1
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Wang X, Wang WX. Tracking the Cellular Degradation of Silver Nanoparticles: Development of a Generic Kinetic Model. ACS NANO 2024; 18:13308-13321. [PMID: 38716827 DOI: 10.1021/acsnano.4c03032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
Understanding the degradation of nanoparticles (NPs) after crossing the cell plasma membrane is crucial in drug delivery designs and cytotoxicity assessment. However, the key factors controlling the degradable kinetics remain unclear due to the absence of a quantification model. In this study, subcellular imaging of silver nanoparticles (AgNPs) was used to determine the intracellular transfer of AgNPs, and single particle ICP-MS was utilized to track the degradation process. A cellular kinetic model was subsequently developed to describe the uptake, transfer, and degradation behaviors of AgNPs. Our model demonstrated that the intracellular degradation efficiency of AgNPs was much higher than that determined by mimicking testing, and the degradation of NPs was highly influenced by cellular factors. Specifically, deficiencies in Ca or Zn primarily decreased the kinetic dissolution of NPs, while a Ca deficiency also resulted in the retardation of NP transfer. The biological significance of these kinetic parameters was strongly revealed. Our model indicated that the majority of internalized AgNPs dissolved, with the resulting ions being rapidly depurated. The release of Ag ions was largely dependent on the microvesicle-mediated route. By changing the coating and size of AgNPs, the model results suggested that size influenced the transfer of NPs into the degradation process, whereas coating affected the degradation kinetics. Overall, our developed model provides a valuable tool for understanding and predicting the impacts of the physicochemical properties of NPs and the ambient environment on nanotoxicity and therapeutic efficacy.
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Affiliation(s)
- Xiangrui Wang
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, China
- Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China
| | - Wen-Xiong Wang
- School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, China
- Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China
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2
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Wang Y, Wakelam MJO, Bankaitis VA, McDermott MI. The wide world of non-mammalian phospholipase D enzymes. Adv Biol Regul 2024; 91:101000. [PMID: 38081756 DOI: 10.1016/j.jbior.2023.101000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 02/25/2024]
Abstract
Phospholipase D (PLD) hydrolyses phosphatidylcholine (PtdCho) to produce free choline and the critically important lipid signaling molecule phosphatidic acid (PtdOH). Since the initial discovery of PLD activities in plants and bacteria, PLDs have been identified in a diverse range of organisms spanning the taxa. While widespread interest in these proteins grew following the discovery of mammalian isoforms, research into the PLDs of non-mammalian organisms has revealed a fascinating array of functions ranging from roles in microbial pathogenesis, to the stress responses of plants and the developmental patterning of flies. Furthermore, studies in non-mammalian model systems have aided our understanding of the entire PLD superfamily, with translational relevance to human biology and health. Increasingly, the promise for utilization of non-mammalian PLDs in biotechnology is also being recognized, with widespread potential applications ranging from roles in lipid synthesis, to their exploitation for agricultural and pharmaceutical applications.
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Affiliation(s)
- Y Wang
- Department of Cell Biology & Genetics, Texas A&M Health Science Center, College Station, TX, 77843, USA; Department of Microbiology, University of Washington, Seattle, WA98109, USA
| | - M J O Wakelam
- Babraham Institute, Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom
| | - V A Bankaitis
- Department of Cell Biology & Genetics, Texas A&M Health Science Center, College Station, TX, 77843, USA; Department of Biochemistry & Biophysics, Texas A&M University, College Station, TX, 77843, USA; Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA
| | - M I McDermott
- Department of Cell Biology & Genetics, Texas A&M Health Science Center, College Station, TX, 77843, USA.
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3
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Biswas VK, Sen K, Ahad A, Ghosh A, Verma S, Pati R, Prusty S, Nayak SP, Podder S, Kumar D, Gupta B, Raghav SK. NCoR1 controls Mycobacterium tuberculosis growth in myeloid cells by regulating the AMPK-mTOR-TFEB axis. PLoS Biol 2023; 21:e3002231. [PMID: 37590294 PMCID: PMC10465006 DOI: 10.1371/journal.pbio.3002231] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 08/29/2023] [Accepted: 07/04/2023] [Indexed: 08/19/2023] Open
Abstract
Mycobacterium tuberculosis (Mtb) defends host-mediated killing by repressing the autophagolysosome machinery. For the first time, we report NCoR1 co-repressor as a crucial host factor, controlling Mtb growth in myeloid cells by regulating both autophagosome maturation and lysosome biogenesis. We found that the dynamic expression of NCoR1 is compromised in human peripheral blood mononuclear cells (PBMCs) during active Mtb infection, which is rescued upon prolonged anti-mycobacterial therapy. In addition, a loss of function in myeloid-specific NCoR1 considerably exacerbates the growth of M. tuberculosis in vitro in THP1 differentiated macrophages, ex vivo in bone marrow-derived macrophages (BMDMs), and in vivo in NCoR1MyeKO mice. We showed that NCoR1 depletion controls the AMPK-mTOR-TFEB signalling axis by fine-tuning cellular adenosine triphosphate (ATP) homeostasis, which in turn changes the expression of proteins involved in autophagy and lysosomal biogenesis. Moreover, we also showed that the treatment of NCoR1 depleted cells by Rapamycin, Antimycin-A, or Metformin rescued the TFEB activity and LC3 levels, resulting in enhanced Mtb clearance. Similarly, expressing NCoR1 exogenously rescued the AMPK-mTOR-TFEB signalling axis and Mtb killing. Overall, our data revealed a central role of NCoR1 in Mtb pathogenesis in myeloid cells.
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Affiliation(s)
- Viplov Kumar Biswas
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
- School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, India
| | - Kaushik Sen
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
- Regional Centre for Biotechnology, Faridabad, India
| | - Abdul Ahad
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
| | - Arup Ghosh
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
- School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, India
| | - Surbhi Verma
- Molecular Medicine: Cellular Immunology, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Rashmirekha Pati
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
| | - Subhasish Prusty
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
- Regional Centre for Biotechnology, Faridabad, India
| | - Sourya Prakash Nayak
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
| | - Sreeparna Podder
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
- School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, India
| | - Dhiraj Kumar
- Molecular Medicine: Cellular Immunology, International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Bhawna Gupta
- School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, India
| | - Sunil Kumar Raghav
- Immuno-genomics & Systems Biology Laboratory, Institute of Life Sciences (ILS), Bhubaneswar, India
- School of Biotechnology, Kalinga Institute of Industrial Technology (KIIT), Bhubaneswar, India
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Macrophage NFATC2 mediates angiogenic signaling during mycobacterial infection. Cell Rep 2022; 41:111817. [PMID: 36516756 PMCID: PMC9880963 DOI: 10.1016/j.celrep.2022.111817] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 11/05/2022] [Accepted: 11/21/2022] [Indexed: 12/15/2022] Open
Abstract
During mycobacterial infections, pathogenic mycobacteria manipulate both host immune and stromal cells to establish and maintain a productive infection. In humans, non-human primates, and zebrafish models of infection, pathogenic mycobacteria produce and modify the specialized lipid trehalose 6,6'-dimycolate (TDM) in the bacterial cell envelope to drive host angiogenesis toward the site of forming granulomas, leading to enhanced bacterial growth. Here, we use the zebrafish-Mycobacterium marinum infection model to define the signaling basis of the host angiogenic response. Through intravital imaging and cell-restricted peptide-mediated inhibition, we identify macrophage-specific activation of NFAT signaling as essential to TDM-mediated angiogenesis in vivo. Exposure of cultured human cells to Mycobacterium tuberculosis results in robust induction of VEGFA, which is dependent on a signaling pathway downstream of host TDM detection and culminates in NFATC2 activation. As granuloma-associated angiogenesis is known to serve bacterial-beneficial roles, these findings identify potential host targets to improve tuberculosis disease outcomes.
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CRISPR Interference Reveals That All- Trans-Retinoic Acid Promotes Macrophage Control of Mycobacterium tuberculosis by Limiting Bacterial Access to Cholesterol and Propionyl Coenzyme A. mBio 2022; 13:e0368321. [PMID: 35038923 PMCID: PMC8764544 DOI: 10.1128/mbio.03683-21] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Macrophages are a protective replicative niche for Mycobacterium tuberculosis (Mtb) but can kill the infecting bacterium when appropriately activated. To identify mechanisms of clearance, we compared levels of bacterial restriction by human macrophages after treatment with 26 compounds, including some currently in clinical trials for tuberculosis. All-trans-retinoic acid (ATRA), an active metabolite of vitamin A, drove the greatest increase in Mtb control. Bacterial clearance was transcriptionally and functionally associated with changes in macrophage cholesterol trafficking and lipid metabolism. To determine how these macrophage changes affected bacterial control, we performed the first Mtb CRISPR interference screen in an infection model, identifying Mtb genes specifically required to survive in ATRA-activated macrophages. These data showed that ATRA treatment starves Mtb of cholesterol and the downstream metabolite propionyl coenzyme A (propionyl-CoA). Supplementation with sources of propionyl-CoA, including cholesterol, abrogated the restrictive effect of ATRA. This work demonstrates that targeting the coupled metabolism of Mtb and the macrophage improves control of infection and that it is possible to genetically map the mode of bacterial death using CRISPR interference. IMPORTANCE Tuberculosis, caused by the bacterium Mycobacterium tuberculosis, is a leading cause of death due to infectious disease. Improving the immune response to tuberculosis holds promise for fighting the disease but is limited by our lack of knowledge as to how the immune system kills M. tuberculosis. Our research identifies a potent way to make relevant immune cells more effective at fighting M. tuberculosis and then uses paired human and bacterial genomic methods to determine the mechanism of that improved bacterial clearance.
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P2X7 receptor in multifaceted cellular signalling and its relevance as a potential therapeutic target in different diseases. Eur J Pharmacol 2021; 906:174235. [PMID: 34097884 DOI: 10.1016/j.ejphar.2021.174235] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/28/2021] [Accepted: 06/02/2021] [Indexed: 02/07/2023]
Abstract
P2X7 receptor, a purinergic receptor family member, is abundantly expressed on many cells, including immune, muscle, bone, neuron, and glia. It acts as an ATP-activated cation channel that permits the influx of Ca2+, Na+ and efflux of K+ ions. The P2X7 receptor plays crucial roles in many physiological processes including cytokine and chemokine secretion, NLRP3 inflammasome activation, cellular growth and differentiation, locomotion, wound healing, transcription factors activation, cell death and T-lymphocyte survival. Past studies have demonstrated the up-regulation and direct association of this receptor in many pathophysiological conditions such as cancer, diabetics, arthritis, tuberculosis (TB) and inflammatory diseases. Hence, targeting this receptor is considered a worthwhile approach to lessen the afflictions associated with the disorders mentioned above by understanding the receptor architecture and downstream signalling processes. Here, in the present review, we have dissected the structural and functional aspects of the P2X7 receptor, emphasizing its role in various diseased conditions. This information will provide in-depth knowledge about the receptor and help to develop apt curative methodologies for the betterment of humanity in the coming years.
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Morgan AJ, Davis LC, Galione A. Choreographing endo-lysosomal Ca 2+ throughout the life of a phagosome. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2021; 1868:119040. [PMID: 33872669 DOI: 10.1016/j.bbamcr.2021.119040] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 04/05/2021] [Accepted: 04/07/2021] [Indexed: 12/20/2022]
Abstract
The emergence of endo-lysosomes as ubiquitous Ca2+ stores with their unique cohort of channels has resulted in their being implicated in a growing number of processes in an ever-increasing number of cell types. The architectural and regulatory constraints of these acidic Ca2+ stores distinguishes them from other larger Ca2+ sources such as the ER and influx across the plasma membrane. In view of recent advances in the understanding of the modes of operation, we discuss phagocytosis as a template for how endo-lysosomal Ca2+ signals (generated via TPC and TRPML channels) can be integrated in multiple sophisticated ways into biological processes. Phagocytosis illustrates how different endo-lysosomal Ca2+ signals drive different phases of a process, and how these can be altered by disease or infection.
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Affiliation(s)
- Anthony J Morgan
- Department of Pharmacology, University of Oxford, Mansfield Park, Oxford OX1 3QT, UK.
| | - Lianne C Davis
- Department of Pharmacology, University of Oxford, Mansfield Park, Oxford OX1 3QT, UK
| | - Antony Galione
- Department of Pharmacology, University of Oxford, Mansfield Park, Oxford OX1 3QT, UK.
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8
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Campagno KE, Mitchell CH. The P2X 7 Receptor in Microglial Cells Modulates the Endolysosomal Axis, Autophagy, and Phagocytosis. Front Cell Neurosci 2021; 15:645244. [PMID: 33790743 PMCID: PMC8005553 DOI: 10.3389/fncel.2021.645244] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 02/22/2021] [Indexed: 01/18/2023] Open
Abstract
Microglial cells regulate neural homeostasis by coordinating both immune responses and clearance of debris, and the P2X7 receptor for extracellular ATP plays a central role in both functions. The P2X7 receptor is primarily known in microglial cells for its immune signaling and NLRP3 inflammasome activation. However, the receptor also affects the clearance of extracellular and intracellular debris through modifications of lysosomal function, phagocytosis, and autophagy. In the absence of an agonist, the P2X7 receptor acts as a scavenger receptor to phagocytose material. Transient receptor stimulation induces autophagy and increases LC3-II levels, likely through calcium-dependent phosphorylation of AMPK, and activates microglia to an M1 or mixed M1/M2 state. We show an increased expression of Nos2 and Tnfa and a decreased expression of Chil3 (YM1) from primary cultures of brain microglia exposed to high levels of ATP. Sustained stimulation can reduce lysosomal function in microglia by increasing lysosomal pH and slowing autophagosome-lysosome fusion. P2X7 receptor stimulation can also cause lysosomal leakage, and the subsequent rise in cytoplasmic cathepsin B activates the NLRP3 inflammasome leading to caspase-1 cleavage and IL-1β maturation and release. Support for P2X7 receptor activation of the inflammasome following lysosomal leakage comes from data on primary microglia showing IL-1β release following receptor stimulation is inhibited by cathepsin B blocker CA-074. This pathway bridges endolysosomal and inflammatory roles and may provide a key mechanism for the increased inflammation found in age-dependent neurodegenerations characterized by excessive lysosomal accumulations. Regardless of whether the inflammasome is activated via this lysosomal leakage or the better-known K+-efflux pathway, the inflammatory impact of P2X7 receptor stimulation is balanced between the autophagic reduction of inflammasome components and their increase following P2X7-mediated priming. In summary, the P2X7 receptor modulates clearance of extracellular debris by microglial cells and mediates lysosomal damage that can activate the NLRP3 inflammasome. A better understanding of how the P2X7 receptor alters phagocytosis, lysosomal health, inflammation, and autophagy can lead to therapies that balance the inflammatory and clearance roles of microglial cells.
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Affiliation(s)
- Keith E Campagno
- Department of Basic and Translational Science, University of Pennsylvania, Philadelphia, PA, United States
| | - Claire H Mitchell
- Department of Basic and Translational Science, University of Pennsylvania, Philadelphia, PA, United States.,Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA, United States.,Department of Physiology, University of Pennsylvania, Philadelphia, PA, United States
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9
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Coutinho-Silva R, Savio LEB. Purinergic signalling in host innate immune defence against intracellular pathogens. Biochem Pharmacol 2021; 187:114405. [PMID: 33406411 DOI: 10.1016/j.bcp.2021.114405] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 12/29/2020] [Accepted: 12/31/2020] [Indexed: 02/07/2023]
Abstract
Purinergic signalling is an evolutionarily conserved signalling pathway mediated by extracellular nucleotides and nucleosides. Tri- and diphosphonucleotides released from host cells during intracellular pathogen infections activate plasma membrane purinergic type 2 receptors (P2 receptors) that stimulate microbicidal mechanisms in host innate immune cells. P2X ion channels and P2Y G protein-coupled receptors are involved in activating host innate immune defence mechanisms, phagocytosis, phagolysosomal fusion, production of reactive species, acidification of parasitophorous vacuoles, inflammasome activation, and the release of cytokines, chemokines, and other inflammatory mediators. In this review, as part of a special issue in tribute to Geoffrey Burnstock, we discuss advances in understanding the importance of P2 receptors in the host antimicrobial innate mechanisms against intracellular pathogen infections.
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Affiliation(s)
- Robson Coutinho-Silva
- Laboratory of Immunophysiology, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
| | - Luiz Eduardo Baggio Savio
- Laboratory of Immunophysiology, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.
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Restrepo BI, Khan A, Singh VK, Erica de-Leon, Aguillón-Durán GP, Ledezma-Campos E, Canaday DH, Jagannath C. Human monocyte-derived macrophage responses to M. tuberculosis differ by the host's tuberculosis, diabetes or obesity status, and are enhanced by rapamycin. Tuberculosis (Edinb) 2021; 126:102047. [PMID: 33418150 PMCID: PMC7887072 DOI: 10.1016/j.tube.2020.102047] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Revised: 11/17/2020] [Accepted: 12/23/2020] [Indexed: 02/06/2023]
Abstract
Human macrophages play a major role in controlling tuberculosis (TB), but their anti-mycobacterial mechanisms remain unclear among individuals with metabolic alterations like obesity (TB protective) or diabetes (TB risk). To help discern this, we aimed to: i) Evaluate the impact of the host's TB status or their comorbidities on the anti-mycobacterial responses of their monocyte-derived macrophages (MDMs), and ii) determine if the autophagy inducer rapamycin, can enhance these responses. We used MDMs from newly diagnosed TB patients, their close contacts and unexposed controls. The MDMs from TB patients had a reduced capacity to activate T cells (surrogate for antigen presentation) or kill M. tuberculosis (Mtb) when compared to non-TB controls. The MDMs from obese participants had a higher antigen presenting capacity, whereas those from chronic diabetes patients displayed lower Mtb killing. The activation of MDMs with rapamycin led to an enhanced anti-mycobacterial activity irrespective of TB status but was not as effective in patients with diabetes. Further studies are warranted using MDMs from TB patients with or without metabolic comorbidities to: i) elucidate the mechanisms through which host factors affect Mtb responses, and ii) evaluate host directed therapy using autophagy-inducing drugs like rapamycin to enhance macrophage function.
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Affiliation(s)
- Blanca I Restrepo
- University of Texas Health Houston, School of Public Health, One West University Blvd, Brownsville, TX, USA; University of Texas Rio Grande Valley, School of Medicine, South Texas Diabetes and Obesity Institute, 1214 W Schunior, Edinburg, TX, USA.
| | - Arshad Khan
- Houston Methodist Research Institute, Houston, Weill-Cornell Medicine, TX, USA.
| | - Vipul K Singh
- Houston Methodist Research Institute, Houston, Weill-Cornell Medicine, TX, USA.
| | - Erica de-Leon
- University of Texas Health Houston, School of Public Health, One West University Blvd, Brownsville, TX, USA.
| | - Génesis P Aguillón-Durán
- University of Texas Health Houston, School of Public Health, One West University Blvd, Brownsville, TX, USA; Secretaria de Salud de Tamaulipas, Reynosa and Ciudad Victoria, Mexico.
| | | | - David H Canaday
- Division of Infectious Disease, Case Western Reserve University and Cleveland, VA, OH, USA.
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Dahiya P, Datta D, Hussain MA, Verma G, Shelly A, Mehta P, Mazumder S. The coordinated outcome of STIM1-Orai1 and superoxide signalling is crucial for headkidney macrophage apoptosis and clearance of Mycobacterium fortuitum. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 114:103800. [PMID: 32771347 DOI: 10.1016/j.dci.2020.103800] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/10/2020] [Accepted: 07/10/2020] [Indexed: 06/11/2023]
Abstract
The mechanisms underlying M. fortuitum-induced pathogenesis remains elusive. Using headkidney macrophages (HKM) from Clarias gariepinus, we report that TLR-2-mediated internalization of M. fortuitum is imperative to the induction of pathogenic effects. Inhibiting TLR-2 signalling alleviated HKM apoptosis, thereby favouring bacterial survival. Additionally, TLR-2-mediated cytosolic calcium (Ca2+)c elevation was instrumental for eliciting ER-stress in infected HKM. ER-stress triggered the activation of membrane-proximal calcium entry channels comprising stromal interaction molecule 1 (STIM1) and calcium-release activated calcium channel 1 (Orai1). RNAi studies suggested STIM1-Orai1 signalling initiate calpain-mediated cleavage of nitric oxide synthase interacting protein, prompting the release of pro-apoptotic nitric oxide. Inhibiting STIM1-Orai1 signalling attenuated superoxide production (O2•-) and vice versa. We conclude, TLR-2-induced ER-stress triggers STIM1/Orai1 expression and that the reciprocal association between STIM1-Orai1 signalling and oxidative stress is critical for sustaining (Ca2+)c level, thereby prolonging ER-stress and maintenance of pro-oxidant rich environment to induce HKM apoptosis and bacterial clearance.
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Affiliation(s)
- Priyanka Dahiya
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, 110 007, India
| | - Debika Datta
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, 110 007, India
| | - Md Arafat Hussain
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, 110 007, India
| | - Gaurav Verma
- Lund University of Diabetes Centre, Lund University, Sweden, 21428, Malmo, Sweden
| | - Asha Shelly
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, 110 007, India
| | - Priyanka Mehta
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, 110 007, India
| | - Shibnath Mazumder
- Immunobiology Laboratory, Department of Zoology, University of Delhi, Delhi, 110 007, India; Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, 110 021, India.
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Mukherjee K, Khatua B, Mandal C. Sialic Acid-Siglec-E Interactions During Pseudomonas aeruginosa Infection of Macrophages Interferes With Phagosome Maturation by Altering Intracellular Calcium Concentrations. Front Immunol 2020; 11:332. [PMID: 32184783 PMCID: PMC7059019 DOI: 10.3389/fimmu.2020.00332] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 02/10/2020] [Indexed: 11/24/2022] Open
Abstract
Pseudomonas aeruginosa (PA) is commonly associated with nosocomial and chronic infections of lungs. We have earlier demonstrated that an acidic sugar, sialic acid, is present in PA which is recognized and bound by sialic acid binding immunoglobulin type lectins (siglecs) expressed on neutrophils. Here, we have tried to gain a detailed insight into the immunosuppressive role of sialic acid-siglec interactions in macrophage-mediated clearance of sialylated PA (PA+Sia). We have demonstrated that PA+Sia shows enhanced binding (~1.5-fold) to macrophages due to additional interactions between sialic acids and siglec-E and exhibited more phagocytosis. However, internalization of PA+Sia is associated with a reduction in respiratory burst and increase in anti-inflammatory cytokines secretion which is reversed upon desialylation of the bacteria. Phagocytosis of PA+Sia is also associated with reduced intracellular calcium ion concentrations and altered calcium-dependent signaling which negatively affects phagosome maturation. Consequently, although more PA+Sia was localized in early phagosomes (Rab5 compartment), only fewer bacteria reach into the late phagosomal compartment (Rab7). Possibly, this leads to reduced phagosome lysosome fusion where reduced numbers of PA+Sia are trafficked into lysosomes, compared to PA−Sia. Thus, internalized PA+Sia remain viable and replicates intracellularly in macrophages. We have also demonstrated that such siglec-E-sialic acid interaction recruited SHP-1/SHP-2 phosphatases which modulate MAPK and NF-κB signaling pathways. Disrupting sialic acid-siglec-E interaction by silencing siglec-E in macrophages results in improved bactericidal response against PA+Sia characterized by robust respiratory burst, enhanced intracellular calcium levels and nuclear translocation of p65 component of NF-κB complex leading to increased pro-inflammatory cytokine secretion. Taken together, we have identified that sialic acid-siglec-E interactions is another pathway utilized by PA in order to suppress macrophage antimicrobial responses and inhibit phagosome maturation, thereby persisting as an intracellular pathogen in macrophages.
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Affiliation(s)
- Kaustuv Mukherjee
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Biswajit Khatua
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
| | - Chitra Mandal
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, Kolkata, India
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Molecular Mechanisms of Calcium Signaling During Phagocytosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1246:103-128. [PMID: 32399828 DOI: 10.1007/978-3-030-40406-2_7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Calcium (Ca2+) is a ubiquitous second messenger involved in the regulation of numerous cellular functions including vesicular trafficking, cytoskeletal rearrangements and gene transcription. Both global as well as localized Ca2+ signals occur during phagocytosis, although their functional impact on the phagocytic process has been debated. After nearly 40 years of research, a consensus may now be reached that although not strictly required, Ca2+ signals render phagocytic ingestion and phagosome maturation more efficient, and their manipulation make an attractive avenue for therapeutic interventions. In the last decade many efforts have been made to identify the channels and regulators involved in generating and shaping phagocytic Ca2+ signals. While molecules involved in store-operated calcium entry (SOCE) of the STIM and ORAI family have taken center stage, members of the canonical, melastatin, mucolipin and vanilloid transient receptor potential (TRP), as well as purinergic P2X receptor families are now recognized to play significant roles. In this chapter, we review the recent literature on research that has linked specific Ca2+-permeable channels and regulators to phagocytic function. We highlight the fact that lipid mediators are emerging as important regulators of channel gating and that phagosomal ionic homeostasis and Ca2+ release also play essential parts. We predict that improved methodologies for measuring these factors will be critical for future advances in dissecting the intricate biology of this fascinating immune process.
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Abstract
Macrophages are well known for their phagocytic activity and their role in innate immune responses. Macrophages eat non-self particles, via a variety of mechanisms, and typically break down internalized cargo into small macromolecules. However, some pathogenic agents have the ability to evade this endosomal degradation through a nonlytic exocytosis process termed vomocytosis. Macrophages are well known for their phagocytic activity and their role in innate immune responses. Macrophages eat non-self particles, via a variety of mechanisms, and typically break down internalized cargo into small macromolecules. However, some pathogenic agents have the ability to evade this endosomal degradation through a nonlytic exocytosis process termed vomocytosis. This phenomenon has been most often studied for Cryptococcus neoformans, a yeast that causes roughly 180,000 deaths per year, primarily in immunocompromised (e.g., human immunodeficiency virus [HIV]) patients. Existing dogma purports that vomocytosis involves distinctive cellular pathways and intracellular physicochemical cues in the host cell during phagosomal maturation. Moreover, it has been observed that the immunological state of the individual and macrophage phenotype affect vomocytosis outcomes. Here we compile the current knowledge on the factors (with respect to the phagocytic cell) that promote vomocytosis of C. neoformans from macrophages.
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Watermeyer GA, Locketz M. CD73 expression in tissue granulomas in distinguishing intestinal tuberculosis from Crohn's disease in a South African cohort. Scand J Gastroenterol 2019; 53:1217-1221. [PMID: 30295112 DOI: 10.1080/00365521.2018.1503326] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Overlap of clinical, endoscopic and radiographic features, coupled with a poor microbiological yield makes differentiating Crohn's disease (CD) from intestinal tuberculosis (ITB) challenging. A potential histological differentiating mechanism is the use of immunohistochemical staining for the mesenchymal stem cell marker CD73, as a pilot study showed ITB but not CD granulomas stained positive for this marker. The aim of this study was to assess the value of CD73 in differentiating ITB from CD granulomas in a South African cohort. METHODS Patients with confirmed CD or ITB were identified from a pathology database. Tissue sections were reviewed by a pathologist to confirm the presence of granulomas. These were then stained with a mouse monoclonal anti-CD73 antibody. The slides were examined together by a pathologist and gastroenterologist in a blinded manner for anti-CD73 staining around granulomas. RESULTS Ninety six cases were available for analysis; 50 cases of ITB and 46 cases of CD. Thirty percent of CD granulomas (14/46) stained positive for CD73, whereas CD73 positivity was seen in 52% (26/50) of cases of ITB. This was statistically significant (OR 2.48, 95% CI 1.1-5.72, p = .03). The area under the curve (AUC) was 0.61. Sensitivity of CD73 in predicting ITB was 52% and specificity was 70%. Overall CD73 staining of granulomas correctly classified only 60% of cases. CONCLUSIONS In our study we have shown that significantly more patients with ITB express CD73 in their granulomas than those with CD. However the relatively poor sensitivity, specificity and AUC make this test unlikely to be of value in our clinical practice.
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Affiliation(s)
- Gillian A Watermeyer
- a Division of Gastroenterology, Department of Medicine , Groote Schuur Hospital and University of Cape Town , Cape Town , South Africa
| | - Michael Locketz
- b Division of Anatomical Pathology , National Health Laboratory Service and University of Cape Town , Cape Town , South Africa
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Zhai W, Wu F, Zhang Y, Fu Y, Liu Z. The Immune Escape Mechanisms of Mycobacterium Tuberculosis. Int J Mol Sci 2019; 20:E340. [PMID: 30650615 PMCID: PMC6359177 DOI: 10.3390/ijms20020340] [Citation(s) in RCA: 199] [Impact Index Per Article: 39.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 01/09/2019] [Accepted: 01/09/2019] [Indexed: 01/15/2023] Open
Abstract
Epidemiological data from the Center of Disease Control (CDC) and the World Health Organization (WHO) statistics in 2017 show that 10.0 million people around the world became sick with tuberculosis. Mycobacterium tuberculosis (MTB) is an intracellular parasite that mainly attacks macrophages and inhibits their apoptosis. It can become a long-term infection in humans, causing a series of pathological changes and clinical manifestations. In this review, we summarize innate immunity including the inhibition of antioxidants, the maturation and acidification of phagolysosomes and especially the apoptosis and autophagy of macrophages. Besides, we also elaborate on the adaptive immune response and the formation of granulomas. A thorough understanding of these escape mechanisms is of major importance for the prevention, diagnosis and treatment of tuberculosis.
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Affiliation(s)
- Weijie Zhai
- School of Clinical Medicine, Weifang Medical University, Weifang 261053, China.
| | - Fengjuan Wu
- School of Clinical Medicine, Weifang Medical University, Weifang 261053, China.
| | - Yiyuan Zhang
- School of Clinical Medicine, Weifang Medical University, Weifang 261053, China.
| | - Yurong Fu
- Department of Medical Microbiology, Weifang Medical University, Weifang 261053, China.
| | - Zhijun Liu
- Department of Medical Microbiology, Weifang Medical University, Weifang 261053, China.
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17
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Purinergic receptors in multiple sclerosis pathogenesis. Brain Res Bull 2018; 151:38-45. [PMID: 30500565 DOI: 10.1016/j.brainresbull.2018.11.018] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 11/21/2018] [Accepted: 11/22/2018] [Indexed: 02/08/2023]
Abstract
Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease of the central nervous system, characterized by the presence of focal lesions in white and grey matter with peripheral immune cells infiltration. Purinergic receptors control immune cell function as well as neuronal and oligodendroglial survival, and the activation of astrocytes and microglia, the endogenous brain immune cells. In particular, ionotropic purinergic receptors P2X4 and P2X7 and metabotropic receptor P2Y12 are differently expressed along the disease and their activation or blockage modifies the course of texperimental autoimmune encephalomyelitis (EAE), the dominant animal model of MS. In this review, we will summarize emerging evidence of the role of these three receptor types as potential MS biomarkers and therapeutic targets.
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18
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Paroha R, Chaurasiya SK, Chourasia R. Phospholipase C‐γ2 promotes intracellular survival of mycobacteria. J Cell Biochem 2018; 120:5062-5071. [DOI: 10.1002/jcb.27783] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 09/06/2018] [Indexed: 12/21/2022]
Affiliation(s)
- Ruchi Paroha
- Host‐Pathogen Interaction and Signal Transduction Laboratory, Department of Microbiology, School of Biological Sciences, Dr. Hari Singh Gour University Sagar India
| | - Shivendra K. Chaurasiya
- Host‐Pathogen Interaction and Signal Transduction Laboratory, Department of Microbiology, School of Biological Sciences, Dr. Hari Singh Gour University Sagar India
| | - Rashmi Chourasia
- Department of Chemistry, School of Chemical Sciences, Dr. Hari Singh Gour University Sagar India
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19
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Gu BJ, Wiley JS. P2X7 as a scavenger receptor for innate phagocytosis in the brain. Br J Pharmacol 2018; 175:4195-4208. [PMID: 30098011 DOI: 10.1111/bph.14470] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/20/2018] [Accepted: 07/25/2018] [Indexed: 12/29/2022] Open
Abstract
The P2X7 receptor has been widely studied for its ATP-induced pro-inflammatory effect, but in the absence of a ligand, P2X7 has a second function as a scavenger receptor, which is active in the development of the human brain. The scavenger activity of P2X7 is only evident in the absence of serum but is fully active in cerebrospinal fluid. P2X7 on the cell surface is present as a membrane complex, and an attachment to non-muscle myosin of the cytoskeleton is required for particle engulfment. Selective antagonists of P2X7 pro-inflammatory function have little effect on phagocytosis, but inheritance of a variant haplotype spanning the P2RX7 and P2RX4 genes has been associated with loss of P2X7-mediated phagocytosis. Recent studies in mice suggest that the innate phagocytosis mediated by P2X7 receptors declines with ageing. Thus, defective P2X7-mediated phagocytosis may contribute to age-related neuro-degenerative diseases including Alzheimer's disease, age-related macular degeneration and primary progressive multiple sclerosis.
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Affiliation(s)
- Ben J Gu
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Victoria, Australia
| | - James S Wiley
- The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Melbourne, Victoria, Australia
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20
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Amiri A, Sabooteh T, Ahmadi SAY, Azargoon A, Shahsavar F. Association of P2X7 gene common polymorphisms with pulmonary tuberculosis in Lur population of Iran. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2018. [DOI: 10.1016/j.ejmhg.2017.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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21
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Singh P, Subbian S. Harnessing the mTOR Pathway for Tuberculosis Treatment. Front Microbiol 2018; 9:70. [PMID: 29441052 PMCID: PMC5797605 DOI: 10.3389/fmicb.2018.00070] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Accepted: 01/11/2018] [Indexed: 01/23/2023] Open
Abstract
Tuberculosis (TB) remains as one of the leading killer infectious diseases of humans. At present, the standard therapeutic regimen to treat TB comprised of multiple antibiotics administered for a minimum of six months. Although these drugs are useful in controlling TB burden globally, they have not eliminated the disease. In addition, the lengthy duration of treatment with multiple drugs contributes to patient non-compliance that can result in the development of drug resistant strains (MDR and XDR) of Mycobacterium tuberculosis (Mtb), the causative agent of TB. Therefore, new and improved therapeutic strategies are urgently needed for effective control of TB worldwide. The intracellular survival of Mtb is regarded as a cumulative effect of the host immune response and the bacterial ability to resist or subvert this response. When the host innate defensive system is manipulated by Mtb for its survival and dissemination, the host develops disease conditions that are hard to overcome. The host intrinsic factors also contributes to the poor efficacy of anti-mycobacterial drugs and to the emergence of drug resistance. Hence, strengthening the immune repertoire involved in combating Mtb through host-directed therapeutics (HDT) can be one of the approaches for effective bacterial killing and clearance of infection/disease. Recently, more scientific research has been focused toward HDT strategies that empowers host cells for effective killing of Mtb, reduce the duration of treatment and/or alleviates the development of MDR/XDR, since Mtb cannot develop resistance against a drug that targets the host cell function. Autophagy is a conserved cellular process critical for maintaining cellular integrity and function. Autophagy is regulated by multiple pathways that are either dependent or independent of mTOR (mechanistic target of rapamycin; a.k.a. mammalian target of rapamycin), a master regulatory molecules that impacts several cellular functions. In this review, we summarize the role of autophagy in Mtb pathogenesis, the mTOR pathway and, modulating the mTOR pathway with inhibitors as potential adjunctive HDT, in combination with standard anti-TB antibiotics, to improve the outcome of current TB treatment.
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Affiliation(s)
- Pooja Singh
- Public Health Research Institute at New Jersey Medical School, Rutgers Biomedical and Health Sciences Rutgers, The State University of New Jersey, Newark, NJ, United States
| | - Selvakumar Subbian
- Public Health Research Institute at New Jersey Medical School, Rutgers Biomedical and Health Sciences Rutgers, The State University of New Jersey, Newark, NJ, United States
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22
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Dou L, Chen YF, Cowan PJ, Chen XP. Extracellular ATP signaling and clinical relevance. Clin Immunol 2017; 188:67-73. [PMID: 29274390 DOI: 10.1016/j.clim.2017.12.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 12/12/2017] [Accepted: 12/20/2017] [Indexed: 12/20/2022]
Abstract
Since purinergic signaling was discovered in the early 1970s, it has been shown that extracellular nucleotides, and their derivative nucleosides, are released in a regulated or unregulated manner by cells in various challenging settings and then bind defined purinergic receptors to activate intricate signaling networks. Extracellular ATP plays a role based on different P2 receptor subtypes expressed on specific cell types. Sequential hydrolysis of extracellular ATP catalyzed by ectonucleotidases (e.g. CD39, CD73) is the main pathway for the generation of adenosine, which in turn activates P1 receptors. Many studies have demonstrated that extracellular ATP signaling functions as an important dynamic regulatory pathway to coordinate appropriate immune responses in various pathological processes, including intracellular infection, host-tumor interaction, pro-inflammation vascular injury, and transplant immunity. ATP receptors and CD39 also participate in related clinical settings. Here, we review the latest research in to the development of promising clinical treatment strategies.
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Affiliation(s)
- Lei Dou
- Department of Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Department of Gerontology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yi-Fa Chen
- Department of Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Peter J Cowan
- Immunology Research Centre, St Vincent's Hospital, Melbourne, Australia.
| | - Xiao-Ping Chen
- Department of Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China; Department of Gerontology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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23
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Moreira-Souza ACA, Almeida-da-Silva CLC, Rangel TP, Rocha GDC, Bellio M, Zamboni DS, Vommaro RC, Coutinho-Silva R. The P2X7 Receptor Mediates Toxoplasma gondii Control in Macrophages through Canonical NLRP3 Inflammasome Activation and Reactive Oxygen Species Production. Front Immunol 2017; 8:1257. [PMID: 29075257 PMCID: PMC5643413 DOI: 10.3389/fimmu.2017.01257] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 09/21/2017] [Indexed: 12/12/2022] Open
Abstract
Toxoplasma gondii (T. gondii) is the protozoan parasite that causes toxoplasmosis, a potentially fatal disease to immunocompromised patients, and which affects approximately 30% of the world’s population. Previously, we showed that purinergic signaling via the P2X7 receptor contributes to T. gondii elimination in macrophages, through reactive oxygen species (ROS) production and lysosome fusion with the parasitophorous vacuole. Moreover, we demonstrated that P2X7 receptor activation promotes the production of anti-parasitic pro-inflammatory cytokines during early T. gondii infection in vivo. However, the cascade of signaling events that leads to parasite elimination via P2X7 receptor activation remained to be elucidated. Here, we investigated the cellular pathways involved in T. gondii elimination triggered by P2X7 receptor signaling, during early infection in macrophages. We focused on the potential role of the inflammasome, a protein complex that can be co-activated by the P2X7 receptor, and which is involved in the host immune defense against T. gondii infection. Using peritoneal and bone marrow-derived macrophages from knockout mice deficient for inflammasome components (NLRP3−/−, Caspase-1/11−/−, Caspase-11−/−), we show that the control of T. gondii infection via P2X7 receptor activation by extracellular ATP (eATP) depends on the canonical inflammasome effector caspase-1, but not on caspase-11 (a non-canonical inflammasome effector). Parasite elimination via P2X7 receptor and inflammasome activation was also dependent on ROS generation and pannexin-1 channel. Treatment with eATP increased IL-1β secretion from infected macrophages, and this effect was dependent on the canonical NLRP3 inflammasome. Finally, treatment with recombinant IL-1β promoted parasite elimination via mitochondrial ROS generation (as assessed using Mito-TEMPO). Together, our results support a model where P2X7 receptor activation by eATP inhibits T. gondii growth in macrophages by triggering NADPH-oxidase-dependent ROS production, and also by activating a canonical NLRP3 inflammasome, which increases IL-1β production (via caspase-1 activity), leading to mitochondrial ROS generation.
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Affiliation(s)
- Aline Cristina Abreu Moreira-Souza
- Immunobiology Program, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Parasitology and Cell Biology Program, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Thuany Prado Rangel
- Immunobiology Program, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil.,Parasitology and Cell Biology Program, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Gabrielle da Costa Rocha
- Immunobiology Program, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maria Bellio
- Department of Immunology, Institute of Microbiology Paulo de Goes, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Dario Simões Zamboni
- Department of Cell Biology, Ribeirão Preto Medical School, University of São Paulo, São Paulo, Brazil
| | - Rossiane Claudia Vommaro
- Parasitology and Cell Biology Program, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Robson Coutinho-Silva
- Immunobiology Program, Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil
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24
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Lin A, Truong B, Patel S, Kaushik N, Choi EH, Fridman G, Fridman A, Miller V. Nanosecond-Pulsed DBD Plasma-Generated Reactive Oxygen Species Trigger Immunogenic Cell Death in A549 Lung Carcinoma Cells through Intracellular Oxidative Stress. Int J Mol Sci 2017; 18:E966. [PMID: 28467380 PMCID: PMC5454879 DOI: 10.3390/ijms18050966] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Revised: 04/27/2017] [Accepted: 04/28/2017] [Indexed: 12/22/2022] Open
Abstract
A novel application for non-thermal plasma is the induction of immunogenic cancer cell death for cancer immunotherapy. Cells undergoing immunogenic death emit danger signals which facilitate anti-tumor immune responses. Although pathways leading to immunogenic cell death are not fully understood; oxidative stress is considered to be part of the underlying mechanism. Here; we studied the interaction between dielectric barrier discharge plasma and cancer cells for oxidative stress-mediated immunogenic cell death. We assessed changes to the intracellular oxidative environment after plasma treatment and correlated it to emission of two danger signals: surface-exposed calreticulin and secreted adenosine triphosphate. Plasma-generated reactive oxygen and charged species were recognized as the major effectors of immunogenic cell death. Chemical attenuators of intracellular reactive oxygen species successfully abrogated oxidative stress following plasma treatment and modulated the emission of surface-exposed calreticulin. Secreted danger signals from cells undergoing immunogenic death enhanced the anti-tumor activity of macrophages. This study demonstrated that plasma triggers immunogenic cell death through oxidative stress pathways and highlights its potential development for cancer immunotherapy.
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Affiliation(s)
- Abraham Lin
- C. & J. Nyheim Plasma Institute, Drexel University, Philadelphia, PA 19104, USA.
| | - Billy Truong
- C. & J. Nyheim Plasma Institute, Drexel University, Philadelphia, PA 19104, USA.
| | - Sohil Patel
- C. & J. Nyheim Plasma Institute, Drexel University, Philadelphia, PA 19104, USA.
| | - Nagendra Kaushik
- Plasma Bioscience Research Center, Kwangwoon University, Seoul 139791, Korea.
| | - Eun Ha Choi
- Plasma Bioscience Research Center, Kwangwoon University, Seoul 139791, Korea.
| | - Gregory Fridman
- C. & J. Nyheim Plasma Institute, Drexel University, Philadelphia, PA 19104, USA.
| | - Alexander Fridman
- C. & J. Nyheim Plasma Institute, Drexel University, Philadelphia, PA 19104, USA.
| | - Vandana Miller
- C. & J. Nyheim Plasma Institute, Drexel University, Philadelphia, PA 19104, USA.
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25
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Anti-tubercular peptides: A quest of future therapeutic weapon to combat tuberculosis. ASIAN PAC J TROP MED 2016; 9:1023-1034. [DOI: 10.1016/j.apjtm.2016.09.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 09/10/2016] [Accepted: 09/20/2016] [Indexed: 11/20/2022] Open
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26
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Purinergic signalling in autoimmunity: A role for the P2X7R in systemic lupus erythematosus? Biomed J 2016; 39:326-338. [PMID: 27884379 PMCID: PMC6138817 DOI: 10.1016/j.bj.2016.08.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 07/29/2016] [Accepted: 08/08/2016] [Indexed: 12/11/2022] Open
Abstract
Purinergic signalling plays a crucial role in immunity and autoimmunity. Among purinergic receptors, the P2X7 receptor (P2X7R) has an undisputed role as it is expressed to high level by immune cells, triggers cytokine release and modulates immune cell differentiation. In this review, we focus on evidence supporting a possible role of the P2X7R in the pathogenesis of systemic lupus erythematosus (SLE).
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Areeshi MY, Mandal RK, Dar S, Wahid M, Khan MEA, Panda AK, Jawed A, Haque S. P2X71513 A>C Polymorphism Confers Increased Risk of Extrapulmonary Tuberculosis: A Meta-analysis of Case-Control Studies. Curr Genomics 2016; 17:450-458. [PMID: 28217002 PMCID: PMC5267471 DOI: 10.2174/1389202917666160513104737] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 03/15/2016] [Accepted: 04/01/2016] [Indexed: 12/16/2022] Open
Abstract
The association of A1513C (rs3751143) polymorphism of P2X7 gene with the risk of extrapulmonary tuberculosis (EPTB) has been extensively analyzed, but no consensus has been achieved. In this study, a meta-analysis was done to assess this precise association. Online web databases, like PubMed (MEDLINE) and EMBASE were searched for pertinent reports showing association of P2X7 A1513C polymorphism with EPTB risk. To assess the strength of this association, we calculated pooled odds ratios (ORs) and 95% confidence intervals (95% CIs). A total of eight reports involving 2237controls and 594 EPTB cases were included in this study. Four genetic models, viz. allele (C vs. A: p=0.011; OR= 1.677, 95% CI = 1.125–2.501), homozygous (CC vs. AA: p = 0.053; OR= 2.362, 95% CI = 0.991–5.632), heterozygous (AC vs. AA: p = 0.003; OR= 1.775, 95% CI = 1.209–2.607) and dominant (CC + AC vs. AA: p = 0.005; OR= 1.890, 95% CI = 1.207–2.962) showed significant associations compared with wild type genotypes. Subgroup analysis stratified by ethnicity was also performed and the results suggested that homozygous and heterozygous genotypes were associated significantly with increased susceptibility of EPTB in Asian population. Similarly, heterozygous and dominant models showed increased EPTB risk in Caucasian population. The present meta-analysis suggests that P2X7 A1513C polymorphism may be an important risk factor for EPTB. Also, our sub-group analysis indicates that P2X7 A1513C polymorphism confers increased EPTB risk among Asians and Caucasians. However, future larger studies are needed to provide more precise conclusion and endorse the present results.
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Affiliation(s)
- Mohammed Y Areeshi
- Research and Scientific Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan-45142, Saudi Arabia
| | - Raju K Mandal
- Research and Scientific Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan-45142, Saudi Arabia
| | - Sajad Dar
- Research and Scientific Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan-45142, Saudi Arabia; The University College of Medical Sciences & GTB Hospital (University of Delhi), Delhi - 110095, India
| | - Mohd Wahid
- Research and Scientific Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan-45142, Saudi Arabia; Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia (A Central University), New Delhi-110025, India
| | - Md Ekhlaque A Khan
- Centre for Life Sciences, Central University of Jharkhand, Brambe, Ranchi-835205, Jharkhand, India
| | - Aditya K Panda
- Centre for Life Sciences, Central University of Jharkhand, Brambe, Ranchi-835205, Jharkhand, India
| | - Arshad Jawed
- Research and Scientific Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan-45142, Saudi Arabia
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing & Allied Health Sciences, Jazan University, Jazan-45142, Saudi Arabia; Department of Biosciences, Faculty of Natural Sciences, Jamia Millia Islamia (A Central University), New Delhi-110025, India
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28
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Almeida-da-Silva CLC, Morandini AC, Ulrich H, Ojcius DM, Coutinho-Silva R. Purinergic signaling during Porphyromonas gingivalis infection. Biomed J 2016; 39:251-260. [PMID: 27793267 PMCID: PMC6140136 DOI: 10.1016/j.bj.2016.08.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 08/02/2016] [Indexed: 01/16/2023] Open
Abstract
Despite recent advances unraveling mechanisms of host-pathogen interactions in innate immunity, the participation of purinergic signaling in infection-driven inflammation remains an emerging research field with many unanswered questions. As one of the most-studied oral pathogens, Porphyromonas gingivalis is considered as a keystone pathogen with a central role in development of periodontal disease. This pathogen needs to evade immune-mediated defense mechanisms and tolerate inflammation in order to survive in the host. In this review, we summarize evidence showing that purinergic signaling modulates P. gingivalis survival and cellular immune responses, and discuss the role played by inflammasome activation and cell death during P. gingivalis infection.
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Affiliation(s)
| | - Ana Carolina Morandini
- Department of Oral Health Sciences, College of Dental Medicine, Medical University of South Carolina, Charleston, SC, USA; Department of Biomedical Sciences, University of the Pacific, San Francisco, USA
| | - Henning Ulrich
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - David M Ojcius
- Immunobiology Program, Biophysics Institute of the Federal University of Rio de Janeiro, Brazil; Department of Biomedical Sciences, University of the Pacific, San Francisco, USA
| | - Robson Coutinho-Silva
- Immunobiology Program, Biophysics Institute of the Federal University of Rio de Janeiro, Brazil.
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29
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Ecto-5'-Nucleotidase (CD73) Deficiency in Mycobacterium tuberculosis-Infected Mice Enhances Neutrophil Recruitment. Infect Immun 2015; 83:3666-74. [PMID: 26150535 DOI: 10.1128/iai.00418-15] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Accepted: 06/28/2015] [Indexed: 12/19/2022] Open
Abstract
The immune system needs safeguards that prevent collateral tissue damage mediated by the immune system while enabling an effective response against a pathogen. The purinergic pathway is one such mechanism and finely modulates inflammation by sensing nucleotides in the environment. Extracellular ATP is considered to be a danger signal leading to a proinflammatory response, whereas adenosine is immunosuppressive. CD73, also called ecto-5'-nucleotidase, occupies a strategic position in this pathway, as it is the main enzyme responsible for the generation of adenosine from ATP. Here, we explore the role of CD73 during tuberculosis, a disease characterized by an immune response that is harmful to the host and unable to eradicate Mycobacterium tuberculosis. Using CD73 knockout (KO) mice, we found that CD73 regulates the response to M. tuberculosis infection in vitro and in vivo. Mycobacterium-infected murine macrophages derived from CD73 KO mice secrete more keratinocyte chemoattractant (KC), tumor necrosis factor alpha (TNF-α), and interleukin-6 (IL-6) and release less vascular endothelial growth factor (VEGF) upon ATP stimulation than do those derived from wild-type (WT) mice. In vivo, CD73 limits the early influx of neutrophils to the lungs without affecting bacterial growth and dissemination. Collectively, our results support the view that CD73 fine-tunes antimycobacterial immune responses.
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Vaeth M, Zee I, Concepcion AR, Maus M, Shaw P, Portal-Celhay C, Zahra A, Kozhaya L, Weidinger C, Philips J, Unutmaz D, Feske S. Ca2+ Signaling but Not Store-Operated Ca2+ Entry Is Required for the Function of Macrophages and Dendritic Cells. THE JOURNAL OF IMMUNOLOGY 2015; 195:1202-17. [PMID: 26109647 DOI: 10.4049/jimmunol.1403013] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 05/26/2015] [Indexed: 01/12/2023]
Abstract
Store-operated Ca(2+) entry (SOCE) through Ca(2+) release-activated Ca(2+) (CRAC) channels is essential for immunity to infection. CRAC channels are formed by ORAI1 proteins in the plasma membrane and activated by stromal interaction molecule (STIM)1 and STIM2 in the endoplasmic reticulum. Mutations in ORAI1 and STIM1 genes that abolish SOCE cause severe immunodeficiency with recurrent infections due to impaired T cell function. SOCE has also been observed in cells of the innate immune system such as macrophages and dendritic cells (DCs) and may provide Ca(2+) signals required for their function. The specific role of SOCE in macrophage and DC function, as well as its contribution to innate immunity, however, is not well defined. We found that nonselective inhibition of Ca(2+) signaling strongly impairs many effector functions of bone marrow-derived macrophages and bone marrow-derived DCs, including phagocytosis, inflammasome activation, and priming of T cells. Surprisingly, however, macrophages and DCs from mice with conditional deletion of Stim1 and Stim2 genes, and therefore complete inhibition of SOCE, showed no major functional defects. Their differentiation, FcR-dependent and -independent phagocytosis, phagolysosome fusion, cytokine production, NLRP3 inflammasome activation, and their ability to present Ags to activate T cells were preserved. Our findings demonstrate that STIM1, STIM2, and SOCE are dispensable for many critical effector functions of macrophages and DCs, which has important implications for CRAC channel inhibition as a therapeutic strategy to suppress pathogenic T cells while not interfering with myeloid cell functions required for innate immunity.
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Affiliation(s)
- Martin Vaeth
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and
| | - Isabelle Zee
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and
| | - Axel R Concepcion
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and
| | - Mate Maus
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and
| | - Patrick Shaw
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and
| | | | - Aleena Zahra
- Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - Lina Kozhaya
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - Carl Weidinger
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and
| | - Jennifer Philips
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and
| | - Derya Unutmaz
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and Department of Medicine, New York University School of Medicine, New York, NY 10016
| | - Stefan Feske
- Department of Pathology, New York University School of Medicine, New York, NY 10016; and
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Bai X, Kinney WH, Su WL, Bai A, Ovrutsky AR, Honda JR, Netea MG, Henao-Tamayo M, Ordway DJ, Dinarello CA, Chan ED. Caspase-3-independent apoptotic pathways contribute to interleukin-32γ-mediated control of Mycobacterium tuberculosis infection in THP-1 cells. BMC Microbiol 2015; 15:39. [PMID: 25887904 PMCID: PMC4349755 DOI: 10.1186/s12866-015-0366-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Accepted: 01/29/2015] [Indexed: 12/12/2022] Open
Abstract
Background Macrophages are the primary effector cells responsible for killing Mycobacterium tuberculosis (MTB) through various mechanisms, including apoptosis. However, MTB can evade host immunity to create a favorable environment for intracellular replication. MTB-infected human macrophages produce interleukin-32 (IL-32). IL-32 is a pro-inflammatory cytokine and has several isoforms. We previously found that IL-32γ reduced the burden of MTB in human macrophages, in part, through the induction of caspase-3-dependent apoptosis. However, based on our previous studies, we hypothesized that caspase-3-independent death pathways may also mediate IL-32 control of MTB infection. Herein, we assessed the potential roles of cathepsin-mediated apoptosis, caspase-1-mediated pyroptosis, and apoptosis-inducing factor (AIF) in mediating IL-32γ control of MTB infection in THP-1 cells. Results Differentiated human THP-1 macrophages were infected with MTB H37Rv alone or in the presence of specific inhibitors to caspase-1, cathepsin B/D, or cathepsin L for up to four days, after which TUNEL-positive cells were quantified; in addition, MTB was quantified by culture as well as by the percentage of THP-1 cells that were infected with green fluorescent protein (GFP)-labeled MTB as determined by microscopy. AIF expression was inhibited using siRNA technology. Inhibition of cathepsin B/D, cathepsin L, or caspase-1 activity significantly abrogated the IL-32γ-mediated reduction in the number of intracellular MTB and of the percentage of GFP-MTB-infected macrophages. Furthermore, inhibition of caspase-1, cathepsin B/D, or cathepsin L in the absence of exogenous IL-32γ resulted in a trend toward an increased proportion of MTB-infected THP-1 cells. Inhibition of AIF activity in the absence of exogenous IL-32γ also increased intracellular burden of MTB. However, since IL-32γ did not induce AIF and because the relative increases in MTB with inhibition of AIF were similar in the presence or absence of IL-32γ, our results indicate that AIF does not mediate the host-protective effect of IL-32γ against MTB. Conclusions The anti-MTB effects of IL-32γ are mediated through classical caspase-3-dependent apoptosis as well as caspase-3-independent apoptosis.
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Affiliation(s)
- Xiyuan Bai
- Department of Medicine, Denver Veterans Affairs Medical Center, Denver, CO, USA. .,Departments of Medicine and Academic Affairs, National Jewish Health, D509, Neustadt Building, 1400 Jackson Street, Denver, CO, 80206, USA. .,Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
| | - William H Kinney
- Department of Medicine, Denver Veterans Affairs Medical Center, Denver, CO, USA. .,Departments of Medicine and Academic Affairs, National Jewish Health, D509, Neustadt Building, 1400 Jackson Street, Denver, CO, 80206, USA. .,Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
| | - Wen-Lin Su
- Division of Pulmonary and Critical Care Medicine, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, New Taipei andTri-Service General Hospital; National Defense Medical Center, Taipei, Taiwan.
| | - An Bai
- Department of Medicine, Denver Veterans Affairs Medical Center, Denver, CO, USA. .,Departments of Medicine and Academic Affairs, National Jewish Health, D509, Neustadt Building, 1400 Jackson Street, Denver, CO, 80206, USA.
| | - Alida R Ovrutsky
- Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
| | - Jennifer R Honda
- Department of Medicine, Denver Veterans Affairs Medical Center, Denver, CO, USA. .,Departments of Medicine and Academic Affairs, National Jewish Health, D509, Neustadt Building, 1400 Jackson Street, Denver, CO, 80206, USA. .,Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
| | - Mihai G Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud University Nijmegen Medical Center, Nijmegen, The Netherlands.
| | - Marcela Henao-Tamayo
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA.
| | - Diane J Ordway
- Mycobacteria Research Laboratories, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA.
| | - Charles A Dinarello
- Division of Infectious Diseases, University of Colorado Denver Anschutz Medical Campus, Aurora, CO, USA.
| | - Edward D Chan
- Department of Medicine, Denver Veterans Affairs Medical Center, Denver, CO, USA. .,Departments of Medicine and Academic Affairs, National Jewish Health, D509, Neustadt Building, 1400 Jackson Street, Denver, CO, 80206, USA. .,Department of Medicine, University of Colorado School of Medicine, Aurora, CO, USA.
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Spencer C, Brown HA. Biochemical characterization of a Pseudomonas aeruginosa phospholipase D. Biochemistry 2015; 54:1208-18. [PMID: 25565226 PMCID: PMC4337821 DOI: 10.1021/bi501291t] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Phospholipase D is a ubiquitous protein in eukaryotes that hydrolyzes phospholipids to generate the signaling lipid phosphatidic acid (PtdOH). PldA, a Pseudomonas aeruginosa PLD, is a secreted protein that targets bacterial and eukaryotic cells. Here we have characterized the in vitro factors that modulate enzymatic activity of PldA, including divalent cations and phosphoinositides. We have identified several similarities between the eukaryotic-like PldA and the human PLD isoforms, as well as several properties in which the enzymes diverge. Notable differences include the substrate preference and transphosphatidylation efficiency for PldA. These findings offer new insights into potential regulatory mechanisms of PldA and its role in pathogenesis.
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Affiliation(s)
- Cierra Spencer
- Department of Pharmacology, and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37232, United States
| | - H. Alex Brown
- Department of Pharmacology, and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37232, United States
- Department of Biochemistry, and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37232, United States
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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.
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Affiliation(s)
- Geoffrey Burnstock
- Autonomic Neuroscience Centre, University College Medical School, Rowland Hill Street, London, NW3 2PF, UK,
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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.
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Affiliation(s)
| | - Robson X Faria
- Laboratory of Cellular Communication, Oswaldo Cruz Foundation, Av, Brazil, 4365 Rio de Janeiro, Brazil.
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35
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MacMicking JD. Cell-autonomous effector mechanisms against mycobacterium tuberculosis. Cold Spring Harb Perspect Med 2014; 4:cshperspect.a018507. [PMID: 25081628 DOI: 10.1101/cshperspect.a018507] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Few pathogens run the gauntlet of sterilizing immunity like Mycobacterium tuberculosis (Mtb). This organism infects mononuclear phagocytes and is also ingested by neutrophils, both of which possess an arsenal of cell-intrinsic effector mechanisms capable of eliminating it. Here Mtb encounters acid, oxidants, nitrosylating agents, and redox congeners, often exuberantly delivered under low oxygen tension. Further pressure is applied by withholding divalent Fe²⁺, Mn²⁺, Cu²⁺, and Zn²⁺, as well as by metabolic privation in the form of carbon needed for anaplerosis and aromatic amino acids for growth. Finally, host E3 ligases ubiquinate, cationic peptides disrupt, and lysosomal enzymes digest Mtb as part of the autophagic response to this particular pathogen. It is a testament to the evolutionary fitness of Mtb that sterilization is rarely complete, although sufficient to ensure most people infected with this airborne bacterium remain disease-free.
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Affiliation(s)
- John D MacMicking
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut 06510
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36
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Caseley EA, Muench SP, Roger S, Mao HJ, Baldwin SA, Jiang LH. Non-synonymous single nucleotide polymorphisms in the P2X receptor genes: association with diseases, impact on receptor functions and potential use as diagnosis biomarkers. Int J Mol Sci 2014; 15:13344-71. [PMID: 25079442 PMCID: PMC4159798 DOI: 10.3390/ijms150813344] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 07/10/2014] [Accepted: 07/14/2014] [Indexed: 12/17/2022] Open
Abstract
P2X receptors are Ca2+-permeable cationic channels in the cell membranes, where they play an important role in mediating a diversity of physiological and pathophysiological functions of extracellular ATP. Mammalian cells express seven P2X receptor genes. Single nucleotide polymorphisms (SNPs) are widespread in the P2RX genes encoding the human P2X receptors, particularly the human P2X7 receptor. This article will provide an overview of the non-synonymous SNPs (NS-SNPs) that have been associated with or implicated in altering the susceptibility to pathologies or disease conditions, and discuss the consequences of the mutations resulting from such NS-SNPs on the receptor functions. Disease-associated NS-SNPs in the P2RX genes have been valuable in understanding the disease etiology and the receptor function, and are promising as biomarkers to be used for the diagnosis and development of stratified therapeutics.
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Affiliation(s)
- Emily A Caseley
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
| | - Stephen P Muench
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
| | | | - Hong-Ju Mao
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Science, Shanghai 200050, China.
| | - Stephen A Baldwin
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
| | - Lin-Hua Jiang
- School of Biomedical Sciences, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, UK.
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Abstract
Treatment of tuberculosis (TB) remains challenging, with lengthy treatment durations and complex drug regimens that are toxic and difficult to administer. Similar to the vast majority of antibiotics, drugs for Mycobacterium tuberculosis are directed against microbial targets. Although more effective drugs that target the bacterium may lead to faster cure of patients, it is possible that a biological limit will be reached that can be overcome only by adopting a fundamentally new treatment approach. TB regimens might be improved by including agents that target host pathways. Recent work on host-pathogen interactions, host immunity, and host-directed interventions suggests that supplementing anti-TB therapy with host modulators may lead to shorter treatment times, a reduction in lung damage caused by the disease, and a lower risk of relapse or reinfection. We undertook this review to identify molecular pathways of the host that may be amenable to modulation by small molecules for the treatment of TB. Although several approaches to augmenting standard TB treatment have been proposed, only a few have been explored in detail or advanced to preclinical and clinical studies. Our review focuses on molecular targets and inhibitory small molecules that function within the macrophage or other myeloid cells, on host inflammatory pathways, or at the level of TB-induced lung pathology.
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A meta-analysis of P2X7 gene-762T/C polymorphism and pulmonary tuberculosis susceptibility. PLoS One 2014; 9:e96359. [PMID: 24810548 PMCID: PMC4014486 DOI: 10.1371/journal.pone.0096359] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 04/05/2014] [Indexed: 12/28/2022] Open
Abstract
AIM We performed a comprehensive meta-analysis to determine the association between P2X7 -762T/C polymorphism and pulmonary tuberculosis susceptibility. METHODOLOGY Based on comprehensive searches of the PubMed, SCI, Elsevier, China National Knowledge Infrastructure (CNKI) and Wanfang Database, we identified eligible studies about the association between P2X7 -762T/C polymorphism and pulmonary tuberculosis risk. Pooled odds ratio (ORs) and 95% confidence intervals (95%CIs) were calculated in random-effects model. RESULTS A total of 2207 tuberculosis cases and 2220 controls in 8 case-control studies were included in this meta-analysis. Allele model (C vs. T: p = 0.15; OR = 0.83, 95% CI = 0.65-1.07), homozygous model (CC vs. TT: p = 0.23; OR = 0.73, 95% CI = 0.44 to 1.22), and heterozygous model (CT vs. TT: p = 0.57; OR = 0.92, 95% CI = 0.68 to 1.24) did not show increased risk of developing pulmonary tuberculosis. Similarly, dominant model (CC+CT vs. TT: p = 0.32; OR = 0.84, 95% CI = 0.59 to 1.19) and recessive model (CC vs. CT+TT: p = 0.08; OR = 0.77, 95% CI = 0.57 to 1.04) failed to show increased risk of developing pulmonary tuberculosis. Subgroup analysis by ethnicity did not detect any significant association between P2X7-762T/C polymorphism and pulmonary tuberculosis susceptibility. CONCLUSIONS P2X7 -762T/C gene polymorphism is not associated with pulmonary tuberculosis susceptibility.
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Dubois-Colas N, Petit-Jentreau L, Barreiro LB, Durand S, Soubigou G, Lecointe C, Klibi J, Rezaï K, Lokiec F, Coppée JY, Gicquel B, Tailleux L. Extracellular adenosine triphosphate affects the response of human macrophages infected with Mycobacterium tuberculosis. J Infect Dis 2014; 210:824-33. [PMID: 24604822 DOI: 10.1093/infdis/jiu135] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Granulomas are the hallmark of Mycobacterium tuberculosis infection. As the host fails to control the bacteria, the center of the granuloma exhibits necrosis resulting from the dying of infected macrophages. The release of the intracellular pool of nucleotides into the surrounding medium may modulate the response of newly infected macrophages, although this has never been investigated. Here, we show that extracellular adenosine triphosphate (ATP) indirectly modulates the expression of 272 genes in human macrophages infected with M. tuberculosis and that it induces their alternative activation. ATP is rapidly hydrolyzed by the ecto-ATPase CD39 into adenosine monophosphate (AMP), and it is AMP that regulates the macrophage response through the adenosine A2A receptor. Our findings reveal a previously unrecognized role for the purinergic pathway in the host response to M. tuberculosis. Dampening inflammation through signaling via the adenosine A2A receptor may limit tissue damage but may also favor bacterial immune escape.
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Affiliation(s)
- Nicolas Dubois-Colas
- Unité de Génétique Mycobactérienne Cellule Pasteur, Université Paris Diderot, Sorbonne Paris Cité, Paris
| | - Laetitia Petit-Jentreau
- Unité de Génétique Mycobactérienne Cellule Pasteur, Université Paris Diderot, Sorbonne Paris Cité, Paris
| | - Luis B Barreiro
- Sainte-Justine Hospital Research Centre, Department of Pediatrics, Faculty of Medicine, University of Montreal, Canada
| | - Sylvère Durand
- Département de Radio-Pharmacologie, Institut Curie-Hôpital René Huguenin, Saint-Cloud, France
| | - Guillaume Soubigou
- Plate-forme Transcriptome et Epigénome, Département Génomes et Génétique, Institut Pasteur
| | | | | | - Keyvan Rezaï
- Département de Radio-Pharmacologie, Institut Curie-Hôpital René Huguenin, Saint-Cloud, France
| | - François Lokiec
- Département de Radio-Pharmacologie, Institut Curie-Hôpital René Huguenin, Saint-Cloud, France
| | - Jean-Yves Coppée
- Plate-forme Transcriptome et Epigénome, Département Génomes et Génétique, Institut Pasteur
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Eugenin EA. Role of connexin/pannexin containing channels in infectious diseases. FEBS Lett 2014; 588:1389-95. [PMID: 24486013 DOI: 10.1016/j.febslet.2014.01.030] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 01/20/2014] [Accepted: 01/21/2014] [Indexed: 12/12/2022]
Abstract
In recent years it has become evident that gap junctions and hemichannels, in concert with extracellular ATP and purinergic receptors, play key roles in several physiological processes and pathological conditions. However, only recently has their importance in infectious diseases been explored, likely because early reports indicated that connexin containing channels were completely inactivated under inflammatory conditions, and therefore no further research was performed. However, recent evidence indicates that several infectious agents take advantage of these communication systems to enhance inflammation and apoptosis, as well as to participate in the infectious cycle of several pathogens. In the current review, we will discuss the role of these channels/receptors in the pathogenesis of several infectious diseases and the possibilities of generating novel therapeutic approaches to reduce or prevent these diseases.
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Affiliation(s)
- Eliseo A Eugenin
- Public Health Research Institute (PHRI), Rutgers New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ, USA; Department of Microbiology and Molecular Genetics, Rutgers New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ, USA.
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Viveiros M, Martins M, Couto I, Rodrigues L, Machado D, Portugal I, Amaral L. Molecular tools for rapid identification and novel effective therapy against MDRTB/XDRTB infections. Expert Rev Anti Infect Ther 2014; 8:465-80. [DOI: 10.1586/eri.10.20] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Implication of purinergic P2X7 receptor in M. tuberculosis infection and host interaction mechanisms: A mouse model study. Immunobiology 2013; 218:1104-12. [DOI: 10.1016/j.imbio.2013.03.003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Revised: 02/06/2013] [Accepted: 03/08/2013] [Indexed: 11/24/2022]
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43
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Boer MC, van Meijgaarden KE, Bastid J, Ottenhoff TH, Joosten SA. CD39 is involved in mediating suppression byMycobacterium bovisBCG-activated human CD8+CD39+regulatory T cells. Eur J Immunol 2013; 43:1925-32. [DOI: 10.1002/eji.201243286] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 03/08/2013] [Accepted: 04/15/2013] [Indexed: 12/19/2022]
Affiliation(s)
- Mardi C. Boer
- Department of Infectious Diseases; Leiden University Medical Center; Leiden; The Netherlands
| | | | | | - Tom H.M. Ottenhoff
- Department of Infectious Diseases; Leiden University Medical Center; Leiden; The Netherlands
| | - Simone A. Joosten
- Department of Infectious Diseases; Leiden University Medical Center; Leiden; The Netherlands
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Bahari G, Hashemi M, Taheri M, Naderi M, Moazeni-Roodi A, Kouhpayeh H, Eskandari-Nasab E. Association of P2X7 gene polymorphisms with susceptibility to pulmonary tuberculosis in Zahedan, Southeast Iran. GENETICS AND MOLECULAR RESEARCH 2013; 12:160-6. [DOI: 10.4238/2013.january.24.8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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45
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Jain R, Dey B, Tyagi AK. Development of the first oligonucleotide microarray for global gene expression profiling in guinea pigs: defining the transcription signature of infectious diseases. BMC Genomics 2012; 13:520. [PMID: 23031549 PMCID: PMC3475082 DOI: 10.1186/1471-2164-13-520] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Accepted: 09/24/2012] [Indexed: 02/04/2023] Open
Abstract
Background The Guinea pig (Cavia porcellus) is one of the most extensively used animal models to study infectious diseases. However, despite its tremendous contribution towards understanding the establishment, progression and control of a number of diseases in general and tuberculosis in particular, the lack of fully annotated guinea pig genome sequence as well as appropriate molecular reagents has severely hampered detailed genetic and immunological analysis in this animal model. Results By employing the cross-species hybridization technique, we have developed an oligonucleotide microarray with 44,000 features assembled from different mammalian species, which to the best of our knowledge is the first attempt to employ microarray to study the global gene expression profile in guinea pigs. To validate and demonstrate the merit of this microarray, we have studied, as an example, the expression profile of guinea pig lungs during the advanced phase of M. tuberculosis infection. A significant upregulation of 1344 genes and a marked down regulation of 1856 genes in the lungs identified a disease signature of pulmonary tuberculosis infection. Conclusion We report the development of first comprehensive microarray for studying the global gene expression profile in guinea pigs and validation of its usefulness with tuberculosis as a case study. An important gap in the area of infectious diseases has been addressed and a valuable molecular tool is provided to optimally harness the potential of guinea pig model to develop better vaccines and therapies against human diseases.
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Affiliation(s)
- Ruchi Jain
- Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
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Reversible inhibition of Chlamydia trachomatis infection in epithelial cells due to stimulation of P2X(4) receptors. Infect Immun 2012; 80:4232-8. [PMID: 22988022 DOI: 10.1128/iai.00441-12] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Bacterial infections of the mucosal epithelium are a major cause of human disease. The prolonged presence of microbial pathogens stimulates inflammation of the local tissues, which leads to changes in the molecular composition of the extracellular milieu. A well-characterized molecule that is released to the extracellular milieu by stressed or infected cells is extracellular ATP and its ecto-enzymatic degradation products, which function as signaling molecules through ligation of purinergic receptors. There has been little information, however, on the effects of the extracellular metabolites on bacterial growth in inflamed tissues. Millimolar concentrations of ATP have been previously shown to inhibit irreversibly bacterial infection through ligation of P2X(7) receptors. We show here that the proinflammatory mediator, ATP, is released from Chlamydia trachomatis-infected epithelial cells. Moreover, further stimulation of the infected cells with micromolar extracellular ADP or ATP significantly impairs the growth of the bacteria, with a profile characteristic of the involvement of P2X(4) receptors. A specific role for P2X(4) was confirmed using cells overexpressing P2X(4). The chlamydiae remain viable and return to normal growth kinetics after removal of the extracellular stimulus, similar to responses previously described for persistence of chlamydial infection.
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Songane M, Kleinnijenhuis J, Netea MG, van Crevel R. The role of autophagy in host defence against Mycobacterium tuberculosis infection. Tuberculosis (Edinb) 2012; 92:388-96. [PMID: 22683183 DOI: 10.1016/j.tube.2012.05.004] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2012] [Revised: 04/11/2012] [Accepted: 05/07/2012] [Indexed: 12/22/2022]
Abstract
Autophagy is a vital homeostatic process triggered by starvation and other cellular stresses, in which cytoplasmatic cargo is targeted for degradation in specialized structures termed autophagosomes. Autophagy is involved in nutrient regeneration, protein and organelle degradation, but also in clearance of intracellular pathogens such as Mycobacterium tuberculosis, the causative agent of tuberculosis. Recent studies suggest that induction of autophagy in macrophages is an effective mechanism to enhance intracellular killing of M. tuberculosis, and that the ability of the pathogen to inhibit this process is of paramount importance for its survival. Patient studies have shown genetic associations between tuberculosis and the autophagy gene IRGM, as well as with several genes indirectly involved in autophagy. In this review we will discuss the complex interplay between M. tuberculosis and autophagy, as well as the effect of polymorphisms in autophagy-related genes on susceptibility to tuberculosis.
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Affiliation(s)
- Mário Songane
- Department of Internal Medicine, Radboud University Nijmegen Medical Centre, and Nijmegen Institute for Infection, Inflammation and Immunity (N4i), Geert Grooteplein Zuid 8, 6525 GA Nijmegen, The Netherlands
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Wiley JS, Sluyter R, Gu BJ, Stokes L, Fuller SJ. The human P2X7 receptor and its role in innate immunity. ACTA ACUST UNITED AC 2012; 78:321-32. [PMID: 21988719 DOI: 10.1111/j.1399-0039.2011.01780.x] [Citation(s) in RCA: 160] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The human P2X7 receptor is a two-transmembrane ionotropic receptor which has a ubiquitous distribution and is most highly expressed on immune cells. In macrophages and similar myeloid cells primed by lipopolysaccharide (LPS), activation of P2X7 by extracellular ATP opens a cation channel/pore allowing massive K+ efflux associated with processing and secretion of pro-inflammatory cytokines interleukin (IL)-1β and IL-18. A variety of other downstream effects follows P2X7 activation over several minutes including shedding of certain surface molecules, membrane blebbing, microvesicle/exosome release and apoptosis of the cell. High concentrations of ATP (>100 µM) are required to activate P2X7 but it remains unclear where these levels exist, other than in inflammatory foci or confined spaces such as in bone. A variety of potent selective antagonists of P2X7 activation have recently become available, allowing clinical trials to be undertaken in inflammatory and immune-mediated disorders. Proteomic studies have shown that P2X7 exists as a large multiprotein complex which includes non-muscle myosin heavy chain and other elements of the cytoskeleton. In the absence of its ATP ligand and serum, P2X7 has an alternate function in the recognition and phagocytosis of non-opsonized foreign particles, including bacteria and apoptotic cells. The P2RX7 gene has many polymorphic variants and isoforms which increase or decrease function of the receptor. Genetic association studies have linked loss-of-function polymorphisms with reactivation of latent tuberculosis as well as symptomatic infection with certain other obligate intracellular pathogens. The many roles involving P2X7 suggest that this receptor is essential to fundamental aspects of the innate immune response.
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Affiliation(s)
- J S Wiley
- Ion Channels and Disease Section, Florey Neuroscience Institutes, University of Melbourne, Parkville, Victoria, Australia.
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Coutinho-Silva R, Ojcius DM. Role of extracellular nucleotides in the immune response against intracellular bacteria and protozoan parasites. Microbes Infect 2012; 14:1271-7. [PMID: 22634346 DOI: 10.1016/j.micinf.2012.05.009] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2012] [Revised: 04/29/2012] [Accepted: 05/14/2012] [Indexed: 02/06/2023]
Abstract
Extracellular nucleotides are danger signals involved in recognition and control of intracellular pathogens. They are an important component of the innate immune response against intracellular pathogens, inducing the recruitment of inflammatory cells, stimulating secretion of cytokines, and producing inflammatory mediators such as reactive oxygen species (ROS) and nitric oxide (NO). In the case of extracellular ATP, some of the immune responses are mediated through activation of the NLRP3 inflammasome and secretion of the cytokine, interleukin-1β (IL-1β), through a mechanism dependent on ligation of the P2X7 receptor. Here we review the role of extracellular nucleotides as sensors of intracellular bacteria and protozoan parasites, and discuss how these pathogens manipulate purinergic signaling to diminish the immune response against infection.
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Affiliation(s)
- Robson Coutinho-Silva
- Biophysics Institute Carlos Chagas Filho, Federal University of Rio de Janeiro, RJ 21941-902, Brazil.
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de Campos NE, Marques-da-Silva C, Corrêa G, Castelo-Branco MTL, de Souza HSP, Coutinho-Silva R. Characterizing the presence and sensitivity of the P2X7 receptor in different compartments of the gut. J Innate Immun 2012; 4:529-41. [PMID: 22508425 DOI: 10.1159/000336628] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2011] [Accepted: 01/18/2012] [Indexed: 01/22/2023] Open
Abstract
Purinergic signaling has been established as an important feature of inflammation and homeostasis. The expression of a number of P2 receptor subtypes in the gut has been reported. In this study, using a well-known permeabilization method that is assessed by flow cytometry, we show that lymphocytes and macrophages from the mesenteric lymph nodes (MLN) and the peritoneal cavity exhibit different sensitivities to extracellular ATP. Compared with the macrophages, the lymphocytes are more sensitive to ATP in the MLN compartment, whereas in the peritoneal cavity the macrophages are more sensitive to ATP than the lymphocytes. In addition, we have shown that the epithelial cells from the small bowel are more resistant to the ATP effects than the cells from the colon. These cells, however, become susceptible after exposure to IFN-γ. Furthermore, by examining parameters such as pH manipulation, the exposure to divalent cations and the P2X7 antagonist Brilliant Blue G, and the use of cells from P2X7(-/-) mice, we have shown that the P2X7 receptors are the ATP-activated receptors responsible for the permeabilization phenomenon. In addition, using Western blot analysis, we have demonstrated the changes in the P2X7 receptor expression in immune cells isolated from different sites in the gut and in the gut-associated lymphoid tissues. Our findings suggest the existence of the site-specific modulation of P2X7 receptors on epithelial and immune cells, and we define purinergic signaling as a new regulatory element in the control of inflammation and cell fate in the gut and in the gut-associated lymphoid tissues.
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Affiliation(s)
- Nathalia Enes de Campos
- Programa de Imunobiologia, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brasil
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