1
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Haupt S, Gleim N, Ahadova A, Bläker H, Knebel Doeberitz M, Kloor M, Heuveline V. A computational model for investigating the evolution of colonic crypts during Lynch syndrome carcinogenesis. COMPUTATIONAL AND SYSTEMS ONCOLOGY 2021. [DOI: 10.1002/cso2.1020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Saskia Haupt
- Engineering Mathematics and Computing Lab (EMCL) Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University Heidelberg Germany
- Data Mining and Uncertainty Quantification (DMQ) Heidelberg Institute for Theoretical Studies (HITS) Heidelberg Germany
| | - Nils Gleim
- Engineering Mathematics and Computing Lab (EMCL) Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University Heidelberg Germany
| | - Aysel Ahadova
- Department of Applied Tumor Biology (ATB) Institute of Pathology, University Hospital Heidelberg Heidelberg Germany
- Clinical Cooperation Unit Applied Tumor Biology German Cancer Research Center Heidelberg Germany
| | - Hendrik Bläker
- Institute of Pathology University Hospital Leipzig Leipzig Germany
| | - Magnus Knebel Doeberitz
- Department of Applied Tumor Biology (ATB) Institute of Pathology, University Hospital Heidelberg Heidelberg Germany
- Clinical Cooperation Unit Applied Tumor Biology German Cancer Research Center Heidelberg Germany
| | - Matthias Kloor
- Department of Applied Tumor Biology (ATB) Institute of Pathology, University Hospital Heidelberg Heidelberg Germany
- Clinical Cooperation Unit Applied Tumor Biology German Cancer Research Center Heidelberg Germany
| | - Vincent Heuveline
- Engineering Mathematics and Computing Lab (EMCL) Interdisciplinary Center for Scientific Computing (IWR), Heidelberg University Heidelberg Germany
- Data Mining and Uncertainty Quantification (DMQ) Heidelberg Institute for Theoretical Studies (HITS) Heidelberg Germany
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2
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From cell shape to cell fate via the cytoskeleton - Insights from the epidermis. Exp Cell Res 2019; 378:232-237. [PMID: 30872138 DOI: 10.1016/j.yexcr.2019.03.016] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 03/02/2019] [Accepted: 03/08/2019] [Indexed: 12/31/2022]
Abstract
Animal cells exhibit a wide range of shapes that reflect their diverse functions. Cell shape is determined by a balance between internal and external forces and therefore involves the cytoskeleton and its associated adhesion structures. Cell shape dynamics during development and homeostasis are tightly regulated and closely coordinated with cell fate determination. Defects in cell shape are a hallmark of many pathological conditions including cancer and skin diseases. This review highlights the links between cell shape and cell fate in the epidermis, which have been studied for over 40 years both in vitro and in vivo. Briefly discussing seminal experiments showing the strong coupling between keratinocyte cell shape and their fate we primarily focus on recent studies uncovering novel cellular and molecular mechanisms linking epidermal cell shape with cell growth, differentiation, asymmetric division, and delamination.
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3
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Yokouchi M, Kubo A. Maintenance of tight junction barrier integrity in cell turnover and skin diseases. Exp Dermatol 2018; 27:876-883. [DOI: 10.1111/exd.13742] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 06/29/2018] [Accepted: 07/13/2018] [Indexed: 02/01/2023]
Affiliation(s)
- Mariko Yokouchi
- Department of Dermatology; Keio University School of Medicine; Tokyo Japan
- Nerima General Hospital; Tokyo Japan
| | - Akiharu Kubo
- Department of Dermatology; Keio University School of Medicine; Tokyo Japan
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4
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Yokouchi M, Atsugi T, Logtestijn MV, Tanaka RJ, Kajimura M, Suematsu M, Furuse M, Amagai M, Kubo A. Epidermal cell turnover across tight junctions based on Kelvin's tetrakaidecahedron cell shape. eLife 2016; 5:19593. [PMID: 27894419 PMCID: PMC5127639 DOI: 10.7554/elife.19593] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 11/01/2016] [Indexed: 12/17/2022] Open
Abstract
In multicellular organisms, cells adopt various shapes, from flattened sheets of endothelium to dendritic neurons, that allow the cells to function effectively. Here, we elucidated the unique shape of cells in the cornified stratified epithelia of the mammalian epidermis that allows them to achieve homeostasis of the tight junction (TJ) barrier. Using intimate in vivo 3D imaging, we found that the basic shape of TJ-bearing cells is a flattened Kelvin's tetrakaidecahedron (f-TKD), an optimal shape for filling space. In vivo live imaging further elucidated the dynamic replacement of TJs on the edges of f-TKD cells that enables the TJ-bearing cells to translocate across the TJ barrier. We propose a spatiotemporal orchestration model of f-TKD cell turnover, where in the classic context of 'form follows function', cell shape provides a fundamental basis for the barrier homeostasis and physical strength of cornified stratified epithelia. DOI:http://dx.doi.org/10.7554/eLife.19593.001 The skin surface – known as the epidermis – is made up of sheets of cells that are stacked up in layers. One of the roles of the skin is to provide a protective barrier that limits what leaks into or out of the body. A particular layer of the epidermis – referred to as the stratum granulosum – is primarily responsible for forming this barrier. The cells in this layer are sealed together in a zipper-like fashion by structures known as tight junctions. New skin cells are continuously produced in the lowest cell layers of the epidermis, and move upwards to integrate into the stratum granulosum layer to replace old cells (which also move upwards to leave the layer). How stratum granulosum cells are replaced without disrupting the tight junction barrier was not well understood. Yokouchi et al. used a technique called confocal microscopy to examine the stratum granulosum cells in the ears of mice, and found that the shape of these cells forms the basis of the barrier that they form. These cells resemble a flattened version of a shape called Kelvin’s tetrakaidecahedron: a 14-sided solid with six rectangular and eight hexagonal sides. This structure was proposed by Lord Kelvin in 1887 to be the best shape for filling space. Tight junctions are present on the edges of the flattened Kelvin’s tetrakaidecahedron. Further experiments revealed that the tight junctions move from cell to cell in a spatiotemporally-coordinated manner in order to maintain a continuous barrier throughout the stratum granulosum as cells are replaced. A newly formed stratum granulosum cell appears beneath the cell that it will replace. The shape of these cells enables a new barrier of three-way tight junction contacts to form between them and the neighboring cells in the stratum granulosum. After this barrier has formed, the upper cell leaves the stratum granulosum. Future research could address how cells adopt the flattened Kelvin’s tetrakaidecahedron shape, and discover why tight junctions only form in one layer of the epidermis. DOI:http://dx.doi.org/10.7554/eLife.19593.002
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Affiliation(s)
- Mariko Yokouchi
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan.,Nerima General Hospital, Tokyo, Japan
| | - Toru Atsugi
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan.,KOSÉ Corporation, Tokyo, Japan
| | - Mark van Logtestijn
- Department of Bioengineering, Faculty of Engineering, Imperial College London, London, United Kingdom
| | - Reiko J Tanaka
- Department of Bioengineering, Faculty of Engineering, Imperial College London, London, United Kingdom
| | - Mayumi Kajimura
- Department of Biochemistry, Keio University School of Medicine, Tokyo, Japan.,Suematsu Gas Biology Project, Exploratory Research for Advanced Technology, Japan Science and Technology, Tokyo, Japan
| | - Makoto Suematsu
- Department of Biochemistry, Keio University School of Medicine, Tokyo, Japan.,Suematsu Gas Biology Project, Exploratory Research for Advanced Technology, Japan Science and Technology, Tokyo, Japan
| | - Mikio Furuse
- Division of Cell Structure, National Institute for Physiological Sciences, Okazaki, Japan.,Department of Physiological Sciences, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Japan
| | - Masayuki Amagai
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan.,RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Akiharu Kubo
- Department of Dermatology, Keio University School of Medicine, Tokyo, Japan
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5
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Rompolas P, Mesa KR, Kawaguchi K, Park S, Gonzalez D, Brown S, Boucher J, Klein AM, Greco V. Spatiotemporal coordination of stem cell commitment during epidermal homeostasis. Science 2016; 352:1471-4. [PMID: 27229141 PMCID: PMC4958018 DOI: 10.1126/science.aaf7012] [Citation(s) in RCA: 149] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Accepted: 05/18/2016] [Indexed: 12/30/2022]
Abstract
Adult tissues replace lost cells via pools of stem cells. However, the mechanisms of cell self-renewal, commitment, and functional integration into the tissue remain unsolved. Using imaging techniques in live mice, we captured the lifetime of individual cells in the ear and paw epidermis. Our data suggest that epidermal stem cells have equal potential to either divide or directly differentiate. Tracking stem cells over multiple generations reveals that cell behavior is not coordinated between generations. However, sibling cell fate and lifetimes are coupled. We did not observe regulated asymmetric cell divisions. Lastly, we demonstrated that differentiating stem cells integrate into preexisting ordered spatial units of the epidermis. This study elucidates how a tissue is maintained by both temporal and spatial coordination of stem cell behaviors.
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Affiliation(s)
| | - Kailin R. Mesa
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Kyogo Kawaguchi
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Sangbum Park
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - David Gonzalez
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Samara Brown
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Jonathan Boucher
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
| | - Allon M. Klein
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Valentina Greco
- Department of Genetics, Yale School of Medicine, New Haven, CT 06510, USA
- Departments of Dermatology and Cell Biology, Yale Stem Cell Center, Yale Cancer Center, Yale School of Medicine, New Haven, CT 06510, USA
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6
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Wabik A, Jones PH. Switching roles: the functional plasticity of adult tissue stem cells. EMBO J 2015; 34:1164-79. [PMID: 25812989 PMCID: PMC4426478 DOI: 10.15252/embj.201490386] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 01/09/2015] [Accepted: 02/11/2015] [Indexed: 12/15/2022] Open
Abstract
Adult organisms have to adapt to survive, and the same is true for their tissues. Rates and types of cell production must be rapidly and reversibly adjusted to meet tissue demands in response to both local and systemic challenges. Recent work reveals how stem cell (SC) populations meet these requirements by switching between functional states tuned to homoeostasis or regeneration. This plasticity extends to differentiating cells, which are capable of reverting to SCs after injury. The concept of the niche, the micro-environment that sustains and regulates stem cells, is broadening, with a new appreciation of the role of physical factors and hormonal signals. Here, we review different functions of SCs, the cellular mechanisms that underlie them and the signals that bias the fate of SCs as they switch between roles.
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Affiliation(s)
- Agnieszka Wabik
- MRC Cancer Unit, University of Cambridge Hutchison/MRC Research Centre Cambridge Biomedical Campus, Cambridge, UK
| | - Philip H Jones
- MRC Cancer Unit, University of Cambridge Hutchison/MRC Research Centre Cambridge Biomedical Campus, Cambridge, UK Wellcome Trust Sanger Institute, Hinxton, UK
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7
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Honda H, Nagai T. Cell models lead to understanding of multi-cellular morphogenesis consisting of successive self-construction of cells. J Biochem 2014; 157:129-36. [PMID: 25552548 DOI: 10.1093/jb/mvu088] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Morphogenesis of multi-cellular organisms occurs through cell behaviours within a cell aggregate. Cell behaviours have been described using cell models involving equations of motion for cells. Cells in cell models construct shapes of the cell aggregate by themselves. Here, a history of cell models, the cell centre model and the vertex cell model, which we have constructed, are described. Furthermore, the application of these cell models is explained in detail. These cell models have been applied to transformation of cell aggregates to become spherical, formation of mammalian blastocysts and cell intercalation in elongating tissues. These are all elemental processes of morphogenesis and take place in succession during the whole developmental process. A chain of successive elemental processes leads to morphogenesis. Finally, we highlight that cell models are indispensable to understand the process whereby genes direct biological shapes.
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Affiliation(s)
- Hisao Honda
- Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; RIKEN Center for Developmental Biology, Kobe 650-0047, Japan; and Research Institute, Kyushu Kyoritsu University, Kitakyushu, Fukuoka 807-8585, Japan Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; RIKEN Center for Developmental Biology, Kobe 650-0047, Japan; and Research Institute, Kyushu Kyoritsu University, Kitakyushu, Fukuoka 807-8585, Japan
| | - Tatsuzo Nagai
- Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650-0017, Japan; RIKEN Center for Developmental Biology, Kobe 650-0047, Japan; and Research Institute, Kyushu Kyoritsu University, Kitakyushu, Fukuoka 807-8585, Japan
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8
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Mengel Pers B, Krishna S, Chakraborty S, Pigolotti S, Sekara V, Semsey S, Jensen MH. Effects of growth and mutation on pattern formation in tissues. PLoS One 2012; 7:e48772. [PMID: 23144963 PMCID: PMC3492435 DOI: 10.1371/journal.pone.0048772] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 10/05/2012] [Indexed: 12/21/2022] Open
Abstract
In many developing tissues, neighboring cells enter different developmental pathways, resulting in a fine-grained pattern of different cell states. The most common mechanism that generates such patterns is lateral inhibition, for example through Delta-Notch coupling. In this work, we simulate growth of tissues consisting of a hexagonal arrangement of cells laterally inhibiting their neighbors. We find that tissue growth by cell division and cell migration tends to produce ordered patterns, whereas lateral growth leads to disordered, patchy patterns. Ordered patterns are very robust to mutations (gene silencing or activation) in single cells. In contrast, mutation in a cell of a disordered tissue can produce a larger and more widespread perturbation of the pattern. In tissues where ordered and disordered patches coexist, the perturbations spread mostly at boundaries between patches. If cell division occurs on time scales faster than the degradation time, disordered patches will appear. Our work suggests that careful experimental characterization of the disorder in tissues could pinpoint where and how the tissue is susceptible to large-scale damage even from single cell mutations.
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Affiliation(s)
- Benedicte Mengel Pers
- Center for Models of Life, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Sandeep Krishna
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India
| | - Sagar Chakraborty
- Center for Models of Life, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Simone Pigolotti
- Center for Models of Life, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Vedran Sekara
- Center for Models of Life, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Szabolcs Semsey
- Center for Models of Life, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
| | - Mogens H. Jensen
- Center for Models of Life, Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark
- * E-mail:
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9
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Act your age: tuning cell behavior to tissue requirements in interfollicular epidermis. Semin Cell Dev Biol 2012; 23:884-9. [PMID: 22981943 DOI: 10.1016/j.semcdb.2012.08.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Revised: 08/30/2012] [Accepted: 08/31/2012] [Indexed: 11/23/2022]
Abstract
In all tissues the balance of cell proliferation and differentiation needs to be tuned to match the varying requirements of embryonic development and adult life. This is well illustrated by the interfollicular epidermis (IFE), which undergoes expansion and remodeling in utero, significant post natal growth and is then maintained in homeostasis. In addition to sustaining a high daily turnover of cells, the epidermis is able to re-populate areas of tissue damage due to common environmental stresses such as wounding. Here recent insights into proliferating cell behavior in IFE and how this changes through development and into adulthood are discussed.
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10
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Chakraborty S, Jensen MH, Krishna S, Mengel Pers B, Pigolotti S, Sekara V, Semsey S. Limit-cycle oscillations and stable patterns in repressor lattices. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 86:031905. [PMID: 23030942 DOI: 10.1103/physreve.86.031905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 07/06/2012] [Indexed: 06/01/2023]
Abstract
As a model for cell-to-cell communication in biological tissues, we construct repressor lattices by repeating a regulatory three-node motif on a hexagonal structure. Local interactions can be unidirectional, where a node either represses or activates a neighbor that does not communicate backwards. Alternatively, they can be bidirectional where two neighboring nodes communicate with each other. In the unidirectional case, we perform stability analyses for the transitions from stationary to oscillating states in lattices with different regulatory units. In the bidirectional case, we investigate transitions from oscillating states to ordered patterns generated by local switches. Finally, we show how such stable patterns in two-dimensional lattices can be generalized to three-dimensional systems.
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Affiliation(s)
- Sagar Chakraborty
- NBIA, Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, 2100 Copenhagen Ø, Denmark.
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11
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Roshan A, Jones PH. Chronic low dose UV exposure and p53 mutation: tilting the odds in early epidermal preneoplasia? Int J Radiat Biol 2012; 88:682-7. [PMID: 22671441 DOI: 10.3109/09553002.2012.699697] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
PURPOSE This review addresses how mutation of the TP53 gene (p53) and ultraviolet light alter the behavior of normal progenitor cells in early epidermal preneoplasia. CONCLUSIONS Cancer is thought to evolve from single mutant cells, which expand into clones and ultimately into tumors. While the mutations in malignant lesions have been studied intensively, less is known about the earliest stages of preneoplasia, and how environmental factors may contribute to drive expansion of mutant cell clones. Here we review the evidence that ultraviolet radiation not only creates new mutations but drives the exponential growth of the numerous p53 mutant clones found in chronically exposed epidermis. Published data is reconciled with a new paradigm of epidermal homeostasis which gives insights into the behavior of mutant cells. We also consider the reasons why so few mutant cells progress into tumors and discuss the implications of these findings for cancer prevention.
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Affiliation(s)
- Amit Roshan
- Department of Plastic Surgery, Addenbrooke's Hospital, Cambridge, UK
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12
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Hočevar A, Ziherl P. Periodic three-dimensional assemblies of polyhedral lipid vesicles. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:041917. [PMID: 21599210 DOI: 10.1103/physreve.83.041917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2010] [Indexed: 05/30/2023]
Abstract
We theoretically study the structure of periodic bulk assemblies of identical lipid vesicles. In our model, each vesicle is represented as a convex polyhedron with flat faces, rounded edges, and rounded vertices. Each vesicle carries an elastic and an adhesion energy and in the limit of strong adhesion, the minimal-energy shape of cells minimizes the weighted total edge length. We calculate exactly the shape of the rounded edge and show that it can be well described by a cylindrical surface. By comparing several candidate space-filling polyhedra, we find that the oblate shapes are preferred over prolate shapes for all volume-to-surface ratios. We also study periodic assemblies of vesicles whose adhesion strength on lateral faces is different from that on basal or apical faces. The anisotropy needed to stabilize prolate shapes is determined and it is shown that, at any volume-to-surface ratio, the transition between oblate and prolate shapes is very sharp. The geometry of the model vesicle assemblies reproduces the shapes of cells in certain simple animal tissues.
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Affiliation(s)
- A Hočevar
- Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
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13
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Doupé DP, Klein AM, Simons BD, Jones PH. The ordered architecture of murine ear epidermis is maintained by progenitor cells with random fate. Dev Cell 2010; 18:317-23. [PMID: 20159601 DOI: 10.1016/j.devcel.2009.12.016] [Citation(s) in RCA: 179] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2009] [Revised: 11/27/2009] [Accepted: 12/16/2009] [Indexed: 12/31/2022]
Abstract
Typical murine epidermis has a patterned structure, seen clearly in ear skin, with regular columns of differentiated cells overlying the proliferative basal layer. It has been proposed that each column is a clonal epidermal proliferative unit maintained by a central stem cell and its transit amplifying cell progeny. An alternative hypothesis is that proliferating basal cells have random fate, the probability of generating cycling or differentiated cells being balanced so homeostasis is achieved. The stochastic model seems irreconcilable with an ordered tissue. Here we use lineage tracing to reveal that basal cells generate clones with highly irregular shapes that contribute progeny to multiple columns. Basal cell fate and cell cycle time is random. Cell columns form due to the properties of postmitotic cells. We conclude that the ordered architecture of the epidermis is maintained by a stochastic progenitor cell population, providing a simple and robust mechanism of homeostasis.
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Affiliation(s)
- David P Doupé
- MRC Cancer Cell Unit, Hutchison-MRC Research Centre, Cambridge CB2 0XZ, UK
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14
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Emily M, François O. A statistical approach to estimating the strength of cell-cell interactions under the differential adhesion hypothesis. Theor Biol Med Model 2007; 4:37. [PMID: 17877791 PMCID: PMC2213651 DOI: 10.1186/1742-4682-4-37] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Accepted: 09/18/2007] [Indexed: 11/27/2022] Open
Abstract
Background The Differential Adhesion Hypothesis (DAH) is a theory of the organization of cells within a tissue which has been validated by several biological experiments and tested against several alternative computational models. Results In this study, a statistical approach was developed for the estimation of the strength of adhesion, incorporating earlier discrete lattice models into a continuous marked point process framework. This framework allows to describe an ergodic Markov Chain Monte Carlo algorithm that can simulate the model and reproduce empirical biological patterns. The estimation procedure, based on a pseudo-likelihood approximation, is validated with simulations, and a brief application to medulloblastoma stained by beta-catenin markers is given. Conclusion Our model includes the strength of cell-cell adhesion as a statistical parameter. The estimation procedure for this parameter is consistent with experimental data and would be useful for high-throughput cancer studies.
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Affiliation(s)
- Mathieu Emily
- TIMC-TIMB, Université Joseph Fourier, INP Grenoble, Faculty of Medicine, 38706 La Tronche cedex, France
- Bioinformatics Research Center (BiRC), University of Aarhus, Hoegh-Guldbergs Gade 10, 8000 Aarhus C, Denmark
| | - Olivier François
- TIMC-TIMB, Université Joseph Fourier, INP Grenoble, Faculty of Medicine, 38706 La Tronche cedex, France
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15
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Silver L, Qiang L, Loudon R, Gallo G. Bidirectional inhibitory interactions between the embryonic chicken metanephros and lumbosacral nerves in vitro. Dev Dyn 2005; 231:190-8. [PMID: 15305299 DOI: 10.1002/dvdy.20111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
During chicken embryonic development the metanephros forms from the uretic duct at embryonic day (E) 7. As the metanephric tissue develops between E7 and E10, it comes into close apposition with lumbosacral nerves. Coculturing of metanephric and nerve explants demonstrated that the Schwann cells of the sciatic nerve inhibit the migration of metanephric cells in a contact-dependent manner. Conversely, metanephric cells inhibit dorsal root ganglion axon extension in a contact-dependent manner. However, metanephric cells are not inhibited by contact with growth cones or axons. Dorsal root ganglion growth cones become sensitive to the inhibitory signals on the surfaces of metanephric cells around E8, a time when the metanephros is expanding into the territory occupied by nerves in vivo. These observations demonstrate inhibitory bidirectional tissue-tissue interactions in vitro and provide a novel model system for the study of contact-based guidance of both neuronal and non-neuronal cell migration.
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Affiliation(s)
- Lee Silver
- Drexel College of Medicine, Department of Neurobiology and Anatomy, Philadelphia, Pennsylvania, USA
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16
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Honda H, Tanemura M, Nagai T. A three-dimensional vertex dynamics cell model of space-filling polyhedra simulating cell behavior in a cell aggregate. J Theor Biol 2004; 226:439-53. [PMID: 14759650 DOI: 10.1016/j.jtbi.2003.10.001] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2003] [Revised: 10/05/2003] [Accepted: 10/06/2003] [Indexed: 11/30/2022]
Abstract
We developed a three-dimensional (3D) cell model of a multicellular aggregate consisting of several polyhedral cells to investigate the deformation and rearrangement of cells under the influence of external forces. The polyhedral cells fill the space in the aggregate without gaps or overlaps, consist of contracting interfaces and maintain their volumes. The interfaces and volumes were expressed by 3D vertex coordinates. Vertex movements obey equations of motion that rearrange the cells to minimize total free energy, and undergo an elementary process that exchanges vertex pair connections when vertices approach each other. The total free energy includes the interface energy of cells and the compression or expansion energy of cells. Computer simulations provided the following results: An aggregate of cells becomes spherical to minimize individual cell surface areas; Polygonal interfaces of cells remain flat; Cells within the 3D cell aggregate can move and rearrange despite the absence of free space. We examined cell rearrangement to elucidate the viscoelastic properties of the aggregate, e.g. when an external force flattens a cell aggregate (e.g. under centrifugation) its component cells quickly flatten. Under a continuous external force, the cells slowly rearrange to recover their original shape although the cell aggregate remains flat. The deformation and rearrangement of individual cells is a two-step process with a time lag. Our results showed that morphological and viscoelastic properties of the cell aggregate with long relaxation time are based on component cells where minimization of interfacial energy of cells provides a motive force for cell movement.
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Affiliation(s)
- Hisao Honda
- Institute of Statistical Mathematics, Minami-Azabu 4-6-7, Minato-ku, Tokyo 106-8569, Japan.
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17
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Dubertret B, Rivier N. Geometrical models of the renewal of the epidermis. COMPTES RENDUS DE L'ACADEMIE DES SCIENCES. SERIE III, SCIENCES DE LA VIE 2000; 323:49-56. [PMID: 10742910 DOI: 10.1016/s0764-4469(00)00106-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We give a review of the different models developed recently that describe the renewal of the epidermis. These models, based on concepts borrowed from statistical mechanics, geometry and topology, shed new light on the understanding of the organization and the dynamics of the system. We discuss in detail a topological model of the dynamics of the inner-most layer of the epidermis: the basal layer.
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Affiliation(s)
- B Dubertret
- Center for Studies in Physics and Biology, Rockefeller University, New York, NY 10021, USA.
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Iizuka H, Honda H, Ishida-Yamamoto A. Epidermal remodeling in psoriasis (II): a quantitative analysis of the epidermal architecture. J Invest Dermatol 1997; 109:806-10. [PMID: 9406825 DOI: 10.1111/1523-1747.ep12341002] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Hyperproliferative psoriatic epidermis was quantitatively analyzed using a geometric model of viable epidermis. Our model was based on hexagonally arranged cylindrical papillae, which allowed the determination of the total volume of the viable epidermis and the total area of the interface with the proliferative compartment based on several parameters, such as papillary height, papillary width, and distance between neighboring papillae. The analysis assumed that the total number of viable epidermal cells paralleled the proliferative compartment in a steady state of cell flow, so a quantitative relation could be made between both volume and interface of the viable epidermis. Multiple parameters of the psoriatic epidermal architecture were measured, and variations within psoriasis were predicted by the model. The results predicted were remarkably close to the observed values. The geometric model also indicated that psoriatic epidermis could be subdivided into two distinct types, with and without a granular layer; the latter having a shorter turnover time. This is consistent with the notion that the typical psoriatic epidermis (without the granular layer) represents the expanding hyperproliferative phase, whereas the psoriatic epidermis with a granular layer represents stationary or resolving states. The model of hexagonally arranged cylindrical papillae suggested that the architecture of the psoriatic epidermis is constructed by a simple mechanism, whereby the psoriatic angulated rete-papilla pattern was produced by a two-dimensional increase in the proliferative compartment and a three-dimensional increase in the total volume of the viable epidermis.
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Affiliation(s)
- H Iizuka
- Department of Dermatology, Asahikawa Medical College, Japan
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