1
|
Kara A, Ozkanlar S. Blockade of P2X7 receptor-mediated purinergic signaling with A438079 protects against LPS-induced liver injury in rats. J Biochem Mol Toxicol 2023; 37:e23443. [PMID: 37365769 DOI: 10.1002/jbt.23443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 02/05/2023] [Accepted: 06/14/2023] [Indexed: 06/28/2023]
Abstract
The study aimed to investigate the hepatoprotective effects of purinergic receptor (P2X7R) antagonism by A438079 in liver damage. An experimental model of inflammation was performed by intraperitoneal (i.p.) lipopolysaccharide (LPS) administration in the rat. The groups were Control, A438079, dimethyl sulfoxide (DMSO), LPS, LPS + DMSO, and LPS + A438079. Following LPS (8 mg/kg) injection, A438079 (15 mg/kg) and DMSO (0.1 mL) were administrated (i.p) in the study groups. The blood and the liver tissues were removed for histological, biochemical, and western blot analyses. In the biochemical analysis, serum aspartate transaminase (AST) and alanine transaminase (ALT) concentrations, the tissue glutathione (GSH) level, and superoxide dismutase (SOD) activity dramatically decreased and malondialdehyde (MDA) level increased in the LPS and LPS + DMSO groups compared to the LPS + A438079 group. In the histological analysis, severe sinusoidal dilatation, necrotic hepatocytes, and inflammatory cell infiltration were observed in the LPS and LPS + DMSO groups while these effects were lessened in the LPS + A438079 group. The relative protein expression levels of P2X7R, Nf-kB-p65, IL-6, and Caspase-3 were significantly higher in the LPS and the LPS + DMSO groups than in the LPS + A438079 group. On the other hand, these protein expressions were considerably lower in the Control, A438079, and DMSO groups compared to the LPS + A438079 group. In addition, Bcl-2 protein expression was significantly lower in the LPS and the LPS + DMSO groups and higher in the LPS + A438079 group compared to the other groups. The protective effect of A438079 against LPS-induced hepatic inflammation may be related to P2X7R antagonism, inflammatory mediators, and apoptotic cell death.
Collapse
Affiliation(s)
- Adem Kara
- Department of Molecular Biology and Genetics, Faculty of Science, Erzurum Technical University, Erzurum, Turkey
| | - Seckin Ozkanlar
- Department of Biochemistry, Faculty of Veterinary Medicine, Atatürk University, Erzurum, Turkey
| |
Collapse
|
2
|
Elhage A, Turner RJ, Cuthbertson P, Watson D, Sluyter R. Preparation of the Murine Anti-Human P2X7 Receptor Monoclonal Antibody (Clone L4). METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2022; 2510:77-98. [PMID: 35776321 DOI: 10.1007/978-1-0716-2384-8_5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The murine anti-human P2X7 receptor monoclonal antibody (mAb) (clone L4) has been used to study the expression and function of the P2X7 receptor on primary leukocytes, keratinocytes, osteoblasts and neuronal cells, as well as various cell lines. This antibody has also been used to characterize polymorphic variants and isoforms of the P2RX7 gene and P2X7 site-directed mutations, and to identify molecules coassociated with P2X7 in the plasma membrane. This chapter describes the maintenance and cryopreservation of the L4 hybridoma cell line, as well as the generation of tissue culture supernatant containing the anti-human P2X7 mAb, and its subsequent purification by Protein A chromatography and conjugation to DyLight™ 488. Moreover, this chapter describes flow cytometric assays to assess the blocking activity and binding of the anti-human P2X7 mAb against P2X7 on human RPMI 8226 multiple myeloma cells.
Collapse
Affiliation(s)
- Amal Elhage
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Ross J Turner
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
- Illawarra Cancer Care Centre, Wollongong Hospital, Wollongong, NSW, Australia
| | - Peter Cuthbertson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Debbie Watson
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia
| | - Ronald Sluyter
- Illawarra Health and Medical Research Institute, Wollongong, NSW, Australia.
- Molecular Horizons and School of Chemistry and Molecular Bioscience, University of Wollongong, Wollongong, NSW, Australia.
| |
Collapse
|
3
|
Wang Z, Ahmed S, Labib M, Wang H, Hu X, Wei J, Yao Y, Moffat J, Sargent EH, Kelley SO. Efficient recovery of potent tumour-infiltrating lymphocytes through quantitative immunomagnetic cell sorting. Nat Biomed Eng 2022; 6:108-117. [PMID: 35087171 DOI: 10.1038/s41551-021-00820-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 09/30/2021] [Indexed: 12/14/2022]
Abstract
Adoptive cell therapies require the recovery and expansion of highly potent tumour-infiltrating lymphocytes (TILs). However, TILs in tumours are rare and difficult to isolate efficiently, which hinders the optimization of therapeutic potency and dose. Here we show that a configurable microfluidic device can efficiently recover potent TILs from solid tumours by leveraging specific expression levels of target cell-surface markers. The device, which is sandwiched by permanent magnets, balances magnetic forces and fluidic drag forces to sort cells labelled with magnetic nanoparticles conjugated with antibodies for the target markers. Compared with conventional cell sorting, immunomagnetic cell sorting recovered up to 30-fold higher numbers of TILs, and the higher levels and diversity of the recovered TILs accelerated TIL expansion and enhanced their therapeutic potency. Immunomagnetic cell sorting also allowed us to identify and isolate potent TIL subpopulations, in particular TILs with moderate levels of CD39 (a marker of T-cell reactivity to tumours and T-cell exhaustion), which we found are tumour-specific, self-renewable and essential for the long-term success of adoptive cell therapies.
Collapse
Affiliation(s)
- Zongjie Wang
- The Edward S. Rogers Sr Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario, Canada.,Institute for Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Sharif Ahmed
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Mahmoud Labib
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Hansen Wang
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Xiyue Hu
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
| | - Jiarun Wei
- Department of Molecular Genetics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.,Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
| | - Yuxi Yao
- Department of Molecular Genetics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.,Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
| | - Jason Moffat
- Department of Molecular Genetics, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.,Terrence Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario, Canada
| | - Edward H Sargent
- The Edward S. Rogers Sr Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Shana O Kelley
- Institute for Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada. .,Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada. .,Department of Biochemistry, Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada. .,Department of Chemistry, Northwestern University, Evanston, IL, USA. .,Department of Biomedical Engineering, Northwestern University, Evanston, IL, USA.
| |
Collapse
|
4
|
Sáez PJ, Vargas P, Shoji KF, Harcha PA, Lennon-Duménil AM, Sáez JC. ATP promotes the fast migration of dendritic cells through the activity of pannexin 1 channels and P2X 7 receptors. Sci Signal 2017; 10:10/506/eaah7107. [PMID: 29162744 DOI: 10.1126/scisignal.aah7107] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Upon its release from injured cells, such as infected, transformed, inflamed, or necrotic cells, extracellular adenosine-5'-triphosphate (ATP) acts as a danger signal that recruits phagocytes, such as neutrophils, macrophages, and dendritic cells (DCs), to the site of injury. The sensing of extracellular ATP occurs through purinergic (P2) receptors. We investigated the cellular mechanisms linking purinergic signaling to DC motility. We found that ATP stimulated fast DC motility through an autocrine signaling loop, which was initiated by the activation of P2X7 receptors and further amplified by pannexin 1 (Panx1) channels. Upon stimulation of the P2X7 receptor by ATP, Panx1 contributed to fast DC motility by increasing the permeability of the plasma membrane, which resulted in supplementary ATP release. In the absence of Panx1, DCs failed to increase their speed of migration in response to ATP, despite exhibiting a normal P2X7 receptor-mediated Ca2+ response. In addition to DC migration, Panx1 channel- and P2X7 receptor-dependent signaling was further required to stimulate the reorganization of the actin cytoskeleton. In vivo, functional Panx1 channels were required for the homing of DCs to lymph nodes, although they were dispensable for DC maturation. These data suggest that P2X7 receptors and Panx1 channels are crucial players in the regulation of DC migration to endogenous danger signals.
Collapse
Affiliation(s)
- Pablo J Sáez
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 6513677, Chile. .,INSERM U932 Immunité et Cancer, Institut Curie, Paris Sciences et Lettres (PSL) Research University, 12 Rue Lhomond, Paris 75005, France
| | - Pablo Vargas
- INSERM U932 Immunité et Cancer, Institut Curie, Paris Sciences et Lettres (PSL) Research University, 12 Rue Lhomond, Paris 75005, France.,CNRS UMR144, Institut Curie, PSL Research University, 12 Rue Lhomond, Paris 75005, France
| | - Kenji F Shoji
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 6513677, Chile
| | - Paloma A Harcha
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 6513677, Chile.,Instituto Milenio, Centro Interdisciplinario de Neurociencias de Valparaíso, Valparaíso 2360103, Chile
| | - Ana-María Lennon-Duménil
- INSERM U932 Immunité et Cancer, Institut Curie, Paris Sciences et Lettres (PSL) Research University, 12 Rue Lhomond, Paris 75005, France.
| | - Juan C Sáez
- Departamento de Fisiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 6513677, Chile. .,Instituto Milenio, Centro Interdisciplinario de Neurociencias de Valparaíso, Valparaíso 2360103, Chile
| |
Collapse
|
5
|
Metabolites: deciphering the molecular language between DCs and their environment. Semin Immunopathol 2016; 39:177-198. [PMID: 27921148 DOI: 10.1007/s00281-016-0609-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 11/14/2016] [Indexed: 02/07/2023]
Abstract
Dendritic cells (DCs) determine the outcome of the immune response based on signals they receive from the environment. Presentation of antigen under various contexts can lead to activation and differentiation of T cells for immunity or dampening of immune responses by establishing tolerance, primarily through the priming of regulatory T cells. Infections, inflammation and normal cellular interactions shape DC responses through direct contact or via cytokine signaling. Although it is widely accepted that DCs sense microbial components through pattern recognition receptors (PRRs), increasing evidence advocates for the existence of a set of signals that can profoundly shape DC function via PRR-independent pathways. This diverse group of host- or commensal-derived metabolites represents a newly appreciated code from which DCs can interpret environmental cues. In this review, we discuss the existing information on the effect of some of the most studied metabolites on DC function, together with the implications this may have in immune-mediated diseases.
Collapse
|
6
|
Takenaka MC, Robson S, Quintana FJ. Regulation of the T Cell Response by CD39. Trends Immunol 2016; 37:427-439. [PMID: 27236363 DOI: 10.1016/j.it.2016.04.009] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 04/22/2016] [Accepted: 04/25/2016] [Indexed: 12/22/2022]
Abstract
The ectonucleoside triphosphate diphosphohydrolase 1 (ENTPD1, or CD39) catalyzes the phosphohydrolysis of extracellular ATP (eATP) and ADP (eADP) released under conditions of inflammatory stress and cell injury. CD39 generates AMP, which is in turn used by the ecto-5'-nucleotidase CD73 to synthesize adenosine. These ectonucleotidases have a major impact on the dynamic equilibrium of proinflammatory eATP and ADP nucleotides versus immunosuppressive adenosine nucleosides. Indeed, CD39 plays a dominant role in the purinergic regulation of inflammation and the immune response because its expression is influenced by genetic and environmental factors. We review the specific role of CD39 in the kinetic regulation of cellular immune responses in the evolution of disease. We focus on the effects of CD39 on T cells and explore potential clinical applications in autoimmunity, chronic infections, and cancer.
Collapse
Affiliation(s)
- Maisa C Takenaka
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Simon Robson
- Divisions of Gastroenterology, Hepatology, and Transplantation, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
| | - Francisco J Quintana
- Ann Romney Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA; Broad Institute of Massachusetts Institute of Technology (MIT) and Harvard, Cambridge, MA, USA.
| |
Collapse
|
7
|
Galam L, Rajan A, Failla A, Soundararajan R, Lockey RF, Kolliputi N. Deletion of P2X7 attenuates hyperoxia-induced acute lung injury via inflammasome suppression. Am J Physiol Lung Cell Mol Physiol 2016; 310:L572-81. [PMID: 26747786 DOI: 10.1152/ajplung.00417.2015] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 01/05/2016] [Indexed: 12/13/2022] Open
Abstract
Increasing evidence shows that hyperoxia is a serious complication of oxygen therapy in acutely ill patients that causes excessive production of free radicals leading to hyperoxia-induced acute lung injury (HALI). Our previous studies have shown that P2X7 receptor activation is required for inflammasome activation during HALI. However, the role of P2X7 in HALI is unclear. The main aim of this study was to determine the effect of P2X7 receptor gene deletion on HALI. Wild-type (WT) and P2X7 knockout (P2X7 KO) mice were exposed to 100% O2 for 72 h. P2X7 KO mice treated with hyperoxia had enhanced survival in 100% O2 compared with the WT mice. Hyperoxia-induced recruitment of inflammatory cells and elevation of IL-1β, TNF-α, monocyte chemoattractant protein-1, and IL-6 levels were attenuated in P2X7 KO mice. P2X7 deletion decreased lung edema and alveolar protein content, which are associated with enhanced alveolar fluid clearance. In addition, activation of the inflammasome was suppressed in P2X7-deficient alveolar macrophages and was associated with suppression of IL-1β release. Furthermore, P2X7-deficient alveolar macrophage in type II alveolar epithelial cells (AECs) coculture model abolished protein permeability across mouse type II AEC monolayers. Deletion of P2X7 does not lead to a decrease in epithelial sodium channel expression in cocultures of alveolar macrophages and type II AECs. Taken together, these findings show that deletion of P2X7 is a protective factor and therapeutic target for the amelioration of hyperoxia-induced lung injury.
Collapse
Affiliation(s)
- Lakshmi Galam
- Division of Allergy and Immunology, Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Ashna Rajan
- Division of Allergy and Immunology, Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Athena Failla
- Division of Allergy and Immunology, Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Ramani Soundararajan
- Division of Allergy and Immunology, Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Richard F Lockey
- Division of Allergy and Immunology, Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| | - Narasaiah Kolliputi
- Division of Allergy and Immunology, Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida
| |
Collapse
|
8
|
Post-translational allosteric activation of the P2X7 receptor through glycosaminoglycan chains of CD44 proteoglycans. Cell Death Discov 2015; 1:15005. [PMID: 27551441 PMCID: PMC4979527 DOI: 10.1038/cddiscovery.2015.5] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 06/05/2015] [Indexed: 12/21/2022] Open
Abstract
Here, we present evidence for the positive allosteric modulation of the P2X7 receptor through glycosaminoglycans (GAGs) in CHO (cell line derived from the ovary of the Chinese hamster) cells. The marked potentiation of P2X7 activity through GAGs in the presence of non-saturating agonists concentrations was evident with the endogenous expression of the receptor in CHO cells. The presence of GAGs on the surface of CHO cells greatly increased the sensitivity to adenosine 5'-triphosphate and changed the main P2X7 receptor kinetic parameters EC50, Hill coefficient and E max. GAGs decreased the allosteric inhibition of P2X7 receptor through Mg(2+). GAGs activated P2X7 receptor-mediated cytoplasmic Ca(2+) influx and pore formation. Consequently, wild-type CHO-K1 cells were 2.5-fold more sensitive to cell death induced through P2X7 agonists than mutant CHO-745 cells defective in GAGs biosynthesis. In the present study, we provide the first evidence that the P2X7 receptor interacts with CD44 on the CHO-K1 cell surface. Thus, these data demonstrated that GAGs positively modulate the P2X7 receptor, and sCD44 is a part of a regulatory positive feedback loop linking P2X7 receptor activation for the intracellular response mediated through P2X7 receptor stimulation.
Collapse
|
9
|
Wang S, Zhao J, Wang H, Liang Y, Yang N, Huang Y. Blockage of P2X7 attenuates acute lung injury in mice by inhibiting NLRP3 inflammasome. Int Immunopharmacol 2015; 27:38-45. [PMID: 25937482 PMCID: PMC7185518 DOI: 10.1016/j.intimp.2015.04.035] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 04/15/2015] [Accepted: 04/16/2015] [Indexed: 11/19/2022]
Abstract
NLRP3 inflammasome is engaged in the inflammatory response during acute lung injury (ALI). Purinergic receptor P2X7 has been reported to be upstream of NLRP3 activation. However, the therapeutic implication of P2X7 in ALI remains to be explored. The present study used lipopolysaccharide (LPS)-induced mouse model to investigate the therapeutic potential of P2X7 blockage in ALI. Our results showed that P2X7/NLRP3 inflammasome pathway was significantly upregulated in the lungs of ALI mice as compared with control mice. P2X7 antagonist A438079 suppressed NLRP3/ASC/caspase 1 activation, production of IL-1β, IL-17A and IFN-γ and neutrophil infiltration but not the production of IL-10, resulting in a significant amelioration of lung injury. Moreover, blockage of P2X7 significantly inhibited NLRP3 inflammasome activation and IL-1β production in bone marrow derived macrophages. Similar results were obtained using another P2X7 inhibitor brilliant blue G (BBG) in vivo. Thus, pharmacological blockage of P2X7/NLRP3 pathway can be considered as a potential therapeutic strategy in patients with ALI.
Collapse
Affiliation(s)
- Shuang Wang
- Department of Rheumatology, First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Road II, Guangzhou, China
| | - Jijun Zhao
- Department of Rheumatology, First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Road II, Guangzhou, China
| | - Hongyue Wang
- Department of Rheumatology, First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Road II, Guangzhou, China
| | - Yingjie Liang
- Department of Pathology, First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Road II, Guangzhou, China
| | - Niansheng Yang
- Department of Rheumatology, First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Road II, Guangzhou, China
| | - Yuefang Huang
- Department of Pediatrics, First Affiliated Hospital, Sun Yat-sen University, 58 Zhongshan Road II, Guangzhou, China.
| |
Collapse
|
10
|
Kang TB, Yang SH, Toth B, Kovalenko A, Wallach D. Activation of the NLRP3 inflammasome by proteins that signal for necroptosis. Methods Enzymol 2015; 545:67-81. [PMID: 25065886 DOI: 10.1016/b978-0-12-801430-1.00003-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Necroptosis-a form of programmed necrotic cell death-and its resulting release of damage-associated molecular patterns (DAMPs) are believed to participate in the triggering of inflammatory processes. To assess the relative contribution of this cell death mode to inflammation, we need to know what other cellular effects can be exerted by molecules shown to trigger necrotic death, and the extent to which those effects might themselves contribute to inflammation. Here, we describe the technical approaches that have been applied to assess the impact of the main signaling molecules known to mediate activation of necroptosis upon generation of inflammatory cytokines in LPS-treated mouse bone marrow-derived dendritic cells. The findings obtained by this assessment indicated that signaling molecules known to initiate necroptosis can also initiate activation of the NLRP3 inflammasome, thereby inducing inflammation independently of cell death by triggering the generation of proinflammatory cytokines such as IL-1β.
Collapse
Affiliation(s)
- Tae-Bong Kang
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel; Department of Biotechnology, College of Biomedical and Health Science, Konkuk University, Chung-Ju, Republic of Korea
| | - Seung-Hoon Yang
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel
| | - Beata Toth
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel
| | - Andrew Kovalenko
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel
| | - David Wallach
- Department of Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel.
| |
Collapse
|
11
|
Burnstock G, Boeynaems JM. Purinergic signalling and immune cells. Purinergic Signal 2014; 10:529-64. [PMID: 25352330 PMCID: PMC4272370 DOI: 10.1007/s11302-014-9427-2] [Citation(s) in RCA: 222] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Accepted: 09/12/2013] [Indexed: 11/28/2022] Open
Abstract
This review article provides a historical perspective on the role of purinergic signalling in the regulation of various subsets of immune cells from early discoveries to current understanding. It is now recognised that adenosine 5'-triphosphate (ATP) and other nucleotides are released from cells following stress or injury. They can act on virtually all subsets of immune cells through a spectrum of P2X ligand-gated ion channels and G protein-coupled P2Y receptors. Furthermore, ATP is rapidly degraded into adenosine by ectonucleotidases such as CD39 and CD73, and adenosine exerts additional regulatory effects through its own receptors. The resulting effect ranges from stimulation to tolerance depending on the amount and time courses of nucleotides released, and the balance between ATP and adenosine. This review identifies the various receptors involved in the different subsets of immune cells and their effects on the function of these cells.
Collapse
Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK,
| | | |
Collapse
|
12
|
Pacheco PAF, Faria RX, Ferreira LGB, Paixão ICNP. Putative roles of purinergic signaling in human immunodeficiency virus-1 infection. Biol Direct 2014; 9:21. [PMID: 25351961 PMCID: PMC4218944 DOI: 10.1186/1745-6150-9-21] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 10/09/2014] [Indexed: 02/07/2023] Open
Abstract
Reviewers This article was reviewed by Neil S. Greenspan and Rachel Gerstein. Nucleotides and nucleosides act as potent extracellular messengers via the activation of the family of cell-surface receptors termed purinergic receptors. These receptors are categorized into P1 and P2 receptors (P2Rs). P2Rs are further classified into two distinct families, P2X receptors (P2XRs) and P2Y receptors (P2YRs). These receptors display broad tissue distribution throughout the body and are involved in several biological events. Immune cells express various P2Rs, and purinergic signaling mechanisms have been shown to play key roles in the regulation of many aspects of immune responses. Researchers have elucidated the involvement of these receptors in the host response to infections. The evidences indicate a dual function of these receptors, depending on the microorganism and the cellular model involved. Three recent reports have examined the relationship between the level of extracellular ATP, the mechanisms underlying purinergic receptors participating in the infection mechanism of HIV-1 in the cell. Although preliminary, these results indicate that purinergic receptors are putative pharmacological targets that should be further explored in future studies.
Collapse
Affiliation(s)
| | - Robson X Faria
- Laboratory of Cellular Communication, Oswaldo Cruz Foundation, Av, Brazil, 4365 Rio de Janeiro, Brazil.
| | | | | |
Collapse
|
13
|
Sáez PJ, Shoji KF, Aguirre A, Sáez JC. Regulation of hemichannels and gap junction channels by cytokines in antigen-presenting cells. Mediators Inflamm 2014; 2014:742734. [PMID: 25301274 PMCID: PMC4180397 DOI: 10.1155/2014/742734] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 06/19/2014] [Indexed: 12/13/2022] Open
Abstract
Autocrine and paracrine signals coordinate responses of several cell types of the immune system that provide efficient protection against different challenges. Antigen-presenting cells (APCs) coordinate activation of this system via homocellular and heterocellular interactions. Cytokines constitute chemical intercellular signals among immune cells and might promote pro- or anti-inflammatory effects. During the last two decades, two membrane pathways for intercellular communication have been demonstrated in cells of the immune system. They are called hemichannels (HCs) and gap junction channels (GJCs) and provide new insights into the mechanisms of the orchestrated response of immune cells. GJCs and HCs are permeable to ions and small molecules, including signaling molecules. The direct intercellular transfer between contacting cells can be mediated by GJCs, whereas the release to or uptake from the extracellular milieu can be mediated by HCs. GJCs and HCs can be constituted by two protein families: connexins (Cxs) or pannexins (Panxs), which are present in almost all APCs, being Cx43 and Panx1 the most ubiquitous members of each protein family. In this review, we focus on the effects of different cytokines on the intercellular communication mediated by HCs and GJCs in APCs and their impact on purinergic signaling.
Collapse
Affiliation(s)
- Pablo J. Sáez
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Alameda 340, 6513677 Santiago, Chile
| | - Kenji F. Shoji
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Alameda 340, 6513677 Santiago, Chile
| | - Adam Aguirre
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Alameda 340, 6513677 Santiago, Chile
| | - Juan C. Sáez
- Departamento de Fisiología, Pontificia Universidad Católica de Chile, Alameda 340, 6513677 Santiago, Chile
- Instituto Milenio, Centro Interdisciplinario de Neurociencias de Valparaíso, Pasaje Harrington 287, Playa Ancha, 2360103 Valparaíso, Chile
| |
Collapse
|
14
|
Jacob F, Novo CP, Bachert C, Van Crombruggen K. Purinergic signaling in inflammatory cells: P2 receptor expression, functional effects, and modulation of inflammatory responses. Purinergic Signal 2013; 9:285-306. [PMID: 23404828 PMCID: PMC3757148 DOI: 10.1007/s11302-013-9357-4] [Citation(s) in RCA: 159] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Accepted: 01/28/2013] [Indexed: 01/13/2023] Open
Abstract
Extracellular ATP and related nucleotides promote a wide range of pathophysiological responses via activation of cell surface purinergic P2 receptors. Almost every cell type expresses P2 receptors and/or exhibit regulated release of ATP. In this review, we focus on the purinergic receptor distribution in inflammatory cells and their implication in diverse immune responses by providing an overview of the current knowledge in the literature related to purinergic signaling in neutrophils, macrophages, dendritic cells, lymphocytes, eosinophils, and mast cells. The pathophysiological role of purinergic signaling in these cells include among others calcium mobilization, actin polymerization, chemotaxis, release of mediators, cell maturation, cytotoxicity, and cell death. We finally discuss the therapeutic potential of P2 receptor subtype selective drugs in inflammatory conditions.
Collapse
Affiliation(s)
- Fenila Jacob
- Upper Airways Research Laboratory, Department of Otorhinolaryngology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| | - Claudina Pérez Novo
- Upper Airways Research Laboratory, Department of Otorhinolaryngology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| | - Claus Bachert
- Upper Airways Research Laboratory, Department of Otorhinolaryngology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| | - Koen Van Crombruggen
- Upper Airways Research Laboratory, Department of Otorhinolaryngology, Ghent University Hospital, De Pintelaan 185, 9000 Ghent, Belgium
| |
Collapse
|
15
|
Waeckerle-Men Y, Mauracher A, Håkerud M, Mohanan D, Kündig TM, Høgset A, Johansen P. Photochemical targeting of antigens to the cytosol for stimulation of MHC class-I-restricted T-cell responses. Eur J Pharm Biopharm 2013; 85:34-41. [PMID: 23461859 DOI: 10.1016/j.ejpb.2013.02.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 02/01/2013] [Accepted: 02/04/2013] [Indexed: 12/18/2022]
Abstract
Tumour chemotherapy with drugs is typically associated with severe systemic and local side effects for which reason immunotherapy represents a safer alternative. However, vaccination often fails to generate the required cytotoxic CD8 T-cell responses due to insufficient access of antigens to the cytosol and the MHC class I pathway of antigen presentation. One important issue of tumour research is therefore to develop strategies that allow cytosolic targeting or endosomal escape of tumour antigens. The objective of the current study was to test whether endocytosed antigen could be delivered to MHC class I by means of photochemical internalisation (PCI). Briefly, the antigen and the photosensitiser Amphinex were loaded in vitro onto bone-marrow-derived murine dendritic cells (DCs). After light activation, which is supposed to cause disruption of OVA- and Amphinex-containing endosomes, the DCs were cultured with OVA-specific CD8 T cells or used for immunisation of mice. PCI facilitated CD8 T-cell responses as measured by IFN-γ secretion in vitro and CD8 T-cell proliferation in vivo. In conclusion, the current proof-of-concept study is the first to describe PCI-mediated immunisation and the results revealed the feasibility of this novel technology in autologous vaccination for stimulation of CD8 T-cell responses.
Collapse
|
16
|
Sakaki H, Fujiwaki T, Tsukimoto M, Kawano A, Harada H, Kojima S. P2X4 receptor regulates P2X7 receptor-dependent IL-1β and IL-18 release in mouse bone marrow-derived dendritic cells. Biochem Biophys Res Commun 2013; 432:406-11. [PMID: 23428419 DOI: 10.1016/j.bbrc.2013.01.135] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Accepted: 01/26/2013] [Indexed: 12/31/2022]
Abstract
Activation of P2X7 receptor of dendritic cells plays a significant role in inflammation through production of cytokines such as IL-1β, and recent studies have suggested structural and functional interactions of P2X7 receptor with P2X4 receptor in macrophages. However, it is unknown whether P2X4 receptor modulates P2X7 functions in dendritic cells. Here, we present evidence that expression of P2X4 receptor is required for P2X7 receptor-dependent IL-1β and IL-18 release in mouse bone marrow-derived dendritic cells (BMDCs). We confirmed expression of both P2X7 receptor and P2X4 receptor in BMDCs. Treatment of BMDCs with 3 mM ATP caused a transient, P2X4-dependent elevation, or spike, of intracellular Ca(2+) level [Ca(2+)]i, followed by the sustained P2X7-dependent increase of [Ca(2+)]i. We performed knockdown of P2X4 receptor in BMDCs by transfection with short hairpin RNA targeting this receptor. The ATP-induced initial peak of [Ca(2+)]i was decreased in P2X4-knockdown cells (P2X4-KD). Further, we found that ATP-induced IL-1β and IL-18 release from LPS-primed BMDCs was suppressed by pretreatment with P2X7 antagonist A438079 or P2X4 antagonist TNP-ATP. The P2X7-dependent IL-1β and IL-18 release was significantly lower in P2X4-KD cells. Chelation of intracellular Ca(2+) also caused suppression of ATP-induced IL-1β and IL-18 release. These results suggest that P2X4 receptor-induced Ca(2+) influx is required for effective production of IL-1β and IL-18 via activation of P2X7 receptor in BMDCs. We conclude that co-expression of P2X4 receptor with P2X7 receptor in dendritic cells leads to enhancement of inflammation through facilitation of P2X7-dependent release of pro-inflammatory cytokines.
Collapse
Affiliation(s)
- Hayato Sakaki
- Department of Radiation Biosciences, Faculty of Pharmaceutical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba, Japan
| | | | | | | | | | | |
Collapse
|
17
|
Kang TB, Yang SH, Toth B, Kovalenko A, Wallach D. Caspase-8 blocks kinase RIPK3-mediated activation of the NLRP3 inflammasome. Immunity 2012; 38:27-40. [PMID: 23260196 DOI: 10.1016/j.immuni.2012.09.015] [Citation(s) in RCA: 419] [Impact Index Per Article: 34.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2012] [Accepted: 09/20/2012] [Indexed: 11/16/2022]
Abstract
Caspase-8 deficiency in certain cells prompts chronic inflammation. One mechanism suggested to account for this inflammation is enhanced signaling for necrotic cell death, mediated by the protein kinases RIPK1 and RIPK3 that caspase-8 can cleave. We describe an activity of caspase-8 in dendritic cells that controls the initiation of inflammation in another way. Caspase-8 deficiency in these cells facilitated lipopolysaccharide-induced assembly and function of the NLRP3 inflammasome. This effect depended on the functions of RIPK1 and RIPK3, as well as of MLKL and PGAM5, two signaling proteins recently shown to contribute to RIPK3-mediated induction of necrosis. However, although enhancement of inflammasome assembly in the caspase-8-deficient cells shares proximal signaling events with the induction of necrosis, it occurred independently of cell death. These findings provide new insight into potentially pathological inflammatory processes to which RIPK1- and RIPK3-mediated signaling contributes.
Collapse
Affiliation(s)
- Tae-Bong Kang
- Department of Biological Chemistry, The Weizmann Institute of Science, 76100 Rehovot, Israel
| | | | | | | | | |
Collapse
|
18
|
Kawamura H, Kawamura T, Kanda Y, Kobayashi T, Abo T. Extracellular ATP-stimulated macrophages produce macrophage inflammatory protein-2 which is important for neutrophil migration. Immunology 2012; 136:448-58. [PMID: 22564028 DOI: 10.1111/j.1365-2567.2012.03601.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Macrophages are the major source of the chemokines macrophage inflammatory protein-2 (MIP-2) and keratinocyte-derived chemokine (KC), which play a major role in neutrophil migration to sites of inflammation. Although extracellular ATP from inflammatory tissues induces several immune responses in macrophages, it is unclear whether ATP-stimulated macrophages affect neutrophil migration. Therefore, the aim of the present study was to investigate the role of ATP-induced MIP-2 production by macrophages. When ATP was injected intraperitoneally into mice, the number of neutrophils within the peritoneal cavity markedly increased, along with the levels of MIP-2 and KC in the peritoneal lavage fluid. Consistent with this, ATP induced MIP-2 production, but not that of KC, by peritoneal exudate macrophages (PEMs) in vitro. This occurred via interactions with the P2X(7) receptor and P2Y(2) receptor. Furthermore, treatment of PEMs with ATP led to the production of reactive oxygen species. The ATP-induced MIP-2 production was inhibited by treatment with the antioxidant N-acetyl-l-cysteine. Also, MIP-2 production was inhibited by pre-incubating PEMs with inhibitors of extracellular signal-regulated kinase 1/2 or p38 mitogen-activated protein kinase. The MIP-2 neutralization reduced the increase in neutrophil numbers observed in ATP-treated mice. Taken together, these results suggest that increased production of reactive oxygen species by ATP-stimulated macrophages activates the signalling pathways that promote MIP-2 production which, in turn, induces neutrophil migration.
Collapse
Affiliation(s)
- Hiroki Kawamura
- Division of Immunology, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
| | | | | | | | | |
Collapse
|
19
|
Santos JAA, Fidalgo-Neto AA, Faria RX, Simões A, Calheiros AS, Bérenger AL, Faria-Neto HCC, Figueiredo MR, Frutuoso VSL, Alves LA. Effect of Rheedia longifolia leaf extract and fractions on the P2X₇ receptor in vitro: novel antagonists? J Med Food 2011; 14:920-9. [PMID: 21554119 DOI: 10.1089/jmf.2010.0184] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Recently, the P2X(7) receptor has been reported to be associated with chronic inflammatory and neuropathic pain. Because Rheedia longifolia extract has analgesic and anti-inflammatory activity, we evaluated the in vitro inhibitory potential of methanol extract and fractions from its leaves on the P2X(7) purinergic receptor. The activity of P2X(7) was studied with a dye uptake assay and with the whole-cell patch clamp technique in mouse peritoneal macrophages treated with methanol extract of R. longifolia leaves and fractions. The dye uptake was evaluated by flow cytometry and fluorescence microscopy. The R. longifolia extract and some fractions showed an inhibitory effect on the P2X(7) purinergic receptor in a dose-dependent manner. The ethyl acetate fraction exhibited the most potent inhibitory effects. The methanol extract and the butanol fraction showed the same inhibitory effects, despite their lower potency compared with the other fractions. The R. longifolia extract and some of its fractions may be anti-inflammatory because of their inhibitory effect on the P2X(7) receptor. Further investigation is needed to determine the pattern of inhibition and selectivity. Chromatographic analysis indicated the presence of bisflavonoids in the methanol extract fractions. A member of this chemical family is the most probable active compound responsible for the P2X(7) inhibitory effects present in the R. Longifolia extract and fractions.
Collapse
Affiliation(s)
- José A A Santos
- Laboratory Evaluation and Promotion of Environmental Health, Oswaldo Cruz Institute (FIOCRUZ), Rio de Janeiro, Brazil
| | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Tran JNSN, Pupovac A, Taylor RM, Wiley JS, Byrne SN, Sluyter R. Murine epidermal Langerhans cells and keratinocytes express functional P2X7 receptors. Exp Dermatol 2011; 19:e151-7. [PMID: 20113349 DOI: 10.1111/j.1600-0625.2009.01029.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Extracellular ATP via the activation of purinergic P2 receptors has an emerging role in cutaneous biology; however, the distribution of these receptors in mouse skin is poorly defined. This study investigated whether murine epidermal cell subpopulations express functional purinergic P2X(7) receptors. P2X(7) expression was examined by immunoblotting and immunofluorescence staining of epidermal cells from C57Bl/6 mice. P2X(7) function was evaluated by nucleotide-induced ethidium(+) uptake measurements in epidermal cells from C57Bl/6 mice, and from P2X(7) deficient mice and wild-type littermate controls. P2X(7) was detected in whole epidermal cell preparations, and specifically on Langerhans cells (LCs) and keratinocytes (KCs). ATP induced ethidium(+) uptake into LCs and KCs, with EC(50) values of 503 and 482 microm, respectively. BzATP, and to a lesser extent ATPgammaS and ADP, also induced ethidium(+) uptake; while UTP, alphabeta-meth-ATP and NAD were ineffective. ATP-induced ethidium(+) uptake was impaired by Na(+) and Mg(2+), and the P2X(7) antagonist, A-438079 and was absent in LCs and KCs from P2X(7) deficient mice. These results demonstrate that murine LCs and KCs express functional P2X(7), and support a role for this receptor in cutaneous biology.
Collapse
Affiliation(s)
- Jimmy N S N Tran
- Department of Medicine, Nepean Clinical School, University of Sydney, Penrith, NSW, Australia
| | | | | | | | | | | |
Collapse
|
21
|
Preservation of differentiation and clonogenic potential of human hematopoietic stem and progenitor cells during lyophilization and ambient storage. PLoS One 2010; 5. [PMID: 20824143 PMCID: PMC2931707 DOI: 10.1371/journal.pone.0012518] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2010] [Accepted: 07/20/2010] [Indexed: 01/19/2023] Open
Abstract
Progenitor cell therapies show great promise, but their potential for clinical applications requires improved storage and transportation. Desiccated cells stored at ambient temperature would provide economic and practical advantages over approaches employing cell freezing and subzero temperature storage. The objectives of this study were to assess a method for loading the stabilizing sugar, trehalose, into hematopoietic stem and progenitor cells (HPC) and to evaluate the effects of subsequent freeze-drying and storage at ambient temperature on differentiation and clonogenic potential. HPC were isolated from human umbilical cord blood and loaded with trehalose using an endogenous cell surface receptor, termed P2Z. Solution containing trehalose-loaded HPC was placed into vials, which were transferred to a tray freeze-dryer and removed during each step of the freeze-drying process to assess differentiation and clonogenic potential. Control groups for these experiments were freshly isolated HPC. Control cells formed 1450+/-230 CFU-GM, 430+/-140 BFU-E, and 50+/-40 CFU-GEMM per 50 microL. Compared to the values for the control cells, there was no statistical difference observed for cells removed at the end of the freezing step or at the end of primary drying. There was a gradual decrease in the number of CFU-GM and BFU-E for cells removed at different temperatures during secondary drying; however, there were no significant differences in the number of CFU-GEMM. To determine storage stability of lyophilized HPC, cells were stored for 4 weeks at 25 degrees C in the dark. Cells reconstituted immediately after lyophilization produced 580+/-90 CFU-GM ( approximately 40%, relative to unprocessed controls p<0.0001), 170+/-70 BFU-E (approximately 40%, p<0.0001), and 41+/-22 CFU-GEMM (approximately 82%, p = 0.4171), and cells reconstituted after 28 days at room temperature produced 513+/-170 CFU-GM (approximately 35%, relative to unprocessed controls, p<0.0001), 112+/-68 BFU-E (approximately 26%, p<0.0001), and 36+/-17 CFU-GEMM ( approximately 82%, p = 0.2164) These studies are the first to document high level retention of CFU-GEMM following lyophilization and storage for 4 weeks at 25 degrees C. This type of flexible storage stability would potentially permit the ability to ship and store HPC without the need for refrigeration.
Collapse
|
22
|
Faria RX, Cascabulho CM, Reis RAM, Alves LA. Large-conductance channel formation mediated by P2X7 receptor activation is regulated through distinct intracellular signaling pathways in peritoneal macrophages and 2BH4 cells. Naunyn Schmiedebergs Arch Pharmacol 2010; 382:73-87. [PMID: 20508916 DOI: 10.1007/s00210-010-0523-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2010] [Accepted: 05/05/2010] [Indexed: 10/19/2022]
Abstract
The P2X(7) receptor (P2X7R) is a ligand-gated ATP receptor that acts as a low- and large-conductance channel (pore) and is known to be coupled to several downstream effectors. Recently, we demonstrated that the formation of a large-conductance channel associated with the P2X(7) receptor is induced by increasing the intracellular Ca(2+) concentration (Faria et al., Am J Physiol Cell Physiol 297:C28-C42, 2005). Here, we investigated the intracellular signaling pathways associated with P2X(7) large-conductance channel formation using the patch clamp technique in conjunction with fluorescent imaging and flow cytometry assays in 2BH4 cells and peritoneal macrophages. Different antagonists were applied to investigate the following pathways: Ca(2+)-calmodulin, phospholipase A, phospholipase D, phospholipase C, protein kinase C (PKC), mitogen-activated protein kinase (MAPK), MAPK/extracellular signal-regulated kinase, phosphoinositide 3-kinase (PI3K), and cytoskeletal proteins. Macroscopic ionic currents induced by 1 mM ATP were reduced by 85% in the presence of PKC antagonists. The addition of antagonists for MAPK, PI3K, and the cytoskeleton (actin, intermediary filament, and microtubule) blocked 92%, 83%, and 95% of the ionic currents induced by 1 mM ATP, respectively. Our results show that PKC, MAPK, PI3K, and cytoskeletal components are involved in P2X(7) receptor large-channel formation in 2BH4 cells and peritoneal macrophages.
Collapse
Affiliation(s)
- R X Faria
- Laboratory of Cellular Communication, Department of Immunology, Oswaldo Cruz Institute, FIOCRUZ (Oswaldo Cruz Foundation), Av. Brazil, 4365, Manguinhos, Rio de Janeiro 21045-900, Brazil.
| | | | | | | |
Collapse
|
23
|
Liu L, Zou J, Liu X, Jiang LH, Li J. Inhibition of ATP-induced macrophage death by emodin via antagonizing P2X7 receptor. Eur J Pharmacol 2010; 640:15-9. [PMID: 20452342 DOI: 10.1016/j.ejphar.2010.04.036] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2009] [Revised: 03/19/2010] [Accepted: 04/23/2010] [Indexed: 12/21/2022]
Abstract
Emodin (1,3,8-trihydroxy-6-methylanthraquinone), an anthraquinone derivative from Rheum officinale Baill, exhibits anti-inflammatory and immunosuppressive activities, however, the underlying mechanisms are not fully understood. This study examined the effects of emodin on ATP-evoked responses in rat peritoneal macrophages and in human embryonic kidney 293 cells (HEK293) heterologously expressing the cloned rat P2X7 receptor. Emodin reduced macrophage death induced by millimolar ATP in a concentration-dependent manner with the half of maximal inhibition values (IC50) of 0.2 microM. It also strongly inhibited ATP-induced dye uptake or pore formation, a hallmark property associated with P2X7 receptor activation, and 2',3'-O-(benzoyl-4-benzoyl)-ATP (BzATP) induced increases in intracellular Ca2+ concentrations in macrophages with an IC50 of 0.5 microM. Furthermore, emodin significantly suppressed BzATP-evoked currents in P2X7 receptor expressing HEK293 cells with an IC50 of 3.4 microM. Taken together, these results provide compelling evidence for a novel action of emodin as a P2X7 receptor antagonist, which may underlie its anti-inflammatory and immunosuppressive activities.
Collapse
Affiliation(s)
- Lijun Liu
- Department of Biophysics, School of Physics and Key Laboratory of Bioactive Materials of Education Ministry, Nankai University, Tianjin, 300071, PR China
| | | | | | | | | |
Collapse
|
24
|
P2 receptor-mediated signaling in mast cell biology. Purinergic Signal 2009; 6:3-17. [PMID: 19921464 DOI: 10.1007/s11302-009-9173-z] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2009] [Accepted: 10/23/2009] [Indexed: 12/22/2022] Open
Abstract
Mast cells are widely recognized as effector cells of allergic inflammatory reactions. They contribute to the pathogenesis of different chronic inflammatory diseases, wound healing, fibrosis, thrombosis/fibrinolysis, and anti-tumor immune responses. In this paper, we summarized the role of P2X and P2Y receptors in mast cell activation and effector functions. Mast cells are an abundant source of ATP which is stored in their granules and secreted upon activation. We discuss the contribution of mast cells to the extracellular ATP release and to the maintenance of extracellular nucleotides pool. Recent publications highlight the importance of purinergic signaling for the pathogenesis of chronic airway inflammation. Therefore, the role of ATP and P2 receptors in allergic inflammation with focus on mast cells was analyzed. Finally, ATP functions as mast cell autocrine/paracrine factor and as messenger in intercellular communication between mast cells, nerves, and glia in the central nervous system.
Collapse
|
25
|
Varma R, Chai Y, Troncoso J, Gu J, Xing H, Stojilkovic SS, Mattson MP, Haughey NJ. Amyloid-beta induces a caspase-mediated cleavage of P2X4 to promote purinotoxicity. Neuromolecular Med 2009; 11:63-75. [PMID: 19562525 DOI: 10.1007/s12017-009-8073-2] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Accepted: 06/16/2009] [Indexed: 11/25/2022]
Abstract
Overproduction of the beta-amyloid fragment 1-42 (A beta(1-42)) is thought to contribute to synaptic dysfunction and neuronal death in Alzheimer's disease. Mounting evidence suggests that purinergic receptors play critical roles in synaptic plasticity and neuronal survival, but the potential involvement of these receptors in A beta(1-42)-induced synaptic dysfunction and neuronal death has not been addressed. Here we report that A beta(1-42) promoted accumulation of the calcium-permeable purinergic receptor P2X4 in neurons. We also report evidence that A beta(1-42) induced a caspase-3-mediated cleavage of the receptor that slowed channel closure times and prevented agonist-induced internalization of the receptor. Molecular interference to reduce the expression of P2X4 in primary rodent neurons attenuated A beta(1-42)-induced neuronal death while induced expression of P2X4 in a neuronal cell line that does not normally express P2-receptors enhanced the toxic effect of A beta(1-42). Together these findings suggest that A beta(1-42)-induced synaptic dysfunction and neuronal death may involve perturbations in P2X4 purinergic receptors.
Collapse
Affiliation(s)
- R Varma
- Department of Neurology, Johns Hopkins, University School of Medicine, Meyer 6-109, 600 N. Wolfe St., Baltimore, MD 21287, USA
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Ohtani T, Mizuashi M, Nakagawa S, Sasaki Y, Fujimura T, Okuyama R, Aiba S. TGF-beta1 dampens the susceptibility of dendritic cells to environmental stimulation, leading to the requirement for danger signals for activation. Immunology 2009; 126:485-99. [PMID: 19278421 DOI: 10.1111/j.1365-2567.2008.02919.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
In contrast to its favourable effects on Langerhans cell (LC) differentiation, transforming growth factor (TGF)-beta1 has been reported to prevent dendritic cells from maturing in response to tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta, or lipopolysaccharide (LPS). We first characterized the effects of TGF-beta1 on dendritic cell function by testing the response of TGF-beta1-treated monocyte-derived dendritic cells (MoDCs) to maturation stimuli that LCs receive in the epidermis, namely, haptens, ATP and ultraviolet (UV). TGF-beta1 treatment, which augmented E-cadherin and down-regulated dendritic cell-specific ICAM3-grabbing non-integrin on MoDCs, significantly suppressed their CD86 expression and hapten-induced expression of IL-1beta and TNF-alpha mRNA and protein. As TGF-beta1-treated MoDCs lacked Langerin expression, we demonstrated the suppressive effects of TGF-beta1 on haematopoietic progenitor cell-derived dendritic cells expressing both CD1a and Langerin. These suppressive effects of TGF-beta1 increased with the duration of treatment. Furthermore, TGF-beta1-treated MoDCs became resistant to apoptosis/necrosis induced by high hapten, ATP or UV doses. This was mainly attributable to dampened activation of p38 mitogen-activated protein kinase (MAPK) in TGF-beta1-treated MoDCs. Notably, although ATP or hapten alone could only induce CD86 expression weakly and could not augment the allogeneic T-cell stimulatory function of TGF-beta1-treated MoDCs, ATP and hapten synergized to stimulate these phenotypic and functional changes. Similarly, 2,4-dinitro, 1-chlorobenzene (DNCB) augmented the maturation of TGF-beta1-treated MoDCs upon co-culture with a keratinocyte cell line, in which ATP released by the hapten-stimulated keratinocytes synergized with the hapten to induce their maturation. These data may suggest that TGF-beta1 protects LCs from being overactivated by harmless environmental stimulation, while maintaining their ability to become activated in response to danger signals released by keratinocytes.
Collapse
Affiliation(s)
- Tomoyuki Ohtani
- Department of Dermatology, Tohoku University Graduate School of Medicine, Seiryo-machi, Aobaku, Sendai, Japan
| | | | | | | | | | | | | |
Collapse
|
27
|
Ben Addi A, Lefort A, Hua X, Libert F, Communi D, Ledent C, Macours P, Tilley SL, Boeynaems JM, Robaye B. Modulation of murine dendritic cell function by adenine nucleotides and adenosine: involvement of the A(2B) receptor. Eur J Immunol 2008; 38:1610-20. [PMID: 18465770 DOI: 10.1002/eji.200737781] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Adenosine triphosphate has previously been shown to induce semi-mature human monocyte-derived dendritic cells (DC). These are characterized by the up-regulation of co-stimulatory molecules, the inhibition of IL-12 and the up-regulation of some genes involved in immune tolerance, such as thrombospondin-1 and indoleamine 2,3-dioxygenase. The actions of adenosine triphosphate are mediated by the P2Y(11) receptor; since there is no functional P2Y(11) gene in the murine genome, we investigated the action of adenine nucleotides on murine DC. Adenosine 5'-(3-thiotriphosphate) and adenosine inhibited the production of IL-12p70 by bone marrow-derived DC (BMDC). These inhibitions were relieved by 8-p-sulfophenyltheophylline, an adenosine receptor antagonist. The use of selective ligands and A(2B) (-/-) BMDC indicated the involvement of the A(2B) receptor. A microarray experiment, confirmed by quantitative PCR, showed that, in presence of LPS, 5'-(N-ethylcarboxamido) adenosine (NECA, the most potent A(2B) receptor agonist) regulated the expression of several genes: arginase I and II, thrombospondin-1 and vascular endothelial growth factor were up-regulated whereas CCL2 and CCL12 were down-regulated. We further showed that NECA, in combination with LPS, increased the arginase I enzymatic activity. In conclusion, the described actions of adenine nucleotides on BMDC are mediated by their degradation product, adenosine, acting on the A(2B) receptor, and will possibly lead to an impairment of Th1 response or tolerance.
Collapse
Affiliation(s)
- Abduelhakem Ben Addi
- Institute of Interdisciplinary Research, IRIBHM, Université Libre de Bruxelles, Gosselies, Belgium
| | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Devogelaere B, Sammels E, De Smedt H. The IRBIT domain adds new functions to the AHCY family. Bioessays 2008; 30:642-52. [PMID: 18536033 DOI: 10.1002/bies.20772] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
During the past few years, the IRBIT domain has emerged as an important add-on of S-adenosyl-L-homocystein hydrolase (AHCY), thereby creating the new family of AHCY-like proteins. In this review, we discuss the currently available data on this new family of proteins. We describe the IRBIT domain as a unique part of these proteins and give an overview of its regulation via (de)phosphorylation and proteolysis. The second part of this review is focused on the potential functions of the AHCY-like proteins. We propose that the IRBIT domain serves as an anchor for targeting AHCY-like proteins towards cytoplasmic targets. This leads to regulation of (i) intracellular Ca2+ via the inositol 1,4,5-trisphosphate receptor (IP3R), (ii) intracellular pH via the Na+/HCO3 - cotransporters (NBCs); whereas inactivation of the IRBIT domain induces (iii) nuclear translocation and regulation of AHCY activity. Dysfunction of AHCY-like proteins will disturb these three important functions, with various biological implications.
Collapse
Affiliation(s)
- Benoit Devogelaere
- Laboratory of Molecular and Cellular Signalling, Department of Molecular Cell Biology, Katholieke Universiteit Leuven, Belgium
| | | | | |
Collapse
|
29
|
Noguchi T, Ishii K, Fukutomi H, Naguro I, Matsuzawa A, Takeda K, Ichijo H. Requirement of reactive oxygen species-dependent activation of ASK1-p38 MAPK pathway for extracellular ATP-induced apoptosis in macrophage. J Biol Chem 2008; 283:7657-65. [PMID: 18211888 DOI: 10.1074/jbc.m708402200] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Extracellular ATP, an autocrine or paracrine intercellular transmitter, is known to induce apoptosis in macrophages. However, the precise signaling mechanisms of ATP-induced apoptosis remain to be elucidated. Here we showed that activation of p38 mitogen-activated protein kinase (MAPK) plays a critical role in ATP-induced apoptosis. p38 activation and apoptosis in macrophages were induced by ATP. ATP-induced apoptosis was mediated in part by production of reactive oxygen species (ROS) derived from NOX2/gp91(phox), a component of the NADPH oxidase complex expressed in macrophages and neutrophils. Furthermore, ATP-induced ROS generation, p38 activation, and apoptosis were almost completely inhibited by selective P2X(7) receptor antagonists. We also found that ATP-induced apoptosis were diminished in ASK1-deficient macrophages accompanied by the lack of p38 activation. These results demonstrate that ROS-mediated activation of the ASK1-p38 MAPK pathway downstream of P2X(7) receptor is required for ATP-induced apoptosis in macrophages.
Collapse
Affiliation(s)
- Takuya Noguchi
- Laboratory of Cell Signaling, Graduate School of Pharmaceutical Sciences, Center of Excellence Program, Japan Science and Technology Corporation, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | | | | | | | | | | | | |
Collapse
|
30
|
Coutinho-Silva R, Robson T, Beales PE, Burnstock G. Changes in expression of P2X7 receptors in NOD mouse pancreas during the development of diabetes. Autoimmunity 2007; 40:108-16. [PMID: 17364502 DOI: 10.1080/08916930601118841] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
This study examined the expression of P2X7 receptors in pancreatic islets of the non-obese diabetic (NOD) mouse model of human autoimmune insulin-dependent diabetes mellitus, to determine whether they are involved in islet cell destruction during early- and late-developing diabetes. Pancreatic cells containing glucagon (alpha-cells), insulin (beta-cells) and somatostatin (delta-cells) were co-localized with P2X7 receptors. We examined P2X7 receptor expression in normal and diabetic spleens using flow cytometry. In non-diabetic NOD controls, P2X7 receptors were expressed in glucagon-containing cells at the periphery of islets, being consistent with previous studies. In early NOD diabetes (12 weeks), there was migration of peripheral P2X7 receptor positive, glucagon-containing cells into the center of islets. In late NOD diabetes (34 weeks), P2X7 receptor- and glucagon-stained alpha-cells were gone from islets. Migration of macrophages and dendritic cells into islets took place, but they lacked P2X7 immunoreactivity. There was no significant difference in the percentage of splenic macrophages stained for P2X7 receptors from control and diabetic spleens. In conclusion, in the development of early to late diabetes, there is a down-regulation of P2X7 receptors on islet cells and a loss of alpha- and beta-cell populations. P2X7 receptor signalling might be involved in alpha-cell clearance from late diabetic islets.
Collapse
Affiliation(s)
- Robson Coutinho-Silva
- Autonomic Neuroscience Centre, Royal Free and University College Medical School, Rowland Hill Street, London, UK
| | | | | | | |
Collapse
|
31
|
Ferrari D, Gorini S, Callegari G, la Sala A. Shaping immune responses through the activation of dendritic cells' P2 receptors. Purinergic Signal 2006; 3:99-107. [PMID: 18404423 PMCID: PMC2096769 DOI: 10.1007/s11302-006-9024-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2006] [Revised: 05/30/2006] [Accepted: 06/19/2006] [Indexed: 12/22/2022] Open
Abstract
Dendritic cells (DCs) activate and shape the adaptive immune response by capturing antigens, migrating to peripheral lymphoid organs where naïve T cells reside, expressing high levels of MHC and costimulatory molecules and secreting cytokines and chemokines. DCs are endowed with a high degree of functional plasticity and their functions are tightly regulated. Besides initiating adaptive immune responses, DCs play a key role in maintaining peripheral tolerance toward self-antigens. On the basis of the information gathered from the tissue where they reside, DCs adjust their functional activity to ensure that protective immunity is favoured while unwanted or exaggerated immune responses are prevented. A wide variety of signals from neighbouring cells affecting DC functional activity have been described. Here we will discuss the complex role of extracellular nucleotides in the regulation of DC function and the role of P2 receptors as possible tools to manipulate immune responses.
Collapse
Affiliation(s)
- Davide Ferrari
- Department of Experimental and Diagnostic Medicine, Section of General Pathology, Interdisciplinary Center for the Study of Inflammation (ICSI), University of Ferrara, Ferrara, Italy
| | | | | | | |
Collapse
|
32
|
Wang MX, Ren LM. Growth inhibitory effect and apoptosis induced by extracellular ATP and adenosine on human gastric carcinoma cells: involvement of intracellular uptake of adenosine. Acta Pharmacol Sin 2006; 27:1085-92. [PMID: 16867263 DOI: 10.1111/j.1745-7254.2006.00342.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
AIM To study the growth inhibitory and apoptotic effects of adenosine triphosphate (ATP) and adenosine (ADO) on human gastric carcinoma (HGC)-27 cells in vitro and the mechanisms related to the actions of ATP and ADO. METHODS MTT assay was used to determine the reduction of cell viability. The morphological changes of HGC-27 cells induced by ATP or ADO were observed under fluorescence light microscope by acridine orange/ethidium bromide double-stained cells. The internucleosomal fragmentation of genomic DNA was detected by agarose gel electrophoresis. The apoptotic rate and cell-cycle analysis after treatment with ATP or ADO was determined by flow cytometry. RESULTS ATP, ADO and the intermediate metabolites, ADP and AMP, and the agonist of purinergic receptors, reduced cell viability of HGC-27 cells at doses of 0.3 and 1.0 mmol/L. The distribution of cell cycle phase and proliferation index (PI) value of HGC-27 cells changed when exposed to ATP or ADO at the concentrations of 0.1, 0.3 and 1 mmol/L for 48 h. ATP and ADO both altered the distribution of cell cycle phase via G0/G1- phase arrest and significantly decreased PI value. Under light microscope, the tumor cells exposed to 0.3 mmol/L ATP or ADO displayed morphological changes of apoptosis; a ladder-like pattern of DNA fragmentation obtained from HGC-27 cells treated with 0.1-1 mmol/L ATP or ADO appeared in agarose gel electrophoresis; ATP and ADO induced the apoptosis of HGC-27 cells in a dose-dependent manner at concentrations between 0.03-1 mmol/L. The maximum apoptotic rate of HGC-27 cells exposed to ATP or ADO for 48 h was 13.53% or 15.9%, respectively. HGC-27 cell death induced by ATP or ADO was significantly inhibited by dipyridamole (10 mmol/L), an inhibitor of adenosine transporter, but was not affected by aminophylline, a broad inhibitor of P1 receptors and pyridoxal-phosphate-6-azophenyl-2, 4-disulphonic acid tetrasodium salt (30 micromol/L), a non-selective antagonist of P2 receptors. CONCLUSION Extracellular ATP and ADO reduced the cell viability, arrested cell cycle and induced apoptosis in HGC-27 cell line by intracellular uptake of ADO. One of the main routes of ATP-induced apoptosis in HGC-27 cells is through the breakdown to adenosine.
Collapse
Affiliation(s)
- Ming-Xia Wang
- The Fourth Affiliated Hospital, Hebei Medical University, Shijiazhuang 050011, China
| | | |
Collapse
|
33
|
Bours MJL, Swennen ELR, Di Virgilio F, Cronstein BN, Dagnelie PC. Adenosine 5'-triphosphate and adenosine as endogenous signaling molecules in immunity and inflammation. Pharmacol Ther 2006; 112:358-404. [PMID: 16784779 DOI: 10.1016/j.pharmthera.2005.04.013] [Citation(s) in RCA: 766] [Impact Index Per Article: 42.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2005] [Accepted: 04/20/2005] [Indexed: 02/07/2023]
Abstract
Human health is under constant threat of a wide variety of dangers, both self and nonself. The immune system is occupied with protecting the host against such dangers in order to preserve human health. For that purpose, the immune system is equipped with a diverse array of both cellular and non-cellular effectors that are in continuous communication with each other. The naturally occurring nucleotide adenosine 5'-triphosphate (ATP) and its metabolite adenosine (Ado) probably constitute an intrinsic part of this extensive immunological network through purinergic signaling by their cognate receptors, which are widely expressed throughout the body. This review provides a thorough overview of the effects of ATP and Ado on major immune cell types. The overwhelming evidence indicates that ATP and Ado are important endogenous signaling molecules in immunity and inflammation. Although the role of ATP and Ado during the course of inflammatory and immune responses in vivo appears to be extremely complex, we propose that their immunological role is both interdependent and multifaceted, meaning that the nature of their effects may shift from immunostimulatory to immunoregulatory or vice versa depending on extracellular concentrations as well as on expression patterns of purinergic receptors and ecto-enzymes. Purinergic signaling thus contributes to the fine-tuning of inflammatory and immune responses in such a way that the danger to the host is eliminated efficiently with minimal damage to healthy tissues.
Collapse
Affiliation(s)
- M J L Bours
- Maastricht University, Department of Epidemiology, Nutrition and Toxicology Research Institute Maastricht, P.O. Box 616, 6200 MD Maastricht, The Netherlands.
| | | | | | | | | |
Collapse
|
34
|
Xiang Z, Lv J, Jiang P, Chen C, Jiang B, Burnstock G. Expression of P2X receptors on immune cells in the rat liver during postnatal development. Histochem Cell Biol 2006; 126:453-63. [PMID: 16612582 DOI: 10.1007/s00418-006-0180-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2006] [Indexed: 11/26/2022]
Abstract
Single and double-labeling immunofluorescence and RT-PCR expression of P2X receptor proteins and mRNAs were used in a study of the liver of postnatal rats. OX62 and ED1 were used as markers for dendritic and macrophage (Kupffer) cells respectively. The results showed that the P2X6 receptor subunit was up-regulated by 15-fold on hepatic sinusoid cells during postnatal days P1 to P60. Subpopulations of Kupffer cells co-expressed P2X4 and P2X6 receptor subunits and dendritic cells co-expressed P2X4 and P2X7 receptor subunits. Lipopolysaccharide (endotoxin) injected into the peritoneal cavity led to increased expression of the P2X6 receptor on Kupffer cells, suggesting that the P2X6 receptor subunit may be up-regulated by endotoxin. This study presents the first evidence that P2X receptors are widely distributed in the rat liver immune system and that activation of Kupffer and dendritic cells in the rat liver might be regulated by extracellular ATP.
Collapse
Affiliation(s)
- Zhenghua Xiang
- Department of Biochemistry and Molecular Biology, Second Military Medical University, 200433, Shanghai, People's Republic of China
| | | | | | | | | | | |
Collapse
|
35
|
Georgiou JG, Skarratt KK, Fuller SJ, Martin CJ, Christopherson RI, Wiley JS, Sluyter R. Human epidermal and monocyte-derived langerhans cells express functional P2X receptors. J Invest Dermatol 2005; 125:482-90. [PMID: 16117789 DOI: 10.1111/j.0022-202x.2005.23835.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Monocyte-derived dendritic cells (Mo-DC) express functional P2X7 receptors; however, the expression of these receptors on tissue-derived dendritic cells including epidermal Langerhans cells (LC) is unknown. Using immunolabeling and flow cytometry, we demonstrated that P2X7 was present on both human epidermal LC and monocyte-derived LC (Mo-LC), as well as on human keratinocytes. The ecto-ATPDase (CD39) was also present on LC, but not keratinocytes. The P2X7 agonists, 2'- and 3'-0(4-benzoylbenzoyl) adenosine 5'-triphosphate (BzATP) or ATP, but neither adenosine 5'-diphosphate (ADP) nor uridine 5'-triphosphate (UTP), induced ethidium+ uptake into these cells. Furthermore, ATP-induced ethidium+ uptake into epidermal LC, Mo-LC and keratinocytes was inhibited by the specific P2X7 antagonist, KN-62 (1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl-L-tyrosyl]-4-phenylpiperazine). ATP-induced ethidium+ uptake into Mo-LC and Mo-DC was 2- and 3-fold greater, respectively, than that for fresh monocytes. P2X7 activation on LC induced downstream signaling events, as BzATP or ATP, but neither ADP nor UTP, induced shedding of the low-affinity receptor for IgE (CD23) from Mo-LC. This process was inhibited by KN-62. Finally, ATP-induced ethidium+ uptake and CD23 shedding were impaired in Mo-LC obtained from subjects homozygous for the loss-of-function Glu-496 to Ala polymorphism in the P2X7 receptor. These results demonstrate that human LC express functional P2X7 receptors, and suggest a role for this receptor in the skin immune system.
Collapse
Affiliation(s)
- Jennifer G Georgiou
- Department of Medicine, University of Sydney at Nepean Hospital, Penrith, NSW, Australia
| | | | | | | | | | | | | |
Collapse
|
36
|
Wang MX, Ren LM, Shan BE. Inhibitory effects of extracellular adenosine triphosphate on growth of esophageal carcinoma cells. World J Gastroenterol 2005; 11:5915-9. [PMID: 16273599 PMCID: PMC4436710 DOI: 10.3748/wjg.v11.i38.5915] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To study the growth inhibitory effects of ATP on TE-13 human squamous esophageal carcinoma cells in vitro.
METHODS: MTT assay was used to determine the inhibition of proliferation of ATP or adenosine (ADO) on TE-13 cell line. The morphological changes of TE-13 cells induced by ATP or ADO were observed under fluorescence light microscope by acridine orange (AO)/ethidium bromide (EB) double stained cells. The internucleosomal fragmentation of genomic DNA was detected by agarose gel electrophoresis. The apoptotic rate and cell cycle after treatment with ATP or ADO were determined by flow cytometry.
RESULTS: ATP and ADO produced inhibitory effects on TE-13 cells at the concentration between 0.01 and 1.0 mmol/L. The IC50 of TE-13 cells exposed to ATP or ADO for 48 and 72 h was 0.71 or 1.05, and 0.21 or 0.19 mmol/L, respectively. The distribution of cell cycle phase and proliferation index (PI) value of TE-13 cells changed, when being exposed to ATP or ADO at the concentrations of 0.01, 0.1, and 1 mmol/L for 48 h. ATP and ADO inhibited the cell proliferation by changing the distribution of cell cycle phase via either G0/G1 phase (ATP or ADO, 1 mmol/L) or S phase (ATP, 0.1 mmol/L) arrest. Under light microscope, the tumor cells exposed to 0.3 mmol/L ATP or ADO displayed morphological changes of apoptosis. A ladder-like pattern of DNA fragmentation was obtained from TE-13 cells treated with 0.1-1 mmol/L ATP or ADO in agarose gel electrophoresis. ATP and ADO induced apoptosis of TE-13 cells in a dose-dependent manner at the concentration between 0.03 and 1 mmol/L. The maximum apoptotic rate of TE-13 cells exposed to ATP or ADO for 48 h was 16.63% or 16.9%, respectively.
CONCLUSION: ATP and ADO inhibit cell proliferation, arrest cell cycle, and induce apoptosis of TE-13 cell line.
Collapse
Affiliation(s)
- Ming-Xia Wang
- School of Pharmacy, Hebei Medical University, Shijiazhuang 050017, Hebei Province, China
| | | | | |
Collapse
|
37
|
Kobayashi N, DeLano FA, Schmid-Schönbein GW. Oxidative Stress Promotes Endothelial Cell Apoptosis and Loss of Microvessels in the Spontaneously Hypertensive Rats. Arterioscler Thromb Vasc Biol 2005; 25:2114-21. [PMID: 16037565 DOI: 10.1161/01.atv.0000178993.13222.f2] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Endothelial cell apoptosis caused by oxidative stress may lead to the loss of microvessels (rarefaction) in hypertension. We examine here the effects of antioxidants on cell apoptosis and rarefaction. METHODS AND RESULTS The juvenile spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto (WKY) rats were treated with superoxide scavengers, Tempol or Tiron, during growth. After the treatment, oxidative stress status, endothelial cell apoptosis rate, and microvessel length density in skeletal muscle and mesentery were evaluated in comparison with age-matched controls. Untreated 16-week-old SHR had higher oxidative stress (P<0.01) and cell apoptosis rate (P<0.05) and lower microvessel length density (371+/-17 mm/mm3 [P<0.01]) compared with age-matched WKY rats (435+/-15 mm/mm3). In the SHR, but not in WKY rats, systemically applied antioxidants attenuated oxidative stress and cell apoptosis rate (P<0.05 versus untreated controls) and prevented the loss of microvessels (411+/-15 mm/mm3 for Tempol [P<0.01 versus untreated control] and 399+/-17 mm/mm3 for Tiron [P<0.05]). CONCLUSIONS Antioxidant treatment with cell-permeable superoxide scavengers inhibits endothelial cell apoptosis and prevents microvessel rarefaction in the SHR during growth.
Collapse
Affiliation(s)
- Nobuhiko Kobayashi
- Department of Bioengineering, Whitaker Institute of Biomedical Engineering, University of California, San Diego, La Jolla, CA 92093-0412, USA
| | | | | |
Collapse
|
38
|
Tapia-Vieyra JV, Arellano RO, Mas-Oliva J. ARP2 a novel protein involved in apoptosis of LNCaP cells shares a high degree homology with splicing factor Prp8. Mol Cell Biochem 2005; 269:189-201. [PMID: 15786732 DOI: 10.1007/s11010-005-3084-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The mechanism of apoptosis has been recognized as an important event in processes such as cellular development and homeostasis, as well as degenerative conditions like cancer. Prostate cancer during its advanced stages develops androgen independent cells that ultimately overgrow and promote metastatic events. Our group employing androgen independent LNCaP cells have previously proposed, based on electrophysiological findings, that apoptosis induced cells overexpress a cell death calcium channel-like molecule. Here we report the cloning and expression in Xenopus laevis oocytes of apoptosis regulated protein 2 (ARP2), a protein overexpressed in apoptosis induced LNCaP cells capable to induce calcium inward currents and apoptosis typical morphology changes in oocytes injected with arp2 mRNA. Our results also indicate that clone arp2 cDNA (1.3Kb) shares a 99% homology with a small fragment that corresponds to 18% of the complete sequence of Prp8 cDNA (7.0 Kb), a molecule that codifies for an important protein in the assembly of the spliceosome. We propose that protein ARP2 as a fragment of protein Prp8, corresponds to a molecule with a new function in apoptosis related phenomena.
Collapse
Affiliation(s)
- J V Tapia-Vieyra
- Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México, DF, México
| | | | | |
Collapse
|
39
|
Extracellular ATP induces cytokine expression and apoptosis through P2X7 receptor in murine mast cells. THE JOURNAL OF IMMUNOLOGY 2005; 174:3880-90. [PMID: 15778342 DOI: 10.4049/jimmunol.174.7.3880] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Extracellular ATP and other nucleotides act through specific cell surface receptors and regulate a wide variety of cellular responses in many cell types and tissues. In this study, we demonstrate that murine mast cells express several P2Y and P2X receptor subtypes including P2X(7), and describe functional responses of these cells to extracellular ATP. Stimulation of bone marrow-derived mast cells (BMMC), as well as MC/9 and P815 mast cell lines with millimolar concentrations of ATP, resulted in Ca(2+) influx across the cellular membrane and cell permeabilization. Moreover, brief exposures to ATP were sufficient to induce apoptosis in BMMCs, MC/9, and P815 cells which involved activation of caspase-3 and -8. However, in the time period between commitment to apoptosis and actual cell death, ATP triggered rapid but transient phosphorylation of multiple signaling molecules in BMMCs and MC/9 cells, including ERK, Jak2, and STAT6. In addition, ATP stimulation enhanced the expression of several proinflammatory cytokines, such as IL-4, IL-6, IL-13, and TNF-alpha. The effects of ATP were mimicked by submillimolar concentrations of 3-O-(4'-benzoyl)-benzoyl-benzoyl-ATP, and were inhibited by pretreatment of mast cells with a selective blocker of human and mouse P2X(7) receptor, 1[N,O-bis(5-isoquinolinesulphonyl)-N-methyl-l-tyrosyl]-4-phenylpiperazine, as well as oxidized ATP. The nucleotide selectivity and pharmacological profile data support the role for P2X(7) receptor as the mediator of the ATP-induced responses. Given the importance of mast cells in diverse pathological conditions, the ability of extracellular ATP to induce the P2X(7)-mediated apoptosis in these cells may facilitate the development of new strategies to modulate mast cell activities.
Collapse
|
40
|
Araya R, Riquelme MA, Brandan E, Sáez JC. The formation of skeletal muscle myotubes requires functional membrane receptors activated by extracellular ATP. ACTA ACUST UNITED AC 2005; 47:174-88. [PMID: 15572171 DOI: 10.1016/j.brainresrev.2004.06.003] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/08/2004] [Indexed: 10/26/2022]
Abstract
Skeletal muscle differentiation follows an organized sequence of events including commitment, cell cycle withdrawal, and cell fusion to form multinucleated myotubes. The role of adenosine 5'-triphosphate (ATP)-mediated signaling in differentiation of skeletal muscle myoblasts was evaluated in C(2)C(12) cells, a myoblast cell line. Cell differentiation was inhibited by P2X receptor blockers or by degradation of endogenous ATP with apyrase. However, pertussis toxin, known to block only a group of P2Y receptors, did not alter the differentiation process. Cells were heterogeneous in their expression of functional P2X receptors, evaluated by the uptake of fluorescent permeability tracers (Lucifer yellow and ethidium bromide), and by immunofluorescence of P2X(7) receptors. Moreover, xestospongin C, a selective and membrane-permeable inhibitor of IP(3) receptors, inhibited both myotube formation and myogenin expression. Based on these results, we suggest that the known increase in intracellular Ca(2+) concentration required for differentiation is due at least in part to Ca(2+) influx through P2X receptors and Ca(2+) release from intracellular stores. The possible involvement of P2X receptors and other pathways that might set the intracellular Ca(2+) at the level required for myoblast differentiation as well as the possible involvement of gap junction channels in the intercellular transfer of second messengers involved in coordinating myogenesis is proposed.
Collapse
MESH Headings
- Adenosine Triphosphate/metabolism
- Animals
- Calcium/metabolism
- Calcium Channels/metabolism
- Calcium Signaling/drug effects
- Calcium Signaling/physiology
- Cell Differentiation/drug effects
- Cell Differentiation/physiology
- Cell Line
- Extracellular Fluid/metabolism
- Fluorescent Dyes/metabolism
- Gap Junctions/metabolism
- Inositol 1,4,5-Trisphosphate Receptors
- Intracellular Fluid/drug effects
- Intracellular Fluid/metabolism
- Mice
- Muscle Fibers, Skeletal/metabolism
- Muscle, Skeletal/drug effects
- Muscle, Skeletal/growth & development
- Muscle, Skeletal/metabolism
- Myogenin/biosynthesis
- Myogenin/drug effects
- Purinergic P2 Receptor Antagonists
- Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors
- Receptors, Cytoplasmic and Nuclear/metabolism
- Receptors, Purinergic P2/metabolism
- Receptors, Purinergic P2X
- Receptors, Purinergic P2X7
- Sarcolemma/metabolism
Collapse
Affiliation(s)
- Roberto Araya
- Departamento de Ciencias Fisiológicas, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, Region Metropolitana, Santiago 114D, Chile.
| | | | | | | |
Collapse
|
41
|
Palaga T, Kataoka T, Nagai K. Extracellular ATP inhibits apoptosis and maintains cell viability by inducing autocrine production of interleukin-4 in a myeloid progenitor cell line. Int Immunopharmacol 2005; 4:953-61. [PMID: 15182734 DOI: 10.1016/j.intimp.2004.04.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2004] [Revised: 02/03/2004] [Accepted: 04/09/2004] [Indexed: 11/23/2022]
Abstract
Interleukin-3 (IL-3)-dependent myeloid progenitor cell FDC.P2 is induced to undergo apoptotic cell death upon IL-3 depletion. Extracellular adenosine triphosphate (ATP) was found to prevent apoptosis and maintain cell viability of FDC.P2 cells upon IL-3 withdrawal. The antiapoptotic effect of ATP required extracellular Ca2+. Furthermore, FK506, a specific inhibitor of calcium/calmodulin-dependent protein phosphatase calcineurin, inhibited the antiapoptotic effect of ATP. As one of cytokines whose expression is dependent on the activation of calcineurin, interleukin-4 (IL-4) played a critical role in ATP-mediated cell survival of FDC.P2 cells because neutralizing antibody against IL-4 effectively abrogated the antiapoptotic activity of ATP. Moreover, ATP treatment induced a significant amount of secreted IL-4 that was sufficient to maintain cell viability. Taken together, our present results demonstrate that extracellular ATP triggers autocrine production of IL-4 through calcium-dependent activation of calcineurin and secreted IL-4 substitutes IL-3 in protecting FDC.P2 cells from apoptosis even in the absence of IL-3.
Collapse
Affiliation(s)
- Tanapat Palaga
- Department of Bioengineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori, Yokohama 226, Japan.
| | | | | |
Collapse
|
42
|
Burnstock G, Knight GE. Cellular Distribution and Functions of P2 Receptor Subtypes in Different Systems. INTERNATIONAL REVIEW OF CYTOLOGY 2004; 240:31-304. [PMID: 15548415 DOI: 10.1016/s0074-7696(04)40002-3] [Citation(s) in RCA: 573] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review is aimed at providing readers with a comprehensive reference article about the distribution and function of P2 receptors in all the organs, tissues, and cells in the body. Each section provides an account of the early history of purinergic signaling in the organ?cell up to 1994, then summarizes subsequent evidence for the presence of P2X and P2Y receptor subtype mRNA and proteins as well as functional data, all fully referenced. A section is included describing the plasticity of expression of P2 receptors during development and aging as well as in various pathophysiological conditions. Finally, there is some discussion of possible future developments in the purinergic signaling field.
Collapse
Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Institute, Royal Free and University College Medical School, London NW3 2PF, United Kingdom
| | | |
Collapse
|
43
|
Cheng X, Wang C, Qian G, Zhu B. CD80, but not CD86 were up-regulated on the spleen-derived dendritic cells from OVA-sensitized and challenged BALB/c mice. Immunol Lett 2003; 89:31-8. [PMID: 12946862 DOI: 10.1016/s0165-2478(03)00107-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Allergen-specific CD4+ T-helper (Th) 2 cells are involved in the induction and effector phase of allergic asthma. It is well established that T cells activation requires interaction of T cell receptor (TCR) and MHC-peptide complex, as well as costimulatory signal delivered by antigen presenting cells (APCs). There is increasing evidence that CD80 (B7.1) and CD86 (B7.2), as the most important costimulatory molecules, are involved in the allergic immune responses. In the present study, we investigated the CD80 and CD86 expression of spleen-derived dendritic cells (DCs) in a murine model of allergic asthma. We first established a murine model of ovalbumin (OVA)-allergic asthma that showed unique histological characteristic of allergic inflammation in the lung, high serum OVA-specific IgE level, high numbers of eosinophils in the bronchoalveolar lavage (BAL) and high production of Type 2 cytokines in the splenic T cells. In this model, we found that CD80 were significantly upregulated on the spleen-derived DCs from OVA-sensitized and challenged mice compared with that from PBS-treated or non-treated mice, while CD86 is not different among three groups. Furthermore, we demonstrated that Th2 immune responses were elicited by these DCs with high expression of CD80, even to nai;ve T cells from non-treated mice. Our results suggest that DCs in the spleen of allergic mice, via upregulation of CD80 might play a pivotal role in the maintenance and amplification of allergic immune response, namely Th2 immune response.
Collapse
Affiliation(s)
- Xiaoming Cheng
- Institute of Respiratory Diseases, Xinqiao Hospital, Third Military Medical University, Chongqing 400037, PR China.
| | | | | | | |
Collapse
|
44
|
Wen LT, Caldwell CC, Knowles AF. Poly(ADP-ribose) polymerase activation and changes in Bax protein expression associated with extracellular ATP-mediated apoptosis in human embryonic kidney 293-P2X7 cells. Mol Pharmacol 2003; 63:706-13. [PMID: 12606781 DOI: 10.1124/mol.63.3.706] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Extracellular ATP is a potent signaling factor that modulates a variety of cellular functions through the activation of P2 purinergic receptors. Extracellular ATP at higher concentrations exerts cytostatic as well as cytotoxic effects in a variety of cell systems, the mechanism of which is not fully understood. In this study, we used cultured human embryonic kidney (HEK) cells stably transfected with human P2X(7) receptors (HEK-P2X(7)) to investigate the mechanism of ATP-induced cell death. The cytotoxic effects of ATP in HEK-P2X(7) cells were dose- and time-dependent, whereas ADP, AMP, and UTP had no effect. ATP treatment induced a significant increase in apoptotic HEK-P2X(7) cells as ascertained by the terminal deoxynucleotidyl transferase dUTP nick-end labeling technique and flow cytometry. An ATP-induced decrease in the pro-apoptotic bax gene expression was detected by apoptosis-related cDNA microarray analysis, which correlated with a decrease of Bax protein expression. Western blot analysis revealed that ATP treatment resulted in the processing of pro-caspase 3 to its active form and cleavage of the nuclear enzyme, poly(ADP-ribose) polymerase (PARP). Both ATP-induced molecular alterations in HEK-P2X(7) cells (i.e., decrease of Bax expression and increase of PARP cleavage) were blocked by the purinergic P2X(7) receptor antagonist oxidized ATP. In conclusion, we demonstrated the importance of the P2X(7) receptor in ATP induced cell death of HEK-P2X(7) cells, which seems to be independent of bax expression; however, the activation of caspases is required.
Collapse
Affiliation(s)
- Long T Wen
- Microchemical Core Facility, Department of Biology, San Diego State University, San Diego, California 92182-1030, USA.
| | | | | |
Collapse
|
45
|
Idzko M, Dichmann S, Ferrari D, Di Virgilio F, la Sala A, Girolomoni G, Panther E, Norgauer J. Nucleotides induce chemotaxis and actin polymerization in immature but not mature human dendritic cells via activation of pertussis toxin-sensitive P2y receptors. Blood 2002; 100:925-32. [PMID: 12130504 DOI: 10.1182/blood.v100.3.925] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dendritic cells (DCs) are considered the principal initiators of immune response because of their ability to migrate into peripheral tissues and lymphoid organs, process antigens, and activate naive T cells. There is evidence that extracellular nucleotides regulate certain functions of DCs via G-protein-coupled P2Y receptors (P2YR) and ion-channel-gated P2X receptors (P2XR). Here we investigated the chemotactic activity and analyzed the migration-associated intracellular signaling events such as actin reorganization and Ca(++) transients induced by common P2R agonists such as adenosine 5'-triphosphate (ATP) and 2-methylthioadenosine triphosphate, the P2YR agonists UTP and adenosine 5'-diphosphate (ADP), or the P2XR agonists alphabeta-methylenadenosine-5'-triphosphate and 2',3'-(4-benzoyl)benzoyl-ATP. The common P2R agonists and the selective P2YR agonists turned out to be potent chemotactic stimuli for immature DCs, but not for mature DCs. In contrast, P2XR agonists had only marginal chemotactic activity in both DC types. Chemotaxis was paralleled by a rise in the intracellular Ca(++) concentration and by actin polymerization. Studies with pertussis toxin implicated that intracellular signaling events such as actin polymerization, mobilization of intracellular Ca(++), and migration induced by nucleotides was mediated via G(i/o) protein-coupled P2YR. Moreover, functional studies revealed selective down-regulation of this G(i/o) protein-coupled chemotactic P2YR responsiveness during maturation, although immature and mature DCs expressed similar amounts of mRNA for the P2R subtypes (P2Y(2)R, P2Y(4)R, P2Y(5)R, P2Y(7)R, P2Y(11)R and P2X(1)R, P2X(4)R, P2X(7)R), and no major differences in respect to the mRNA expression of these receptors could be observed by semiquantitative reverse transcription and polymerase chain reaction (RT-PCR). In summary, our data describe a differential chemotactic response of immature and mature DCs to nucleotides, and lend further support to the hypothesis that P2R are a novel class of immunomodulatory plasma membrane receptors suitable for pharmacological intervention.
Collapse
Affiliation(s)
- Marco Idzko
- Department of Experimental Dermatology, University of Freiburg, Germany
| | | | | | | | | | | | | | | |
Collapse
|
46
|
Mizumoto N, Kumamoto T, Robson SC, Sévigny J, Matsue H, Enjyoji K, Takashima A. CD39 is the dominant Langerhans cell-associated ecto-NTPDase: modulatory roles in inflammation and immune responsiveness. Nat Med 2002; 8:358-65. [PMID: 11927941 DOI: 10.1038/nm0402-358] [Citation(s) in RCA: 269] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
CD39, the endothelial ecto-nucleoside triphosphate diphosphohydrolase (NTPDase), regulates vascular inflammation and thrombosis by hydrolyzing ATP and ADP. Although ecto-NTPDase activities have been used as a marker of epidermal dendritic cells (DCs) known as Langerhans cells, the identity and function of these activities remain unknown. Here we report that Langerhans cells in CD39-/- mice express no detectable ecto-NTPDase activity. Irritant chemicals triggered rapid ATP and ADP release from keratinocytes and caused exacerbated skin inflammation in CD39-/- mice. Paradoxically, T cell-mediated allergic contact hypersensitivity was severely attenuated in CD39-/- mice. As to mechanisms, T cells increased pericellular ATP concentrations upon activation, and CD39-/- DCs showed ATP unresponsiveness (secondary to P2-receptor desensitization) and impaired antigen-presenting capacity. Our results show opposing outcomes of CD39 deficiency in irritant versus allergic contact dermatitis, reflecting its diverse roles in regulating extracellular nucleotide-mediated signaling in inflammatory responses to environmental insults and DC-T cell communication in antigen presentation.
Collapse
Affiliation(s)
- Norikatsu Mizumoto
- Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | | | | | | | | | | | | |
Collapse
|
47
|
Wiley JS, Dao-Ung LP, Gu BJ, Sluyter R, Shemon AN, Li C, Taper J, Gallo J, Manoharan A. A loss-of-function polymorphic mutation in the cytolytic P2X7 receptor gene and chronic lymphocytic leukaemia: a molecular study. Lancet 2002; 359:1114-9. [PMID: 11943260 DOI: 10.1016/s0140-6736(02)08156-4] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Chronic lymphocytic leukaemia (CLL) has a familial incidence nearly three times higher than expected for the general population and one predisposing factor might be an inherited failure of mechanisms involved in apoptosis of lymphocytes. Our aim was to ascertain whether or not a defect in a proapoptotic pathway, caused by a single nucleotide polymorphism that results in loss-of-function of P2X7 in healthy individuals, was present in leukaemic B lymphocytes of patients with CLL. METHODS We extracted genomic DNA from the peripheral blood leucocytes of 36 unrelated individuals with CLL, four individuals with familial CLL, and 46 age-matched controls. We sequenced a PCR product to detect mutations in exon 13 of P2X7. In most patients with CLL, we measured expression and function of the P2X7 receptor by flow cytometry in B lymphocytes and T lymphocytes. FINDINGS The prevalence of the polymorphic mutation and the frequency of the mutant allele were three-fold greater in individuals with CLL than in white, elderly controls. Individuals homozygous for the polymorphic allele had no P2X7 receptor function and heterozygotes had half the mean function of that seen in individuals homozygous for the wildtype allele; amounts of ATP-induced apoptosis varied accordingly. In two families, in which we studied a father-son pair and a sister-sister pair with CLL, loss of P2X7 function arose because of inheritance of one or two 1513A-->C alleles for P2X7. INTERPRETATION Activation of the P2X7 receptor leads to apoptosis of lymphocytes in individuals with CLL, and reduced function of this receptor has an anti-apoptotic effect, resulting in an increase in B-cell numbers. Thus, inheritance of a loss-of-function polymorphic mutation at position 1513 in the P2X7 gene could contribute to the pathogenesis of CLL.
Collapse
MESH Headings
- Aged
- Alleles
- Apoptosis/genetics
- B-Lymphocytes/immunology
- Cytotoxicity, Immunologic
- Female
- Gene Expression Regulation, Leukemic
- Heterozygote
- Homozygote
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/physiopathology
- Male
- Middle Aged
- Pedigree
- Point Mutation
- Polymerase Chain Reaction
- Polymorphism, Genetic
- Receptors, Purinergic P2/genetics
- Receptors, Purinergic P2/physiology
- Receptors, Purinergic P2X7
Collapse
Affiliation(s)
- James S Wiley
- Sydney University Department of Medicine, Nepean Hospital, PO Box 63, New South Wales, 2751, Penrith, Australia.
| | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Schrier SM, Florea BI, Mulder GJ, Nagelkerke JF, IJzerman AP. Apoptosis induced by extracellular ATP in the mouse neuroblastoma cell line N1E-115: studies on involvement of P2 receptors and adenosine. Biochem Pharmacol 2002; 63:1119-26. [PMID: 11931844 DOI: 10.1016/s0006-2952(01)00939-x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Adenosine triphosphate (ATP) can be released in large amounts from (damaged) cells, leading to locally high concentrations. In this study, we investigated the effect of such high concentrations of ATP on neuroblastoma cells. ATP (>or=30 microM) induced apoptosis in the mouse neuroblastoma cell line N1E-115. Activation of the ATP receptor P2X(7) is one of the routes via which ATP has been shown to induce apoptosis. Although the P2X(7) receptor was present in N1E-115 cells, both at the protein and mRNA level, studies with the P2X(7) receptor agonist benzoyl-benzoyl ATP showed that this receptor was not involved in ATP-induced apoptosis. It has been shown previously that adenosine induces apoptosis in N1E-115 cells after transport inside the cell. In this study, both dipyridamole, a nucleoside transport protein blocker, and uridine, a substrate for this transporter, were able to block ATP-induced apoptosis. This indicated that ATP had to be broken down to adenosine to induce apoptosis. The ecto-nucleotidase inhibitors 6-N,N-diethyl-beta-dibromomethylene-D-adenosine-5'-triphosphate (ARL67156) and alpha,beta-methylene adenosine 5'-diphosphate (AOPCP) commonly used to slow breakdown of ATP did not inhibit ATP breakdown appreciably, while the ATP antagonist PPADS inhibited the breakdown of AMP to adenosine; PPADS was also the only compound capable of inhibiting ATP-induced apoptosis. We conclude that the main route of ATP-induced apoptosis in N1E-115 cells was via breakdown to adenosine.
Collapse
Affiliation(s)
- S Mariëtte Schrier
- Department of Toxicology, Leiden/Amsterdam Center for Drug Research, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | | | | | | | | |
Collapse
|
49
|
Amadio S, D'Ambrosi N, Cavaliere F, Murra B, Sancesario G, Bernardi G, Burnstock G, Volonté C. P2 receptor modulation and cytotoxic function in cultured CNS neurons. Neuropharmacology 2002; 42:489-501. [PMID: 11955520 DOI: 10.1016/s0028-3908(01)00197-6] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In this study we investigate the presence, modulation and biological function of P2 receptors and extracellular ATP in cultured cerebellar granule neurons. As we demonstrate by RT-PCR and western blotting, both P2X and P2Y receptor subtypes are expressed and furthermore regulated as a function of neuronal maturation. In early primary cultures, mRNA for most of the P2 receptor subtypes, except P2X(6), are found, while in older cultures only P2X(3), P2Y(1) and P2Y(6) mRNA persist. In contrast, P2 receptor proteins are more prominent in mature neurons, with the exception of P2Y(1). We also report that extracellular ATP acts as a cell death mediator for fully differentiated and mature granule neurons, for dissociated striatal primary cells and hippocampal organotypic cultures, inducing both apoptotic and necrotic features of degeneration. ATP causes cell death with EC(50) in the 20-50 microM range within few minutes of exposure and with a time lapse of at most two hours. Additional agonists for P2 receptors induce toxic effects, whereas selected antagonists are protective. Cellular swelling, lactic dehydrogenase release and nuclei fragmentation are among the features of ATP-evoked cell death, which also include direct P2 receptor modulation. Comparably to P2 receptor antagonists previously shown preventing glutamate-toxicity, here we report that competitive and non-competitive NMDA receptor antagonists inhibit the detrimental consequences of extracellular ATP. Due to the massive extracellular release of purine nucleotides and nucleosides often occurring during a toxic insult, our data indicate that extracellular ATP can now be included among the potential causes of CNS neurodegenerative events.
Collapse
Affiliation(s)
- S Amadio
- Fondazione Santa Lucia, Via Ardeatina 354, 00179, Rome, Italy
| | | | | | | | | | | | | | | |
Collapse
|
50
|
O'Connell PJ, Klyachko VA, Ahern GP. Identification of functional type 1 ryanodine receptors in mouse dendritic cells. FEBS Lett 2002; 512:67-70. [PMID: 11852053 DOI: 10.1016/s0014-5793(01)03321-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Ca(2+) signaling plays an important role in the function of dendritic cells (DC), the specialized antigen-presenting cells of the immune system. Here we describe functional ryanodine receptor (RyR) Ca(2+) release channels in murine, bone marrow-derived DC. RT-PCR analysis identified selective expression of the type 1 RyR, with higher levels detected in immature rather than mature DC. The RyR activators caffeine, FK506, ryanodine and 4-chloro-m-cresol mobilized Ca(2+) in DC, and responses to 4-chloro-m-cresol were inhibited by dantrolene. Furthermore, activation of RyRs both inhibited subsequent inositol trisphosphate-mediated Ca(2+) release and provoked store-operated Ca(2+) entry, suggesting a functional interaction between these intracellular Ca(2+) channels. Thus, the RyR1 channel may play an intrinsic role in Ca(2+) signaling in DC.
Collapse
|