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Maéno M, Tanabe M, Ogawa A, Kobayashi H, Izutsu Y, Kato T. Identification and characterization of myeloid cells localized in the tadpole liver cortex in Xenopus laevis. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2024; 156:105178. [PMID: 38599553 DOI: 10.1016/j.dci.2024.105178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Revised: 03/29/2024] [Accepted: 04/07/2024] [Indexed: 04/12/2024]
Abstract
In the present study, using transgenic frogs that express GFP specifically in myeloid cells under the myeloperoxidase enhancer sequence, we found that myeloperoxidase-positive cells are localized in the liver cortex at the late tadpole stages. Immunohistochemical analysis revealed that myelopoiesis in the liver cortex became evident after st. 50 and reached its peak by st. 56. Transplantation experiments indicated that cells with a high density at the liver cortex were derived from the dorso-lateral plate tissue in the neurula embryo. Analysis of smear samples of the cells isolated from collagenase-treated liver tissues of the transgenic tadpoles indicated that myeloid cells were the major population of blood cells in the larval liver and that, in addition to myeloid colonies, erythroid colonies expanded in entire liver after metamorphosis. Cells that were purified from the livers of transgenic tadpoles according to the GFP expression exhibited the multi-lobed nuclei. The results of present study provide evidence that the liver cortex of the Xenopus tadpole is a major site of granulopoiesis.
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Affiliation(s)
- Mitsugu Maéno
- Institute of Science and Technology, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan.
| | - Miki Tanabe
- Faculty of Science, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan
| | - Ayame Ogawa
- Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, TWIns building, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo, 162-8480, Japan; Department of Biology, School of Education, Waseda University, Center for Advanced Biomedical Science, TWIns building, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo, 162-8480, Japan
| | - Haruka Kobayashi
- Graduate School of Science and Technology, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan
| | - Yumi Izutsu
- Institute of Science and Technology, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan
| | - Takashi Kato
- Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, TWIns building, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo, 162-8480, Japan; Department of Biology, School of Education, Waseda University, Center for Advanced Biomedical Science, TWIns building, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo, 162-8480, Japan
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2
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Warfel HC, Wilcoxen TE. Lack of vitamin B12 impairs innate and adaptive immunity of Cuban tree frog (Osteopilus septentrionalis) tadpoles. JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL AND INTEGRATIVE PHYSIOLOGY 2023; 339:878-886. [PMID: 37522473 DOI: 10.1002/jez.2738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 07/10/2023] [Accepted: 07/12/2023] [Indexed: 08/01/2023]
Abstract
Vitamin B12 is a micronutrient required by a variety of organisms for healthy cellular functioning. Despite the systemic effects observed in cases of B12 deficiency, relatively little is known about how vitamin B12 affects immune health, especially in amphibians, which are declining at unprecedented rates. In this study, we tested how supplementing an algae diet with B12 affects the innate and adaptive immunity of Cuban tree frog (Osteopilus septentrionalis) tadpoles. We found that innate immunity, as measured by a bacterial killing assay, was significantly more robust in B12-supplemented tadpoles than control tadpoles, but no significant differences were found in natural antibody production or hematocrit between groups. Adaptive immunity, as measured by Aeromonas hydrophila-specific IgY antibodies, was significantly greater in tadpoles challenged with A. hydrophila and supplemented with B12 than in control tadpoles, those only challenged with A. hydrophila, and those only given B12. Our results suggest that vitamin B12 is an important factor in maintaining a functional immune system in tadpoles, which may also be true for all vertebrates.
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Affiliation(s)
- Hannah C Warfel
- School of Biological Sciences, Illinois State University, Normal, Illinois, USA
- Department of Biology, Millikin University, Decatur, Illinois, USA
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3
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Cowell LM, King M, West H, Broadsmith M, Genever P, Pownall ME, Isaacs HV. Regulation of gene expression downstream of a novel Fgf/Erk pathway during Xenopus development. PLoS One 2023; 18:e0286040. [PMID: 37856433 PMCID: PMC10586617 DOI: 10.1371/journal.pone.0286040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 05/08/2023] [Indexed: 10/21/2023] Open
Abstract
Activation of Map kinase/Erk signalling downstream of fibroblast growth factor (Fgf) tyrosine kinase receptors regulates gene expression required for mesoderm induction and patterning of the anteroposterior axis during Xenopus development. We have proposed that a subset of Fgf target genes are activated in the embyo in response to inhibition of a transcriptional repressor. Here we investigate the hypothesis that Cic (Capicua), which was originally identified as a transcriptional repressor negatively regulated by receptor tyrosine kinase/Erk signalling in Drosophila, is involved in regulating Fgf target gene expression in Xenopus. We characterise Xenopus Cic and show that it is widely expressed in the embryo. Fgf overexpression or ectodermal wounding, both of which potently activate Erk, reduce Cic protein levels in embryonic cells. In keeping with our hypothesis, we show that Cic knockdown and Fgf overexpression have overlapping effects on embryo development and gene expression. Transcriptomic analysis identifies a cohort of genes that are up-regulated by Fgf overexpression and Cic knockdown. We investigate two of these genes as putative targets of the proposed Fgf/Erk/Cic axis: fos and rasl11b, which encode a leucine zipper transcription factor and a ras family GTPase, respectively. We identify Cic consensus binding sites in a highly conserved region of intron 1 in the fos gene and Cic sites in the upstream regions of several other Fgf/Cic co-regulated genes, including rasl11b. We show that expression of fos and rasl11b is blocked in the early mesoderm when Fgf and Erk signalling is inhibited. In addition, we show that fos and rasl11b expression is associated with the Fgf independent activation of Erk at the site of ectodermal wounding. Our data support a role for a Fgf/Erk/Cic axis in regulating a subset of Fgf target genes during gastrulation and is suggestive that Erk signalling is involved in regulating Cic target genes at the site of ectodermal wounding.
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Affiliation(s)
- Laura M. Cowell
- Department of Biology, University of York, Heslington, York, United Kingdom
| | - Michael King
- Department of Biology, University of York, Heslington, York, United Kingdom
| | - Helena West
- Department of Biology, University of York, Heslington, York, United Kingdom
| | - Matthew Broadsmith
- Department of Biology, University of York, Heslington, York, United Kingdom
| | - Paul Genever
- Department of Biology, University of York, Heslington, York, United Kingdom
| | | | - Harry V. Isaacs
- Department of Biology, University of York, Heslington, York, United Kingdom
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4
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Luo W, Dai W, Zhang X, Zheng L, Zhao J, Xie X, Xu Y. Effects of Shigella flexneri exposure on development of Xenopus Tropicals embryo and its immune response. JOURNAL OF HAZARDOUS MATERIALS 2022; 427:128153. [PMID: 34979394 DOI: 10.1016/j.jhazmat.2021.128153] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Revised: 12/16/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
Shigella sp. is a highly infectious intestinal pathogen worthy of serious attention that is widely present in aquaculture water and some other polluted water types and might inhibit embryonic development as a biological pollutant. In this study, acute toxicity tests in which Xenopus tropical embryos were exposed to Shigella flexneri at subpathogenic concentrations (106, 107, and 108 CFU·mL-1) for 96 h were carried out to evaluate toxicity indicators such as mortality, hatching rate, malformation rate and enzyme activity. Meanwhile, the expression of related genes was also studied to reveal the toxicity and mechanism of S. flexneri involved in embryonic development. Under S. flexneri exposure, embryo mortality, heart rate and malformation rate increased, but the hatching rate decreased and even led to embryonic gene misexpression, oxidative stress and immune responses. The results showed that S. flexneri might affect the growth and development of embryos by causing differences in the expression of genes related to embryonic development, oxidative stress and immune disorders. Its target organs are the intestine and heart, whose toxic effects are positively correlated with exposure concentration. This result provides a certain theoretical reference for rational evaluation of the influence of Shigella on the early embryos of amphibians.
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Affiliation(s)
- Wenshi Luo
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Wencan Dai
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
| | - Xiaochun Zhang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Li Zheng
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Jianbin Zhao
- Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Xiao Xie
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Yanbin Xu
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China; Analysis and Test Center, Guangdong University of Technology, Guangzhou 510006, China.
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5
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Pentagna N, Pinheiro da Costa T, Soares Dos Santos Cardoso F, Martins de Almeida F, Blanco Martinez AM, Abreu JG, Levin M, Carneiro K. Epigenetic control of myeloid cells behavior by Histone Deacetylase activity (HDAC) during tissue and organ regeneration in Xenopus laevis. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 114:103840. [PMID: 32858087 DOI: 10.1016/j.dci.2020.103840] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 08/18/2020] [Accepted: 08/18/2020] [Indexed: 06/11/2023]
Abstract
In the present work we have focused on the Histone Deacetylase (HDAC) control of myeloid cells behavior during Xenopus tail regeneration. Here we show that myeloid differentiation is crucial to modulate the regenerative ability of Xenopus tadpoles in a HDAC activity-dependent fashion. HDAC activity inhibition during the first wave of myeloid differentiation disrupted myeloid cells dynamics in the regenerative bud as well the mRNA expression pattern of myeloid markers, such as LURP, MPOX, Spib and mmp7. We also functionally bridge the spatial and temporal dynamics of lipid droplets, the main platform of lipid mediators synthesis in myeloid cells during the inflammatory response, and the regenerative ability of Xenopus tadpoles. In addition, we showed that 15-LOX activity is necessary during tail regeneration. Taken together our results support a role for the epigenetic control of myeloid behavior during tissue and organ regeneration, which may positively impact translational approaches for regenerative medicine.
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Affiliation(s)
- Nathalia Pentagna
- Instituto de Ciências Biomédicas, Universidade Federal Do Rio de Janeiro, Av. Carlos Chagas Filho 373 Bloco F Sala F2-01, Rio de Janeiro, 21941-902, Brazil; Programa de Pós-graduação Em Medicina (Anatomia Patológica), Faculdade de Medicina, Universidade Federal Do Rio de Janeiro, R. Prof. Rodolpho Paulo Rocco, 255, Rio de Janeiro, 21941-590, Brazil.
| | - Thayse Pinheiro da Costa
- Instituto de Ciências Biomédicas, Universidade Federal Do Rio de Janeiro, Av. Carlos Chagas Filho 373 Bloco F Sala F2-01, Rio de Janeiro, 21941-902, Brazil
| | - Fellipe Soares Dos Santos Cardoso
- Programa de Pós-graduação Em Medicina (Anatomia Patológica), Faculdade de Medicina, Universidade Federal Do Rio de Janeiro, R. Prof. Rodolpho Paulo Rocco, 255, Rio de Janeiro, 21941-590, Brazil.
| | - Fernanda Martins de Almeida
- Instituto de Ciências Biomédicas, Universidade Federal Do Rio de Janeiro, Av. Carlos Chagas Filho 373 Bloco F Sala F2-01, Rio de Janeiro, 21941-902, Brazil; Programa de Pós-graduação Em Medicina (Anatomia Patológica), Faculdade de Medicina, Universidade Federal Do Rio de Janeiro, R. Prof. Rodolpho Paulo Rocco, 255, Rio de Janeiro, 21941-590, Brazil.
| | - Ana Maria Blanco Martinez
- Programa de Pós-graduação Em Medicina (Anatomia Patológica), Faculdade de Medicina, Universidade Federal Do Rio de Janeiro, R. Prof. Rodolpho Paulo Rocco, 255, Rio de Janeiro, 21941-590, Brazil.
| | - José Garcia Abreu
- Instituto de Ciências Biomédicas, Universidade Federal Do Rio de Janeiro, Av. Carlos Chagas Filho 373 Bloco F Sala F2-01, Rio de Janeiro, 21941-902, Brazil.
| | - Michael Levin
- Allen Discovery Center, Tufts University, School of Arts and Science, Department of Biology, Suite, 4600, Medford, MA, United States.
| | - Katia Carneiro
- Instituto de Ciências Biomédicas, Universidade Federal Do Rio de Janeiro, Av. Carlos Chagas Filho 373 Bloco F Sala F2-01, Rio de Janeiro, 21941-902, Brazil; Programa de Pós-graduação Em Medicina (Anatomia Patológica), Faculdade de Medicina, Universidade Federal Do Rio de Janeiro, R. Prof. Rodolpho Paulo Rocco, 255, Rio de Janeiro, 21941-590, Brazil.
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6
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Nagata S, Tanuma M. Embryonic Epidermal Lectins in Three Amphibian Species, Rana ornativentris, Bufo japonicus formosus, and Cynops pyrrhogaster. Zoolog Sci 2020; 37:338-345. [PMID: 32729712 DOI: 10.2108/zs190150] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 03/11/2020] [Indexed: 11/17/2022]
Abstract
Intelectins (Itlns) are secretory lectins found in several chordate species that recognize carbohydrates on the bacterial cell surface depending on Ca2 + . In newly hatched larvae of Rana ornativentris (R. orn), Bufo japonicus formosus (B. jpn), and Cynops pyrrhogaster (C. pyr), an anti-Itln monoclonal antibody (mAb) labeled a subset of epidermal cells in whole-mount immunocytochemical assays. In western blot analyses, the mAb identified protein bands at approximately 33-37 kDa in the larval extracts and concentrated larval culture media. Using RT-PCR and RACE techniques, we isolated cDNAs from newly hatched larvae that encoded proteins of 343 (R. orn), 336 (B. jpn), and 337 (C. pyr) amino acids having 70%, 71%, and 60% identities with that of the Xenopus laevis embryonic epidermal lectin (XEEL), respectively. The proteins, designated REEL, BEEL, and CEEL, showed characteristics conserved among reported Itln proteins, and their amino acid sequences following the signal peptides were identical to those of the N-terminal peptides determined on Itln proteins in the respective larval extracts. Recombinant REEL (rREEL), rBEEL, and rCEEL proteins produced by HEK-293T cells were homo-oligomers of 34-37 kDa subunit peptides, which were similar to the Itlns found in the newly hatched larvae. The rEELs showed carbohydrate-binding specificities similar to that of XEEL and agglutinated Escherichia coli and Staphylococcus aureus cells depending on Ca2 + . These results suggest that REEL, BEEL, and CEEL are Itlns produced and secreted by epidermal cells of R. orn, B. jpn, and C. pyr larvae, respectively, and that Itlns have a conserved role as pathogen recognition molecules in the larval innate immune system.
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Affiliation(s)
- Saburo Nagata
- Department of Chemical and Biological Sciences, Faculty of Science, Japan Women's University, Mejirodai 2-8-1, Bunkyoku, Tokyo 112-8681, Japan,
| | - Mayuko Tanuma
- Department of Chemical and Biological Sciences, Faculty of Science, Japan Women's University, Mejirodai 2-8-1, Bunkyoku, Tokyo 112-8681, Japan
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7
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An in vivo brain-bacteria interface: the developing brain as a key regulator of innate immunity. NPJ Regen Med 2020; 5:2. [PMID: 32047653 PMCID: PMC7000827 DOI: 10.1038/s41536-020-0087-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Accepted: 12/20/2019] [Indexed: 01/11/2023] Open
Abstract
Infections have numerous effects on the brain. However, possible roles of the brain in protecting against infection, and the developmental origin and role of brain signaling in immune response, are largely unknown. We exploited a unique Xenopus embryonic model to reveal control of innate immune response to pathogenic E. coli by the developing brain. Using survival assays, morphological analysis of innate immune cells and apoptosis, and RNA-seq, we analyzed combinations of infection, brain removal, and tail-regenerative response. Without a brain, survival of embryos injected with bacteria decreased significantly. The protective effect of the developing brain was mediated by decrease of the infection-induced damage and of apoptosis, and increase of macrophage migration, as well as suppression of the transcriptional consequences of the infection, all of which decrease susceptibility to pathogen. Functional and pharmacological assays implicated dopamine signaling in the bacteria–brain–immune crosstalk. Our data establish a model that reveals the very early brain to be a central player in innate immunity, identify the developmental origins of brain–immune interactions, and suggest several targets for immune therapies.
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8
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Aztekin C, Hiscock TW, Butler R, De Jesús Andino F, Robert J, Gurdon JB, Jullien J. The myeloid lineage is required for the emergence of a regeneration-permissive environment following Xenopus tail amputation. Development 2020; 147:dev.185496. [PMID: 31988186 PMCID: PMC7033733 DOI: 10.1242/dev.185496] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 01/13/2020] [Indexed: 01/02/2023]
Abstract
Regeneration-competent vertebrates are considered to suppress inflammation faster than non-regenerating ones. Hence, understanding the cellular mechanisms affected by immune cells and inflammation can help develop strategies to promote tissue repair and regeneration. Here, we took advantage of naturally occurring tail regeneration-competent and -incompetent developmental stages of Xenopus tadpoles. We first establish the essential role of the myeloid lineage for tail regeneration in the regeneration-competent tadpoles. We then reveal that upon tail amputation there is a myeloid lineage-dependent change in amputation-induced apoptosis levels, which in turn promotes tissue remodelling, and ultimately leads to the relocalization of the regeneration-organizing cells responsible for progenitor proliferation. These cellular mechanisms failed to be executed in regeneration-incompetent tadpoles. We demonstrate that regeneration incompetency is characterized by inflammatory myeloid cells whereas regeneration competency is associated with reparative myeloid cells. Moreover, treatment of regeneration-incompetent tadpoles with immune-suppressing drugs restores myeloid lineage-controlled cellular mechanisms. Collectively, our work reveals the effects of differential activation of the myeloid lineage on the creation of a regeneration-permissive environment and could be further exploited to devise strategies for regenerative medicine purposes. Summary:Xenopus tail regeneration requires a hierarchy of cellular events initiated by the myeloid lineage and culminating in the mobilization of regeneration-organizing cells.
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Affiliation(s)
- Can Aztekin
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, CB1 2QN, UK .,Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, UK
| | - Tom W Hiscock
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, CB1 2QN, UK.,Cancer Research UK Cambridge Institute, University of Cambridge, Cambridge, CB2 0RE, UK
| | - Richard Butler
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, CB1 2QN, UK
| | - Francisco De Jesús Andino
- Department of Microbiology & Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - Jacques Robert
- Department of Microbiology & Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
| | - John B Gurdon
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, CB1 2QN, UK.,Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, UK
| | - Jerome Jullien
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, CB1 2QN, UK .,Department of Zoology, University of Cambridge, Cambridge, CB2 3EJ, UK.,Nantes Université, Inserm, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, F-44000 Nantes, France
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9
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Paraiso KD, Blitz IL, Zhou JJ, Cho KWY. Morpholinos Do Not Elicit an Innate Immune Response during Early Xenopus Embryogenesis. Dev Cell 2020; 49:643-650.e3. [PMID: 31112700 DOI: 10.1016/j.devcel.2019.04.019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 03/14/2019] [Accepted: 04/16/2019] [Indexed: 02/06/2023]
Abstract
It has recently been reported that a common side effect of translation-blocking morpholino antisense oligonucleotides is the induction of a set of innate immune response genes in Xenopus embryos and that splicing-blocking morpholinos lead to unexpected off-target mis-splicing events. Here, we present an analysis of all publicly available Xenopus RNA sequencing (RNA-seq) data in a reexamination of the effects of translation-blocking morpholinos on the innate immune response. Our analysis does not support the authors' general conclusion, which was based on a limited number of RNA-seq datasets. Moreover, the strong induction of an immune response appears to be specific to the tbxt/tbxt2 morpholinos. The more comprehensive study presented here indicates that using morpholinos for targeted gene knockdowns remains of considerable value for the rapid identification of gene function.
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Affiliation(s)
- Kitt D Paraiso
- Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA
| | - Ira L Blitz
- Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Jeff J Zhou
- Developmental and Cell Biology, University of California, Irvine, CA, USA
| | - Ken W Y Cho
- Developmental and Cell Biology, University of California, Irvine, CA, USA; Center for Complex Biological Systems, University of California, Irvine, CA, USA.
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10
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Balic A, Chintoan-Uta C, Vohra P, Sutton KM, Cassady-Cain RL, Hu T, Donaldson DS, Stevens MP, Mabbott NA, Hume DA, Sang HM, Vervelde L. Antigen Sampling CSF1R-Expressing Epithelial Cells Are the Functional Equivalents of Mammalian M Cells in the Avian Follicle-Associated Epithelium. Front Immunol 2019; 10:2495. [PMID: 31695701 PMCID: PMC6817575 DOI: 10.3389/fimmu.2019.02495] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 10/07/2019] [Indexed: 12/11/2022] Open
Abstract
The follicle-associated epithelium (FAE) is a specialized structure that samples luminal antigens and transports them into mucosa-associated lymphoid tissues (MALT). In mammals, transcytosis of antigens across the gut epithelium is performed by a subset of FAE cells known as M cells. Here we show that colony-stimulating factor 1 receptor (CSF1R) is expressed by a subset of cells in the avian bursa of Fabricius FAE. Expression was initially detected using a CSF1R-reporter transgene that also label subsets of bursal macrophages. Immunohistochemical detection using a specific monoclonal antibody confirmed abundant expression of CSF1R on the basolateral membrane of FAE cells. CSF1R-transgene expressing bursal FAE cells were enriched for expression of markers previously reported as putative M cell markers, including annexin A10 and CD44. They were further distinguished from a population of CSF1R-transgene negative epithelial cells within FAE by high apical F-actin expression and differential staining with the lectins jacalin, PHA-L and SNA. Bursal FAE cells that express the CSF1R-reporter transgene were responsible for the bulk of FAE transcytosis of labeled microparticles in the size range 0.02-0.1 μm. Unlike mammalian M cells, they did not readily take up larger bacterial sized microparticles (0.5 μm). Their role in uptake of bacteria was tested using Salmonella, which can enter via M cells in mammals. Labeled Salmonella enterica serovar Typhimurium entered bursal tissue via the FAE. Entry was partially dependent upon Type III secretion system-1. However, the majority of invading bacteria were localized to CSF1R-negative FAE cells and in resident phagocytes that express the phosphatidylserine receptor TIM4. CSF1R-expressing FAE cells in infected follicles showed evidence of cell death and shedding into the bursal lumen. In mammals, CSF1R expression in the gut is restricted to macrophages which only indirectly control M cell differentiation. The novel expression of CSF1R in birds suggests that these functional equivalents to mammalian M cells may have different ontological origins and their development and function are likely to be regulated by different growth factors.
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Affiliation(s)
- Adam Balic
- Division of Developmental Biology, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom.,Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
| | - Cosmin Chintoan-Uta
- Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
| | - Prerna Vohra
- Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
| | - Kate M Sutton
- Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
| | - Robin L Cassady-Cain
- Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
| | - Tuan Hu
- Division of Developmental Biology, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - David S Donaldson
- Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
| | - Mark P Stevens
- Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
| | - Neil A Mabbott
- Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
| | - David A Hume
- Division of Genetics and Genomics, The Roslin Institute, University of Edinburgh, Easter Bush, United Kingdom
| | - Helen M Sang
- Division of Developmental Biology, The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom
| | - Lonneke Vervelde
- Division of Infection and Immunity, The Roslin Institute, University of Edinburgh, Easter Bush, Edinburgh, United Kingdom
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11
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Suzuki N, Hirano K, Ogino H, Ochi H. Arid3a regulates nephric tubule regeneration via evolutionarily conserved regeneration signal-response enhancers. eLife 2019; 8:43186. [PMID: 30616715 PMCID: PMC6324879 DOI: 10.7554/elife.43186] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Accepted: 12/18/2018] [Indexed: 12/15/2022] Open
Abstract
Amphibians and fish have the ability to regenerate numerous tissues, whereas mammals have a limited regenerative capacity. Despite numerous developmental genes becoming reactivated during regeneration, an extensive analysis is yet to be performed on whether highly regenerative animals utilize unique cis-regulatory elements for the reactivation of genes during regeneration and how such cis-regulatory elements become activated. Here, we screened regeneration signal-response enhancers at the lhx1 locus using Xenopus and found that the noncoding elements conserved from fish to human function as enhancers in the regenerating nephric tubules. A DNA-binding motif of Arid3a, a component of H3K9me3 demethylases, was commonly found in RSREs. Arid3a binds to RSREs and reduces the H3K9me3 levels. It promotes cell cycle progression and causes the outgrowth of nephric tubules, whereas the conditional knockdown of arid3a using photo-morpholino inhibits regeneration. These results suggest that Arid3a contributes to the regeneration of nephric tubules by decreasing H3K9me3 on RSREs.
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Affiliation(s)
- Nanoka Suzuki
- Institute for Promotion of Medical Science Research, Yamagata University, Faculty of Medicine, Yamagata, Japan
| | - Kodai Hirano
- Institute for Promotion of Medical Science Research, Yamagata University, Faculty of Medicine, Yamagata, Japan
| | - Hajime Ogino
- Amphibian Research Center, Hiroshima University, Higashi-hiroshima, Japan
| | - Haruki Ochi
- Institute for Promotion of Medical Science Research, Yamagata University, Faculty of Medicine, Yamagata, Japan
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12
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Hassnain Waqas SF, Noble A, Hoang AC, Ampem G, Popp M, Strauß S, Guille M, Röszer T. Adipose tissue macrophages develop from bone marrow-independent progenitors in Xenopus laevis and mouse. J Leukoc Biol 2017; 102:845-855. [PMID: 28642277 PMCID: PMC5574031 DOI: 10.1189/jlb.1a0317-082rr] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 05/26/2017] [Accepted: 05/27/2017] [Indexed: 12/14/2022] Open
Abstract
ATMs have a metabolic impact in mammals as they contribute to metabolically harmful AT inflammation. The control of the ATM number may have therapeutic potential; however, information on ATM ontogeny is scarce. Whereas it is thought that ATMs develop from circulating monocytes, various tissue-resident Mϕs are capable of self-renewal and develop from BM-independent progenitors without a monocyte intermediate. Here, we show that amphibian AT contains self-renewing ATMs that populate the AT before the establishment of BM hematopoiesis. Xenopus ATMs develop from progenitors of aVBI. In the mouse, a significant amount of ATM develops from the yolk sac, the mammalian equivalent of aVBI. In summary, this study provides evidence for a prenatal origin of ATMs and shows that the study of amphibian ATMs can enhance the understanding of the role of the prenatal environment in ATM development.
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Affiliation(s)
| | - Anna Noble
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Anh C Hoang
- Institute of Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Grace Ampem
- Institute of Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Manuela Popp
- Institute of Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany
| | - Sarah Strauß
- Ambystoma Mexicanum Bioregeneration Center, Department of Plastic, Aesthetic, Hand and Reconstructive Surgery, Hannover Medical School, Medizinische Hochschule Hannover, Hannover, Germany
| | - Matthew Guille
- European Xenopus Resource Centre, School of Biological Sciences, University of Portsmouth, Portsmouth, United Kingdom
| | - Tamás Röszer
- Institute of Comparative Molecular Endocrinology, University of Ulm, Ulm, Germany;
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13
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Chang J, Baker J, Wills A. Transcriptional dynamics of tail regeneration in Xenopus tropicalis. Genesis 2017; 55. [PMID: 28095651 DOI: 10.1002/dvg.23015] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 12/12/2016] [Accepted: 12/13/2016] [Indexed: 12/20/2022]
Abstract
In contrast to humans, many amphibians are able to rapidly and completely regenerate complex tissues, including entire appendages. Following tail amputation, Xenopus tropicalis tadpoles quickly regenerate muscle, spinal cord, cartilage, vasculature and skin, all properly patterned in three dimensions. To better understand the molecular basis of this regenerative competence, we performed a transcriptional analysis of the first 72 h of tail regeneration using RNA-Seq. Our analysis refines the windows during which many key biological signaling processes act in regeneration, including embryonic patterning signals, immune responses, bioelectrical signaling and apoptosis. Our work provides a deep database for researchers interested in appendage regeneration, and points to new avenues for further study.
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Affiliation(s)
- Jessica Chang
- Department of Genetics, Stanford University, Stanford, California, 94305
| | - Julie Baker
- Department of Genetics, Stanford University, Stanford, California, 94305.,Department of Obstetrics and Gynecology, Stanford University, Stanford, California, 94305
| | - Andrea Wills
- Department of Biochemistry, University of Washington, Seattle, Washington, 98195
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14
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Imai Y, Ishida K, Nemoto M, Nakata K, Kato T, Maéno M. Multiple origins of embryonic and tadpole myeloid cells in Xenopus laevis. Cell Tissue Res 2017; 369:341-352. [PMID: 28374149 DOI: 10.1007/s00441-017-2601-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 02/23/2017] [Indexed: 11/25/2022]
Abstract
Rabbit anti-serum against a myeloid-cell-specific peroxidase (Mpo) of Xenopus laevis was generated to identify myeloid cells in adult and larval animals. Smears of blood samples from adult hematopoietic organs were co-stained with Mpo and with XL-2, a mouse monoclonal antibody against a leukocyte common antigen. Lymphocytes found in the thymus and spleen were XL-2+Mpo- and granulocytes found in peripheral blood cells and the spleen were XL-2+Mpo+, indicating that double-staining with these two antibodies allowed classification of the leukocyte lineages. Immunohistochemical analysis of larval organs showed that XL-2+Mpo- cells were scattered throughout the liver, whereas XL-2+Mpo+ cells were present mainly in the cortex region. Interestingly, a cluster of XL-2+Mpo+ cells was found in the region of the larval mesonephric rudiment. The ratio of XL-2+Mpo+ cells to XL-2+ cells in the mesonephric region was approximately 80%, which was much higher than that found in other hematopoietic organs. In order to elucidate the embryonic origin of the myeloid cells in the tadpole mesonephros, grafting experiments between X. laevis and X. borealis embryos were performed to trace the X. borealis cells as donor cells. Among the embryonic tissues examined, the tailbud tissue at the early neurula stage contributed greatly to the myeloid cluster in the mesonephric region at stage 48. Therefore, at least four independent origins of the myeloid cell population can be traced in the Xenopus embryo.
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Affiliation(s)
- Yasutaka Imai
- Graduate School of Science and Technology, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan
| | - Keisuke Ishida
- Graduate School of Science and Technology, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan
| | - Maya Nemoto
- Department of Biology, Faculty of Science, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan
| | - Keisuke Nakata
- Graduate School of Science and Technology, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan
| | - Takashi Kato
- Department of Biology, School of Education, Center for Advanced Biomedical Science, Waseda University, TWIns building, 2-2 Wakamatsu-cho, Shinjuku-ku, Tokyo, 162-8480, Japan
| | - Mitsugu Maéno
- Graduate School of Science and Technology, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan.
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15
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Takacs E, Boto P, Simo E, Csuth TI, Toth BM, Raveh-Amit H, Pap A, Kovács EG, Kobolak J, Benkö S, Dinnyes A, Szatmari I. Immunogenic Dendritic Cell Generation from Pluripotent Stem Cells by Ectopic Expression of Runx3. THE JOURNAL OF IMMUNOLOGY 2016; 198:239-248. [DOI: 10.4049/jimmunol.1600034] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Accepted: 10/28/2016] [Indexed: 11/19/2022]
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16
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Li J, Zhang S, Amaya E. The cellular and molecular mechanisms of tissue repair and regeneration as revealed by studies in Xenopus. ACTA ACUST UNITED AC 2016; 3:198-208. [PMID: 27800170 PMCID: PMC5084359 DOI: 10.1002/reg2.69] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 09/09/2016] [Accepted: 09/12/2016] [Indexed: 12/16/2022]
Abstract
Survival of any living organism critically depends on its ability to repair and regenerate damaged tissues and/or organs during its lifetime following injury, disease, or aging. Various animal models from invertebrates to vertebrates have been used to investigate the molecular and cellular mechanisms of wound healing and tissue regeneration. It is hoped that such studies will form the framework for identifying novel clinical treatments that will improve the healing and regenerative capacity of humans. Amongst these models, Xenopus stands out as a particularly versatile and powerful system. This review summarizes recent findings using this model, which have provided fundamental knowledge of the mechanisms responsible for efficient and perfect tissue repair and regeneration.
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Affiliation(s)
- Jingjing Li
- Division of Cell Matrix Biology and Regenerative MedicineSchool of Biological SciencesFaculty of BiologyMedicine and HealthUniversity of ManchesterManchesterM13 9PTUK
| | - Siwei Zhang
- Division of Cell Matrix Biology and Regenerative MedicineSchool of Biological SciencesFaculty of BiologyMedicine and HealthUniversity of ManchesterManchesterM13 9PTUK
| | - Enrique Amaya
- Division of Cell Matrix Biology and Regenerative MedicineSchool of Biological SciencesFaculty of BiologyMedicine and HealthUniversity of ManchesterManchesterM13 9PTUK
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17
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Grayfer L, Robert J. Amphibian macrophage development and antiviral defenses. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 58:60-7. [PMID: 26705159 PMCID: PMC4775336 DOI: 10.1016/j.dci.2015.12.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 12/12/2015] [Accepted: 12/13/2015] [Indexed: 05/29/2023]
Abstract
Macrophage lineage cells represent the cornerstone of vertebrate physiology and immune defenses. In turn, comparative studies using non-mammalian animal models have revealed that evolutionarily distinct species have adopted diverse molecular and physiological strategies for controlling macrophage development and functions. Notably, amphibian species present a rich array of physiological and environmental adaptations, not to mention the peculiarity of metamorphosis from larval to adult stages of development, involving drastic transformation and differentiation of multiple new tissues. Thus it is not surprising that different amphibian species and their respective tadpole and adult stages have adopted unique hematopoietic strategies. Accordingly and in order to establish a more comprehensive view of these processes, here we review the hematopoietic and monopoietic strategies observed across amphibians, describe the present understanding of the molecular mechanisms driving amphibian, an in particular Xenopus laevis macrophage development and functional polarization, and discuss the roles of macrophage-lineage cells during ranavirus infections.
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Affiliation(s)
- Leon Grayfer
- Department of Biological Sciences, George Washington University, Washington, DC, USA
| | - Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY, USA.
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18
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Agricola ZN, Jagpal AK, Allbee AW, Prewitt AR, Shifley ET, Rankin SA, Zorn AM, Kenny AP. Identification of genes expressed in the migrating primitive myeloid lineage of Xenopus laevis. Dev Dyn 2015; 245:47-55. [PMID: 26264370 DOI: 10.1002/dvdy.24314] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 06/23/2015] [Accepted: 07/13/2015] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND During primitive hematopoiesis in Xenopus, cebpa and spib expressing myeloid cells emerge from the anterior ventral blood island. Primitive myeloid cells migrate throughout the embryo and are critical for immunity, healing, and development. Although definitive hematopoiesis has been studied extensively, molecular mechanisms leading to the migration of primitive myelocytes remain poorly understood. We hypothesized these cells have specific extracellular matrix modifying and cell motility gene expression. RESULTS In situ hybridization screens of transcripts expressed in Xenopus foregut mesendoderm at stage 23 identified seven genes with restricted expression in primitive myeloid cells: destrin; coronin actin binding protein, 1a; formin-like 1; ADAM metallopeptidase domain 28; cathepsin S; tissue inhibitor of metalloproteinase-1; and protein tyrosine phosphatase nonreceptor 6. A detailed in situ hybridization analysis revealed these genes are initially expressed in the aVBI but become dispersed throughout the embryo as the primitive myeloid cells become migratory, similar to known myeloid markers. Morpholino-mediated loss-of-function and mRNA-mediated gain-of-function studies revealed the identified genes are downstream of Spib.a and Cebpa, key transcriptional regulators of the myeloid lineage. CONCLUSIONS We have identified genes specifically expressed in migratory primitive myeloid progenitors, providing tools to study how different gene networks operate in these primitive myelocytes during development and immunity.
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Affiliation(s)
- Zachary N Agricola
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Amrita K Jagpal
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Andrew W Allbee
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Allison R Prewitt
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Emily T Shifley
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Scott A Rankin
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Aaron M Zorn
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Developmental Biology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
| | - Alan P Kenny
- Perinatal Institute, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio.,Division of Neonatology, Cincinnati Children's Hospital Research Foundation and Department of Pediatrics College of Medicine, University of Cincinnati, Cincinnati, Ohio
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19
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Meadows SM, Cleaver O. Annexin A3 Regulates Early Blood Vessel Formation. PLoS One 2015; 10:e0132580. [PMID: 26182056 PMCID: PMC4504506 DOI: 10.1371/journal.pone.0132580] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 06/16/2015] [Indexed: 12/02/2022] Open
Abstract
Annexins are a large family of calcium binding proteins that associate with cell membrane phospholipids and are involved in various cellular processes including endocytosis, exocytosis and membrane-cytoskeletal organization. Despite studies on numerous Annexin proteins, the function of Annexin A3 (Anxa3) is largely unknown. Our studies identify Anxa3 as a unique marker of the endothelial and myeloid cell lineages of Xenopus laevis during development. Anxa3 transcripts are also detected in endothelial cells (ECs) of zebrafish and mouse embryos, suggesting an important evolutionary function during formation of blood vessels. Indeed, Anxa3 loss-of-function experiments in frog embryos reveal its critical role during the morphogenesis of early blood vessels, as angioblasts in MO injected embryos fail to form vascular cords. Furthermore, in vitro experiments in mammalian cells identify a role for Anxa3 in EC migration. Our results are the first to reveal an in vivo function for Anxa3 during vascular development and represent a previously unexplored aspect of annexin biology.
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Affiliation(s)
- Stryder M. Meadows
- Department of Cell and Molecular Biology, Tulane University, 2000 Percival Stern Hall, 6400 Freret St., New Orleans, LA, United States of America
- * E-mail:
| | - Ondine Cleaver
- Department of Molecular Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, Texas, United States of America
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20
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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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21
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Ogawa-Otomo A, Kurisaki A, Ito Y. Aminolevulinate synthase 2 mediates erythrocyte differentiation by regulating larval globin expression during Xenopus primary hematopoiesis. Biochem Biophys Res Commun 2014; 456:476-81. [PMID: 25482442 DOI: 10.1016/j.bbrc.2014.11.110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Accepted: 11/27/2014] [Indexed: 10/24/2022]
Abstract
Hemoglobin synthesis by erythrocytes continues throughout a vertebrate's lifetime. The mechanism of mammalian heme synthesis has been studied for many years; aminolevulinate synthase 2 (ALAS2), a heme synthetase, is associated with X-linked dominant protoporphyria in humans. Amphibian and mammalian blood cells differ, but little is known about amphibian embryonic hemoglobin synthesis. We investigated the function of the Xenopus alas2 gene (Xalas2) in primitive amphibian erythrocytes and found that it is first expressed in primitive erythroid cells before hemoglobin alpha 3 subunit (hba3) during primary hematopoiesis and in the posterior ventral blood islands at the tailbud stage. Xalas2 is not expressed during secondary hematopoiesis in the dorsal lateral plate. Hemoglobin was barely detectable by o-dianisidine staining and hba3 transcript levels decreased in Xalas2-knockdown embryos. These results suggest that Xalas2 might be able to synthesize hemoglobin during hematopoiesis and mediate erythrocyte differentiation by regulating hba3 expression in Xenopus laevis.
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Affiliation(s)
- Asako Ogawa-Otomo
- Graduate School of Life and Environmental Sciences, The University of Tsukuba, Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan; Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan
| | - Akira Kurisaki
- Graduate School of Life and Environmental Sciences, The University of Tsukuba, Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan; Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan
| | - Yuzuru Ito
- Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Central 4, Higashi 1-1-1, Tsukuba, Ibaraki 305-8562, Japan.
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22
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Sakata H, Maéno M. Nkx2.5 is involved in myeloid cell differentiation at anterior ventral blood islands in the Xenopus embryo. Dev Growth Differ 2014; 56:544-54. [PMID: 25283688 DOI: 10.1111/dgd.12155] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 07/22/2014] [Accepted: 07/23/2014] [Indexed: 11/28/2022]
Abstract
We have shown previously that two populations of myeloid cells emerge in the anterior and posterior ventral blood islands (aVBI and pVBI) at the different stages in Xenopus laevis embryo. In order to elucidate the regulatory mechanism of myeloid cell differentiation in the aVBI, we examined the role of Nkx2.5, an essential transcription factor for heart differentiation, in regulation of the myeloid cell differentiation in this region. Knockdown of endogenous Nkx2.5 by introducing MO into the dorsal marginal zone (DMZ) suppressed the expression of MHCα as well as that of mpo and spib in the resultant embryos and in DMZ explants made from the injected embryos. Expression of c/ebpα was less affected in the embryos injected with Nkx2.5 MO. The effect of Nkx2.5 MO in myeloid cell differentiation was recovered by coinjection of nkx2.5 or c/ebpα mRNA, indicating that Nkx2.5 functions at the same or the upper level of C/EBPα for the specification of myeloid cells. An attempt to identify transcription factors for myeloid cell differentiation in ventral marginal zone (VMZ) explants demonstrated that coinjection of two transcription factors out of three factors, namely C/EBPα, Nkx2.5 and GATA4, was sufficient to induce a certain amount of mpo expression. We suggest that C/EBPα is an unequivocal factor for myeloid cell differentiation in the aVBI and that Nkx2.5 and GATA4 cooperate with C/EBPα for promotion of myeloid cell differentiation.
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Affiliation(s)
- Hiroyuki Sakata
- Graduate School of Science and Technology, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata, 950-2181, Japan
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23
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Balic A, Garcia-Morales C, Vervelde L, Gilhooley H, Sherman A, Garceau V, Gutowska MW, Burt DW, Kaiser P, Hume DA, Sang HM. Visualisation of chicken macrophages using transgenic reporter genes: insights into the development of the avian macrophage lineage. Development 2014; 141:3255-65. [PMID: 25063453 PMCID: PMC4197536 DOI: 10.1242/dev.105593] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We have generated the first transgenic chickens in which reporter genes are expressed in a specific immune cell lineage, based upon control elements of the colony stimulating factor 1 receptor (CSF1R) locus. The Fms intronic regulatory element (FIRE) within CSF1R is shown to be highly conserved in amniotes and absolutely required for myeloid-restricted expression of fluorescent reporter genes. As in mammals, CSF1R-reporter genes were specifically expressed at high levels in cells of the macrophage lineage and at a much lower level in granulocytes. The cell lineage specificity of reporter gene expression was confirmed by demonstration of coincident expression with the endogenous CSF1R protein. In transgenic birds, expression of the reporter gene provided a defined marker for macrophage-lineage cells, identifying the earliest stages in the yolk sac, throughout embryonic development and in all adult tissues. The reporter genes permit detailed and dynamic visualisation of embryonic chicken macrophages. Chicken embryonic macrophages are not recruited to incisional wounds, but are able to recognise and phagocytose microbial antigens.
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Affiliation(s)
- Adam Balic
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Carla Garcia-Morales
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Lonneke Vervelde
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Hazel Gilhooley
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Adrian Sherman
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Valerie Garceau
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Maria W Gutowska
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - David W Burt
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Pete Kaiser
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - David A Hume
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
| | - Helen M Sang
- The Roslin Institute and Royal (Dick) School of Veterinary Sciences, University of Edinburgh, Easter Bush, Midlothian EH25 9RG, UK
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24
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Abstract
Cell migration is a fundamental process that occurs during embryo development. Classic studies using in vitro culture systems have been instrumental in dissecting the principles of cell motility and highlighting how cells make use of topographical features of the substrate, cell-cell contacts, and chemical and physical environmental signals to direct their locomotion. Here, we review the guidance principles of in vitro cell locomotion and examine how they control directed cell migration in vivo during development. We focus on developmental examples in which individual guidance mechanisms have been clearly dissected, and for which the interactions among guidance cues have been explored. We also discuss how the migratory behaviours elicited by guidance mechanisms generate the stereotypical patterns of migration that shape tissues in the developing embryo.
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Affiliation(s)
- Germán Reig
- Anatomy and Developmental Biology Program, Institute of Biomedical Sciences
- Biomedical Neuroscience Institute, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago 8380453, Chile
| | - Eduardo Pulgar
- Anatomy and Developmental Biology Program, Institute of Biomedical Sciences
- Biomedical Neuroscience Institute, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago 8380453, Chile
| | - Miguel L. Concha
- Anatomy and Developmental Biology Program, Institute of Biomedical Sciences
- Biomedical Neuroscience Institute, Facultad de Medicina, Universidad de Chile, Independencia 1027, Santiago 8380453, Chile
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25
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Lim JC, Kurihara S, Tamaki R, Mashima Y, Maéno M. Expression and localization of Rdd proteins in Xenopus embryo. Anat Cell Biol 2014; 47:18-27. [PMID: 24693479 PMCID: PMC3968263 DOI: 10.5115/acb.2014.47.1.18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 12/10/2013] [Accepted: 02/07/2014] [Indexed: 11/27/2022] Open
Abstract
The previous study has shown that repeated D domain-like (Rdd) proteins, a group of novel secretory proteins consisting of repeated domains of a cysteine-rich sequence, are involved in the process of blood vessel formation in Xenopus embryo. We performed further experiments to examine the localization of Rdd proteins in embryogenesis. Detection of tagged Rdd proteins expressed in blastomeres showed that Rdd proteins formed a high molecular weight complex and existed in the extracellular space. A rabbit antibody against the Rdd synthetic peptide identified a single band of 28 kD in embryonic tissue extract. By whole-mount immunostaining analysis, signal was detected in the regions of inter-somites, vitelline veins, and branchial arches at the tailbud stage. Staining of Rdd was remarkably reduced in the embryos injected with vascular endothelial growth factor Morpholino. We suggest that Rdd proteins interact with a molecule(s) associated with vascular precursor cells.
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Affiliation(s)
- Jong-Chan Lim
- Graduate School of Science and Technology, Niigata University, Niigata, Japan
| | - Sayaka Kurihara
- Graduate School of Science and Technology, Niigata University, Niigata, Japan
| | - Rie Tamaki
- Graduate School of Science and Technology, Niigata University, Niigata, Japan
| | - Yutaka Mashima
- Graduate School of Science and Technology, Niigata University, Niigata, Japan
| | - Mitsugu Maéno
- Graduate School of Science and Technology, Niigata University, Niigata, Japan
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BMP-mediated specification of the erythroid lineage suppresses endothelial development in blood island precursors. Blood 2013; 122:3929-39. [PMID: 24100450 DOI: 10.1182/blood-2013-03-490045] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The developmental relationship between the blood and endothelial cell (EC) lineages remains unclear. In the extra-embryonic blood islands of birds and mammals, ECs and blood cells are closely intermixed, and blood island precursor cells in the primitive streak express many of the same molecular markers, leading to the suggestion that both lineages arise from a common precursor, called the hemangioblast. Cells within the blood island of Xenopus also coexpress predifferentiation markers of the blood and EC lineages. However, using multiple assays, we find that precursor cells in the Xenopus blood island do not normally differentiate into ECs, suggesting that classic hemangioblasts are rare or nonexistent in Xenopus. What prevents these precursor cells from developing into mature ECs? We have found that bone morphogenetic protein (BMP) signaling is essential for erythroid differentiation, and in the absence of BMP signaling, precursor cells adopt an EC fate. Furthermore, inhibition of the erythroid transcription pathway leads to endothelial differentiation. Our results indicate that bipotential endothelial/erythroid precursor cells do indeed exist in the Xenopus blood island, but BMP signaling normally acts to constrain EC fate. More generally, these results provide evidence that commitment to the erythroid lineage limits development of bipotential precursors toward an endothelial fate.
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27
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Meier NT, Haslam IS, Pattwell DM, Zhang GY, Emelianov V, Paredes R, Debus S, Augustin M, Funk W, Amaya E, Kloepper JE, Hardman MJ, Paus R. Thyrotropin-releasing hormone (TRH) promotes wound re-epithelialisation in frog and human skin. PLoS One 2013; 8:e73596. [PMID: 24023889 PMCID: PMC3759422 DOI: 10.1371/journal.pone.0073596] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 07/29/2013] [Indexed: 01/09/2023] Open
Abstract
There remains a critical need for new therapeutics that promote wound healing in patients suffering from chronic skin wounds. This is, in part, due to a shortage of simple, physiologically and clinically relevant test systems for investigating candidate agents. The skin of amphibians possesses a remarkable regenerative capacity, which remains insufficiently explored for clinical purposes. Combining comparative biology with a translational medicine approach, we report the development and application of a simple ex vivo frog (Xenopus tropicalis) skin organ culture system that permits exploration of the effects of amphibian skin-derived agents on re-epithelialisation in both frog and human skin. Using this amphibian model, we identify thyrotropin-releasing hormone (TRH) as a novel stimulant of epidermal regeneration. Moving to a complementary human ex vivo wounded skin assay, we demonstrate that the effects of TRH are conserved across the amphibian-mammalian divide: TRH stimulates wound closure and formation of neo-epidermis in organ-cultured human skin, accompanied by increased keratinocyte proliferation and wound healing-associated differentiation (cytokeratin 6 expression). Thus, TRH represents a novel, clinically relevant neuroendocrine wound repair promoter that deserves further exploration. These complementary frog and human skin ex vivo assays encourage a comparative biology approach in future wound healing research so as to facilitate the rapid identification and preclinical testing of novel, evolutionarily conserved, and clinically relevant wound healing promoters.
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Affiliation(s)
- Natalia T. Meier
- Department of Dermatology, University of Luebeck, Luebeck, Germany
- Department of Pathology, University of Luebeck, Luebeck, Germany
| | - Iain S. Haslam
- The Dermatology Centre, Salford Royal NHS Foundation Trust and Institute of Inflammation and Repair, School of Translational Medicine, University of Manchester, Manchester, United Kingdom
- * E-mail:
| | - David M. Pattwell
- The Dermatology Centre, Salford Royal NHS Foundation Trust and Institute of Inflammation and Repair, School of Translational Medicine, University of Manchester, Manchester, United Kingdom
| | - Guo-You Zhang
- Department of Dermatology, University of Luebeck, Luebeck, Germany
- Department of Hand and Plastic Surgery, the Second Affiliated Hospital of Wenzhou Medical College, Wenzhou, Zhejiang Province, China
| | | | - Roberto Paredes
- The Healing Foundation Centre, Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Sebastian Debus
- Department of Vascular Surgery, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Matthias Augustin
- Center for Dermatological Research, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | | | - Enrique Amaya
- The Healing Foundation Centre, Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | | | - Matthew J. Hardman
- The Healing Foundation Centre, Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Ralf Paus
- Department of Dermatology, University of Luebeck, Luebeck, Germany
- The Dermatology Centre, Salford Royal NHS Foundation Trust and Institute of Inflammation and Repair, School of Translational Medicine, University of Manchester, Manchester, United Kingdom
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Costa R, Chen Y, Paredes R, Amaya E. Labeling primitive myeloid progenitor cells in Xenopus. Methods Mol Biol 2013; 916:141-55. [PMID: 22914938 DOI: 10.1007/978-1-61779-980-8_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
In Xenopus the first blood cells to differentiate in the embryo are the primitive myeloid lineages, which arise from the anterior ventral blood islands during the neurula stages. Primitive myeloid cells (PMCs) will give rise to the embryonic pool of neutrophils and macrophages, a highly migratory population of cells with various functions during development and tissue repair. Understanding the development and behavior of PMCs depends on our ability to label, manipulate, and image these cells. Xenopus embryos have several advantages in the study of PMCs, including a well-established fate map and the possibility of performing transplants in order to label these cells. In addition, Xenopus embryos are easy to manipulate and their external development and transparency at the tadpole stages make them amenable to imaging techniques. Here we describe two methods for labeling primitive myeloid progenitor cells during early Xenopus development.
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Affiliation(s)
- Ricardo Costa
- The Healing Foundation Centre, Faculty of Life Sciences, University of Manchester, Manchester, UK
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29
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Love NR, Chen Y, Ishibashi S, Kritsiligkou P, Lea R, Koh Y, Gallop JL, Dorey K, Amaya E. Amputation-induced reactive oxygen species are required for successful Xenopus tadpole tail regeneration. Nat Cell Biol 2013; 15:222-8. [PMID: 23314862 PMCID: PMC3728553 DOI: 10.1038/ncb2659] [Citation(s) in RCA: 351] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 11/26/2012] [Indexed: 12/22/2022]
Abstract
Understanding the molecular mechanisms that promote successful tissue regeneration is critical for continued advancements in regenerative medicine. Vertebrate amphibian tadpoles of the species Xenopus laevis and Xenopus tropicalis have remarkable abilities to regenerate their tails following amputation, through the coordinated activity of numerous growth factor signalling pathways, including the Wnt, Fgf, Bmp, Notch and TGF-β pathways. Little is known, however, about the events that act upstream of these signalling pathways following injury. Here, we show that Xenopus tadpole tail amputation induces a sustained production of reactive oxygen species (ROS) during tail regeneration. Lowering ROS levels, using pharmacological or genetic approaches, reduces the level of cell proliferation and impairs tail regeneration. Genetic rescue experiments restored both ROS production and the initiation of the regenerative response. Sustained increased ROS levels are required for Wnt/β-catenin signalling and the activation of one of its main downstream targets, fgf20 (ref. 7), which, in turn, is essential for proper tail regeneration. These findings demonstrate that injury-induced ROS production is an important regulator of tissue regeneration.
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Affiliation(s)
- Nick R Love
- Faculty of Life Sciences, University of Manchester, UK
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30
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Theveneau E, Mayor R. Can mesenchymal cells undergo collective cell migration? The case of the neural crest. Cell Adh Migr 2012; 5:490-8. [PMID: 22274714 DOI: 10.4161/cam.5.6.18623] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Cell migration is critical for proper development of the embryo and is also used by many cell types to perform their physiological function. For instance, cell migration is essential for immune cells to monitor the body and for epithelial cells to heal a wound whereas, in cancer cells, acquisition of migratory capabilities is a critical step towards malignancy. Migratory cells are often categorized into two groups: mesenchymal cells, produced by an epithelium-to-mesenchyme transition, that undergo solitary migration and epithelial-like cells which migrate collectively. However, on some occasions, mesenchymal cells may travel in large, dense groups and exhibit key features of collectively migrating cells such as coordination and cooperation. Here, using data published on Neural Crest cells, a highly invasive mesenchymal cell population that extensively migrate throughout the embryo, we explore the idea that other mesenchymal cells, including cancer cells, might be able to undergo collective cell migration under certain conditions and discuss how they could do so.
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Affiliation(s)
- Eric Theveneau
- Department of Cell and Developmental Biology, University College London, London, UK
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31
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Maéno M, Komiyama K, Matsuzaki Y, Hosoya J, Kurihara S, Sakata H, Izutsu Y. Distinct mechanisms control the timing of differentiation of two myeloid populations in Xenopus ventral blood islands. Dev Growth Differ 2012; 54:187-201. [PMID: 22470938 DOI: 10.1111/j.1440-169x.2011.01321.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Previous study has suggested that distinct populations of myeloid cells exist in the anterior ventral blood islands (aVBI) and posterior ventral blood islands (pVBI) in Xenopus neurula embryo. However, details for differentiation programs of these two populations have not been elucidated. In the present study, we examined the role of Wnt, vascular endothelial growth factor (VEGF) and fibroblast growth factor signals in the regulation of myeloid cell differentiation in the dorsal marginal zone and ventral marginal zone explants that are the sources of myeloid cells in the aVBI and pVBI. We found that regulation of Wnt activity is essential for the differentiation of myeloid cells in the aVBI but is not required for the differentiation of myeloid cells in the pVBI. Endogenous activity of the VEGF signal is necessary for differentiation of myeloid cells in the pVBI but is not involved in the differentiation of myeloid cells in the aVBI. Overall results reveal that distinct mechanisms are involved in the myeloid, erythroid and endothelial cell differentiation in the aVBI and pVBI.
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Affiliation(s)
- Mitsugu Maéno
- Department of Biology, Faculty of Science, Niigata University, 8050 Ikarashi-2, Nishi-ku, Niigata 950-2181, Japan.
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32
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Lea R, Bonev B, Dubaissi E, Vize PD, Papalopulu N. Multicolor fluorescent in situ mRNA hybridization (FISH) on whole mounts and sections. Methods Mol Biol 2012; 917:431-444. [PMID: 22956102 DOI: 10.1007/978-1-61779-992-1_24] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
In situ hybridization involves the hybridization of an antisense RNA probe to an mRNA transcript and it is a powerful method for the characterization of gene expression in tissues, organs, or whole organisms. Performed as a whole mount (WISH), it allows the detection of mRNA transcripts in three dimensions, while combined with sectioning, either before or after hybridization, it provides gene expression information with cellular resolution. FISH relies on the fluorescence detection of probes and is the method of choice for the simultaneous detection of transcripts with similar or overlapping expression patterns, as each can be clearly distinguished by the selection of fluorophore. Here, we describe a protocol for performing multicolor FISH in Xenopus embryos in whole mounts and sections that can be further combined with antibody staining.
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Affiliation(s)
- Robert Lea
- The Faculty of Life Sciences, University of Manchester, Manchester, England, UK
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33
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Carmona-Fontaine C, Theveneau E, Tzekou A, Tada M, Woods M, Page K, Parsons M, Lambris J, Mayor R. Complement fragment C3a controls mutual cell attraction during collective cell migration. Dev Cell 2011; 21:1026-37. [PMID: 22118769 PMCID: PMC3272547 DOI: 10.1016/j.devcel.2011.10.012] [Citation(s) in RCA: 224] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Revised: 10/03/2011] [Accepted: 10/14/2011] [Indexed: 12/16/2022]
Abstract
Collective cell migration is a mode of movement crucial for morphogenesis and cancer metastasis. However, little is known about how migratory cells coordinate collectively. Here we show that mutual cell-cell attraction (named here coattraction) is required to maintain cohesive clusters of migrating mesenchymal cells. Coattraction can counterbalance the natural tendency of cells to disperse via mechanisms such as contact inhibition and epithelial-to-mesenchymal transition. Neural crest cells are coattracted via the complement fragment C3a and its receptor C3aR, revealing an unexpected role of complement proteins in early vertebrate development. Loss of coattraction disrupts collective and coordinated movements of these cells. We propose that coattraction and contact inhibition act in concert to allow cell collectives to self-organize and respond efficiently to external signals, such as chemoattractants and repellents.
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Affiliation(s)
- Carlos Carmona-Fontaine
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Eric Theveneau
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Apostolia Tzekou
- Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104-6055, USA
| | - Masazumi Tada
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Mae Woods
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
- Department of Mathematics and CoMPLEX, University College London, Gower Street, London WC1E 6BT, UK
| | - Karen M. Page
- Department of Mathematics and CoMPLEX, University College London, Gower Street, London WC1E 6BT, UK
| | - Maddy Parsons
- Randall Division of Cell and Molecular Biophysics, King's College London, London WC2R 2LS, UK
| | - John D. Lambris
- Department of Pathology & Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104-6055, USA
| | - Roberto Mayor
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
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34
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Canning CA, Chan JSK, Common JEA, Lane EB, Jones CM. Developmental expression of the fermitin/kindlin gene family in Xenopus laevis embryos. Dev Dyn 2011; 240:1958-63. [PMID: 21761481 DOI: 10.1002/dvdy.22683] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Fermitin genes are highly conserved and encode cytocortex proteins that mediate integrin signalling. Fermitin 1 (Kindlin1) is implicated in Kindler syndrome, a human skin blistering disorder. We report the isolation of the three Fermitin orthologs from Xenopus laevis embryos and describe their developmental expression patterns. Fermitin 1 is expressed in the skin, otic and olfactory placodes, pharyngeal arches, pronephric duct, and heart. Fermitin 2 is restricted to the somites and neural crest. Fermitin 3 is expressed in the notochord, central nervous system, cement gland, ventral blood islands, vitelline veins, and myeloid cells. Our findings are consistent with the view that Fermitin 1 is generally expressed in the skin, Fermitin 2 in muscle, and Fermitin 3 in hematopoietic lineages. Moreover, we describe novel sites of Fermitin gene expression that extend our knowledge of this family. Our data provide a basis for further functional analysis of the Fermitin family in Xenopus laevis.
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35
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Love NR, Chen Y, Bonev B, Gilchrist MJ, Fairclough L, Lea R, Mohun TJ, Paredes R, Zeef LAH, Amaya E. Genome-wide analysis of gene expression during Xenopus tropicalis tadpole tail regeneration. BMC DEVELOPMENTAL BIOLOGY 2011; 11:70. [PMID: 22085734 PMCID: PMC3247858 DOI: 10.1186/1471-213x-11-70] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2011] [Accepted: 11/15/2011] [Indexed: 01/08/2023]
Abstract
Background The molecular mechanisms governing vertebrate appendage regeneration remain poorly understood. Uncovering these mechanisms may lead to novel therapies aimed at alleviating human disfigurement and visible loss of function following injury. Here, we explore tadpole tail regeneration in Xenopus tropicalis, a diploid frog with a sequenced genome. Results We found that, like the traditionally used Xenopus laevis, the Xenopus tropicalis tadpole has the capacity to regenerate its tail following amputation, including its spinal cord, muscle, and major blood vessels. We examined gene expression using the Xenopus tropicalis Affymetrix genome array during three phases of regeneration, uncovering more than 1,000 genes that are significantly modulated during tail regeneration. Target validation, using RT-qPCR followed by gene ontology (GO) analysis, revealed a dynamic regulation of genes involved in the inflammatory response, intracellular metabolism, and energy regulation. Meta-analyses of the array data and validation by RT-qPCR and in situ hybridization uncovered a subset of genes upregulated during the early and intermediate phases of regeneration that are involved in the generation of NADP/H, suggesting that these pathways may be important for proper tail regeneration. Conclusions The Xenopus tropicalis tadpole is a powerful model to elucidate the genetic mechanisms of vertebrate appendage regeneration. We have produced a novel and substantial microarray data set examining gene expression during vertebrate appendage regeneration.
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Affiliation(s)
- Nick R Love
- Faculty of Life Sciences, University of Manchester, UK
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36
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Robert J, Cohen N. The genus Xenopus as a multispecies model for evolutionary and comparative immunobiology of the 21st century. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2011; 35:916-923. [PMID: 21277325 PMCID: PMC3109137 DOI: 10.1016/j.dci.2011.01.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The Xenopus model for immunological research offers a collection of invaluable research tools including MHC-defined clones, inbred strains, cell lines, and monoclonal antibodies. Further, the annotated full genome sequence of Xenopus tropicalis and its remarkable conservation of gene organization with mammals, as well as ongoing genome mapping and mutagenesis studies in X. tropicalis, add a new dimension to the study of immunity. In this paper, we review uses of this amphibian model to study: the development of the immune system; vascular and lymphatic regeneration; immune tolerance; tumor immunity; immune responses to important emerging infectious diseases; and the evolution of classical and non-classical MHC class I genes. We also discuss the rich potential of the species with different degrees of polypoidy resulting from whole genome-wide duplication of the Xenopodinae subfamily as a model to study regulation at the genome level.
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Affiliation(s)
- Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, United States.
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37
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Deimling SJ, Drysdale TA. Fgf is required to regulate anterior-posterior patterning in the Xenopus lateral plate mesoderm. Mech Dev 2011; 128:327-41. [PMID: 21763769 DOI: 10.1016/j.mod.2011.06.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2011] [Revised: 06/21/2011] [Accepted: 06/23/2011] [Indexed: 11/26/2022]
Abstract
Given that the lateral plate mesoderm (LPM) gives rise to the cardiovascular system, identifying the cascade of signalling events that subdivides the LPM into distinct regions during development is an important question. Retinoic acid (RA) is known to be necessary for establishing the expression boundaries of important transcription factors that demarcate distinct regions along the anterior posterior axis of the LPM. Here, we demonstrate that fibroblast growth factor (Fgf) signalling is also necessary for regulating the expression domains of the same transcription factors (nkx2.5, foxf1, hand1 and sall3) by restricting the RA responsive LPM domains. When Fgf signalling is inhibited in neurula stage embryos, the more posterior LPM expression domains are lost, while the more anterior domains are extended further posterior. The domain changes are maintained throughout development as Fgf inhibition results in similar domain changes in late stage embryos. We also demonstrate that Fgf signalling is necessary for both the initiation of heart specification, and for maintaining heart specification until overt differentiation occurs. Fgf signalling is also necessary to restrict vascular patterning and create a vascular free domain in the posterior end of the LPM that correlates with the expression of hand1. Finally, we show cross talk between the RA and Fgf signalling pathways in the patterning of the LPM. We suggest that this tissue wide patterning event, active during the neurula stage, is an initial step in regional specification of the LPM, and this process is an essential early event in LPM patterning.
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Affiliation(s)
- Steven J Deimling
- Children's Health Research Institute, 800 Commissioners Road E., London, Ontario, Canada
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38
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Smith SJ, Mohun TJ. Early cardiac morphogenesis defects caused by loss of embryonic macrophage function in Xenopus. Mech Dev 2011; 128:303-15. [PMID: 21515365 PMCID: PMC3157588 DOI: 10.1016/j.mod.2011.04.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2010] [Revised: 04/06/2011] [Accepted: 04/07/2011] [Indexed: 11/26/2022]
Abstract
The heart-forming mesoderm in Xenopus embryos lies adjacent to the source of the first embryonic population of macrophages. Such macrophages underlie the bilateral myocardial cell layers as they converge to form a linear heart tube. We have examined whether such macrophages participate in early cardiac morphogenesis, combining morpholino oligonucleotides that inhibit macrophage differentiation or function with transgenic reporters to assess macrophage numbers in living embryos. We show that loss of macrophage production through tadpole stages of development by morpholino-mediated knockdown of the spib transcription factor results in an arrest of heart formation. The myocardium fails to form the fused, wedge-shaped trough that precedes heart tube formation and in the most severe cases, myocardial differentiation is also impaired. Knockdown of the Ly6 protein lurp1, an early, secreted product from differentiated macrophages, produces a similar arrest to myocardial morphogenesis. Heart development can moreover be rescued by surgical-transfer of normal macrophage domains into morpholino-injected embryos. Together, these results demonstrate that amphibian heart formation depends on the presence and activity of the macrophage population, indicating that these cells may be an important source of growth cues necessary for early cardiac morphogenesis.
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Affiliation(s)
- Stuart J Smith
- Division of Developmental Biology, MRC-National Institute for Medical Research, The Ridgeway, Mill Hill, London, UK
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Panagiotaki N, Dajas-Bailador F, Amaya E, Papalopulu N, Dorey K. Characterisation of a new regulator of BDNF signalling, Sprouty3, involved in axonal morphogenesis in vivo. Development 2010; 137:4005-15. [PMID: 21062861 DOI: 10.1242/dev.053173] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
During development, many organs, including the kidney, lung and mammary gland, need to branch in a regulated manner to be functional. Multicellular branching involves changes in cell shape, proliferation and migration. Axonal branching, however, is a unicellular process that is mediated by changes in cell shape alone and as such appears very different to multicellular branching. Sprouty (Spry) family members are well-characterised negative regulators of Receptor tyrosine kinase (RTK) signalling. Knockout of Spry1, 2 and 4 in mouse result in branching defects in different organs, indicating an important role of RTK signalling in controlling branching pattern. We report here that Spry3, a previously uncharacterised member of the Spry family plays a role in axonal branching. We found that spry3 is expressed specifically in the trigeminal nerve and in spinal motor and sensory neurons in a Brain-derived neurotrophin factor (BDNF)-dependent manner. Knockdown of Spry3 expression causes an excess of axonal branching in spinal cord motoneurons in vivo. Furthermore, Spry3 inhibits the ability of BDNF to induce filopodia in Xenopus spinal cord neurons. Biochemically, we show that Spry3 represses calcium release downstream of BDNF signalling. Altogether, we have found that Spry3 plays an important role in the regulation of axonal branching of motoneurons in vivo, raising the possibility of unexpected conservation in the involvement of intracellular regulators of RTK signalling in multicellular and unicellular branching.
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Affiliation(s)
- Niki Panagiotaki
- Faculty of Life Sciences, Michael Smith Building, University of Manchester, Oxford Road, Manchester, UK
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40
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Keeping in touch with contact inhibition of locomotion. Trends Cell Biol 2010; 20:319-28. [PMID: 20399659 PMCID: PMC2927909 DOI: 10.1016/j.tcb.2010.03.005] [Citation(s) in RCA: 201] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Revised: 03/24/2010] [Accepted: 03/24/2010] [Indexed: 01/01/2023]
Abstract
Contact inhibition of locomotion (CIL) is the process by which cells in vitro change their direction of migration upon contact with another cell. Here, we revisit the concept that CIL plays a central role in the migration of single cells and in collective migration, during both health and disease. Importantly, malignant cells exhibit a diminished CIL behaviour which allows them to invade healthy tissues. Accumulating evidence indicates that CIL occurs in vivo and that regulation of small Rho GTPases is important in the collapse of cell protrusions upon cell contact, the first step of CIL. Finally, we propose possible cell surface proteins that could be involved in the initial contact that regulates Rho GTPases during CIL.
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41
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Salanga MC, Meadows SM, Myers CT, Krieg PA. ETS family protein ETV2 is required for initiation of the endothelial lineage but not the hematopoietic lineage in the Xenopus embryo. Dev Dyn 2010; 239:1178-87. [PMID: 20235229 DOI: 10.1002/dvdy.22277] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Transcription factors of the ETS family are important regulators of endothelial and hematopoietic development. We have characterized the Xenopus orthologue of the ETS transcription factor, ETV2. Expression analysis shows that etv2 is highly expressed in hematopoietic and endothelial precursor cells in the Xenopus embryo. In gain-of-function experiments, ETV2 is sufficient to activate ectopic expression of vascular endothelial markers. In addition, ETV2 activated expression of hematopoietic genes representing the myeloid but not the erythroid lineage. Loss-of-function studies indicate that ETV2 is required for expression of all endothelial markers examined. However, knockdown of ETV2 has no detectable effects on expression of either myeloid or erythroid markers. This contrasts with studies in mouse and zebrafish where ETV2 is required for development of the myeloid lineage. Our studies confirm an essential role for ETV2 in endothelial development, but also reveal important differences in hematopoietic development between organisms.
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Affiliation(s)
- Matthew C Salanga
- Department of Cell Biology and Anatomy, Molecular Cardiovascular Research Program, University of Arizona, Tucson, Arizona 85724, USA
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42
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Chen Y, Costa RMB, Love NR, Soto X, Roth M, Paredes R, Amaya E. C/EBPalpha initiates primitive myelopoiesis in pluripotent embryonic cells. Blood 2009; 114:40-8. [PMID: 19420355 PMCID: PMC3747498 DOI: 10.1182/blood-2008-11-189159] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The molecular mechanisms that underlie the development of primitive myeloid cells in vertebrate embryos are not well understood. Here we characterize the role of cebpa during primitive myeloid cell development in Xenopus. We show that cebpa is one of the first known hematopoietic genes expressed in the embryo. Loss- and gain-of-function studies show that it is both necessary and sufficient for the development of functional myeloid cells. In addition, we show that cebpa misexpression leads to the precocious induction of myeloid cell markers in pluripotent prospective ectodermal cells, without the cells transitioning through a general mesodermal state. Finally, we use live imaging to show that cebpa-expressing cells exhibit many attributes of terminally differentiated myeloid cells, such as highly active migratory behavior, the ability to quickly and efficiently migrate toward wounds and phagocytose bacteria, and the ability to enter the circulation. Thus, C/EPBalpha is the first known single factor capable of initiating an entire myelopoiesis pathway in pluripotent cells in the embryo.
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Affiliation(s)
- Yaoyao Chen
- The Healing Foundation Centre, Michael Smith Building, Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
| | - Ricardo M. B. Costa
- The Healing Foundation Centre, Michael Smith Building, Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
| | - Nick R. Love
- The Healing Foundation Centre, Michael Smith Building, Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
| | - Ximena Soto
- The Healing Foundation Centre, Michael Smith Building, Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
| | - Martin Roth
- The Healing Foundation Centre, Michael Smith Building, Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
| | - Roberto Paredes
- The Healing Foundation Centre, Michael Smith Building, Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
| | - Enrique Amaya
- The Healing Foundation Centre, Michael Smith Building, Faculty of Life Sciences, University of Manchester, Oxford Road, Manchester, M13 9PT, United Kingdom
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43
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Abstract
Xenopus laevis is the model of choice for evolutionary, comparative, and developmental studies of immunity, and invaluable research tools including MHC-defined clones, inbred strains, cell lines, and monoclonal antibodies are available for these studies. Recent efforts to use Silurana (Xenopus) tropicalis for genetic analyses have led to the sequencing of the whole genome. Ongoing genome mapping and mutagenesis studies will provide a new dimension to the study of immunity. Here we review what is known about the immune system of X. laevis integrated with available genomic information from S. tropicalis. This review provides compelling evidence for the high degree of similarity and evolutionary conservation between Xenopus and mammalian immune systems. We propose to build a powerful and innovative comparative biomedical model based on modern genetic technologies that takes take advantage of X. laevis and S. tropicalis, as well as the whole Xenopus genus. Developmental Dynamics 238:1249-1270, 2009. (c) 2009 Wiley-Liss, Inc.
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Affiliation(s)
- Jacques Robert
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, USA.
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