1
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Maurya DK, Sharma D, Sandur SK. Hypoxia induces dichotomous and reversible attenuation of T cell responses through reactive oxygen species-dependent phenotype redistribution and delay in lymphoblast proliferation. Free Radic Res 2023; 57:1-13. [PMID: 36947008 DOI: 10.1080/10715762.2023.2178918] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
As T cells transit between blood, lymphoid organs, and peripheral tissues, they experience varied levels of oxygen/hypoxia in inflamed tissues, skin, intestinal lining, and secondary lymphoid organs. Critical illness among COVID-19 patients is also associated with transient hypoxia and attenuation of T cell responses. Hypoxia is the fulcrum of altered metabolism, impaired functions, and cessation of growth of a subset of T cells. However, the restoration of normal T cell functions following transient hypoxia and kinetics of their phenotype-redistribution is not completely understood. Here, we sought to understand kinetics and reversibility of dichotomous T cell responses under sustained and transient hypoxia. We found that a subset of activated T cells accumulated as lymphoblasts under hypoxia. Further, T cells showed the normal expression of activation markers CD25 and CD69 and inflammatory cytokine secretion but a subset exhibited delayed cell proliferation under hypoxia. Increased levels of reactive oxygen species (ROS) in cytosol and mitochondria were seen during dichotomous and reversible attenuation of T cell response under hypoxia. Cell cycle analysis revealed maximum levels of cytosolic and mitochondrial ROS in dividing T cells (in S, G2, or M phase). Hypoxic T cells also showed specific attenuation of activation induced memory phenotype conversion without affecting naïve and activated T cells. Hypoxia-related attenuation of T cell proliferation was also found to be reversible in an allogeneic leukocyte specific mixed lymphocyte reaction assay. In summary, our results show that hypoxia induces a reversible delay in proliferation of a subset of T cells which is associated with obliteration of memory phenotype and specific increase in cytosolic/mitochondrial ROS levels in actively dividing subpopulation. Thus, the transient reoxygenation of hypoxic patients may restore normal T cell responses.
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Affiliation(s)
- Dharmendra Kumar Maurya
- Radiation Biology & Health Sciences Division, Bio-Science Group, Bhabha Atomic Research Centre, Mumbai, India
- Homi Bhabha National Institute, Mumbai, India
| | - Deepak Sharma
- Radiation Biology & Health Sciences Division, Bio-Science Group, Bhabha Atomic Research Centre, Mumbai, India
- Homi Bhabha National Institute, Mumbai, India
| | - Santosh Kumar Sandur
- Radiation Biology & Health Sciences Division, Bio-Science Group, Bhabha Atomic Research Centre, Mumbai, India
- Homi Bhabha National Institute, Mumbai, India
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2
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Chen Z, Han F, Du Y, Shi H, Zhou W. Hypoxic microenvironment in cancer: molecular mechanisms and therapeutic interventions. Signal Transduct Target Ther 2023; 8:70. [PMID: 36797231 PMCID: PMC9935926 DOI: 10.1038/s41392-023-01332-8] [Citation(s) in RCA: 93] [Impact Index Per Article: 93.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Revised: 12/20/2022] [Accepted: 01/18/2023] [Indexed: 02/18/2023] Open
Abstract
Having a hypoxic microenvironment is a common and salient feature of most solid tumors. Hypoxia has a profound effect on the biological behavior and malignant phenotype of cancer cells, mediates the effects of cancer chemotherapy, radiotherapy, and immunotherapy through complex mechanisms, and is closely associated with poor prognosis in various cancer patients. Accumulating studies have demonstrated that through normalization of the tumor vasculature, nanoparticle carriers and biocarriers can effectively increase the oxygen concentration in the tumor microenvironment, improve drug delivery and the efficacy of radiotherapy. They also increase infiltration of innate and adaptive anti-tumor immune cells to enhance the efficacy of immunotherapy. Furthermore, drugs targeting key genes associated with hypoxia, including hypoxia tracers, hypoxia-activated prodrugs, and drugs targeting hypoxia-inducible factors and downstream targets, can be used for visualization and quantitative analysis of tumor hypoxia and antitumor activity. However, the relationship between hypoxia and cancer is an area of research that requires further exploration. Here, we investigated the potential factors in the development of hypoxia in cancer, changes in signaling pathways that occur in cancer cells to adapt to hypoxic environments, the mechanisms of hypoxia-induced cancer immune tolerance, chemotherapeutic tolerance, and enhanced radiation tolerance, as well as the insights and applications of hypoxia in cancer therapy.
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Affiliation(s)
- Zhou Chen
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China.,The First Hospital of Lanzhou University, Lanzhou, Gansu, China
| | - Fangfang Han
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China.,The First Hospital of Lanzhou University, Lanzhou, Gansu, China
| | - Yan Du
- The Second Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China
| | - Huaqing Shi
- The Second Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China
| | - Wence Zhou
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China. .,Lanzhou University Sencond Hospital, Lanzhou, Gansu, China.
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3
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Stirling ER, Terabe M, Wilson AS, Kooshki M, Yamaleyeva LM, Alexander-Miller MA, Zhang W, Miller LD, Triozzi PL, Soto-Pantoja DR. Targeting the CD47/thrombospondin-1 signaling axis regulates immune cell bioenergetics in the tumor microenvironment to potentiate antitumor immune response. J Immunother Cancer 2022; 10:e004712. [PMID: 36418073 PMCID: PMC9685258 DOI: 10.1136/jitc-2022-004712] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/12/2022] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND CD47 is an integral membrane protein that alters adaptive immunosurveillance when bound to the matricellular glycoprotein thrombospondin-1 (TSP1). We examined the impact of the CD47/TSP1 signaling axis on melanoma patient response to anti-PD-1 therapy due to alterations in T cell activation, proliferation, effector function, and bioenergetics. METHODS A syngeneic B16 mouse melanoma model was performed to determine if targeting CD47 as monotherapy or in combination with anti-PD-1 impacted tumor burden. Cytotoxic (CD8+) T cells from Pmel-1 transgenic mice were used for T cell activation, cytotoxic T lymphocyte, and cellular bioenergetic assays. Single-cell RNA-sequencing, ELISA, and flow cytometry was performed on peripheral blood mononuclear cells and plasma of melanoma patients receiving anti-PD-1 therapy to examine CD47/TSP1 expression. RESULTS Human malignant melanoma tissue had increased CD47 and TSP1 expression within the tumor microenvironment compared with benign tissue. Due to the negative implications CD47/TSP1 can have on antitumor immune responses, we targeted CD47 in a melanoma model and observed a decrease in tumor burden due to increased tumor oxygen saturation and granzyme B secreting CD8+ T cells compared with wild-type tumors. Additionally, Pmel-1 CD8+ T cells exposed to TSP1 had reduced activation, proliferation, and effector function against B16 melanoma cells. Targeting CD47 allowed CD8+ T cells to overcome this TSP1 interaction to sustain these functions. TSP1 exposed CD8+ T cells have a decreased rate of glycolysis; however, targeting CD47 restored glycolysis when CD8+ T cells were exposed to TSP1, suggesting CD47 mediated metabolic reprogramming of T cells. Additionally, non-responding patients to anti-PD-1 therapy had increased T cells expressing CD47 and circulating levels of TSP1 compared with responding patients. Since CD47/TSP1 signaling axis negatively impacts CD8+ T cells and non-responding patients to anti-PD-1 therapy have increased CD47/TSP1 expression, we targeted CD47 in combination with anti-PD-1 in a melanoma model. Targeting CD47 in combination with anti-PD-1 treatment further decreased tumor burden compared with monotherapy and control. CONCLUSION CD47/TSP1 expression could serve as a marker to predict patient response to immune checkpoint blockade treatment, and targeting this pathway may preserve T cell activation, proliferation, effector function, and bioenergetics to reduce tumor burden as a monotherapy or in combination with anti-PD-1.
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Affiliation(s)
- Elizabeth R Stirling
- Department of Cancer Biology, Wake Forest Univerisity School of Medicine, Winston-Salem, North Carolina, USA
| | - Masaki Terabe
- Neuro-Oncology Branch, National Cancer Institute, Bethesda, Maryland, USA
| | - Adam S Wilson
- Department of Surgery, Wake Forest Univerisity School of Medicine, Winston-Salem, North Carolina, USA
| | - Mitra Kooshki
- Department of Hematology & Oncology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
- Department of Radiation Oncology, Wake Forest University School of Medicine, WInston-Salem, North Carolina, USA
| | - Liliya M Yamaleyeva
- Department of Surgery, Wake Forest Univerisity School of Medicine, Winston-Salem, North Carolina, USA
| | - Martha A Alexander-Miller
- Department of Microbiology & Immunology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Wei Zhang
- Department of Cancer Biology, Wake Forest Univerisity School of Medicine, Winston-Salem, North Carolina, USA
- Atrium Health Wake Forest Baptist Medical Center, Comprehensive Cancer Center, Winston-Salem, North Carolina, USA
| | - Lance D Miller
- Department of Cancer Biology, Wake Forest Univerisity School of Medicine, Winston-Salem, North Carolina, USA
- Atrium Health Wake Forest Baptist Medical Center, Comprehensive Cancer Center, Winston-Salem, North Carolina, USA
| | - Pierre L Triozzi
- Department of Cancer Biology, Wake Forest Univerisity School of Medicine, Winston-Salem, North Carolina, USA
- Department of Hematology & Oncology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
- Atrium Health Wake Forest Baptist Medical Center, Comprehensive Cancer Center, Winston-Salem, North Carolina, USA
| | - David R Soto-Pantoja
- Department of Cancer Biology, Wake Forest Univerisity School of Medicine, Winston-Salem, North Carolina, USA
- Department of Surgery, Wake Forest Univerisity School of Medicine, Winston-Salem, North Carolina, USA
- Department of Radiation Oncology, Wake Forest University School of Medicine, WInston-Salem, North Carolina, USA
- Atrium Health Wake Forest Baptist Medical Center, Comprehensive Cancer Center, Winston-Salem, North Carolina, USA
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4
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How the Potassium Channel Response of T Lymphocytes to the Tumor Microenvironment Shapes Antitumor Immunity. Cancers (Basel) 2022; 14:cancers14153564. [PMID: 35892822 PMCID: PMC9330401 DOI: 10.3390/cancers14153564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 07/18/2022] [Accepted: 07/20/2022] [Indexed: 12/10/2022] Open
Abstract
Competent antitumor immune cells are fundamental for tumor surveillance and combating active cancers. Once established, tumors generate a tumor microenvironment (TME) consisting of complex cellular and metabolic elements that serve to suppress the function of antitumor immune cells. T lymphocytes are key cellular elements of the TME. In this review, we explore the role of ion channels, particularly K+ channels, in mediating the suppressive effects of the TME on T cells. First, we will review the complex network of ion channels that mediate Ca2+ influx and control effector functions in T cells. Then, we will discuss how multiple features of the TME influence the antitumor capabilities of T cells via ion channels. We will focus on hypoxia, adenosine, and ionic imbalances in the TME, as well as overexpression of programmed cell death ligand 1 by cancer cells that either suppress K+ channels in T cells and/or benefit from regulating these channels’ activity, ultimately shaping the immune response. Finally, we will review some of the cancer treatment implications related to ion channels. A better understanding of the effects of the TME on ion channels in T lymphocytes could promote the development of more effective immunotherapies, especially for resistant solid malignancies.
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5
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Hypothermia after Perinatal Asphyxia Does Not Affect Genes Responsible for Amyloid Production in Neonatal Peripheral Lymphocytes. J Clin Med 2022; 11:jcm11123263. [PMID: 35743334 PMCID: PMC9225259 DOI: 10.3390/jcm11123263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 05/11/2022] [Accepted: 06/03/2022] [Indexed: 11/17/2022] Open
Abstract
In this study, the expression of the genes of the amyloid protein precursor, β-secretase, presenilin 1 and 2 by RT-PCR in the lymphocytes of newborns after perinatal asphyxia and perinatal asphyxia treated with hypothermia was analyzed at the age of 15-21 days. The relative quantification of Alzheimer's-disease-related genes was first performed by comparing the peripheral lymphocytes of non-asphyxia control versus those with asphyxia or asphyxia with hypothermia. In the newborns who had perinatal asphyxia, the peripheral lymphocytes presented a decreased expression of the amyloid protein precursor and β-secretase genes. On the other hand, the expression of the presenilin 1 and 2 genes increased in the studied group. The expression of the studied genes in the asphyxia group treated with hypothermia had an identical pattern of changes that were not statistically significant to the asphyxia group. This suggests that the expression of the genes involved in the metabolism of the amyloid protein precursor in the peripheral lymphocytes may be a biomarker of progressive pathological processes in the brain after asphyxia that are not affected by hypothermia. These are the first data in the world showing the role of hypothermia in the gene changes associated with Alzheimer's disease in the peripheral lymphocytes of newborns after asphyxia.
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6
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Stirling ER, Bronson SM, Mackert JD, Cook KL, Triozzi PL, Soto-Pantoja DR. Metabolic Implications of Immune Checkpoint Proteins in Cancer. Cells 2022; 11:179. [PMID: 35011741 PMCID: PMC8750774 DOI: 10.3390/cells11010179] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 12/20/2021] [Accepted: 12/29/2021] [Indexed: 12/29/2022] Open
Abstract
Expression of immune checkpoint proteins restrict immunosurveillance in the tumor microenvironment; thus, FDA-approved checkpoint inhibitor drugs, specifically PD-1/PD-L1 and CTLA-4 inhibitors, promote a cytotoxic antitumor immune response. Aside from inflammatory signaling, immune checkpoint proteins invoke metabolic reprogramming that affects immune cell function, autonomous cancer cell bioenergetics, and patient response. Therefore, this review will focus on the metabolic alterations in immune and cancer cells regulated by currently approved immune checkpoint target proteins and the effect of costimulatory receptor signaling on immunometabolism. Additionally, we explore how diet and the microbiome impact immune checkpoint blockade therapy response. The metabolic reprogramming caused by targeting these proteins is essential in understanding immune-related adverse events and therapeutic resistance. This can provide valuable information for potential biomarkers or combination therapy strategies targeting metabolic pathways with immune checkpoint blockade to enhance patient response.
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Affiliation(s)
- Elizabeth R. Stirling
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.R.S.); (K.L.C.); (P.L.T.)
| | - Steven M. Bronson
- Department of Pathology, Section of Comparative Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA;
- Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Jessica D. Mackert
- Department of Surgery, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA;
| | - Katherine L. Cook
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.R.S.); (K.L.C.); (P.L.T.)
- Department of Surgery, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA;
- Wake Forest School of Medicine Comprehensive Cancer Center, Winston-Salem, NC 27157, USA
| | - Pierre L. Triozzi
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.R.S.); (K.L.C.); (P.L.T.)
- Wake Forest School of Medicine Comprehensive Cancer Center, Winston-Salem, NC 27157, USA
- Department of Hematology and Oncology, Wake Forest School of Medicine Comprehensive Cancer Center, Winston-Salem, NC 27157, USA
| | - David R. Soto-Pantoja
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA; (E.R.S.); (K.L.C.); (P.L.T.)
- Department of Surgery, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA;
- Wake Forest School of Medicine Comprehensive Cancer Center, Winston-Salem, NC 27157, USA
- Department of Radiation Oncology, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
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7
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Gawali VS, Chimote AA, Newton HS, Feria-Garzón MG, Chirra M, Janssen EM, Wise-Draper TM, Conforti L. Immune Checkpoint Inhibitors Regulate K + Channel Activity in Cytotoxic T Lymphocytes of Head and Neck Cancer Patients. Front Pharmacol 2021; 12:742862. [PMID: 34512366 PMCID: PMC8429813 DOI: 10.3389/fphar.2021.742862] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 08/16/2021] [Indexed: 12/27/2022] Open
Abstract
Programmed death receptor-1 (PD-1) and its ligand (PD-L1) interaction negatively regulates T cell function in head and neck squamous cell carcinoma (HNSCC). Overexpression of PD-1 reduces intracellular Ca2+ fluxes, and thereby T cell effector functions. In HNSCC patients, PD-1 blockade increases KCa3.1 and Kv1.3 activity along with Ca2+ signaling and mobility in CD8+ peripheral blood T cells (PBTs). The mechanism by which PD-L1/PD-1 interaction regulates ion channel function is not known. We investigated the effects of blocking PD-1 and PD-L1 on ion channel functions and intracellular Ca2+ signaling in CD8+ PBTs of HNSCC patients and healthy donors (HDs) using single-cell electrophysiology and live microscopy. Anti-PD-1 and anti-PD-L1 antibodies increase KCa3.1 and Kv1.3 function in CD8+ PBTs of HNSCC patients. Anti-PD-1 treatment increases Ca2+ fluxes in a subset of HSNCC patients. In CD8+ PBTs of HDs, exposure to PD-L1 reduces KCa3.1 activity and Ca2+ signaling, which were restored by anti-PD-1 treatment. The PD-L1-induced inhibition of KCa3.1 channels was rescued by the intracellular application of the PI3 kinase modulator phosphatidylinositol 3-phosphate (PI3P) in patch-clamp experiments. In HNSCC CD8+ PBTs, anti-PD-1 treatment did not affect the expression of KCa3.1, Kv1.3, Ca2+ release activated Ca2+ (CRAC) channels, and markers of cell activation (CD69) and exhaustion (LAG-3 and TIM-3). Our data show that immune checkpoint blockade improves T cell function by increasing KCa3.1 and Kv1.3 channel activity in HNSCC patients.
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Affiliation(s)
- Vaibhavkumar S Gawali
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati, Cincinnati, OH, United States
| | - Ameet A Chimote
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati, Cincinnati, OH, United States
| | - Hannah S Newton
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati, Cincinnati, OH, United States
| | - Manuel G Feria-Garzón
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati, Cincinnati, OH, United States
| | - Martina Chirra
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati, Cincinnati, OH, United States
| | - Edith M Janssen
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States.,Immunology, Janssen Research and Development, Spring House, PA, United States
| | - Trisha M Wise-Draper
- Department of Internal Medicine, Division of Hematology Oncology, University of Cincinnati, Cincinnati, OH, United States
| | - Laura Conforti
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati, Cincinnati, OH, United States
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8
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Yoo HY, Kim SJ. Oxygen-dependent regulation of ion channels: acute responses, post-translational modification, and response to chronic hypoxia. Pflugers Arch 2021; 473:1589-1602. [PMID: 34142209 DOI: 10.1007/s00424-021-02590-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 05/15/2021] [Accepted: 05/30/2021] [Indexed: 12/19/2022]
Abstract
Oxygen is a vital element for the survival of cells in multicellular aerobic organisms such as mammals. Lack of O2 availability caused by environmental or pathological conditions leads to hypoxia. Active oxygen distribution systems (pulmonary and circulatory) and their neural control mechanisms ensure that cells and tissues remain oxygenated. However, O2-carrying blood cells as well as immune and various parenchymal cells experience wide variations in partial pressure of oxygen (PO2) in vivo. Hence, the reactive modulation of the functions of the oxygen distribution systems and their ability to sense PO2 are critical. Elucidating the physiological responses of cells to variations in PO2 and determining the PO2-sensing mechanisms at the biomolecular level have attracted considerable research interest in the field of physiology. Herein, we review the current knowledge regarding ion channel-dependent oxygen sensing and associated signalling pathways in mammals. First, we present the recent findings on O2-sensing ion channels in representative chemoreceptor cells as well as in other types of cells such as immune cells. Furthermore, we highlight the transcriptional regulation of ion channels under chronic hypoxia and its physiological implications and summarize the findings of studies on the post-translational modification of ion channels under hypoxic or ischemic conditions.
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Affiliation(s)
- Hae Young Yoo
- Department of Nursing, Chung-Ang University, Seoul, 06974, Republic of Korea
| | - Sung Joon Kim
- Department of Physiology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul, 03080, Republic of Korea. .,Ischemic/Hypoxic Disease Institute, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea.
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9
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Gryffin PA, Diaz RE. Effects of Tai Chi and running on blood oxygen saturation: a pilot study. JOURNAL OF COMPLEMENTARY & INTEGRATIVE MEDICINE 2021; 18:821-825. [PMID: 33793144 DOI: 10.1515/jcim-2020-0306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Accepted: 10/21/2020] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Large drops in blood oxygen saturation (SpO2) to levels as low as 84% was observed following Tai Chi practice, during a study on the effects of Tai Chi on SpO2. The objectives of the current pilot study were to determine if this was a statistically significant drop, and how SpO2 levels compared to an aerobic activity such as running, in pre, concurrent, and post measurements. METHODS Repeated measures of blood oxygen saturation (SpO2) were taken of a 50-year-old male before, during and for 1 min after TC and running. RESULTS Measurements of SpO2 before, during, and after TC resulted in a statistically significant increase in SpO2 during TC (p=1.69e-06), and a statistically significant (p=1.71e-06) brief momentary drop from resting levels, as low as 87% SpO2. Running showed no significant change in pre and post levels, with a significant change and decrease in SpO2 during running (p=1.1e-08), suggesting increased oxygen use by the large muscle groups during exercise. SpO2 returned to normal resting levels following running with no post drop. Results suggest a higher rate of oxygen metabolism during TC, with a potential effect on hypoxic (oxygen deficient) areas of the body. CONCLUSIONS Findings suggest direct and unique effects on enhanced blood oxygen saturation and oxygen metabolism, which may underlie benefits for conditions complicated by hypoxia, including cardiopulmonary disease, immunity, chronic pain, and arthritis.
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Affiliation(s)
| | - Rafael E Diaz
- California State University Sacramento, Sacramento, CA, USA
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10
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Newton HS, Gawali VS, Chimote AA, Lehn MA, Palackdharry SM, Hinrichs BH, Jandarov R, Hildeman D, Janssen EM, Wise-Draper TM, Conforti L. PD1 blockade enhances K + channel activity, Ca 2+ signaling, and migratory ability in cytotoxic T lymphocytes of patients with head and neck cancer. J Immunother Cancer 2020; 8:e000844. [PMID: 33060146 PMCID: PMC7566435 DOI: 10.1136/jitc-2020-000844] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/10/2020] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Immunotherapy has emerged as a promising treatment modality for head and neck squamous cell carcinoma (HNSCC). Pembrolizumab, an anti-programmed death 1 antibody, is an immunotherapy agent currently approved for metastatic HNSCC and curative intent clinical trials. Although clinical responses to pembrolizumab are promising, many patients fail to respond. However, it is well known that T cell cytotoxicity and chemotaxis are critically important in the elimination of HNSCC tumors. These functions depend on ion channel activity and downstream Ca2+ fluxing abilities, which are defective in patients with HNSCC. The purpose of this study was to elucidate the effects of pembrolizumab on potassium (K+) channel (KCa3.1 and Kv1.3) activity, Ca2+ fluxes, and chemotaxis in the cytotoxic T cells of patients with HNSCC and to determine their correlation with treatment response. METHODS Functional studies were conducted in CD8+ peripheral blood T cells (PBTs) and tumor infiltrating lymphocytes (TILs) from patients with HNSCC treated with pembrolizumab. Untreated patients with HNSCC were used as controls. The ion channel activity of CD8+ T cells was measured by patch-clamp electrophysiology; single-cell Ca2+ fluxing abilities were measured by live microscopy. Chemotaxis experiments were conducted in a three-dimensional collagen matrix. Pembrolizumab patients were stratified as responders or non-responders based on pathological response (percent of viable tumor remaining at resection; responders: ≤80% viable tumor; non-responders: >80% viable tumor). RESULTS Pembrolizumab increased K+ channel activity and Ca2+ fluxes in TILs independently of treatment response. However, in PBTs from responder patients there was an increased KCa3.1 activity immediately after pembrolizumab treatment that was accompanied by a characteristic increase in Kv1.3 and Ca2+ fluxes as compared with PBTs from non-responder patients. The effects on Kv1.3 and Ca2+ were prolonged and persisted after tumor resection. Chemotaxis was also improved in responder patients' PBTs. Unlike non-responders' PBTs, pembrolizumab increased their ability to chemotax in a tumor-like, adenosine-rich microenvironment immediately after treatment, and additionally they maintained an efficient chemotaxis after tumor resection. CONCLUSIONS Pembrolizumab enhanced K+ channel activity, Ca2+ fluxes and chemotaxis of CD8+ T cells in patients with HNSCC, with a unique pattern of response in responder patients that is conducive to the heightened functionality of their cytotoxic T cells.
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Affiliation(s)
- Hannah S Newton
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Vaibhavkumar S Gawali
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Ameet A Chimote
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Maria A Lehn
- Department of Internal Medicine, Division of Hematology/Oncology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Sarah M Palackdharry
- Department of Internal Medicine, Division of Hematology/Oncology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Benjamin H Hinrichs
- Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Roman Jandarov
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - David Hildeman
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Edith M Janssen
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
- Immunology, Janssen Research and Development, Spring House, Pennsylvania, USA
| | - Trisha M Wise-Draper
- Department of Internal Medicine, Division of Hematology/Oncology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Laura Conforti
- Department of Internal Medicine, Division of Nephrology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
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11
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Sureshbabu SK, Chaukar D, Chiplunkar SV. Hypoxia regulates the differentiation and anti-tumor effector functions of γδT cells in oral cancer. Clin Exp Immunol 2020; 201:40-57. [PMID: 32255193 DOI: 10.1111/cei.13436] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 02/29/2020] [Accepted: 03/10/2020] [Indexed: 12/16/2022] Open
Abstract
Hypoxia within the tumor microenvironment (TME) is a key factor contributing to immunosuppression in tumors, co-relating with poor treatment outcome and decreased overall survival in advanced oral cancer (OC) patients. Vδ2 is a dominant subset of gamma delta T cells (γδT cells) present in the peripheral blood which exhibits potent anti-tumor cytotoxicity and is evolving as a key player of anti-cancer cellular therapy. However, the fate of γδT cells in hypoxic oral tumors remains elusive. In the present study, we compared the effect of hypoxia (1% O2 ) and normoxia (21% O2 ) on the expansion, proliferation, activation status, cytokine secretion and cytotoxicity of γδT cells isolated from OC patients and healthy individuals. Hypoxia-exposed γδT cells exhibited reduced cytotoxicity against oral tumor cells. Our data demonstrated that hypoxia reduces the calcium efflux and the expression of degranulation marker CD107a in γδT cells, which explains the decreased anti-tumor cytotoxicity of γδT cells observed under hypoxia. Hypoxia-exposed γδT cells differentiated to γδT17 [γδ T cells that produce interleukin (IL)-17] cells, which corroborated our observations of increased γδT17 cells observed in the oral tumors. Co-culture of γδT cells with CD8 T cells in the presence of hypoxia showed that programmed cell death ligand 1 (PD-L1)high γδT cells brought about apoptosis of programmed cell death 1 (PD-1)high CD8 T cells which could be significantly reversed upon blocking PD-1. Thus, future immunotherapeutic treatment modality for oral cancer may use a combined approach of blocking the PD-1/PD-L1 signaling and targeting hypoxia-inducible factor 1α, which may help in reversing hypoxia-induced immunosuppression.
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Affiliation(s)
- S K Sureshbabu
- Chiplunkar Laboratory, Advanced Centre for Treatment, Research and Education in Cancer (ACTREC), Navi-Mumbai, India.,Homi Bhabha National Institute (HBNI), BARC Training School Complex, Anushakti Nagar, Mumbai, India
| | - D Chaukar
- Homi Bhabha National Institute (HBNI), BARC Training School Complex, Anushakti Nagar, Mumbai, India.,Tata Memorial Hospital, Parel, Mumbai, India
| | - S V Chiplunkar
- Chiplunkar Laboratory, Advanced Centre for Treatment, Research and Education in Cancer (ACTREC), Navi-Mumbai, India.,Homi Bhabha National Institute (HBNI), BARC Training School Complex, Anushakti Nagar, Mumbai, India
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12
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Chimote AA, Gawali VS, Newton HS, Wise-Draper TM, Conforti L. A Compartmentalized Reduction in Membrane-Proximal Calmodulin Reduces the Immune Surveillance Capabilities of CD8 + T Cells in Head and Neck Cancer. Front Pharmacol 2020; 11:143. [PMID: 32184726 PMCID: PMC7059094 DOI: 10.3389/fphar.2020.00143] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 02/04/2020] [Indexed: 01/28/2023] Open
Abstract
The limited ability of cytotoxic CD8+ T cells to infiltrate solid tumors and function within the tumor microenvironment presents a major roadblock to effective immunotherapy. Ion channels and Ca2+-dependent signaling events control the activity of T cells and are implicated in the failure of immune surveillance in cancer. Reduced KCa3.1 channel activity mediates the heightened inhibitory effect of adenosine on the chemotaxis of circulating T cells from head and neck squamous cell carcinoma (HNSCC) patients. Herein, we conducted experiments that elucidate the mechanisms of KCa3.1 dysfunction and impaired chemotaxis in HNSCC CD8+ T cells. The Ca2+ sensor calmodulin (CaM) controls multiple cellular functions including KCa3.1 activation. Our data showed that CaM expression is lower in HNSCC than healthy donor (HD) T cells. This reduction was due to an intrinsic decrease in the genes encoding CaM combined to the failure of HNSCC T cells to upregulate CaM upon activation. Furthermore, the reduction in CaM was confined to the plasma membrane and resulted in decreased CaM-KCa3.1 association and KCa3.1 activity (which was rescued by the delivery of CaM). IFNγ production, also Ca2+- and CaM-dependent, was instead not reduced in HNSCC T cells, which maintained intact cytoplasmic CaM and Ca2+ fluxing ability. Knockdown of CaM in HD T cells decreased KCa3.1 activity, but not IFNγ production, and reduced their chemotaxis in the presence of adenosine, thus recapitulating HNSCC T cell dysfunction. Activation of KCa3.1 with 1-EBIO restored the ability of CaM knockdown HD T cells to chemotax in the presence of adenosine. Additionally, 1-EBIO enhanced INFγ production. Our data showed a localized downregulation of membrane-proximal CaM that suppressed KCa3.1 activity in HNSCC circulating T cells and limited their ability to infiltrate adenosine-rich tumor-like microenvironments. Furthermore, they indicate that KCa3.1 activators could be used as positive CD8+ T cell modulators in cancers.
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Affiliation(s)
- Ameet A Chimote
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Vaibhavkumar S Gawali
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Hannah S Newton
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Trisha M Wise-Draper
- Division of Hematology Oncology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, United States
| | - Laura Conforti
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, United States
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13
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Berahovich R, Liu X, Zhou H, Tsadik E, Xu S, Golubovskaya V, Wu L. Hypoxia Selectively Impairs CAR-T Cells In Vitro. Cancers (Basel) 2019; 11:cancers11050602. [PMID: 31052261 PMCID: PMC6562712 DOI: 10.3390/cancers11050602] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 04/18/2019] [Accepted: 04/26/2019] [Indexed: 01/01/2023] Open
Abstract
Hypoxia is a major characteristic of the solid tumor microenvironment. To understand how chimeric antigen receptor-T cells (CAR-T cells) function in hypoxic conditions, we characterized CD19-specific and BCMA-specific human CAR-T cells generated in atmospheric (18% oxygen) and hypoxic (1% oxygen) culture for expansion, differentiation status, and CD4:CD8 ratio. CAR-T cells expanded to a much lower extent in 1% oxygen than in 18% oxygen. Hypoxic CAR-T cells also had a less differentiated phenotype and a higher CD4:CD8 ratio than atmospheric CAR-T cells. CAR-T cells were then added to antigen-positive and antigen-negative tumor cell lines at the same or lower oxygen level and characterized for cytotoxicity, cytokine and granzyme B secretion, and PD-1 upregulation. Atmospheric and hypoxic CAR-T cells exhibited comparable cytolytic activity and PD-1 upregulation; however, cytokine production and granzyme B release were greatly decreased in 1% oxygen, even when the CAR-T cells were generated in atmospheric culture. Together, these data show that at solid tumor oxygen levels, CAR-T cells are impaired in expansion, differentiation and cytokine production. These effects may contribute to the inability of CAR-T cells to eradicate solid tumors seen in many patients.
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Affiliation(s)
- Robert Berahovich
- ProMab Biotechnologies, 2600 Hilltop Drive, Richmond, CA 94806, USA.
| | - Xianghong Liu
- ProMab Biotechnologies, 2600 Hilltop Drive, Richmond, CA 94806, USA.
| | - Hua Zhou
- ProMab Biotechnologies, 2600 Hilltop Drive, Richmond, CA 94806, USA.
| | - Elias Tsadik
- ProMab Biotechnologies, 2600 Hilltop Drive, Richmond, CA 94806, USA.
| | - Shirley Xu
- ProMab Biotechnologies, 2600 Hilltop Drive, Richmond, CA 94806, USA.
| | - Vita Golubovskaya
- ProMab Biotechnologies, 2600 Hilltop Drive, Richmond, CA 94806, USA.
- Department of Medicine, University of Oklahoma, Health Sciences Center, Oklahoma City, OK 73104, USA.
| | - Lijun Wu
- ProMab Biotechnologies, 2600 Hilltop Drive, Richmond, CA 94806, USA.
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14
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Murthy A, Gerber SA, Koch CJ, Lord EM. Intratumoral Hypoxia Reduces IFN-γ-Mediated Immunity and MHC Class I Induction in a Preclinical Tumor Model. Immunohorizons 2019; 3:149-160. [PMID: 31356176 PMCID: PMC8195309 DOI: 10.4049/immunohorizons.1900017] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 04/08/2019] [Indexed: 01/08/2023] Open
Abstract
Tumor hypoxia occurs because of an increased demand for oxygen by the rapidly growing tumor cells, together with reduction in the oxygen supply due to malformed and nonfunctional tumor vasculature. The effects of tumor hypoxia on radiotherapy (RT) are well known; however, recent findings suggest it may also suppress immunotherapy, although the mechanisms governing this observation remain undetermined. Our laboratory and others have shown that IFN-γ conditions the tumor milieu and is important for the efficacy of RT. Thus, we hypothesized that hypoxia could inhibit IFN-γ–mediated antitumor responses, resulting in decreased RT efficacy. This inhibition could involve the production and/or the cellular response to IFN-γ. To test this, we used murine tumor cell lines B16F0 and Colon38. We observed that hypoxia inhibited upregulation of IFN-γ–dependent MHC class I expression by tumor cells along with the gene expression of IFN-γ–dependent chemokines CXCL9 and CXCL10, essential for immune cell infiltration. Furthermore, CD8+ T cells, an important source of IFN-γ, which mediate effector antitumor responses, had reduced ability to proliferate and generate IFN-γ under hypoxic conditions in vitro. Interestingly, reoxygenation restored the cytokine-producing capability of these cells. Studies performed in vivo using a mouse tumor model and the hypoxia marker EF5 demonstrated that RT could reverse the hypoxia within treated tumors. This study has identified a unique mechanism of hypoxia-induced immune suppression involving the downregulation of IFN-γ production and cellular responsiveness to this essential cytokine. These results suggest that therapies that target and reduce tumor hypoxia can potentially boost antitumor immune responses.
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Affiliation(s)
- Aditi Murthy
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
| | - Scott A Gerber
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642.,Department of Surgery, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642; and
| | - Cameron J Koch
- Department of Radiation Oncology, University of Pennsylvania, Philadelphia, PA 19104
| | - Edith M Lord
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642;
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15
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Zhang W, Huang H, Cai H, Tan WS. Enhanced metabolic activities for ATP production and elevated metabolic flux via pentose phosphate pathway contribute for better CIK cells expansion. Cell Prolif 2019; 52:e12594. [PMID: 30847992 PMCID: PMC6536417 DOI: 10.1111/cpr.12594] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 01/19/2019] [Accepted: 02/06/2019] [Indexed: 12/14/2022] Open
Abstract
Objective Ex vivo expansion is an effective way to produce cytokine‐induced killer (CIK) cells needed for clinical trials. Here, ex vivo expansion and metabolism characters of CIK cells in static and dynamic cultures and the relationship between cell expansion and metabolism were investigated. Materials and methods Oxygen transfer efficiency was assessed by computational fluid dynamics technique. Cell phenotype, apoptosis and of transporter expression were determined by flow cytometry and Western blotting. Metabolites and enzyme activities were assessed by biochemical methods. Results Dynamic cultures favoured better CIK cell expansion without impairing their phenotype and cytotoxicity, enhanced oxygen transfer efficiency. The glucose metabolism flux of cells in dynamic cultures was enhanced by upregulating surface glucose transporter 1 expression and phosphofructokinase activity. Moreover, pentose phosphate pathway (PPP) metabolic flux was enhanced through upregulating glucose‐6‐phosphate dehydrogenase activity. Glutaminolysis was also accelerated via boosting glutamine transporters expression, glutaminase (GLS) and glutamate dehydrogenase activities. Together with higher oxygen consumption rate and extracellular acidification rate, it was suggested that cells in dynamic cultures were in a more vigorous metabolic state for ATP production. Conclusion Dynamic cultures accelerated glucose and glutamine metabolic flux to promote ATP production, elevated glucose metabolic flux through PPP to promote biosynthesis for better cell expansion. These findings may provide the basis for ex vivo CIK cell expansion process optimization.
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Affiliation(s)
- Weiwei Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Huimin Huang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Haibo Cai
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Wen-Song Tan
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
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16
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Chimote AA, Balajthy A, Arnold MJ, Newton HS, Hajdu P, Qualtieri J, Wise-Draper T, Conforti L. A defect in KCa3.1 channel activity limits the ability of CD8 + T cells from cancer patients to infiltrate an adenosine-rich microenvironment. Sci Signal 2018; 11:11/527/eaaq1616. [PMID: 29692361 DOI: 10.1126/scisignal.aaq1616] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The limited ability of cytotoxic T cells to infiltrate solid tumors hampers immune surveillance and the efficacy of immunotherapies in cancer. Adenosine accumulates in solid tumors and inhibits tumor-specific T cells. Adenosine inhibits T cell motility through the A2A receptor (A2AR) and suppression of KCa3.1 channels. We conducted three-dimensional chemotaxis experiments to elucidate the effect of adenosine on the migration of peripheral blood CD8+ T cells from head and neck squamous cell carcinoma (HNSCC) patients. The chemotaxis of HNSCC CD8+ T cells was reduced in the presence of adenosine, and the effect was greater on HNSCC CD8+ T cells than on healthy donor (HD) CD8+ T cells. This response correlated with the inability of CD8+ T cells to infiltrate tumors. The effect of adenosine was mimicked by an A2AR agonist and prevented by an A2AR antagonist. We found no differences in A2AR expression, 3',5'-cyclic adenosine monophosphate abundance, or protein kinase A type 1 activity between HNSCC and HD CD8+ T cells. We instead detected a decrease in KCa3.1 channel activity, but not expression, in HNSCC CD8+ T cells. Activation of KCa3.1 channels by 1-EBIO restored the ability of HNSCC CD8+ T cells to chemotax in the presence of adenosine. Our data highlight the mechanism underlying the increased sensitivity of HNSCC CD8+ T cells to adenosine and the potential therapeutic benefit of KCa3.1 channel activators, which could increase infiltration of these T cells into tumors.
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Affiliation(s)
- Ameet A Chimote
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Andras Balajthy
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Michael J Arnold
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Hannah S Newton
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Peter Hajdu
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Julianne Qualtieri
- Department of Pathology, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Trisha Wise-Draper
- Division of Hematology Oncology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Laura Conforti
- Division of Nephrology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA.
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17
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Gurusamy D, Clever D, Eil R, Restifo NP. Novel "Elements" of Immune Suppression within the Tumor Microenvironment. Cancer Immunol Res 2018; 5:426-433. [PMID: 28576921 DOI: 10.1158/2326-6066.cir-17-0117] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 03/30/2017] [Accepted: 04/19/2017] [Indexed: 01/05/2023]
Abstract
Adaptive evolution has prompted immune cells to use a wide variety of inhibitory signals, many of which are usurped by tumor cells to evade immune surveillance. Although tumor immunologists often focus on genes and proteins as mediators of immune function, here we highlight two elements from the periodic table-oxygen and potassium-that suppress the immune system in previously unappreciated ways. While both are key to the maintenance of T-cell function and tissue homeostasis, they are exploited by tumors to suppress immuno-surveillance and promote metastatic spread. We discuss the temporal and spatial roles of these elements within the tumor microenvironment and explore possible therapeutic interventions for effective and promising anticancer therapies. Cancer Immunol Res; 5(6); 426-33. ©2017 AACR.
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Affiliation(s)
- Devikala Gurusamy
- Surgery Branch, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, Maryland.,Center for Cell-Based Therapy, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD
| | - David Clever
- Medical Scientist Training Program, The Ohio State University College of Medicine, Columbus, Ohio
| | - Robert Eil
- Department of Surgery, Oregon Health and Sciences University, Portland, Oregon
| | - Nicholas P Restifo
- Surgery Branch, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, Maryland. .,Center for Cell-Based Therapy, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD
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18
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Yu Q, Dong L, Li Y, Liu G. SIRT1 and HIF1α signaling in metabolism and immune responses. Cancer Lett 2018; 418:20-26. [PMID: 29306019 DOI: 10.1016/j.canlet.2017.12.035] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Revised: 12/11/2017] [Accepted: 12/22/2017] [Indexed: 12/24/2022]
Abstract
SIRT1 and HIF1α are regarded as two key metabolic sensors in cellular metabolism pathways and play vital roles in influencing immune responses. SIRT1 and HIF1α regulate immune responses in metabolism-dependent and -independent ways. Here, we summarized the recent knowledge of SIRT1 and HIF1α signaling in metabolism and immune responses. HIF1α is a direct target of SIRT1. Sometimes, SIRT1 and HIF1α cooperate or act separately to mediate immune responses. In innate immune responses, SIRT1 can regulate the glycolytic activity of myeloid-derived suppressor cells (MDSCs) and influence MDSC functional differentiation. SIRT1 can regulate monocyte function through NF-κB and PGC-1, accompanying an increased NAD+ level. The SIRT1-HIF1α axis bridges the innate immune signal to an adaptive immune response by directing cytokine production of dendritic cells in a metabolism-independent manner, promoting the differentiation of CD4+ T cells. For adaptive immune cells, SIRT1 can mediate the differentiation of inflammatory T cell subsets in a NAD+-dependent manner. HIF1α can stimulate some glycolysis-associated genes and regulate the ATP and ROS generations. In addition, SIRT1-and HIF1α-associated metabolism inhibits the activity of mTOR, thus negatively regulating the differentiation and function of Th9 cells. As immune cells are crucial in controlling immune-associated diseases, SIRT1-and HIF1α associated-metabolism is closely linked to immune-associated diseases, including infection, tumors, allergic airway inflammation, and autoimmune diseases.
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Affiliation(s)
- Qing Yu
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, Institute of Cell Biology, College of Life Sciences, Beijing Normal University, Beijing 100875 China
| | - Lin Dong
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, Institute of Cell Biology, College of Life Sciences, Beijing Normal University, Beijing 100875 China
| | - Yan Li
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, Institute of Cell Biology, College of Life Sciences, Beijing Normal University, Beijing 100875 China
| | - Gaungwei Liu
- Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, Institute of Cell Biology, College of Life Sciences, Beijing Normal University, Beijing 100875 China.
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19
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Vuillefroy de Silly R, Dietrich PY, Walker PR. Hypoxia and antitumor CD8 + T cells: An incompatible alliance? Oncoimmunology 2016; 5:e1232236. [PMID: 28123871 PMCID: PMC5214994 DOI: 10.1080/2162402x.2016.1232236] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/30/2016] [Accepted: 08/31/2016] [Indexed: 12/27/2022] Open
Abstract
T Lymphocytes face pathologically low O2 tensions within the tumor bed at which they will have to function in order to impact on the malignancy. Recent studies highlighting the importance of O2 and hypoxia-inducible factors for CD8+ T-cell function and fate must now be integrated into tumor immunology concepts if immunotherapies are to progress. Here, we discuss, reinterpret, and reconcile the many apparent contradictions in these data and we propose that O2 is a master regulator of the CD8+ T-cell response. Certain T cell functions are enhanced, others suppressed, but on balance, hypoxia is globally detrimental to the antitumor response.
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Affiliation(s)
- Romain Vuillefroy de Silly
- Geneva University Hospitals and University of Geneva, Geneva, Switzerland; Ludwig Center for Cancer Research of the University of Lausanne, Biopôle III, Epalinges, Switzerland
| | | | - Paul R Walker
- Geneva University Hospitals and University of Geneva , Geneva, Switzerland
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20
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Hypoxic stress: obstacles and opportunities for innovative immunotherapy of cancer. Oncogene 2016; 36:439-445. [PMID: 27345407 DOI: 10.1038/onc.2016.225] [Citation(s) in RCA: 253] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/03/2016] [Accepted: 05/17/2016] [Indexed: 12/11/2022]
Abstract
Tumors use several strategies to evade the host immune response, including creation of an immune-suppressive and hostile tumor environment. Tissue hypoxia due to inadequate blood supply is reported to develop very early during tumor establishment. Hypoxic stress has a strong impact on tumor cell biology. In particular, tissue hypoxia contributes to therapeutic resistance, heterogeneity and progression. It also interferes with immune plasticity, promotes the differentiation and expansion of immune-suppressive stromal cells, and remodels the metabolic landscape to support immune privilege. Therefore, tissue hypoxia has been regarded as a central factor for tumor aggressiveness and metastasis. In this regard, manipulating host-tumor interactions in the context of the hypoxic tumor microenvironment may be important in preventing or reverting malignant conversion. We will discuss how tumor microenvironment-driven transient compositional tumor heterogeneity involves hypoxic stress. Tumor hypoxia is a therapeutic concern since it can reduce the effectiveness of conventional therapies as well as cancer immunotherapy. Thus, understanding how tumor and stromal cells respond to hypoxia will allow for the design of innovative cancer therapies that can overcome these barriers. A better understanding of hypoxia-dependent mechanisms involved in the regulation of immune tolerance could lead to new strategies to enhance antitumor immunity. Therefore, discovery and validation of therapeutic targets derived from the hypoxic tumor microenvironment is of major importance. In this context, critical hypoxia-associated pathways are attractive targets for immunotherapy of cancer. In this review, we summarize current knowledge regarding the molecular mechanisms induced by tumor cell hypoxia with a special emphasis on therapeutic resistance and immune suppression. We emphasize mechanisms of manipulating hypoxic stress and its associated pathways, which may support the development of more durable and successful cancer immunotherapy approaches in the future.
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21
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Jiménez-Pérez L, Cidad P, Álvarez-Miguel I, Santos-Hipólito A, Torres-Merino R, Alonso E, de la Fuente MÁ, López-López JR, Pérez-García MT. Molecular Determinants of Kv1.3 Potassium Channels-induced Proliferation. J Biol Chem 2015; 291:3569-80. [PMID: 26655221 DOI: 10.1074/jbc.m115.678995] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Indexed: 11/06/2022] Open
Abstract
Changes in voltage-dependent potassium channels (Kv channels) associate to proliferation in many cell types, including transfected HEK293 cells. In this system Kv1.5 overexpression decreases proliferation, whereas Kv1.3 expression increases it independently of K(+) fluxes. To identify Kv1.3 domains involved in a proliferation-associated signaling mechanism(s), we constructed chimeric Kv1.3-Kv1.5 channels and point-mutant Kv1.3 channels, which were expressed as GFP- or cherry-fusion proteins. We studied their trafficking and functional expression, combining immunocytochemical and electrophysiological methods, and their impact on cell proliferation. We found that the C terminus is necessary for Kv1.3-induced proliferation. We distinguished two residues (Tyr-447 and Ser-459) whose mutation to alanine abolished proliferation. The insertion into Kv1.5 of a sequence comprising these two residues increased proliferation rate. Moreover, Kv1.3 voltage-dependent transitions from closed to open conformation induced MEK-ERK1/2-dependent Tyr-447 phosphorylation. We conclude that the mechanisms for Kv1.3-induced proliferation involve the accessibility of key docking sites at the C terminus. For one of these sites (Tyr-447) we demonstrated the contribution of MEK/ERK-dependent phosphorylation, which is regulated by voltage-induced conformational changes.
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Affiliation(s)
- Laura Jiménez-Pérez
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
| | - Pilar Cidad
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
| | - Inés Álvarez-Miguel
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
| | - Alba Santos-Hipólito
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
| | - Rebeca Torres-Merino
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
| | - Esperanza Alonso
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
| | - Miguel Ángel de la Fuente
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
| | - José Ramón López-López
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
| | - M Teresa Pérez-García
- From the Departamento de Bioquímica y Biología Molecular y Fisiología e Instituto de Biología y Genética Molecular (IBGM), Universidad de Valladolid y Consejo Superior de Investigaciones Científicas (CSIC), 47003 Valladolid, Spain
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22
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Yoon SH, Hur M, Hwang HS, Kwon HS, Sohn IS. The difference of lymphocyte subsets including regulatory T-cells in umbilical cord blood between AGA neonates and SGA neonates. Yonsei Med J 2015; 56:798-804. [PMID: 25837188 PMCID: PMC4397452 DOI: 10.3349/ymj.2015.56.3.798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
PURPOSE This study aimed to compare the regulatory T cells in cord blood of appropriate for gestational age (AGA) neonates with those of small for gestational age (SGA) neonates. MATERIALS AND METHODS Umbilical cord blood was collected upon labor in 108 healthy full-term (between 37 and 41 gestational weeks) neonates, who were born between November 2010 and April 2012. Among them, 77 samples were obtained from AGA neonates, and 31 samples were obtained from SGA neonates. Regulatory T cells and lymphocyte subsets were determined using a flow cytometer. Student's t-test for independent samples was used to compare differences between AGA and SGA neonates. RESULTS Regulatory T cells in cord blood were increased in the SGA group compared with normal controls (p=0.041). However, cytotoxic T cells in cord blood were significantly decreased in the SGA group compared with normal controls (p=0.007). CONCLUSION This is the first study to compare the distribution of lymphocyte subsets including regulatory T cells in cord blood between AGA neonates and SGA neonates.
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Affiliation(s)
- Sang Hee Yoon
- Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea
| | - Mina Hur
- Department of Laboratory Medicine, Konkuk University School of Medicine, Seoul, Korea
| | - Han Sung Hwang
- Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea
| | - Han Sung Kwon
- Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea
| | - In Sook Sohn
- Division of Maternal and Fetal Medicine, Department of Obstetrics and Gynecology, Research Institute of Medical Science, Konkuk University School of Medicine, Seoul, Korea.
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Christo SN, Diener KR, Hayball JD. The functional contribution of calcium ion flux heterogeneity in T cells. Immunol Cell Biol 2015; 93:694-704. [PMID: 25823995 DOI: 10.1038/icb.2015.34] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 02/15/2015] [Accepted: 02/16/2015] [Indexed: 12/30/2022]
Abstract
The role of intracellular calcium ion oscillations in T-cell physiology is being increasingly appreciated by studies that describe how unique temporal and spatial calcium ion signatures can control different signalling pathways. Within this review, we provide detailed mechanisms of calcium ion oscillations, and emphasise the pivotal role that calcium signalling plays in directing crucial events pertaining to T-cell functionality. We also describe methods of calcium ion quantification, and take the opportunity to discuss how a deeper understanding of calcium signalling combined with new detection and quantification methodologies can be used to better design immunotherapies targeting T-cell responses.
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Affiliation(s)
- Susan N Christo
- Experimental Therapeutics Laboratory, Sansom Institute and Hanson Institute, School of Pharmacy and Medical Science, Division of Health Sciences, University of South Australia, Adelaide, South Australia, Australia
| | - Kerrilyn R Diener
- Experimental Therapeutics Laboratory, Sansom Institute and Hanson Institute, School of Pharmacy and Medical Science, Division of Health Sciences, University of South Australia, Adelaide, South Australia, Australia.,Robinson Research Institute, School of Paediatrics and Reproductive Health, Faculty of Health Sciences, University of Adelaide, Adelaide, South Australia, Australia
| | - John D Hayball
- Experimental Therapeutics Laboratory, Sansom Institute and Hanson Institute, School of Pharmacy and Medical Science, Division of Health Sciences, University of South Australia, Adelaide, South Australia, Australia.,School of Medicine, Faculty of Health Sciences, University of Adelaide, Adelaide, South Australia, Australia
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24
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Chen K, Peng X, Fang J, Cui H, Zuo Z, Deng J, Chen Z, Geng Y, Lai W, Tang L, Yang Q. Effects of dietary selenium on histopathological changes and T cells of spleen in broilers exposed to aflatoxin B1. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2014; 11:1904-13. [PMID: 24518648 PMCID: PMC3945576 DOI: 10.3390/ijerph110201904] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 01/16/2014] [Accepted: 01/26/2014] [Indexed: 12/21/2022]
Abstract
Aflatoxin B1 (AFB1), which causes hepatocellular carcinoma and immune-suppression, is commonly found in feedstuffs. To evaluate the ability of selenium (Se) to counteract the deleterious effects of AFB1, two hundred 1-day-old male avian broilers, divided into five groups, were fed with basal diet (control group), 0.3 mg/kg AFB1 (AFB1 group), 0.3 mg/kg AFB1+0.2 mg/kg Se (+Se group I), 0.3 mg/kg AFB1+0.4 mg/kg Se (+Se group II) and 0.3 mg/kg AFB1+0.6 mg/kg Se (+Se group III), respectively. Compared with control group, the relative weight of spleen in the AFB1 group was decreased at 21 days of age. The relative weight of spleen in the three +Se groups was higher than that in the AFB1 group. By pathological observation, the major spleen lesions included congestion in red pulp and vacuoles appeared in the lymphatic nodules and periarterial lymphatic sheath in the AFB1 group. In +Se groups II and III, the incidence of major splenic lesions was decreased. The percentages of CD3+, CD3+CD4+ and CD3+CD8+ T cells in the AFB1 group were lower than those in control group from 7 to 21 days of age, while there was a marked increase in the three +Se groups compared to the AFB1 group. The results indicated that sodium selenite could improve the cellular immune function impaired by AFB1 through increasing the relative weight of spleen and percentages of splenic T cell subsets, and alleviating histopathological spleen damage.
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Affiliation(s)
- Kejie Chen
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Xi Peng
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Jing Fang
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Hengmin Cui
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Zhicai Zuo
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Junliang Deng
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Zhengli Chen
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Yi Geng
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Weimin Lai
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Li Tang
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
| | - Qingqiu Yang
- Department of Veterinary Medicine, Sichuan Agricultural University, Ya'an 625014, China.
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25
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Chimote AA, Hajdu P, Kucher V, Boiko N, Kuras Z, Szilagyi O, Yun YH, Conforti L. Selective inhibition of KCa3.1 channels mediates adenosine regulation of the motility of human T cells. THE JOURNAL OF IMMUNOLOGY 2013; 191:6273-80. [PMID: 24227782 DOI: 10.4049/jimmunol.1300702] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Adenosine, a purine nucleoside, is present at high concentrations in tumors, where it contributes to the failure of immune cells to eliminate cancer cells. The mechanisms responsible for the immunosuppressive properties of adenosine are not fully understood. We tested the hypothesis that adenosine's immunosuppressive functions in human T lymphocytes are in part mediated via modulation of ion channels. The activity of T lymphocytes relies on ion channels. KCa3.1 and Kv1.3 channels control cytokine release and, together with TRPM7, regulate T cell motility. Adenosine selectively inhibited KCa3.1, but not Kv1.3 and TRPM7, in activated human T cells. This effect of adenosine was mainly mediated by A2A receptors, as KCa3.1 inhibition was reversed by SCH58261 (selective A2A receptor antagonist), but not by MRS1754 (A2B receptor antagonist), and it was mimicked by the A2A receptor agonist CGS21680. Furthermore, it was mediated by the cAMP/protein kinase A isoform (PKAI) signaling pathway, as adenylyl-cyclase and PKAI inhibition prevented adenosine effect on KCa3.1. The functional implication of the effect of adenosine on KCa3.1 was determined by measuring T cell motility on ICAM-1 surfaces. Adenosine and CGS21680 inhibited T cell migration. Comparable effects were obtained by KCa3.1 blockade with TRAM-34. Furthermore, the effect of adenosine on cell migration was abolished by pre-exposure to TRAM-34. Additionally, adenosine suppresses IL-2 secretion via KCa3.1 inhibition. Our data indicate that adenosine inhibits KCa3.1 in human T cells via A2A receptor and PKAI, thereby resulting in decreased T cell motility and cytokine release. This mechanism is likely to contribute to decreased immune surveillance in solid tumors.
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Affiliation(s)
- Ameet A Chimote
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267
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26
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Exogenous sphingosine 1-phosphate protects murine splenocytes against hypoxia-induced injury. Lipids 2013; 49:191-202. [PMID: 24190514 DOI: 10.1007/s11745-013-3860-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Accepted: 10/21/2013] [Indexed: 01/07/2023]
Abstract
Sphingosine-1-phosphate (S1P), a biologically active pleiotropic lipid, is involved in several physiological processes especially in the area of vascular biology and immunology encompassing cell survival, angiogenesis, vascular tone, immune response etc. by interacting with specific cell surface receptors. Hypoxia, a condition common to innumerable pathologies, is known to lethally affect cell survival by throwing off balance global gene expression, redox homeostasis, bioenergetics etc. Several molecular events of cellular adaptations to hypoxia have been closely linked to stabilization of hypoxia inducible factor-1α (HIF-1α). Signalling functions of S1P in physiological events central to hypoxia-induced pathologies led us to investigate efficacy of exogenous S1P in preconditioning murine splenocytes to sustain during cellular stress associated with sub-optimal oxygen. The present study recapitulated the pro-survival benefits of exogenous S1P under normobaric hypoxia. Results indicate a direct effect of S1P supplementation on boosting cellular adaptive responses via HIF-1α stabilization and, activation of pro-survival mediators ERK and Akt. Overwhelming anti-oxidative and anti-inflammatory benefits of S1P preconditioning could also be captured in the present study, as indicated by improved redox homeostasis, reduced oxidative damage, balanced anti/pro-inflammatory cytokine profiles and temporal regulation of nitric oxide secretion and intra-cellular calcium release. Hypoxia induced cell death and the associated stress in cellular milieu in terms of oxidative damage and inflammation could be alleviated with exogenous S1P preconditioning.
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27
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Abstract
PURPOSE OF REVIEW Activation of the immune system only occurs when stimulated cells generate sufficient energy to support their growth and proliferation. Moreover, efficient HIV-1 infection requires that CD4(+) T cells meet the energy demands involved in completing the different steps of the virus life cycle. In this review, we highlight recent studies revealing the importance of nutrient fuels, nucleotide metabolism and the oxygen microenvironment in regulating HIV-1 infection, T-cell differentiation and the generation of HIV-1-specific immune responses. RECENT FINDINGS Glucose uptake via the Glut1 glucose transporter is required for efficient HIV-1 infection of CD4(+) lymphocytes. Other nutrients can also be used as sources of energy and their utilization conditions the differentiation of CD4(+) T cells to distinct effector fates. The conversion of ATP to adenosine inhibits HIV-specific effector cells and the hydrolysis of dNTPs by SAMHD1 restricts infection. Furthermore, oxygen concentration modulates metabolic status, thereby altering T-cell differentiation and potential to mediate a specific immune response. SUMMARY The availability and use of energy resources in fluctuating environments regulate T-cell function and susceptibility to HIV-1 infection. Identification of the targets coordinating the selected metabolic pathways will advance new strategic avenues for controlling HIV-1 disease progression.
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28
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Chen K, Shu G, Peng X, Fang J, Cui H, Chen J, Wang F, Chen Z, Zuo Z, Deng J, Geng Y, Lai W. Protective role of sodium selenite on histopathological lesions, decreased T-cell subsets and increased apoptosis of thymus in broilers intoxicated with aflatoxin B₁. Food Chem Toxicol 2013; 59:446-54. [PMID: 23810797 DOI: 10.1016/j.fct.2013.06.032] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 06/16/2013] [Accepted: 06/18/2013] [Indexed: 01/15/2023]
Abstract
For evaluating the ability of selenium (Se) in counteracting the adverse effects of aflatoxin B₁ (AFB₁), two hundred 1-day-old male Avian broilers, divided into five groups, were fed with basal diet (control group), 0.3 mg/kg AFB₁ (AFB₁ group), 0.3 mg/kg AFB₁+0.2 mg/kg Se (+Se group I), 0.3mg/kg AFB₁+0.4 mg/kg Se (+Se group II) and 0.3mg/kg AFB₁+0.6 mg/kg Se (+Se group III), respectively. Compared with control group, the decreased relative weight of thymus and percentages of mature thymocytes, congestion in medulla and much debris in cortex of thymus, and the increased apoptotic thymocytes were observed in AFB1 group. However, supplied dietary sodium selenite could increase the relative weight of thymus and percentages of mature thymocytes, and alleviate histopathological lesions. Compared with AFB1 group, the percentages of apoptotic thymocytes detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling method and flow cytometry method in three +Se groups were decreased, the expression of Caspase-3 and Bax, through quantitative real-time PCR and immunohistochemical method, in three +Se groups were decreased, while the expression of Bcl-2 was increased. The results indicate that sodium selenite supplied in the diet, through a mechanism of apoptosis regulation, may ameliorated AFB₁-induced lesions of thymus and accordingly improve the impaired cellular immune function.
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Affiliation(s)
- Kejie Chen
- Key Laboratory of Animal Diseases and Environmental Hazards of Sichuan Province, College of Veterinary Medicine, Sichuan Agricultural University, Ya'an, Sichuan 625014, China
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29
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McNamee EN, Korns Johnson D, Homann D, Clambey ET. Hypoxia and hypoxia-inducible factors as regulators of T cell development, differentiation, and function. Immunol Res 2013; 55:58-70. [PMID: 22961658 DOI: 10.1007/s12026-012-8349-8] [Citation(s) in RCA: 164] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Oxygen is a molecule that is central to cellular respiration and viability, yet there are multiple physiologic and pathological contexts in which cells experience conditions of insufficient oxygen availability, a state known as hypoxia. Given the metabolic challenges of a low oxygen environment, hypoxia elicits a range of adaptive responses at the cellular, tissue, and systemic level to promote continued survival and function. Within this context, T lymphocytes are a highly migratory cell type of the adaptive immune system that frequently encounters a wide range of oxygen tensions in both health and disease. It is now clear that oxygen availability regulates T cell differentiation and function, a response orchestrated in large part by the hypoxia-inducible factor transcription factors. Here, we discuss the physiologic scope of hypoxia and hypoxic signaling, the contribution of these pathways in regulating T cell biology, and current gaps in our understanding. Finally, we discuss how emerging therapies that modulate the hypoxic response may offer new modalities to alter T cell function and the outcome of acute and chronic pathologies.
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Affiliation(s)
- Eóin N McNamee
- Mucosal Inflammation Program, Department of Anesthesiology, School of Medicine, University of Colorado Denver, Aurora, CO 80045, USA
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30
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Affiliation(s)
- Leonore A Herzenberg
- Genetics Department, Stanford University School of Medicine, Stanford, California 94305, USA
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31
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Zhao N, Dong Q, Du LL, Fu XX, Du YM, Liao YH. Potent suppression of Kv1.3 potassium channel and IL-2 secretion by diphenyl phosphine oxide-1 in human T cells. PLoS One 2013; 8:e64629. [PMID: 23717641 PMCID: PMC3661503 DOI: 10.1371/journal.pone.0064629] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 04/16/2013] [Indexed: 11/18/2022] Open
Abstract
Diphenyl phosphine oxide-1 (DPO-1) is a potent Kv1.5 channel inhibitor that has therapeutic potential for the treatment of atrial fibrillation. Many other Kv1.5 channel blockers also potently inhibit the Kv1.3 channel, but whether DPO-1 blocks Kv1.3 channels has not been investigated. The Kv1.3 channel is highly expressed in activated T cells, which is considered a favorable target for immunomodulation. Accordingly, we hypothesized that DPO-1 may exert immunosuppressive and anti-inflammatory effects by inhibiting Kv1.3 channel activity. In this study, DPO-1 blocked Kv1.3 current in a voltage-dependent and concentration-dependent manner, with IC₅₀ values of 2.58 µM in Jurkat cells and 3.11 µM in human peripheral blood T cells. DPO-1 also accelerated the inactivation rate and negatively shifted steady-state inactivation. Moreover, DPO-1 at 3 µM had no apparent effect on the Ca²⁺ activated potassium channel (K(Ca)) current in both Jurkat cells and human peripheral blood T cells. In Jurkat cells, pre-treatment with DPO-1 for 24 h decreased Kv1.3 current density, and protein expression by 48±6% and 60±9%, at 3 and 10 µM, respectively (both p<0.05). In addition, Ca²⁺ influx to Ca²⁺-depleted cells was blunted and IL-2 production was also reduced in activated Jurkat cells. IL-2 secretion was also inhibited by the Kv1.3 inhibitors margatoxin and charybdotoxin. Our results demonstrate for the first time that that DPO-1, at clinically relevant concentrations, blocks Kv1.3 channels, decreases Kv1.3 channel expression and suppresses IL-2 secretion. Therefore, DPO-1 may be a useful treatment strategy for immunologic disorders.
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Affiliation(s)
- Ning Zhao
- Research Center of Ion Channelopathy, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Qian Dong
- Research Center of Ion Channelopathy, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Li-Li Du
- Research Center of Ion Channelopathy, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Xiao-Xing Fu
- Research Center of Ion Channelopathy, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Yi-Mei Du
- Research Center of Ion Channelopathy, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
- * E-mail: (Y-MD); (Y-HL)
| | - Yu-Hua Liao
- Research Center of Ion Channelopathy, Institute of Cardiovascular Diseases, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
- * E-mail: (Y-MD); (Y-HL)
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Kuras Z, Yun YH, Chimote AA, Neumeier L, Conforti L. KCa3.1 and TRPM7 channels at the uropod regulate migration of activated human T cells. PLoS One 2012; 7:e43859. [PMID: 22952790 PMCID: PMC3428288 DOI: 10.1371/journal.pone.0043859] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Accepted: 07/30/2012] [Indexed: 11/18/2022] Open
Abstract
The migration of T lymphocytes is an essential part of the adaptive immune response as T cells circulate around the body to carry out immune surveillance. During the migration process T cells polarize, forming a leading edge at the cell front and a uropod at the cell rear. Our interest was in studying the involvement of ion channels in the migration of activated human T lymphocytes as they modulate intracellular Ca(2+) levels. Ca(2+) is a key regulator of cellular motility. To this purpose, we created protein surfaces made of the bio-polymer PNMP and coated with ICAM-1, ligand of LFA-1. The LFA-1 and ICAM-1 interaction facilitates T cell movement from blood into tissues and it is critical in immune surveillance and inflammation. Activated human T lymphocytes polarized and migrated on ICAM-1 surfaces by random walk with a mean velocity of ∼6 µm/min. Confocal microscopy indicated that Kv1.3, CRAC, and TRPM4 channels positioned in the leading-edge, whereas KCa3.1 and TRPM7 channels accumulated in the uropod. The localization of KCa3.1 and TRPM7 at the uropod was associated with oscillations in intracellular Ca(2+) levels that we measured in this cell compartment. Further studies with blockers against Kv1.3 (ShK), KCa3.1 (TRAM-34), CRAC (SKF-96365), TRPM7 (2-APB), and TRPM4 (glibenclamide) indicated that blockade of KCa3.1 and TRPM7, and not Kv1.3, CRAC or TRPM4, inhibits the T cell migration. The involvement of TRPM7 in cell migration was confirmed with siRNAs against TRPM7. Downregulation of TRPM7 significantly reduced the number of migrating T cells and the mean velocity of the migrating T cells. These results indicate that KCa3.1 and TRPM7 selectively localize at the uropod of migrating T lymphocytes and are key components of the T cell migration machinery.
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Affiliation(s)
- Zerrin Kuras
- Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Yeo-Heung Yun
- Department of Bioengineering, North Carolina Agricultural and Technical State University, Greensboro, North Carolina, United States of America
| | - Ameet A. Chimote
- Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Lisa Neumeier
- Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Laura Conforti
- Department of Molecular and Cellular Physiology, University of Cincinnati, Cincinnati, Ohio, United States of America
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Kuras Z, Kucher V, Gordon SM, Neumeier L, Chimote AA, Filipovich AH, Conforti L. Modulation of Kv1.3 channels by protein kinase A I in T lymphocytes is mediated by the disc large 1-tyrosine kinase Lck complex. Am J Physiol Cell Physiol 2012; 302:C1504-12. [PMID: 22378744 DOI: 10.1152/ajpcell.00263.2011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The cAMP/PKA signaling system constitutes an inhibitory pathway in T cells and, although its biochemistry has been thoroughly investigated, its possible effects on ion channels are still not fully understood. K(V)1.3 channels play an important role in T-cell activation, and their inhibition suppresses T-cell function. It has been reported that PKA modulates K(V)1.3 activity. Two PKA isoforms are expressed in human T cells: PKAI and PKAII. PKAI has been shown to inhibit T-cell activation via suppression of the tyrosine kinase Lck. The aim of this study was to determine the PKA isoform modulating K(V)1.3 and the signaling pathway underneath. 8-Bromoadenosine 3',5'-cyclic monophosphate (8-BrcAMP), a nonselective activator of PKA, inhibited K(V)1.3 currents both in primary human T and in Jurkat cells. This inhibition was prevented by the PKA blocker PKI(6-22). Selective knockdown of PKAI, but not PKAII, with siRNAs abolished the response to 8-BrcAMP. Additional studies were performed to determine the signaling pathway mediating PKAI effect on K(V)1.3. Overexpression of a constitutively active mutant of Lck reduced the response of K(V)1.3 to 8-Br-cAMP. Moreover, knockdown of the scaffolding protein disc large 1 (Dlg1), which binds K(V)1.3 to Lck, abolished PKA modulation of K(V)1.3 channels. Immunohistochemistry studies showed that PKAI, but not PKAII, colocalizes with K(V)1.3 and Dlg1 indicating a close proximity between these proteins. These results indicate that PKAI selectively regulates K(V)1.3 channels in human T lymphocytes. This effect is mediated by Lck and Dlg1. We thus propose that the K(V)1.3/Dlg1/Lck complex is part of the membrane pathway that cAMP utilizes to regulate T-cell function.
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Affiliation(s)
- Zerrin Kuras
- Department of Internal Medicine, 231 Albert Sabin Way, University of Cincinnati, Cincinnati, OH 45267-0585, USA
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34
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Abstract
Cell cycle entry is commonly considered to positively regulate HIV-1 infection of CD4 T cells, raising the question as to how quiescent lymphocytes, representing a large portion of the viral reservoir, are infected in vivo. Factors such as the homeostatic cytokine IL-7 have been shown to render quiescent T cells permissive to HIV-1 infection, presumably by transiently stimulating their entry into the cell cycle. However, we show here that at physiological oxygen (O(2)) levels (2-5% O(2) tension in lymphoid organs), IL-7 stimulation generates an environment permissive to HIV-1 infection, despite a significantly attenuated level of cell cycle entry. We identify the IL-7-induced increase in Glut1 expression, resulting in augmented glucose uptake, as a key factor in rendering these T lymphocytes susceptible to HIV-1 infection. HIV-1 infection of human T cells is abrogated either by impairment of Glut1 signal transduction or by siRNA-mediated Glut1 down-regulation. Consistent with this, we show that the susceptibility of human thymocyte subsets to HIV-1 infection correlates with Glut1 expression; single-round infection is markedly higher in the Glut1-expressing double-positive thymocyte population than in any of the Glut1-negative subsets. Thus, our studies reveal the Glut1-mediated metabolic pathway as a critical regulator of HIV-1 infection in human CD4 T cells and thymocytes.
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35
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Martin GV, Yun Y, Conforti L. Modulation of T cell activation by localized K⁺ accumulation at the immunological synapse--a mathematical model. J Theor Biol 2012; 300:173-82. [PMID: 22285786 DOI: 10.1016/j.jtbi.2012.01.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2011] [Revised: 12/21/2011] [Accepted: 01/11/2012] [Indexed: 01/06/2023]
Abstract
The response of T cells to antigens (T cell activation) is marked by an increase in intracellular Ca²⁺ levels. Voltage-gated and Ca²⁺-dependent K⁺ channels control the membrane potential of human T cells and regulate Ca²⁺ influx. This regulation is dependent on proper accumulation of K⁺ channels at the immunological synapse (IS) a signaling zone that forms between a T cell and antigen presenting cell. It is believed that the IS provides a site for regulation of the activation response and that K⁺ channel inhibition occurs at the IS, but the underlying mechanisms are unknown. A mathematical model was developed to test whether K⁺ efflux through K⁺ channels leads to an accumulation of K⁺ in the IS cleft, ultimately reducing K⁺ channel function and intracellular Ca²⁺ concentration ([Ca²⁺](i)). Simulations were conducted in models of resting and activated T cell subsets, which express different levels of K⁺ channels, by varying the K⁺ diffusion constant and the spatial localization of K⁺ channels at the IS. K⁺ accumulation in the IS cleft was calculated to increase K⁺ concentration ([K⁺]) from its normal value of 5.0 mM to 5.2-10.0 mM. Including K⁺ accumulation in the model of the IS reduced calculated K⁺ current by 1-12% and consequently, reduced calculated [Ca²⁺](i) by 1-28%. Significant reductions in K⁺ current and [Ca²⁺](i) only occurred in activated T cell simulations when most K⁺ channels were centrally clustered at the IS. The results presented show that the localization of K⁺ channels at the IS can produce a rise in [K⁺] in the IS cleft and lead to a substantial decrease in K⁺ currents and [Ca²⁺](i) in activated T cells thus providing a feedback inhibitory mechanism during T cell activation.
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Affiliation(s)
- Geoffrey V Martin
- Department of Internal Medicine, 231 A. Sabin Way, Division of Nephrology, University of Cincinnati, Cincinnati, OH 45267-0585, USA
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36
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Chimote AA, Kuras Z, Conforti L. Disruption of kv1.3 channel forward vesicular trafficking by hypoxia in human T lymphocytes. J Biol Chem 2011; 287:2055-67. [PMID: 22134923 DOI: 10.1074/jbc.m111.274209] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Hypoxia in solid tumors contributes to decreased immunosurveillance via down-regulation of Kv1.3 channels in T lymphocytes and associated T cell function inhibition. However, the mechanisms responsible for Kv1.3 down-regulation are not understood. We hypothesized that chronic hypoxia reduces Kv1.3 surface expression via alterations in membrane trafficking. Chronic hypoxia decreased Kv1.3 surface expression and current density in Jurkat T cells. Inhibition of either protein synthesis or degradation and endocytosis did not prevent this effect. Instead, blockade of clathrin-coated vesicle formation and forward trafficking prevented the Kv1.3 surface expression decrease in hypoxia. Confocal microscopy revealed an increased retention of Kv1.3 in the trans-Golgi during hypoxia. Expression of adaptor protein-1 (AP1), responsible for clathrin-coated vesicle formation at the trans-Golgi, was selectively down-regulated by hypoxia. Furthermore, AP1 down-regulation increased Kv1.3 retention in the trans-Golgi and reduced Kv1.3 currents. Our results indicate that hypoxia disrupts AP1/clathrin-mediated forward trafficking of Kv1.3 from the trans-Golgi to the plasma membrane thus contributing to decreased Kv1.3 surface expression in T lymphocytes.
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Affiliation(s)
- Ameet A Chimote
- Department of Internal Medicine, University of Cincinnati, Cincinnati, Ohio 45267, USA
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When Cells Suffocate: Autophagy in Cancer and Immune Cells under Low Oxygen. Int J Cell Biol 2011; 2011:470597. [PMID: 22190938 PMCID: PMC3235465 DOI: 10.1155/2011/470597] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 08/14/2011] [Indexed: 11/18/2022] Open
Abstract
Hypoxia is a signature feature of growing tumors. This cellular state creates an inhospitable condition that impedes the growth and function of all cells within the immediate and surrounding tumor microenvironment. To adapt to hypoxia, cells activate autophagy and undergo a metabolic shift increasing the cellular dependency on anaerobic metabolism. Autophagy upregulation in cancer cells liberates nutrients, decreases the buildup of reactive oxygen species, and aids in the clearance of misfolded proteins. Together, these features impart a survival advantage for cancer cells in the tumor microenvironment. This observation has led to intense research efforts focused on developing autophagy-modulating drugs for cancer patient treatment. However, other cells that infiltrate the tumor environment such as immune cells also encounter hypoxia likely resulting in hypoxia-induced autophagy. In light of the fact that autophagy is crucial for immune cell proliferation as well as their effector functions such as antigen presentation and T cell-mediated killing of tumor cells, anticancer treatment strategies based on autophagy modulation will need to consider the impact of autophagy on the immune system.
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Ohta A, Diwanji R, Kini R, Subramanian M, Ohta A, Sitkovsky M. In vivo T cell activation in lymphoid tissues is inhibited in the oxygen-poor microenvironment. Front Immunol 2011; 2:27. [PMID: 22566817 PMCID: PMC3342240 DOI: 10.3389/fimmu.2011.00027] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2011] [Accepted: 06/21/2011] [Indexed: 11/13/2022] Open
Abstract
Activation of immune cells is under control of immunological and physiological regulatory mechanisms to ensure adequate destruction of pathogens with the minimum collateral damage to “innocent” bystander cells. The concept of physiological negative regulation of immune response has been advocated based on the finding of the critical immunoregulatory role of extracellular adenosine. Local tissue oxygen tension was proposed to function as one of such physiological regulatory mechanisms of immune responses. In the current study, we utilized in vivo marker of local tissue hypoxia pimonidazole hydrochloride (Hypoxyprobe-1) in the flowcytometric analysis of oxygen levels to which lymphocytes are exposed in vivo. The level of exposure to hypoxia in vivo was low in B cells and the levels increased in the following order: T cells < NKT cells < NK cells. The thymus was more hypoxic than the spleen and lymph nodes, suggesting the variation in the degree of oxygenation among lymphoid organs and cell types in normal mice. Based on in vitro studies, tissue hypoxia has been assumed to be suppressive to T cell activation in vivo, but there was no direct evidence demonstrating that T cells exposed to hypoxic environment in vivo are less activated. We tested whether the state of activation of T cells in vivo changes due to their exposure to hypoxic tissue microenvironments. The parallel analysis of more hypoxic and less hypoxic T cells in the same mouse revealed that the degree of T cell activation was significantly stronger in better-oxygenated T cells. These observations suggest that the extent of T cell activation in vivo is dependent on their localization and is decreased in environment with low oxygen tension.
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Affiliation(s)
- Akio Ohta
- New England Inflammation and Tissue Protection Institute, Northeastern University Boston, MA, USA.
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Muthana M, Multhoff G, Pockley AG. Tumour infiltrating host cells and their significance for hyperthermia. Int J Hyperthermia 2010; 26:247-55. [PMID: 20388022 DOI: 10.3109/02656730903413375] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Much information can be gained by investigating the consequences of hyperthermia on individual cell populations in vitro, however the precise effects of such a therapeutic modality in vivo depend on the tumour microenvironment and the cellular composition therein. Although the direct cytotoxic effects of hyperthermia on tumour tissue can lead to an immediate reduction in tumour volume, long-term benefits to local and distal tumour recurrence will very much depend on the induction of immunity and the capacity of effector cells to traffic to tumours and elicit their cytotoxic functions. The immunological sequelae to hyperthermia are even more important in those instances when large tumour volumes preclude the delivery of appropriate thermal damage. The development of protective anti-tumour immunity requires a plethora of interactions and responses, the vast majority of which can be influenced by temperatures that are consistent with fever-like temperatures (39 degrees -40 degrees C), as well as hyperthermia treatment (<41 degrees C). This article reviews current knowledge relating to the effects of hyperthermia treatment on aspects of the induction and manifestation of immunological responses that are most pertinent to the development and maintenance of protective anti-tumour immunity.
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Affiliation(s)
- Munitta Muthana
- Department of Infection and Immunity, The Medical School, University of Sheffield, Sheffield, UK
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Varga Z, Hajdu P, Panyi G. Ion channels in T lymphocytes: An update on facts, mechanisms and therapeutic targeting in autoimmune diseases. Immunol Lett 2010; 130:19-25. [DOI: 10.1016/j.imlet.2009.12.015] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2009] [Revised: 12/08/2009] [Accepted: 12/10/2009] [Indexed: 12/31/2022]
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Dziurla R, Gaber T, Fangradt M, Hahne M, Tripmacher R, Kolar P, Spies CM, Burmester GR, Buttgereit F. Effects of hypoxia and/or lack of glucose on cellular energy metabolism and cytokine production in stimulated human CD4+ T lymphocytes. Immunol Lett 2010; 131:97-105. [PMID: 20206208 DOI: 10.1016/j.imlet.2010.02.008] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2009] [Revised: 02/23/2010] [Accepted: 02/24/2010] [Indexed: 02/05/2023]
Abstract
Oxidative phosphorylation and/or glycolysis provide energy, mainly in the form of ATP, which ensures proper functioning of immune cells such as CD4(+) T lymphocytes. However, the main substrates, namely oxygen and glucose, are known to remain for a relatively short time in the inflamed tissue and in other clinical situations where immune cells need to function properly. Therefore, we examined the effect of hypoxia and/or lack of glucose on cellular energy metabolism and on cytokine secretion in stimulated human CD4(+) T lymphocytes. Human CD4(+) T cells were MACS-isolated using peripheral blood obtained from healthy donors. Stimulated cells were incubated in medium with or without glucose for 6h in a sealed chamber which led to cumulative hypoxia. During this incubation period, (i) oxygen saturation was measured continuously using a Clark-type electrode, and (ii) samples were taken at different time points in order to quantify for each the viability of cells, intracellular reactive oxygen species (iROS), ATP levels, glycolytic enzyme activity, mRNA expression of hexokinase-1 and superoxide dismutase-1, and concentrations of several different cytokines. Stimulated CD4(+) T cells which were incubated under normoxic conditions served as controls. Under hypoxic conditions, lack of glucose exerted a biphasic effect on cellular oxygen consumption: initially higher but later lower respiration rates were measured when compared to conditions where glucose was available. Lack of glucose strongly increased the number of dead cells and the formation of iROS under normoxia but not under hypoxia. Under both normoxic and hypoxic conditions, intracellular ATP levels remained almost unchanged during the incubation period if glucose was present, but decreased significantly in the absence of glucose, despite the enhanced glycolytic enzyme activity. Measurements of stimulated cytokine production demonstrated (i) that cumulative hypoxia stimulates especially the secretion of IL-1beta, IL-10 and IL-8, and (ii) that lack of glucose results in lower cytokine concentrations. We demonstrate that CD4(+) T cells are highly adaptive in bioenergetic terms which ensure their proper function under extreme conditions of glucose and/or oxygen availability as found under physiological and pathophysiological conditions. Hypoxia seems to facilitate inflammatory reactions and angiogenesis.
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Affiliation(s)
- R Dziurla
- Department of Rheumatology and Clinical Immunology, Charité University Hospital, Charitéplatz 1, Berlin, Germany.
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Nicolaou SA, Neumeier L, Takimoto K, Lee SM, Duncan HJ, Kant SK, Mongey AB, Filipovich AH, Conforti L. Differential calcium signaling and Kv1.3 trafficking to the immunological synapse in systemic lupus erythematosus. Cell Calcium 2009; 47:19-28. [PMID: 19959227 DOI: 10.1016/j.ceca.2009.11.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 10/27/2009] [Accepted: 11/02/2009] [Indexed: 11/24/2022]
Abstract
Systemic lupus erythematosus (SLE) T cells exhibit several activation signaling anomalies including defective Ca(2+) response and increased NF-AT nuclear translocation. The duration of the Ca(2+) signal is critical in the activation of specific transcription factors and a sustained Ca(2+) response activates NF-AT. Yet, the distribution of Ca(2+) responses in SLE T cells is not known. Furthermore, the mechanisms responsible for Ca(2+) alterations are not fully understood. Kv1.3 channels control Ca(2+) homeostasis in T cells. We reported a defect in Kv1.3 trafficking to the immunological synapse (IS) of SLE T cells that might contribute to the Ca(2+) defect. The present study compares single T cell quantitative Ca(2+) responses upon formation of the IS in SLE, normal, and rheumatoid arthritis (RA) donors. Also, we correlated cytosolic Ca(2+) concentrations and Kv1.3 trafficking in the IS by two-photon microscopy. We found that sustained [Ca(2+)](i) elevations constitute the predominant response to antigen stimulation of SLE T cells. This defect is selective to SLE as it was not observed in RA T cells. Further, we observed that in normal T cells termination of Ca(2+) influx is accompanied by Kv1.3 permanence in the IS, while Kv1.3 premature exit from the IS correlates with sustained Ca(2+) responses in SLE T cells. Thus, we propose that Kv1.3 trafficking abnormalities contribute to the altered distribution in Ca(2+) signaling in SLE T cells. Overall these defects may explain in part the T cell hyperactivity and dysfunction documented in SLE patients.
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Affiliation(s)
- Stella A Nicolaou
- Department of Internal Medicine, University of Cincinnati, OH 45267, USA
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Nicolaou SA, Neumeier L, Steckly A, Kucher V, Takimoto K, Conforti L. Localization of Kv1.3 channels in the immunological synapse modulates the calcium response to antigen stimulation in T lymphocytes. THE JOURNAL OF IMMUNOLOGY 2009; 183:6296-302. [PMID: 19841189 DOI: 10.4049/jimmunol.0900613] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The immunological synapse (IS), a highly organized structure that forms at the point of contact between a T cell and an APC, is essential for the proper development of signaling events, including the Ca(2+) response. Kv1.3 channels control Ca(2+) homeostasis in human T cells and move into the IS upon Ag presentation. However, the process involved in channel accumulation in the IS and the functional implications of this localization are not yet known. Here we define the movement of Kv1.3 into the IS and study whether Kv1.3 localization into the IS influences Ca(2+) signaling in Jurkat T cells. Crosslinking of the channel protein with an extracellular Ab limits Kv1.3 mobility and accumulation at the IS. Moreover, Kv1.3 recruitment to the IS does not involve the transport of newly synthesized channels and it does not occur through recycling of membrane channels. Kv1.3 localization in the IS modulates the Ca(2+) response. Blockade of Kv1.3 movement into the IS by crosslinking significantly increases the amplitude of the Ca(2+) response triggered by anti-CD3/anti-CD28-coated beads, which induce the formation of the IS. On the contrary, the Ca(2+) response induced by TCR stimulation without the formation of the IS with soluble anti-CD3/anti-CD28 Abs is unaltered. The results presented herein indicate that, upon Ag presentation, membrane-incorporated Kv1.3 channels move along the plasma membrane to localize in the IS. This localization is important to control the amplitude of the Ca(2+) response, and disruption of this process can account for alterations of downstream Ca(2+)-dependent signaling events.
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Affiliation(s)
- Stella A Nicolaou
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
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Abstract
For more than 25 years, it has been widely appreciated that Ca2+ influx is essential to trigger T-lymphocyte activation. Patch clamp analysis, molecular identification, and functional studies using blockers and genetic manipulation have shown that a unique contingent of ion channels orchestrates the initiation, intensity, and duration of the Ca2+ signal. Five distinct types of ion channels--Kv1.3, KCa3.1, Orai1+ stromal interacting molecule 1 (STIM1) [Ca2+-release activating Ca2+ (CRAC) channel], TRPM7, and Cl(swell)--comprise a network that performs functions vital for ongoing cellular homeostasis and for T-cell activation, offering potential targets for immunomodulation. Most recently, the roles of STIM1 and Orai1 have been revealed in triggering and forming the CRAC channel following T-cell receptor engagement. Kv1.3, KCa3.1, STIM1, and Orai1 have been found to cluster at the immunological synapse following contact with an antigen-presenting cell; we discuss how channels at the synapse might function to modulate local signaling. Immuno-imaging approaches are beginning to shed light on ion channel function in vivo. Importantly, the expression pattern of Ca2+ and K+ channels and hence the functional network can adapt depending upon the state of differentiation and activation, and this allows for different stages of an immune response to be targeted specifically.
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Affiliation(s)
- Michael D Cahalan
- Department of Physiology and Biophysics, and the Institute for Immunology, University of California, Irvine, Irvine, CA 92697-4561, USA.
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Roman J, Rangasamy T, Guo J, Sugunan S, Meednu N, Packirisamy G, Shimoda LA, Golding A, Semenza G, Georas SN. T-cell activation under hypoxic conditions enhances IFN-gamma secretion. Am J Respir Cell Mol Biol 2009; 42:123-8. [PMID: 19372249 DOI: 10.1165/rcmb.2008-0139oc] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Secondary lymphoid organs and peripheral tissues are characterized by hypoxic microenvironments, both in the steady state and during inflammation. Although hypoxia regulates T-cell metabolism and survival, very little is known about whether or how hypoxia influences T-cell activation. We stimulated mouse CD4(+) T cells in vitro with antibodies directed against the T-cell receptor (CD3) and CD28 under normoxic (20% O(2)) and hypoxic (1% O(2)) conditions. Here we report that stimulation under hypoxic conditions augments the secretion of effector CD4(+) T-cell cytokines, especially IFN-gamma. The enhancing effects of hypoxia on IFN-gamma secretion were independent of mouse strain, and were also unaffected using CD4(+) T cells from mice lacking one copy of the gene encoding hypoxia-inducible factor-1alpha. Using T cells from IFN-gamma receptor-deficient mice and promoter reporter studies in transiently transfected Jurkat T cells, we found that the enhancing effects of hypoxia on IFN-gamma expression were not due to effects on IFN-gamma consumption or proximal promoter activity. In contrast, deletion of the transcription factor, nuclear erythroid 2 p45-related factor 2 attenuated the enhancing effect of hypoxia on IFN-gamma secretion and other cytokines. We conclude that hypoxia is a previously underappreciated modulator of effector cytokine secretion in CD4(+) T cells.
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Affiliation(s)
- Jessica Roman
- University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642-8692, USA
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Ben-Shoshan J, Afek A, Maysel-Auslender S, Barzelay A, Rubinstein A, Keren G, George J. HIF-1alpha overexpression and experimental murine atherosclerosis. Arterioscler Thromb Vasc Biol 2009; 29:665-70. [PMID: 19251587 DOI: 10.1161/atvbaha.108.183319] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Lymphocytes play an important role in the progression of atherosclerosis. Recently, hypoxia inducible factor-1 (HIF-1) was found to attenuate inflammation by regulating T cell activation and cytokine production. We studied the effects of overexpression of HIF-1alpha in ApoE knockout murine lymphocytes, on experimental atherosclerosis. METHODS AND RESULTS ApoE-/- mice were submitted to intravenous hydrodynamic injection of empty plasmid or HIF-1alphaP564A (HIF-1alpha mutated stabilized construct). Robust expression of HIF-1alpha was evident in spleen cells of recipient animals. Increased expression of IL-10 as well as decreased expression of IFN-gamma was measured in splenocytes of HIF-1alpha-treated mice by RT-PCR. One week postinjection, antibody array analysis revealed a pattern consistent with a T helper 1 to T helper 2 shift. On sacrifice, assessment of aortic sinus lesions revealed a significant reduction in plaque size in HIF-1alpha injected mice. A reduced expression of IFN-gamma was evident in CD4+ spleen-derived lymphocytes and aortas of HIF-1alpha-injected mice. CONCLUSIONS HIF-1alpha expression in mouse lymphocytes is associated with a reduced IFN-gamma expression and attenuation of experimental atherosclerosis.
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Affiliation(s)
- Jeremy Ben-Shoshan
- Department of Cardiology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
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Guo J, Lu W, Shimoda LA, Semenza GL, Georas SN. Enhanced interferon-gamma gene expression in T Cells and reduced ovalbumin-dependent lung eosinophilia in hypoxia-inducible factor-1-alpha-deficient mice. Int Arch Allergy Immunol 2009; 149:98-102. [PMID: 19127065 DOI: 10.1159/000189191] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2008] [Accepted: 09/03/2008] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND There is growing evidence that hypoxia-inducible transcription factors are involved in the pathophysiology of asthma. Hypoxia-inducible factor-1alpha (HIF-1alpha) in particular controls the expression of many hypoxia regulated genes, but whether HIF-1alpha directly contributes to allergen-driven immune responses is not known. METHODS Partially HIF-1alpha-deficient mice (HIF-1alpha(+/-)) or wild-type littermate controls were used in all experiments. Spleen CD4+ T cells were stimulated with anti-CD3 plus anti-CD28 antibodies and cytokine secretion was measured in vitro. Mice were sensitized by intraperitoneal injection of ovalbumin (Ova) plus alum, and then challenged by intranasal Ova followed by bronchoalveolar lavage (BAL) and isolation of spleen cells. BAL cells were counted and the differential determined using cytospin, and splenocytes were incubated with Ova to measure recall cytokine production. RESULTS Interferon-gamma secretion was significantly higher in anti-CD3 plus anti-CD28 stimulated CD4+ T cells obtained from HIF-1alpha(+/-) mice compared to wild-type controls. HIF-1alpha(+/-) mice were protected from lung eosinophilia 72 h after allergen challenge, in association with enhanced secretion of interferon-gamma in recall responses of splenocytes. CONCLUSIONS HIF-1alpha contributes to allergic immune responses and lung eosinophilia in a mouse model of asthma.
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Affiliation(s)
- Jia Guo
- Division of Pulmonary and Critical Care, University of Rochester Medical Center, Rochester 14642, NY, USA
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Ben-Shoshan J, Maysel-Auslender S, Mor A, Keren G, George J. Hypoxia controls CD4+CD25+ regulatory T-cell homeostasis via hypoxia-inducible factor-1alpha. Eur J Immunol 2008; 38:2412-8. [PMID: 18792019 DOI: 10.1002/eji.200838318] [Citation(s) in RCA: 202] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Recent data suggest that hypoxia and its principal molecular signature HIF-1 (hypoxia-inducing factor-1) may tune down inflammation by dictating anti-inflammatory programs. We tested the effects of hypoxia and HIF-1alpha on the homeostasis of naturally occurring regulatory T cells (Treg) and their transcriptional activator Foxp3. Hypoxia induced a time-dependent increase in HIF-1alpha in mouse and human T cells. Hypoxia upregulated the expression of Foxp3 in Jurkat T cells, human and murine mononuclear cells. The effects of hypoxia on Foxp3 expression were HIF-1alpha-dependent as they were abolished upon transfection with short-interfering RNAs for HIF-1alpha and promoted by HIF-1alpha overexpression. Hypoxia increased the potency of Treg, as hypoxic CD4(+)CD25(+) lymphocytes were more effective than normoxic cells in suppressing the proliferation of CD4(+)CD25(-) effectors. In vivo expression of HIF-1alpha achieved by hydrodynamic injection of the respective naked DNA similarly induced an increase in Foxp3 expression and an increase in the number of functionally active Foxp3(+)CD4(+)CD25(+) Treg. Thus, hypoxia dictates an anti-inflammatory program by driving expression of HIF-1alpha that acts to increase the number and suppressive properties of naturally occurring CD4(+)CD25(+) Treg.
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Affiliation(s)
- Jeremy Ben-Shoshan
- The Department of Cardiology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
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Nicolaou SA, Szigligeti P, Neumeier L, Lee SM, Duncan HJ, Kant SK, Mongey AB, Filipovich AH, Conforti L. Altered dynamics of Kv1.3 channel compartmentalization in the immunological synapse in systemic lupus erythematosus. THE JOURNAL OF IMMUNOLOGY 2007; 179:346-56. [PMID: 17579055 PMCID: PMC2453311 DOI: 10.4049/jimmunol.179.1.346] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Aberrant T cell responses during T cell activation and immunological synapse (IS) formation have been described in systemic lupus erythematosus (SLE). Kv1.3 potassium channels are expressed in T cells where they compartmentalize at the IS and play a key role in T cell activation by modulating Ca(2+) influx. Although Kv1.3 channels have such an important role in T cell function, their potential involvement in the etiology and progression of SLE remains unknown. This study compares the K channel phenotype and the dynamics of Kv1.3 compartmentalization in the IS of normal and SLE human T cells. IS formation was induced by 1-30 min exposure to either anti-CD3/CD28 Ab-coated beads or EBV-infected B cells. We found that although the level of Kv1.3 channel expression and their activity in SLE T cells is similar to normal resting T cells, the kinetics of Kv1.3 compartmentalization in the IS are markedly different. In healthy resting T cells, Kv1.3 channels are progressively recruited and maintained in the IS for at least 30 min from synapse formation. In contrast, SLE, but not rheumatoid arthritis, T cells show faster kinetics with maximum Kv1.3 recruitment at 1 min and movement out of the IS by 15 min after activation. These kinetics resemble preactivated healthy T cells, but the K channel phenotype of SLE T cells is identical to resting T cells, where Kv1.3 constitutes the dominant K conductance. The defective temporal and spatial Kv1.3 distribution that we observed may contribute to the abnormal functions of SLE T cells.
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Affiliation(s)
- Stella A. Nicolaou
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Peter Szigligeti
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Lisa Neumeier
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Susan Molleran Lee
- Division of Hematology/Oncology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, 45267, USA
| | - Heather J. Duncan
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Shashi K. Kant
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Anne Barbara Mongey
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
| | - Alexandra H. Filipovich
- Division of Hematology/Oncology, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH, 45267, USA
| | - Laura Conforti
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH, 45267, USA
- Department of Molecular and Cellular Physiology, University of Cincinnati, Cincinnati, OH, 45267, USA
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Nicolaou SA, Neumeier L, Peng Y, Devor DC, Conforti L. The Ca(2+)-activated K(+) channel KCa3.1 compartmentalizes in the immunological synapse of human T lymphocytes. Am J Physiol Cell Physiol 2006; 292:C1431-9. [PMID: 17151145 PMCID: PMC2553516 DOI: 10.1152/ajpcell.00376.2006] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
T cell receptor engagement results in the reorganization of intracellular and membrane proteins at the T cell-antigen presenting cell interface forming the immunological synapse (IS), an event required for Ca(2+) influx. KCa3.1 channels modulate Ca(2+) signaling in activated T cells by regulating the membrane potential. Nothing is known regarding KCa3.1 membrane distribution during T cell activation. Herein, we determined whether KCa3.1 translocates to the IS in human T cells using YFP-tagged KCa3.1 channels. These channels showed electrophysiological and pharmacological properties identical to wild-type channels. IS formation was induced by either anti-CD3/CD28 antibody-coated beads for fixed microscopy experiments or Epstein-Barr virus-infected B cells for fixed and live cell microscopy. In fixed microscopy experiments, T cells were also immunolabeled for F-actin or CD3epsilon, which served as IS formation markers. The distribution of KCa3.1 was determined with confocal and fluorescence microscopy. We found that, upon T cell activation, KCa3.1 channels localize with F-actin and CD3epsilon to the IS but remain evenly distributed on the cell membrane when no stimulus is provided. Detailed imaging experiments indicated that KCa3.1 channels are recruited in the IS shortly after antigen presentation and are maintained there for at least 15-30 min. Interestingly, pretreatment of activated T cells with the specific KCa3.1 blocker TRAM-34 blocked Ca(2+) influx, but channel redistribution to the IS was not prevented. These results indicate that KCa3.1 channels are a part of the signaling complex that forms at the IS upon antigen presentation.
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Affiliation(s)
- Stella A. Nicolaou
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Lisa Neumeier
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - YouQing Peng
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
| | - Daniel C. Devor
- Department of Cell Biology and Physiology, University of Pittsburgh, Pittsburgh, PA 15216, USA
| | - Laura Conforti
- Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA
- Department of Molecular and Cellular Physiology, University of Cincinnati, Cincinnati, OH 45267, USA
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