1
|
Geng S, Wu Y, Li L. Immune Homeostasis Maintenance Through Advanced Immune Therapeutics to Target Atherosclerosis. Methods Mol Biol 2024; 2782:25-37. [PMID: 38622390 DOI: 10.1007/978-1-0716-3754-8_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
Atherosclerosis remains the leading cause of coronary heart disease (CHD) with enormous health and societal tolls. Traditional drug development approaches have been focused on small molecule-based compounds that aim to lower plasma lipids and reduce systemic inflammation, two primary causes of atherosclerosis. However, despite the widely available lipid-lowering and anti-inflammatory small compounds and biologic agents, CHD prevalence still remains high. Based on recent advances revealing disrupted immune homeostasis during atherosclerosis pathogenesis, novel strategies aimed at rejuvenating immune homeostasis with engineered immune leukocytes are being developed. This chapter aims to assess basic and translational efforts on these emerging strategies for the effective development of atherosclerosis treatment, as well as key challenges in this important translational field.
Collapse
Affiliation(s)
- Shuo Geng
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
| | - Yajun Wu
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA
| | - Liwu Li
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA.
| |
Collapse
|
2
|
Tan F, Xuan Y, Long L, Yu Y, Zhang C, Liang P, Wang Y, Chen M, Wen J, Chen G. Single-cell analysis of human prepuce reveals dynamic changes in gene regulation and cellular communications. BMC Genomics 2023; 24:514. [PMID: 37658288 PMCID: PMC10474653 DOI: 10.1186/s12864-023-09615-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 08/22/2023] [Indexed: 09/03/2023] Open
Abstract
BACKGROUND The cellular and molecular dynamics of human prepuce are crucial for understanding its biological and physiological functions, as well as the prevention of related genital diseases. However, the cellular compositions and heterogeneity of human prepuce at single-cell resolution are still largely unknown. Here we systematically dissected the prepuce of children and adults based on the single-cell RNA-seq data of 90,770 qualified cells. RESULTS We identified 15 prepuce cell subtypes, including fibroblast, smooth muscle cells, T/natural killer cells, macrophages, vascular endothelial cells, and dendritic cells. The proportions of these cell types varied among different individuals as well as between children and adults. Moreover, we detected cell-type-specific gene regulatory networks (GRNs), which could contribute to the unique functions of related cell types. The GRNs were also highly dynamic between the prepuce cells of children and adults. Our cell-cell communication network analysis among different cell types revealed a set of child-specific (e.g., CD96, EPO, IFN-1, and WNT signaling pathways) and adult-specific (e.g., BMP10, NEGR, ncWNT, and NPR1 signaling pathways) signaling pathways. The variations of GRNs and cellular communications could be closely associated with prepuce development in children and prepuce maintenance in adults. CONCLUSIONS Collectively, we systematically analyzed the cellular variations and molecular changes of the human prepuce at single-cell resolution. Our results gained insights into the heterogeneity of prepuce cells and shed light on the underlying molecular mechanisms of prepuce development and maintenance.
Collapse
Affiliation(s)
- Fei Tan
- School of Medicine, Shanghai Skin Disease Hospital, Tongji University, Shanghai, 200443, China.
- Shanghai Skin Disease Clinical College, The Fifth Clinical Medical College, Anhui Medical University, Shanghai Skin Disease Hospital, Shanghai, 200443, China.
| | - Yuan Xuan
- Shanghai Skin Disease Clinical College, The Fifth Clinical Medical College, Anhui Medical University, Shanghai Skin Disease Hospital, Shanghai, 200443, China
| | - Lan Long
- Longgang District Maternity & Child Healthcare Hospital of Shenzhen City, Shenzhen, 518172, China
| | - Yang Yu
- Department of Urology, Shanghai Tenth People's Hospital, Tongji University School of Medicine, Shanghai, 200072, China
| | - Chunhua Zhang
- Department of Dermatology, Shanghai Baoshan Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai, 201999, China
| | - Pengchen Liang
- School of Microelectronics, Shanghai University, Shanghai, 201800, China
| | - Yaoqun Wang
- Shanghai Skin Disease Clinical College, The Fifth Clinical Medical College, Anhui Medical University, Shanghai Skin Disease Hospital, Shanghai, 200443, China
| | - Meiyu Chen
- Shanghai Skin Disease Clinical College, The Fifth Clinical Medical College, Anhui Medical University, Shanghai Skin Disease Hospital, Shanghai, 200443, China
| | - Jiling Wen
- Department of Urology, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China.
| | - Geng Chen
- School of Medicine, Shanghai Skin Disease Hospital, Tongji University, Shanghai, 200443, China.
- Center for Bioinformatics and Computational Biology, School of Life Sciences, East China Normal University, Shanghai, 200241, China.
| |
Collapse
|
3
|
Singh SN, Malik MZ, Singh RKB. Molecular crosstalk: Notch can manipulate Hes1 and miR-9 behavior. J Theor Biol 2020; 504:110404. [PMID: 32717196 DOI: 10.1016/j.jtbi.2020.110404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 03/05/2020] [Accepted: 07/08/2020] [Indexed: 01/18/2023]
Abstract
We propose a Hes1-Notch-miR-9 regulatory network and studied the regulating mechanism of miR-9 and Hes1 dynamics driven by Notch. Change in Notch concentration, which serves as a stress signal, can trigger the dynamics of Hes1 and miR-9 at five different states, namely, sTable (2), sustain (1) and mixed (2) states those may correspond to different cellular states. Further, this Notch stress signal introduce time reversal oscillation, which behaves as backward wave, after a certain threshold value of the stress signal and defends the system from moving to apoptosis. We also observe heterogeneous patterns of Hes1, miR-9 and other molecular species in various two dimensional parameter spaces and found that the variability in the patterns is triggered by Hill coefficient and Hes1 stress signal. The phase or bifurcation diagram in time period of oscillation (TN) driven by Notch signal provides all five states, predicts minimum threshold value TNc beyond which tendency to build up backward wave starts and TNc serves as bifurcation point of the system.
Collapse
Affiliation(s)
- Shakti Nath Singh
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Md Zubbair Malik
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| | - R K Brojen Singh
- School of Computational and Integrative Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
| |
Collapse
|
4
|
Gheorghiu M, Stănică L, Ghinia Tegla MG, Polonschii C, Bratu D, Popescu O, Badea T, Gheorghiu E. Cellular sensing platform with enhanced sensitivity based on optogenetic modulation of cell homeostasis. Biosens Bioelectron 2020; 154:112003. [PMID: 32056953 PMCID: PMC7685521 DOI: 10.1016/j.bios.2019.112003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 12/26/2019] [Accepted: 12/28/2019] [Indexed: 12/29/2022]
Abstract
We demonstrate a new biosensing concept with impact on the development of rapid, point of need cell based sensing with boosted sensitivity and wide relevance for bioanalysis. It involves optogenetic stimulation of cells stably transfected to express light sensitive protein channels for optical control of membrane potential and of ion homeostasis. Time-lapse impedance measurements are used to reveal cell dynamics changes encompassing cellular responses to bioactive stimuli and optically induced homeostasis disturbances. We prove that light driven perturbations of cell membrane potential induce homeostatic reactions and modulate transduction mechanisms that amplify cellular response to bioactive compounds. This allows cell based biosensors to respond more rapidly and sensitively to low concentrations of bioactive/toxic analytes: statistically relevant impedance changes are recorded in less than 30 min, in comparison with >8 h in the best alternative reported tests for the same low concentration (e.g. a concentration of 25 μM CdCl2, lower than the threshold concentration in classical cellular sensors). Comparative analysis of model bioactive/toxic compounds (ouabain and CdCl2) demonstrates that cellular reactivity can be boosted by light driven perturbations of cellular homeostasis and that this biosensing concept is able to discriminate analytes with different modes of action (i.e. CdCl2 toxicity versus ion pump inhibition by ouabain), a significant advance against state of the art cell based sensors.
Collapse
Affiliation(s)
- Mihaela Gheorghiu
- International Centre of Biodynamics, Intr. Portocalelor 1 B, 060101, Bucharest, Romania; Faculty of Biology, University of Bucharest, 91-95 Splaiul Independentei, Bucharest, 050095, Romania.
| | - Luciana Stănică
- International Centre of Biodynamics, Intr. Portocalelor 1 B, 060101, Bucharest, Romania; Faculty of Biology, University of Bucharest, 91-95 Splaiul Independentei, Bucharest, 050095, Romania
| | - Miruna G Ghinia Tegla
- Institute for Interdisciplinary Research in Bio-Nano-Sciences, Molecular Biology Center, Babes-Bolyai-University, 400084, Cluj-Napoca, Romania; Retinal Circuit Development & Genetics Unit N-NRL/NEI/NIH 6 Center Drive Bethesda, 20892, Maryland, United States
| | - Cristina Polonschii
- International Centre of Biodynamics, Intr. Portocalelor 1 B, 060101, Bucharest, Romania.
| | - Dumitru Bratu
- International Centre of Biodynamics, Intr. Portocalelor 1 B, 060101, Bucharest, Romania.
| | - Octavian Popescu
- Institute for Interdisciplinary Research in Bio-Nano-Sciences, Molecular Biology Center, Babes-Bolyai-University, 400084, Cluj-Napoca, Romania; Institute of Biology, Romanian Academy, 296 Splaiul Independentei, 060031, Bucharest, Romania
| | - Tudor Badea
- Retinal Circuit Development & Genetics Unit N-NRL/NEI/NIH 6 Center Drive Bethesda, 20892, Maryland, United States.
| | - Eugen Gheorghiu
- International Centre of Biodynamics, Intr. Portocalelor 1 B, 060101, Bucharest, Romania; Faculty of Biology, University of Bucharest, 91-95 Splaiul Independentei, Bucharest, 050095, Romania.
| |
Collapse
|
5
|
Li J, Wilson MN, Bower AJ, Marjanovic M, Chaney EJ, Barkalifa R, Boppart SA. Video-rate multimodal multiphoton imaging and three-dimensional characterization of cellular dynamics in wounded skin. J Innov Opt Health Sci 2020; 13:2050007. [PMID: 33584862 PMCID: PMC7880242 DOI: 10.1142/s1793545820500078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
To date, numerous studies have been performed to elucidate the complex cellular dynamics in skin diseases, but few have attempted to characterize these cellular events under conditions similar to the native environment. To address this challenge, a three-dimensional (3D) multimodal analysis platform was developed for characterizing in vivo cellular dynamics in skin, which was then utilized to process in vivo wound healing data to demonstrate its applicability. Special attention is focused on in vivo biological parameters that are difficult to study with ex vivo analysis, including 3D cell tracking and techniques to connect biological information obtained from different imaging modalities. These results here open new possibilities for evaluating 3D cellular dynamics in vivo, and can potentially provide new tools for characterizing the skin microenvironment and pathologies in the future.
Collapse
Affiliation(s)
- Joanne Li
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
| | - Madison N. Wilson
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign Urbana, IL, U.S.A
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
| | - Andrew J. Bower
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign Urbana, IL, U.S.A
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
| | - Marina Marjanovic
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
| | - Eric J. Chaney
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
| | - Ronit Barkalifa
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
| | - Stephen A. Boppart
- Department of Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
- Department of Electrical and Computer Engineering, University of Illinois at Urbana-Champaign Urbana, IL, U.S.A
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
- Carle Illinois College of Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, U.S.A
| |
Collapse
|
6
|
Abstract
The Drosophila ovary represents a key in vivo model used to study germline stem cell (GSC) maintenance and stem cell daughter differentiation because these cells and their somatic cell neighbors can be identified at single-cell resolution within their native environment. Here we describe a fluorescent-based technique for the acquisition of 4D datasets of the Drosophila ovariole for periods that can exceed 12 consecutive hours. Live-cell imaging facilitates the investigation of molecular and cellular dynamics that were not previously possible using still images.
Collapse
Affiliation(s)
- Nevine A Shalaby
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
- Institute for Biology, Freie Universität Berlin, 14195, Berlin, Germany.
| | - Michael Buszczak
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
| |
Collapse
|
7
|
Mashaghi A, Marmalidou A, Tehrani M, Grace PM, Pothoulakis C, Dana R. Neuropeptide substance P and the immune response. Cell Mol Life Sci 2016; 73:4249-4264. [PMID: 27314883 PMCID: PMC5056132 DOI: 10.1007/s00018-016-2293-z] [Citation(s) in RCA: 275] [Impact Index Per Article: 34.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 05/25/2016] [Accepted: 06/09/2016] [Indexed: 02/07/2023]
Abstract
Substance P is a peptide mainly secreted by neurons and is involved in many biological processes, including nociception and inflammation. Animal models have provided insights into the biology of this peptide and offered compelling evidence for the importance of substance P in cell-to-cell communication by either paracrine or endocrine signaling. Substance P mediates interactions between neurons and immune cells, with nerve-derived substance P modulating immune cell proliferation rates and cytokine production. Intriguingly, some immune cells have also been found to secrete substance P, which hints at an integral role of substance P in the immune response. These communications play important functional roles in immunity including mobilization, proliferation and modulation of the activity of immune cells. This review summarizes current knowledge of substance P and its receptors, as well as its physiological and pathological roles. We focus on recent developments in the immunobiology of substance P and discuss the clinical implications of its ability to modulate the immune response.
Collapse
Affiliation(s)
- Alireza Mashaghi
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114 USA
| | - Anna Marmalidou
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114 USA
| | - Mohsen Tehrani
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114 USA
| | - Peter M. Grace
- Department of Psychology and Neuroscience, Center for Neuroscience, University of Colorado, Boulder, CO 80309 USA
| | - Charalabos Pothoulakis
- Division of Digestive Diseases, David Geffen School of Medicine, Inflammatory Bowel Disease Center, University of California, Los Angeles, Los Angeles, CA USA
| | - Reza Dana
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114 USA
| |
Collapse
|
8
|
Abstract
The intestinal epithelium is the fastest renewing tissue in mammals and has a large flexibility to adapt to different types of damage. Lgr5+ crypt base columnar (CBC) cells act as stem cells during homeostasis and are essential during regeneration. Upon perturbation, the activity of CBCs is dynamically regulated to maintain homeostasis and multiple dedicated progenitor cell populations can reverse to the stem cell state upon damage, adding another layer of compensatory mechanisms to facilitate regeneration. Here, we review our current understanding of how intestinal stem and progenitor cells contribute to homeostasis and regeneration, and the different signaling pathways that regulate their behavior. Nutritional state and inflammation have been recently identified as upstream regulators of stem cell activity in the mammalian intestine, and we explore how these systemic signals can influence homeostasis and regeneration.
Collapse
Affiliation(s)
- Joep Beumer
- Hubrecht Institute for Developmental Biology and Stem Cell Research, 3584 CT, Utrecht, The Netherlands
- Cancer Genomics Netherlands, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Hans Clevers
- Hubrecht Institute for Developmental Biology and Stem Cell Research, 3584 CT, Utrecht, The Netherlands
- Cancer Genomics Netherlands, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| |
Collapse
|
9
|
Abstract
Fluorescent 'intravital' imaging is a new research technique by which the interior of living tissues and organs (in living bodies, if possible) can be observed, revealing the kinetics of cell and molecular processes in real time. Recent technological innovations in optical equipment and fluorescence imaging techniques have enabled a variety of cellular phenomena in different tissues and organs to be characterized under completely native conditions. This shift from static to dynamic biology constitutes the beginning of a new era in biomedical sciences.
Collapse
|
10
|
Ray HJ, Niswander LA. Dynamic behaviors of the non-neural ectoderm during mammalian cranial neural tube closure. Dev Biol 2016; 416:279-85. [PMID: 27343896 DOI: 10.1016/j.ydbio.2016.06.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 05/26/2016] [Accepted: 06/19/2016] [Indexed: 11/27/2022]
Abstract
The embryonic brain and spinal cord initially form through the process of neural tube closure (NTC). NTC is thought to be highly similar between rodents and humans, and studies of mouse genetic mutants have greatly increased our understanding of the molecular basis of NTC with relevance for human neural tube defects. In addition, studies using amphibian and chick embryos have shed light into the cellular and tissue dynamics underlying NTC. However, the dynamics of mammalian NTC has been difficult to study due to in utero development until recently when advances in mouse embryo ex vivo culture techniques along with confocal microscopy have allowed for imaging of mouse NTC in real time. Here, we have performed live imaging of mouse embryos with a particular focus on the non-neural ectoderm (NNE). Previous studies in multiple model systems have found that the NNE is important for proper NTC, but little is known about the behavior of these cells during mammalian NTC. Here we utilized a NNE-specific genetic labeling system to assess NNE dynamics during murine NTC and identified different NNE cell behaviors as the cranial region undergoes NTC. These results bring valuable new insight into regional differences in cellular behavior during NTC that may be driven by different molecular regulators and which may underlie the various positional disruptions of NTC observed in humans with neural tube defects.
Collapse
Affiliation(s)
- Heather J Ray
- Department of Pediatrics, Cell Biology Stem Cells and Development Graduate Program, University of Colorado Anschutz Medical Campus and Children's Hospital Colorado, Aurora, CO 80045, USA
| | - Lee A Niswander
- Department of Pediatrics, Cell Biology Stem Cells and Development Graduate Program, University of Colorado Anschutz Medical Campus and Children's Hospital Colorado, Aurora, CO 80045, USA.
| |
Collapse
|
11
|
Magno R, Grieneisen VA, Marée AF. The biophysical nature of cells: potential cell behaviours revealed by analytical and computational studies of cell surface mechanics. BMC Biophys 2015; 8:8. [PMID: 26023328 DOI: 10.1186/s13628-015-0022-x] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 04/24/2015] [Indexed: 11/10/2022]
Abstract
BACKGROUND The biophysical characteristics of cells determine their shape in isolation and when packed within tissues. Cells can form regular or irregular epithelial structures, round up and form clusters, or deform and attach to substrates. The acquired shape of cells and tissues is a consequence of (i) internal cytoskeletal processes, such as actin polymerisation and cortical myosin contraction, (ii) adhesion molecules within the cell membrane that interact with substrates and neighbouring cells, and (iii) processes that regulate cell volume. Although these processes seem relatively simple, when combined they unleash a rich variety of cellular behaviour that is not readily understandable outside a theoretical framework. METHODS We perform a mathematical analysis of a commonly used class of model formalisms that describe cell surface mechanics using an energy-based approach. Predictions are then confirmed through comparison with the computational outcomes of a Vertex model and 2D and 3D simulations of the Cellular Potts model. RESULTS The analytical study reveals the complete possible spectrum of single cell behaviour and tissue packing in both 2D and 3D, by taking the typical core elements of cell surface mechanics into account: adhesion, cortical tension and volume conservation. We show that from an energy-based description, forces and tensions can be derived, as well as the prediction of cell behaviour and tissue packing, providing an intuitive and biologically relevant mapping between modelling parameters and experiments. CONCLUSIONS The quantitative cellular behaviours and biological insights agree between the analytical study and the diverse computational model formalisms, including the Cellular Potts model. This illustrates the generality of energy-based approaches for cell surface mechanics and highlights how meaningful and quantitative comparisons between models can be established. Moreover, the mathematical analysis reveals direct links between known biophysical properties and specific parameter settings within the Cellular Potts model.
Collapse
|
12
|
Abstract
Cells proliferate by division into similar daughter cells, a process that lies at the heart of cell biology. Extensive research on cell division has led to the identification of the many components and control elements of the molecular machinery underlying cellular division. Here we provide a brief review of prokaryotic and eukaryotic cell division and emphasize how new approaches such as systems and synthetic biology can provide valuable new insight.
Collapse
Affiliation(s)
- Alireza Mashaghi
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| | - Cees Dekker
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
| |
Collapse
|
13
|
Abstract
The directional migration of primordial germ cells (PGCs) to the site of gonad formation is an advantageous model system to study cell motility. The embryonic development of PGCs has been investigated in different animal species, including mice, zebrafish, Xenopus and Drosophila. In this study we focus on the physical properties of Xenopus laevis PGCs during their transition from the passive to the active migratory state. Pre-migratory PGCs from Xenopus laevis embryos at developmental stages 17–19 to be compared with migratory PGCs from stages 28–30 were isolated and characterized in respect to motility and adhesive properties. Using single-cell force spectroscopy, we observed a decline in adhesiveness of PGCs upon reaching the migratory state, as defined by decreased attachment to extracellular matrix components like fibronectin, and a reduced adhesion to somatic endodermal cells. Data obtained from qPCR analysis with isolated PGCs reveal that down-regulation of E-cadherin might contribute to this weakening of cell-cell adhesion. Interestingly, however, using an in vitro migration assay, we found that movement of X. laevis PGCs can also occur independently of specific interactions with their neighboring cells. The reduction of cellular adhesion during PGC development is accompanied by enhanced cellular motility, as reflected in increased formation of bleb-like protrusions and inferred from electric cell-substrate impedance sensing (ECIS) as well as time-lapse image analysis. Temporal alterations in cell shape, including contraction and expansion of the cellular body, reveal a higher degree of cellular dynamics for the migratory PGCs in vitro.
Collapse
Affiliation(s)
- Aliaksandr Dzementsei
- Department of Developmental Biochemistry, Göttingen Center for Molecular Biosciences, Georg-August-University, Justus-von-Liebig-Weg 11, 37077 Göttingen, Germany
| | | | | | | |
Collapse
|
14
|
Abstract
Embryogenesis is a dynamic process with an intrinsic variability whose understanding requires the integration of molecular, genetic, and cellular dynamics. Biological circuits function over time at the level of single cells and require a precise analysis of the topology, temporality, and probability of events. Integrative developmental biology is currently looking for the appropriate strategies to capture the intrinsic properties of biological systems. The "-omic" approaches require disruption of the function of the biological circuit; they provide static information, with low temporal resolution and usually with population averaging that masks fast or variable features at the cellular scale and in a single individual. This data should be correlated with cell behavior as cells are the integrators of biological activity. Cellular dynamics are captured by the in vivo microscopy observation of live organisms. This can be used to reconstruct the 3D + time cell lineage tree to serve as the basis for modeling the organism's multiscale dynamics. We discuss here the progress that has been made in this direction, starting with the reconstruction over time of three-dimensional digital embryos from in toto time-lapse imaging. Digital specimens provide the means for a quantitative description of the development of model organisms that can be stored, shared, and compared. They open the way to in silico experimentation and to a more theoretical approach to biological processes. We show, with some unpublished results, how the proposed methodology can be applied to sea urchin species that have been model organisms in the field of classical embryology and modern developmental biology for over a century.
Collapse
Affiliation(s)
- Barbara Rizzi
- CNRS-MDAM, UPR 3294 and BioEmergences-IBiSA, Institut de Neurobiologie Alfred Fessard, CNRS, Gif-sur-Yvette, France
- Institut des Systèmes Complexes, 57-59 rue Lhomond, Paris, France
| | - Nadine Peyrieras
- CNRS-MDAM, UPR 3294 and BioEmergences-IBiSA, Institut de Neurobiologie Alfred Fessard, CNRS, Gif-sur-Yvette, France
- Institut des Systèmes Complexes, 57-59 rue Lhomond, Paris, France
| |
Collapse
|