51
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Circulating levels of ATP is a biomarker of HIV cognitive impairment. EBioMedicine 2019; 51:102503. [PMID: 31806564 PMCID: PMC7000317 DOI: 10.1016/j.ebiom.2019.10.029] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 10/14/2019] [Accepted: 10/16/2019] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND In developed countries, Human Immunodeficiency Virus type-1 (HIV-1) infection has become a chronic disease despite the positive effects of anti-retroviral therapies (ART), but still at least half of the HIV infected population shown signs of cognitive impairment. Therefore, biomarkers of HIV cognitive decline are urgently needed. METHODS We analyze the opening of one of the larger channels expressed by humans, pannexin-1 (Panx-1) channels, in the uninfected and HIV infected population (n = 175). We determined channel opening and secretion of intracellular second messengers released through the channel such as PGE2 and ATP. Also, we correlated the opening of Panx-1 channels with the circulating levels of PGE2 and ATP as well as cogntive status of the individuals analyzed. FINDINGS Here, we demonstrate that Panx-1 channels on fresh PBMCs obtained from uninfected individuals are closed and no significant amounts of PGE2 and ATP are detected in the circulation. In contrast, in all HIV-infected individuals analyzed, even the ones under effective ART, a spontaneous opening of Panx-1 channels and increased circulating levels of PGE2 and ATP were detected. Circulating levels of ATP were correlated with cognitive decline in the HIV-infected population supporting that ATP is a biomarker of cognitive disease in the HIV-infected population. INTERPRETATION We propose that circulating levels of ATP could predict CNS compromise and lead to the breakthroughs necessary to detect and prevent brain compromise in the HIV-infected population.
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He P, Zhou W, Liu M, Chen Y. Recent Advances of Small Molecular Regulators Targeting G Protein- Coupled Receptors Family for Oncology Immunotherapy. Curr Top Med Chem 2019; 19:1464-1483. [PMID: 31264549 DOI: 10.2174/1568026619666190628115644] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 12/18/2018] [Accepted: 01/02/2019] [Indexed: 12/21/2022]
Abstract
The great clinical success of chimeric antigen receptor T cell (CAR-T) and PD-1/PDL-1 inhibitor therapies suggests the drawing of a cancer immunotherapy age. However, a considerable proportion of cancer patients currently receive little benefit from these treatment modalities, indicating that multiple immunosuppressive mechanisms exist in the tumor microenvironment. In this review, we mainly discuss recent advances in small molecular regulators targeting G Protein-Coupled Receptors (GPCRs) that are associated with oncology immunomodulation, including chemokine receptors, purinergic receptors, prostaglandin E receptor EP4 and opioid receptors. Moreover, we outline how they affect tumor immunity and neoplasia by regulating immune cell recruitment and modulating tumor stromal cell biology. We also summarize the data from recent clinical advances in small molecular regulators targeting these GPCRs, in combination with immune checkpoints blockers, such as PD-1/PDL-1 and CTLA4 inhibitors, for cancer treatments.
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Affiliation(s)
- Peng He
- Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Wenbo Zhou
- Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Mingyao Liu
- Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
| | - Yihua Chen
- Shanghai Key Laboratory of Regulatory Biology, The Institute of Biomedical Sciences and School of Life Sciences, East China Normal University, Shanghai, 200241, China
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53
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Cross-protective Salmonella vaccine reduces cecal and splenic colonization of multidrug-resistant Salmonella enterica serovar Heidelberg. Vaccine 2019; 37:1255-1259. [DOI: 10.1016/j.vaccine.2018.12.058] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 12/11/2018] [Accepted: 12/16/2018] [Indexed: 01/25/2023]
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54
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Vuerich M, Harshe RP, Robson SC, Longhi MS. Dysregulation of Adenosinergic Signaling in Systemic and Organ-Specific Autoimmunity. Int J Mol Sci 2019; 20:ijms20030528. [PMID: 30691212 PMCID: PMC6386992 DOI: 10.3390/ijms20030528] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/18/2019] [Accepted: 01/22/2019] [Indexed: 12/15/2022] Open
Abstract
Exact causes for autoimmune diseases remain unclear and no cures are available. Breakdown of immunotolerance could set the stage for unfettered immune responses that target self-antigens. Impaired regulatory immune mechanisms could have permissive roles in autoreactivity. Abnormal regulatory immune cell function, therefore, might be a major determinant of the pathogenesis of autoimmune disease. All current treatments are associated with some level of clinical toxicity. Treatment to specifically target dysregulated immunity in these diseases would be a great advance. Extracellular adenosine is a signaling mediator that suppresses inflammation through activation of P1 receptors, most active under pathological conditions. Mounting evidence has linked alterations in the generation of adenosine from extracellular nucleotides by ectonucleotidases, and associated perturbations in purinergic signaling, to the immunological disruption and loss of immunotolerance in autoimmunity. Targeted modulation of the purinergic signaling by either targeting ectonucleotidases or modulating P1 purinergic receptors could therefore restore the balance between autoreactive immune responses; and thereby allow reestablishment of immunotolerance. We review the roles of CD39 and CD73 ectoenzymes in inflammatory states and with the dysregulation of P1 receptor signaling in systemic and organ-specific autoimmunity. Correction of such perturbations could be exploited in potential therapeutic applications.
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Affiliation(s)
- Marta Vuerich
- Department of Anesthesia, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
| | - Rasika P Harshe
- Department of Anesthesia, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
| | - Simon C Robson
- Department of Anesthesia, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
| | - Maria Serena Longhi
- Department of Anesthesia, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, MA 02215, USA.
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55
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Gardner JK, Jackaman C, Mamotte CDS, Nelson DJ. The Regulatory Status Adopted by Lymph Node Dendritic Cells and T Cells During Healthy Aging Is Maintained During Cancer and May Contribute to Reduced Responses to Immunotherapy. Front Med (Lausanne) 2018; 5:337. [PMID: 30560130 PMCID: PMC6287204 DOI: 10.3389/fmed.2018.00337] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 11/15/2018] [Indexed: 12/17/2022] Open
Abstract
Aging is associated with an increased incidence of cancer. One contributing factor could be modulation of immune cells responsible for anti-tumor responses, such as dendritic cells (DCs) and T cells. These immunological changes may also impact the efficacy of cancer immunotherapies in the elderly. The effects of healthy aging on DCs and T cells, and their impact on anti-mesothelioma immune responses, had not been reported. This study examined DCs and T cells in young (2–5 months; equivalent to 16–26 human years) and elderly (20–24 months; equivalent to 60–70 human years) healthy and mesothelioma-bearing C57BL/6J mice. During healthy aging, elderly lymph nodes adopted a regulatory profile, characterized by: (i) increased plasmacytoid DCs, (ii) increased expression of the adenosine-producing enzyme CD73 on CD11c+ cells, and (iii) increased expression of multiple regulatory markers (including CD73, the adenosine A2B receptor, CTLA-4, PD-1, ICOS, LAG-3, and IL-10) on CD8+ and CD4+ T cells, compared to lymph nodes from young mice. Although mesotheliomas grew faster in elderly mice, the increased regulatory status observed in healthy elderly lymph node DCs and T cells was not further exacerbated. However, elderly tumor-bearing mice demonstrated reduced MHC-I, MHC-II and CD80 on CD11c+ cells, and decreased IFN-γ by CD8+ and CD4+ T cells within tumors, compared to young counterparts, implying loss of function. An agonist CD40 antibody based immunotherapy was less efficient at promoting tumor regression in elderly mice, which may be due to: (i) failure of elderly CD8+ T cells to up-regulate perforin, and (ii) increased expression of multiple regulatory markers on CD11c+ cells and T cells in elderly tumor-draining lymph nodes (including CD73, PD-1, ICOS, LAG-3, and TGF-β). Our findings suggest that checkpoint blockade may improve responses to immunotherapy in elderly hosts with mesothelioma, and warrants further investigation.
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Affiliation(s)
- Joanne K Gardner
- School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.,Curtin Health and Innovation Research Institute, Curtin University, Perth, WA, Australia
| | - Connie Jackaman
- School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.,Curtin Health and Innovation Research Institute, Curtin University, Perth, WA, Australia
| | - Cyril D S Mamotte
- School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.,Curtin Health and Innovation Research Institute, Curtin University, Perth, WA, Australia
| | - Delia J Nelson
- School of Pharmacy and Biomedical Sciences, Faculty of Health Sciences, Curtin University, Perth, WA, Australia.,Curtin Health and Innovation Research Institute, Curtin University, Perth, WA, Australia
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56
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Liang D, Shao H, Born WK, O’Brien RL, Kaplan HJ, Sun D. Connection between γδ T-cell- and Adenosine- Mediated Immune Regulation in the Pathogenesis of Experimental Autoimmune Uveitis. Crit Rev Immunol 2018; 38:233-243. [PMID: 30004859 PMCID: PMC6361114 DOI: 10.1615/critrevimmunol.2018026150] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Regulatory effects of γδ T-cells on immune responses have been studied for years. We have investigated the regulatory effect of γδ T-cells on Th1 and Th17 autoimmune responses, and have studied molecular and cellular mechanisms by which γδ T-cells enhance or inhibit immune responses, exploiting a well-characterized murine model of experimental autoimmune uveitis (EAU). Our results show that (1) aberrant γδ T-cell activation is an important pathogenic event in EAU; (2) γδ T-cells have a unique regulatory effect on Th17 autoimmune responses, which is shaped by the activation status of γδ T-cells; and (3) γδ-mediated immunoregulation is closely linked with the extracellular adenosine metabolism. Reciprocal interactions between γδ T-cells and extracellular adenosine partially determine the development of EAU.
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Affiliation(s)
- Dongchun Liang
- Doheny Eye Institute and Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California
| | - Hui Shao
- Department of Ophthalmology and Visual Sciences, Kentucky Lions Eye Center, University of Louisville, Louisville, Kentucky
| | - Willi K. Born
- Department of Biomedical Research, National Jewish Health, Denver, Colorado
| | - Rebecca L. O’Brien
- Department of Biomedical Research, National Jewish Health, Denver, Colorado
| | - Henry J. Kaplan
- Department of Ophthalmology and Visual Sciences, Kentucky Lions Eye Center, University of Louisville, Louisville, Kentucky
| | - Deming Sun
- Doheny Eye Institute and Department of Ophthalmology, David Geffen School of Medicine at UCLA, Los Angeles, California
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57
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Yuan X, Lee JW, Bowser JL, Neudecker V, Sridhar S, Eltzschig HK. Targeting Hypoxia Signaling for Perioperative Organ Injury. Anesth Analg 2018; 126:308-321. [PMID: 28759485 PMCID: PMC5735013 DOI: 10.1213/ane.0000000000002288] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Perioperative organ injury has a significant impact on surgical outcomes and presents a leading cause of death in the United States. Recent research has pointed out an important role of hypoxia signaling in the protection from organ injury, including for example myocardial infarction, acute respiratory distress syndrome, acute kidney, or gut injury. Hypoxia induces the stabilization of hypoxia-inducible factors (HIFs), thereby leading to the induction of HIF target genes, which facilitates adaptive responses to low oxygen. In this review, we focus on current therapeutic strategies targeting hypoxia signaling in various organ injury models and emphasize potential clinical approaches to integrate these findings into the care of surgical patients. Conceptually, there are 2 options to target the HIF pathway for organ protection. First, drugs became recently available that promote the stabilization of HIFs, most prominently via inhibition of prolyl hydroxylase. These compounds are currently trialed in patients, for example, for anemia treatment or prevention of ischemia and reperfusion injury. Second, HIF target genes (such as adenosine receptors) could be activated directly. We hope that some of these approaches may lead to novel pharmacologic strategies to prevent or treat organ injury in surgical patients.
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Affiliation(s)
- Xiaoyi Yuan
- Department of Anesthesiology, the University of Texas Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Jae W. Lee
- Department of Anesthesiology, the University of Texas Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Jessica L. Bowser
- Department of Anesthesiology, the University of Texas Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Viola Neudecker
- Department of Anesthesiology, Clinic of the University of Munich, Munich, Germany
| | - Srikanth Sridhar
- Department of Anesthesiology, the University of Texas Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
| | - Holger K. Eltzschig
- Department of Anesthesiology, the University of Texas Health Science Center at Houston, McGovern Medical School, Houston, TX, USA
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58
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de Andrade Mello P, Coutinho-Silva R, Savio LEB. Multifaceted Effects of Extracellular Adenosine Triphosphate and Adenosine in the Tumor-Host Interaction and Therapeutic Perspectives. Front Immunol 2017; 8:1526. [PMID: 29184552 PMCID: PMC5694450 DOI: 10.3389/fimmu.2017.01526] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2017] [Accepted: 10/27/2017] [Indexed: 12/20/2022] Open
Abstract
Cancer is still one of the world's most pressing health-care challenges, leading to a high number of deaths worldwide. Immunotherapy is a new developing therapy that boosts patient's immune system to fight cancer by modifying tumor-immune cells interaction in the tumor microenvironment (TME). Extracellular adenosine triphosphate (eATP) and adenosine (Ado) are signaling molecules released in the TME that act as modulators of both immune and tumor cell responses. Extracellular adenosine triphosphate and Ado activate purinergic type 2 (P2) and type 1 (P1) receptors, respectively, triggering the so-called purinergic signaling. The concentration of eATP and Ado within the TME is tightly controlled by several cell-surface ectonucleotidases, such as CD39 and CD73, the major ecto-enzymes expressed in cancer cells, immune cells, stromal cells, and vasculature, being CD73 also expressed on tumor-associated fibroblasts. Once accumulated in the TME, eATP boosts antitumor immune response, while Ado attenuates or suppresses immunity against the tumor. In addition, both molecules can mediate growth stimulation or inhibition of the tumor, depending on the specific receptor activated. Therefore, purinergic signaling is able to modulate both tumor and immune cells behavior and, consequently, the tumor-host interaction and disease progression. In this review, we discuss the role of purinergic signaling in the host-tumor interaction detailing the multifaceted effects of eATP and Ado in the inflammatory TME. Moreover, we present recent findings into the application of purinergic-targeting therapy as a potential novel option to boost antitumor immune responses in cancer.
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Affiliation(s)
- Paola de Andrade Mello
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, United States
| | - Robson Coutinho-Silva
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Luiz Eduardo Baggio Savio
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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59
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Allard B, Longhi MS, Robson SC, Stagg J. The ectonucleotidases CD39 and CD73: Novel checkpoint inhibitor targets. Immunol Rev 2017. [PMID: 28258700 DOI: 10.1111/imr.12528]+[] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Cancers are able to grow by subverting immune suppressive pathways, to prevent the malignant cells as being recognized as dangerous or foreign. This mechanism prevents the cancer from being eliminated by the immune system and allows disease to progress from a very early stage to a lethal state. Immunotherapies are newly developing interventions that modify the patient's immune system to fight cancer, by either directly stimulating rejection-type processes or blocking suppressive pathways. Extracellular adenosine generated by the ectonucleotidases CD39 and CD73 is a newly recognized "immune checkpoint mediator" that interferes with anti-tumor immune responses. In this review, we focus on CD39 and CD73 ectoenzymes and encompass aspects of the biochemistry of these molecules as well as detailing the distribution and function on immune cells. Effects of CD39 and CD73 inhibition in preclinical and clinical studies are discussed. Finally, we provide insights into potential clinical application of adenosinergic and other purinergic-targeting therapies and forecast how these might develop in combination with other anti-cancer modalities.
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Affiliation(s)
- Bertrand Allard
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal et Institut du Cancer de Montréal, Montréal, QC, Canada.,Faculté de Pharmacie, Université de Montréal, Montréal, QC, Canada
| | - Maria Serena Longhi
- Divisions of Gastroenterology and Transplantation, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Simon C Robson
- Divisions of Gastroenterology and Transplantation, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - John Stagg
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal et Institut du Cancer de Montréal, Montréal, QC, Canada.,Faculté de Pharmacie, Université de Montréal, Montréal, QC, Canada
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60
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Allard B, Longhi MS, Robson SC, Stagg J. The ectonucleotidases CD39 and CD73: Novel checkpoint inhibitor targets. Immunol Rev 2017. [PMID: 28258700 DOI: 10.1111/imr.12528] [] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cancers are able to grow by subverting immune suppressive pathways, to prevent the malignant cells as being recognized as dangerous or foreign. This mechanism prevents the cancer from being eliminated by the immune system and allows disease to progress from a very early stage to a lethal state. Immunotherapies are newly developing interventions that modify the patient's immune system to fight cancer, by either directly stimulating rejection-type processes or blocking suppressive pathways. Extracellular adenosine generated by the ectonucleotidases CD39 and CD73 is a newly recognized "immune checkpoint mediator" that interferes with anti-tumor immune responses. In this review, we focus on CD39 and CD73 ectoenzymes and encompass aspects of the biochemistry of these molecules as well as detailing the distribution and function on immune cells. Effects of CD39 and CD73 inhibition in preclinical and clinical studies are discussed. Finally, we provide insights into potential clinical application of adenosinergic and other purinergic-targeting therapies and forecast how these might develop in combination with other anti-cancer modalities.
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Affiliation(s)
- Bertrand Allard
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal et Institut du Cancer de Montréal, Montréal, QC, Canada.,Faculté de Pharmacie, Université de Montréal, Montréal, QC, Canada
| | - Maria Serena Longhi
- Divisions of Gastroenterology and Transplantation, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - Simon C Robson
- Divisions of Gastroenterology and Transplantation, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA
| | - John Stagg
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal et Institut du Cancer de Montréal, Montréal, QC, Canada.,Faculté de Pharmacie, Université de Montréal, Montréal, QC, Canada
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61
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Allard B, Longhi MS, Robson SC, Stagg J. The ectonucleotidases CD39 and CD73: Novel checkpoint inhibitor targets. Immunol Rev 2017; 276:121-144. [PMID: 28258700 PMCID: PMC5338647 DOI: 10.1111/imr.12528] [Citation(s) in RCA: 618] [Impact Index Per Article: 88.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cancers are able to grow by subverting immune suppressive pathways, to prevent the malignant cells as being recognized as dangerous or foreign. This mechanism prevents the cancer from being eliminated by the immune system and allows disease to progress from a very early stage to a lethal state. Immunotherapies are newly developing interventions that modify the patient's immune system to fight cancer, by either directly stimulating rejection-type processes or blocking suppressive pathways. Extracellular adenosine generated by the ectonucleotidases CD39 and CD73 is a newly recognized "immune checkpoint mediator" that interferes with anti-tumor immune responses. In this review, we focus on CD39 and CD73 ectoenzymes and encompass aspects of the biochemistry of these molecules as well as detailing the distribution and function on immune cells. Effects of CD39 and CD73 inhibition in preclinical and clinical studies are discussed. Finally, we provide insights into potential clinical application of adenosinergic and other purinergic-targeting therapies and forecast how these might develop in combination with other anti-cancer modalities.
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Affiliation(s)
- Bertrand Allard
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal et Institut du Cancer de Montréal, Montréal, Québec, Canada
- Faculté de Pharmacie, Université de Montréal, Québec, Canada
| | - Maria Serena Longhi
- Divisions of Gastroenterology and Transplantation, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, USA. 02215
| | - Simon C. Robson
- Divisions of Gastroenterology and Transplantation, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, 330 Brookline Avenue, Boston, USA. 02215
| | - John Stagg
- Centre de Recherche du Centre Hospitalier de l’Université de Montréal et Institut du Cancer de Montréal, Montréal, Québec, Canada
- Faculté de Pharmacie, Université de Montréal, Québec, Canada
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62
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Sepúlveda C, Palomo I, Fuentes E. Role of adenosine A2b receptor overexpression in tumor progression. Life Sci 2016; 166:92-99. [DOI: 10.1016/j.lfs.2016.10.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 10/01/2016] [Accepted: 10/07/2016] [Indexed: 02/07/2023]
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63
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Cronstein BN, Sitkovsky M. Adenosine and adenosine receptors in the pathogenesis and treatment of rheumatic diseases. Nat Rev Rheumatol 2016; 13:41-51. [PMID: 27829671 DOI: 10.1038/nrrheum.2016.178] [Citation(s) in RCA: 168] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Adenosine, a nucleoside derived primarily from the extracellular hydrolysis of adenine nucleotides, is a potent regulator of inflammation. Adenosine mediates its effects on inflammatory cells by engaging one or more cell-surface receptors. The expression and function of adenosine receptors on different cell types change during the course of rheumatic diseases, such as rheumatoid arthritis (RA). Targeting adenosine receptors directly for the treatment of rheumatic diseases is currently under study; however, indirect targeting of adenosine receptors by enhancing adenosine levels at inflamed sites accounts for most of the anti-inflammatory effects of methotrexate, the anchor drug for the treatment of RA. In this Review, we discuss the regulation of extracellular adenosine levels and the role of adenosine in regulating the inflammatory and immune responses in rheumatic diseases such as RA, psoriasis and other types of inflammatory arthritis. In addition, adenosine and its receptors are involved in promoting fibrous matrix production in the skin and other organs, and the role of adenosine in fibrosis and fibrosing diseases is also discussed.
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Affiliation(s)
- Bruce N Cronstein
- NYU-HHC Clinical and Translational Science Institute, NYU School of Medicine, 550 First Avenue, New York, New York 10016, USA
| | - Michail Sitkovsky
- New England Inflammation and Tissue Protection Institute, Northeastern University, 360 Huntington Avenue, 312 MU, Boston, Massachusetts 02115, USA
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64
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de Oliveira Bravo M, Carvalho JL, Saldanha-Araujo F. Adenosine production: a common path for mesenchymal stem-cell and regulatory T-cell-mediated immunosuppression. Purinergic Signal 2016; 12:595-609. [PMID: 27557887 DOI: 10.1007/s11302-016-9529-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Accepted: 08/05/2016] [Indexed: 12/14/2022] Open
Abstract
Adenosine is an important molecule that exerts control on the immune system, by signaling through receptors lying on the surface of immune cells. This nucleotide is produced, in part, by the action of the ectoenzymes CD39 and CD73. Interestingly, these proteins are expressed on the cell surface of regulatory T-cells (Tregs) and mesenchymal stromal cells (MSCs)-two cell populations that have emerged as potential therapeutic tools in the field of cell therapy. In fact, the production of adenosine constitutes a mechanism used by both cell types to control the immune response. Recently, great scientific progress was obtained regarding the role of adenosine in the inflammatory environment. In this context, the present review focuses on the advances related to the impact of adenosine production over the immune modulatory activity of Tregs and MSCs, and how this nucleotide controls the biological functions of these cells. Finally, we mention the main challenges and hurdles to bring such molecule to clinical settings.
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Affiliation(s)
| | - Juliana Lott Carvalho
- Genomic Sciences and Biotechnology Center, Catholic University of Brasilia, Brasilia, Brazil
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65
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Allard B, Beavis PA, Darcy PK, Stagg J. Immunosuppressive activities of adenosine in cancer. Curr Opin Pharmacol 2016; 29:7-16. [PMID: 27209048 DOI: 10.1016/j.coph.2016.04.001] [Citation(s) in RCA: 202] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 04/20/2016] [Accepted: 04/29/2016] [Indexed: 12/18/2022]
Abstract
Multiple immunosuppressive mechanisms impede anti-tumor immunity. Among them, the accumulation of extracellular adenosine is a potent and widespread strategy exploited by tumors to escape immunosurveillance through the activation of purinergic receptors. In the immune system, engagement of A2a and A2b adenosine receptors is a critical regulatory mechanism that protects tissues against excessive immune reactions. In tumors, this pathway is hijacked and hinders anti-tumor immunity, promoting cancer progression. Different groups have highlighted the therapeutic potential of blocking CD73-dependent adenosine-mediated immunosuppression to reinstate anti-tumor immunity. Phase clinical trials evaluating anti-CD73 antibodies and A2a receptor antagonists in cancer patients are currently ongoing. We here review the recent literature on the immunosuppressive effects of extracellular adenosine and discuss the development of adenosine inhibitors.
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Affiliation(s)
- Bertrand Allard
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Institut du Cancer de Montréal, 900 Rue Saint-Denis, H2X0A9 Montréal, QC, Canada; Faculté de Pharmacie, Université de Montréal, Pavillon Jean-Coutu, 2940 chemin de Polytechnique, Montréal, QC, Canada
| | - Paul A Beavis
- Cancer Immunology Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville 3010, Australia
| | - Phillip K Darcy
- Cancer Immunology Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Pathology, University of Melbourne, Parkville, Australia
| | - John Stagg
- Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Institut du Cancer de Montréal, 900 Rue Saint-Denis, H2X0A9 Montréal, QC, Canada; Faculté de Pharmacie, Université de Montréal, Pavillon Jean-Coutu, 2940 chemin de Polytechnique, Montréal, QC, Canada.
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Fromonot J, Deharo P, Bruzzese L, Cuisset T, Quilici J, Bonatti S, Fenouillet E, Mottola G, Ruf J, Guieu R. Adenosine plasma level correlates with homocysteine and uric acid concentrations in patients with coronary artery disease. Can J Physiol Pharmacol 2015; 94:272-7. [PMID: 26762617 DOI: 10.1139/cjpp-2015-0193] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The role of hyperhomocysteinemia in coronary artery disease (CAD) patients remains unclear. The present study evaluated the relationship between homocysteine (HCys), adenosine plasma concentration (APC), plasma uric acid, and CAD severity evaluated using the SYNTAX score. We also evaluated in vitro the influence of adenosine on HCys production by hepatoma cultured cells (HuH7). Seventy-eight patients (mean age ± SD: 66.3 ± 11.3; mean SYNTAX score: 19.9 ± 12.3) and 30 healthy subjects (mean age: 61 ± 13) were included. We incubated HuH7 cells with increasing concentrations of adenosine and addressed the effect on HCys level in cell culture supernatant. Patients vs. controls had higher APC (0.82 ± 0.5 μmol/L vs 0.53 ± 0.14 μmol/L; p < 0.01), HCys (15 ± 7.6 μmol/L vs 6.8 ± 3 μmol/L, p < 0.0001), and uric acid (242.6 ± 97 vs 202 ± 59, p < 0.05) levels. APC was correlated with HCys and uric acid concentrations in patients (Pearson's R = 0.65 and 0.52; p < 0.0001, respectively). The SYNTAX score was correlated with HCys concentration. Adenosine induced a time- and dose-dependent increase in HCys in cell culture. Our data suggest that high APC is associated with HCys and uric acid concentrations in CAD patients. Whether the increased APC participates in atherosclerosis or, conversely, is part of a protective regulation process needs further investigations.
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Affiliation(s)
- J Fromonot
- a UMR MD2, Aix Marseille University and IRBA (Institute of Research in Biology of the French Army), School of Medicine, Bvd P Dramard 13015 Marseille, France.,b Laboratory of Biochemistry, Timone University Hospital, Marseille, France
| | - P Deharo
- c Department of Cardiology, Timone University Hospital, Marseille, France
| | - L Bruzzese
- a UMR MD2, Aix Marseille University and IRBA (Institute of Research in Biology of the French Army), School of Medicine, Bvd P Dramard 13015 Marseille, France
| | - T Cuisset
- c Department of Cardiology, Timone University Hospital, Marseille, France
| | - J Quilici
- c Department of Cardiology, Timone University Hospital, Marseille, France
| | - S Bonatti
- d Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II Napoly", Italia
| | - E Fenouillet
- a UMR MD2, Aix Marseille University and IRBA (Institute of Research in Biology of the French Army), School of Medicine, Bvd P Dramard 13015 Marseille, France
| | - G Mottola
- a UMR MD2, Aix Marseille University and IRBA (Institute of Research in Biology of the French Army), School of Medicine, Bvd P Dramard 13015 Marseille, France.,b Laboratory of Biochemistry, Timone University Hospital, Marseille, France
| | - J Ruf
- a UMR MD2, Aix Marseille University and IRBA (Institute of Research in Biology of the French Army), School of Medicine, Bvd P Dramard 13015 Marseille, France
| | - R Guieu
- a UMR MD2, Aix Marseille University and IRBA (Institute of Research in Biology of the French Army), School of Medicine, Bvd P Dramard 13015 Marseille, France.,b Laboratory of Biochemistry, Timone University Hospital, Marseille, France
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Chen M, Liang D, Zuo A, Shao H, Kaplan HJ, Sun D. An A2B Adenosine Receptor Agonist Promotes Th17 Autoimmune Responses in Experimental Autoimmune Uveitis (EAU) via Dendritic Cell Activation. PLoS One 2015; 10:e0132348. [PMID: 26147733 PMCID: PMC4492970 DOI: 10.1371/journal.pone.0132348] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 06/13/2015] [Indexed: 12/13/2022] Open
Abstract
We have recently reported that, although adenosine receptor (AR) agonists have a suppressive effect on Th1 autoreactive T cells, their effect on Th17 autoreactive T cells and γδ T cells is stimulatory and this effect is mainly mediated via A2A adenosine receptors (A2ARs). In this study, we further demonstrate that treatment of C57BL/6 (B6) mice with a selective A2B adenosine receptor (A2BR) agonist greatly enhanced the development of experimental autoimmune uveitis (EAU), whereas treatment with an A2BR antagonist significantly ameliorated severity of EAU. The A2BR agonist-treated mice showed augmented Th17, but not Th1, responses. Mechanistic studies showed that the A2BR agonist-induced enhancement of the Th17 response was significantly lower when TCR-δ-/- mice received the same treatment and that transfer of γδ T cells into TCR-δ-/- mice partially restored this effect. We also showed that dendritic cells (DCs) from A2BR agonist-treated mice showed a significantly increased ability to activate γδ T cells and Th17 autoreactive T cells. Thus, our previous studies have shown that, in EAU, activated γδ T cells possess greatly increased ability to enhance Th17 autoimmune responses. In the present study, we showed that exposure of DCs to A2BR agonist facilitated γδ T cell activation, leading to augmented Th17 responses and progressive EAU development. Our results further support our previous finding that AR agonists have distinct effects on Th1 and Th17 autoimmune responses.
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Affiliation(s)
- Mingjiazi Chen
- Doheny Eye Institute and Department of Ophthalmology, University of California, Los Angeles, CA90033, United States of America
| | - Dongchun Liang
- Doheny Eye Institute and Department of Ophthalmology, University of California, Los Angeles, CA90033, United States of America
| | - Aijun Zuo
- Doheny Eye Institute and Department of Ophthalmology, University of California, Los Angeles, CA90033, United States of America
| | - Hui Shao
- Department of Ophthalmology and Visual Sciences, Kentucky Lions Eye Center, University of Louisville, Louisville, KY40202, United States of America
| | - Henry J. Kaplan
- Department of Ophthalmology and Visual Sciences, Kentucky Lions Eye Center, University of Louisville, Louisville, KY40202, United States of America
| | - Deming Sun
- Doheny Eye Institute and Department of Ophthalmology, University of California, Los Angeles, CA90033, United States of America
- * E-mail:
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Crean D, Cummins EP, Bahar B, Mohan H, McMorrow JP, Murphy EP. Adenosine Modulates NR4A Orphan Nuclear Receptors To Attenuate Hyperinflammatory Responses in Monocytic Cells. THE JOURNAL OF IMMUNOLOGY 2015; 195:1436-48. [PMID: 26150530 DOI: 10.4049/jimmunol.1402039] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 06/02/2015] [Indexed: 02/02/2023]
Abstract
Adenosine receptor-mediated regulation of monocyte/macrophage inflammatory responses is critical in the maintenance of tissue homeostasis. In this study, we reveal that adenosine potently modulates the expression of NR4A1, 2, and 3 orphan nuclear receptors in myeloid cells, and this modulation is primarily through the adenosine A2a receptor subtype. We demonstrate that A2a receptor activation of NR4A1-3 receptor synthesis is further enhanced in TLR4-stimulated monocytes. After TLR4 stimulation, NR4A receptor-depleted monocyte/macrophage cells display significantly altered expression of cell-surface markers and produce increased inflammatory cytokine and chemokine secretion rendering the cells an enhanced proinflammatory phenotype. Exposure of TLR4 or TNF-α-stimulated monocytes to adenosine analogs directs changes in the expression of MIP-3α and IL-23p19, with NR4A2 depletion leading to significantly enhanced expression of these factors. Furthermore, we establish that nuclear levels of NF-κB/p65 are increased in TLR/adenosine-stimulated NR4A2-depleted cells. We show that, after TLR/adenosine receptor stimulation, NR4A2 depletion promotes significant binding of NF-κB/p65 to a κB consensus binding motif within the MIP-3α proximal promoter leading to increased protein secretion, confirming a pivotal role for NF-κB activity in controlling cellular responses and gene expression outcomes in response to these mediators. Thus, these data demonstrate that during an inflammatory response, adenosine modulation of NR4A receptor activity acts to limit NF-κB-mediated effects and that loss of NR4A2 expression leads to enhanced NF-κB activity and hyperinflammatory responses in myeloid cells.
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Affiliation(s)
- Daniel Crean
- UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland; and Conway Institute for Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - Eoin P Cummins
- Conway Institute for Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
| | - Bojlul Bahar
- UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland; and
| | - Helen Mohan
- UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland; and
| | - Jason P McMorrow
- UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland; and
| | - Evelyn P Murphy
- UCD Veterinary Sciences Centre, University College Dublin, Belfield, Dublin 4, Ireland; and Conway Institute for Biomolecular and Biomedical Research, University College Dublin, Belfield, Dublin 4, Ireland
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Vincent IS, Okusa MD. Adenosine 2A receptors in acute kidney injury. Acta Physiol (Oxf) 2015; 214:303-10. [PMID: 25877257 DOI: 10.1111/apha.12508] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2014] [Revised: 10/14/2014] [Accepted: 04/12/2015] [Indexed: 12/23/2022]
Abstract
Acute kidney injury (AKI) is an important clinical problem that may lead to death and for those who survive, the sequelae of AKI include loss of quality of life, chronic kidney disease and end-stage renal disease. The incidence of AKI continues to rise without clear successes in humans for the pharmacological prevention of AKI or treatment of established AKI. Dendritic cells and macrophages are critical early initiators of innate immunity in the kidney and orchestrate inflammation subsequent to ischaemia-reperfusion injury. These innate cells are the most abundant leucocytes present in the kidney, and they represent a heterogeneous population of cells that are capable of responding to cues from the microenvironment derived from pathogens or endogenous inflammatory mediators such as cytokines or anti-inflammatory mediators such as adenosine. Lymphocyte subsets such as natural killer T cells and Tregs also play roles in regulating ischaemic injury by promoting and suppressing inflammation respectively. Adenosine, produced in response to IR, is generally considered as a protective signalling molecule and elicits its physiological responses through four distinct adenosine receptors. However, its short half-life, lack of specificity and rapid metabolism limit the use of adenosine as a therapeutic agent. These adenosine receptors play various roles in regulating the activity of the aforementioned hematopoietic cells in elevated levels of adenosine such as during hypoxia. This review focuses on the importance of one receptor, the adenosine 2A subtype, in blocking inflammation associated with AKI.
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Affiliation(s)
- I. S. Vincent
- Division of Nephrology and Center for Immunity; Inflammation and Regenerative Medicine; University of Virginia Health System; Charlottesville VA USA
| | - M. D. Okusa
- Division of Nephrology and Center for Immunity; Inflammation and Regenerative Medicine; University of Virginia Health System; Charlottesville VA USA
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Weinhage T, Däbritz J, Brockhausen A, Wirth T, Brückner M, Belz M, Foell D, Varga G. Granulocyte Macrophage Colony-Stimulating Factor-Activated CD39 +/CD73 + Murine Monocytes Modulate Intestinal Inflammation via Induction of Regulatory T Cells. Cell Mol Gastroenterol Hepatol 2015; 1:433-449.e1. [PMID: 28210690 PMCID: PMC5301274 DOI: 10.1016/j.jcmgh.2015.04.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 04/28/2015] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Granulocyte macrophage colony-stimulating factor (GM-CSF) treatment induces clinical response in patients with active Crohn's disease. To explore whether monocytes mediate GM-CSF effects in vivo, we used a mouse model of chronic colitis induced by dextran sulfate sodium (DSS). METHODS Murine bone marrow-derived monocytes were activated with GM-CSF in vitro, and gene expression, phenotype, and function of GM-CSF-activated monocytes (GMaM) were analyzed. Therapeutic effects of GMaM were assessed in a model of chronic colitis induced by repeated cycles of DSS. Monocytes were administered intravenously and their immunomodulatory functions were evaluated in vivo by clinical monitoring, histology, endoscopy, immunohistochemistry, and expression of inflammatory markers in the colon. The distribution of injected monocytes in the intestine was measured by in vivo imaging. RESULTS GMaM expressed significantly higher levels of anti-inflammatory molecules. Production of reactive oxygen species was also increased while phagocytosis and adherence were decreased. GMaM up-regulated CD39 and CD73, which allows the conversion of adenosine triphosphate into adenosine and coincided with the induction of Foxp3+ (forkhead-box-protein P3 positive) regulatory T cells (Treg) in cocultures of GMaM and naive T cells. In chronic DSS-induced colitis, adoptive transfer of GMaM led to significant clinical improvement, as demonstrated by reduced weight loss, inflammatory infiltration, ulceration, and colon shrinkage. As GMaM migrated faster and persisted longer in the inflamed intestine compared with control monocytes, their presence induced Treg generation in vivo. CONCLUSIONS GM-CSF leads to specific monocyte activation that modulates experimental colitis via mechanisms that include the induction of Treg. We demonstrate a possible mechanism of Treg induction through CD39 and CD73 expression on monocytes.
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Key Words
- ALDH, aldehyde dehydrogenase
- ATP, adenosine triphosphate
- Adaptive Immunity
- Arg1, arginase 1
- CD, Crohn’s disease
- CD39, E-NTPDase
- CD73, ecto-5′-nucleotidase
- CFSE, carboxyfluorescein succinimidyl ester
- DC, dendritic cells
- DSS, dextran sulfate sodium
- Dextran Sulfate Sodium
- Experimental Colitis
- FCS, fetal calf serum
- Foxp3, forkhead-box-protein P3
- GM-CSF
- GM-CSF, granulocyte macrophage colony-stimulating factor
- GMaM, granulocyte-macrophage colony-stimulating factor–activated monocytes
- IBD, inflammatory bowel disease
- IL, interleukin
- IL-1Ra, IL-1 receptor antagonist
- Immune Response
- Innate Immunity
- LPS, lipopolysaccharide
- MACS, magnetic-activated cell sorting
- MEICS, murine endoscopic index of colitis severity
- Monocyte
- NO, nitric oxide
- OD, optical density
- PBS, phosphate-buffered saline
- PCR, polymerase chain reaction
- RA, retinoic acid
- ROS, reactive oxygen species
- T Cell
- TNFα, tumor necrosis factor α
- Treg, regulatory T cells
- WT, wild type
- qRT-PCR, quantitative reverse-transcription polymerase chain reaction
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Affiliation(s)
- Toni Weinhage
- Department of Pediatric Rheumatology and Immunology, University Children’s Hospital Münster, Münster, Germany
- Correspondence Address correspondence to: Toni Weinhage, MSc, University Children’s Hospital Münster, Department of Pediatric Rheumatology and Immunology, Domagkstraße 3, D-48149 Münster, Germany. fax: +49 (0)251 8358104.
| | - Jan Däbritz
- Department of Pediatric Rheumatology and Immunology, University Children’s Hospital Münster, Münster, Germany
- The Royal Children’s Hospital Melbourne, Murdoch Children’s Research Institute, Gastrointestinal Research in Inflammation and Pathology, Parkville, Australia
- Interdisciplinary Centre of Clinical Research, University of Münster, Münster, Germany
- Department of Pediatrics, University of Melbourne, Melbourne Medical School, Parkville, Australia
| | - Anne Brockhausen
- Department of Translational Dermatoinfectiology, University of Münster, Münster, Germany
| | - Timo Wirth
- Department of Pediatric Rheumatology and Immunology, University Children’s Hospital Münster, Münster, Germany
| | - Markus Brückner
- Department of Pediatric Rheumatology and Immunology, University Children’s Hospital Münster, Münster, Germany
- Department of Medicine B, University Hospital Münster, Münster, Germany
| | - Michael Belz
- Department of Pediatric Rheumatology and Immunology, University Children’s Hospital Münster, Münster, Germany
- Department of Dermatology, University Hospital Münster, Münster, Germany
| | - Dirk Foell
- Department of Pediatric Rheumatology and Immunology, University Children’s Hospital Münster, Münster, Germany
- Interdisciplinary Centre of Clinical Research, University of Münster, Münster, Germany
| | - Georg Varga
- Department of Pediatric Rheumatology and Immunology, University Children’s Hospital Münster, Münster, Germany
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Gammaherpesvirus small noncoding RNAs are bifunctional elements that regulate infection and contribute to virulence in vivo. mBio 2015; 6:e01670-14. [PMID: 25691585 PMCID: PMC4337559 DOI: 10.1128/mbio.01670-14] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Many viruses express noncoding RNAs (ncRNAs). The gammaherpesviruses (γHVs), including Epstein-Barr virus, Kaposi’s sarcoma-associated herpesvirus, and murine γHV68, each contain multiple ncRNA genes, including microRNAs (miRNAs). While these ncRNAs can regulate multiple host and viral processes in vitro, the genetic contribution of these RNAs to infection and pathogenesis remains largely unknown. To study the functional contribution of these RNAs to γHV infection, we have used γHV68, a small-animal model of γHV pathogenesis. γHV68 encodes eight small hybrid ncRNAs that contain both tRNA-like elements and functional miRNAs. These genes are transcribed by RNA polymerase III and are referred to as the γHV68 TMERs (tRNA-miRNA-encoded RNAs). To determine the total concerted genetic contribution of these ncRNAs to γHV acute infection and pathogenesis, we generated and characterized a recombinant γHV68 strain devoid of all eight TMERs. TMER-deficient γHV68 has wild-type levels of lytic replication in vitro and normal establishment of latency in B cells early following acute infection in vivo. In contrast, during acute infection of immunodeficient mice, TMER-deficient γHV68 has reduced virulence in a model of viral pneumonia, despite having an enhanced frequency of virus-infected cells. Strikingly, expression of a single viral tRNA-like molecule, in the absence of all other virus-encoded TMERs and miRNAs, reverses both attenuation in virulence and enhanced frequency of infected cells. These data show that γHV ncRNAs play critical roles in acute infection and virulence in immunocompromised hosts and identify these RNAs as a new potential target to modulate γHV-induced infection and pathogenesis. The gammaherpesviruses (γHVs) are a subfamily of viruses associated with chronic inflammatory diseases and cancer, particularly in immunocompromised individuals. These viruses uniformly encode multiple types of noncoding RNAs (ncRNAs) that are not translated into proteins. It remains unclear how virus-expressed ncRNAs influence the course and outcome of infection in vivo. Here, we generated a mouse γHV that lacks the expression of multiple ncRNAs. Notably, this mutant virus is critically impaired in the ability to cause disease in immunocompromised hosts yet shows a paradoxical increase in infected cells early during infection in these hosts. While the original mouse virus encodes multiple ncRNAs, the expression of a single domain of one ncRNA can partially reverse the defects of the mutant virus. These studies demonstrate that γHV ncRNAs can directly contribute to virus-induced disease in vivo and that these RNAs may be multifunctional, allowing the opportunity to specifically interfere with different functional domains of these RNAs.
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Neildez-Nguyen TMA, Bigot J, Da Rocha S, Corre G, Boisgerault F, Paldi A, Galy A. Hypoxic culture conditions enhance the generation of regulatory T cells. Immunology 2015; 144:431-443. [PMID: 25243909 DOI: 10.1111/imm.12388] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 09/11/2014] [Accepted: 09/16/2014] [Indexed: 12/12/2022] Open
Abstract
The generation of large amounts of induced CD4+ CD25+ Foxp3+ regulatory T (iTreg) cells is of great interest for several immunotherapy applications, therefore a better understanding of signals controlling iTreg cell differentiation and expansion is required. There is evidence that oxidative metabolism may regulate several key signalling pathways in T cells. This prompted us to investigate the effects of oxygenation on iTreg cell generation by comparing the effects of atmospheric (21%) or of low (5%) O2 concentrations on the phenotype of bead-stimulated murine splenic CD4+ T cells from Foxp3-KI-GFP T-cell receptor transgenic mice. The production of intracellular reactive oxygen species was shown to play a major role in the generation of iTreg cells, a process characterized by increased levels of Sirt1, PTEN and Glut1 on the committed cells, independently of the level of oxygenation. The suppressive function of iTreg cells generated either in atmospheric or low oxygen levels was equivalent. However, greater yields of iTreg cells were obtained under low oxygenation, resulting from a higher proliferative rate of the committed Treg cells and higher levels of Foxp3, suggesting a better stability of the differentiation process. Higher expression of Glut1 detected on iTreg cells generated under hypoxic culture conditions provides a likely explanation for the enhanced proliferation of these cells as compared to those cultured under ambient oxygen. Such results have important implications for understanding Treg cell homeostasis and developing in vitro protocols for the generation of Treg cells from naive T lymphocytes.
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Affiliation(s)
- Thi My Anh Neildez-Nguyen
- Inserm, U951, Genethon, Evry, France.,Ecole Pratique des Hautes Etudes, University of Evry Val d'Essonne UMR_S951, Genethon, Evry, France.,Molecular Immunology and Innovative Biotherapies group, Genethon, Evry, F91002, France
| | - Jérémy Bigot
- Inserm, U951, Genethon, Evry, France.,Ecole Pratique des Hautes Etudes, University of Evry Val d'Essonne UMR_S951, Genethon, Evry, France.,Molecular Immunology and Innovative Biotherapies group, Genethon, Evry, F91002, France
| | - Sylvie Da Rocha
- Inserm, U951, Genethon, Evry, France.,Ecole Pratique des Hautes Etudes, University of Evry Val d'Essonne UMR_S951, Genethon, Evry, France.,Molecular Immunology and Innovative Biotherapies group, Genethon, Evry, F91002, France
| | - Guillaume Corre
- Inserm, U951, Genethon, Evry, France.,Ecole Pratique des Hautes Etudes, University of Evry Val d'Essonne UMR_S951, Genethon, Evry, France.,Molecular Immunology and Innovative Biotherapies group, Genethon, Evry, F91002, France
| | - Florence Boisgerault
- Inserm, U951, Genethon, Evry, France.,Ecole Pratique des Hautes Etudes, University of Evry Val d'Essonne UMR_S951, Genethon, Evry, France.,Molecular Immunology and Innovative Biotherapies group, Genethon, Evry, F91002, France
| | - Andràs Paldi
- Inserm, U951, Genethon, Evry, France.,Ecole Pratique des Hautes Etudes, University of Evry Val d'Essonne UMR_S951, Genethon, Evry, France.,Molecular Immunology and Innovative Biotherapies group, Genethon, Evry, F91002, France
| | - Anne Galy
- Inserm, U951, Genethon, Evry, France.,Ecole Pratique des Hautes Etudes, University of Evry Val d'Essonne UMR_S951, Genethon, Evry, France.,Molecular Immunology and Innovative Biotherapies group, Genethon, Evry, F91002, France
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Kohno K, Ohashi E, Sano O, Kusano H, Kunikata T, Arai N, Hanaya T, Kawata T, Nishimoto T, Fukuda S. Anti-inflammatory effects of adenosine N1-oxide. J Inflamm (Lond) 2015; 12:2. [PMID: 25632271 PMCID: PMC4308844 DOI: 10.1186/s12950-014-0045-0] [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: 03/19/2014] [Accepted: 12/16/2014] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Adenosine is a potent endogenous anti-inflammatory and immunoregulatory molecule. Despite its promise, adenosine's extremely short half-life in blood limits its clinical application. Here, we examined adenosine N1-oxide (ANO), which is found in royal jelly. ANO is an oxidized product of adenosine at the N1 position of the adenine base moiety. We found that it is refractory to adenosine deaminase-mediated conversion to inosine. We further examined the anti-inflammatory activities of ANO in vitro and in vivo. METHODS The effect of ANO on pro-inflammatory cytokine secretion was examined in mouse peritoneal macrophages and the human monocytic cell line THP-1, and compared with that of adenosine, synthetic adenosine receptor (AR)-selective agonists and dipotassium glycyrrhizate (GK2). The anti-inflammatory activity of ANO in vivo was examined in an LPS-induced endotoxin shock model in mice. RESULTS ANO inhibited secretion of inflammatory mediators at much lower concentrations than adenosine and GK2 when used with peritoneal macrophages and THP-1 cells that were stimulated by LPS plus IFN-γ. The potent anti-inflammatory activity of ANO could not be solely accounted for by its refractoriness to adenosine deaminase. ANO was superior to the synthetic A1 AR-selective agonist, 2-chloro-N(6)-cyclopentyladenosine (CCPA), A2A AR-selective agonist, 2-[p-(2-carboxyethyl)phenethylamino]-5'-N-ethylcarboxamideadenosine hydrochloride (CGS21680), and A3 AR-selective agonist, N(6)-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA), in suppressing the secretion of a broad spectrum of pro-inflammatory cytokines by peritoneal macrophages. The capacities of ANO to inhibit pro-inflammatory cytokine production by THP-1 cells were comparable with those of CCPA and IB-MECA. Reflecting its potent anti-inflammatory effects in vitro, intravenous administration of ANO significantly reduced lethality of LPS-induced endotoxin shock. A significant increase in survival rate was also observed by oral administration of ANO. Mechanistic analysis suggested that the up-regulation of the anti-inflammatory transcription factor c-Fos was, at least in part, involved in the ANO-induced suppression of pro-inflammatory cytokine secretion. CONCLUSIONS Our data suggest that ANO, a naturally occurring molecule that is structurally close to adenosine but is functionally more potent, presents potential strategies for the treatment of inflammatory disorders.
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Affiliation(s)
- Keizo Kohno
- />Core Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
| | - Emiko Ohashi
- />Core Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
| | - Osamu Sano
- />Core Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
| | - Hajime Kusano
- />Functional Dye Division, Functional Dye Department, Hayashibara Co., Ltd, Okayama, Japan
| | - Toshio Kunikata
- />Core Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
| | - Norie Arai
- />Applied Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
| | - Toshiharu Hanaya
- />Core Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
| | - Toshio Kawata
- />Functional Dye Division, Functional Dye Department, Hayashibara Co., Ltd, Okayama, Japan
| | - Tomoyuki Nishimoto
- />Core Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
| | - Shigeharu Fukuda
- />Core Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
- />Applied Technology Division, Research and Development Center, Hayashibara Co., Ltd, Okayama, Japan
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74
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Eltzschig HK, Bratton DL, Colgan SP. Targeting hypoxia signalling for the treatment of ischaemic and inflammatory diseases. Nat Rev Drug Discov 2014; 13:852-69. [PMID: 25359381 PMCID: PMC4259899 DOI: 10.1038/nrd4422] [Citation(s) in RCA: 276] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Hypoxia-inducible factors (HIFs) are stabilized during adverse inflammatory processes associated with disorders such as inflammatory bowel disease, pathogen infection and acute lung injury, as well as during ischaemia-reperfusion injury. HIF stabilization and hypoxia-induced changes in gene expression have a profound impact on the inflamed tissue microenvironment and on disease outcomes. Although the mechanism that initiates HIF stabilization may vary, the final molecular steps that control HIF stabilization converge on a set of oxygen-sensing prolyl hydroxylases (PHDs) that mark HIFs for proteasomal degradation. PHDs are therefore promising therapeutic targets. In this Review, we discuss the emerging potential and associated challenges of targeting the PHD-HIF pathway for the treatment of inflammatory and ischaemic diseases.
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Affiliation(s)
- Holger K Eltzschig
- Organ Protection Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, Colorado 80045, USA
| | - Donna L Bratton
- Department of Pediatrics, National Jewish Health, Denver, Colorado 80206, USA
| | - Sean P Colgan
- Mucosal Inflammation Program, Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado 80045, USA
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Kaji W, Tanaka S, Tsukimoto M, Kojima S. Adenosine A(2B) receptor antagonist PSB603 suppresses tumor growth and metastasis by inhibiting induction of regulatory T cells. J Toxicol Sci 2014; 39:191-8. [PMID: 24646699 DOI: 10.2131/jts.39.191] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Regulatory T cells (Treg) play a role in suppression of immune response, including anti-tumor immunity. We have recently reported that treatment of naïve CD4 T cells with adenosine A(2B) receptor antagonist PSB603 under Treg-skewing conditions inhibits expression of Foxp3, a marker of differentiation to Treg, without blocking IL-2 production or CD25 expression, which are activation markers, in CD4 T cells. We hypothesized that PSB603 suppresses cancer growth and metastasis by inhibiting induction of Treg, thereby facilitating anti-tumor immunity. In this study, we first examined the effect of PSB603 on tumor growth in B16 melanoma-bearing C57BL/6 mice. Administration of PSB603 significantly suppressed the increase of tumor volume as well as the increase of Treg population in these mice. The populations of CD4 and CD8 T cells were higher and splenic lymphocyte-mediated cytotoxicity towards B16 melanoma was significantly increased in PSB603-treated mice. We confirmed that PSB603 did not reduce the viability of B16 melanoma cells in vitro. Moreover, we also examined the effect of PSB603 on tumor metastasis in pulmonary metastasis model mice intravenously injected with B16 melanoma cells. The metastasis was also suppressed in PSB603-treated mice, in which the population of Treg was significantly lower. Overall, our results suggest that A(2B) receptor antagonist PSB603 enhances anti-tumor immunity by inhibiting differentiation to Treg, resulting in a delay of tumor growth and a suppression of metastasis.
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Affiliation(s)
- Wakako Kaji
- Faculty of Pharmaceutical Sciences, Tokyo University of Science
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Liang D, Zuo A, Shao H, Chen M, Kaplan HJ, Sun D. Roles of the adenosine receptor and CD73 in the regulatory effect of γδ T cells. PLoS One 2014; 9:e108932. [PMID: 25268760 PMCID: PMC4182534 DOI: 10.1371/journal.pone.0108932] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/04/2014] [Indexed: 11/18/2022] Open
Abstract
The adenosine A2A receptor (A2AR), the main functional adenosine receptor on murine T cells, plays a unique role in the attenuation of inflammation and tissue damage in vivo. Here, we showed that, of the immune cell types tested, activated γδ T cells expressed the highest levels of A2AR mRNA and that A2AR ligation inhibited αβ T cell activation, but enhanced γδ T cell activation. We also showed that the inhibitory effect of an adenosine receptor agonist on autoreactive T cells was prevented by addition of a low percentage of activated γδ T cells. Furthermore, compared to resting cells, activated γδ T cells expressed significantly lower levels of CD73, an enzyme involved in the generation of extracellular adenosine. Exogenous AMP had a significant inhibitory effect on autoreactive T cell responses, but only in the presence of CD73+ γδ T cells, and this effect was abolished by a CD73 inhibitor. Our results show that expression of increased amounts of A2AR allows γδ T cells to bind adenosine and thereby attenuate its suppressive effect, while decreased expression of CD73 results in less generation of adenosine in the inflammatory site. Together, these events allow activated γδ T cells to acquire increased proinflammatory activity, leading to augmented autoimmune responses.
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Affiliation(s)
- Dongchun Liang
- Doheny Eye Institute, Department of Ophthalmology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Aijun Zuo
- Doheny Eye Institute, Department of Ophthalmology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Hui Shao
- Department of Ophthalmology and Visual Sciences, Kentucky Lions Eye Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Mingjiazi Chen
- Doheny Eye Institute, Department of Ophthalmology, University of California Los Angeles, Los Angeles, California, United States of America
| | - Henry J. Kaplan
- Department of Ophthalmology and Visual Sciences, Kentucky Lions Eye Center, University of Louisville, Louisville, Kentucky, United States of America
| | - Deming Sun
- Doheny Eye Institute, Department of Ophthalmology, University of California Los Angeles, Los Angeles, California, United States of America
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77
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Idzko M, Ferrari D, Riegel AK, Eltzschig HK. Extracellular nucleotide and nucleoside signaling in vascular and blood disease. Blood 2014; 124:1029-37. [PMID: 25001468 PMCID: PMC4133480 DOI: 10.1182/blood-2013-09-402560] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Accepted: 06/16/2014] [Indexed: 12/17/2022] Open
Abstract
Nucleotides and nucleosides-such as adenosine triphosphate (ATP) and adenosine-are famous for their intracellular roles as building blocks for the genetic code or cellular energy currencies. In contrast, their function in the extracellular space is different. Here, they are primarily known as signaling molecules via activation of purinergic receptors, classified as P1 receptors for adenosine or P2 receptors for ATP. Because extracellular ATP is rapidly converted to adenosine by ectonucleotidase, nucleotide-phosphohydrolysis is important for controlling the balance between P2 and P1 signaling. Gene-targeted mice for P1, P2 receptors, or ectonucleotidase exhibit only very mild phenotypic manifestations at baseline. However, they demonstrate alterations in disease susceptibilities when exposed to a variety of vascular or blood diseases. Examples of phenotypic manifestations include vascular barrier dysfunction, graft-vs-host disease, platelet activation, ischemia, and reperfusion injury or sickle cell disease. Many of these studies highlight that purinergic signaling events can be targeted therapeutically.
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Affiliation(s)
- Marco Idzko
- Department of Pneumology, Freiburg University Medical Center, Albert-Ludwigs-University, Freiburg, Germany
| | - Davide Ferrari
- Department of Morphology, Surgery and Experimental Medicine, Section of General Pathology, Oncology and Experimental Biology, University of Ferrara, Ferrara, Italy; and
| | - Ann-Kathrin Riegel
- Organ Protection Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, CO
| | - Holger K Eltzschig
- Organ Protection Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, CO
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Ohta A, Sitkovsky M. Extracellular adenosine-mediated modulation of regulatory T cells. Front Immunol 2014; 5:304. [PMID: 25071765 PMCID: PMC4091046 DOI: 10.3389/fimmu.2014.00304] [Citation(s) in RCA: 224] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2014] [Accepted: 06/15/2014] [Indexed: 12/20/2022] Open
Abstract
Extracellular adenosine-dependent suppression and redirection of pro-inflammatory activities are mediated by the signaling through adenosine receptors on the surface of most immune cells. The immunosuppression by endogenously-produced adenosine is pathophysiologically significant since inactivation of A2A/A2B adenosine receptor (A2AR/A2BR) and adenosine-producing ecto-enzymes CD39/CD73 results in the higher intensity of immune response and exaggeration of inflammatory damage. Regulatory T cells (Treg) can generate extracellular adenosine, which is implicated in the immunoregulatory activity of Tregs. Interestingly, adenosine has been shown to increase the numbers of Tregs and further promotes their immunoregulatory activity. A2AR-deficiency in Tregs reduces their immunosuppressive efficacy in vivo. Thus, adenosine is not only directly and instantly inhibiting to the immune response through interaction with A2AR/A2BR on the effector cells, but also adenosine signaling can recruit other immunoregulatory mechanisms, including Tregs. Such interaction between adenosine and Tregs suggests the presence of a positive feedback mechanism, which further promotes negative regulation of immune system through the establishment of immunosuppressive microenvironment.
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Affiliation(s)
- Akio Ohta
- New England Inflammation and Tissue Protection Institute, Northeastern University , Boston, MA , USA
| | - Michail Sitkovsky
- New England Inflammation and Tissue Protection Institute, Northeastern University , Boston, MA , USA
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Muller-Haegele S, Muller L, Whiteside TL. Immunoregulatory activity of adenosine and its role in human cancer progression. Expert Rev Clin Immunol 2014; 10:897-914. [DOI: 10.1586/1744666x.2014.915739] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Friebe D, Yang T, Schmidt T, Borg N, Steckel B, Ding Z, Schrader J. Purinergic signaling on leukocytes infiltrating the LPS-injured lung. PLoS One 2014; 9:e95382. [PMID: 24748324 PMCID: PMC3991673 DOI: 10.1371/journal.pone.0095382] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/26/2014] [Indexed: 01/11/2023] Open
Abstract
Extracellular nucleotides and nucleosides have been implicated as important signaling molecules in the pathogenesis of acute lung injury (ALI). While adenosine is known to inhibit T cell activation, little information is available as to ATP and NAD degrading enzymes, the expression of ATP and adenosine receptors/transporters in different T cell subsets. ALI was induced by challenging mice with intra-tracheal instillation of 60 µl (3 µg/g) LPS. After 3 d and 7 d blood, lung tissue and bronchoalveolar lavage was collected and immune cells were analyzed using flow cytometry. The transcriptional phenotype of T helper cells, cytotoxic and regulatory T cells sorted by FACS was assessed by measuring the expression profile of 28 genes related to purinergic signaling using TaqMan Array Micro Fluidic Cards. Catabolism of ATP, NAD and cAMP by activated CD4+ T cells was evaluated by HPLC. CD73 was found to be highly abundant on lymphoid cells with little abundance on myeloid cells, while the opposite was true for CD39. After ALI, the abundance of CD39 and CD73 significantly increased on all T cell subsets derived from lung tissue and bronchoalveolar space. Expression analysis in T cell subsets of the lung revealed ATP (Cd39, Cd73) and NAD (Cd38, Cd157, Cd296, Pc-1) degrading enzymes. However, only transcription of Cd38, Cd39, Cd73, Ent1 and A2a receptor was significantly upregulated after ALI in T helper cells. CD4+ T cells from injured lung rapidly metabolized extracellular ATP to AMP and adenosine but not NAD or cAMP. These findings show that lung T cells – the dominant cell fraction in the later phase of ALI – exhibit a unique expression pattern of purinergic signaling molecules. Adenosine is formed by T cells at an enhanced rate from ATP but not from NAD and together with upregulated A2a receptor is likely to modulate the healing process after acute lung injury.
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Affiliation(s)
- Daniela Friebe
- Department of Molecular Cardiology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Tao Yang
- Department of Molecular Cardiology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- Department of Anesthesiology and Intensive Care Medicine, Changhai Hospital, Second Military Medical University, Shanghai, PR China
| | - Timo Schmidt
- Department of Molecular Cardiology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Nadine Borg
- Department of Molecular Cardiology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Bodo Steckel
- Department of Molecular Cardiology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Zhaoping Ding
- Department of Molecular Cardiology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
| | - Jürgen Schrader
- Department of Molecular Cardiology, Heinrich-Heine-University Düsseldorf, Düsseldorf, Germany
- * E-mail:
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82
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Aherne CM, Collins CB, Eltzschig HK. Netrin-1 guides inflammatory cell migration to control mucosal immune responses during intestinal inflammation. Tissue Barriers 2014; 1:e24957. [PMID: 24665394 PMCID: PMC3879190 DOI: 10.4161/tisb.24957] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 04/26/2013] [Accepted: 05/06/2013] [Indexed: 12/26/2022] Open
Abstract
The intestinal epithelium is a dynamic barrier playing an active role in intestinal homeostasis and inflammation. Intestinal barrier function is dysregulated during inflammatory bowel disease (IBD), with epithelial cells playing a significant part in generating an inflammatory milieu through the release of signals that attract leukocytes to the intestinal lamina propria. However, it is increasingly appreciated that the intestinal epithelium mediates a counterbalancing response to drive resolution. Drawing analogies with neuronal development, where the balance of chemoattractive and chemorepellent signals is key to directed neuronal movement it has been postulated that such secreted cues play a role in leukocyte migration. Netrin-1 is one of the best-described neuronal guidance molecules, which has been shown to play a significant role in directed migration of leukocytes. Prior to our study the potential role of netrin-1 in IBD was poorly characterized. We defined netrin-1 as an intestinal epithelial-derived protein capable of limiting neutrophil recruitment to attenuate acute colitis. Our study highlights that the intestinal epithelium releases factors during acute inflammation that are responsible for fine-tuning the immune response. Exploration of these epithelial-mediated protective mechanisms will shed light on the complexity of the intestinal epithelial barrier in health and disease.
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Affiliation(s)
- Carol M Aherne
- Mucosal Inflammation Program; Department of Anesthesiology and Perioperative Medicine; University of Colorado Anschutz Medical Campus; Aurora, CO USA
| | - Colm B Collins
- Department of Pediatrics; Children's Hospital Colorado; Aurora, CO USA
| | - Holger K Eltzschig
- Mucosal Inflammation Program; Department of Anesthesiology and Perioperative Medicine; University of Colorado Anschutz Medical Campus; Aurora, CO USA
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Gonzales JN, Gorshkov B, Varn MN, Zemskova MA, Zemskov EA, Sridhar S, Lucas R, Verin AD. Protective effect of adenosine receptors against lipopolysaccharide-induced acute lung injury. Am J Physiol Lung Cell Mol Physiol 2014; 306:L497-507. [PMID: 24414256 DOI: 10.1152/ajplung.00086.2013] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Acute lung injury and acute respiratory distress syndrome (ALI/ARDS) affect 200,000 people a year in the USA. Pulmonary vascular and specifically endothelial cell (EC) barrier compromise is a hallmark of these diseases. We have recently shown that extracellular adenosine enhances human pulmonary (EC) barrier via activation of adenosine receptors (ARs) in cell cultures. On the basis of these data, we hypothesized that activation of ARs might exert barrier-protective effects in a model of ALI/ARDS in mice. To test this hypothesis, we examined the effects of pre- and posttreatment of adenosine and 5'-N-ethylcarboxamidoadenosine (NECA), a nonselective stable AR agonist, on LPS-induced lung injury. Mice were given vehicle or LPS intratracheally followed by adenosine, NECA, or vehicle instilled via the internal jugular vein. Postexperiment cell counts, Evans Blue Dye albumin (EBDA) extravasation, levels of proteins, and inflammatory cytokines were analyzed. Harvested lungs were used for histology and myeloperoxidase studies. Mice challenged with LPS alone demonstrated an inflammatory response typical of ALI. Cell counts, EBDA extravasation, as well as levels of proteins and inflammatory cytokines were decreased in adenosine-treated mice. Histology displayed reduced infiltration of neutrophils. NECA had a similar effect on LPS-induced vascular barrier compromise. Importantly, posttreatment with adenosine or NECA recovers lung vascular barrier and reduces inflammation induced by LPS challenge. Furthermore, adenosine significantly attenuated protein degradation of A2A and A3 receptors induced by LPS. Collectively, our results demonstrate that activation of ARs protects and restores vascular barrier functions and reduces inflammation in LPS-induced ALI.
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Affiliation(s)
- Joyce N Gonzales
- Assistant Prof. of Medicine, Div. of Pulmonary and Critical Care Medicine, Georgia Regents Univ., Rm. BBR-5513, 1120 15th St., Augusta, GA 30912.
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84
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Tak E, Ridyard D, Kim JH, Zimmerman M, Werner T, Wang XX, Shabeka U, Seo SW, Christians U, Klawitter J, Moldovan R, Garcia G, Levi M, Haase V, Ravid K, Eltzschig HK, Grenz A. CD73-dependent generation of adenosine and endothelial Adora2b signaling attenuate diabetic nephropathy. J Am Soc Nephrol 2013; 25:547-63. [PMID: 24262796 DOI: 10.1681/asn.2012101014] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Nucleotide phosphohydrolysis by the ecto-5'-nucleotidase (CD73) is the main source for extracellular generation of adenosine. Extracellular adenosine subsequently signals through four distinct adenosine A receptors (Adora1, Adora2a, Adora2b, or Adora3). Here, we hypothesized a functional role for CD73-dependent generation and concomitant signaling of extracellular adenosine during diabetic nephropathy. CD73 transcript and protein levels were elevated in the kidneys of diabetic mice. Genetic deletion of CD73 was associated with more severe diabetic nephropathy, whereas treatment with soluble nucleotidase was therapeutic. Transcript levels of renal adenosine receptors showed a selective induction of Adora2b during diabetic nephropathy. In a transgenic reporter mouse, Adora2b expression localized to the vasculature and increased after treatment with streptozotocin. Adora2b(-/-) mice experienced more severe diabetic nephropathy, and studies in mice with tissue-specific deletion of Adora2b in tubular epithelia or vascular endothelia implicated endothelial Adora2b signaling in protection from diabetic nephropathy. Finally, treatment with a selective Adora2b agonist (BAY 60-6583) conveyed potent protection from diabetes-associated kidney disease. Taken together, these findings implicate CD73-dependent production of extracellular adenosine and endothelial Adora2b signaling in kidney protection during diabetic nephropathy.
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85
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Eckle T, Brodsky K, Bonney M, Packard T, Han J, Borchers CH, Mariani TJ, Kominsky DJ, Mittelbronn M, Eltzschig HK. HIF1A reduces acute lung injury by optimizing carbohydrate metabolism in the alveolar epithelium. PLoS Biol 2013; 11:e1001665. [PMID: 24086109 DOI: 10.1371/journal.pbio.1001665] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2013] [Accepted: 08/12/2013] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND While acute lung injury (ALI) contributes significantly to critical illness, it resolves spontaneously in many instances. The majority of patients experiencing ALI require mechanical ventilation. Therefore, we hypothesized that mechanical ventilation and concomitant stretch-exposure of pulmonary epithelia could activate endogenous pathways important in lung protection. METHODS AND FINDINGS To examine transcriptional responses during ALI, we exposed pulmonary epithelia to cyclic mechanical stretch conditions--an in vitro model resembling mechanical ventilation. A genome-wide screen revealed a transcriptional response similar to hypoxia signaling. Surprisingly, we found that stabilization of hypoxia-inducible factor 1A (HIF1A) during stretch conditions in vitro or during ventilator-induced ALI in vivo occurs under normoxic conditions. Extension of these findings identified a functional role for stretch-induced inhibition of succinate dehydrogenase (SDH) in mediating normoxic HIF1A stabilization, concomitant increases in glycolytic capacity, and improved tricarboxylic acid (TCA) cycle function. Pharmacologic studies with HIF activator or inhibitor treatment implicated HIF1A-stabilization in attenuating pulmonary edema and lung inflammation during ALI in vivo. Systematic deletion of HIF1A in the lungs, endothelia, myeloid cells, or pulmonary epithelia linked these findings to alveolar-epithelial HIF1A. In vivo analysis of ¹³C-glucose metabolites utilizing liquid-chromatography tandem mass-spectrometry demonstrated that increases in glycolytic capacity, improvement of mitochondrial respiration, and concomitant attenuation of lung inflammation during ALI were specific for alveolar-epithelial expressed HIF1A. CONCLUSIONS These studies reveal a surprising role for HIF1A in lung protection during ALI, where normoxic HIF1A stabilization and HIF-dependent control of alveolar-epithelial glucose metabolism function as an endogenous feedback loop to dampen lung inflammation.
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Affiliation(s)
- Tobias Eckle
- Organ Protection Program, Department of Anesthesiology, University of Colorado School of Medicine, Denver, Colorado, United States of America
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Greer S, Page CW, Joshi T, Yan D, Newton R, Giembycz MA. Concurrent agonism of adenosine A2B and glucocorticoid receptors in human airway epithelial cells cooperatively induces genes with anti-inflammatory potential: a novel approach to treat chronic obstructive pulmonary disease. J Pharmacol Exp Ther 2013; 346:473-85. [PMID: 23820127 DOI: 10.1124/jpet.113.206284] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is a neutrophilic inflammatory disorder that is weakly responsive to glucocorticoids. Identification of ways to enhance the anti-inflammatory activity of glucocorticoids is, therefore, a major research objective. Adenosine receptor agonists that target the A2B-receptor subtype are efficacious in several cell-based assays and preclinical models of inflammation. Accordingly, the present study was designed to determine if a selective A2B-receptor agonist, 2-[6-amino-3,5-dicyano-4-[4-(cyclopropylmethoxy)phenyl]pyridin-2-ylsulphanyl]acetamide (Bay 60-6583), and a glucocorticoid, dexamethasone, in combination display putative anti-inflammatory activity that is superior to either drug alone. In BEAS-2B human airway epithelial cells stably transfected with cAMP-response element (CRE) and glucocorticoid response element (GRE) reporter constructs, Bay 60-6583 promoted CRE-dependent transcription and enhanced GRE-dependent transcription by an adenosine A2B-receptor-mediated mechanism that was associated with cAMP formation and abolished by an inhibitor of cAMP-dependent protein kinase. Analysis of the concentration-response relationship that described the enhancement of GRE-dependent transcription showed that Bay 60-6583 increased the magnitude of response without affecting the potency of dexamethasone. Bay 60-6583 and dexamethasone also induced a panel of genes that, collectively, could have benefit in COPD. These were categorized into genes that were induced in a positive cooperative manner (RGS2, p57(kip2)), an additive manner (TTP, BRL-1), or by Bay 60-6583 (CD200, CRISPLD2, SOCS3) or dexamethasone (GILZ) only. Thus, the gene induction "fingerprints" produced by Bay 60-6583 and dexamethasone, alone and in combination, were distinct. Collectively, through their actions on gene expression, an adenosine A2B-receptor agonist and a glucocorticoid administered together may have utility in the treatment of inflammatory disorders that respond suboptimally to glucocorticoids as a monotherapy.
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Affiliation(s)
- Stephanie Greer
- Airways Inflammation Research Group, Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, University of Calgary, Calgary, Alberta, Canada
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Ehrentraut H, Clambey ET, McNamee EN, Brodsky KS, Ehrentraut SF, Poth JM, Riegel AK, Westrich JA, Colgan SP, Eltzschig HK. CD73+ regulatory T cells contribute to adenosine-mediated resolution of acute lung injury. FASEB J 2013; 27:2207-19. [PMID: 23413361 PMCID: PMC3659359 DOI: 10.1096/fj.12-225201] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 02/04/2013] [Indexed: 12/22/2022]
Abstract
Acute lung injury (ALI) is characterized by alveolar injury and uncontrolled inflammation. Since most cases of ALI resolve spontaneously, understanding the endogenous mechanisms that promote ALI resolution is important to developing effective therapies. Previous studies have implicated extracellular adenosine signaling in tissue adaptation and wound healing. Therefore, we hypothesized a functional contribution for the endogenous production of adenosine during ALI resolution. As a model, we administered intratracheal LPS and observed peak lung injury at 3 d, with resolution by d 14. Treatment with pegylated adenosine-deaminase to enhance extracellular adenosine breakdown revealed impaired ALI resolution. Similarly, genetic deletion of cd73, the pacemaker for extracellular adenosine generation, was associated with increased mortality (0% wild-type and 40% in cd73(-/-) mice; P<0.05) and failure to resolve ALI adequately. Studies of inflammatory cell trafficking into the lungs during ALI resolution revealed that regulatory T cells (Tregs) express the highest levels of CD73. While Treg numbers in cd73(-/-) mice were similar to controls, cd73-deficient Tregs had attenuated immunosuppressive functions. Moreover, adoptive transfer of cd73-deficient Tregs into Rag(-/-) mice emulated the observed phenotype in cd73(-/-) mice, while transfer of wild-type Tregs was associated with normal ALI resolution. Together, these studies implicate CD73-dependent adenosine generation in Tregs in promoting ALI resolution.
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Affiliation(s)
- Heidi Ehrentraut
- Department of Anesthesiology and
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Bonn, Germany
| | | | | | | | - Stefan F. Ehrentraut
- Department of Medicine, Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado, USA; and
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Bonn, Germany
| | - Jens M. Poth
- Department of Anesthesiology and
- Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Bonn, Germany
| | | | | | - Sean P. Colgan
- Department of Medicine, Mucosal Inflammation Program, University of Colorado School of Medicine, Aurora, Colorado, USA; and
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Protective role for netrin-1 during diabetic nephropathy. J Mol Med (Berl) 2013; 91:1071-80. [PMID: 23636509 DOI: 10.1007/s00109-013-1041-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 04/03/2013] [Accepted: 04/11/2013] [Indexed: 02/08/2023]
Abstract
Recent studies implicate neuronal guidance molecules in the orchestration of inflammatory events. For example, previous studies demonstrate a functional role for netrin-1 in attenuating acute kidney injury. Here, we hypothesized a kidney-protective role for netrin-1 during chronic kidney disease, such as occurs during diabetic nephropathy. To study the role of netrin-1 during diabetic nephropathy, we induced diabetes in mice at the age of 8 weeks by streptocotozin (STZ) treatment. Sixteen weeks after STZ treatment, we examined the kidneys. Initial studies in wild-type mice demonstrated robust induction of renal, urinary, and plasma netrin-1 protein levels during diabetic nephropathy. Subsequent genetic studies in mice with partial netrin-1 deficiency (Ntrn1(+/-) mice) revealed a more severe degree of diabetic nephropathy, including more severe loss of kidney function (albuminuria, glomerular filtration rate, histology). We subsequently performed pharmacologic studies with recombinant netrin-1 treatment given continuously via osmotic pump. Indeed, netrin-1 treatment was associated with attenuated albuminuria and improved histologic scores for diabetic nephropathy compared to controls. Consistent with previous studies implicating purinergic signaling in netrin-1-elicited tissue protection, mice deficient in the Adora2b adenosine receptor were not protected. Taken together, these studies demonstrate a functional role for endogenous netrin-1 in attenuating diabetic kidney disease.
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90
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Eltzschig HK, Bonney SK, Eckle T. Attenuating myocardial ischemia by targeting A2B adenosine receptors. Trends Mol Med 2013; 19:345-54. [PMID: 23540714 DOI: 10.1016/j.molmed.2013.02.005] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 02/12/2013] [Accepted: 02/20/2013] [Indexed: 02/06/2023]
Abstract
Myocardial ischemia is associated with profound tissue hypoxia due to an imbalance in oxygen supply and demand, and studies of hypoxia-elicited adaptive responses during myocardial ischemia revealed a cardioprotective role for the signaling molecule adenosine. In ischemic human hearts, the A2B adenosine receptor (ADORA2B) is selectively induced. Functional studies in genetic models show that ADORA2B signaling attenuates myocardial infarction by adapting metabolism towards more oxygen efficient utilization of carbohydrates. This adenosine-mediated cardio-adaptive response involves the transcription factor hypoxia-inducible factor HIF1α and the circadian rhythm protein PER2. In this article, we discuss advances in the understanding of adenosine-elicited cardioprotection with particular emphasis on ADORA2B, its downstream targets, and the implications for novel strategies to prevent or treat myocardial ischemia.
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Affiliation(s)
- Holger K Eltzschig
- Mucosal Inflammation Program, Department of Anesthesiology, University of Colorado School of Medicine, Aurora, CO, USA.
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91
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Targeting the hypoxia-adenosinergic signaling pathway to improve the adoptive immunotherapy of cancer. J Mol Med (Berl) 2013; 91:147-55. [PMID: 23334369 DOI: 10.1007/s00109-013-1001-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2012] [Revised: 01/10/2013] [Accepted: 01/13/2013] [Indexed: 12/12/2022]
Abstract
The recent approval by the FDA of cancer vaccines and drugs that blockade immunological negative regulators has further enhanced interest in promising approaches of the immunotherapy of cancer. However, the disappointingly short life extension has also underscored the need to better understand the mechanisms that prevent tumor rejection and survival even after the blockade of immunological negative regulators. Here, we describe the implications of the "metabolism-based" immunosuppressive mechanism, where the local tissue hypoxia-driven accumulation of extracellular adenosine triggers suppression via A2 adenosine receptors on the surface of activated immune cells. This molecular pathway is of critical importance in mechanisms of immunosuppression in inflamed and cancerous tissue microenvironments. The protection of tumors by tumor-generated extracellular adenosine and A2 adenosine receptors could be the misguided application of the normal tissue-protecting mechanism that limits excessive collateral damage to vital organs during the anti-pathogen immune response. The overview of the current state of the art regarding the immunosuppressive effects of extracellular adenosine is followed by a historical perspective of studies focused on the elucidation of the physiological negative regulators that protect tissues of vital organs from excessive collateral damage, but, as a trade-off, may also weaken the anti-pathogen effector functions and negate the attempts of anti-tumor immune cells to destroy cancerous cells.
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Grenz A, Kim JH, Bauerle JD, Tak E, Eltzschig HK, Clambey ET. Adora2b adenosine receptor signaling protects during acute kidney injury via inhibition of neutrophil-dependent TNF-α release. THE JOURNAL OF IMMUNOLOGY 2012; 189:4566-73. [PMID: 23028059 DOI: 10.4049/jimmunol.1201651] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Renal ischemia is among the leading causes of acute kidney injury (AKI). Previous studies have shown that extracellular adenosine is a prominent tissue-protective cue elicited during ischemia, including signaling events through the adenosine receptor 2b (Adora2b). To investigate the functional role of Adora2b signaling in cytokine-mediated inflammatory pathways, we screened wild-type and Adora2b-deficient mice undergoing renal ischemia for expression of a range of inflammatory cytokines. These studies demonstrated a selective and robust increase of TNF-α levels in Adora2b-deficient mice following renal ischemia and reperfusion. Based on these findings, we next sought to understand the contribution of TNF-α on ischemic AKI through a combination of loss- and gain-of-function studies. Loss of TNF-α, through either Ab blockade or study of Tnf-α-deficient animals, resulted in significantly attenuated tissue injury and improved kidney function following renal ischemia. Conversely, transgenic mice with overexpression of TNF-α had significantly pronounced susceptibility to AKI. Furthermore, neutrophil depletion or reconstitution of Adora2b(-/-) mice with Tnf-α-deficient neutrophils rescued their phenotype. In total, these data demonstrate a critical role of adenosine signaling in constraining neutrophil-dependent production of TNF-α and implicate therapies targeting TNF-α in the treatment of ischemic AKI.
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Affiliation(s)
- Almut Grenz
- Mucosal Inflammation Program, Department of Anesthesiology, University of Colorado Denver, Aurora, CO 80045, USA
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