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Wisniewski AM, Chancellor WZ, Young A, Money D, Beller JP, Charlton J, Lunardi N, Yang Z, Laubach VE, Mehaffey JH, Kron IL, Roeser ME. Adenosine 2A Receptor Agonism Improves Survival in Extracorporeal Cardiopulmonary Resuscitation. J Surg Res 2024; 301:404-412. [PMID: 39029264 DOI: 10.1016/j.jss.2024.06.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 05/20/2024] [Accepted: 06/22/2024] [Indexed: 07/21/2024]
Abstract
INTRODUCTION Despite resuscitation advances including extracorporeal cardiopulmonary resuscitation (ECPR), freedom from neurologic and myocardial insult after cardiac arrest remains unlikely. We hypothesized that adenosine 2A receptor (A2AR) agonism, which attenuates reperfusion injury, would improve outcomes in a porcine model of ECPR. METHODS Adult swine underwent 20 min of circulatory arrest followed by defibrillation and 6 h of ECPR. Animals were randomized to receive saline vehicle or A2AR agonist (ATL1223 or Regadenoson) infusion during extracorporeal membrane oxygenation. Animals were weaned off extracorporeal membrane oxygenation and monitored for 24 h. Clinical and biochemical end points were compared. RESULTS The administration of A2AR agonists increased survival (P = 0.01) after cardiac arrest compared to vehicle. Markers of neurologic damage including S100 calcium binding protein B and glial fibrillary acidic protein were significantly lower with A2AR agonist treatment. CONCLUSIONS In a model of cardiac arrest treated with ECPR, A2AR agonism increased survival at 24 h and reduced neurologic damage suggesting A2AR activation may be a promising therapeutic target after cardiac arrest.
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Affiliation(s)
- Alex M Wisniewski
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - William Z Chancellor
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - Andrew Young
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - Dustin Money
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - Jared P Beller
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - Jennifer Charlton
- Department of Pediatrics, University of Virginia Health System, Charlottesville, Virginia
| | - Nadia Lunardi
- Department of Anesthesiology, University of Virginia Health System, Charlottesville, Virginia
| | - Zequan Yang
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - Victor E Laubach
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - J Hunter Mehaffey
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - Irving L Kron
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia
| | - Mark E Roeser
- Department of Surgery, University of Virginia Health System, Charlottesville, Virginia.
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Mikdar M, Serra M, Colin E, Duval R, Gauthier EF, Lamarre Y, Colin Y, Le Van Kim C, Peyrard T, Koehl B, Azouzi S. Adenosine signaling inhibits erythropoiesis and promotes myeloid differentiation. Haematologica 2024; 109:175-185. [PMID: 37199120 PMCID: PMC10772517 DOI: 10.3324/haematol.2022.281823] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Accepted: 05/10/2023] [Indexed: 05/19/2023] Open
Abstract
Intracellular uptake of adenosine is essential for optimal erythroid commitment and differentiation of hematopoietic progenitor cells. The role of adenosine signaling is well documented in the regulation of blood flow, cell proliferation, apoptosis, and stem cell regeneration. However, the role of adenosine signaling in hematopoiesis remains unclear. In this study, we show that adenosine signaling inhibits the proliferation of erythroid precursors by activating the p53 pathway and hampers the terminal erythroid maturation. Furthermore, we demonstrate that the activation of specific adenosine receptors promotes myelopoiesis. Overall, our findings indicate that extracellular adenosine could be a new player in the regulation of hematopoiesis.
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Affiliation(s)
- Mahmoud Mikdar
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris
| | - Marion Serra
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris
| | - Elia Colin
- Laboratory of molecular mechanisms of hematologic disorders and therapeutic implications, Imagine Institute, UMR_ S1163, Inserm, Université Paris Cité
| | - Romain Duval
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris, France; Centre National de Référence pour les Groupes Sanguins, Établissement Français du Sang (EFS), Ile-de-France, F-75011 Paris
| | - Emilie-Fleur Gauthier
- Université Paris Cité, UMR_S1016, UMR 8104, Plateforme de Protéomique (3P5), Institut Cochin, Inserm, CNRS
| | - Yann Lamarre
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris
| | - Yves Colin
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris
| | - Caroline Le Van Kim
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris
| | - Thierry Peyrard
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris, France; Centre National de Référence pour les Groupes Sanguins, Établissement Français du Sang (EFS), Ile-de-France, F-75011 Paris
| | - Bérengère Koehl
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris, France; Sickle Cell Disease Center, Hematology Unit, Hôpital Robert Debré, Assistance Publique - Hôpitaux de Paris, F-75019 Paris
| | - Slim Azouzi
- Université Paris Cité and Université des Antilles, INSERM, BIGR, F-75014 Paris, France; Centre National de Référence pour les Groupes Sanguins, Établissement Français du Sang (EFS), Ile-de-France, F-75011 Paris.
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3
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Rabin J, Zhao Y, Mostafa E, Al-Suqi M, Fleischmann E, Conaway MR, Mann BJ, Chhabra P, Brayman KL, Krupnick A, Linden J, Lau CL. Regadenoson for the treatment of COVID-19: A five case clinical series and mouse studies. PLoS One 2023; 18:e0288920. [PMID: 37566593 PMCID: PMC10420352 DOI: 10.1371/journal.pone.0288920] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 07/04/2023] [Indexed: 08/13/2023] Open
Abstract
BACKGROUND Adenosine inhibits the activation of most immune cells and platelets. Selective adenosine A2A receptor (A2AR) agonists such as regadenoson (RA) reduce inflammation in most tissues, including lungs injured by hypoxia, ischemia, transplantation, or sickle cell anemia, principally by suppressing the activation of invariant natural killer T (iNKT) cells. The anti-inflammatory effects of RA are magnified in injured tissues due to induction in immune cells of A2ARs and ecto-enzymes CD39 and CD73 that convert ATP to adenosine in the extracellular space. Here we describe the results of a five patient study designed to evaluate RA safety and to seek evidence of reduced cytokine storm in hospitalized COVID-19 patients. METHODS AND FINDINGS Five COVID-19 patients requiring supplemental oxygen but not intubation (WHO stages 4-5) were infused IV with a loading RA dose of 5 μg/kg/h for 0.5 h followed by a maintenance dose of 1.44 μg/kg/h for 6 hours, Vital signs and arterial oxygen saturation were recorded, and blood samples were collected before, during and after RA infusion for analysis of CRP, D-dimer, circulating iNKT cell activation state and plasma levels of 13 proinflammatory cytokines. RA was devoid of serious side effects, and within 24 hours from the start of infusion was associated with increased oxygen saturation (93.8 ± 0.58 vs 96.6 ± 1.08%, P<0.05), decreased D-dimer (754 ± 17 vs 518 ± 98 ng/ml, P<0.05), and a trend toward decreased CRP (3.80 ± 1.40 vs 1.98 ± 0.74 mg/dL, P = 0.075). Circulating iNKT cells, but not conventional T cells, were highly activated in COVID-19 patients (65% vs 5% CD69+). RA infusion for 30 minutes reduced iNKT cell activation by 50% (P<0.01). RA infusion for 30 minutes did not influence plasma cytokines, but infusion for 4.5 or 24 hours reduced levels of 11 of 13 proinflammatory cytokines. In separate mouse studies, subcutaneous RA infusion from Alzet minipumps at 1.44 μg/kg/h increased 10-day survival of SARS-CoV-2-infected K18-hACE2 mice from 10 to 40% (P<0.001). CONCLUSIONS Infused RA is safe and produces rapid anti-inflammatory effects mediated by A2A adenosine receptors on iNKT cells and possibly in part by A2ARs on other immune cells and platelets. We speculate that iNKT cells are activated by release of injury-induced glycolipid antigens and/or alarmins such as IL-33 derived from virally infected type II epithelial cells which in turn activate iNKT cells and secondarily other immune cells. Adenosine released from hypoxic tissues, or RA infused as an anti-inflammatory agent decrease proinflammatory cytokines and may be useful for treating cytokine storm in patients with Covid-19 or other inflammatory lung diseases or trauma.
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Affiliation(s)
- Joseph Rabin
- Department of Surgery, Division of Thoracic, University of Maryland, Baltimore, Maryland, United States of America
| | - Yunge Zhao
- Department of Surgery, Division of Thoracic, University of Maryland, Baltimore, Maryland, United States of America
| | - Ezzat Mostafa
- Department of Surgery, Division of Thoracic, University of Maryland, Baltimore, Maryland, United States of America
| | - Manal Al-Suqi
- Department of Surgery, Division of Thoracic, University of Maryland, Baltimore, Maryland, United States of America
| | - Emily Fleischmann
- Department of Surgery, Division of Thoracic, University of Maryland, Baltimore, Maryland, United States of America
| | - Mark R. Conaway
- Department of Public Health Sciences, University of Virginia, Charlottesville, Virginia, United States of America
| | - Barbara J. Mann
- Department of Medicine, Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, United States of America
| | - Preeti Chhabra
- Department of Surgery, University of Virginia, Charlottesville, Virginia, United States of America
| | - Kenneth L. Brayman
- Department of Surgery, University of Virginia, Charlottesville, Virginia, United States of America
| | - Alexander Krupnick
- Department of Surgery, Division of Thoracic, University of Maryland, Baltimore, Maryland, United States of America
| | - Joel Linden
- Department of Surgery, Division of Thoracic, University of Maryland, Baltimore, Maryland, United States of America
- Department of Medicine, Division of Infectious Diseases and International Health, University of Virginia, Charlottesville, Virginia, United States of America
| | - Christine L. Lau
- Department of Surgery, Division of Thoracic, University of Maryland, Baltimore, Maryland, United States of America
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Wang Q, Zennadi R. The Role of RBC Oxidative Stress in Sickle Cell Disease: From the Molecular Basis to Pathologic Implications. Antioxidants (Basel) 2021; 10:antiox10101608. [PMID: 34679742 PMCID: PMC8533084 DOI: 10.3390/antiox10101608] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 10/04/2021] [Accepted: 10/06/2021] [Indexed: 01/14/2023] Open
Abstract
Sickle cell disease (SCD) is an inherited monogenic disorder and the most common severe hemoglobinopathy in the world. SCD is characterized by a point mutation in the β-globin gene, which results in hemoglobin (Hb) S production, leading to a variety of mechanistic and phenotypic changes within the sickle red blood cell (RBC). In SCD, the sickle RBCs are the root cause of the disease and they are a primary source of oxidative stress since sickle RBC redox state is compromised due to an imbalance between prooxidants and antioxidants. This imbalance in redox state is a result of a continuous production of reactive oxygen species (ROS) within the sickle RBC caused by the constant endogenous Hb autoxidation and NADPH oxidase activation, as well as by a deficiency in the antioxidant defense system. Accumulation of non-neutralized ROS within the sickle RBCs affects RBC membrane structure and function, leading to membrane integrity deficiency, low deformability, phosphatidylserine exposure, and release of micro-vesicles. These oxidative stress-associated RBC phenotypic modifications consequently evoke a myriad of physiological changes involved in multi-system manifestations. Thus, RBC oxidative stress in SCD can ultimately instigate major processes involved in organ damage. The critical role of the sickle RBC ROS production and its regulation in SCD pathophysiology are discussed here.
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5
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Salinas Cisneros G, Thein SL. Research in Sickle Cell Disease: From Bedside to Bench to Bedside. Hemasphere 2021; 5:e584. [PMID: 34095767 PMCID: PMC8171370 DOI: 10.1097/hs9.0000000000000584] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 04/17/2021] [Indexed: 01/25/2023] Open
Abstract
Sickle cell disease (SCD) is an exemplar of bidirectional translational research, starting with a remarkable astute observation of the abnormally shaped red blood cells that motivated decades of bench research that have now translated into new drugs and genetic therapies. Introduction of hydroxyurea (HU) therapy, the only SCD-modifying treatment for >30 years and now standard care, was initiated through another clinical observation by a pediatrician. While the clinical efficacy of HU is primarily due to its fetal hemoglobin (HbF) induction, the exact mechanism of how it increases HbF remains not fully understood. Unraveling of the molecular mechanism of how HU increases HbF has provided insights on the development of new HbF-reactivating agents in the pipeline. HU has other salutary effects, reduction of cellular adhesion to the vascular endothelium and inflammation, and dissecting these mechanisms has informed bench-both cellular and animal-research for development of the 3 recently approved agents: endari, voxelotor, and crizanlizumab; truly, a bidirectional bench to bedside translation. Decades of research to understand the mechanisms of fetal to adult hemoglobin have also culminated in promising anti-sickling genetic therapies and the first-in-human studies of reactivating an endogenous (γ-globin) gene HBG utilizing innovative genomic approaches.
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Affiliation(s)
- Gabriel Salinas Cisneros
- Sickle Cell Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
- Division of Hematology and Oncology, Children’s National Medical Center, Washington, District of Columbia, USA
| | - Swee Lay Thein
- Sickle Cell Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, Maryland, USA
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6
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Abstract
Sickle cell disease (SCD) afflicts millions of people worldwide but is referred to as an orphan disease in the United States. Over the past several decades, there has been an increasing understanding of the pathophysiology of SCD and its complications. While most individuals with SCD in resource-rich countries survive into adulthood, the life expectancy of patients with SCD remains substantially shorter than for the general African-American population. SCD can be cured using hematopoietic stem cell transplantation and possibly gene therapy, but these treatment approaches are not available to most patients, the majority of whom reside in low- and middle-income countries. Until relatively recently, only one drug, hydroxyurea, was approved by the US Food and Drug Administration to ameliorate disease severity. Multiple other drugs (L-glutamine, crizanlizumab, and voxelotor) have recently been approved for the treatment of SCD, with several others at various stages of clinical testing. The availability of multiple agents to treat SCD raises questions related to the choice of appropriate drug therapy, combination of multiple agents, and affordability of recently approved products. The enthusiasm for new drug development provides opportunities to involve patients in low- and middle-income nations in the testing of potentially disease-modifying therapies and has the potential to contribute to capacity building in these environments. Demonstration that these agents, alone or in combination, can prevent or decrease end-organ damage would provide additional evidence for the role of drug therapies in improving outcomes in SCD.
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Affiliation(s)
- Parul Rai
- Department of Hematology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Kenneth I. Ataga
- Center for Sickle Cell Disease, University of Tennessee Health Science Center, Memphis, TN, USA
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7
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de Azevedo JTC, Malmegrim KCR. Immune mechanisms involved in sickle cell disease pathogenesis: current knowledge and perspectives. Immunol Lett 2020; 224:1-11. [PMID: 32437728 DOI: 10.1016/j.imlet.2020.04.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/02/2020] [Accepted: 04/18/2020] [Indexed: 12/18/2022]
Abstract
Sickle cell disease (SCD) is caused by a single point mutation in the β-chain of the hemoglobin gene that results in the replacement of glutamic acid with valine in the hemoglobin protein. However, recent studies have demonstrated that alterations in several other genes, especially immune related genes, may be associated with complications of SCD. In fact, higher chronic inflammatory status is related to more severe clinical symptoms in SCD patients, suggesting crucial roles of the immune system in SCD physiopathology. Nevertheless, although participation of innate immune cells in SCD pathogenesis has been broadly and extensively described, little is known about the roles of the adaptive immune system in this disease. In addition, the influence of treatments on the immune system of SCD patients and their complications (such as alloimmunization) are not yet completely understood. Thus, we reviewed the current knowledge about the immune mechanisms involved in SCD pathogenesis. We suggest recommendations for future studies to allow for a broader understanding of SCD pathogenesis, helping in the development of new therapies and improvement in the life quality and expectancy of patients.
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Affiliation(s)
- Júlia Teixeira Cottas de Azevedo
- Center for Cell-based Therapy, Regional Blood Center of Ribeirão Preto, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil; Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Kelen Cristina Ribeiro Malmegrim
- Center for Cell-based Therapy, Regional Blood Center of Ribeirão Preto, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil; Department of Clinical, Toxicological and Bromatological Analysis, School of Pharmaceutical Sciences of Ribeirão Preto, University of São Paulo, Ribeirão Preto, Brazil.
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8
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Borah P, Deka S, Mailavaram RP, Deb PK. P1 Receptor Agonists/Antagonists in Clinical Trials - Potential Drug Candidates of the Future. Curr Pharm Des 2020; 25:2792-2807. [PMID: 31333097 DOI: 10.2174/1381612825666190716111245] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/03/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Adenosine mediates various physiological and pathological conditions by acting on its four P1 receptors (A1, A2A, A2B and A3 receptors). Omnipresence of P1 receptors and their activation, exert a wide range of biological activities. Thus, its modulation is implicated in various disorders like Parkinson's disease, asthma, cardiovascular disorders, cancer etc. Hence these receptors have become an interesting target for the researchers to develop potential therapeutic agents. Number of molecules were designed and developed in the past few years and evaluated for their efficacy in various disease conditions. OBJECTIVE The main objective is to provide an overview of new chemical entities which have crossed preclinical studies and reached clinical trials stage following their current status and future prospective. METHODS In this review we discuss current status of the drug candidates which have undergone clinical trials and their prospects. RESULTS Many chemical entities targeting various subtypes of P1 receptors are patented; twenty of them have crossed preclinical studies and reached clinical trials stage. Two of them viz adenosine and regadenoson are approved by the Food and Drug Administration. CONCLUSION This review is an attempt to highlight the current status, progress and probable future of P1 receptor ligands which are under clinical trials as promising novel therapeutic agents and the direction in which research should proceed with a view to come out with novel therapeutic agents.
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Affiliation(s)
- Pobitra Borah
- Pratiksha Institute of Pharmaceutical Sciences, Panikhaiti, Chandrapur Road, Guwahati, Assam, India
| | - Satyendra Deka
- Pratiksha Institute of Pharmaceutical Sciences, Panikhaiti, Chandrapur Road, Guwahati, Assam, India
| | - Raghu Prasad Mailavaram
- Department of Pharmaceutical Chemistry, Shri Vishnu College of Pharmacy, Vishnupur (Affiliated to Andhra University), Bhimavaram, W.G. Dist., AP, India
| | - Pran Kishore Deb
- Faculty of Pharmacy, Philadelphia University, Amman, PO Box-1, 19392, Jordan
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9
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Abstract
Despite sickle cell disease (SCD) being the most common and severe inherited condition worldwide, therapeutic options are limited. To date, hydroxyurea remains the main treatment option in SCD. However, in the last decade the numbers of interventional clinical trials focussing on therapies for SCD have increased significantly. Many new drugs with various pharmacological targets have emerged and, although the majority have failed to show benefit in clinical trials, some have produced encouraging results. It seems probable that more drugs will soon become available for the treatment of SCD. Furthermore, promising clinical trials with improved outcomes have recently changed the perspective of curative therapies in SCD. Nevertheless, the application of novel therapeutic agents and potential curative treatments will most likely be limited to high-income countries and, thus, will remain unavailable for the majority of people with SCD in the foreseeable future.
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Affiliation(s)
- Amina Nardo-Marino
- Centre for Haemoglobinopathies, Department of Haematology, Herlev and Gentofte Hospital, University of Copenhagen, Herlev, Denmark
| | - Valentine Brousse
- Sickle Cell Disease Reference Center, Department of General Pediatrics and Pediatric Infectious Diseases, Necker-Enfants Malades Hospital, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - David Rees
- Department of Haematological Medicine, King's College London, King's College Hospital, London, UK
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10
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Lau CL, Beller JP, Boys JA, Zhao Y, Phillips J, Cosner M, Conaway MR, Petroni G, Charles EJ, Mehaffey JH, Mannem HC, Kron IL, Krupnick AS, Linden J. Adenosine A2A receptor agonist (regadenoson) in human lung transplantation. J Heart Lung Transplant 2020; 39:563-570. [PMID: 32503727 DOI: 10.1016/j.healun.2020.02.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Revised: 12/20/2019] [Accepted: 02/06/2020] [Indexed: 10/25/2022] Open
Abstract
BACKGROUND Currently, there are no clinically approved treatments for ischemia-reperfusion injury after lung transplantation. Pre-clinical animal models have demonstrated a promising efficacy of adenosine 2A receptor (A2AR) agonists as a treatment option for reducing ischemia-reperfusion injury. The purpose of this human study, is to conduct a Phase I clinical trial for evaluating the safety of continuous infusion of an A2AR agonist in lung transplant recipients. METHODS An adaptive, two-stage continual reassessment trial was designed to evaluate the safety of regadenoson (A2AR agonist) in the setting of lung transplantation. Continuous infusion of regadenoson was administered to lung transplant recipients that was started at the time of skin incision. Adverse events and dose-limiting toxicities, as pre-determined by a study team and assessed by a clinical team and an independent safety monitor, were the primary end-points for safety in this trial. RESULTS Between January 2018 and March 2019, 14 recipients were enrolled in the trial. Of these, 10 received the maximum infused dose of 1.44 µg/kg/min for 12 hours. No dose-limiting toxicities were observed. The steady-state plasma regadenoson levels sampled before the reperfusion of the first lung were 0.98 ± 0.46 ng/ml. There were no mortalities within 30 days. CONCLUSIONS Regadenoson, an A2AR agonist, can be safely infused in the setting of lung transplantation with no dose-limiting toxicities or drug-related mortality. Although not powered for the evaluation of secondary end-points, the results of this trial and the outcome of pre-clinical studies warrant further investigation with a Phase II randomized controlled trial.
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Affiliation(s)
- Christine L Lau
- Department of Surgery, University of Maryland, Baltimore, Maryland.
| | - Jared P Beller
- Department of Surgery, University of Virginia, Charlottesville, Virginia
| | - Joshua A Boys
- Division of Cardiovascular and Thoracic Surgery, Department of Surgery, University of California, San Diego, California
| | - Yunge Zhao
- Department of Surgery, University of Maryland, Baltimore, Maryland
| | - Jennifer Phillips
- Department of Surgery, University of Virginia, Charlottesville, Virginia
| | - Michael Cosner
- Department of Surgery, University of Virginia, Charlottesville, Virginia
| | - Mark R Conaway
- Public Health Sciences, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Gina Petroni
- Public Health Sciences, University of Virginia School of Medicine, Charlottesville, Virginia
| | - Eric J Charles
- Department of Surgery, University of Virginia, Charlottesville, Virginia
| | - J H Mehaffey
- Department of Surgery, University of Virginia, Charlottesville, Virginia
| | - Hannah C Mannem
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, University of Virginia, Charlottesville, Virginia
| | - Irving L Kron
- Department of Surgery, University of Virginia, Charlottesville, Virginia; Department of Surgery, University of Arizona Health Sciences, Tucson, Arizona
| | | | - Joel Linden
- Division of Developmental Immunology, La Jolla Institute for Immunology and Department of Pharmacology, University of California, San Diego, California
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11
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Allali S, Maciel TT, Hermine O, de Montalembert M. Innate immune cells, major protagonists of sickle cell disease pathophysiology. Haematologica 2020; 105:273-283. [PMID: 31919091 PMCID: PMC7012475 DOI: 10.3324/haematol.2019.229989] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 09/26/2019] [Indexed: 12/30/2022] Open
Abstract
Sickle cell disease (SCD), considered the most common monogenic disease worldwide, is a severe hemoglobin disorder. Although the genetic and molecular bases have long been characterized, the pathophysiology remains incompletely elucidated and therapeutic options are limited. It has been increasingly suggested that innate immune cells, including monocytes, neutrophils, invariant natural killer T cells, platelets and mast cells, have a role in promoting inflammation, adhesion and pain in SCD. Here we provide a thorough review of the involvement of these novel, major protagonists in SCD pathophysiology, highlighting recent evidence for innovative therapeutic perspectives.
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Affiliation(s)
- Slimane Allali
- Department of General Pediatrics and Pediatric Infectious Diseases, Reference Center for Sickle Cell Disease, Necker Hospital for Sick Children, Assistance Publique - Hôpitaux de Paris (AP-HP), Paris Descartes University, Paris .,Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, Paris Descartes - Sorbonne Paris Cite University, Imagine Institute, Inserm U1163, Paris.,Laboratory of Excellence GR-Ex, Paris
| | - Thiago Trovati Maciel
- Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, Paris Descartes - Sorbonne Paris Cite University, Imagine Institute, Inserm U1163, Paris.,Laboratory of Excellence GR-Ex, Paris
| | - Olivier Hermine
- Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, Paris Descartes - Sorbonne Paris Cite University, Imagine Institute, Inserm U1163, Paris.,Laboratory of Excellence GR-Ex, Paris.,Department of Hematology, Necker Hospital for Sick Children, AP-HP, Paris Descartes University, Paris, France
| | - Mariane de Montalembert
- Department of General Pediatrics and Pediatric Infectious Diseases, Reference Center for Sickle Cell Disease, Necker Hospital for Sick Children, Assistance Publique - Hôpitaux de Paris (AP-HP), Paris Descartes University, Paris .,Laboratory of Excellence GR-Ex, Paris
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12
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Ballas SK. The Evolving Pharmacotherapeutic Landscape for the Treatment of Sickle Cell Disease. Mediterr J Hematol Infect Dis 2020; 12:e2020010. [PMID: 31934320 PMCID: PMC6951351 DOI: 10.4084/mjhid.2020.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 12/17/2019] [Indexed: 01/02/2023] Open
Abstract
Sickle cell disease (SCD) is an extremely heterogeneous disease that has been associated with global morbidity and early mortality. More effective and inexpensive therapies are needed. During the last five years, the landscape of the pharmacotherapy of SCD has changed dramatically. Currently, 54 drugs have been used or under consideration to use for the treatment of SCD. These fall into 3 categories: the first category includes the four drugs (Hydroxyurea, L-Glutamine, Crizanlizumab tmca and Voxelotor) that have been approved by the United States Food and Drug Administration (FDA) based on successful clinical trials. The second category includes 22 drugs that failed, discontinued or terminated for now and the third category includes 28 drugs that are actively being considered for the treatment of SCD. Crizanlizumab and Voxelotor are included in the first and third categories because they have been used in more than one trial. New therapies targeting multiple pathways in the complex pathophysiology of SCD have been achieved or are under continued investigation. The emerging trend seems to be the use of multimodal drugs (i.e. drugs that have different mechanisms of action) to treat SCD similar to the use of multiple chemotherapeutic agents to treat cancer.
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Affiliation(s)
- Samir K Ballas
- Cardeza Foundation for Hematologic Research, Department of Medicine, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
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Adenosine Receptor Agonists Exhibit Anti-Platelet Effects and the Potential to Overcome Resistance to P2Y 12 Receptor Antagonists. Molecules 2019; 25:molecules25010130. [PMID: 31905703 PMCID: PMC6982709 DOI: 10.3390/molecules25010130] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 12/16/2019] [Accepted: 12/25/2019] [Indexed: 11/30/2022] Open
Abstract
Large inter-individual variation in platelet response to endogenous agonists and pharmacological agents, including resistance to antiplatelet therapy, prompts a search for novel platelet inhibitors and development new antithrombotic strategies. The present in vitro study evaluates the beneficial effects of three adenosine receptor (AR) agonists (regadenoson, LUF 5835 and NECA), different in terms of their selectivity for platelet adenosine receptors, when used alone and in combination with P2Y12 inhibitors, such as cangrelor or prasugrel metabolite. The anti-platelet effects of AR agonists were evaluated in healthy subjects (in the whole group and after stratification of individuals into high- and low-responders to P2Y12 inhibitors), using whole blood techniques, under flow (thrombus formation) and static conditions (study of platelet activation and aggregation). Compared to P2Y12 antagonists, AR agonists were much less or not effective under static conditions, but demonstrated similar antiplatelet activity in flow. In most cases, AR agonists significantly enhanced the anti-platelet effect of P2Y12 antagonists, despite possessing different selectivity profiles and antiplatelet activities. Importantly, their inhibitory effects in combination with P2Y12 antagonists were similar in high- and low-responders to P2Y12 inhibitors. In conclusion, a combination of anti-platelet agents acting via the P1 and P2 purinergic receptors represents a promising alternative to existing antithrombotic therapy.
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Ansari J, Gavins FNE. Ischemia-Reperfusion Injury in Sickle Cell Disease: From Basics to Therapeutics. THE AMERICAN JOURNAL OF PATHOLOGY 2019; 189:706-718. [PMID: 30904156 DOI: 10.1016/j.ajpath.2018.12.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 11/17/2018] [Accepted: 12/07/2018] [Indexed: 12/17/2022]
Abstract
Sickle cell disease (SCD) is one of the most common hereditary hemoglobinopathies worldwide, affecting almost 400,000 newborns globally each year. It is characterized by chronic hemolytic anemia and endothelial dysfunction, resulting in a constant state of disruption of the vascular system and leading to recurrent episodes of ischemia-reperfusion injury (I/RI) to multiple organ systems. I/RI is a fundamental vascular pathobiological paradigm and contributes to morbidity and mortality in a wide range of conditions, including myocardial infarction, stroke, acute kidney injury, and transplantation. I/RI is characterized by an initial restriction of blood supply to an organ, which can lead to ischemia, followed by the subsequent restoration of perfusion and concomitant reoxygenation. Recent advances in the pathophysiology of SCD have led to an understanding that many of the consequences of this disease can be explained by mechanisms associated with I/RI. The following review focuses on the evolving pathobiology of SCD, how various complications of SCD can be attributed to I/RI, and the role of timely therapeutic intervention(s) based on targeting mediators or pathways that influence I/R insult.
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Affiliation(s)
- Junaid Ansari
- Department of Molecular & Cellular Physiology, Louisiana State University Health Sciences Center Shreveport, Shreveport, Louisiana
| | - Felicity N E Gavins
- Department of Molecular & Cellular Physiology, Louisiana State University Health Sciences Center Shreveport, Shreveport, Louisiana.
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Mahran MA, Ismail MT, Abdelkader EH. 100 years of sickle cell disease research: etiology, pathophysiology and rational drug design (part 1). BENI-SUEF UNIVERSITY JOURNAL OF BASIC AND APPLIED SCIENCES 2019. [DOI: 10.1186/s43088-019-0016-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
AbstractBackgroundSickle cell disease (SCD) is a chronic hemolytic disease caused by an altered hemoglobin molecule (HbS) and was first termed as a molecular disease. Glutamic acid in the normal hemoglobin molecule (HbA), was replaced by valine in HbS at the sixth position of both β-chains. This alteration was proved to be due to a single point mutation GTG instead of GAG in the genetic code. Since the discovery of sickle cell disease in 1910, great efforts have been done to study this disease on a molecular level. These efforts aimed to identify the disease etiology, pathophysiology, and finally to discover efficient treatment. Despite the tremendous work of many research groups all over the world, the only approved drug up to this moment, for the treatment of SCD is the hydroxyurea.Main textIn this review, the antisickling pharmaco-therapeutics will be classified into two major groups: hemoglobin site directed modifiers and ex-hemoglobin effectors. The first class will be discussed in details, here in, focusing on the most important figures in the way of the rational drug design for SCD treatment aiming to help scientists solve the mystery of this problem and to get clear vision toward possible required therapy for SCD.ConclusionDespite the large number of the antisickling candidates that have been reached clinical studies yet, none of them has been introduced to the market. This may be due to the fact that hemoglobin is a large molecule with different target sites, which requires highly potent therapeutic agent. With this potency, these drugs should be safe, with acceptable oral pharmacokinetic and pharmacodynamic properties. Such ideal drug candidate needs more efforts to be developed.
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Abstract
BACKGROUND Sickle cell disease is an autosomal recessive inherited haemoglobinopathy which causes painful vaso-occlusive crises due to sickle red blood cell dehydration. Vaso-occlusive crises are common painful events responsible for a variety of clinical complications; overall mortality is increased and life expectancy decreased compared to the general population. Experimental studies suggest that intravenous magnesium has proven to be well-tolerated in individuals hospitalised for the immediate relief of acute (sudden onset) painful crisis and has the potential to decrease the length of hospital stay. Some in vitro studies and open studies of long-term oral magnesium showed promising effect on pain relief but failed to show its efficacy. The studies show that oral magnesium therapy may prevent sickle red blood cell dehydration and prevent recurrent painful episodes. There is a need to access evidence for the impact of oral and intravenous magnesium effect on frequency of pain, length of hospital stay and quality of life. This is an updated version of the review. OBJECTIVES To evaluate the effects of short-term intravenous magnesium on the length of hospital stay and quality of life in children and adults with sickle cell disease. To determine the effects of long-term oral magnesium therapy on the frequency of painful crises and the quality of life in children and adults with sickle cell disease. SEARCH METHODS We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books.Date of last search of the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register: 03 February 2019.Date of last search of other resources (clinical trials registries): 04 April 2019. SELECTION CRITERIA We searched for published and unpublished randomized controlled studies of oral or intravenous magnesium compared to placebo or no magnesium. DATA COLLECTION AND ANALYSIS Authors independently assessed the study quality and extracted the data using standard Cochrane methodologies. MAIN RESULTS We included five randomized placebo-controlled studies with a total of 386 participants (aged three to 53 years). Of these, two shorter parallel studies (n = 306) compared intravenous magnesium sulphate to placebo (normal saline) for admission to hospital due to a vaso-occlusive crisis, for which we were able to analyse data. The quality of evidence was moderate for studies in this comparison, mainly due to limitations due to risk of bias and imprecision. Two of the three longer-term studies comparing oral magnesium pidolate to placebo had a cross-over design. The third was a parallel factorial study which compared hydroxyurea and oral magnesium to each other and to placebo over a longer period of time; we only present the comparison of oral magnesium to placebo from this study. The quality of evidence was very low with uncertainty of the estimation.The eight-hourly dose levels in the two studies of intravenous magnesium were different; one used 100 mg/kg while the second used 40 mg/kg. Only one of these studies (n = 104) reported the mean daily pain score while hospitalised (a non-significant difference between groups, moderate quality evidence). The second study (n = 202) reported a number of child- and parent-reported quality of life scores. None of the scores showed any difference between treatment groups (low quality evidence). Data from one study (n = 106) showed no difference in length of stay in hospital between groups (low quality evidence). Both studies reported on adverse events, but not defined by severity as we had planned. One study showed significantly more participants receiving intravenous magnesium experienced warmth at infusion site compared to placebo; there were no differences between groups for other adverse events (low quality evidence).Three studies (n = 80) compared oral magnesium pidolate to placebo. None of them reported data which we were able to analyse. One study (n = 24) reported on the number of painful days and stated there was no difference between two groups (low quality evidence). None of the studies reported on quality of life or length of hospital stay. Two studies (n = 68) reported there were no differences in levels of magnesium in either plasma or red blood cells (moderate quality evidence). Two studies (n = 56) reported adverse events. One reported episodes of mild diarrhoea and headache, all of which resolved without stopping treatment. The second study reported adverse events as gastrointestinal disorders, headache or migraine, upper respiratory infections and rash; which were all evenly distributed across treatment groups (moderate quality evidence). AUTHORS' CONCLUSIONS Moderate to low quality evidence showed neither intravenous magnesium and oral magnesium therapy has an effect on reducing painful crisis, length of hospital stay and changing quality of life in treating sickle cell disease. Therefore, no definitive conclusions can be made regarding its clinical benefit. Further randomized controlled studies, perhaps multicentre, are necessary to establish whether intravenous and oral magnesium therapies have any effect on improving the health of people with sickle cell disease.
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Affiliation(s)
- Nan Nitra Than
- Faculty of Medicine, Melaka‐Manipal Medical College (MMMC), Manipal Academy of Higher Education(MAHE)Department of Community MedicineMelakaMalaysia75150
| | - Htoo Htoo Kyaw Soe
- Faculty of Medicine, Melaka‐Manipal Medical College, Manipal Academy of Higher Education (MAHE)Department of Community MedicineJalan Batu HamparBukit BaruMelakaMalaysia75150
| | - Senthil K Palaniappan
- NHS trustDepartment of Medicine, University Hospitals of LeicesterLeicester Royal InfirmaryLeicesterUKLE1 5WW
| | - Adinegara BL Abas
- Melaka‐Manipal Medical College (Manipal Academy of Higher Education)Department of Community MedicineJalan Batu HamparBukit BaruMelakaMalaysia75150
| | - Lucia De Franceschi
- University of Verona‐AOUI VeronaDepartment of MedicinePolilinico GB RossiVeronaItaly37134
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Carden MA, Little J. Emerging disease-modifying therapies for sickle cell disease. Haematologica 2019; 104:1710-1719. [PMID: 31413089 PMCID: PMC6717563 DOI: 10.3324/haematol.2018.207357] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/10/2019] [Indexed: 12/20/2022] Open
Abstract
Sickle cell disease afflicts millions of people worldwide and approximately 100,000 Americans. Complications are myriad and arise as a result of complex pathological pathways ‘downstream’ to a point mutation in DNA, and include red blood cell membrane damage, inflammation, chronic hemolytic anemia with episodic vaso-occlusion, ischemia and pain, and ultimately risk of cumulative organ damage with reduced lifespan of affected individuals. The National Heart, Lung, and Blood Institute’s 2014 evidence-based guideline for sickle cell disease management states that additional research is needed before investigational curative therapies will be widely available to most patients with sickle cell disease. To date, sickle cell disease has been cured by hematopoietic stem cell transplantation in approximately 1,000 people, most of whom were children, and significantly ameliorated by gene therapy in a handful of subjects who have only limited follow-up thus far. During a timespan in which over 20 agents were approved for the treatment of cystic fibrosis by the Food and Drug Administration, similar approval was granted for only two drugs for sickle cell disease (hydroxyurea and L-glutamine) despite the higher prevalence of sickle cell disease. This trajectory appears to be changing, as the lack of multimodal agent therapy in sickle cell disease has spurred engagement among many in academia and industry who, in the last decade, have developed new drugs poised to prevent complications and alleviate suffering. Identified therapeutic strategies include fetal hemoglobin induction, inhibition of intracellular HbS polymerization, inhibition of oxidant stress and inflammation, and perturbation of the activation of the endothelium and other blood components (e.g. platelets, white blood cells, coagulation proteins) involved in the pathophysiology of sickle cell disease. In this article, we present a crash-course review of disease-modifying approaches (minus hematopoietic stem cell transplant and gene therapy) for patients with sickle cell disease currently, or recently, tested in clinical trials in the era following approval of hydroxyurea.
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Affiliation(s)
- Marcus A Carden
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, University of North Carolina Chapel Hill School of Medicine.,Department of Medicine, Division of Hematology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Jane Little
- Department of Medicine, Division of Hematology, University of North Carolina Chapel Hill School of Medicine, Chapel Hill, NC, USA
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Contrast-enhanced ultrasound detects changes in microvascular blood flow in adults with sickle cell disease. PLoS One 2019; 14:e0218783. [PMID: 31276520 PMCID: PMC6611596 DOI: 10.1371/journal.pone.0218783] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 06/10/2019] [Indexed: 11/19/2022] Open
Abstract
In patients with sickle cell disease (SCD), poor outcome measures compromise the potential success of clinical trials. Contrast-enhanced ultrasound (CEUS) is a technique that can non-invasively quantify deep tissue microvascular blood flow. We tested the hypothesis that CEUS of forearm skeletal muscle could be used to: 1) assess microvascular abnormalities that occur during vaso-occlusive crisis; and 2) test new therapies for SCD that are targeted to improving the status of the microcirculation. We performed a prospective study, CEUS perfusion imaging of resting forearm muscle was performed in adults with SCD: 1) during and after a pain episode, and 2) before, during, and after a 24-hour infusion of the investigative agent, regadenoson, an adenosine A2A agonist. CEUS destruction-replenishment time-intensity data were analyzed to measure microvascular blood flow, as well as its components, microvascular blood volume and flux rate. Serial CEUS measurements were obtained in 32 adults with SCD. For the studies during crisis, there was a 30% reduction in microvascular blood flow compared to steady-state (p = 0.031), a reduction that was largely due to microvascular flux rate. For the regadenoson group, a non-significant 25% increase in flux rate and 9% increase in microvascular blood flow compared to baseline were detected during infusion. In a study of adults with SCD, CEUS detected changes in microvascular blood flow associated with vaso-occlusive crises. No changes were found during an infusion of the adenosine A2A agonist, regadenoson. This study provides preliminary evidence that CEUS could detect blood flow changes consistent with SCD physiology.
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Allali S, Dietrich C, Machavoine F, Rignault-Bricard R, Brousse V, de Montalembert M, Hermine O, Maciel TT, Leite-de-Moraes M. Innate-like T cells in children with sickle cell disease. PLoS One 2019; 14:e0219047. [PMID: 31251783 PMCID: PMC6599217 DOI: 10.1371/journal.pone.0219047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 06/15/2019] [Indexed: 01/05/2023] Open
Abstract
Background The implication of lymphocytes in sickle cell disease pathogenesis is supported by a number of recent reports. These studies provided evidence for the activation of invariant natural killer T (iNKT) cells in adult patients, but did not investigate the involvement of other innate-like T cell subsets so far. Methods Here we present a monocentric prospective observational study evaluating the number and functional properties of both circulating conventional and innate-like T cells, namely iNKT, Mucosal-Associated Invariant T (MAIT) and gammadelta (γδ) T cells in a cohort of 39 children with sickle cell disease. Results Relative to age-matched healthy controls, we found that patients had a higher frequency of IL-13- and IL-17-producing CD4+ T cells, as well as higher MAIT cell counts with an increased frequency of IL-17-producing MAIT cells. Patients also presented increased Vδ2 γδ T cell counts, especially during vaso-occlusive crisis, and a lower frequency of IFNγ-producing Vδ2 γδ T cells, except during crisis. iNKT cell counts and the frequency of IFNγ-producing iNKT cells were unchanged compared to controls. Our study revealed positive correlations between 1) the frequency of IFNγ-producing CD4+, CD8+ and Vδ2 γδ T cells and the number of hospitalizations for vaso-occlusive crisis in the previous year; 2) the frequency of IFNγ-producing iNKT cells and patients’ age and 3) the frequency of IL-17-producing Vδ2 γδ T cells and hemoglobin S level. Conclusion These results strongly suggest a role of innate-like T cells in sickle cell disease pathophysiology, especially that of IL-17-producing MAIT and γδ T cells.
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Affiliation(s)
- Slimane Allali
- Department of General Pediatrics and Pediatric Infectious Diseases, Hôpital Necker-Enfants malades, Paris Descartes – Sorbonne Paris Cité University, Assistance Publique-Hôpitaux de Paris, Paris, France
- Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, Paris Descartes – Sorbonne Paris Cité University, Imagine Institute, Inserm U1163, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
- * E-mail: (SA); (MLM)
| | - Céline Dietrich
- Laboratory of Immunoregulation and Immunopathology, Institut Necker-Enfants malades, Centre National de la Recherche Scientifique (CNRS) UMR 8253, Inserm UMR 1151, Paris Descartes – Sorbonne Paris Cité University, Paris, France
| | - François Machavoine
- Laboratory of Immunoregulation and Immunopathology, Institut Necker-Enfants malades, Centre National de la Recherche Scientifique (CNRS) UMR 8253, Inserm UMR 1151, Paris Descartes – Sorbonne Paris Cité University, Paris, France
| | - Rachel Rignault-Bricard
- Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, Paris Descartes – Sorbonne Paris Cité University, Imagine Institute, Inserm U1163, Paris, France
- Laboratory of Immunoregulation and Immunopathology, Institut Necker-Enfants malades, Centre National de la Recherche Scientifique (CNRS) UMR 8253, Inserm UMR 1151, Paris Descartes – Sorbonne Paris Cité University, Paris, France
| | - Valentine Brousse
- Department of General Pediatrics and Pediatric Infectious Diseases, Hôpital Necker-Enfants malades, Paris Descartes – Sorbonne Paris Cité University, Assistance Publique-Hôpitaux de Paris, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
| | - Mariane de Montalembert
- Department of General Pediatrics and Pediatric Infectious Diseases, Hôpital Necker-Enfants malades, Paris Descartes – Sorbonne Paris Cité University, Assistance Publique-Hôpitaux de Paris, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
| | - Olivier Hermine
- Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, Paris Descartes – Sorbonne Paris Cité University, Imagine Institute, Inserm U1163, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
- Department of Hematology, Hôpital Necker-Enfants malades, Paris Descartes – Sorbonne Paris Cité University, Assistance Publique-Hôpitaux de Paris, Paris, France
| | - Thiago Trovati Maciel
- Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutical Implications, Paris Descartes – Sorbonne Paris Cité University, Imagine Institute, Inserm U1163, Paris, France
- Laboratory of Excellence GR-Ex, Paris, France
| | - Maria Leite-de-Moraes
- Laboratory of Immunoregulation and Immunopathology, Institut Necker-Enfants malades, Centre National de la Recherche Scientifique (CNRS) UMR 8253, Inserm UMR 1151, Paris Descartes – Sorbonne Paris Cité University, Paris, France
- * E-mail: (SA); (MLM)
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ElAlfy MS, Adly AAM, Ebeid FSE, Eissa DS, Ismail EAR, Mohammed YH, Ahmed ME, Saad AS. Immunological role of CD4 +CD28 null T lymphocytes, natural killer cells, and interferon-gamma in pediatric patients with sickle cell disease: relation to disease severity and response to therapy. Immunol Res 2019; 66:480-490. [PMID: 29926339 DOI: 10.1007/s12026-018-9010-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Sickle cell disease (SCD) is associated with alterations in immune phenotypes. CD4+CD28null T lymphocytes have pro-inflammatory functions and are linked to vascular diseases. To assess the percentage of CD4+CD28null T lymphocytes, natural killer cells (NK), and IFN-gamma levels, we compared 40 children and adolescents with SCD with 40 healthy controls and evaluated their relation to disease severity and response to therapy. Patients with SCD steady state were studied, focusing on history of frequent vaso-occlusive crisis, hydroxyurea therapy, and IFN-gamma levels. Analysis of CD4+CD28null T lymphocytes and NK cells was done by flow cytometry. Liver and cardiac iron overload were assessed. CD4+CD28null T lymphocytes, NK cells, and IFN-gamma levels were significantly higher in patients than controls. Patients with history of frequent vaso-occlusive crisis and those with vascular complications had higher percentage of CD4+CD28null T lymphocytes and IFN-gamma while levels were significantly lower among hydroxyurea-treated patients. CD4+CD28null T lymphocytes were positively correlated to transfusional iron input while these cells and IFN-gamma were negatively correlated to cardiac T2* and duration of hydroxyurea therapy. NK cells were correlated to HbS and indirect bilirubin. Increased expression of CD4+CD28null T lymphocytes highlights their role in immune dysfunction and pathophysiology of SCD complications.
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Affiliation(s)
- Mohsen Saleh ElAlfy
- Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | | | | | - Deena Samir Eissa
- Clinical Pathology Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | | | | | - Manar Elsayed Ahmed
- Pediatrics Department, Faculty of Medicine, Ain Shams University, Cairo, Egypt
| | - Aya Sayed Saad
- Pediatrics Department, Faculty of Medicine, M.U.S.T. University, Cairo, Egypt
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Abraham AA, Lang H, Meier ER, Nickel RS, Dean M, Lawal N, Speller-Brown B, Wang Y, Kean L, Bollard CM. Characterization of natural killer cells expressing markers associated with maturity and cytotoxicity in children and young adults with sickle cell disease. Pediatr Blood Cancer 2019; 66:e27601. [PMID: 30609269 PMCID: PMC6707525 DOI: 10.1002/pbc.27601] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 11/27/2018] [Accepted: 12/17/2018] [Indexed: 01/04/2023]
Abstract
BACKGROUND Sickle cell disease (SCD) is increasingly recognized as a red blood cell disorder modulated by abnormally increased inflammation. We have previously shown that in patients with SCD not on a disease-modifying therapy (hydroxyurea or chronic transfusions), natural killer (NK) cell numbers are increased. In the current study, we further investigated the NK cell function to determine if there was evidence of increased activation and cytotoxicity. PROCEDURE We conducted a cross-sectional study of 44 patients with HbSS/HbSβ0 thalassemia at steady state (hydroxyurea = 13, chronic transfusion = 11, no disease-modifying therapy = 20) and 23 healthy controls. Using a fresh blood sample, NK immunophenotyping was performed as follows: NK cells (CD3- CD56+ lymphocytes) were evaluated for makers associated with activation (NKG2D, NKp30, NKp44, and CD69) and maturity (CD57, killer immunoglobulin-like receptors (KIR), and CD56dim). Degranulation and cytotoxicity assays were performed to evaluate NK cell function. RESULTS Patients with SCD who were not on disease-modifying therapy had a higher number of NK cells with an immunophenotype associated with increased cytotoxicity (NKG2D+ , NKp30+ , CD56dim+ , and KIR+ NK cells) compared with healthy controls and patients on hydroxyurea. NK cells from SCD patients not on disease-modifying therapy demonstrated significantly increased cytotoxicity (measured by assaying NK cell killing of the K562 cell line) compared with healthy controls (P = 0.005). Notably, NK cell cytotoxicity against K562 cells in the hydroxyurea or chronic transfusion patients was not significantly different from that in healthy controls. CONCLUSION SCD is associated with increased NK cell function as well as increased NK cell numbers, which appears to be normalized with disease-modifying therapy.
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Affiliation(s)
| | - Haili Lang
- Children’s National Health System, Washington, DC
| | | | | | - Marcus Dean
- Children’s National Health System, Washington, DC
| | - Nurah Lawal
- Children’s National Health System, Washington, DC
| | | | - Yunfei Wang
- Children’s National Health System, Washington, DC
| | - Leslie Kean
- Seattle Children’s Hospital, Seattle, Washington
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Telen MJ, Malik P, Vercellotti GM. Therapeutic strategies for sickle cell disease: towards a multi-agent approach. Nat Rev Drug Discov 2019; 18:139-158. [PMID: 30514970 PMCID: PMC6645400 DOI: 10.1038/s41573-018-0003-2] [Citation(s) in RCA: 111] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
For over 100 years, clinicians and scientists have been unravelling the consequences of the A to T substitution in the β-globin gene that produces haemoglobin S, which leads to the systemic manifestations of sickle cell disease (SCD), including vaso-occlusion, anaemia, haemolysis, organ injury and pain. However, despite growing understanding of the mechanisms of haemoglobin S polymerization and its effects on red blood cells, only two therapies for SCD - hydroxyurea and L-glutamine - are approved by the US Food and Drug Administration. Moreover, these treatment options do not fully address the manifestations of SCD, which arise from a complex network of interdependent pathophysiological processes. In this article, we review efforts to develop new drugs targeting these processes, including agents that reactivate fetal haemoglobin, anti-sickling agents, anti-adhesion agents, modulators of ischaemia-reperfusion and oxidative stress, agents that counteract free haemoglobin and haem, anti-inflammatory agents, anti-thrombotic agents and anti-platelet agents. We also discuss gene therapy, which holds promise of a cure, although its widespread application is currently limited by technical challenges and the expense of treatment. We thus propose that developing systems-oriented multi-agent strategies on the basis of SCD pathophysiology is needed to improve the quality of life and survival of people with SCD.
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Affiliation(s)
- Marilyn J Telen
- Division of Hematology, Department of Medicine and Duke Comprehensive Sickle Cell Center, Duke University, Durham, NC, USA.
| | - Punam Malik
- Division of Experimental Hematology and Cancer Biology and the Division of Hematology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Gregory M Vercellotti
- Division of Hematology, Oncology and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, MN, USA
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Atmış B, Kılınç Y, Yılmaz M, Atmış A, Karagün BŞ, Şaşmaz Hİ. Orak hücreli anemi hastalarında T helper, T sitotoksik ve doğal öldürücü hücre profili ve klinik prognozla ilişkisi. CUKUROVA MEDICAL JOURNAL 2018. [DOI: 10.17826/cumj.408559] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Moerdler S, Manwani D. New insights into the pathophysiology and development of novel therapies for sickle cell disease. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2018; 2018:493-506. [PMID: 30504350 PMCID: PMC6245971 DOI: 10.1182/asheducation-2018.1.493] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Although the seminal event in sickle cell disease is the polymerization of abnormal hemoglobin, the downstream pathophysiology of vasoocclusion results from heterotypic interactions between the altered, adhesive sickle cell red blood cells, neutrophils, endothelium, and platelets. Ischemia reperfusion injury, hemolysis, and oxidant damage all contribute to heightened inflammation and activation of the hemostatic system. These various pathways are the focus of emerging treatments with potential to ameliorate disease manifestations. This review summarizes the considerable progress in development of these agents despite challenges in selection of study end points and complex pathophysiology.
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Affiliation(s)
- Scott Moerdler
- Children’s Hospital, Montefiore Medical Center, Bronx, NY; and
- Department of Microbiology and Immunology and
| | - Deepa Manwani
- Children’s Hospital, Montefiore Medical Center, Bronx, NY; and
- Division of Pediatric Hematology, Oncology, Marrow and Blood Cell Transplantation, Albert Einstein College of Medicine, Bronx, NY
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25
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Yu JC, Lin G, Field JJ, Linden J. Induction of antiinflammatory purinergic signaling in activated human iNKT cells. JCI Insight 2018; 3:91954. [PMID: 30185656 DOI: 10.1172/jci.insight.91954] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 07/31/2018] [Indexed: 12/21/2022] Open
Abstract
Invariant natural killer T (iNKT) cells are activated at sites of local tissue injury, or globally during vaso-occlusive episodes of sickle cell disease (SCD). Tissue damage stimulates production of CD1d-restricted lipid antigens that activate iNKT cells to produce Th1- and Th2-type cytokines. Here, we show that circulating iNKT cells in SCD patients express elevated levels of the ectonucleoside triphosphate diphosphosphohydrolase, CD39, as well the adenosine A2A receptor (A2AR). We also investigated the effects of stimulating cultured human iNKT cells on the expression of genes involved in the regulation of purinergic signaling. iNKT cell stimulation caused induction of ADORA2A, P2RX7, CD38, CD39, ENPP1, CD73, PANX1, and ENT1. Transcription of ADA, which degrades adenosine, was reduced. Induction of CD39 mRNA was associated with increased ecto-ATPase activity on iNKT cells that was blocked by POM1. Exposure of iNKT cells to A2AR agonists during stimulation reduced production of IFN-γ and enhanced production of IL-13 and CD39. Based on these findings, we define "purinergic Th2-type cytokine bias" as an antiinflammatory purinergic response to iNKT cell stimulation resulting from changes in the transcription of several genes involved in purine release, extracellular metabolism, and signaling.
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Affiliation(s)
- Jennifer C Yu
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology La Jolla, California, USA.,Division of Pediatric Hematology/Oncology, University of California/Rady Children's Hospital, San Diego, California, USA
| | - Gene Lin
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology La Jolla, California, USA
| | - Joshua J Field
- BloodCenter of Wisconsin, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Joel Linden
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology La Jolla, California, USA.,Department of Pharmacology, University of California San Diego, San Diego, California, USA
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26
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Shet AS, Thein SL. Therapeutic advances in sickle cell disease in the last decade. Indian J Med Res 2018; 145:708-712. [PMID: 29067969 PMCID: PMC5674537 DOI: 10.4103/ijmr.ijmr_1153_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Affiliation(s)
- Arun S Shet
- Sickle Cell Branch, National Heart, Lung & Blood Institute, The National Institutes of Health, Bethesda, MD 20892-1589, USA
| | - Swee Lay Thein
- Sickle Cell Branch, National Heart, Lung & Blood Institute, The National Institutes of Health, Bethesda, MD 20892-1589, USA
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Abstract
We have entered an era of exploding interest in therapeutics for sickle cell disease. The expansion in our understanding of sickle cell disease pathophysiology has enhanced the range of potential therapeutic targets. From induction of fetal hemoglobin to antiadhesion molecules, we are potentially on the cusp of making life-altering modifications for individuals with sickle cell disease. This disease population cannot afford to let the current momentum wane. Studies exploring combinations of therapies affecting multiple steps in the pathophysiology and exploring novel and clinically relevant outcomes are incumbent.
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Abstract
Introduction Sickle cell disease (SCD) is an orphan disease in the United States, but is highly prevalent worldwide. Only two drugs, hydroxyurea and L-glutamine, are approved for this disease. With an improved understanding of the pathophysiology of SCD as well as the success of several recently approved drugs for other orphan diseases, there is an increased interest in the development of drugs for SCD. Areas covered This review summarizes published studies of drug therapies and ongoing trials of novel agents. Expert opinion The development of drugs with different mechanisms of action offers opportunities for combination and individualized therapy in SCD. In addition to acute pain crisis, the evaluation of other SCD-related complications, exercise capacity, patient reported outcomes and validated surrogate endpoints are necessary to advance drug development. It is important to involve sites in sub-Saharan Africa and India, which have the highest burden of SCD, in trials of novel therapies.
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Affiliation(s)
- Kenneth I Ataga
- Division of Hematology/Oncology, University of North Carolina, Chapel Hill, NC
| | - Payal C Desai
- Division of Hematology/Oncology, University of North Carolina, Chapel Hill, NC.,#Division of Hematology, The Ohio State University, Columbus, OH
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29
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Morrone K, Mitchell WB, Manwani D. Novel Sickle Cell Disease Therapies: Targeting Pathways Downstream of Sickling. Semin Hematol 2018; 55:68-75. [PMID: 30616808 DOI: 10.1053/j.seminhematol.2018.04.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 04/13/2018] [Indexed: 12/15/2022]
Abstract
Sickle cell disease is an inherited hemoglobinopathy characterized by hemolytic anemia, frequent painful episodes, poor quality of life, end organ damage and a shortened lifespan. Although the seminal event is the polymerization of the abnormal hemoglobin, the downstream pathophysiology of vaso-occlusion results from heterotypic interactions between the altered, adhesive sickle cell RBCs, neutrophils, endothelium, and platelets. Ischemia reperfusion injury, hemolysis and oxidant damage all contribute to heightened inflammation and activation of the hemostatic system. These downstream targets are the focus of emerging treatments with considerable potential to ameliorate disease manifestations. This review summarizes the progress on development of these agents.
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Affiliation(s)
- Kerry Morrone
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Albert Einstein College of Medicine, Children's Hospital at Montefiore, Bronx, NY
| | - William Beau Mitchell
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Icahn School of Medicine at Mount Sinai, Kravis Children's Hospital, New York, NY
| | - Deepa Manwani
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Albert Einstein College of Medicine, Children's Hospital at Montefiore, Bronx, NY.
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30
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De A, Manwani D, Rastogi D. Airway inflammation in sickle cell disease-A translational perspective. Pediatr Pulmonol 2018; 53:400-411. [PMID: 29314737 DOI: 10.1002/ppul.23932] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 11/29/2017] [Indexed: 12/14/2022]
Abstract
Asthma and sickle cell disease (SCD) are common chronic conditions in children of African ancestry that are characterized by cough, wheeze, and obstructive patterns on pulmonary function. Pulmonary function testing in children with SCD has estimated a prevalence of obstructive lung disease ranging from 13% to 57%, and airway hyper-responsiveness of up to 77%, independent of a diagnosis of asthma. Asthma co-existing with SCD is associated with increased risk of acute chest syndrome (ACS), respiratory symptoms, pain episodes, and death. However, there are inherent differences in the pathophysiology of SCD and asthma. While classic allergic asthma in the general population is associated with a T-helper 2 cell (Th-2 cells) pattern of cell inflammation, increased IgE levels and often positive allergy testing, inflammation in SCD is associated with different inflammatory pathways, involving neutrophilic and monocytic pathways, which have been explored to a limited extent in mouse models and with a dearth of human studies. The current review summarizes the existent literature on sickle cell related airway inflammation and its cross roads with allergic asthma-related inflammation, and discusses the importance of further elucidating and understanding these common and divergent inflammatory pathways in human studies to facilitate development of targeted therapy for children with SCD and pulmonary morbidity.
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Affiliation(s)
- Aliva De
- Division of Respiratory and Sleep Medicine, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York
| | - Deepa Manwani
- Division of Hematology/Oncology, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York
| | - Deepa Rastogi
- Division of Respiratory and Sleep Medicine, The Children's Hospital at Montefiore, Albert Einstein College of Medicine, Bronx, New York
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Randomized phase 2 trial of regadenoson for treatment of acute vaso-occlusive crises in sickle cell disease. Blood Adv 2017; 1:1645-1649. [PMID: 29296811 DOI: 10.1182/bloodadvances.2017009613] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 07/23/2017] [Indexed: 12/21/2022] Open
Abstract
Adenosine A2A receptor (A2AR) agonists have been shown to decrease tissue inflammation induced by hypoxia/reoxygenation in mice with sickle cell disease (SCD). The key mediator of the A2AR agonist's anti-inflammatory effects is a minor lymphocyte subset, invariant natural killer T (iNKT) cells. We tested the hypothesis that administration of an A2AR agonist in patients with SCD would decrease iNKT cell activation and dampen the severity of vaso-occlusive (VO) crises. In a phase 2, randomized, placebo-controlled trial, we administered a 48-hour infusion of the A2AR agonist regadenoson (1.44 μg/kg per hour) to patients with SCD during VO crises to produce a plasma concentration of ∼5 nM, a concentration known from prior studies to suppress iNKT cell activation in SCD. The primary outcome measure was a >30% reduction in the percentage of activated iNKT cells. Ninety-two patients with SCD were randomized to receive a 48-hour infusion of regadenoson or placebo, in addition to standard-of-care treatment, during hospital admission for a VO crisis and had analyzable iNKT cell samples. The proportion of subjects who demonstrated a reduction of >30% in activated iNKT cells was not significantly different between the regadenoson and placebo arms (43% vs 23%; P = .07). There were also no differences between regadenoson and placebo groups in length of hospital stay, mean total opioid use, or pain scores. These data demonstrate that a low-dose infusion of regadenoson intended to reduce the activity of iNKT cells is not sufficient to produce a statistically significant reduction in such activation or in measures of clinical efficacy. This trial was registered at www.clinicaltrials.gov as #NCT01788631.
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32
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Ware RE, de Montalembert M, Tshilolo L, Abboud MR. Sickle cell disease. Lancet 2017; 390:311-323. [PMID: 28159390 DOI: 10.1016/s0140-6736(17)30193-9] [Citation(s) in RCA: 560] [Impact Index Per Article: 80.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 11/11/2016] [Accepted: 11/18/2016] [Indexed: 01/08/2023]
Abstract
Sickle cell disease is a common and life-threatening haematological disorder that affects millions of people worldwide. Abnormal sickle-shaped erythrocytes disrupt blood flow in small vessels, and this vaso-occlusion leads to distal tissue ischaemia and inflammation, with symptoms defining the acute painful sickle-cell crisis. Repeated sickling and ongoing haemolytic anaemia, even when subclinical, lead to parenchymal injury and chronic organ damage, causing substantial morbidity and early mortality. Currently available treatments are limited to transfusions and hydroxycarbamide, although stem cell transplantation might be a potentially curative therapy. Several new therapeutic options are in development, including gene therapy and gene editing. Recent advances include systematic universal screening for stroke risk, improved management of iron overload using oral chelators and non-invasive MRI measurements, and point-of-care diagnostic devices. Controversies include the role of haemolysis in sickle cell disease pathophysiology, optimal management of pregnancy, and strategies to prevent cerebrovascular disease.
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Affiliation(s)
- Russell E Ware
- Division of Hematology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
| | | | - Léon Tshilolo
- Centre Hospitalier Monkole, Kinshasa, Democratic Republic of Congo
| | - Miguel R Abboud
- Department of Pediatrics, American University of Beirut, Beirut, Lebanon
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Adenosine A1 and A2A Receptors in the Brain: Current Research and Their Role in Neurodegeneration. Molecules 2017; 22:molecules22040676. [PMID: 28441750 PMCID: PMC6154612 DOI: 10.3390/molecules22040676] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 04/21/2017] [Accepted: 04/21/2017] [Indexed: 12/20/2022] Open
Abstract
The inhibitory adenosine A1 receptor (A1R) and excitatory A2A receptor (A2AR) are predominantly expressed in the brain. Whereas the A2AR has been implicated in normal aging and enhancing neurotoxicity in multiple neurodegenerative diseases, the inhibitory A1R has traditionally been ascribed to have a neuroprotective function in various brain insults. This review provides a summary of the emerging role of prolonged A1R signaling and its potential cross-talk with A2AR in the cellular basis for increased neurotoxicity in neurodegenerative disorders. This A1R signaling enhances A2AR-mediated neurodegeneration, and provides a platform for future development of neuroprotective agents in stroke, Parkinson’s disease and epilepsy.
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Abstract
BACKGROUND Sickle cell disease is an autosomal recessive inherited haemoglobinopathy which causes painful vaso-occlusive crises due to sickle red blood cell dehydration. Vaso-occlusive crises are common painful events responsible for a variety of clinical complications; overall mortality is increased and life expectancy decreased compared to the general population. Experimental studies suggest that intravenous magnesium has proven to be well-tolerated in individuals hospitalised for the immediate relief of acute (sudden onset) painful crisis and has the potential to decrease the length of hospital stay. Some in vitro studies and open studies of long-term oral magnesium showed promising effect on pain relief but failed to show its efficacy. The studies show that oral magnesium therapy may prevent sickle red blood cell dehydration and prevent recurrent painful episodes. There is a need to access evidence for the impact of oral and intravenous magnesium effect on frequency of pain, length of hospital stay and quality of life. OBJECTIVES To evaluate the effects of short-term intravenous magnesium on the length of hospital stay and quality of life in children and adults with sickle cell disease. To determine the effects of long-term oral magnesium therapy on the frequency of painful crises and the quality of life in children and adults with sickle cell disease. SEARCH METHODS We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books.Date of last search of the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register: 01 December 2016.Date of last search of other resources (clinical trials registries): 29 March 2017. SELECTION CRITERIA We searched for published and unpublished randomized controlled studies of oral or intravenous magnesium compared to placebo or no magnesium. DATA COLLECTION AND ANALYSIS Authors independently assessed the study quality and extracted the data using standard Cochrane methodologies. MAIN RESULTS We included five randomized placebo-controlled studies with a total of 386 participants (aged three to 53 years). Two shorter parallel studies (n = 306) compared intravenous magnesium sulphate to placebo (normal saline) for admission to hospital due to a vaso-occlusive crisis, for which we were able to analyse data. The quality of evidence was moderate for studies presenting this comparison mainly due to limitations due to risk of bias and imprecision. Two of the three longer-term studies comparing oral magnesium pidolate to placebo had a cross-over design. The third was a parallel factorial study which compared hydroxyurea and oral magnesium to each other and to placebo over a longer period of time; we only present the comparison of oral magnesium to placebo from this study. The quality of evidence was very low with uncertainty of the estimation.The eight-hourly dose levels in the two studies of intravenous magnesium were different; one used 100 mg/kg while the second used 40 mg/kg. Only one of these studies (n = 104) reported the mean daily pain score while hospitalised (a non-significant difference between groups, moderate quality evidence). The second study (n = 202) reported a number of child- and parent-reported quality of life scores. None of the scores showed any difference between treatment groups (low quality evidence). Data from one study (n = 106) showed no difference in length of stay in hospital between groups (low quality evidence). Both studies reported on adverse events, but not defined by severity as we had planned. One study showed significantly more participants receiving intravenous magnesium experienced warmth at infusion site compared to placebo; there were no differences between groups for other adverse events (low quality evidence).Three studies (n = 80) compared oral magnesium pidolate to placebo. None of them reported data which we were able to analyse. One study (n = 24) reported on the number of painful days and stated there was no difference between two groups (low quality evidence). None of the studies reported on quality of life or length of hospital stay. Two studies (n = 68) reported there were no differences in levels of magnesium in either plasma or red blood cells (moderate quality evidence). Two studies (n = 56) reported adverse events. One reported episodes of mild diarrhoea and headache, all of which resolved without stopping treatment. The second study reported adverse events as gastrointestinal disorders, headache or migraine, upper respiratory infections and rash; which were all evenly distributed across treatment groups (moderate quality evidence). AUTHORS' CONCLUSIONS Moderate to low quality evidence showed neither intravenous magnesium and oral magnesium therapy has an effect on reducing painful crisis, length of hospital stay and changing quality of life in treating sickle cell disease. Therefore, no definitive conclusions can be made regarding its clinical benefit. Further randomized controlled studies, perhaps multicentre, are necessary to establish whether intravenous and oral magnesium therapies have any effect on improving the health of people with sickle cell disease.
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Affiliation(s)
- Nan Nitra Than
- Melaka‐Manipal Medical CollegeDepartment of Community MedicineJalan Batu HamparBukit BaruMelakaMalaysia75150
| | - Htoo Htoo Kyaw Soe
- Melaka‐Manipal Medical CollegeDepartment of Community MedicineJalan Batu HamparBukit BaruMelakaMalaysia75150
| | - Senthil K Palaniappan
- NHS trustDepartment of Medicine, University Hospitals of LeicesterLeicester Royal InfirmaryLeicesterUKLE1 5WW
| | - Adinegara BL Abas
- Melaka‐Manipal Medical CollegeDepartment of Community MedicineJalan Batu HamparBukit BaruMelakaMalaysia75150
| | - Lucia De Franceschi
- University of Verona‐AOUI VeronaDepartment of MedicinePolilinico GB RossiVeronaItaly37134
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Jackson S, George RT, Lodge MA, Piotrowski A, Wahl RL, Gujar SK, Grossman SA. The effect of regadenoson on the integrity of the human blood-brain barrier, a pilot study. J Neurooncol 2017; 132:513-519. [PMID: 28315063 DOI: 10.1007/s11060-017-2404-1] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 03/12/2017] [Indexed: 10/19/2022]
Abstract
Regadenoson is an FDA approved adenosine receptor agonist which increases blood-brain barrier (BBB) permeability in rodents. Regadenoson is used clinically for pharmacologic cardiac stress testing using SPECT or CT imaging agents that do not cross an intact BBB. This study was conducted to determine if standard doses of regadenoson transiently disrupt the human BBB allowing higher concentrations of systemically administered imaging agents to enter the brain. Patients without known intracranial disease undergoing clinically indicated pharmacologic cardiac stress tests were eligible for this study. They received regadenoson (0.4 mg) followed by brain imaging with either 99mTc-sestamibi for SPECT or visipaque for CT imaging. Pre- and post-regadenoson penetration of imaging agents into brain were quantified [SPECT: radioactive counts, CT: Hounsfield units (HU)] and compared using a matched-pairs t-test. Twelve patients (33% male, median 60 yo) were accrued: 7 SPECT and 5 CT. No significant differences were noted in pre- and post-regadenoson values using mean radionuclide counts (726 vs. 757) or HU (29 vs. 30). While animal studies have demonstrated that regadenoson transiently increases the permeability of the BBB to dextran and temozolomide, we were unable to document changes in the penetration of contrast agents in humans with intact BBB using the FDA approved doses of regadenoson for cardiac evaluation. Further studies are needed exploring alternate regadenoson dosing, schedules, and studies in patients with brain tumors; as transiently disrupting the BBB to improve drug entry into the brain is critical to improving the care of patients with CNS malignancies.
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Affiliation(s)
- Sadhana Jackson
- Brain Cancer Program, Johns Hopkins University, David H. Koch Cancer Research Building II, 1550 Orleans Street, Room 1M16, Baltimore, MD, 21287, USA
| | - Richard T George
- Heart and Vascular Institute, Johns Hopkins University, 600 N. Wolfe Street, Sheikh Zayed Tower, Baltimore, MD, 21287, USA
| | - Martin A Lodge
- Nuclear Medicine, Russell H. Morgan Dept. of Radiology and Radiological Sciences, Johns Hopkins University, 601 Caroline St, Baltimore, MD, 21231, USA
| | - Anna Piotrowski
- Brain Cancer Program, Johns Hopkins University, David H. Koch Cancer Research Building II, 1550 Orleans Street, Room 1M16, Baltimore, MD, 21287, USA
| | - Richard L Wahl
- Nuclear Medicine, Russell H. Morgan Dept. of Radiology and Radiological Sciences, Johns Hopkins University, 601 Caroline St, Baltimore, MD, 21231, USA.,Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 South Kingshighway Blvd., St. Louis, MO, 63110, USA
| | - Sachin K Gujar
- Radiology and Radiological Science, Johns Hopkins University, 600 N. Wolfe Street, Sheikh Zayed Tower, Baltimore, MD, 21287, USA
| | - Stuart A Grossman
- Brain Cancer Program, Johns Hopkins University, David H. Koch Cancer Research Building II, 1550 Orleans Street, Room 1M16, Baltimore, MD, 21287, USA.
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36
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Cannas G, Poutrel S, Thomas X. Hydroxycarbamine: from an Old Drug Used in Malignant Hemopathies to a Current Standard in Sickle Cell Disease. Mediterr J Hematol Infect Dis 2017; 9:e2017015. [PMID: 28293403 PMCID: PMC5333733 DOI: 10.4084/mjhid.2017.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 01/20/2017] [Indexed: 01/31/2023] Open
Abstract
While hydroxycarbamide (hydroxyurea, HU) has less and fewer indications in malignant hemopathies, it represents the only widely used drug which modifies sickle cell disease pathogenesis. Clinical experience with HU for patients with sickle cell disease has been accumulated over the past 25 years in Western countries. The review of the literature provides increasing support for safety and efficacy in both children and adults for reducing acute vaso-occlusive events including pain episodes and acute chest syndrome. No increased incidence of leukemia and teratogenicity was demonstrated. HU has become the standard-of-care for sickle cell anemia but remains underused. Barriers to its use should be identified and overcome.
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Affiliation(s)
- Giovanna Cannas
- Hospices Civils de Lyon, Department of Internal Medicine, Edouard Herriot Hospital, Lyon, France
- Claude Bernard University Lyon 1, Laboratoire Interuniversitaire de Biologie de la Motricité EA7424, Equipe ‘Vascular biology and red blood cell’, Villeurbanne, France
| | - Solène Poutrel
- Hospices Civils de Lyon, Department of Internal Medicine, Edouard Herriot Hospital, Lyon, France
| | - Xavier Thomas
- Hospices Civils de Lyon, Hematology Department, Lyon-Sud Hospital, Pierre Bénite, France
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37
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Field JJ, Majerus E, Ataga KI, Vichinsky EP, Schaub R, Mashal R, Nathan DG. NNKTT120, an anti-iNKT cell monoclonal antibody, produces rapid and sustained iNKT cell depletion in adults with sickle cell disease. PLoS One 2017; 12:e0171067. [PMID: 28152086 PMCID: PMC5289534 DOI: 10.1371/journal.pone.0171067] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Accepted: 01/13/2017] [Indexed: 02/07/2023] Open
Abstract
Invariant NKT (iNKT) cells can be activated to stimulate a broad inflammatory response. In murine models of sickle cell disease (SCD), interruption of iNKT cell activity prevents tissue injury from vaso-occlusion. NKTT120 is an anti-iNKT cell monoclonal antibody that has the potential to rapidly and specifically deplete iNKT cells and, potentially, prevent vaso-occlusion. We conducted an open-label, multi-center, single-ascending-dose study of NKTT120 to determine its pharmacokinetics, pharmacodynamics and safety in steady-state patients with SCD. Doses were escalated in a 3+3 study design over a range from 0.001 mg/kg to 1.0 mg/kg. Twenty-one adults with SCD were administered NKTT120 as part of 7 dose cohorts. Plasma levels of NKTT120 predictably increased with higher doses. Median half-life of NKTT120 was 263 hours. All subjects in the higher dose cohorts (0.1 mg/kg, 0.3 mg/kg, and 1 mg/kg) demonstrated decreased iNKT cells below the lower limit of quantification within 6 hours after infusion, the earliest time point at which they were measured. In those subjects who received the two highest doses of NKTT120 (0.3, 1 mg/kg), iNKT cells were not detectable in the peripheral blood for a range of 2 to 5 months. There were no serious adverse events in the study deemed to be related to NKTT120. In adults with SCD, NKTT120 produced rapid, specific and sustained iNKT cell depletion without any infusional toxicity or attributed serious adverse events. The next step is a trial to determine NKTT120’s ability to decrease rate of vaso-occlusive pain episodes. Trial Registration: clinicaltrials.gov NCT01783691.
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Affiliation(s)
- Joshua J. Field
- Medical Sciences Institute, Blood Center of Wisconsin, Milwaukee, Wisconsin, United States of America
- Department of Medicine, Medical College of Wisconsin, Milwaukee, Wisconsin, United States of America
- * E-mail:
| | - Elaine Majerus
- Department of Medicine, Washington University in St. Louis, St. Louis, Missouri, United States of America
| | - Kenneth I. Ataga
- University of North Carolina, Chapel Hill, North Carolina, United States of America
| | | | - Robert Schaub
- NKT Therapeutics, Waltham, Massachusetts, United States of America
| | - Robert Mashal
- NKT Therapeutics, Waltham, Massachusetts, United States of America
| | - David G. Nathan
- Dana-Farber Cancer Institute, Boston, Massachusetts, United States of America
- Boston Children’s Hospital, Boston, Massachusetts, United States of America
- Harvard Medical School, Boston, Massachusetts, United States of America
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38
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39
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Meier ER, Rampersad A. Pediatric sickle cell disease: past successes and future challenges. Pediatr Res 2017; 81:249-258. [PMID: 27706129 DOI: 10.1038/pr.2016.204] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Accepted: 09/30/2016] [Indexed: 02/06/2023]
Abstract
Once a fatal disease of childhood, more than 95% of patients born today with sickle cell disease (SCD) in developed countries are expected to survive into adulthood, largely because of improvements in supportive and preventive care (newborn screening, penicillin prophylaxis, transcranial Doppler (TCD) screening). Hydroxyurea (HU) therapy, the only oral medication currently available to prevent SCD complications, has become more widespread over the past 20 y. The NHLBI recommends that HU be offered to all patients with HbSS beginning at 9 mo of age, and the recently published Abnormal TCD with Transfusions Changing to HU (TWiTCH) trial has shown HU as an acceptable alternative to transfusion therapy for patients at high risk of stroke. While hematopoietic stem cell transplant (HSCT) is a curative option for SCD, less than 25% of patients have a suitable donor. Alternative stem cell sources from unrelated donors and haplo-identical donors are currently under investigation as are gene therapy trials. This review will focus on early efforts to elucidate SCD pathophysiology as well as supportive and preventive care improvements. Findings from recent multi-center studies (Silent Infarct Transfusion (SIT) Trial and TWiTCH) will be summarized. Finally, HSCT trials and gene therapy will be reviewed.
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Affiliation(s)
- Emily Riehm Meier
- Pediatric Hematology, Indiana Hemophilia and Thrombosis Center, Indianapolis, Indiana
| | - Angeli Rampersad
- Pediatric Hematology, Indiana Hemophilia and Thrombosis Center, Indianapolis, Indiana
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40
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Alapan Y, Fraiwan A, Kucukal E, Hasan MN, Ung R, Kim M, Odame I, Little JA, Gurkan UA. Emerging point-of-care technologies for sickle cell disease screening and monitoring. Expert Rev Med Devices 2016; 13:1073-1093. [PMID: 27785945 PMCID: PMC5166583 DOI: 10.1080/17434440.2016.1254038] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
INTRODUCTION Sickle Cell Disease (SCD) affects 100,000 Americans and more than 14 million people globally, mostly in economically disadvantaged populations, and requires early diagnosis after birth and constant monitoring throughout the life-span of the patient. Areas covered: Early diagnosis of SCD still remains a challenge in preventing childhood mortality in the developing world due to requirements of skilled personnel and high-cost of currently available modalities. On the other hand, SCD monitoring presents insurmountable challenges due to heterogeneities among patient populations, as well as in the same individual longitudinally. Here, we describe emerging point-of-care micro/nano platform technologies for SCD screening and monitoring, and critically discuss current state of the art, potential challenges associated with these technologies, and future directions. Expert commentary: Recently developed microtechnologies offer simple, rapid, and affordable screening of SCD and have the potential to facilitate universal screening in resource-limited settings and developing countries. On the other hand, monitoring of SCD is more complicated compared to diagnosis and requires comprehensive validation of efficacy. Early use of novel microdevices for patient monitoring might come in especially handy in new clinical trial designs of emerging therapies.
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Affiliation(s)
- Yunus Alapan
- Case Biomanufacturing and Microfabrication Laboratory, Mechanical and Aerospace Engineering Department, Case Western Reserve University, Cleveland, OH, USA
| | - Arwa Fraiwan
- Case Biomanufacturing and Microfabrication Laboratory, Mechanical and Aerospace Engineering Department, Case Western Reserve University, Cleveland, OH, USA
| | - Erdem Kucukal
- Case Biomanufacturing and Microfabrication Laboratory, Mechanical and Aerospace Engineering Department, Case Western Reserve University, Cleveland, OH, USA
| | - M. Noman Hasan
- Case Biomanufacturing and Microfabrication Laboratory, Mechanical and Aerospace Engineering Department, Case Western Reserve University, Cleveland, OH, USA
| | - Ryan Ung
- Biomedical Engineering Department, Case Western Reserve University, Cleveland, OH, USA
| | - Myeongseop Kim
- Case Biomanufacturing and Microfabrication Laboratory, Mechanical and Aerospace Engineering Department, Case Western Reserve University, Cleveland, OH, USA
| | - Isaac Odame
- Division of Haematology/Oncology, The Hospital for Sick Children; Toronto, Canada
- Department of Pediatrics, Faculty of Medicine, University of Toronto, Toronto, Canada
| | - Jane A. Little
- Department of Hematology and Oncology, School of Medicine, Case Western Reserve University, Cleveland, OH, USA
- Seidman Cancer Center at University Hospitals, Case Medical Center, Cleveland, OH, USA
| | - Umut A. Gurkan
- Case Biomanufacturing and Microfabrication Laboratory, Mechanical and Aerospace Engineering Department, Case Western Reserve University, Cleveland, OH, USA
- Biomedical Engineering Department, Case Western Reserve University, Cleveland, OH, USA
- Department of Orthopedics, Case Western Reserve University, Cleveland, OH, USA
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41
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Telen MJ. Developing new pharmacotherapeutic approaches to treating sickle-cell disease. ACTA ACUST UNITED AC 2016; 12:239-247. [PMID: 28484512 DOI: 10.1111/voxs.12305] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Survival for patients with SCD has been prolonged by improvements in supportive care, including vaccinations, antibiotic prophylaxis, and overall medical management, including tra nsfusion. However, there remains only one approved, partially effective drug for sickle cell disease-hydroxyurea (hydroxycarbamide). The world desperately needs better ways of both treating and preventing the recurrent painful vaso-occlusive episodes pathognomonic of sickle cell disease as well as the end-organ damage that still leads inexorably to severely shortened life expectancies throughout the world. Based on accumulating knowledge about how the abnormal red blood cells of sickle cell disease cause the double scourge of acute painful episodes and progressive end-organ damage, both pharmaceutical enterprises and individual investigators are now pursuing multiple new avenues for treating sickle cell disease. As a result, many compounds are in active development, both in preclinical models as well as in phase I, II, and III clinical trials. These agents target many pathophysiologic processes thought to be critical in sickle cell disease, including the chemical and physical behavior of haemoglobin S, cell adhesion, coagulation pathways, platelet activation, inflammatory pathways, and upregulation of haemoglobin F expression. In addition, recent explorations of the genetic variations that predispose to certain types of sickle cell disease-related tissue injury, such as stroke or nephropathy, are expected to lead to identification of drugs targeting the pathways uncovered by such work. Thus, the next five to ten years holds a promise of new treatments for sickle cell disease.
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Affiliation(s)
- Marilyn J Telen
- Division of Hematology, Department of Medicine, Duke Comprehensive Sickle Cell Center, Duke University, Durham, NC, USA, Box 2615 DUMC, Durham, NC 27710, TEL: +1 919 684 5378, FAX: +1 919 681 7688,
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Hothersall JD, Guo D, Sarda S, Sheppard RJ, Chen H, Keur W, Waring MJ, IJzerman AP, Hill SJ, Dale IL, Rawlins PB. Structure-Activity Relationships of the Sustained Effects of Adenosine A2A Receptor Agonists Driven by Slow Dissociation Kinetics. Mol Pharmacol 2016; 91:25-38. [PMID: 27803241 PMCID: PMC5198511 DOI: 10.1124/mol.116.105551] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2016] [Accepted: 10/28/2016] [Indexed: 12/02/2022] Open
Abstract
The duration of action of adenosine A2A receptor (A2A) agonists is critical for their clinical efficacy, and we sought to better understand how this can be optimized. The in vitro temporal response profiles of a panel of A2A agonists were studied using cAMP assays in recombinantly (CHO) and endogenously (SH-SY5Y) expressing cells. Some agonists (e.g., 3cd; UK-432,097) but not others (e.g., 3ac; CGS-21680) demonstrated sustained wash-resistant agonism, where residual receptor activation continued after washout. The ability of an antagonist to reverse pre-established agonist responses was used as a surrogate read-out for agonist dissociation kinetics, and together with radioligand binding studies suggested a role for slow off-rate in driving sustained effects. One compound, 3ch, showed particularly marked sustained effects, with a reversal t1/2 > 6 hours and close to maximal effects that remained for at least 5 hours after washing. Based on the structure-activity relationship of these compounds, we suggest that lipophilic N6 and bulky C2 substituents can promote stable and long-lived binding events leading to sustained agonist responses, although a high compound logD is not necessary. This provides new insight into the binding interactions of these ligands and we anticipate that this information could facilitate the rational design of novel long-acting A2A agonists with improved clinical efficacy.
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Affiliation(s)
- J Daniel Hothersall
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Dong Guo
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Sunil Sarda
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Robert J Sheppard
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Hongming Chen
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Wesley Keur
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Michael J Waring
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Adriaan P IJzerman
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Stephen J Hill
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Ian L Dale
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
| | - Philip B Rawlins
- AstraZeneca, Discovery Sciences, Alderley Park, United Kingdom (J.D.H., S.S.); AstraZeneca, Oncology, Cambridge, United Kingdom (R.J.S.); AstraZeneca, Discovery Sciences, Mölndal, Sweden (H.C.); AstraZeneca, Discovery Sciences, Cambridge Science Park, United Kingdom (I.L.D., P.B.R.); AstraZeneca, Oncology, Alderley Park, United Kingdom (M.J.W.); Leiden Academic Centre for Drug Research, Division of Medicinal Chemistry, The Netherlands (D.G., W.K., A.P.I.J.); and University of Nottingham, School of Life Sciences, United Kingdom (S.J.H.)
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Jacobson KA, Civan MM. Ocular Purine Receptors as Drug Targets in the Eye. J Ocul Pharmacol Ther 2016; 32:534-547. [PMID: 27574786 PMCID: PMC5069731 DOI: 10.1089/jop.2016.0090] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 07/13/2016] [Indexed: 02/06/2023] Open
Abstract
Agonists and antagonists of various subtypes of G protein coupled adenosine receptors (ARs), P2Y receptors (P2YRs), and ATP-gated P2X receptor ion channels (P2XRs) are under consideration as agents for the treatment of ocular diseases, including glaucoma and dry eye. Numerous nucleoside and nonnucleoside modulators of the receptors are available as research tools and potential therapeutic molecules. Three of the 4 subtypes of ARs have been exploited with clinical candidate molecules for treatment of the eye: A1, A2A, and A3. An A1AR agonist is in clinical trials for glaucoma, A2AAR reduces neuroinflammation, A3AR protects retinal ganglion cells from apoptosis, and both A3AR agonists and antagonists had been reported to lower intraocular pressure (IOP). Extracellular concentrations of endogenous nucleotides, including dinucleoside polyphosphates, are increased in pathological states, activating P2Y and P2XRs throughout the eye. P2YR agonists, including P2Y2 and P2Y6, lower IOP. Antagonists of the P2X7R prevent the ATP-induced neuronal apoptosis in the retina. Thus, modulators of the purinome in the eye might be a source of new therapies for ocular diseases.
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Affiliation(s)
- Kenneth A. Jacobson
- Molecular Recognition Section, Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland
| | - Mortimer M. Civan
- Departments of Physiology and Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania
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44
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Balandya E, Reynolds T, Obaro S, Makani J. Alteration of lymphocyte phenotype and function in sickle cell anemia: Implications for vaccine responses. Am J Hematol 2016; 91:938-46. [PMID: 27237467 DOI: 10.1002/ajh.24438] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Revised: 05/24/2016] [Accepted: 05/26/2016] [Indexed: 02/07/2023]
Abstract
Individuals with sickle cell anemia (SCA) have increased susceptibility to infections, secondary to impairment of immune function. Besides the described dysfunction in innate immunity, including impaired opsonization and phagocytosis of bacteria, evidence of dysfunction of T and B lymphocytes in SCA has also been reported. This includes reduction in the proportion of circulating CD4+ and CD8+ T cells, reduction of CD4+ helper: CD8+ suppressor T cell ratio, aberrant activation and dysfunction of regulatory T cells (Treg ), skewing of CD4+ T cells towards Th2 response and loss of IgM-secreting CD27 + IgM(high) IgD(low) memory B cells. These changes occur on the background of immune activation characterized by predominance of memory CD4+ T cell phenotypes, increased Th17 signaling and elevated levels of C-reactive protein and pro-inflammatory cytokines IL-6 and TNF-α, which may affect the immunogenicity and protective efficacy of vaccines available to prevent infections in SCA. Thus, in order to optimize the use of vaccines in SCA, a thorough understanding of T and B lymphocyte functions and vaccine reactivity among individuals with SCA is needed. Studies should be encouraged of different SCA populations, including sub-Saharan Africa where the burden of SCA is highest. This article summarizes our current understanding of lymphocyte biology in SCA, and highlights areas that warrant future research. Am. J. Hematol. 91:938-946, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Emmanuel Balandya
- Muhimbili University of Health and Allied Sciences (MUHAS); P.O. Box 65001 Dar-es-Salaam Tanzania
| | - Teri Reynolds
- Muhimbili University of Health and Allied Sciences (MUHAS); P.O. Box 65001 Dar-es-Salaam Tanzania
- University of San Francisco, California (UCSF); 505 Parnassus Ave. San Francisco CA 94143 United States
| | - Stephen Obaro
- University of Nebraska Medical Center (UNMC), 982162 Nebraska Medical Center; Omaha Nebraska 68198-2162 United States
- University of Abuja Teaching Hospital; Gwagwalada, P.M.B 228 Abuja Nigeria
| | - Julie Makani
- Muhimbili University of Health and Allied Sciences (MUHAS); P.O. Box 65001 Dar-es-Salaam Tanzania
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45
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Khan SA, Damanhouri G, Ali A, Khan SA, Khan A, Bakillah A, Marouf S, Al Harbi G, Halawani SH, Makki A. Precipitating factors and targeted therapies in combating the perils of sickle cell disease--- A special nutritional consideration. Nutr Metab (Lond) 2016; 13:50. [PMID: 27508000 PMCID: PMC4977632 DOI: 10.1186/s12986-016-0109-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Accepted: 07/22/2016] [Indexed: 01/19/2023] Open
Abstract
Nutritional research in sickle cell disease has been the focus in recent times owing to not only specific nutritional deficiencies, but also the improvements associated with less painful episodes. Though hydroxyurea remains the drug of choice, certain adverse health effects on long term supplementation makes room for researches of different compounds. Macro and micro nutrient deficiencies, along with vitamins, play an important role in not only meeting the calorific needs, but also reducing clinical complications and growth abnormalities. Symptoms of hyper protein metabolism, increased cell turnover, increased cardiac output, and appetite suppression due to enhanced cytokine production, might give us leads for better understanding of the mechanisms involved. Different nutritional approaches comprising of traditional herbal therapies, antioxidants, flavonoids, vitamins, minerals etc., reducing oxidative stress and blood aggregation, have been tried out to increase the health potential. Nutritional therapies may also serve complementary to the newer therapies using ozone, hematopoietic stem cell transplantation, antifungal medications, erythropoietin etc. Herein we try to present a holistic picture of the different patho-physiological mechanisms, and nutritional strategies adopted.
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Affiliation(s)
- Shahida A Khan
- King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah, 21589 Kingdom of Saudi Arabia
| | - Ghazi Damanhouri
- King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah, 21589 Kingdom of Saudi Arabia
| | - Ashraf Ali
- King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah, 21589 Kingdom of Saudi Arabia
| | - Sarah A Khan
- National Brain Research Center, Manesar, Gurgaon, 122051 India
| | - Aziz Khan
- King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah, 21589 Kingdom of Saudi Arabia
| | - Ahmed Bakillah
- Department of Medicine, SUNY Downstate Medical Center, 450 Clarkson Ave., Brooklyn, New York 11203 United State of America (USA)
| | - Samy Marouf
- Department of Hematology, King Fahd Hospital of the Armed forces, Jeddah, Kingdom of Saudi Arabia ; Department of Medical Laboratory, King Fahd Hospital of the Armed forces, Jeddah, Kingdom of Saudi Arabia
| | - Ghazi Al Harbi
- Department of Hematology, Soliman Fakeeh Hospital Jeddah, Jeddah, Kingdom of Saudi Arabia
| | - Saeed H Halawani
- Department of Hematology, Umm Al Qura University, Faculty of Medicine, Makkah, Kingdom of Saudi Arabia
| | - Ahmad Makki
- King Fahd Medical Research Center, King Abdulaziz University, P.O. Box 80216, Jeddah, 21589 Kingdom of Saudi Arabia
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Abstract
Cellular stress or apoptosis triggers the release of ATP, ADP and other nucleotides into the extracellular space. Extracellular nucleotides function as autocrine and paracrine signalling molecules by activating cell-surface P2 purinergic receptors that elicit pro-inflammatory immune responses. Over time, extracellular nucleotides are metabolized to adenosine, leading to reduced P2 signalling and increased signalling through anti-inflammatory adenosine (P1 purinergic) receptors. Here, we review how local purinergic signalling changes over time during tissue responses to injury or disease, and we discuss the potential of targeting purinergic signalling pathways for the immunotherapeutic treatment of ischaemia, organ transplantation, autoimmunity or cancer.
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Affiliation(s)
- Caglar Cekic
- Department of Molecular Biology and Genetics, Bilkent University, Ankara 06800, Turkey
| | - Joel Linden
- Division of Developmental Immunology, La Jolla Institute for Allergy and Immunology, La Jolla, California 92037, USA
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47
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Abraham A, Jacobsohn DA, Bollard CM. Cellular therapy for sickle cell disease. Cytotherapy 2016; 18:1360-1369. [PMID: 27421743 DOI: 10.1016/j.jcyt.2016.06.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 05/25/2016] [Accepted: 06/16/2016] [Indexed: 02/02/2023]
Abstract
Sickle cell disease (SCD) is a monogenic red cell disorder affecting more than 300 000 annual births worldwide and leading to significant organ toxicity and premature mortality. Although chronic therapies such as hydroxyurea have improved outcomes, more durable therapeutic and curative options are still being investigated. Newer understanding of the disease has implicated invariant natural killer T cells as a critical immune profile that potentiates SCD. Hence, targeting this cell population may offer a new approach to disease management. Hematopoietic stem cell transplant is a curative option for patients with SCD, but the under-representation of minorities on the unrelated donor registry means that this is not a feasible option for more than 75% of patients. Work in this area has therefore focused on increasing the donor pool and decreasing transplant-related toxicities to make this a treatment option for the majority of patients with SCD. This review focuses on the currently available cell and gene therapies for patients with SCD and acknowledges that newer gene-editing approaches to improve gene therapy efficiency and safety are the next wave of potentially curative approaches.
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Affiliation(s)
- Allistair Abraham
- Division of Blood and Marrow Transplant, Children's National Health System and The George Washington University, Washington, DC, USA; Program for Cell Enhancement and Technologies for Immunotherapy, Children's National Health System and The George Washington University, Washington, DC, USA.
| | - David A Jacobsohn
- Division of Blood and Marrow Transplant, Children's National Health System and The George Washington University, Washington, DC, USA
| | - Catherine M Bollard
- Division of Blood and Marrow Transplant, Children's National Health System and The George Washington University, Washington, DC, USA; Program for Cell Enhancement and Technologies for Immunotherapy, Children's National Health System and The George Washington University, Washington, DC, USA
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48
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Sickle cell disease biochip: a functional red blood cell adhesion assay for monitoring sickle cell disease. Transl Res 2016; 173:74-91.e8. [PMID: 27063958 PMCID: PMC4959913 DOI: 10.1016/j.trsl.2016.03.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 03/08/2016] [Accepted: 03/12/2016] [Indexed: 01/10/2023]
Abstract
Sickle cell disease (SCD) afflicts millions of people worldwide and is associated with considerable morbidity and mortality. Chronic and acute vaso-occlusion are the clinical hallmarks of SCD and can result in pain crisis, widespread organ damage, and early movtality. Even though the molecular underpinnings of SCD were identified more than 60 years ago, there are no molecular or biophysical markers of disease severity that are feasibly measured in the clinic. Abnormal cellular adhesion to vascular endothelium is at the root of vaso-occlusion. However, cellular adhesion is not currently evaluated clinically. Here, we present a clinically applicable microfluidic device (SCD biochip) that allows serial quantitative evaluation of red blood cell (RBC) adhesion to endothelium-associated protein-immobilized microchannels, in a closed and preprocessing-free system. With the SCD biochip, we have analyzed blood samples from more than 100 subjects and have shown associations between the measured RBC adhesion to endothelium-associated proteins (fibronectin and laminin) and individual RBC characteristics, including hemoglobin content, fetal hemoglobin concentration, plasma lactate dehydrogenase level, and reticulocyte count. The SCD biochip is a functional adhesion assay, reflecting quantitative evaluation of RBC adhesion, which could be used at baseline, during crises, relative to various long-term complications, and before and after therapeutic interventions.
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49
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Beyond hydroxyurea: new and old drugs in the pipeline for sickle cell disease. Blood 2016; 127:810-9. [PMID: 26758919 DOI: 10.1182/blood-2015-09-618553] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2015] [Accepted: 10/21/2015] [Indexed: 01/09/2023] Open
Abstract
Despite Food and Drug Administration (FDA) approval of hydroxyurea to reduce the frequency of vaso-occlusive episodes, sickle cell disease (SCD) has continued to be treated primarily with analgesics for pain relief. However, elucidation of the multiple pathophysiologic mechanisms leading to vaso-occlusion and tissue injury in SCD has now resulted in a burgeoning effort to identify new treatment modalities to prevent or ameliorate the consequences of the disease. Development of new drugs as well as investigation of drugs previously used in other settings have targeted cell adhesion, inflammatory pathways, upregulation of hemoglobin F, hemoglobin polymerization and sickling, coagulation, and platelet activation. Although these efforts have not yet yielded drugs ready for FDA approval, several early studies have been extremely encouraging. Moreover, the marked increase in clinical pharmaceutical research addressing SCD and the new and old drugs in the pipeline make it reasonable to expect that we will soon have new treatments for SCD.
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50
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Neutrophils, platelets, and inflammatory pathways at the nexus of sickle cell disease pathophysiology. Blood 2016; 127:801-9. [PMID: 26758915 DOI: 10.1182/blood-2015-09-618538] [Citation(s) in RCA: 269] [Impact Index Per Article: 33.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 10/28/2015] [Indexed: 02/07/2023] Open
Abstract
Sickle cell disease (SCD) is a severe genetic blood disorder characterized by hemolytic anemia, episodic vaso-occlusion, and progressive organ damage. Current management of the disease remains symptomatic or preventative. Specific treatment targeting major complications such as vaso-occlusion is still lacking. Recent studies have identified various cellular and molecular factors that contribute to the pathophysiology of SCD. Here, we review the role of these elements and discuss the opportunities for therapeutic intervention.
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