDCs are preferentially recruited towards cancer vs. normal cells, accompanied by increased cell speed and persistence. Furthermore, a systematic screen of cytokines, reveals that Gas6 is a major chemokine responsible for the chemotactic preference. These results and the accompanying theoretical model suggest that imDC migration in complex tissue environments is tuned by a proper balance between the strength of the chemical gradients and the degree of spatial confinement.
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Affiliation(s)
- Eujin Um
- Center for Soft and Living Matter, Institute for Basic Science (IBS), Ulsan, 44919, Republic of Korea
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14
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Boribong BP, Lenzi MJ, Li L, Jones CN. Super-Low Dose Lipopolysaccharide Dysregulates Neutrophil Migratory Decision-Making. Front Immunol 2019; 10:359. [PMID: 30915068 PMCID: PMC6422936 DOI: 10.3389/fimmu.2019.00359] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 02/12/2019] [Indexed: 12/30/2022] Open
Abstract
Neutrophils are the first responders to infection and play a pivotal role in many inflammatory diseases, including sepsis. Recent studies have shown that lipopolysaccharide (LPS), a classical pattern recognition molecule, dynamically programs innate immune responses. In this study, we show that pre-treatment with super-low levels of LPS [1 ng/mL] significantly dysregulate neutrophil migratory phenotypes, including spontaneous migration and altering neutrophil decision-making. To quantify neutrophil migratory decision-making with single-cell resolution, we developed a novel microfluidic competitive chemotaxis-chip (μC3) that exposes cells in a central channel to competing chemoattractant gradients. In this reductionist approach, we use two chemoattractants: a pro-resolution (N-Formyl-Met-Leu-Phe, fMLP) and pro-inflammatory (Leukotriene B4, LTB4) chemoattractant to model how a neutrophil makes a decision to move toward an end target chemoattractant (e.g., bacterial infection) vs. an intermediary chemoattractant (e.g., inflammatory signal). We demonstrate that naïve neutrophils migrate toward the primary end target signal in higher percentages than toward the secondary intermediary signal. As expected, we found that training with high dose LPS [100 ng/mL] influences a higher percentage of neutrophils to migrate toward the end target signal, while reducing the percentage of neutrophils that migrate toward the intermediary signal. Surprisingly, super-low dose LPS [1 ng/mL] significantly changes the ratios of migrating cells and an increased percentage of cells migrate toward the intermediary signal. Significantly, there was also an increase in the numbers of spontaneously migrating neutrophils after treatment with super-low dose LPS. These results shed light onto the directional migratory decision-making of neutrophils exposed to inflammatory training signals. Understanding these mechanisms may lead to the development of pro-resolution therapies that correct the neutrophil compass and reduce off-target organ damage.
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Affiliation(s)
- Brittany P Boribong
- Genetics, Bioinformatics, and Computational Biology, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Mark J Lenzi
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Liwu Li
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
| | - Caroline N Jones
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA, United States
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15
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Garcia-Arcos JM, Chabrier R, Deygas M, Nader G, Barbier L, Sáez PJ, Mathur A, Vargas P, Piel M. Reconstitution of cell migration at a glance. J Cell Sci 2019; 132:132/4/jcs225565. [PMID: 30745333 DOI: 10.1242/jcs.225565] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Single cells migrate in a myriad of physiological contexts, such as tissue patrolling by immune cells, and during neurogenesis and tissue remodeling, as well as in metastasis, the spread of cancer cells. To understand the basic principles of single-cell migration, a reductionist approach can be taken. This aims to control and deconstruct the complexity of different cellular microenvironments into simpler elementary constrains that can be recombined together. This approach is the cell microenvironment equivalent of in vitro reconstituted systems that combine elementary molecular players to understand cellular functions. In this Cell Science at a Glance article and accompanying poster, we present selected experimental setups that mimic different events that cells undergo during migration in vivo These include polydimethylsiloxane (PDMS) devices to deform whole cells or organelles, micro patterning, nano-fabricated structures like grooves, and compartmentalized collagen chambers with chemical gradients. We also outline the main contribution of each technique to the understanding of different aspects of single-cell migration.
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Affiliation(s)
- Juan Manuel Garcia-Arcos
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Renaud Chabrier
- Institut Curie, PSL Research University, CNRS UMR3348, F-91405 Orsay, France
| | - Mathieu Deygas
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Guilherme Nader
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Lucie Barbier
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Pablo José Sáez
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Aastha Mathur
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Pablo Vargas
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France.,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
| | - Matthieu Piel
- Institut Curie, PSL Research University, CNRS, UMR 144, F-75005 Paris, France .,Institut Pierre-Gilles de Gennes, PSL Research University, F-75005 Paris, France
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16
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Salvermoser M, Begandt D, Alon R, Walzog B. Nuclear Deformation During Neutrophil Migration at Sites of Inflammation. Front Immunol 2018; 9:2680. [PMID: 30505310 PMCID: PMC6250837 DOI: 10.3389/fimmu.2018.02680] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Accepted: 10/30/2018] [Indexed: 12/22/2022] Open
Abstract
Cell migration is indispensable for various biological processes including angiogenesis, wound healing, and immunity. In general, there are two different migration modes described, the mesenchymal migration mode and the amoeboid migration mode. Neutrophils rapidly migrate toward the sites of injury, infection, and inflammation using the amoeboid migration mode which is characterized by cell polarization and a high migration velocity. During site-directed trafficking of neutrophils from the blood stream into the inflamed tissue, neutrophils must first withstand shear stress while migrating on the 2-dimensional endothelial surface. Subsequently, they have to cross different physical barriers during the extravasation process including the squeezing through the compact endothelial monolayer that comprises the blood vessel, the underlining basement membrane and then the 3-dimensional meshwork of extracellular matrix (ECM) proteins in the tissue. Therefore, neutrophils have to rapidly switch between distinct migration modes such as intraluminal crawling, transmigration, and interstitial migration to pass these different confinements and mechanical barriers. The nucleus is the largest and stiffest organelle in every cell and is therefore the key cellular element involved in cellular migration through variable confinements. This review highlights the importance of nuclear deformation during neutrophil crossing of such confinements, with a focus on transendothelial migration and interstitial migration. We discuss the key molecular components involved in the nuclear shape changes that underlie neutrophil motility and squeezing through cellular and ECM barriers. Understanding the precise molecular mechanisms that orchestrate these distinct neutrophil migration modes introduces an opportunity to develop new therapeutic concepts for controlling pathological neutrophil-driven inflammation.
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Affiliation(s)
- Melanie Salvermoser
- Walter-Brendel-Centre of Experimental Medicine, University Hospital, Planegg-Martinsried, Germany
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, Planegg-Martinsried, Germany
| | - Daniela Begandt
- Walter-Brendel-Centre of Experimental Medicine, University Hospital, Planegg-Martinsried, Germany
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, Planegg-Martinsried, Germany
| | - Ronen Alon
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
| | - Barbara Walzog
- Walter-Brendel-Centre of Experimental Medicine, University Hospital, Planegg-Martinsried, Germany
- Institute of Cardiovascular Physiology and Pathophysiology, Biomedical Center, Planegg-Martinsried, Germany
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17
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In vitro and ex vivo systems at the forefront of infection modeling and drug discovery. Biomaterials 2018; 198:228-249. [PMID: 30384974 PMCID: PMC7172914 DOI: 10.1016/j.biomaterials.2018.10.030] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Revised: 10/05/2018] [Accepted: 10/23/2018] [Indexed: 12/11/2022]
Abstract
Bacterial infections and antibiotic resistant bacteria have become a growing problem over the past decade. As a result, the Centers for Disease Control predict more deaths resulting from microorganisms than all cancers combined by 2050. Currently, many traditional models used to study bacterial infections fail to precisely replicate the in vivo bacterial environment. These models often fail to incorporate fluid flow, bio-mechanical cues, intercellular interactions, host-bacteria interactions, and even the simple inclusion of relevant physiological proteins in culture media. As a result of these inadequate models, there is often a poor correlation between in vitro and in vivo assays, limiting therapeutic potential. Thus, the urgency to establish in vitro and ex vivo systems to investigate the mechanisms underlying bacterial infections and to discover new-age therapeutics against bacterial infections is dire. In this review, we present an update of current in vitro and ex vivo models that are comprehensively changing the landscape of traditional microbiology assays. Further, we provide a comparative analysis of previous research on various established organ-disease models. Lastly, we provide insight on future techniques that may more accurately test new formulations to meet the growing demand of antibiotic resistant bacterial infections.
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18
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Pham QL, Rodrigues LN, Maximov MA, Chandran VD, Bi C, Chege D, Dijamco T, Stein E, Tong NAN, Basuray S, Voronov RS. Cell Sequence and Mitosis Affect Fibroblast Directional Decision-Making During Chemotaxis in Microfluidic Mazes. Cell Mol Bioeng 2018; 11:483-494. [PMID: 31719895 DOI: 10.1007/s12195-018-0551-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Accepted: 08/21/2018] [Indexed: 01/25/2023] Open
Abstract
Introduction Directed fibroblast migration is central to highly proliferative processes in regenerative medicine and developmental biology. However, the mechanisms by which single fibroblasts affect each other's directional decisions, while chemotaxing in microscopic pores, are not well understood. Methods We explored effects of cell sequence and mitosis on fibroblast platelet-derived growth factor-BB (PDGF-BB)-induced migration in microfluidic mazes with two possible through paths: short and long. Additionally, image-based modeling of the chemoattractant's diffusion, consumption and decay, was used to explain the experimental observations. Results It both cases, the cells displayed behavior that is contradictory to expectation based on the global chemoattractant gradient pre-established in the maze. In case of the sequence, the cells tend to alternate when faced with a bifurcation: if a leading cell takes the shorter (steeper gradient) path, the cell following it chooses the longer (weaker gradient) path, and vice versa. Image-based modeling of the process showed that the local PDGF-BB consumption by the individual fibroblasts may be responsible for this phenomenon. Additionally, it was found that when a mother cell divides, its two daughters go in opposite directions (even if it means migrating against the chemoattractant gradient and overcoming on-going cell traffic). Conclusions It is apparent that micro-confined fibroblasts modify each other's directional decisions in a manner that is counter-intuitive to what is expected from classical chemotaxis theory. Consequently, accounting for these effects could lead to a better understanding of tissue generation in vivo, and result in more advanced engineered tissue products in vitro.
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Affiliation(s)
- Quang Long Pham
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Lydia N Rodrigues
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Max A Maximov
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Vishnu Deep Chandran
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Cheng Bi
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - David Chege
- Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Timothy Dijamco
- Computer Science Dept., New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Elisabeth Stein
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Nhat Anh Nguyen Tong
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Sagnik Basuray
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
| | - Roman S Voronov
- Otto H. York Department of Chemical and Materials Engineering, New Jersey Institute of Technology, Newark, NJ 07102 USA
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19
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Ellett F, Jorgensen J, Marand AL, Liu YM, Martinez MM, Sein V, Butler KL, Lee J, Irimia D. Diagnosis of sepsis from a drop of blood by measurement of spontaneous neutrophil motility in a microfluidic assay. Nat Biomed Eng 2018; 2:207-214. [PMID: 30283724 DOI: 10.1038/s41551-018-0208-z] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Current methods for the diagnosis of sepsis have insufficient precision, causing regular misdiagnoses. Microbiological tests can help diagnose sepsis but are usually too slow to have an impact on timely clinical-decision making. Neutrophils have high sensitivity to infections, yet measurements of neutrophil surface markers, genomic changes, and phenotype alterations have had only a marginal effect on sepsis diagnosis. Here, we report a microfluidic assay that measures the spontaneous motility of neutrophils in the context of plasma, in one droplet of blood. We measured the performance of the assay in two independent cohorts of critically ill patients suspected of sepsis. In the first cohort, we developed a machine-learning-based scoring system (sepsis score) that segregated patients with sepsis from those without sepsis. In the second cohort, we validated the sepsis score in a double-blinded, prospective case-control study. For the 42 patients across the two cohorts, the assay identified sepsis patients with 97% sensitivity and 98% specificity. The neutrophil assay could potentially be used to accurately diagnose and monitor sepsis in larger populations of at-risk patients.
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Affiliation(s)
- Felix Ellett
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA.,Shriners Burns Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA.,Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Julianne Jorgensen
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA.,Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Anika L Marand
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA.,Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Yuk Ming Liu
- Shriners Burns Hospital, Boston, MA, USA.,Harvard Medical School, Boston, MA, USA.,Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Myriam M Martinez
- Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Vicki Sein
- Harvard Medical School, Boston, MA, USA.,Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Kathryn L Butler
- Harvard Medical School, Boston, MA, USA.,Department of Surgery, Massachusetts General Hospital, Boston, MA, USA
| | - Jarone Lee
- Harvard Medical School, Boston, MA, USA.,Department of Surgery, Massachusetts General Hospital, Boston, MA, USA.,Department of Emergency Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Daniel Irimia
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA, USA. .,Shriners Burns Hospital, Boston, MA, USA. .,Harvard Medical School, Boston, MA, USA. .,Department of Surgery, Massachusetts General Hospital, Boston, MA, USA.
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20
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Boneschansker L, Jorgensen J, Ellett F, Briscoe DM, Irimia D. Convergent and Divergent Migratory Patterns of Human Neutrophils inside Microfluidic Mazes. Sci Rep 2018; 8:1887. [PMID: 29382882 PMCID: PMC5789854 DOI: 10.1038/s41598-018-20060-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 12/19/2017] [Indexed: 12/30/2022] Open
Abstract
Neutrophils are key cellular components of the innate immune response and characteristically migrate from the blood towards and throughout tissues. Their migratory process is complex, guided by multiple chemoattractants released from injured tissues and microbes. How neutrophils integrate the various signals in the tissue microenvironment and mount effective responses is not fully understood. Here, we employed microfluidic mazes that replicate features of interstitial spaces and chemoattractant gradients within tissues to analyze the migration patterns of human neutrophils. We find that neutrophils respond to LTB4 and fMLF gradients with highly directional migration patterns and converge towards the source of chemoattractant. We named this directed migration pattern convergent. Moreover, neutrophils respond to gradients of C5a and IL-8 with a low-directionality migration pattern and disperse within mazes. We named this alternative migration pattern divergent. Inhibitors of MAP kinase and PI-3 kinase signaling pathways do not alter either convergent or divergent migration patterns, but reduce the number of responding neutrophils. Overlapping gradients of chemoattractants conserve the convergent and divergent migration patterns corresponding to each chemoattractant and have additive effects on the number of neutrophils migrating. These results suggest that convergent and divergent neutrophil migration-patterns are the result of simultaneous activation of multiple signaling pathways.
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Affiliation(s)
- Leo Boneschansker
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA, USA.,Transplant Research Program and The Division of Nephrology, Department of Medicine, Boston Children's Hospital, Boston, MA, USA.,Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Julianne Jorgensen
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA, USA
| | - Felix Ellett
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA, USA
| | - David M Briscoe
- Transplant Research Program and The Division of Nephrology, Department of Medicine, Boston Children's Hospital, Boston, MA, USA.,Department of Pediatrics, Harvard Medical School, Boston, MA, USA
| | - Daniel Irimia
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Hospitals for Children, Boston, MA, USA.
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21
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Yang K, Wu J, Zhu L, Liu Y, Zhang M, Lin F. An All-on-chip Method for Rapid Neutrophil Chemotaxis Analysis Directly from a Drop of Blood. J Vis Exp 2017. [PMID: 28671651 DOI: 10.3791/55615] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Neutrophil migration and chemotaxis are critical for our body's immune system. Microfluidic devices are increasingly used for investigating neutrophil migration and chemotaxis owing to their advantages in real-time visualization, precise control of chemical concentration gradient generation, and reduced reagent and sample consumption. Recently, a growing effort has been made by the microfluidic researchers toward developing integrated and easily operated microfluidic chemotaxis analysis systems, directly from whole blood. In this direction, the first all-on-chip method was developed for integrating the magnetic negative purification of neutrophils and the chemotaxis assay from small blood volume samples. This new method permits a rapid sample-to-result neutrophil chemotaxis test in 25 min. In this paper, we provide detailed construction, operation and data analysis method for this all-on-chip chemotaxis assay with a discussion on troubleshooting strategies, limitations and future directions. Representative results of the neutrophil chemotaxis assay testing a defined chemoattractant, N-Formyl-Met-Leu-Phe (fMLP), and sputum from a chronic obstructive pulmonary disease (COPD) patient, using this all-on-chip method are shown. This method is applicable to many cell migration-related investigations and clinical applications.
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Affiliation(s)
- Ke Yang
- Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences; University of Science and Technology of China; Department of Physics and Astronomy, University of Manitoba
| | - Jiandong Wu
- Department of Physics and Astronomy, University of Manitoba; Department of Biosystems Engineering, University of Manitoba
| | - Ling Zhu
- Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences
| | - Yong Liu
- Institute of Applied Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences
| | | | - Francis Lin
- Department of Physics and Astronomy, University of Manitoba; Department of Biosystems Engineering, University of Manitoba; Department of Immunology, University of Manitoba; Department of Biological Sciences, University of Manitoba;
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22
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Roy J, Mazzaferri J, Filep JG, Costantino S. A Haptotaxis Assay for Neutrophils using Optical Patterning and a High-content Approach. Sci Rep 2017; 7:2869. [PMID: 28588217 PMCID: PMC5460230 DOI: 10.1038/s41598-017-02993-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Accepted: 04/21/2017] [Indexed: 12/30/2022] Open
Abstract
Neutrophil recruitment guided by chemotactic cues is a central event in host defense against infection and tissue injury. While the mechanisms underlying neutrophil chemotaxis have been extensively studied, these are just recently being addressed by using high-content approaches or surface-bound chemotactic gradients (haptotaxis) in vitro. Here, we report a haptotaxis assay, based on the classic under-agarose assay, which combines an optical patterning technique to generate surface-bound formyl peptide gradients as well as an automated imaging and analysis of a large number of migration trajectories. We show that human neutrophils migrate on covalently-bound formyl-peptide gradients, which influence the speed and frequency of neutrophil penetration under the agarose. Analysis revealed that neutrophils migrating on surface-bound patterns accumulate in the region of the highest peptide concentration, thereby mimicking in vivo events. We propose the use of a chemotactic precision index, gyration tensors and neutrophil penetration rate for characterizing haptotaxis. This high-content assay provides a simple approach that can be applied for studying molecular mechanisms underlying haptotaxis on user-defined gradient shape.
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Affiliation(s)
- Joannie Roy
- Research Center, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada.,Biomedical Engineering Institute, University of Montreal, Montreal, Quebec, Canada
| | - Javier Mazzaferri
- Research Center, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada
| | - János G Filep
- Research Center, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada.,Department of Pathology and Cell Biology, University of Montreal, Montreal, Quebec, Canada
| | - Santiago Costantino
- Research Center, Maisonneuve-Rosemont Hospital, Montreal, Quebec, Canada. .,Biomedical Engineering Institute, University of Montreal, Montreal, Quebec, Canada. .,Department of Ophthalmology, University of Montreal, Montreal, Quebec, Canada.
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23
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Abstract
Chemotaxis and autochemotaxis play an important role in many essential biological processes. We present a self-propelling artificial swimmer system that exhibits chemotaxis as well as negative autochemotaxis. Oil droplets in an aqueous surfactant solution are driven by interfacial Marangoni flows induced by micellar solubilization of the oil phase. We demonstrate that chemotaxis along micellar surfactant gradients can guide these swimmers through a microfluidic maze. Similarly, a depletion of empty micelles in the wake of a droplet swimmer causes negative autochemotaxis and thereby trail avoidance. We studied autochemotaxis quantitatively in a microfluidic device of bifurcating channels: Branch choices of consecutive swimmers are anticorrelated, an effect decaying over time due to trail dispersion. We modeled this process by a simple one-dimensional diffusion process and stochastic Langevin dynamics. Our results are consistent with a linear surfactant gradient force and diffusion constants appropriate for micellar diffusion and provide a measure of autochemotactic feedback strength vs. stochastic forces. This assay is readily adaptable for quantitative studies of both artificial and biological autochemotactic systems.
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24
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25
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Chiu DT, deMello AJ, Di Carlo D, Doyle PS, Hansen C, Maceiczyk RM, Wootton RC. Small but Perfectly Formed? Successes, Challenges, and Opportunities for Microfluidics in the Chemical and Biological Sciences. Chem 2017. [DOI: 10.1016/j.chempr.2017.01.009] [Citation(s) in RCA: 212] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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26
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Jain NG, Wong EA, Aranyosi AJ, Boneschansker L, Markmann JF, Briscoe DM, Irimia D. Microfluidic mazes to characterize T-cell exploration patterns following activation in vitro. Integr Biol (Camb) 2016; 7:1423-31. [PMID: 26325525 DOI: 10.1039/c5ib00146c] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The migration of T-cell subsets within peripheral tissues is characteristic of inflammation and immunoregulation. In general, the lymphocyte migratory response is assumed directional and guided by local gradients of chemoattractants and/or chemorepellents. However, little is known about how cells explore their tissue environment, and whether lymphocyte activation may influence speed and exploratory patterns of migration. To probe migration patterns by T-cells we designed a microfluidic maze device that replicates critical features of a tissue-like microenvironment. We quantified the migration patterns of unstimulated and mitogen-activated human T-cells at single cell resolution and found significant differences in exploration within microfluidic mazes. While unstimulated lymphocytes migrated in a directed manner, activated T-cells migrated through large areas of the mazes in an exploratory pattern in response to the chemoattractants RANTES (CCL5) and IP-10 (CXCL10). The analysis of migration enabled by the microfluidic devices help develop new methods for determining how human circulating T-cells function in vivo to seek out antigens in health and disease states.
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Affiliation(s)
- Namrata G Jain
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA 02129, USA and Transplant Research Program, Boston Children's Hospital, Boston, MA 02115, USA.
| | - Elisabeth A Wong
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA 02129, USA
| | - Alexander J Aranyosi
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA 02129, USA
| | - Leo Boneschansker
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA 02129, USA and Transplant Research Program, Boston Children's Hospital, Boston, MA 02115, USA.
| | - James F Markmann
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA 02129, USA and Division of Nephrology, Department of Medicine, Boston Children's Hospital, 300 Longwood Ave, MA 02139, USA
| | - David M Briscoe
- Transplant Research Program, Boston Children's Hospital, Boston, MA 02115, USA. and Division of Nephrology, Department of Medicine, Boston Children's Hospital, 300 Longwood Ave, MA 02139, USA
| | - Daniel Irimia
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Boston, MA 02129, USA and Harvard Medical School, Boston, MA 02129, USA.
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27
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Abstract
Cells in the body are physically confined by neighboring cells, tissues, and the extracellular matrix. Although physical confinement modulates intracellular signaling and the underlying mechanisms of cell migration, it is difficult to study in vivo. Furthermore, traditional two-dimensional cell migration assays do not recapitulate the complex topographies found in the body. Therefore, a number of experimental in vitro models that confine and impose forces on cells in well-defined microenvironments have been engineered. We describe the design and use of microfluidic microchannel devices, grooved substrates, micropatterned lines, vertical confinement devices, patterned hydrogels, and micropipette aspiration assays for studying cell responses to confinement. Use of these devices has enabled the delineation of changes in cytoskeletal reorganization, cell-substrate adhesions, intracellular signaling, nuclear shape, and gene expression that result from physical confinement. These assays and the physiologically relevant signaling pathways that have been elucidated are beginning to have a translational and clinical impact.
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Affiliation(s)
- Colin D Paul
- Department of Chemical and Biomolecular Engineering
- Institute for NanoBioTechnology, and
| | - Wei-Chien Hung
- Department of Chemical and Biomolecular Engineering
- Institute for NanoBioTechnology, and
| | - Denis Wirtz
- Department of Chemical and Biomolecular Engineering
- Institute for NanoBioTechnology, and
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21218;
| | - Konstantinos Konstantopoulos
- Department of Chemical and Biomolecular Engineering
- Institute for NanoBioTechnology, and
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21218;
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28
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Irimia D, Ellett F. Big insights from small volumes: deciphering complex leukocyte behaviors using microfluidics. J Leukoc Biol 2016; 100:291-304. [PMID: 27194799 DOI: 10.1189/jlb.5ru0216-056r] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Accepted: 04/04/2016] [Indexed: 12/13/2022] Open
Abstract
Inflammation is an indispensable component of the immune response, and leukocytes provide the first line of defense against infection. Although the major stereotypic leukocyte behaviors in response to infection are well known, the complexities and idiosyncrasies of these phenotypes in conditions of disease are still emerging. Novel tools are indispensable for gaining insights into leukocyte behavior, and in the past decade, microfluidic technologies have emerged as an exciting development in the field. Microfluidic devices are readily customizable, provide tight control of experimental conditions, enable high precision of ex vivo measurements of individual as well as integrated leukocyte functions, and have facilitated the discovery of novel leukocyte phenotypes. Here, we review some of the most interesting insights resulting from the application of microfluidic approaches to the study of the inflammatory response. The aim is to encourage leukocyte biologists to integrate these new tools into increasingly more sophisticated experimental designs for probing complex leukocyte functions.
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Affiliation(s)
- Daniel Irimia
- BioMEMS Resource Center, Division of Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Burns Hospital, Boston, Massachusetts, USA
| | - Felix Ellett
- BioMEMS Resource Center, Division of Surgery, Innovation and Bioengineering, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Shriners Burns Hospital, Boston, Massachusetts, USA
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29
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Cytoskeletal Symmetry Breaking and Chirality: From Reconstituted Systems to Animal Development. Symmetry (Basel) 2015. [DOI: 10.3390/sym7042062] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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30
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Paredes R, Ishibashi S, Borrill R, Robert J, Amaya E. Xenopus: An in vivo model for imaging the inflammatory response following injury and bacterial infection. Dev Biol 2015; 408:213-28. [PMID: 25823652 PMCID: PMC4685038 DOI: 10.1016/j.ydbio.2015.03.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Revised: 03/05/2015] [Accepted: 03/10/2015] [Indexed: 11/05/2022]
Abstract
A major goal in regenerative medicine is to identify therapies to facilitate our body׳s innate abilities to repair and regenerate following injury, disease or aging. In the past decade it has become apparent that the innate immune system is able to affect the speed and quality of the regenerative response through mechanisms that are not entirely clear. For this reason there has been a resurgent interest in investigating the role of inflammation during tissue repair and regeneration. Remarkably, there have only been a handful of such studies using organisms with high regenerative capacity. Here we perform a study of the inflammatory response following injury in Xenopus larvae, which are able to achieve scarless wound healing and to regenerate appendages, as a preamble into understanding the role that inflammation plays during tissue repair and regeneration in this organism. We characterized the morphology and migratory behavior of granulocytes and macrophages following sterile and infected wounding regimes, using various transgenic lines that labeled different types of myeloid lineages, including granulocytes and macrophages. Using this approach we found that the inflammatory response following injury and infection in Xenopus larvae is very similar to that seen in humans, suggesting that this model provides an easily tractable and medically relevant system to investigate inflammation following injury and infection in vivo. Xenopus larvae is an ideal model to study injury-induced inflammation in vivo. Xenopus larvae provides an easily tractable model of human inflammation. Xenopus larvae provides a powerful model for investigating cell migration in vivo.
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Affiliation(s)
- Roberto Paredes
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom; The Healing Foundation Centre, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom
| | - Shoko Ishibashi
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom; The Healing Foundation Centre, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom
| | - Roisin Borrill
- The Healing Foundation Centre, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom
| | - Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, 601 Elmwood Ave, Rochester, NY 14642, USA
| | - Enrique Amaya
- Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom; The Healing Foundation Centre, University of Manchester, Oxford Road, Manchester M13 9PT, United Kingdom.
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31
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Gopalakrishnan N, Hannam R, Casoni GP, Barriet D, Ribe JM, Haug M, Halaas Ø. Infection and immunity on a chip: a compartmentalised microfluidic platform to monitor immune cell behaviour in real time. LAB ON A CHIP 2015; 15:1481-1487. [PMID: 25608968 DOI: 10.1039/c4lc01438c] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Cells respond to their environments and self-organise into multicellular assemblies with dedicated functions. The migratory and homing response of cells to soluble ligands can be studied by using different techniques, but for real time studies of complex multicellular self-organisation, novel and simpler systems are required. We fabricated a flexible open access microsystem and tested the design by studying cell recruitment from an immune cell reservoir towards an infectious compartment. The two compartments were connected by a network of bifurcated microchannels allowing diffusion of signalling molecules and migration of cells. Bacterial filters were incorporated in the design to prevent bacteria and activated cells from entering the network, permitting migration only from the recruitment reservoir. The fabricated microsystem allows real-time continuous monitoring of cellular decision-making based on biologically produced gradients of cytokines and chemokines. It is a valuable tool for studying cellular migration and self-organisation in relation to infections, autoimmunity, cancer, stem cell homing, and tissue and wound repair.
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Affiliation(s)
- N Gopalakrishnan
- Dept. of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, 7489 Trondheim, Norway.
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32
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Confinement dependent chemotaxis in two-photon polymerized linear migration constructs with highly definable concentration gradients. Biomed Microdevices 2015; 17:30. [DOI: 10.1007/s10544-015-9937-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Aranyosi AJ, Wong EA, Irimia D. A neutrophil treadmill to decouple spatial and temporal signals during chemotaxis. LAB ON A CHIP 2015; 15:549-556. [PMID: 25412288 PMCID: PMC4268067 DOI: 10.1039/c4lc00970c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
After more than 50 years of debates, the role of spatial and temporal gradients during cell chemotaxis is still a contentious matter. One major challenge is that when cells move in response to a heterogeneous chemical environment they are exposed to both spatial and temporal concentration changes. Even in the presence of perfectly stable chemical gradients, moving cells experience temporal changes of concentration simply by moving between locations with different chemical concentrations in a heterogeneous environment. Thus, the effects of the spatial and temporal stimuli cannot be dissociated and studied independently, hampering progress towards understanding the mechanisms of cell chemotaxis. Here we employ microfluidic and other engineering tools to build a system that accomplishes a function analogous to a treadmill at the cellular scale, holding a moving cell at a specified, unchanging location in a chemical gradient. Using this system, we decouple the spatial and temporal gradients around moving human neutrophils and find that temporal gradients are necessary for the directional persistence of human neutrophils during chemotaxis. Our results suggest that temporal chemoattractant changes are important during neutrophil migration and should be taken into account when deciphering the signalling pathways of cell chemotaxis.
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Affiliation(s)
- Alexander J. Aranyosi
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Charlestown MA 02129
| | - Elisabeth A. Wong
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Charlestown MA 02129
| | - Daniel Irimia
- BioMEMS Resource Center, Department of Surgery, Massachusetts General Hospital, Harvard Medical School, Charlestown MA 02129
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Jones CN, Moore M, Dimisko L, Alexander A, Ibrahim A, Hassell BA, Warren HS, Tompkins RG, Fagan SP, Irimia D. Spontaneous neutrophil migration patterns during sepsis after major burns. PLoS One 2014; 9:e114509. [PMID: 25489947 PMCID: PMC4260850 DOI: 10.1371/journal.pone.0114509] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 11/09/2014] [Indexed: 02/07/2023] Open
Abstract
Finely tuned to respond quickly to infections, neutrophils have amazing abilities to migrate fast and efficiently towards sites of infection and inflammation. Although neutrophils ability to migrate is perturbed in patients after major burns, no correlations have yet been demonstrated between altered migration and higher rate of infections and sepsis in these patients when compared to healthy individuals. To probe if such correlations exist, we designed microfluidic devices to quantify the neutrophil migration phenotype with high precision. Inside these devices, moving neutrophils are confined in channels smaller than the neutrophils and forced to make directional decisions at bifurcations and around posts. We employed these devices to quantify neutrophil migration across 18 independent parameters in 74 blood samples from 13 patients with major burns and 3 healthy subjects. Blinded, retrospective analysis of clinical data and neutrophil migration parameters revealed that neutrophils isolated from blood samples collected during sepsis migrate spontaneously inside the microfluidic channels. The spontaneous neutrophil migration is a unique phenotype, typical for patients with major burns during sepsis and often observed one or two days before the diagnosis of sepsis is confirmed. The spontaneous neutrophil migration phenotype is rare in patients with major burns in the absence of sepsis, and is not encountered in healthy individuals. Our findings warrant further studies of neutrophils and their utility for early diagnosing and monitoring sepsis in patients after major burns.
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Affiliation(s)
- Caroline N. Jones
- Surgery Department, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- BioMEMS Resource Center, Center for Engineering in Medicine and Surgical Services, Boston, Massachusetts, United States of America
- Shriners Hospital for Children, Boston, Massachusetts, United States of America
| | - Molly Moore
- Surgery Department, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Laurie Dimisko
- Surgery Department, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- BioMEMS Resource Center, Center for Engineering in Medicine and Surgical Services, Boston, Massachusetts, United States of America
| | - Andrew Alexander
- Surgery Department, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Amir Ibrahim
- Surgery Department, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- Shriners Hospital for Children, Boston, Massachusetts, United States of America
| | - Bryan A. Hassell
- BioMEMS Resource Center, Center for Engineering in Medicine and Surgical Services, Boston, Massachusetts, United States of America
| | - H. Shaw Warren
- Shriners Hospital for Children, Boston, Massachusetts, United States of America
- Departments of Pediatrics and Medicine, Infectious Disease Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Ronald G. Tompkins
- Surgery Department, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Shawn P. Fagan
- Surgery Department, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
| | - Daniel Irimia
- Surgery Department, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, United States of America
- BioMEMS Resource Center, Center for Engineering in Medicine and Surgical Services, Boston, Massachusetts, United States of America
- Shriners Hospital for Children, Boston, Massachusetts, United States of America
- * E-mail:
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Hamza B, Wong E, Patel S, Cho H, Martel J, Irimia D. Retrotaxis of human neutrophils during mechanical confinement inside microfluidic channels. Integr Biol (Camb) 2014; 6:175-83. [PMID: 24419464 DOI: 10.1039/c3ib40175h] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The current paradigm of unidirectional migration of neutrophils from circulation to sites of injury in tissues has been recently challenged by observations in zebrafish showing that neutrophils can return from tissues back into the circulation. However, the relevance of these observations to human neutrophils remains unclear, the forward and reverse migration of neutrophils is difficult to quantify, and the precise conditions modulating the reverse migration cannot be isolated. Here, we designed a microfluidic platform inside which we observed human neutrophil migration in response to chemoattractant sources inside channels, simulating the biochemical and mechanical confinement conditions at sites of injury in tissues. We observed that, after initially following the direction of chemoattractant gradients, more than 90% of human neutrophils can reverse their direction and migrate persistently and for distances longer than one thousand micrometers away from chemoattractant sources (retrotaxis). Retrotaxis is enhanced in the presence of lipoxin A4 (LXA4), a well-established mediator of inflammation resolution, or Tempol, a standard antioxidant. Retrotaxis stops after neutrophils encounter targets which they phagocytise or on surfaces presenting high concentrations of fibronectin. Our microfluidic model suggests a new paradigm for neutrophil accumulation at sites of inflammation, which depends on the balance of three simultaneous processes: chemotaxis along diffusion gradients, retrotaxis following mechanical guides, and stopping triggered by phagocytosis.
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Affiliation(s)
- Bashar Hamza
- BioMEMS Resource Center, Massachusetts General Hospital, Harvard Medical School, and Shriners Hospital for Children, Charlestown, MA 02129, USA.
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Berthier E, Beebe DJ. Gradient generation platforms: new directions for an established microfluidic technology. LAB ON A CHIP 2014; 14:3241-7. [PMID: 25008971 PMCID: PMC4134926 DOI: 10.1039/c4lc00448e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Microscale platforms are enabling for cell-based studies as they allow the recapitulation of physiological conditions such as extracellular matrix (ECM) configurations and soluble factors interactions. Gradient generation platforms have been one of the few applications of microfluidics that have begun to be translated to biological laboratories and may become a new "gold standard". Though gradient generation platforms are now established, their full potential has not yet been realized. Here, we will provide our perspective on milestones achieved in the development of gradient generation and cell migration platforms, as well as emerging directions such as using cell migration as a diagnostic readout and attaining mechanistic information from cell migration models.
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Affiliation(s)
- E Berthier
- Microtechnology Medicine and Biology Lab (MMB), Department of Biomedical Engineering, University of Wisconsin-Madison, USA.
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Microfluidic platform for the quantitative analysis of leukocyte migration signatures. Nat Commun 2014; 5:4787. [PMID: 25183261 PMCID: PMC4155519 DOI: 10.1038/ncomms5787] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Accepted: 07/24/2014] [Indexed: 12/22/2022] Open
Abstract
Leukocyte migration into tissues is characteristic of inflammation. It is usually measured in vitro as the average displacement of populations of cells towards a chemokine gradient, not acknowledging other patterns of cell migration. Here, we designed and validated a microfluidic migration platform to simultaneously analyze four qualitative migration patterns: chemo-attraction, -repulsion, -kinesis and -inhibition, using single-cell quantitative metrics of direction, speed, persistence, and fraction of cells responding. We find that established chemokines C5a and IL-8 induce chemoattraction and repulsion in equal proportions, resulting in the dispersal of cells. These migration signatures are characterized by high persistence and speed and are independent of the chemokine dose or receptor expression. Furthermore, we find that twice as many T-lymphocytes migrate away than towards SDF-1 and their directional migration patterns are not persistent. Overall, our platform characterizes migratory signature responses and uncovers an avenue for precise characterization of leukocyte migration and therapeutic modulators.
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38
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Microfluidic platform to evaluate migration of cells from patients with DYT1 dystonia. J Neurosci Methods 2014; 232:181-188. [PMID: 24880044 DOI: 10.1016/j.jneumeth.2014.05.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 05/11/2014] [Accepted: 05/20/2014] [Indexed: 01/05/2023]
Abstract
BACKGROUND Microfluidic platforms for quantitative evaluation of cell biologic processes allow low cost and time efficient research studies of biological and pathological events, such as monitoring cell migration by real-time imaging. In healthy and disease states, cell migration is crucial in development and wound healing, as well as to maintain the body's homeostasis. NEW METHOD The microfluidic chambers allow precise measurements to investigate whether fibroblasts carrying a mutation in the TOR1A gene, underlying the hereditary neurologic disease--DYT1 dystonia, have decreased migration properties when compared to control cells. RESULTS We observed that fibroblasts from DYT1 patients showed abnormalities in basic features of cell migration, such as reduced velocity and persistence of movement. COMPARISON WITH EXISTING METHOD The microfluidic method enabled us to demonstrate reduced polarization of the nucleus and abnormal orientation of nuclei and Golgi inside the moving DYT1 patient cells compared to control cells, as well as vectorial movement of single cells. CONCLUSION We report here different assays useful in determining various parameters of cell migration in DYT1 patient cells as a consequence of the TOR1A gene mutation, including a microfluidic platform, which provides a means to evaluate real-time vectorial movement with single cell resolution in a three-dimensional environment.
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39
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Junkin M, Tay S. Microfluidic single-cell analysis for systems immunology. LAB ON A CHIP 2014; 14:1246-60. [PMID: 24503696 DOI: 10.1039/c3lc51182k] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The immune system constantly battles infection and tissue damage, but exaggerated immune responses lead to allergies, autoimmunity and cancer. Discrimination of self from foreign and the fine-tuning of immunity are achieved by information processing pathways, whose regulatory mechanisms are little understood. Cell-to-cell variability and stochastic molecular interactions result in diverse cellular responses to identical signaling inputs, casting doubt on the reliability of traditional population-averaged analyses. Furthermore, dynamic molecular and cellular interactions create emergent properties that change over multiple time scales. Understanding immunity in the face of complexity and noisy dynamics requires time-dependent analysis of single-cells in a proper context. Microfluidic systems create precisely defined microenvironments by controlling fluidic and surface chemistries, feature sizes, geometries and signal input timing, and thus enable quantitative multi-parameter analysis of single cells. Such qualities allow observable dynamic environments approaching in vivo levels of biological complexity. Seamless parallelization of functional units in microfluidic devices allows high-throughput measurements, an essential feature for statistically meaningful analysis of naturally variable biological systems. These abilities recapitulate diverse scenarios such as cell-cell signaling, migration, differentiation, antibody and cytokine production, clonal selection, and cell lysis, thereby enabling accurate and meaningful study of immune behaviors in vitro.
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Affiliation(s)
- Michael Junkin
- Department of Biosystems Science and Engineering, ETH Zürich, Switzerland.
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40
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Mak M, Erickson D. Mechanical decision trees for investigating and modulating single-cell cancer invasion dynamics. LAB ON A CHIP 2014; 14:964-71. [PMID: 24425041 PMCID: PMC4656028 DOI: 10.1039/c3lc51173a] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Physical cues exist across all biological scales, from the geometries of molecules to the shapes of complex organisms. While their roles have been identified across a range of scales, i.e. the arrangements of biomolecules and the form and function of tissues, less is known in some intermediate lengths. Particularly, at the cell scale, there is emerging evidence demonstrating the impact of mechanical signals, such as substrate stiffness and confinement, on many critical biological processes and malignancies, especially cancer dissemination. In the context of cell invasion, it is currently unclear how cells select from accessible mechanical paths that result in migratory patterns observed in physiological environments. Here, we devise microchannel decision trees to explore how fundamental and ubiquitous mechanical factors, specifically dimensionality and directionality, affect migratory cell decision making. We then implement strategies based purely on mechanical asymmetries to induce repetitive, non-disseminating motions, in a phenomenon we call iteratio ad nauseam.
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Affiliation(s)
- Michael Mak
- Biomedical Engineering Department, Cornell University, Ithaca, NY 14853, USA
| | - David Erickson
- Sibley School of Mechanical and Aerospace Engineering, Cornell University, 240 Upson Hall, Ithaca, NY 14853, USA
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41
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Baratchi S, Khoshmanesh K, Sacristán C, Depoil D, Wlodkowic D, McIntyre P, Mitchell A. Immunology on chip: Promises and opportunities. Biotechnol Adv 2014; 32:333-46. [DOI: 10.1016/j.biotechadv.2013.11.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 11/04/2013] [Accepted: 11/17/2013] [Indexed: 01/09/2023]
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Lämmermann T, Germain RN. The multiple faces of leukocyte interstitial migration. Semin Immunopathol 2014; 36:227-51. [PMID: 24573488 DOI: 10.1007/s00281-014-0418-8] [Citation(s) in RCA: 118] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 01/26/2014] [Indexed: 12/22/2022]
Abstract
Spatiotemporal control of leukocyte dynamics within tissues is critical for successful innate and adaptive immune responses. Homeostatic trafficking and coordinated infiltration into and within sites of inflammation and infection rely on signaling in response to extracellular cues that in turn controls a variety of intracellular protein networks regulating leukocyte motility, migration, chemotaxis, positioning, and cell-cell interaction. In contrast to mesenchymal cells, leukocytes migrate in an amoeboid fashion by rapid cycles of actin polymerization and actomyosin contraction, and their migration in tissues is generally referred to as low adhesive and nonproteolytic. The interplay of actin network expansion, contraction, and adhesion shapes the exact mode of amoeboid migration, and in this review, we explore how leukocyte subsets potentially harness the same basic biomechanical mechanisms in a cell-type-specific manner. Most of our detailed understanding of these processes derives from in vitro migration studies in three-dimensional gels and confined spaces that mimic geometrical aspects of physiological tissues. We summarize these in vitro results and then critically compare them to data from intravital imaging of leukocyte interstitial migration in mouse tissues. We outline the technical challenges of obtaining conclusive mechanistic results from intravital studies, discuss leukocyte migration strategies in vivo, and present examples of mode switching during physiological interstitial migration. These findings are also placed in the context of leukocyte migration defects in primary immunodeficiencies. This overview of both in vitro and in vivo studies highlights recent progress in understanding the molecular and biophysical mechanisms that shape robust leukocyte migration responses in physiologically complex and heterogeneous environments.
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Affiliation(s)
- Tim Lämmermann
- Laboratory of Systems Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA,
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43
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Hanlon SD, Smith CW, Sauter MN, Burns AR. Integrin-dependent neutrophil migration in the injured mouse cornea. Exp Eye Res 2014; 120:61-70. [PMID: 24462632 DOI: 10.1016/j.exer.2014.01.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 12/12/2013] [Accepted: 01/04/2014] [Indexed: 12/25/2022]
Abstract
As an early responder to an inflammatory stimulus, neutrophils (PMNs) must exit the vasculature and migrate through the extravascular tissue to the site of insult, which is often remote from the point of extravasation. Following a central epithelial corneal abrasion, PMNs recruited from the peripheral limbal vasculature migrate into the avascular corneal stroma. In vitro studies suggest PMN locomotion over 2-D surfaces is dependent on integrin binding while migration within 3-D matrices can be integrin-independent. Electron micrographs of injured mouse corneas show migrating PMNs make extensive surface contact not only with collagen fibrils in the extracellular matrix (ECM), but also keratocytes. Evidence supporting involvement of integrins in corneal inflammation has prompted research and development of integrin blocking agents for use as anti-inflammatory therapies. However, the role of integrin binding (cell-cell; cell-ECM) during stromal migration in the inflamed cornea has previously not been clearly defined. In this study in vivo time lapse imaging sequences provided the means to quantify cell motility while observing PMN interactions with keratocytes and other stromal components in the living eye. The relative contribution of β1, β2 and β3 integrins to PMN locomotion in the inflamed mouse cornea was investigated using blocking antibodies against the respective integrins. Of the 3 integrin families (β1, β2 and β3) investigated for their potential role in PMN migration, only β1 antibody blockade produced a significant, but partial, reduction in PMN motility. The preferential migration of PMNs along the keratocyte network was not affected by integrin blockade. Hence, the dominant mechanism for PMN motility within the corneal stroma appears to be integrin-independent as does the restriction of PMN migration paths to the keratocyte network.
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Affiliation(s)
- Samuel D Hanlon
- College of Optometry, University of Houston, Houston, TX, USA.
| | - C Wayne Smith
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
| | - Marika N Sauter
- College of Optometry, University of Houston, Houston, TX, USA
| | - Alan R Burns
- College of Optometry, University of Houston, Houston, TX, USA; Department of Pediatrics, Baylor College of Medicine, Houston, TX, USA
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44
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Sip CG, Bhattacharjee N, Folch A. Microfluidic transwell inserts for generation of tissue culture-friendly gradients in well plates. LAB ON A CHIP 2014; 14:302-14. [PMID: 24225908 PMCID: PMC4362725 DOI: 10.1039/c3lc51052b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Gradients of biochemical molecules play a key role in many physiological processes such as axon growth, tissue morphogenesis, and trans-epithelium nutrient transport, as well as in pathophysiological phenomena such as wound healing, immune response, bacterial invasion, and cancer metastasis. In this paper, we report a microfluidic transwell insert for generating quantifiable concentration gradients in a user-friendly and modular format that is compatible with conventional cell cultures and with tissue explant cultures. The device is simply inserted into a standard 6-well plate, where it hangs self-supported at a distance of ~250 μm above the cell culture surface. The gradient is created by small microflows from the device, through an integrated track-etched porous membrane, into the cell culture well. The microfluidic transwell can deliver stable, quantifiable gradients over a large area with extremely low fluid shear stress to dissociated cells or tissue explants cultured independently on the surface of a 6-well plate. We used finite-element modeling to describe the porous membrane flow and molecular transport and to predict gradients generated by the device. Using the device, we applied a gradient of the chemotactic peptide N-formyl-met-leu-phe (fMLP) to a large population of HL-60 cells (a neutrophil cell line) and directly observed the migration with time-lapse microscopy. On quantification of the chemotactic response with an automated tracking algorithm, we found 74% of the cells moving towards the gradient. Additionally, the modular design and low fluid shear stress made it possible to apply gradients of growth factors and second messengers to mouse retinal explant cultures. With a simplified interface and well-defined gradients, the microfluidic transwell device has potential for broad applications to gradient-sensing biology.
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Affiliation(s)
- Christopher G Sip
- Bioengineering, University of Washington, William H. Foege Building, 1705 NE Pacific St. Campus Box 355061, Seattle, Washington, USA.
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45
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Abstract
We describe a protocol for measuring the speed of human neutrophils migrating through small channels, in conditions of mechanical confinement comparable to those experienced by neutrophils migrating through tissues. In such conditions, we find that neutrophils move persistently, at constant speed for tens of minutes, enabling precise measurements at single cells resolution, for large number of cells. The protocol relies on microfluidic devices with small channels in which a solution of chemoattractant and a suspension of isolated neutrophils are loaded in sequence. The migration of neutrophils can be observed for several hours, starting within minutes after loading the neutrophils in the devices. The protocol is divided into four main steps: the fabrication of the microfluidic devices, the separation of neutrophils from whole blood, the preparation of the assay and cell loading, and the analysis of data. We discuss the practical steps for the implementation of the migration assays in biology labs, the adaptation of the protocols to various cell types, including cancer cells, and the supplementary device features required for precise measurements of directionality and persistence during migration.
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Affiliation(s)
- Daniel Irimia
- Massachusetts General Hospital, Harvard Medical School, and Shirners Hospitals for Children, Boston, Massachusetts, USA
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46
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Olsen MH, Hjortø GM, Hansen M, Met Ö, Svane IM, Larsen NB. In-chip fabrication of free-form 3D constructs for directed cell migration analysis. LAB ON A CHIP 2013; 13:4800-9. [PMID: 24153393 DOI: 10.1039/c3lc50930c] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Free-form constructs with three-dimensional (3D) microporosity were fabricated by two-photon polymerization inside the closed microchannel of an injection-molded, commercially available polymer chip for analysis of directed cell migration. Acrylate constructs were produced as woodpile topologies with a range of pore sizes from 5 × 5 μm to 15 × 15 μm and prefilled with fibrillar collagen. Dendritic cells seeded into the polymer chip in a concentration gradient of the chemoattractant CCL21 efficiently negotiated the microporous maze structure for pore sizes of 8 × 8 μm or larger. The cells migrating through smaller pore sizes made significantly more turns than those through larger pores. The introduction of additional defined barriers in the microporous structure resulted in dendritic cells making more turns while still being able to follow the chemoattractant concentration gradient.
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Affiliation(s)
- Mark Holm Olsen
- Department of Micro- and Nanotechnology, DTU Nanotech, Technical University of Denmark, Ørsteds Plads 345E, DK-2800 Kgs. Lyngby, Denmark.
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47
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Biased migration of confined neutrophil-like cells in asymmetric hydraulic environments. Proc Natl Acad Sci U S A 2013; 110:21006-11. [PMID: 24324148 DOI: 10.1073/pnas.1317441110] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Cells integrate multiple measurement modalities to navigate their environment. Soluble and substrate-bound chemical gradients and physical cues have all been shown to influence cell orientation and migration. Here we investigate the role of asymmetric hydraulic pressure in directional sensing. Cells confined in microchannels identified and chose a path of lower hydraulic resistance in the absence of chemical cues. In a bifurcating channel with asymmetric hydraulic resistances, this choice was preceded by the elaboration of two leading edges with a faster extension rate along the lower resistance channel. Retraction of the "losing" edge appeared to precipitate a final choice of direction. The pressure differences altering leading edge protrusion rates were small, suggesting weak force generation by leading edges. The response to the physical asymmetry was able to override a dynamically generated chemical cue. Motile cells may use this bias as a result of hydraulic resistance, or "barotaxis," in concert with chemotaxis to navigate complex environments.
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48
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Desai SP, Bhatia SN, Toner M, Irimia D. Mitochondrial localization and the persistent migration of epithelial cancer cells. Biophys J 2013; 104:2077-88. [PMID: 23663851 DOI: 10.1016/j.bpj.2013.03.025] [Citation(s) in RCA: 153] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 02/18/2013] [Accepted: 03/07/2013] [Indexed: 01/02/2023] Open
Abstract
During cancer cell invasion, faster moving cancer cells play a dominant role by invading further and metastasizing earlier. Despite the importance of these outlier cells, the source of heterogeneity in their migratory behavior remains poorly understood. Here, we show that anterior localization of mitochondria, in between the nucleus and the leading edge of migrating epithelial cancer cells, correlates with faster migration velocities and increased directional persistence. The asymmetry of mitochondrial localization along the axis of migration is absent during spontaneous cell migration on two-dimensional surfaces and only occurs in the presence of chemical attractant cues or in conditions of mechanical confinement. Moreover, perturbing the asymmetric distribution of mitochondria within migrating cells by interfering with mitochondrial fusion (opa-1) or fission (drp-1) proteins, significantly reduces the number of cells with anterior localization of mitochondria and significantly decreases the velocity and directional persistence of the fastest moving cells. We also observed similar changes after perturbing the linkage between mitochondria and microtubules by the knockdown of mitochondrial rhoGTPase-1 (miro-1). Taken together, the changes in migration velocity and directional persistence in cells with anterior-localized mitochondria could account for an order of magnitude differences in invasive abilities between cells from otherwise homogenous cell populations.
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Affiliation(s)
- Salil P Desai
- Harvard-MIT Division of Health-Science Technology, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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49
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Wu J, Wu X, Lin F. Recent developments in microfluidics-based chemotaxis studies. LAB ON A CHIP 2013; 13:2484-99. [PMID: 23712326 DOI: 10.1039/c3lc50415h] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Microfluidic devices can better control cellular microenvironments compared to conventional cell migration assays. Over the past few years, microfluidics-based chemotaxis studies showed a rapid growth. New strategies were developed to explore cell migration in manipulated chemical gradients. In addition to expanding the use of microfluidic devices for a broader range of cell types, microfluidic devices were used to study cell migration and chemotaxis in complex environments. Furthermore, high-throughput microfluidic chemotaxis devices and integrated microfluidic chemotaxis systems were developed for medical and commercial applications. In this article, we review recent developments in microfluidics-based chemotaxis studies and discuss the new trends in this field observed over the past few years.
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Affiliation(s)
- Jiandong Wu
- Department of Physics and Astronomy, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
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Optical control demonstrates switch-like PIP3 dynamics underlying the initiation of immune cell migration. Proc Natl Acad Sci U S A 2013; 110:E1575-83. [PMID: 23569254 DOI: 10.1073/pnas.1220755110] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
There is a dearth of approaches to experimentally direct cell migration by continuously varying signal input to a single cell, evoking all possible migratory responses and quantitatively monitoring the cellular and molecular response dynamics. Here we used a visual blue opsin to recruit the endogenous G-protein network that mediates immune cell migration. Specific optical inputs to this optical trigger of signaling helped steer migration in all possible directions with precision. Spectrally selective imaging was used to monitor cell-wide phosphatidylinositol (3,4,5)-triphosphate (PIP3), cytoskeletal, and cellular dynamics. A switch-like PIP3 increase at the cell front and a decrease at the back were identified, underlying the decisive migratory response. Migration was initiated at the rapidly increasing switch stage of PIP3 dynamics. This result explains how a migratory cell filters background fluctuations in the intensity of an extracellular signal but responds by initiating directionally sensitive migration to a persistent signal gradient across the cell. A two-compartment computational model incorporating a localized activator that is antagonistic to a diffusible inhibitor was able to simulate the switch-like PIP3 response. It was also able simulate the slow dissipation of PIP3 on signal termination. The ability to independently apply similar signaling inputs to single cells detected two cell populations with distinct thresholds for migration initiation. Overall the optical approach here can be applied to understand G-protein-coupled receptor network control of other cell behaviors.
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