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Ma Z, Wu Y, Zhang Y, Zhang W, Jiang M, Shen X, Wu H, Chen X, Di G. Morphologic, cytometric, quantitative transcriptomic and functional characterisation provide insights into the haemocyte immune responses of Pacific abalone ( Haliotis discus hannai). Front Immunol 2024; 15:1376911. [PMID: 39015569 PMCID: PMC11250055 DOI: 10.3389/fimmu.2024.1376911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 05/31/2024] [Indexed: 07/18/2024] Open
Abstract
In recent years, the abalone aquaculture industry has been threatened by the bacterial pathogens. The immune responses mechanisms underlying the phagocytosis of haemocytes remain unclear in Haliotis discus hannai. It is necessary to investigate the immune mechanism in response to these bacterial pathogens challenges. In this study, the phagocytic activities of haemocytes in H. discus hannai were examined by flow cytometry combined with electron microscopy and transcriptomic analyses. The results of Vibrio parahaemolyticus, Vibrio alginolyticus and Staphylococcus aureu challenge using electron microscopy showed a process during phagosome formation in haemocytes. The phagocytic rate (PP) of S. aureus was higher than the other five foreign particles, which was about 63%. The PP of Vibrio harveyi was about 43%, the PP peak of V. alginolyticus in haemocyte was 63.7% at 1.5 h. After V. parahaemolyticus and V. alginolyticus challenge, acid phosphatase, alkaline phosphatase, total superoxide dismutase, lysozyme, total antioxidant capacity, catalase, nitric oxide synthase and glutathione peroxidase activities in haemocytes were measured at different times, differentially expressed genes (DEGs) were identified by quantitative transcriptomic analysis. The identified DEGs after V. parahaemolyticus challenge included haemagglutinin/amebocyte aggregation factor-like, supervillin-like isoform X4, calmodulin-like and kyphoscoliosis peptidase-like; the identified DEGs after V. alginolyticus challenge included interleukin-6 receptor subunit beta-like, protein turtle homolog B-like, rho GTPase-activating protein 6-like isoform X2, leukocyte surface antigen CD53-like, calponin-1-like, calmodulin-like, troponin C, troponin I-like isoform X4, troponin T-like isoform X18, tumor necrosis factor ligand superfamily member 10-like, rho-related protein racA-like and haemagglutinin/amebocyte aggregation factor-like. Some immune-related KEGG pathways were significantly up-regulated or down-regulated after challenge, including thyroid hormone synthesis, Th17 cell differentiation signalling pathway, focal adhesion, melanogenesis, leukocyte transendothelial migration, inflammatory mediator regulation of TRP channels, ras signalling pathway, rap1 signalling pathway. This study is the first step towards understanding the H. discus hannai immune system by adapting several tools to gastropods and providing a first detailed morpho-functional study of their haemocytes.
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Affiliation(s)
- Zeyuan Ma
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yunlong Wu
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Yu Zhang
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Weini Zhang
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Mingmei Jiang
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xiaoyue Shen
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Hailian Wu
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| | - Xinhua Chen
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Guilan Di
- State Key Laboratory of Mariculture Breeding, Key Laboratory of Marine Biotechnology of Fujian Province, Institute of Oceanology, College of Marine Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
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Ramoni D, Tirandi A, Montecucco F, Liberale L. Sepsis in elderly patients: the role of neutrophils in pathophysiology and therapy. Intern Emerg Med 2024; 19:901-917. [PMID: 38294676 PMCID: PMC11186952 DOI: 10.1007/s11739-023-03515-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 12/17/2023] [Indexed: 02/01/2024]
Abstract
Sepsis is among the most important causes of mortality, particularly within the elderly population. Sepsis prevalence is on the rise due to different factors, including increasing average population age and the concomitant rise in the prevalence of frailty and chronic morbidities. Recent investigations have unveiled a "trimodal" trajectory for sepsis-related mortality, with the ultimate zenith occurring from 60 to 90 days until several years after the original insult. This prolonged temporal course ostensibly emanates from the sustained perturbation of immune responses, persevering beyond the phase of clinical convalescence. This phenomenon is particularly associated with the aging immune system, characterized by a broad dysregulation commonly known as "inflammaging." Inflammaging associates with a chronic low-grade activation of the innate immune system preventing an appropriate response to infective agents. Notably, during the initial phases of sepsis, neutrophils-essential in combating pathogens-may exhibit compromised activity. Paradoxically, an overly zealous neutrophilic reaction has been observed to underlie multi-organ dysfunction during the later stages of sepsis. Given this scenario, discovering treatments that can enhance neutrophil activity during the early phases of sepsis while curbing their overactivity in the later phases could prove beneficial in fighting pathogens and reducing the detrimental effects caused by an overactive immune system. This narrative review delves into the potential key role of neutrophils in the pathological process of sepsis, focusing on how the aging process impacts their functions, and highlighting possible targets for developing immune-modulatory therapies. Additionally, the review includes tables that outline the principal potential targets for immunomodulating agents.
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Affiliation(s)
- Davide Ramoni
- First Clinic of Internal Medicine, Department of Internal Medicine, University of Genoa, 6 Viale Benedetto XV, 16132, Genoa, Italy
| | - Amedeo Tirandi
- First Clinic of Internal Medicine, Department of Internal Medicine, University of Genoa, 6 Viale Benedetto XV, 16132, Genoa, Italy
| | - Fabrizio Montecucco
- First Clinic of Internal Medicine, Department of Internal Medicine, University of Genoa, 6 Viale Benedetto XV, 16132, Genoa, Italy
- IRCCS Ospedale Policlinico San Martino Genoa-Italian Cardiovascular Network, Genoa, Italy
| | - Luca Liberale
- First Clinic of Internal Medicine, Department of Internal Medicine, University of Genoa, 6 Viale Benedetto XV, 16132, Genoa, Italy.
- IRCCS Ospedale Policlinico San Martino Genoa-Italian Cardiovascular Network, Genoa, Italy.
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3
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Naish E, Wood AJT, Stewart AP, Routledge M, Morris AC, Chilvers ER, Lodge KM. The formation and function of the neutrophil phagosome. Immunol Rev 2023; 314:158-180. [PMID: 36440666 PMCID: PMC10952784 DOI: 10.1111/imr.13173] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Neutrophils are the most abundant circulating leukocyte and are crucial to the initial innate immune response to infection. One of their key pathogen-eliminating mechanisms is phagocytosis, the process of particle engulfment into a vacuole-like structure called the phagosome. The antimicrobial activity of the phagocytic process results from a collaboration of multiple systems and mechanisms within this organelle, where a complex interplay of ion fluxes, pH, reactive oxygen species, and antimicrobial proteins creates a dynamic antimicrobial environment. This complexity, combined with the difficulties of studying neutrophils ex vivo, has led to gaps in our knowledge of how the neutrophil phagosome optimizes pathogen killing. In particular, controversy has arisen regarding the relative contribution and integration of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-derived antimicrobial agents and granule-delivered antimicrobial proteins. Clinical syndromes arising from dysfunction in these systems in humans allow useful insight into these mechanisms, but their redundancy and synergy add to the complexity. In this article, we review the current knowledge regarding the formation and function of the neutrophil phagosome, examine new insights into the phagosomal environment that have been permitted by technological advances in recent years, and discuss aspects of the phagocytic process that are still under debate.
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Affiliation(s)
- Emily Naish
- National Heart and Lung InstituteImperial College LondonLondonUK
| | - Alexander JT Wood
- Medical SchoolUniversity of Western AustraliaPerthAustralia
- Department of Critical CareUniversity of MelbourneMelbourneAustralia
| | | | - Matthew Routledge
- Department of MedicineUniversity of CambridgeCambridgeUK
- Division of Immunology, Department of PathologyUniversity of CambridgeCambridgeUK
| | - Andrew Conway Morris
- Department of MedicineUniversity of CambridgeCambridgeUK
- Division of Immunology, Department of PathologyUniversity of CambridgeCambridgeUK
| | - Edwin R Chilvers
- National Heart and Lung InstituteImperial College LondonLondonUK
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Delidakis G, Kim JE, George K, Georgiou G. Improving Antibody Therapeutics by Manipulating the Fc Domain: Immunological and Structural Considerations. Annu Rev Biomed Eng 2022; 24:249-274. [PMID: 35363537 PMCID: PMC9648538 DOI: 10.1146/annurev-bioeng-082721-024500] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Interactions between the crystallizable fragment (Fc) domain of antibodies and a plethora of cellular Fc receptors (FcRs) or soluble proteins form a critical link between humoral and innate immunity. In particular, the immunoglobulin G Fc domain is critical for the clearance of target cells by processes that include (a) cytotoxicity, phagocytosis, or complement lysis; (b) modulation of inflammation; (c) antigen presentation; (d) antibody-mediated receptor clustering; and (e) cytokine release. More than 30 Fc-engineered antibodies aimed primarily at tailoring these effects for optimal therapeutic outcomes are in clinical evaluation or have already been approved. Nonetheless, our understanding of how FcR engagement impacts various immune cell phenotypes is still largely incomplete. Recent insights into FcR biology coupled with advances in Fc:FcR structural analysis, Fc engineering, and mouse models that recapitulate human biology are helping to fill in existing knowledge gaps. These advances will provide a blueprint on how to fine-tune the Fc domain to achieve optimal therapeutic efficacy. Expected final online publication date for the Annual Review of Biomedical Engineering, Volume 24 is June 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- George Delidakis
- Department of Chemical Engineering, University of Texas at Austin, Austin, Texas, USA;
| | - Jin Eyun Kim
- Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, USA
| | - Katia George
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, USA
| | - George Georgiou
- Department of Chemical Engineering, University of Texas at Austin, Austin, Texas, USA; .,Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, USA.,Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, USA
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Fuentes N, McCullough M, Panettieri RA, Druey KM. RGS proteins, GRKs, and beta-arrestins modulate G protein-mediated signaling pathways in asthma. Pharmacol Ther 2021; 223:107818. [PMID: 33600853 DOI: 10.1016/j.pharmthera.2021.107818] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/25/2021] [Indexed: 12/17/2022]
Abstract
Asthma is a highly prevalent disorder characterized by chronic lung inflammation and reversible airways obstruction. Pathophysiological features of asthma include episodic and reversible airway narrowing due to increased bronchial smooth muscle shortening in response to external and host-derived mediators, excessive mucus secretion into the airway lumen, and airway remodeling. The aberrant airway smooth muscle (ASM) phenotype observed in asthma manifests as increased sensitivity to contractile mediators (EC50) and an increase in the magnitude of contraction (Emax); collectively these attributes have been termed "airways hyper-responsiveness" (AHR). This defining feature of asthma can be promoted by environmental factors including airborne allergens, viruses, and air pollution and other irritants. AHR reduces airway caliber and obstructs airflow, evoking clinical symptoms such as cough, wheezing and shortness of breath. G-protein-coupled receptors (GPCRs) have a central function in asthma through their impact on ASM and airway inflammation. Many but not all treatments for asthma target GPCRs mediating ASM contraction or relaxation. Here we discuss the roles of specific GPCRs, G proteins, and their associated signaling pathways, in asthma, with an emphasis on endogenous mechanisms of GPCR regulation of ASM tone and lung inflammation including regulators of G-protein signaling (RGS) proteins, G-protein coupled receptor kinases (GRKs), and β-arrestin.
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Affiliation(s)
- Nathalie Fuentes
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH, Bethesda, MD, United States of America
| | - Morgan McCullough
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH, Bethesda, MD, United States of America
| | - Reynold A Panettieri
- Rutgers Institute for Translational Medicine and Science, Child Health Institute of New Jersey, Rutgers University School of Medicine, New Brunswick, NJ, United States of America
| | - Kirk M Druey
- Lung and Vascular Inflammation Section, Laboratory of Allergic Diseases, NIAID/NIH, Bethesda, MD, United States of America.
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Chang Y, Yin C, Peng H, Shi Y. Differentially proteomic analysis of the hemocytes against Aeromonas hydrophila infection in oriental river prawn Macrobrachium nipponense by iTRAQ approach. FISH & SHELLFISH IMMUNOLOGY 2020; 104:324-336. [PMID: 32553982 DOI: 10.1016/j.fsi.2020.06.032] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 05/21/2020] [Accepted: 06/13/2020] [Indexed: 06/11/2023]
Abstract
As the direct executors of biological function, the expression level of proteins in host will reveal the molecular mechanisms regulating bacteria infection more directly. In the present study, the differential proteomes of Macrobrachium nipponense hemocytes response to Aeromonas hydrophila infection were identified with isobaric tags for relative and absolute quantitation (iTRAQ) labeling followed by liquid chromatography electrospray ionization tandem mass spectrometry. The hemocyte proteins from the unchallenged and A. hydrophila challenged prawn, M. nipponense, at 12, 24 and 36 h post infection were compared. From this, a total of 3372 proteins were identified and 1014 proteins were considered differentially expressed, of which 117 common differentially expressed proteins were indicated between the time points. Hierarchical clustering, Gene Ontology, Kyoto Encyclopedia of Genes and Genomes enrichment and protein-protein interaction network analyses were performed for the general characterization of overall enriched proteins. Cytoskeletal proteins including myosin heavy chain, myosin regulatory light chain, actin, tubulin alpha/beta chain, troponin I and troponin T as well as antioxidant enzymes such as catalase and cytosolic MnSOD were found significantly up-regulated in hemocytes, indicating that the phagocytosis process and ROS system were induced after challenge with A. hydrophila. And other proteins such as integrin β, innexin inx2-like and heat shock protein 60 also participate in prawn immune response against bacteria. Parallel reaction monitoring analyses were carried out for validation of the expression levels of differentially expressed proteins, which indicated high reliability of the proteomic results. This is the first report on proteome of M. nipponense hemocytes against A. hydrophila infection, which contributes to better understanding on the molecular mechanisms of prawns.
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Affiliation(s)
- Yanhong Chang
- Department of Life Science and Engineering, Jining University, 1 Xingtan Road, Qufu, 273100, Shandong, China.
| | - Chunguang Yin
- Department of Life Science and Engineering, Jining University, 1 Xingtan Road, Qufu, 273100, Shandong, China
| | - Hao Peng
- Department of Life Science and Engineering, Jining University, 1 Xingtan Road, Qufu, 273100, Shandong, China
| | - Yanqiu Shi
- Department of Life Science and Engineering, Jining University, 1 Xingtan Road, Qufu, 273100, Shandong, China
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7
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Barger SR, Gauthier NC, Krendel M. Squeezing in a Meal: Myosin Functions in Phagocytosis. Trends Cell Biol 2019; 30:157-167. [PMID: 31836280 DOI: 10.1016/j.tcb.2019.11.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 11/11/2019] [Accepted: 11/14/2019] [Indexed: 12/21/2022]
Abstract
Phagocytosis is a receptor-mediated, actin-dependent process of internalization of large extracellular particles, such as pathogens or apoptotic cells. Engulfment of phagocytic targets requires the activity of myosins, actin-dependent molecular motors, which perform a variety of functions at distinct steps during phagocytosis. By applying force to actin filaments, the plasma membrane, and intracellular proteins and organelles, myosins can generate contractility, directly regulate actin assembly to ensure proper phagocytic internalization, and translocate phagosomes or other cargo to appropriate cellular locations. Recent studies using engineered microenvironments and phagocytic targets have demonstrated how altering the actomyosin cytoskeleton affects phagocytic behavior. Here, we discuss how studies using genetic and biochemical manipulation of myosins, force measurement techniques, and live-cell imaging have advanced our understanding of how specific myosins function at individual steps of phagocytosis.
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Affiliation(s)
- Sarah R Barger
- Cell and Developmental Biology Department, State University of New York Upstate Medical University, Syracuse, NY, USA
| | | | - Mira Krendel
- Cell and Developmental Biology Department, State University of New York Upstate Medical University, Syracuse, NY, USA.
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8
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Kakigi A, Okada T, Takeda T, Uehara N, Nibu KI. Endocytosis of CF in marginal cells of stria vascularis regulated by ROCK and MLCK signaling cascade, but not G-proteins. Auris Nasus Larynx 2019; 46:790-796. [PMID: 30739815 DOI: 10.1016/j.anl.2019.01.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/14/2019] [Accepted: 01/17/2019] [Indexed: 01/24/2023]
Abstract
Objective The endocytosis of cationized feritin (CF) via a clathrin-mediated pathway is regulated by a signaling network. Marginal cells showed the active endocytosis of CF via a clathrin-mediated pathway. The internalization of receptors through this clathrin-mediated pathway is an important regulatory event in signal transduction. Numerous kinases are involved in endocytosis, and each endocytic route is subjected to high-order regulation by cellular signaling mechanisms. In this study, we investigated whether ROCK and MLCK signaling cascades and G-proteins regulate the endocytosis of CF in marginal cells of the stria vascularis. Methods CF was infused into the cochlear duct with pertussis toxin (PTX),Clostridium botulinum C3 toxin (BTX), guanosine(g-thio)-triphosphate (GTP-γS), ML-7, Y-27632. Endocytic activity was measured at 30 min after the start of infusion under an electron microscope. Results In marginal cells, CF was internalized via a clathrin-mediated pathway that depends on F-actin and microtubules (MT). Its processes were controlled by myosin light chain kinase (MLCK) and Rho-associated kinase (ROCK), but not affected by G-protein-coupled receptor (GPCR) or the RhoA signaling cascade. Conclusion Our previous study showed that the main endocytotic pathway of microperoxidase (MPO) did not depend on the Rho/ROCK molecular switch or actin/myosin motor system, but was mainly regulated by the RhoA signaling cascade. The present study results indicate that these signaling cascades regulating CF internalization completely differ from the cascades for MPO internalization.
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Affiliation(s)
- Akinobu Kakigi
- Department of Otolaryngology-Head & Neck Surgery, Kobe University, Graduate School of Medicine, Hyogo, Japan.
| | - Teruhiko Okada
- Department of Anatomy, Kochi Medical School, Nankoku, Kochi, Japan
| | - Taizo Takeda
- Department of Otolaryngology, Kochi Medical School, Nankoku, Kochi, Japan
| | - Natsumi Uehara
- Department of Otolaryngology-Head & Neck Surgery, Kobe University, Graduate School of Medicine, Hyogo, Japan
| | - Ken-Ichi Nibu
- Department of Otolaryngology-Head & Neck Surgery, Kobe University, Graduate School of Medicine, Hyogo, Japan
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Short-Term Regulation of Fc γR-Mediated Phagocytosis by TLRs in Macrophages: Participation of 5-Lipoxygenase Products. Mediators Inflamm 2017; 2017:2086840. [PMID: 28894350 PMCID: PMC5574301 DOI: 10.1155/2017/2086840] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 06/08/2017] [Indexed: 12/19/2022] Open
Abstract
TLRs recognize a broad spectrum of microorganism molecules, triggering a variety of cellular responses. Among them, phagocytosis is a critical process for host defense. Leukotrienes (LTs), lipid mediators produced from 5-lipoxygenase (5-LO) enzyme, increase FcγR-mediated phagocytosis. Here, we evaluated the participation of TLR2, TLR3, TLR4, and TLR9 in FcγR-mediated phagocytosis and whether this process is modulated by LTs. Rat alveolar macrophages (AMs), murine bone marrow-derived macrophages (BMDMs), and peritoneal macrophages (PMs) treated with TLR2, TLR3, and TLR4 agonists, but not TLR9, enhanced IgG-opsonized sheep red blood cell (IgG-sRBC) phagocytosis. Pretreatment of AMs or BMDMs with drugs that block LT synthesis impaired the phagocytosis promoted by TLR ligands, and TLR potentiation was also abrogated in PMs and BMDMs from 5-LO−/− mice. LTB4 production induced by IgG engagement was amplified by TLR ligands, while cys-LTs were amplified by activation of TLR2 and TLR4, but not by TLR3. We also noted higher ERK1/2 phosphorylation in IgG-RBC-challenged cells when preincubated with TLR agonists. Furthermore, ERK1/2 inhibition by PD98059 reduced the phagocytic activity evoked by TLR agonists. Together, these data indicate that TLR2, TLR3, and TLR4 ligands, but not TLR9, amplify IgG-mediated phagocytosis by a mechanism which requires LT production and ERK-1/2 pathway activation.
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10
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Levin R, Grinstein S, Canton J. The life cycle of phagosomes: formation, maturation, and resolution. Immunol Rev 2017; 273:156-79. [PMID: 27558334 DOI: 10.1111/imr.12439] [Citation(s) in RCA: 194] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Phagocytosis, the regulated uptake of large particles (>0.5 μm in diameter), is essential for tissue homeostasis and is also an early, critical component of the innate immune response. Phagocytosis can be conceptually divided into three stages: phagosome, formation, maturation, and resolution. Each of these involves multiple reactions that require exquisite spatial and temporal orchestration. The molecular events underlying these stages are being unraveled and the current state of knowledge is briefly summarized in this article.
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Affiliation(s)
- Roni Levin
- Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada
| | - Sergio Grinstein
- Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada.,Department of Biochemistry, University of Toronto, Toronto, ON, Canada.,Keenan Research Centre of the Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, ON, Canada
| | - Johnathan Canton
- Program in Cell Biology, Hospital for Sick Children, Toronto, ON, Canada
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Ávila-Rodríguez D, Solano Agama C, González-Pozos S, Vicente Méndez-Méndez J, Ortiz Plata A, Arreola-Mendoza L, Mendoza-Garrido ME. The shift in GH3 cell shape and cell motility is dependent on MLCK and ROCK. Exp Cell Res 2017; 354:1-17. [PMID: 28300565 DOI: 10.1016/j.yexcr.2017.03.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Revised: 03/02/2017] [Accepted: 03/09/2017] [Indexed: 11/24/2022]
Abstract
Cytoskeletal organization, actin-myosin contractility and the cell membrane together regulate cell morphology in response to the cell environment, wherein the extracellular matrix (ECM) is an indispensable component. Plasticity in cell shape enables cells to adapt their migration mode to their surroundings. GH3 endocrine cells respond to different ECM proteins, acquiring different morphologies: a rounded on collagen I-III (C I-III) and an elongated on collagen IV (C IV). However, the identities of the molecules that participate in these responses remain unknown. Considering that actin-myosin contractility is crucial to maintaining cell shape, we analyzed the participation of MLCK and ROCK in the acquisition of cell shape, the generation of cellular tension and the cell motility mode. We found that a rounded shape with high cortical tension depends on MLCK and ROCK, whereas in cells with an elongated shape, MLCK is the primary protein responsible for cell spreading. Further, in cells with a slow and directionally persistent motility, MLCK predominates, while rapid and erratic movement is ROCK-dependent. This behavior also correlates with GTPase activation. Cells on C I-III exhibited higher Rho-GTPase activity than cells on C IV and vice versa with Rac-GTPase activity, showing a plastic response of GH3 cells to their environment, leading to the generation of different cytoskeleton and membrane organizations and resulting in two movement strategies, rounded and fibroblastoid-like.
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Affiliation(s)
- Dulce Ávila-Rodríguez
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico City, Mexico
| | - Carmen Solano Agama
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico City, Mexico
| | - Sirenia González-Pozos
- Central Laboratories, Center for Research and Advanced Studies (CINVESTAV), Mexico City, Mexico
| | - Juan Vicente Méndez-Méndez
- Center of Nanosciences and Micro and Nanotechnology (CNMN), National Polytechnic Institute, Mexico City, Mexico
| | - Alma Ortiz Plata
- Laboratory of Experimental Neuropathology, National Institute of Neurology and Neurosurgery, Manuel Velasco Suarez, Mexico City, Mexico
| | - Laura Arreola-Mendoza
- Department of Biosciences and Engineering, Center for Interdisciplinary Research and Studies on Environment and Development (CIIEMAD), National Polytechnic Institute, Mexico City, Mexico
| | - María E Mendoza-Garrido
- Department of Physiology, Biophysics and Neuroscience, Center for Research and Advanced Studies (CINVESTAV), Mexico City, Mexico.
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12
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Yang J, Yin S, Bi F, Liu L, Qin T, Wang H, Cao W. TIMAP repression by TGFβ and HDAC3-associated Smad signaling regulates macrophage M2 phenotypic phagocytosis. J Mol Med (Berl) 2016; 95:273-285. [PMID: 27709267 DOI: 10.1007/s00109-016-1479-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Revised: 08/23/2016] [Accepted: 09/26/2016] [Indexed: 11/30/2022]
Abstract
TIMAP (TGFβ-inhibited membrane-associated protein) is an endothelium-enriched TGFβ downstream protein and structurally belongs to the targeting subunit of myosin phosphatase; however, the mechanism of TGFβ repressing TIMAP and its functional relevance to TGFβ bioactivity remain largely unknown. Here, we report that TIMAP is reduced in TGFβ-elevated mouse fibrotic kidney and highly expressed in macrophages. TGFβ repression of TIMAP is associated with HDAC3 upregulation and its recruitment by Smad2/3 at the Smad binding element on TIMAP promoter, whereas specific HDAC3 inhibition reversed the TIMAP repression, suggesting that TGFβ transcriptionally downregulates TIMAP through HDAC3-associated Smad signaling. Further investigation showed that TIMAP over-expression interrupted TGFβ-associated Smad signaling and TIMAP repression by TGFβ correlated with TGFβ-induced macrophage M2 polarization markers, migration, and phagocytosis-the processes promoted by phosphorylation of the putative TIMAP substrate myosin light chain (MLC). Consistently, TIMAP dephosphorylated MLC in macrophages and TGFβ induced macrophage migration and phagocytosis in TIMAP- and MLC phosphorylation-dependent manners, suggesting that TIMAP dephosphorylation of MLC constitutes an essential regulatory loop mitigating TGFβ-associated macrophage M2 phenotypic activities. Given that hyperactive TGFβ often causes excessive macrophage phagocytic activities potentially leading to various chronic disorders, the strategies targeting HDAC3/TIMAP axis might improve TGFβ-associated pathological processes. KEY MESSAGE TIMAP is enriched in the endothelium and highly expressed in macrophages. TIMAP is suppressed by TGFβ via HDAC3-associated Smad signaling. TIMAP inhibits TGFβ signaling and TGFβ-associated macrophage M2 polarization. TIMAP dephosphorylation of MLC counteracts TGFβ-induced macrophage phagocytosis.
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Affiliation(s)
- Jun Yang
- Nanjing University School of Medicine, Jiangsu Key Laboratory of Molecular Medicine, 22 Hankou Road, Room 209, Science & Technology Building, Nanjing, 210093, China
| | - Shasha Yin
- Nanjing University School of Medicine, Jiangsu Key Laboratory of Molecular Medicine, 22 Hankou Road, Room 209, Science & Technology Building, Nanjing, 210093, China
| | - Fangfang Bi
- Nanjing University School of Medicine, Jiangsu Key Laboratory of Molecular Medicine, 22 Hankou Road, Room 209, Science & Technology Building, Nanjing, 210093, China
| | - Lin Liu
- Nanjing University School of Medicine, Jiangsu Key Laboratory of Molecular Medicine, 22 Hankou Road, Room 209, Science & Technology Building, Nanjing, 210093, China
| | - Tian Qin
- Nanjing University School of Medicine, Jiangsu Key Laboratory of Molecular Medicine, 22 Hankou Road, Room 209, Science & Technology Building, Nanjing, 210093, China
| | - Hongwei Wang
- Nanjing University School of Medicine, Jiangsu Key Laboratory of Molecular Medicine, 22 Hankou Road, Room 209, Science & Technology Building, Nanjing, 210093, China
| | - Wangsen Cao
- Nanjing University School of Medicine, Jiangsu Key Laboratory of Molecular Medicine, 22 Hankou Road, Room 209, Science & Technology Building, Nanjing, 210093, China.
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13
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Li L, Wu X, Yue HY, Zhu YC, Xu J. Myosin light chain kinase facilitates endocytosis of synaptic vesicles at hippocampal boutons. J Neurochem 2016; 138:60-73. [PMID: 27062289 DOI: 10.1111/jnc.13635] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 03/27/2016] [Accepted: 04/05/2016] [Indexed: 02/07/2023]
Abstract
At nerve terminals, endocytosis efficiently recycles vesicle membrane to maintain synaptic transmission under different levels of neuronal activity. Ca(2+) and its downstream signal pathways are critical for the activity-dependent regulation of endocytosis. An activity- and Ca(2+) -dependent kinase, myosin light chain kinase (MLCK) has been reported to regulate vesicle mobilization, vesicle cycling, and motility in different synapses, but whether it has a general contribution to regulation of endocytosis at nerve terminals remains unknown. We investigated this issue at rat hippocampal boutons by imaging vesicle endocytosis as the real-time retrieval of vesicular synaptophysin tagged with a pH-sensitive green fluorescence protein. We found that endocytosis induced by 200 action potentials (5-40 Hz) was slowed by acute inhibition of MLCK and down-regulation of MLCK with RNA interference, while the total amount of vesicle exocytosis and somatic Ca(2+) channel current did not change with MLCK down-regulation. Acute inhibition of myosin II similarly impaired endocytosis. Furthermore, down-regulation of MLCK prevented depolarization-induced phosphorylation of myosin light chain, an effect shared by blockers of Ca(2+) channels and calmodulin. These results suggest that MLCK facilitates vesicle endocytosis through activity-dependent phosphorylation of myosin downstream of Ca(2+) /calmodulin, probably as a widely existing mechanism among synapses. Our study suggests that MLCK is an important activity-dependent regulator of vesicle recycling in hippocampal neurons, which are critical for learning and memory. The kinetics of vesicle membrane endocytosis at nerve terminals has long been known to depend on activity and Ca(2+) . This study provides evidence suggesting that myosin light chain kinase increases endocytosis efficiency at hippocampal neurons by mediating Ca(2+) /calmodulin-dependent phosphorylation of myosin. The authors propose that this signal cascade may serve as a common pathway contributing to the activity-dependent regulation of vesicle endocytosis at synapses.
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Affiliation(s)
- Lin Li
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta, Georgia, USA
| | - Xiaomei Wu
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta, Georgia, USA.,Department of Neurochemistry, Institute of Nautical Medicine, Nantong University, Nantong, Jiangsu, China
| | - Hai-Yuan Yue
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta, Georgia, USA
| | - Yong-Chuan Zhu
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta, Georgia, USA
| | - Jianhua Xu
- Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta, Georgia, USA.,Department of Neurology, Medical College of Georgia, Augusta, Georgia, USA
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14
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Wu SH, Hsiao YT, Kuo CL, Yu FS, Hsu SC, Wu PP, Chen JC, Hsia TC, Liu HC, Hsu WH, Chung JG. Bufalin Inhibits NCI-H460 Human Lung Cancer Cell Metastasis In Vitro by Inhibiting MAPKs, MMPs, and NF-κB Pathways. THE AMERICAN JOURNAL OF CHINESE MEDICINE 2016; 43:1247-64. [PMID: 26446205 DOI: 10.1142/s0192415x15500718] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Bufalin, a component of Chan Su (a traditional Chinese medicine), has been known to have antitumor effects for thousands of years. In this study, we investigated its anti-metastasis effects on NCI-H460 lung cancer cells. Under sub-lethal concentrations (from 25 up to 100 nM), bufalin significantly inhibits the invasion and migration nature of NCI-H460 cells that were measured by Matrigel Cell Migration Assay and Invasion System. Bufalin also suppressed the enzymatic activity of matrix metalloproteinase (MMP)-9, which was examined by gelatin zymography methods. Western blotting revealed that bufalin depressed several key metastasis-related proteins, such as NF-κB, MMP-2, MMP-9, protein kinase C (PKC), phosphatidylinositol 3-kinase (PI3-K), phosphorylated Akt, growth factor receptor-bound protein 2 (GRB2), phosphorylated extracellular signal-regulated kinase (ERK), phosphorylated p38, and phosphorylated c-Jun NH2-terminal kinase (JNK). As evidenced by immunostaining and the electrophoretic mobility shift assay (EMSA), bufalin induced not only a decreased cytoplasmic NF-κB production, but also decreased its nuclear translocation. Several metastasis-related genes, including Rho-associated (Rho A), coiled-coil-containing protein kinase 1 (ROCK1), and focal adhesion kinase (FAK), were down-regulated after bufalin treatment. In conclusion, bufalin is effective in inhibiting the metastatic nature of NCI-H460 cells in low, sub-lethal concentrations. Such an effect involves many mechanisms including MMPs, mitogen-activated protein kinases (MAPKs) and NF-κB systems. Bufalin has a potential to evolve into an anti-metastasis drug for human lung cancer in the future.
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Affiliation(s)
- Shin-Hwar Wu
- Institute of Clinical Medical Science, China Medical University, Taichung 404, Taiwan.,Division of Critical Care Medicine, Department of Medicine, Changhua Christian Hospital, Changhua 505, Taiwan
| | - Yung-Ting Hsiao
- Department of Biological Science and Technology, China Medical University, Taichung 404, Taiwan
| | - Chao-Lin Kuo
- Department of Chinese Medicine Resources, China Medical University, Taichung 404, Taiwan
| | - Fu-Shun Yu
- School of Dentistry, China Medical University, Taichung 404, Taiwan
| | - Shu-Chun Hsu
- Department of Biological Science and Technology, China Medical University, Taichung 404, Taiwan
| | - Ping-Ping Wu
- School of Pharmacy, China Medical University, Taichung 404, Taiwan
| | - Jaw-Chyun Chen
- Department of Medicinal Botany and Health Applications, Da-Yeh University, Changhua 515, Taiwan
| | - Te-Chun Hsia
- Department of Internal Medicine, China Medical University Hospital, Taichung 404, Taiwan
| | - Hsin-Chung Liu
- Department of Chinese Medicine Resources, China Medical University, Taichung 404, Taiwan
| | - Wu-Huei Hsu
- Department of Internal Medicine, China Medical University, Taichung 404, Taiwan.,Department of Internal Medicine, China Medical University Hospital, Taichung 404, Taiwan
| | - Jing-Gung Chung
- Department of Chinese Medicine Resources, China Medical University, Taichung 404, Taiwan.,Department of Biotechnology, Asia University, Taichung 413, Taiwan
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15
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Petropoulos M, Karamolegkou G, Rosmaraki E, Tsakas S. Hydrogen peroxide signals E. coli phagocytosis by human polymorphonuclear cells; up-stream and down-stream pathway. Redox Biol 2015. [PMID: 26204503 PMCID: PMC4804100 DOI: 10.1016/j.redox.2015.07.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Hydrogen peroxide (Η2Ο2) is produced during a variety of cellular procedures. In this paper, the regulatory role of Η2Ο2, in Escherichia coli phagocytosis by the human polymorphonuclears, was investigated. White blood cells were incubated with dihydrorhodamine (DHR) in order to study H2O2 synthesis and E. coli-FITC to study phagocytosis. Flow cytometry revealed increased synthesis of H2O2 in polymorphonuclears which incorporated E. coli-FITC. The blocking of H2O2 synthesis by specific inhibitors, N-ethylmaleimide (ΝΕΜ) for NADPH oxidase and diethyldithiocarbamate (DDC) for superoxide dismutase (SOD), decreased E. coli phagocytosis, as well. Immunoblot analysis of white blood cell protein extracts revealed that the blocking of NADPH oxidase and SOD decreased ERK-1/2 phosphorylation, while it had no effect on JNK and p38. Confocal microscopy showed that phosphorylation of MAPKs and phagocytosis solely occur in the polymorphonuclear and not in mononuclear cells. The use of specific MAPKs inhibitors showed that all of them are necessary for phagocytosis, but only phospho-p38 affects H2O2 synthesis. The blocking of JNK phosphorylation, in the presence of E. coli, evoked a further decrease of cytoplasmic p47 thus increasing its translocation onto the plasma membrane for the assembly of NADPH oxidase. It appears that newly synthesised H2O2 invigorates the phosphorylation and action of ERK-1/2 in E. coli phagocytosis, while phospho-JNK and phospho-p38 appear to regulate H2O2 production. Phagocytosis by polymorphonuclears is accompanied by a targeted production of H2O2. H2O2 signals E. coli phagocytosis by invigorating ERK phosphorylation. Phosphorylation of p38, appears to be involved in H2O2 synthesis. Phospho-JNK appears to support a regulating mechanism for NADPH oxidase assembly.
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Affiliation(s)
| | | | | | - Sotiris Tsakas
- Laboratory of Biology, Department of Biology, University of Patras, Greece.
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16
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Andersen NJ, Boguslawski EB, Kuk CY, Chambers CM, Duesbery NS. Combined inhibition of MEK and mTOR has a synergic effect on angiosarcoma tumorgrafts. Int J Oncol 2015; 47:71-80. [PMID: 25955301 PMCID: PMC4485647 DOI: 10.3892/ijo.2015.2989] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 04/09/2015] [Indexed: 12/14/2022] Open
Abstract
Angiosarcoma (AS) is a rare neoplasm of endothelial origin that has limited treatment options and poor five-year survival. Using tumorgraft models, we previously showed that AS is sensitive to small-molecule inhibitors that target mitogen-activated/extracellular-signal-regulated protein kinase kinases 1 and 2 (MEK). The objective of this study was to identify drugs that combine with MEK inhibitors to more effectively inhibit AS growth. We examined the in vitro synergy between the MEK inhibitor PD0325901 and inhibitors of eleven common cancer pathways in melanoma cell lines and canine angiosarcoma cell isolates. Combination indices were calculated using the Chou-Talalay method. Optimized combination therapies were evaluated in vivo for toxicity and efficacy using canine angiosarcoma tumorgrafts. Among the drugs we tested, rapamycin stood out because it showed strong synergy with PD0325901 at nanomolar concentrations. We observed that angiosarcomas are insensitive to mTOR inhibition. However, treatment with nanomolar levels of mTOR inhibitor renders these cells as sensitive to MEK inhibition as a melanoma cell line with mutant BRAF. Similar results were observed in B-Raf wild-type melanoma cells as well as in vivo, where treatment of canine AS tumorgrafts with MEK and mTOR inhibitors was more effective than monotherapy. Our data show that a low dose of an mTOR inhibitor can dramatically enhance angiosarcoma and melanoma response to MEK inhibition, potentially widening the field of applications for MEK-targeted therapy.
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Affiliation(s)
- Nicholas J Andersen
- Laboratory of Cancer and Developmental Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Elissa B Boguslawski
- Laboratory of Cancer and Developmental Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Cynthia Y Kuk
- Laboratory of Cancer and Developmental Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
| | - Christopher M Chambers
- Frederik Meijer Heart and Vascular Institute, Spectrum Health Hospital, Grand Rapids, MI 49503, USA
| | - Nicholas S Duesbery
- Laboratory of Cancer and Developmental Cell Biology, Van Andel Research Institute, Grand Rapids, MI 49503, USA
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17
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Maxeiner S, Shi N, Schalla C, Aydin G, Hoss M, Vogel S, Zenke M, Sechi AS. Crucial role for the LSP1-myosin1e bimolecular complex in the regulation of Fcγ receptor-driven phagocytosis. Mol Biol Cell 2015; 26:1652-64. [PMID: 25717183 PMCID: PMC4436777 DOI: 10.1091/mbc.e14-05-1005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 02/19/2015] [Indexed: 01/24/2023] Open
Abstract
The actin cytoskeleton is fundamental for the innate immune process of phagocytosis. This study shows that LSP1 plays a pivotal role in the regulation of actin cytoskeleton remodeling during Fcγ receptor–mediated phagocytosis and that its interactions with myosin1e and actin are crucial for the efficiency of this actin-driven process. Actin cytoskeleton remodeling is fundamental for Fcγ receptor–driven phagocytosis. In this study, we find that the leukocyte-specific protein 1 (LSP1) localizes to nascent phagocytic cups during Fcγ receptor–mediated phagocytosis, where it displays the same spatial and temporal distribution as the actin cytoskeleton. Down-regulation of LSP1 severely reduces the phagocytic activity of macrophages, clearly demonstrating a crucial role for this protein in Fcγ receptor–mediated phagocytosis. We also find that LSP1 binds to the class I molecular motor myosin1e. LSP1 interacts with the SH3 domain of myosin1e, and the localization and dynamics of both proteins in nascent phagocytic cups mirror those of actin. Furthermore, inhibition of LSP1–myosin1e and LSP1–actin interactions profoundly impairs pseudopodial formation around opsonized targets and their subsequent internalization. Thus the LSP1–myosin1e bimolecular complex plays a pivotal role in the regulation of actin cytoskeleton remodeling during Fcγ receptor–driven phagocytosis.
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Affiliation(s)
- Sebastian Maxeiner
- Institute of Biomedical Engineering, Department of Cell Biology, Applied Ecology, D-52074 Aachen, Germany
| | - Nian Shi
- Institute of Biomedical Engineering, Department of Cell Biology, Applied Ecology, D-52074 Aachen, Germany
| | - Carmen Schalla
- Institute of Biomedical Engineering, Department of Cell Biology, Applied Ecology, D-52074 Aachen, Germany
| | - Guelcan Aydin
- Institute of Biomedical Engineering, Department of Cell Biology, Applied Ecology, D-52074 Aachen, Germany
| | - Mareike Hoss
- Electron Microscopy Facility, Uniklinik RWTH Aachen, Applied Ecology, D-52074 Aachen, Germany
| | - Simon Vogel
- Fraunhofer Institute for Molecular Biology and Applied Ecology, D-52074 Aachen, Germany
| | - Martin Zenke
- Institute of Biomedical Engineering, Department of Cell Biology, Applied Ecology, D-52074 Aachen, Germany
| | - Antonio S Sechi
- Institute of Biomedical Engineering, Department of Cell Biology, Applied Ecology, D-52074 Aachen, Germany
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18
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Balenga NA, Jester W, Jiang M, Panettieri RA, Druey KM. Loss of regulator of G protein signaling 5 promotes airway hyperresponsiveness in the absence of allergic inflammation. J Allergy Clin Immunol 2014; 134:451-9. [PMID: 24666695 PMCID: PMC4119844 DOI: 10.1016/j.jaci.2014.01.019] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 01/24/2014] [Accepted: 01/27/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND Although eosinophilic inflammation typifies allergic asthma, it is not a prerequisite for airway hyperresponsiveness (AHR), suggesting that underlying abnormalities in structural cells, such as airway smooth muscle (ASM), contribute to the asthmatic diathesis. Dysregulation of procontractile G protein-coupled receptor (GPCR) signaling in ASM could mediate enhanced contractility. OBJECTIVE We explored the role of a regulator of procontractile GPCR signaling, regulator of G protein signaling 5 (RGS5), in unprovoked and allergen-induced AHR. METHODS We evaluated GPCR-evoked Ca(2+) signaling, precision-cut lung slice (PCLS) contraction, and lung inflammation in naive and Aspergillus fumigatus-challenged wild-type and Rgs5(-/-) mice. We analyzed lung resistance and dynamic compliance in live anesthetized mice using invasive plethysmography. RESULTS Loss of RGS5 promoted constitutive AHR because of enhanced GPCR-induced Ca(2+) mobilization in ASM. PCLSs from naive Rgs5(-/-) mice contracted maximally at baseline independently of allergen challenge. RGS5 deficiency had little effect on the parameters of allergic inflammation, including cell counts in bronchoalveolar lavage fluid, mucin production, ASM mass, and subepithelial collagen deposition. Unexpectedly, induced IL-13 and IL-33 levels were much lower in challenged lungs from Rgs5(-/-) mice relative to those seen in wild-type mice. CONCLUSION Loss of RGS5 confers spontaneous AHR in mice in the absence of allergic inflammation. Because it is selectively expressed in ASM within the lung and does not promote inflammation, RGS5 might be a therapeutic target for asthma.
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Affiliation(s)
- Nariman A Balenga
- Molecular Signal Transduction Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Bethesda, Md
| | - William Jester
- Pulmonary, Allergy and Critical Care Division, Airways Biology Initiative, University of Pennsylvania, Philadelphia, Pa
| | - Meiqi Jiang
- Pulmonary, Allergy and Critical Care Division, Airways Biology Initiative, University of Pennsylvania, Philadelphia, Pa
| | - Reynold A Panettieri
- Pulmonary, Allergy and Critical Care Division, Airways Biology Initiative, University of Pennsylvania, Philadelphia, Pa
| | - Kirk M Druey
- Molecular Signal Transduction Section, Laboratory of Allergic Diseases, National Institute of Allergy and Infectious Diseases/National Institutes of Health, Bethesda, Md.
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19
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Wang L, Sun X, Zhou Z, Zhang T, Yi Q, Liu R, Wang M, Song L. The promotion of cytoskeleton integration and redox in the haemocyte of shrimp Litopenaeus vannamei after the successive stimulation of recombinant VP28. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 45:123-132. [PMID: 24594136 DOI: 10.1016/j.dci.2014.02.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 02/17/2014] [Accepted: 02/20/2014] [Indexed: 06/03/2023]
Abstract
VP28 protein has been reported to work as a "vaccine" to protect the host from white spot syndrome, but the detailed mechanism of vaccination with VP28 protein in shrimp is still far from well understood. In the present study, whole transcriptomes of shrimp haemocytes were sequenced using the SOLiD4 platform after the successive VP28 stimulation. Eight single-end fragment libraries were constructed and sequenced in the four groups including the VP28-VP28, PBS-VP28, PBS-PBS and BLANK group, and there were 243,949,667 single-end reads with length of 50bp obtained totally, with 14,800 genes further identified. After reads mapping and transcript assembling, 1027, 1539, 1158, 1091 and 1300 genes in five differentially expressed gene lists were obtained in the comparison of VP28-VP28 versus PBS-VP28, VP28-VP28 versus PBS-PBS, VP28-VP28 versus BLANK, PBS-VP28 versus PBS-PBS and PBS-VP28 versus BLANK, respectively. There were 555 differentially expressed genes responsive to the single VP28 stimulation after grouping the PBS-VP28_BLANK and PBS-VP28_PBS-PBS gene lists, and 269 ones responsive to the successive VP28 stimulation after grouping the VP28-VP28_BLANK, VP28-VP28_PBS-PBS and VP28-VP28_PBS-VP28 gene lists. In the GO enrichment analysis of the genes responsive to the single VP28 stimulation, five immune-related GO terms were observed among 14 increased terms, which included defense response to bacterium, response to stimulus, disruption of cells of other organism, killing of cells of other organism and response to bacterium. It was worth noting that the GO terms, response to stimulus and response to stress, were the most common annotation ones which accounted 28.7% and 18.8% of the total differently expressed genes, respectively. For the genes responsive to the successive VP28 stimulation, terms including actin filament-based movement and myosin heavy chain binding were mostly enriched in the Biological Process and Molecular Function category, respectively. In the Cellular Component category, the enriched GO terms were myosin VII complex, myosin V complex, myosin VI complex and myosin II complex. Furthermore, the most abundant GO term was oxidation-reduction process, followed by single-organism transport, neurogenesis and translation for 214 genes only responsive to successive VP28 stimulation. These results collectively indicated that the successive VP28 stimulation could modulate cytoskeleton integration and redox to promote the phagocytosis activity of shrimp haemocytes, which might protect effectively for shrimp against WSSV infection.
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Affiliation(s)
- Lingling Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Xin Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhi Zhou
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Tao Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Qilin Yi
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Liu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Mengqiang Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Linsheng Song
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
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20
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Zhang T, Qiu L, Sun Z, Wang L, Zhou Z, Liu R, Yue F, Sun R, Song L. The specifically enhanced cellular immune responses in Pacific oyster (Crassostrea gigas) against secondary challenge with Vibrio splendidus. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2014; 45:141-150. [PMID: 24607288 DOI: 10.1016/j.dci.2014.02.015] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 02/26/2014] [Accepted: 02/28/2014] [Indexed: 06/03/2023]
Abstract
The increasing experimental evidences suggest that there are some forms of specific acquired immunity in invertebrates, but the underlying mechanism is not fully understood. In the present study, Pacific oyster (Crassostrea gigas) stimulated primarily by heat-killed Vibrio splendidus displayed stronger immune responses at cellular and molecular levels when they encountered the secondary challenge of live V. splendidus. The total hemocyte counts (THC) increased significantly after the primary stimulation of heat-killed V. splendidus, and it increased even higher (p < 0.01) and reached the peak earlier (at 6 h) after the secondary challenge with live V. splendidus compared with that of the primary stimulation. The number of new generated circulating hemocytes increased dramatically (p < 0.01) at 6 h after the pre-stimulated oysters received the secondary stimulation with live V. splendidus, and the phagocytic rate was also enhanced significantly (p < 0.01) at 12 h after the secondary stimulation. Meanwhile, the enhanced phagocytosis of hemocytes was highly specific for V. splendidus and they could distinguish Vibrio anguillarum, Vibrio coralliilyticus, Yarrowia lipolytica, and Micrococcus luteus efficiently. In addition, the mRNA expression of 12 candidate genes related to phagocytosis and hematopoiesis were also monitored, and the expression levels of CgIntegrin, CgPI3K (phosphatidylinositol 3-kinase), CgRho J, CgMAPKK (mitogen-activated protein kinase kinase), CgRab32, CgNADPH (nicotinamide adenine dinucleotide phosphate) oxidase, CgRunx1 and CgBMP7 (bone morphogenetic protein 7) in the hemocytes of pre-stimulated oysters after the secondary stimulation of V. splendidus were higher (p < 0.01) than that after the primary stimulation, but there was no statistically significant changes for the genes of CgPKC (protein kinase C), CgMyosin, CgActin, and CgGATA 3. These results collectively suggested that the primary stimulation of V. splendidus led to immune priming in oyster with specifically enhanced phagocytosis and rapidly promoted regeneration of circulating hemocytes when the primed oysters encountered the secondary challenge with V. splendidus.
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Affiliation(s)
- Tao Zhang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Limei Qiu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Zhibin Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Lingling Wang
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Zhi Zhou
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Rui Liu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China
| | - Feng Yue
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Sun
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Linsheng Song
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China.
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21
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Liu C, Wang J, Zhang X. The involvement of MiR-1-clathrin pathway in the regulation of phagocytosis. PLoS One 2014; 9:e98747. [PMID: 24932654 PMCID: PMC4059620 DOI: 10.1371/journal.pone.0098747] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2013] [Accepted: 05/07/2014] [Indexed: 11/19/2022] Open
Abstract
Phagocytosis, one of the most powerful immune responses, is a complicated process regulated by many factors. However the regulation of phagocytosis mediated by microRNAs has not been extensively investigated. To address this issue, the regulation of phagocytosis by miR-1 was characterized in this study. The results showed that miR-1 played an important role in the phagocytosis regulation in shrimp in vivo. The sequence analysis indicated that miR-1 was highly conserved from invertebrates to mammals, suggesting that miR-1 might share the similar or same functions in phagocytosis of shrimp hemocytes and mammalian macrophages. The data presented that miR-1 was significantly downregulated in cancerous macrophage RAW264.7 cells compared with those in the isolated murine macrophage and in the immortalized macrophage ANA-1. The findings showed that miR-1 had a great effect on the regulation of phagocytosis in cancerous macrophage by the inhibition of clathrin heavy chain 1 (CLTC1) gene. Therefore our study presented a novel miR-1-mediated regulation of phagocytosis both in invertebrate and in vertebrate.
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Affiliation(s)
- Cuilian Liu
- Key Laboratory of Animal Virology of Ministry of Agriculture and College of Life Sciences, Zhejiang University, Hangzhou, The People's Republic of China
| | - Jiajia Wang
- Key Laboratory of Animal Virology of Ministry of Agriculture and College of Life Sciences, Zhejiang University, Hangzhou, The People's Republic of China
| | - Xiaobo Zhang
- Key Laboratory of Animal Virology of Ministry of Agriculture and College of Life Sciences, Zhejiang University, Hangzhou, The People's Republic of China
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22
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Epidermal growth factor receptor-PI3K signaling controls cofilin activity to facilitate herpes simplex virus 1 entry into neuronal cells. mBio 2014; 5:e00958-13. [PMID: 24425731 PMCID: PMC3903278 DOI: 10.1128/mbio.00958-13] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Herpes simplex virus type 1 (HSV-1) establishes latency in neurons and can cause severe disseminated infection with neurological impairment and high mortality. This neurodegeneration is thought to be tightly associated with virus-induced cytoskeleton disruption. Currently, the regulation pattern of the actin cytoskeleton and the involved molecular mechanisms during HSV-1 entry into neurons remain unclear. Here, we demonstrate that the entry of HSV-1 into neuronal cells induces biphasic remodeling of the actin cytoskeleton and an initial inactivation followed by the subsequent activation of cofilin, a member of the actin depolymerizing factor family that is critical for actin reorganization. The disruption of F-actin dynamics or the modulation of cofilin activity by mutation, knockdown, or overexpression affects HSV-1 entry efficacy and virus-mediated cell ruffle formation. Binding of the HSV-1 envelope initiates the epidermal growth factor receptor (EGFR)-phosphatidylinositide 3-kinase (PI3K) signaling pathway, which leads to virus-induced early cofilin phosphorylation and F-actin polymerization. Moreover, the extracellular signal-regulated kinase (ERK) kinase and Rho-associated, coiled-coil-containing protein kinase 1 (ROCK) are recruited as downstream mediators of the HSV-1-induced cofilin inactivation pathway. Inhibitors specific for those kinases significantly reduce the virus infectivity without affecting virus binding to the target cells. Additionally, lipid rafts are clustered to promote EGFR-associated signaling cascade transduction. We propose that HSV-1 hijacks cofilin to initiate infection. These results could promote a better understanding of the pathogenesis of HSV-1-induced neurological diseases. The actin cytoskeleton is involved in many crucial cellular processes and acts as an obstacle to pathogen entry into host cells. Because HSV-1 establishes lifelong latency in neurons and because neuronal cytoskeletal disruption is thought to be the main cause of HSV-1-induced neurodegeneration, understanding the F-actin remodeling pattern by HSV-1 infection and the molecular interactions that facilitate HSV-1 entry into neurons is important. In this study, we showed that HSV-1 infection induces the rearrangement of the cytoskeleton as well as the initial inactivation and subsequent activation of cofilin. Then, we determined that activation of the EGFR-PI3K-Erk1/2 signaling pathway inactivates cofilin and promotes F-actin polymerization. We postulate that by regulating actin cytoskeleton dynamics, cofilin biphasic activation could represent the specific cellular machinery usurped by pathogen infection, and these results will greatly contribute to the understanding of HSV-1-induced early and complex changes in host cells that are closely linked to HSV-1 pathogenesis.
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Antoine TE, Shukla D. Inhibition of myosin light chain kinase can be targeted for the development of new therapies against herpes simplex virus type-1 infection. Antivir Ther 2013; 19:15-29. [PMID: 23813409 DOI: 10.3851/imp2661] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/26/2013] [Indexed: 10/26/2022]
Abstract
BACKGROUND Herpes simplex virus type-1 (HSV-1) is the leading cause of infectious blindness worldwide. Through a multistep process, HSV-1 enters into naturally susceptible human corneal epithelial (HCE) cells where it establishes an optimal environment for viral replication and spread. HSV-1 employment of cytoskeletal proteins, kinases, and cell signalling pathways is crucial for the entry process. METHODS Here we demonstrate that non-muscle myosin IIA (NM-IIA) and/or a myosin activating kinase, myosin light chain kinase (MLCK), can be targeted for the development of new and effective therapies against HSV-1. HCE cells were incubated with MLCK inhibitors ML-7 and ML-9 and NM-IIA inhibitor blebbistatin. Following the application of inhibitors, HSV-1 entry and spread to neighbouring HCE cells was evaluated. RESULTS Upon application of MLCK inhibitors ML-7 and ML-9 and NM-IIA inhibitor blebbistatin, HSV-1 entry into HCE cells was significantly decreased. Furthermore, dramatic impairment of glycoprotein-mediated membrane fusion was seen in cells treated with MLCK inhibitors, thus establishing a role for MLCK activation in cell-to-cell fusion and multinucleated syncytial cell formation. These results also indicate that the activation of motor protein NM-IIA by MLCK is crucial for cytoskeletal changes required for HSV-1 infection of corneal cells. CONCLUSIONS We provide new evidence that NM-IIA and MLCK can be used as effective antiviral targets against ocular herpes.
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Affiliation(s)
- Thessicar E Antoine
- Department of Ophthalmology & Visual Sciences, University of Illinois at Chicago, Chicago, IL, USA
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Taengchaiyaphum S, Havanapan PO, Roytrakul S, Lo CF, Sritunyalucksana K, Krittanai C. Phosphorylation is required for myosin regulatory light chain (PmMRLC) to control yellow head virus infection in shrimp hemocytes. FISH & SHELLFISH IMMUNOLOGY 2013; 34:1042-1049. [PMID: 23337109 DOI: 10.1016/j.fsi.2012.12.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 12/17/2012] [Accepted: 12/23/2012] [Indexed: 06/01/2023]
Abstract
The cellular signal-transduction process is largely controlled by protein phosphorylation. Shrimp infected with yellow head virus show dramatic changes in their hemocyte phosphoproteomic patterns, and aberrant activation of phosphorylation-based signaling networks has been implicated in a number of diseases. In this study, we focused on phosphorylation of Penaeus monodon myosin regulatory light chain (PmMRLC) that is induced at an early hour post YHV infection and is concomitant with cellular actin remodeling. In shrimp cell cultures, this phosphorylation was inhibited by the myosin light chain kinase (MLCK) inhibitors ML-7 and ML-9, suggesting that PmMLC phosphorylation is MLCK pathway-dependent. Blocking PmMRLC phosphorylation resulted in increased replication of YHV and reduction of phagocytic activities of shrimp hemocytes called semigranular cells (SGC) and granular cells (GC). Injection of MLCK inhibitors prior to YHV challenge resulted in dose-dependent elevation in quantity of YHV-positive GC and cytoplasmic YHV protein, coincident with high shrimp mortality. Altogether, we demonstrated that PmMRLC phosphorylation increases after YHV infection in shrimp and that inhibition of the phosphorylation leads to increased YHV replication, reduced hemocyte phagocytic activity (probably through actin remodeling) and subsequent shrimp death. Thus, further studies on the MLCK activation pathway may lead to new strategies in development and implementation of therapy for YHV infections in shrimp.
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MESH Headings
- Amino Acid Sequence
- Animals
- Blotting, Western
- Chromatography, Liquid
- Cloning, Molecular
- DNA, Complementary/genetics
- DNA, Complementary/metabolism
- Electrophoresis, Gel, Two-Dimensional
- Fluorescent Antibody Technique
- Hemocytes/chemistry
- Hemocytes/metabolism
- Hemocytes/virology
- Molecular Sequence Data
- Myosin Light Chains/chemistry
- Myosin Light Chains/genetics
- Myosin Light Chains/metabolism
- Penaeidae/chemistry
- Penaeidae/genetics
- Penaeidae/metabolism
- Penaeidae/virology
- Phosphoproteins/chemistry
- Phosphoproteins/genetics
- Phosphoproteins/metabolism
- Phosphorylation
- Phylogeny
- Proteome/chemistry
- Proteome/genetics
- Proteome/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Roniviridae/immunology
- Sequence Alignment
- Sequence Analysis, DNA
- Tandem Mass Spectrometry
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Affiliation(s)
- Suparat Taengchaiyaphum
- Institute of Molecular Biosciences, Mahidol University, Salaya Campus, Salaya, Nakhonpathom 73170, Thailand
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25
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Systemic treatment with the inhibitory neurotransmitter γ-aminobutyric acid aggravates experimental autoimmune encephalomyelitis by affecting proinflammatory immune responses. J Neuroimmunol 2012. [PMID: 23194644 DOI: 10.1016/j.jneuroim.2012.11.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Transcriptomic and proteomic analyses of multiple sclerosis (MS) lesions indicate alterations in the gamma-aminobutyric acid (GABA) inhibitory system, suggesting its involvement in the disease process. To further elucidate the role of GABA in central nervous system (CNS) inflammation in vivo, the chronic myelin oligodendrocyte glycoprotein (MOG)(35-55) experimental autoimmune encephalomyelitis (EAE) model was used. Daily GABA injections (200mg/kg) from day 3 onwards significantly augmented disease severity, which was associated with increased CNS mRNA expression levels of tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6. GABA-treated mice showed enhanced MOG-dependent proliferation and were skewed towards a T helper 1 phenotype. Moreover, in vitro, the lipopolysaccharide (LPS)-induced increase in interleukin (IL)-6 production by macrophages was enhanced at low GABA concentrations (0.03-0.3mM). In sharp contrast to exogenous GABA administration, endogenous GABA increment by systemic treatment with the GABA-transaminase inhibitor vigabatrin (250mg/kg) had prophylactic as well as therapeutic potential in EAE. Together, these results indicate an immune amplifying role of GABA in neuroinflammatory diseases like MS.
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Bromberg-White JL, Andersen NJ, Duesbery NS. MEK genomics in development and disease. Brief Funct Genomics 2012; 11:300-10. [PMID: 22753777 PMCID: PMC3398258 DOI: 10.1093/bfgp/els022] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The mitogen-activated protein kinase kinases (the MAPK/ERK kinases; MKKs or MEKs) and their downstream substrates, the extracellular-regulated kinases have been intensively studied for their roles in development and disease. Until recently, it had been assumed any mutation affecting their function would have lethal consequences. However, the identification of MEK1 and MEK2 mutations in developmental syndromes as well as chemotherapy-resistant tumors, and the discovery of genomic variants in MEK1 and MEK2 have led to the realization the extent of genomic variation associated with MEKs is much greater than had been appreciated. In this review, we will discuss these recent advances, relating them to what is currently understood about the structure and function of MEKs, and describe how they change our understanding of the role of MEKs in development and disease.
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Affiliation(s)
- Jennifer L Bromberg-White
- Laboratory of Cancer and Developmental Cell Biology, Van Andel Research Institute, 333 Bostwick Avenue NE, Grand Rapids, MI 49503, USA
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27
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Flannagan RS, Jaumouillé V, Grinstein S. The Cell Biology of Phagocytosis. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2012; 7:61-98. [PMID: 21910624 DOI: 10.1146/annurev-pathol-011811-132445] [Citation(s) in RCA: 652] [Impact Index Per Article: 54.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ronald S. Flannagan
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada;
| | - Valentin Jaumouillé
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada;
| | - Sergio Grinstein
- Program in Cell Biology, Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada;
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Usatyuk PV, Singleton PA, Pendyala S, Kalari SK, He D, Gorshkova IA, Camp SM, Moitra J, Dudek SM, Garcia JGN, Natarajan V. Novel role for non-muscle myosin light chain kinase (MLCK) in hyperoxia-induced recruitment of cytoskeletal proteins, NADPH oxidase activation, and reactive oxygen species generation in lung endothelium. J Biol Chem 2012; 287:9360-75. [PMID: 22219181 DOI: 10.1074/jbc.m111.294546] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
We recently demonstrated that hyperoxia (HO) activates lung endothelial cell NADPH oxidase and generates reactive oxygen species (ROS)/superoxide via Src-dependent tyrosine phosphorylation of p47(phox) and cortactin. Here, we demonstrate that the non-muscle ~214-kDa myosin light chain (MLC) kinase (nmMLCK) modulates the interaction between cortactin and p47(phox) that plays a role in the assembly and activation of endothelial NADPH oxidase. Overexpression of FLAG-tagged wild type MLCK in human pulmonary artery endothelial cells enhanced interaction and co-localization between cortactin and p47(phox) at the cell periphery and ROS production, whereas abrogation of MLCK using specific siRNA significantly inhibited the above. Furthermore, HO stimulated phosphorylation of MLC and recruitment of phosphorylated and non-phosphorylated cortactin, MLC, Src, and p47(phox) to caveolin-enriched microdomains (CEM), whereas silencing nmMLCK with siRNA blocked recruitment of these components to CEM and ROS generation. Exposure of nmMLCK(-/-) null mice to HO (72 h) reduced ROS production, lung inflammation, and pulmonary leak compared with control mice. These results suggest a novel role for nmMLCK in hyperoxia-induced recruitment of cytoskeletal proteins and NADPH oxidase components to CEM, ROS production, and lung injury.
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Affiliation(s)
- Peter V Usatyuk
- Department of Pharmacology, University of Illinois, Chicago, Illinois 60612, USA
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29
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The MAPK MEK1/2-ERK1/2 Pathway and Its Implication in Hepatocyte Cell Cycle Control. Int J Hepatol 2012; 2012:328372. [PMID: 23133759 PMCID: PMC3485978 DOI: 10.1155/2012/328372] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 09/06/2012] [Accepted: 09/10/2012] [Indexed: 12/15/2022] Open
Abstract
Primary cultures of hepatocytes are powerful models in studying the sequence of events that are necessary for cell progression from a G0-like state to S phase. The models mimic the physiological process of hepatic regeneration after liver injury or partial hepatectomy. Many reports suggest that the mitogen-activated protein kinase (MAPK) ERK1/2 can support hepatocyte proliferation in vitro and in vivo and the MEK/ERK cascade acts as an essential element in hepatocyte responses induced by the EGF. Moreover, its disregulation has been associated with the promotion of tumor cell growth of a variety of tumors, including hepatocellular carcinoma. Whereas the strict specificity of action of ERK1 and ERK2 is still debated, the MAPKs may have specific biological functions under certain contexts and according to the differentiation status of the cells, notably hepatocytes. In this paper, we will focus on MEK1/2-ERK1/2 activations and roles in normal rodent hepatocytes in vitro and in vivo after partial hepatectomy and in human hepatocarcinoma cells. The possible specificity of ERK1 and ERK2 in normal and transformed hepatocyte will be discussed in regard to other differentiated and undifferentiated cellular models.
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Carignan D, Désy O, de Campos-Lima PO. The dysregulation of the monocyte/macrophage effector function induced by isopropanol is mediated by the defective activation of distinct members of the AP-1 family of transcription factors. Toxicol Sci 2011; 125:144-56. [PMID: 22020770 DOI: 10.1093/toxsci/kfr283] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Isopropanol is the second most common cause of short-chain alcohol acute intoxication. Nonethanolic short-chain alcohols mediate their immunomodulatory effect by interfering with nuclear factor of activated T cells (NFAT) activation with or without additional activator protein-1 (AP-1) involvement. In the present study, we examined the immunomodulation induced by isopropanol in conditions that are not reliant on NFAT: the inflammatory cytokine response of lipopolysaccharide (LPS)-stimulated monocytes. Our hypothesis was that isopropanol acute exposure would have an attenuated effect or no consequence in this setting. To our surprise, the impairment of AP-1 activation was sufficient to mediate a severe and dose-dependent phenotype in human monocytes in vitro at alcohol concentrations as low as 0.16% (or 26 mM). There were three outcomes: interleukin (IL)-1β/IL-8 were unaltered; IL-6 was upregulated; and tumor necrosis factor alpha (TNF-α)/CCL2 were downregulated. The effector function of human monocyte-derived macrophages was also compromised. Our results showed that Toll-like receptor 4 early signaling was preserved, as isopropanol did not change the kinase activity of the IL-1 receptor-associated kinase 1 in LPS-stimulated cells. The nuclear factor-κB signaling cascade and the p38/c-Jun N-terminal kinase modules of the mitogen-activated protein kinase pathway were alcohol insensitive. Conversely, the activation of extracellular signal-regulated protein kinase and, ultimately, of c-Fos and JunB were impaired. The alcohol-induced cytokine dysregulation was confirmed in a mouse model of isopropanol intoxication in which the production of TNF-α in response to LPS challenge was virtually abolished. The magnitude of this alcohol effect was sufficiently high to rescue animals from LPS-induced toxic shock. Our data contribute to the dismal body of information on the immunotoxicology of isopropanol, one of the most ubiquitous chemicals to which the general population is significantly exposed.
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Affiliation(s)
- Damien Carignan
- Laval University Cancer Research Center, Quebec City, Quebec G1R 2J6, Canada
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31
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Romero S, Grompone G, Carayol N, Mounier J, Guadagnini S, Prevost MC, Sansonetti PJ, Van Nhieu GT. ATP-mediated Erk1/2 activation stimulates bacterial capture by filopodia, which precedes Shigella invasion of epithelial cells. Cell Host Microbe 2011; 9:508-19. [PMID: 21669399 DOI: 10.1016/j.chom.2011.05.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Revised: 04/19/2011] [Accepted: 05/23/2011] [Indexed: 11/29/2022]
Abstract
Shigella, the causative agent of bacillary dysentery in humans, invades epithelial cells, using a type III secretory system (T3SS) to inject bacterial effectors into host cells and remodel the actin cytoskeleton. ATP released through connexin hemichanels on the epithelial membrane stimulates Shigella invasion and dissemination in epithelial cells. Here, we show that prior to contact with the cell body, Shigella is captured by nanometer-thin micropodial extensions (NMEs) at a distance from the cell surface, in a process involving the T3SS tip complex proteins and stimulated by ATP- and connexin-mediated signaling. Upon bacterial contact, NMEs retract, bringing bacteria in contact with the cell body, where invasion occurs. ATP stimulates Erk1/2 activation, which controls actin retrograde flow in NMEs and their retraction. These findings reveal previously unappreciated facets of interaction of an invasive bacterium with host cells and a prominent role for Erk1/2 in the control of filopodial dynamics.
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Affiliation(s)
- Stéphane Romero
- Equipe Communication Intercellulaire et Infections Microbiennes, Centre de Recherche Interdisciplinaire en Biologie, Collège de France, 75005 Paris, France
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Lee TF, Lin YL, Huang YT. Kaerophyllin inhibits hepatic stellate cell activation by apoptotic bodies from hepatocytes. Liver Int 2011; 31:618-29. [PMID: 21457435 DOI: 10.1111/j.1478-3231.2011.02485.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND Hepatic stellate cells (HSCs), the key cell type for hepatic fibrosis, become activated and profibrogenic in the presence of hepatocyte apoptotic bodies (ABs). Bupleurum scorzonerifolium (BS), a widely used traditional Chinese herb for liver diseases, was fractionated, and the inhibitory effects of BS extracts on AB-induced HSC migration were screened. The activity-guided fractionation led to a lignan, kaerophyllin. In this study, the anti-fibrotic effects of kaerophyllin were studied in the presence of ABs. METHODS LX-2 cells phagocytosing ultraviolet (UV)-induced HepG2 ABs were investigated by confocal microscopy and flow cytometry. AB-induced HSC activation was evaluated by immunoblotting and real-time PCR analyses. HSC migration was measured by wound-healing assays. RESULTS HepG2 ABs induced LX-2 activation, with the production of collagen I and α-smooth muscle actin, upregulated profibrogenic gene transcriptions and increased NF-κB activity, cell migration and phagocytosis. Kaerophyllin from BS antagonized AB-induced HSC migration and activation. CONCLUSIONS Kaerophyllin inhibited AB-induced LX-2 activation and migration with downregulation of Akt/ERK phosphorylations and NF-κB activity. Our study suggests a novel platform for screening anti-fibrotic compounds with ABs.
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Affiliation(s)
- Ting-Fang Lee
- Institute of Traditional Medicine, National Yang-Ming University, Taipei, Taiwan
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33
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Liu W, Han F, Zhang X. Ran GTPase regulates hemocytic phagocytosis of shrimp by interaction with myosin. J Proteome Res 2009; 8:1198-206. [PMID: 19166347 DOI: 10.1021/pr800840x] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Ran GTPases, one family of small G protein superfamily, have been widely demonstrated to be involved in the transport system between cytoplasm and the nucleus. However, the function of Ran GTPase in immunity remains unclear. In our study, it was found that the Ran GTPase (designated as PjRan) was up-regulated in virus-resistant shrimp, indicating that the PjRan might be implicated in the innate immune system against virus infection. On the basis of protein interactions, it was found that the PjRan interacted with myosin, a crucial protein in the process of phagocytosis to form a protein complex. The RNAi and mRNA assays showed that the PjRan could regulate shrimp hemocytic phagocytosis. Further data evidenced that the depletion of PjRan by RNAi caused a significant increase of virus copies, and the overexpression of PjRan resulted in a significant decrease of virus copies, suggesting that the PjRan participated in the antiviral immunity by regulating phagocytosis. Therefore, our study revealed a completely novel aspect of Ran GTPase in phagocytosis by the direct interaction with the cytoskeleton protein and presented a novel pathway concerning to antiviral immunity, which will help to better understand the molecular events in immune response against virus infection in invertebrates.
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Affiliation(s)
- Weifeng Liu
- The Key Laboratory of Conservation Genetics and Reproductive Biology for Wild Animals of the Ministry of Education and College of Life Sciences, Zhejiang University, Hangzhou 310058, The People's Republic of China
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Differential kinase requirement for enhancement of Fc gammaR-mediated phagocytosis in alveolar macrophages by leukotriene B4 vs. D4. Mol Immunol 2009; 46:1204-11. [PMID: 19223078 DOI: 10.1016/j.molimm.2008.11.024] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Accepted: 11/18/2008] [Indexed: 11/22/2022]
Abstract
In alveolar macrophages, leukotriene (LT) B(4) and cysteinyl LTs (LTC(4), LTD(4) and LTE(4)) both enhance Fc gamma receptor (Fc gammaR)-mediated phagocytosis. In the present study we investigated the role of specific PKC isoforms (PKC-alpha and -delta), the MAP kinases p38 and ERK 1/2, and PI3K in mediating the potentiation of Fc gammaR-mediated phagocytosis induced by addition of leukotrienes to the AMs. It was found that exogenously added LTB(4) and LTD(4) both enhanced PKC-delta and -alpha phosphorylation during Fc gammaR engagement. Studies with isoform-selective inhibitors indicated that exogenous LTB(4) effects were dependent on both PKC-alpha and -delta, while LTD(4) effects were exclusively due to PKC-delta activation. Although both exogenous LTB(4) and LTD(4) enhanced p38 and ERK 1/2 activation, LTB(4) required only ERK 1/2, while LTD(4) required only p38 activation. Activation by both LTs was dependent on PI3K activation. Effects of endogenous LTs on kinase activation were also investigated using selective LT receptor antagonists. Endogenous LTB(4) contributed to Fc gammaR-mediated activation of PKC-alpha, ERK 1/2 and PI3K, while endogenous cysLTs contributes to activation of PKC-delta, p38 and PI3K. Taken together, our data show that the capacities of LTB(4) and LTD(4) to enhance Fc gammaR-mediated phagocytosis reflect their differential activation of specific kinase programs.
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Abstract
The production and deployment of phagocytes are central functions of the hematopoietic system. In the 1950s, radioisotopic studies demonstrated the high production rate and short lifespan of neutrophils and allowed researchers to follow the monocytes as they moved from the marrow through the blood to become tissue macrophages, histiocytes, and dendritic cells. Subsequently, the discovery of the colony-stimulating factors greatly improved understanding the regulation of phagocyte production. The discovery of the microbicidal myeloperoxidase-H2O2-halide system and the importance of NADPH oxidase to the generation of H2O2 also stimulated intense interest in phagocyte disorders. More recent research has focused on membrane receptors and the dynamics of the responses of phagocytes to external factors including immunoglobulins, complement proteins, cytokines, chemokines, integrins, and selectins. Phagocytes express toll-like receptors that aid in the clearance of a wide range of microbial pathogens and their products. Phagocytes are also important sources of pro- and anti-inflammatory cytokines, thus participating in host defenses through a variety of mechanisms. Over the last 50 years, many genetic and molecular disorders of phagocytes have been identified, leading to improved diagnosis and treatment of conditions which predispose patients to the risk of recurrent fevers and infectious diseases.
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Tsai RK, Discher DE. Inhibition of "self" engulfment through deactivation of myosin-II at the phagocytic synapse between human cells. ACTA ACUST UNITED AC 2008; 180:989-1003. [PMID: 18332220 PMCID: PMC2265407 DOI: 10.1083/jcb.200708043] [Citation(s) in RCA: 344] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Phagocytosis of foreign cells or particles by macrophages is a rapid process that is inefficient when faced with “self” cells that display CD47—although signaling mechanisms in self-recognition have remained largely unknown. With human macrophages, we show the phagocytic synapse at cell contacts involves a basal level of actin-driven phagocytosis that, in the absence of species-specific CD47 signaling, is made more efficient by phospho-activated myosin. We use “foreign” sheep red blood cells (RBCs) together with CD47-blocked, antibody-opsonized human RBCs in order to visualize synaptic accumulation of phosphotyrosine, paxillin, F-actin, and the major motor isoform, nonmuscle myosin-IIA. When CD47 is functional, the macrophage counter-receptor and phosphatase-activator SIRPα localizes to the synapse, suppressing accumulation of phosphotyrosine and myosin without affecting F-actin. On both RBCs and microbeads, human CD47 potently inhibits phagocytosis as does direct inhibition of myosin. CD47–SIRPα interaction initiates a dephosphorylation cascade directed in part at phosphotyrosine in myosin. A point mutation turns off this motor's contribution to phagocytosis, suggesting that self-recognition inhibits contractile engulfment.
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Affiliation(s)
- Richard K Tsai
- Biophysical Engineering Laboratory, University of Pennsylvania, Philadelphia, PA 19104, USA
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Luther K, Rohde M, Sturm K, Kotz A, Heesemann J, Ebel F. Characterisation of the phagocytic uptake of Aspergillus fumigatus conidia by macrophages. Microbes Infect 2007; 10:175-84. [PMID: 18248765 DOI: 10.1016/j.micinf.2007.11.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 11/06/2007] [Accepted: 11/08/2007] [Indexed: 11/17/2022]
Abstract
Aspergillus fumigatus is an opportunistic fungal pathogen responsible for severe, life-threatening infections in immunocompromised patients. Airborne conidia are the infectious agent and can reach the lower parts of the respiratory system. In the lung, phagocytes represent the first line of defence. Resident macrophages are able to track down, engulf and kill the invading spores. Phagocytosis of the conidia is therefore a prerequisite for their efficient elimination. Using human and murine macrophages we analysed the phagocytic uptake of A. fumigatus conidia. We found that conidial phagocytosis is an actin-depending process that additionally requires myosin motor, phosphoinositide-3-phosphate kinase and tyrosine kinase activity. Both broad range tyrosine kinase inhibitors and inhibitors that specifically block src kinases had a strong impact on the conidial uptake. Immunofluorescence data demonstrate the recruitment of tyrosine-phosphorylated proteins to the vicinity of engulfed conidia. Uptake of the conidia was accompanied by a strong and local reorganisation of the actin cytoskeleton, whereas no prominent reorganisation was apparent for the microtubules. Both confocal immunofluorescence and electron microscopic data revealed the presence of large ruffle-like structures engaged in the uptake of conidia. This suggests that the internalisation of A. fumigatus spores can be mediated by a process resembling macropinocytosis, which is furthermore supported by the detection of intracellular conidia within spacious vacuoles. Taken together, our data provide new insights into the internalisation of A. fumigatus spores by macrophages, a key process in the early immune defence against an Aspergillus infection.
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Affiliation(s)
- Kathrin Luther
- Max-von-Pettenkofer-Institute, Ludwig-Maximilians-University, Munich, Germany
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38
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Abstract
Prolonged exposure to fluid shear stress alters leukocyte functions associated with the immune response. We examined the initial response of freshly isolated human leukocytes to fluid shear stress under high magnification. Adherent leukocytes exhibit a rapid biomechanical response to physiological levels of fluid shear stress. After passive displacement in the direction of a constant fluid shear stress, adherent leukocytes actively recoil back in the opposite direction of the fluid flow. Recoil is observed within seconds of the applied fluid shear stress. Simultaneously, fluid shear stress induces a stiffening of the cell. The immediate cell displacement in response to a step increase in fluid shear stress is greatly attenuated in subsequent steps compared to the initial fluid shear stress step. Recoil is not mediated by actin polymerization-dependent mechanisms, as cytochalasin D had no effect on this early response. However, stiffening was determined in part by an intact actin cytoskeleton. Inhibiting myosin force generation with ML-7 abolished the recoil and stiffening responses, implicating force generation by myosin as an important contributor to the early leukocyte response to fluid shear stress. This initial shear stress response may be particularly important in facilitating leukocyte attachment under sustained fluid shear stress by the flowing blood in the microcirculation.
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Zelck UE, Gege BE, Schmid S. Specific inhibitors of mitogen-activated protein kinase and PI3-K pathways impair immune responses by hemocytes of trematode intermediate host snails. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2007; 31:321-31. [PMID: 16926049 DOI: 10.1016/j.dci.2006.06.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2006] [Revised: 06/20/2006] [Accepted: 06/21/2006] [Indexed: 05/11/2023]
Abstract
To characterize molecular mechanisms regulating snail cellular immune responses, the contributions of mitogen-activated protein kinases (MAPKs) and phosphatidylinositol 3-kinase (PI3-K) were examined in hemocytes of the trematode intermediate host snails Biomphalaria glabrata and Lymnaea stagnalis. Simultaneous measurement of phagocytosis/encapsulation and H2O2 production by hemocytes in the presence or absence of specific signal transduction inhibitors was used to assess the role of extracellular-signal regulated kinases 1 and 2 (ERK1/2), p38, JNK and PI3-K. Hemocyte spreading was significantly reduced in a dose-dependent manner by the ERK inhibitor, PD098059, and by wortmannin, a potent PI3-K inhibitor. The JNK inhibitor, SP600125, and the p38 kinase inhibitor, SB203580, had no effect on hemocyte spreading. Sheep red blood cell phagocytosis was significantly impaired by PD098059, SP600125, and SB203580. Hydrogen peroxide production during phagocytosis was severely inhibited by PD098059. Additionally, PD098059, but not the other inhibitors, significantly impaired the cellular encapsulation of trematode larvae and H2O2 production during encapsulation. These results suggest that MAPK and PI3-K signal transduction pathways play a pivotal role in the immune responses of snail hemocytes. PI3-K and ERK appear to strongly regulate cell motility. ERK, JNK and p38 contribute to phagocytosis-mediated signal transduction. ERK also play a major role in oxidative burst activation and the encapsulation of trematode larvae by snail hemocytes.
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Affiliation(s)
- Ulrike E Zelck
- Molecular Parasitology Unit, Institute for Tropical Medicine, Wilhelmstr. 27, D-72074 Tuebingen, Germany.
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40
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Suzuki T, Yanai M, Kubo H, Kanda A, Sasaki H, Butler JP. Interaction of non-adherent suspended neutrophils to complement opsonized pathogens: a new assay using optical traps. Cell Res 2006; 16:887-94. [PMID: 17063142 DOI: 10.1038/sj.cr.7310103] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Phagocytosis of opsonized pathogens by circulating non-adherent neutrophils is an essential step in host defense, which when overwhelmed contributes to sepsis. To investigate the role played by ligation of complement receptors CR3 and CR4 in non-adherent neutrophils, we designed a novel assay system utilizing dual optical traps, respectively, holding a suspended unactivated cell and presenting a specific ligand-coated bead to the cell surface. We chose anti-CD18 as an example ligand, mimicking the bacterial opsonizing complement fragment iC3b. Presentation of anti-CD18-coated beads elicited both pseudopodial protrusion and subsequent phagocytosis. This is in sharp contrast to previously reported responses of adherent neutrophils, which phagocytize opsonized particles without pseudopod formation. We used this same new assay to probe actomyosin pathways in the neutrophil's pseudopodial and phagocytic response. Disruption of actin or inhibition of myosin light-chain kinase dose-dependently reduced pseudopod formation and phagocytosis rates. In summary, i) the new dual trap assay can be used to study the responses of suspended neutrophils to a variety of ligands, and ii) in a first application of this technique, we found that local ligation of CR3/4 in unactivated neutrophils in suspension induces pseudopod formation and phagocytosis at that site, and that these events occur via an actomyosin-dependent pathway.
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Affiliation(s)
- Tomoko Suzuki
- Department of Geriatric and Respiratory Medicine, Tohoku University School of Medicine, Sendai 980-8574, Japan
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41
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Jehle AW, Gardai SJ, Li S, Linsel-Nitschke P, Morimoto K, Janssen WJ, Vandivier RW, Wang N, Greenberg S, Dale BM, Qin C, Henson PM, Tall AR. ATP-binding cassette transporter A7 enhances phagocytosis of apoptotic cells and associated ERK signaling in macrophages. ACTA ACUST UNITED AC 2006; 174:547-56. [PMID: 16908670 PMCID: PMC2064260 DOI: 10.1083/jcb.200601030] [Citation(s) in RCA: 155] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The mammalian ATP-binding cassette transporters A1 and A7 (ABCA1 and -A7) show sequence similarity to CED-7, a Caenorhabditis elegans gene that mediates the clearance of apoptotic cells. Using RNA interference or gene targeting, we show that knock down of macrophage ABCA7 but not -A1 results in defective engulfment of apoptotic cells. In response to apoptotic cells, ABCA7 moves to the macrophage cell surface and colocalizes with the low-density lipoprotein receptor–related protein 1 (LRP1) in phagocytic cups. The cell surface localization of ABCA7 and LRP1 is defective in ABCA7-deficient cells. C1q is an opsonin of apoptotic cells that acts via phagocyte LRP1 to induce extracellular signal–regulated kinase (ERK) signaling. We show that ERK signaling is required for phagocytosis of apoptotic cells and that ERK phosphorylation in response to apoptotic cells or C1q is defective in ABCA7-deficient cells. These studies reveal a major role of ABCA7 and not -A1 in the clearance of apoptotic cells and therefore suggest that ABCA7 is an authentic orthologue of CED-7.
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Affiliation(s)
- Andreas W Jehle
- Department of Medicine, Columbia University, New York, NY 10032, USA.
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42
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Nakamae-Akahori M, Kato T, Masuda S, Sakamoto E, Kutsuna H, Hato F, Nishizawa Y, Hino M, Kitagawa S. Enhanced neutrophil motility by granulocyte colony-stimulating factor: the role of extracellular signal-regulated kinase and phosphatidylinositol 3-kinase. Immunology 2006; 119:393-403. [PMID: 16903868 PMCID: PMC1819568 DOI: 10.1111/j.1365-2567.2006.02448.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The effect of granulocyte colony-stimulating factor (G-CSF) on human neutrophil motility was studied using videomicroscopy. Stimulation of neutrophils with G-CSF resulted in enhanced motility with morphological change and increased adherence. Enhanced neutrophil motility was detected within 3-5 min after G-CSF stimulation, reached a maximum at 10 min, and was sustained for approximately 35 min. The maximum migration rate was 84.4 +/- 2.9 microm/5 min. A study using the Boyden chamber method revealed that G-CSF-stimulated neutrophils exhibited random migration but not chemotaxis. Enhanced neutrophil motility and morphological change were inhibited by MEK [mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) kinase] inhibitors (PD98059 and U0126), and a phosphatidylinositol 3-kinase (PI3K) inhibitor (wortmannin), but not by a p38 MAPK inhibitor (SB203580). These findings are consistent with the fact that G-CSF selectively activates MEK/ERK and PI3K, but not p38, in neutrophils. MEK/ERK activation was associated with G-CSF-induced redistribution of F-actin and phosphorylated myosin light chain. Enhanced neutrophil motility was observed even in the presence of neutralizing anti-CD18 antibody, which prevented cell adherence. These findings indicate that G-CSF induces human neutrophil migration via activation of MEK/ERK and PI3K.
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Affiliation(s)
- Mika Nakamae-Akahori
- Department of Physiology, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
| | - Takayuki Kato
- Department of Physiology, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
| | - Sayuri Masuda
- Department of Physiology, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
| | - Erina Sakamoto
- Department of Physiology, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
| | - Haruo Kutsuna
- Department of Physiology, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
| | - Fumihiko Hato
- Department of Physiology, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
| | - Yoshiki Nishizawa
- Department of Medicine, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
| | - Masayuki Hino
- Department of Clinical Haematology, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
| | - Seiichi Kitagawa
- Department of Physiology, Osaka City University Graduate School of Medicine, Asahi-machiAbeno-ku, Osaka, Japan
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43
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Bessard A, Coutant A, Rescan C, Ezan F, Frémin C, Courselaud B, Ilyin G, Baffet G. An MLCK-dependent window in late G1 controls S phase entry of proliferating rodent hepatocytes via ERK-p70S6K pathway. Hepatology 2006; 44:152-63. [PMID: 16799973 DOI: 10.1002/hep.21222] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We show that MLCK (myosin light chain kinase) plays a key role in cell cycle progression of hepatocytes: either chemical inhibitor ML7 or RNA interference led to blockade of cyclin D1 expression and DNA replication, providing evidence that MLCK regulated S phase entry. Conversely, inhibition of RhoK by specific inhibitor Y27632 or RhoK dominant-negative vector did not influence progression in late G1 and S phase entry. Inhibition of either MLCK or RhoK did not block ERK1/2 phosphorylation, whereas MLCK regulated ERK2-dependent p70S6K activation. In addition, DNA synthesis was reduced in hepatocytes treated with p70S6K siRNA, demonstrating the key role played by the kinase in S phase entry. Interestingly, after the G1/S transition, DNA replication in S phase was no longer dependent on MLCK activity. We strengthened this result by ex vivo experiments and evidenced an MLCK-dependent window in late G1 phase of regenerating liver after two-thirds partial hepatectomy. In conclusion, our results underline an MLCK-dependent restriction point in G1/S transition, occurring downstream of ERK2 through the regulation of p70S6K activation, and highlighting a new signaling pathway critical for hepatocyte proliferation.
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Affiliation(s)
- Anne Bessard
- INSERM U522, Unité de Recherches Hépatologiques; IFR 140; Université de Rennes1, Rennes, France
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44
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Abstract
The microvascular endothelial cell monolayer localized at the critical interface between the blood and vessel wall has the vital functions of regulating tissue fluid balance and supplying the essential nutrients needed for the survival of the organism. The endothelial cell is an exquisite “sensor” that responds to diverse signals generated in the blood, subendothelium, and interacting cells. The endothelial cell is able to dynamically regulate its paracellular and transcellular pathways for transport of plasma proteins, solutes, and liquid. The semipermeable characteristic of the endothelium (which distinguishes it from the epithelium) is crucial for establishing the transendothelial protein gradient (the colloid osmotic gradient) required for tissue fluid homeostasis. Interendothelial junctions comprise a complex array of proteins in series with the extracellular matrix constituents and serve to limit the transport of albumin and other plasma proteins by the paracellular pathway. This pathway is highly regulated by the activation of specific extrinsic and intrinsic signaling pathways. Recent evidence has also highlighted the importance of the heretofore enigmatic transcellular pathway in mediating albumin transport via transcytosis. Caveolae, the vesicular carriers filled with receptor-bound and unbound free solutes, have been shown to shuttle between the vascular and extravascular spaces depositing their contents outside the cell. This review summarizes and analyzes the recent data from genetic, physiological, cellular, and morphological studies that have addressed the signaling mechanisms involved in the regulation of both the paracellular and transcellular transport pathways.
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Affiliation(s)
- Dolly Mehta
- Center of Lung and Vascular Biology, Dept. of Pharmacology (M/C 868), University of Illinois, 835 S. Wolcott Avenue, Chicago, IL 60612, USA
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45
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Abstract
Phagocytosis is the mechanism of internalization used by specialized cells such as macrophages, dendritic cells, and neutrophils to internalize, degrade, and eventually present peptides derived from particulate antigens. The phagocytic process comprises several sequential and complex events initiated by the recognition ofligands on the surface of the particles by specific receptors on the surface of the phagocytic cells. Receptor clustering at the attachment site generates a phagocytic signal that in turn leads to local polymerization of actin filaments and to particle internalization. Depending on the particles and receptors involved, it appears that the structures and mechanisms associated with particle ingestion are diverse. However, work during the past few years has highlighted the importance of small GTP-binding proteins of the Rho family in various types of phagocytosis. As reviewed here, Rho family GTPases, their activators, and their downstream effectors control the local reorganization of the actin cytoskeleton beneath bound particles.
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Affiliation(s)
- F Niedergang
- Membrane and Cytoskeleton Dynamics Group, Institut Curie, CNRS UMR144, 75248 Paris, France
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46
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Mansfield PJ, Hinkovska-Galcheva V, Borofsky MS, Shayman JA, Boxer LA. Phagocytic signaling molecules in lipid rafts of COS-1 cells transfected with FcgammaRIIA. Biochem Biophys Res Commun 2005; 331:132-8. [PMID: 15845369 DOI: 10.1016/j.bbrc.2005.02.191] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Indexed: 11/28/2022]
Abstract
COS-1 cells bearing FcgammaRIIA were used as a model to demonstrate co-localization of several enzymes previously shown to regulate neutrophil phagocytosis. In COS-1 cells, phospholipase D (PLD) in the membrane fraction was activated during phagocytosis. PLD was found almost exclusively in lipid rafts, along with RhoA and ARF1. Protein kinase C-delta (PKCdelta) and Raf-1 translocated to lipid rafts. In neutrophils, ceramide levels increase during phagocytosis, indicating that FcgammaRIIA engagement initiates ceramide generation. Applying this model, we transfected COS-1 cells with FcgammaRIIA that had been mutated in the ITAM region, rendering them unable to ingest particles. When the mutant receptors were engaged, ceramide was generated and MAPK was activated normally, thus these processes did not require actual ingestion of particles. These results indicate that signaling proteins for phagocytosis are either constitutively present in, or are recruited to, lipid rafts where they are readily available to activate one another.
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Affiliation(s)
- Pamela J Mansfield
- Department of Pediatrics, Division of Hematology/Oncology, University of Michigan, Ann Arbor, MI 48109, USA
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47
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Viala E, Pouysségur J. Regulation of tumor cell motility by ERK mitogen-activated protein kinases. Ann N Y Acad Sci 2005; 1030:208-18. [PMID: 15659800 DOI: 10.1196/annals.1329.027] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Metastasis is the main cause of human cancer deaths, and cell motility is one key component of the process of metastasis. The ERK mitogen-activated protein kinase (MAPK) signaling pathway is probably one of the most commonly activated in malignant human cancers. We describe the molecular mechanisms by which ERK MAPK signaling regulates cell motility and its importance for cancer cell dissemination.
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Affiliation(s)
- Emmanuel Viala
- Institute of Signaling Developmental Biology and Cancer, Centre National de la Recherche Scientifique Unité Mixte de Recherche 6543, Centre Antoine Lacassagne, 33 avenue de Valombrose, 06189 Nice, France.
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48
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Canobbio I, Noris P, Pecci A, Balduini A, Balduini CL, Torti M. Altered cytoskeleton organization in platelets from patients with MYH9-related disease. J Thromb Haemost 2005; 3:1026-35. [PMID: 15869600 DOI: 10.1111/j.1538-7836.2005.01244.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
MYH9-related disease (MYH9-RD) is an autosomal dominant disorder deriving from mutations in the MYH9 gene encoding for the heavy chain of non-muscle myosin IIA, and characterized by thrombocytopenia and giant platelets. Isoform IIA of myosin is the only one expressed in platelets, but the possibility that MYH9 mutations affect the organization of contractile structures in these blood elements has never been investigated. In this work we have analyzed the composition and the agonist-induced reorganization of the platelet cytoskeleton from seven MYH9-RD patients belonging to four different families. We found that an increased amount of myosin was constitutively associated with actin in the cytoskeleton of resting MYH9-RD platelets. Upon platelet stimulation, an impaired increase in the total cytoskeletal proteins was observed. Moreover, selected membrane glycoproteins, tyrosine kinases, and small GTPases failed to interact with the cytoskeleton in agonist-stimulated MYH9-RD platelets. These results demonstrate for the first time that mutations of MYH9 result in an alteration of the composition and agonist-induced reorganization of the platelet cytoskeleton. We suggest that these abnormalities may represent the biochemical basis for the previously reported functional alterations of MYH9-RD platelets, and for the abnormal platelet formation from megakaryocytes, resulting in thrombocytopenia and giant platelets.
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Affiliation(s)
- I Canobbio
- Centre of Excellence for Applied Biology, Department of Biochemistry, University of Pavia, Pavia, Italy
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49
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Okazawa H, Motegi SI, Ohyama N, Ohnishi H, Tomizawa T, Kaneko Y, Oldenborg PA, Ishikawa O, Matozaki T. Negative regulation of phagocytosis in macrophages by the CD47-SHPS-1 system. THE JOURNAL OF IMMUNOLOGY 2005; 174:2004-11. [PMID: 15699129 DOI: 10.4049/jimmunol.174.4.2004] [Citation(s) in RCA: 222] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Src homology 2 domain-containing protein tyrosine phosphatase (SHP) substrate-1 (SHPS-1) is a transmembrane protein that is expressed predominantly in macrophages. Its extracellular region interacts with the transmembrane ligand CD47 expressed on the surface of adjacent cells, and its cytoplasmic region binds the protein tyrosine phosphatases SHP-1 and SHP-2. Phagocytosis of IgG- or complement-opsonized RBCs by peritoneal macrophages derived from mice that express a mutant SHPS-1 protein that lacks most of the cytoplasmic region was markedly enhanced compared with that apparent with wild-type macrophages. This effect was not observed either with CD47-deficient RBCs as the phagocytic target or in the presence of blocking Abs to SHPS-1. Depletion of SHPS-1 from wild-type macrophages by RNA interference also promoted FcgammaR-mediated phagocytosis of wild-type RBCs. Ligation of SHPS-1 on macrophages by CD47 on RBCs promoted tyrosine phosphorylation of SHPS-1 and its association with SHP-1, whereas tyrosine phosphorylation of SHPS-1 was markedly reduced in response to cross-linking of FcgammaRs. Treatment with inhibitors of PI3K or of Syk, but not with those of MEK or Src family kinases, abolished the enhancement of FcgammaR-mediated phagocytosis apparent in macrophages from SHPS-1 mutant mice. In contrast, FcgammaR-mediated tyrosine phosphorylation of Syk, Cbl, or the gamma subunit of FcR was similar in macrophages from wild-type and SHPS-1 mutant mice. These results suggest that ligation of SHPS-1 on macrophages by CD47 promotes the tyrosine phosphorylation of SHPS-1 and thereby prevents the FcgammaR-mediated disruption of the SHPS-1-SHP-1 complex, resulting in inhibition of phagocytosis. The inhibition of phagocytosis by the SHPS-1-SHP-1 complex may be mediated at the level of Syk or PI3K signaling.
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MESH Headings
- Animals
- Antibodies, Blocking/pharmacology
- Antibodies, Monoclonal/pharmacology
- Antigens, CD/genetics
- Antigens, CD/immunology
- Antigens, CD/metabolism
- Antigens, CD/physiology
- Antigens, Differentiation/genetics
- Antigens, Differentiation/immunology
- Antigens, Differentiation/metabolism
- CD47 Antigen
- Complement C3b/metabolism
- Cross-Linking Reagents/metabolism
- Down-Regulation/genetics
- Down-Regulation/immunology
- Enzyme Precursors/antagonists & inhibitors
- Erythrocytes/immunology
- Erythrocytes/metabolism
- Immunoglobulin G/metabolism
- Intracellular Signaling Peptides and Proteins
- Macrophages, Peritoneal/enzymology
- Macrophages, Peritoneal/immunology
- Macrophages, Peritoneal/metabolism
- Membrane Glycoproteins/antagonists & inhibitors
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/immunology
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Neural Cell Adhesion Molecule L1/antagonists & inhibitors
- Neural Cell Adhesion Molecule L1/genetics
- Neural Cell Adhesion Molecule L1/immunology
- Neural Cell Adhesion Molecule L1/metabolism
- Opsonin Proteins/metabolism
- Phagocytosis/genetics
- Phagocytosis/immunology
- Phosphoinositide-3 Kinase Inhibitors
- Phosphorylation
- Protein-Tyrosine Kinases/antagonists & inhibitors
- RNA, Small Interfering/pharmacology
- Receptors, IgG/metabolism
- Receptors, IgG/physiology
- Receptors, Immunologic/antagonists & inhibitors
- Receptors, Immunologic/genetics
- Receptors, Immunologic/immunology
- Receptors, Immunologic/metabolism
- Signal Transduction/genetics
- Signal Transduction/immunology
- Syk Kinase
- Tyrosine/metabolism
- src-Family Kinases/antagonists & inhibitors
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Affiliation(s)
- Hideki Okazawa
- Biosignal Research Center, Institute for Molecular and Cellular Regulation, and Department of Dermatology, Graduate School of Medicine, Gunma University, Showa-Machi, Maebashi, Gunma, Japan
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50
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Coughlin MF, Schmid-Schönbein GW. Pseudopod projection and cell spreading of passive leukocytes in response to fluid shear stress. Biophys J 2005; 87:2035-42. [PMID: 15345579 PMCID: PMC1304606 DOI: 10.1529/biophysj.104.042192] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recent evidence suggests that circulating leukocytes respond to physiological levels of fluid shear stress. This study was designed to examine the shear stress response of individual leukocytes adhering passively to a glass surface. Human leukocytes were exposed to a step fluid shear stress with amplitude between 0.2 and 4 dyn/cm(2) and duration between 1 and 20 min. The response of the cells was determined in the form of projected cell area measurements by high-resolution observation before, during, and after fluid shear application. All cells selected initially had a round morphology. After application of fluid shear many cells projected pseudopodia and spread on the glass surface. The number of leukocytes responding with pseudopod projection and the extent of cell spreading increased with increasing amplitude and duration of fluid shear stress. Pseudopod projection after exposure to a step fluid shear occurs following a delay that is insensitive to the shear stress amplitude and duration. Leukocytes that did not project pseudopodia and spread in response to low shear stress could be shown to respond to a second shear step of higher amplitude. The spreading response requires an intact actin network and activated myosin molecules. Depleting the cell glycocalyx with protease treatment enhances the spreading response in sheared leukocytes. These results indicate that passive leukocytes respond to fluid shear stress with active pseudopod projection and cell spreading. This behavior may contribute to cell spreading on endothelium and other cells as well as to transendothelial migration of leukocytes in the microcirculation.
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Affiliation(s)
- Mark F Coughlin
- Department of Bioengineering, The Whitaker Institute for Biomedical Engineering, University of California, San Diego, La Jolla, California 92093-0412, USA.
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