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Yang Z, Chen S, Ying H, Yao W. Targeting syndecan-1: new opportunities in cancer therapy. Am J Physiol Cell Physiol 2022; 323:C29-C45. [PMID: 35584326 PMCID: PMC9236862 DOI: 10.1152/ajpcell.00024.2022] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 05/16/2022] [Accepted: 05/16/2022] [Indexed: 12/02/2022]
Abstract
Syndecan-1 (SDC1, CD138) is one of the heparan sulfate proteoglycans and is essential for maintaining normal cell morphology, interacting with the extracellular and intracellular protein repertoire, as well as mediating signaling transduction upon environmental stimuli. The critical role of SDC1 in promoting tumorigenesis and metastasis has been increasingly recognized in various cancer types, implying a promising potential of utilizing SDC1 as a novel target for cancer therapy. This review summarizes the current knowledge on SDC1 structure and functions, including its role in tumor biology. We also discuss the highlights and limitations of current SDC1-targeted therapies as well as the obstacles in developing new therapeutic methods, offering our perspective on the future directions to target SDC1 for cancer treatment.
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Affiliation(s)
- Zecheng Yang
- Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- UTHealth Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Shuaitong Chen
- Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
- UTHealth Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Haoqiang Ying
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Wantong Yao
- Department of Translational Molecular Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas
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Velleman SG, Coy CS. Research Note: Effect of selection for body weight on the adipogenic conversion of turkey myogenic satellite cells by Syndecan-4 and its covalently attached N-glycosylation chains. Poult Sci 2020; 99:1209-1215. [PMID: 32029150 PMCID: PMC7587650 DOI: 10.1016/j.psj.2019.12.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 10/01/2019] [Indexed: 11/26/2022] Open
Abstract
Adult myoblasts, satellite cells, will proliferate, and differentiate into myotubes in vitro. However, changes in environmental and nutritional conditions will result in the satellite cells differentiating into adipocyte-like cells synthesizing lipids. Prior research has shown that levels of N-glycosylation and heparan sulfate can promote or prevent the adipogenic conversion of myogenic satellite cells. Syndecan-4, an N-glycosylated heparan sulfate proteoglycan, has been shown to play key roles in satellite cell proliferation and migration. The objective of the current study was to determine if syndecan-4, and syndecan-4 N-glycosylation and heparan sulfate chain levels altered the conversion of satellite cells to an adipogenic cell fate and if growth selection affected the response of the satellite cells. Over-expression of syndecan-4, syndecan-4 without N-glycosylated chains but with its heparan sulfate chains attached, syndecan-4 without heparan sulfate chains with its N-glycosylation chains, and syndecan-4 without N-glycosylation and heparan sulfate chains was measured for lipid accumulation in pectoralis major muscle satellite cells isolated from the Randombred Control line 2 (RBC2) and 16 wk body weight (F line) turkeys. The F line was selected from the RBC2 line for only 16 wk body weight. Results from this study demonstrated that wild type levels of syndecan-4 and its covalently attached N-glycosylation chains play a key role in regulating the conversion of pectoralis major muscle satellite cells to an adipogenic lineage while selection for body weight was not a major contributing factor in this conversion.
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Affiliation(s)
- Sandra G Velleman
- The Ohio State University/Ohio Agricultural Research and Development Center, 1680 Madison Ave, Wooster OH 44691, USA.
| | - Cynthia S Coy
- The Ohio State University/Ohio Agricultural Research and Development Center, 1680 Madison Ave, Wooster OH 44691, USA
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Jang B, Jung H, Hong H, Oh ES. Syndecan transmembrane domain modulates intracellular signaling by regulating the oligomeric status of the cytoplasmic domain. Cell Signal 2018; 52:121-126. [PMID: 30195038 DOI: 10.1016/j.cellsig.2018.09.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 09/04/2018] [Accepted: 09/04/2018] [Indexed: 11/19/2022]
Abstract
Cell surface receptors must specifically recognize an extracellular ligand and then trigger an appropriate response within the cell. Their general structure enables this, as it comprises an extracellular domain that can bind an extracellular ligand, a cytoplasmic domain that can transduce a signal inside the cell to produce an appropriate response, and a transmembrane domain that links the two and is responsible for accurately delivering specific information on a binding event from the extracellular domain to the cytoplasmic domain, to trigger the proper response. A vast body of research has focused on elucidating the specific mechanisms responsible for regulating extracellular binding events and the subsequent interactions of the cytoplasmic domain with intracellular signaling. In contrast, far less work has focused on examining how the transmembrane domain links these domains and delivers the necessary information. In this review, we propose the importance of the transmembrane domain as a signal regulator. We highlight the cell adhesion receptor, syndecan, as a special case, and propose that the transmembrane domain-mediated oligomerization of the syndecan cytoplasmic domain is a unique regulatory mechanism in syndecan signaling.
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Affiliation(s)
- Bohee Jang
- Department of Life Sciences, The Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Hyejung Jung
- Skin QC Institute of Dermatological Sciences, Seoul, 03759, Republic of Korea
| | - Heejeong Hong
- Department of Life Sciences, The Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea
| | - Eok-Soo Oh
- Department of Life Sciences, The Research Center for Cellular Homeostasis, Ewha Womans University, Seoul 120-750, Republic of Korea; Skin QC Institute of Dermatological Sciences, Seoul, 03759, Republic of Korea.
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Velleman SG, Song Y. Development and Growth of the Avian Pectoralis Major (Breast) Muscle: Function of Syndecan-4 and Glypican-1 in Adult Myoblast Proliferation and Differentiation. Front Physiol 2017; 8:577. [PMID: 28848451 PMCID: PMC5550705 DOI: 10.3389/fphys.2017.00577] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 07/25/2017] [Indexed: 12/19/2022] Open
Abstract
Muscle fiber number is determined around the time hatch with continued posthatch muscle growth being mediated by the adult myoblast, satellite cell, population of cells. Satellite cells are dynamic in their expression of proteins including the cell membrane associated proteoglycans, syndecan-4 and glypican-1. These proteoglycans play roles in organizing the extracellular environment in the satellite cell niche, cytoskeletal structure, cell-to-cell adhesion, satellite cell migration, and signal transduction. This review article focuses on syndecan-4 and glypican-1 as both are capable of regulating satellite cell responsiveness to fibroblast growth factor 2. Fibroblast growth factor 2 is a potent stimulator of muscle cell proliferation and a strong inhibitor of differentiation. Proteoglycans are composed of a central core protein defined functional domains, and covalently attached glycosaminoglycans and N-glycosylation chains. The functional association of these components with satellite cell function is discussed as well as an emerging role for microRNA regulation of syndecan-4 and glypican-1.
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Affiliation(s)
- Sandra G Velleman
- Department of Animal Sciences, The Ohio State UniversityWooster, OH, United States
| | - Yan Song
- Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical SchoolBoston, MA, United States
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Powell D, Velleman S, Cowieson A, Singh M, Muir W. Influence of chick hatch time and access to feed on broiler muscle development. Poult Sci 2016; 95:1433-48. [DOI: 10.3382/ps/pew047] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 01/10/2016] [Indexed: 11/20/2022] Open
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Dodson MV, Allen RE, Du M, Bergen WG, Velleman SG, Poulos SP, Fernyhough-Culver M, Wheeler MB, Duckett SK, Young MRI, Voy BH, Jiang Z, Hausman GJ. INVITED REVIEW: Evolution of meat animal growth research during the past 50 years: Adipose and muscle stem cells. J Anim Sci 2016; 93:457-81. [PMID: 26020737 DOI: 10.2527/jas.2014-8221] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
If one were to compare today's animal growth research to research from a mere 50 yr ago, one would see programs with few similarities. The evolution of this research from whole-animal through cell-based and finally molecular and genomic studies has been enhanced by the identification, isolation, and in vitro evaluation of adipose- and muscle-derived stem cells. This paper will highlight the struggles and the milestones that make this evolving area of research what it is today. The contribution of adipose and muscle stem cell research to development and growth, tissue regeneration, and final carcass composition are reviewed.
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Harding RL, Velleman SG. MicroRNA regulation of myogenic satellite cell proliferation and differentiation. Mol Cell Biochem 2015; 412:181-95. [PMID: 26715133 DOI: 10.1007/s11010-015-2625-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 12/08/2015] [Indexed: 01/10/2023]
Abstract
Myogenic satellite cells are stem cells responsible for muscle growth and regeneration. MicroRNAs (miRNAs) play significant roles in regulating numerous cellular processes. Two genes essential to satellite cell function are syndecan-4 and glypican-1. To determine if miRNAs influence myogenic satellite cell function, one miRNA predicted to bind syndecan-4 (miR-128) and two predicted to bind glypican-1 (miR-24 and miR-16) were inhibited in vitro by transfection of inhibitors targeting each miRNA. Inhibition of these miRNAs differentially affected the expression of syndecan-4, glypican-1, and myogenic regulatory factors myoD and myogenin. Inhibition of miR-16 reduced proliferation of satellite cells at 72 h. Inhibition of miR-128 and miR-24 did not affect proliferation. Inhibition of miRNAs reduced differentiation of satellite cells into myotubes at 48 and 72 h except for miR-16, which only affected differentiation at 72 h. Inhibition of all three miRNAs decreased myotube width at 24 h of differentiation and increased myotube width at 48 h of differentiation. Inhibiting these miRNAs also increased the number of nuclei per myotube at 72 h of differentiation. These data demonstrate individual miRNAs regulate genes essential for myogenic satellite cell proliferation and differentiation.
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Affiliation(s)
- Rachel L Harding
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, 1680 Madison Ave., Wooster, OH, 44691, USA
| | - Sandra G Velleman
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, 1680 Madison Ave., Wooster, OH, 44691, USA.
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Rønning SB, Carlson CR, Stang E, Kolset SO, Hollung K, Pedersen ME. Syndecan-4 Regulates Muscle Differentiation and Is Internalized from the Plasma Membrane during Myogenesis. PLoS One 2015; 10:e0129288. [PMID: 26068620 PMCID: PMC4467083 DOI: 10.1371/journal.pone.0129288] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 05/06/2015] [Indexed: 12/31/2022] Open
Abstract
The cell surface proteoglycan syndecan-4 has been reported to be crucial for muscle differentiation, but the molecular mechanisms still remain to be fully understood. During in vitro differentiation of bovine muscle cells immunocytochemical analyses showed strong labelling of syndecan-4 intracellularly, in close proximity with Golgi structures, in membranes of intracellular vesicles and finally, in the nuclear area including the nuclear envelope. Chase experiments showed that syndecan-4 was internalized from the plasma membrane during this process. Furthermore, when syndecan-4 was knocked down by siRNA more myotubes were formed, and the expression of myogenic transcription factors, β1-integrin and actin was influenced. However, when bovine muscle cells were treated with a cell-penetrating peptide containing the cytoplasmic region of syndecan-4, myoblast fusion and thus myotube formation was blocked, both in normal cells and in syndecan-4 knock down cells. Altogether this suggests that the cytoplasmic domain of syndecan-4 is important in regulation of myogenesis. The internalization of syndecan-4 from the plasma membrane during muscle differentiation and the nuclear localization of syndecan-4 in differentiated muscle cells may be part of this regulation, and is a novel aspect of syndecan biology which merits further studies.
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Affiliation(s)
| | - Cathrine R. Carlson
- Institute for Experimental Medical Research, Oslo University Hospital and University of Oslo, Oslo, Norway
- KG Jebsen Cardiac Research Center and Center for Heart Failure Research, University of Oslo, Oslo, Norway
| | - Espen Stang
- Department of Pathology, Oslo University Hospital, Rikshospitalet, P.O. Box 4950 Nydalen, 0424 Oslo, Norway
| | - Svein O. Kolset
- Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
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Powell D, McFarland D, Cowieson A, Muir W, Velleman S. The effect of nutritional status on myogenic gene expression of satellite cells derived from different muscle types. Poult Sci 2014; 93:2278-88. [DOI: 10.3382/ps.2013-03810] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Song J, Kim JS, Choi SS, Kim Y. Structural Effects of the GXXXG Motif on the Oligomer Formation of Transmembrane Domain of Syndecan-4. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.12.3577] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Shin J, McFarland DC, Strasburg GM, Velleman SG. Function of death-associated protein 1 in proliferation, differentiation, and apoptosis of chicken satellite cells. Muscle Nerve 2013; 48:777-90. [PMID: 23483580 DOI: 10.1002/mus.23832] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/27/2013] [Indexed: 11/09/2022]
Abstract
INTRODUCTION Muscle growth and regeneration are processes closely associated with proliferation, differentiation, and apoptosis of muscle cells. Death-associated protein 1 (DAP1) has been identified as a negative regulator of autophagy. Little is known about the function of DAP1 in the regulation of myogenesis and satellite cells. METHODS Chicken satellite cells were transfected with DAP1 cloned into the pCMS-enhanced green fluorescent protein vector or pcDNA3.1 vector, or a small interference RNA against the endogenous DAP1 gene. The cells were assayed for proliferation, differentiation, and apoptosis. RESULTS The overexpression of DAP1 increased proliferation, differentiation, and myotube diameter, but it had no effect on satellite cell apoptosis. In contrast, knockdown of DAP1 significantly decreased proliferation, differentiation, and number of nuclei per myotube, and it increased apoptosis of the cells. CONCLUSION DAP1 is required for regulating myogenesis and apoptosis of satellite cells, which may affect muscle mass accretion and regeneration, and ameliorate muscle sarcopenia.
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Affiliation(s)
- Jonghyun Shin
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, 213 Gerlaugh Hall, 1680 Madison Avenue, Ohio State University, Wooster, Ohio, 44691, USA
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The effect of syndecan-4 and glypican-1 expression on age-related changes in myogenic satellite cell proliferation, differentiation, and fibroblast growth factor 2 responsiveness. Comp Biochem Physiol A Mol Integr Physiol 2013; 166:590-602. [PMID: 24036479 DOI: 10.1016/j.cbpa.2013.09.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 09/07/2013] [Accepted: 09/09/2013] [Indexed: 11/22/2022]
Abstract
Satellite cells are multipotential stem cells responsible for muscle growth and regeneration. Satellite cell proliferation, differentiation, and responsiveness to fibroblast growth factor 2 (FGF2) is, in part, regulated by the heparan sulfate proteoglycans syndecan-4 and glypican-1. Syndecan-4 and glypican-1 expression declines with satellite cell age and may be associated with decreased satellite cell activity. The objective of the current study was to determine if overexpression of syndecan-4 and glypican-1 would increase proliferation, differentiation and FGF2 responsiveness in satellite cells isolated from pectoralis major muscle from 16-wk-old turkeys. Overexpression of syndecan-4 and glypican-1 did not have a significant effect on proliferation and differentiation in 1d, 7 wk, and 16 wk satellite cells, and did not affect FGF2 responsiveness during proliferation. Expression of syndecan-4 and glypican-1 increased differentiation at 48 h in 1d, 7 wk, and 16 wk cells treated with FGF2. Expression of myogenic regulatory factors MyoD, myogenin, and MRF4 was affected by the overexpression of syndecan-4 and glypican-1. However, changes in myogenic regulatory factor expression did not have a significant effect on proliferation or differentiation. These data demonstrate that syndecan-4 and glypican-1 are likely not directly associated with the age related decrease in satellite cell activity.
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Harthan LB, McFarland DC, Velleman SG. Changes in proliferation, differentiation, fibroblast growth factor 2 responsiveness and expression of syndecan-4 and glypican-1 with turkey satellite cell age. Dev Growth Differ 2013; 55:622-34. [DOI: 10.1111/dgd.12069] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 05/10/2013] [Accepted: 05/14/2013] [Indexed: 11/30/2022]
Affiliation(s)
- Laura B. Harthan
- Department of Animal Sciences; Ohio Agricultural Research and Development Center; The Ohio State University; Wooster; Ohio; USA
| | - Douglas C. McFarland
- Department of Animal Science; South Dakota State University; Brookings; South Dakota; USA
| | - Sandra G. Velleman
- Department of Animal Sciences; Ohio Agricultural Research and Development Center; The Ohio State University; Wooster; Ohio; USA
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Choi SS, Kim JS, Song J, Kim Y. High-yield Expression and Characterization of Syndecan-4 Extracellular, Transmembrane and Cytoplasmic Domains. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.4.1120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Shin J, McFarland DC, Velleman SG. Migration of turkey muscle satellite cells is enhanced by the syndecan-4 cytoplasmic domain through the activation of RhoA. Mol Cell Biochem 2012; 375:115-30. [PMID: 23212449 DOI: 10.1007/s11010-012-1534-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Accepted: 11/23/2012] [Indexed: 01/12/2023]
Abstract
Syndecan-4 (S4) is a cell membrane-associated heparan sulfate proteoglycan that forms oligomers in muscle satellite cells. The S4 oligomers activate protein kinase Cα (PKCα) through the S4 cytoplasmic domain and may regulate the activation of ras homolog gene family member A (RhoA), a signal transduction molecule down-stream of PKCα which is thought to influence cell migration. However, little is known about the function of the S4 cytoplasmic domain in satellite cell migration and RhoA activation. The objective of the current study was to determine the function of S4 and its cytoplasmic domain in cell migration and RhoA activation. To study the objective, clones of S4 and S4 without the cytoplasmic domain (S4C) were used in overexpression studies, and small interference RNAs targeting S4 or RhoA were used in knockdown studies. Satellite cell migration was increased by S4 overexpression, but decreased by the knockdown or deletion of the S4 cytoplasmic domain. The RhoA protein was activated by the overexpression of S4, but not with the deletion of the S4 cytoplasmic domain. The treatment of Rho activator II or the knockdown of RhoA also modulated satellite cell migration. Finally, co-transfection (S4 overexpression and RhoA knockdown) and rescue (the knockdown of S4 and the treatment with Rho activator II) studies demonstrated that S4-mediated satellite cell migration was regulated through the activation of RhoA. The cytoplasmic domain of S4 is required for cell migration and RhoA activation which will affect muscle fiber formation.
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Affiliation(s)
- Jonghyun Shin
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, 213 Gerlaugh Hall, 1680 Madison Avenue, Wooster, OH 44691, USA
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Shanmugasundaram R, Selvaraj RK. Regulatory T cell properties of thymic CD4+CD25+ cells in ducks. Vet Immunol Immunopathol 2012; 149:20-7. [PMID: 22717168 DOI: 10.1016/j.vetimm.2012.05.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2011] [Revised: 04/12/2012] [Accepted: 05/22/2012] [Indexed: 12/21/2022]
Abstract
Thymic CD4(+)CD25(+) cells from ducks were characterized for mammalian T regulatory cells' suppressive and cytokine production properties. The cross reactivity of anti-chicken CD25 monoclonal antibody with duck CD25 was confirmed by evaluating Concanavalin-A-stimulated CD25 upregulation in splenocytes. CD4(+)CD25(+) cells were detectable in the thymus, spleen, cecal tonsil, and lung (airsacs), but not in the bursa. Duck CD4(+)CD25(+) cells had approximately nine-fold higher IL-10 mRNA, 12-fold higher TGF-β, 16-fold higher CTLA-4, and nine-fold higher LAG-3 mRNA amounts than thymic CD4(+)CD25(-) cells. Thymic CD4(+)CD25(+) cells had no detectable levels of IL-2 mRNA. Duck CD4(+)CD25(+) cells had a three-fold higher IL-10 mRNA amount than chicken CD4(+)CD25(+) cells. Duck CD4(+)CD25(+) cells were anergic in vitro. Duck CD4(+)CD25(+) cells suppressed naive cell proliferation at effector: responder cell ratios above 0.5:1 in both contact-dependent and -independent pathways. It could be concluded that thymic CD4(+)CD25(+) cells in ducks are most likely the counterpart of mammalian T regulatory cells.
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Affiliation(s)
- Revathi Shanmugasundaram
- Department of Animal Sciences, Ohio Agricultural Research and Development Center, Wooster, OH 44691, USA
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