1
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Muppidi P, Wright E, Wassmer SC, Gupta H. Diagnosis of cerebral malaria: Tools to reduce Plasmodium falciparum associated mortality. Front Cell Infect Microbiol 2023; 13:1090013. [PMID: 36844403 PMCID: PMC9947298 DOI: 10.3389/fcimb.2023.1090013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Accepted: 01/24/2023] [Indexed: 02/11/2023] Open
Abstract
Cerebral malaria (CM) is a major cause of mortality in Plasmodium falciparum (Pf) infection and is associated with the sequestration of parasitised erythrocytes in the microvasculature of the host's vital organs. Prompt diagnosis and treatment are key to a positive outcome in CM. However, current diagnostic tools remain inadequate to assess the degree of brain dysfunction associated with CM before the window for effective treatment closes. Several host and parasite factor-based biomarkers have been suggested as rapid diagnostic tools with potential for early CM diagnosis, however, no specific biomarker signature has been validated. Here, we provide an updated review on promising CM biomarker candidates and evaluate their applicability as point-of-care tools in malaria-endemic areas.
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Affiliation(s)
- Pranavi Muppidi
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Emily Wright
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Samuel C. Wassmer
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Himanshu Gupta
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Department of Biotechnology, Institute of Applied Sciences & Humanities, GLA University, Mathura, UP, India
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2
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Martinez de Lizarrondo S, Jacqmarcq C, Naveau M, Navarro-Oviedo M, Pedron S, Adam A, Freis B, Allouche S, Goux D, Razafindrakoto S, Gazeau F, Mertz D, Vivien D, Bonnard T, Gauberti M. Tracking the immune response by MRI using biodegradable and ultrasensitive microprobes. SCIENCE ADVANCES 2022; 8:eabm3596. [PMID: 35857494 PMCID: PMC9278862 DOI: 10.1126/sciadv.abm3596] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Accepted: 05/26/2022] [Indexed: 06/03/2023]
Abstract
Molecular magnetic resonance imaging (MRI) holds great promise for diagnosis and therapeutic monitoring in a wide range of diseases. However, the low intrinsic sensitivity of MRI to detect exogenous contrast agents and the lack of biodegradable microprobes have prevented its clinical development. Here, we synthetized a contrast agent for molecular MRI based on a previously unknown mechanism of self-assembly of catechol-coated magnetite nanocrystals into microsized matrix-based particles. The resulting biodegradable microprobes (M3P for microsized matrix-based magnetic particles) carry up to 40,000 times higher amounts of superparamagnetic material than classically used nanoparticles while preserving favorable biocompatibility and excellent water dispersibility. After conjugation to monoclonal antibodies, targeted M3P display high sensitivity and specificity to detect inflammation in vivo in the brain, kidneys, and intestinal mucosa. The high payload of superparamagnetic material, excellent toxicity profile, short circulation half-life, and widespread reactivity of the M3P particles provides a promising platform for clinical translation of immuno-MRI.
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Affiliation(s)
- Sara Martinez de Lizarrondo
- Normandie Université, UNICAEN, INSERM, PhIND (Physiopathology and Imaging of Neurological Disorders), Institut Blood and Brain @ Caen-Normandie, Cyceron, 14000 Caen, France
| | - Charlene Jacqmarcq
- Normandie Université, UNICAEN, INSERM, PhIND (Physiopathology and Imaging of Neurological Disorders), Institut Blood and Brain @ Caen-Normandie, Cyceron, 14000 Caen, France
| | - Mikael Naveau
- Normandie Université, UMS 3408 Cyceron, CNRS, University of Caen Normandy, GIP CYCERON, Caen, France
| | - Manuel Navarro-Oviedo
- Normandie Université, UNICAEN, INSERM, PhIND (Physiopathology and Imaging of Neurological Disorders), Institut Blood and Brain @ Caen-Normandie, Cyceron, 14000 Caen, France
| | - Swannie Pedron
- Normandie Université, UNICAEN, INSERM, PhIND (Physiopathology and Imaging of Neurological Disorders), Institut Blood and Brain @ Caen-Normandie, Cyceron, 14000 Caen, France
| | - Alexandre Adam
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), UMR-7504 CNRS—Université de Strasbourg, 23 rue du Lœss, 67034 Strasbourg, France
| | - Barbara Freis
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), UMR-7504 CNRS—Université de Strasbourg, 23 rue du Lœss, 67034 Strasbourg, France
| | - Stephane Allouche
- CHU Caen, Department of Biochemistry, CHU de Caen Côte de Nacre, Caen, France
| | - Didier Goux
- Centre de Microscopie Appliquée à la Biologie (CMAbio), UniCaen, Normandie University, SF4206 Icore, 14000 Caen, France
| | - Sarah Razafindrakoto
- MSC, Université de Paris CNRS, UMR7057, 45 rue des Saints Pères 75006, Paris, France
| | - Florence Gazeau
- MSC, Université de Paris CNRS, UMR7057, 45 rue des Saints Pères 75006, Paris, France
| | - Damien Mertz
- Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS), UMR-7504 CNRS—Université de Strasbourg, 23 rue du Lœss, 67034 Strasbourg, France
| | - Denis Vivien
- Normandie Université, UNICAEN, INSERM, PhIND (Physiopathology and Imaging of Neurological Disorders), Institut Blood and Brain @ Caen-Normandie, Cyceron, 14000 Caen, France
- CHU Caen, Clinical Research Department, CHU de Caen Côte de Nacre, Caen, France
| | - Thomas Bonnard
- Normandie Université, UNICAEN, INSERM, PhIND (Physiopathology and Imaging of Neurological Disorders), Institut Blood and Brain @ Caen-Normandie, Cyceron, 14000 Caen, France
| | - Maxime Gauberti
- Normandie Université, UNICAEN, INSERM, PhIND (Physiopathology and Imaging of Neurological Disorders), Institut Blood and Brain @ Caen-Normandie, Cyceron, 14000 Caen, France
- CHU Caen, Department of Diagnostic Imaging and Interventional Radiology, CHU de Caen Côte de Nacre, Caen, France
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3
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Rawish E, Nording H, Münte T, Langer HF. Platelets as Mediators of Neuroinflammation and Thrombosis. Front Immunol 2020; 11:548631. [PMID: 33123127 PMCID: PMC7572851 DOI: 10.3389/fimmu.2020.548631] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 09/14/2020] [Indexed: 12/20/2022] Open
Abstract
Beyond platelets function in hemostasis, there is emerging evidence to suggest that platelets contribute crucially to inflammation and immune responses. Therefore, considering the detrimental role of inflammatory conditions in severe neurological disorders such as multiple sclerosis or stroke, this review outlines platelets involvement in neuroinflammation. For this, distinct mechanisms of platelet-mediated thrombosis and inflammation are portrayed, focusing on the interaction of platelet receptors with other immune cells as well as brain endothelial cells. Furthermore, we draw attention to the intimate interplay between platelets and the complement system as well as between platelets and plasmatic coagulation factors in the course of neuroinflammation. Following the thorough exposition of preclinical approaches which aim at ameliorating disease severity after inducing experimental autoimmune encephalomyelitis (a counterpart of multiple sclerosis in mice) or brain ischemia-reperfusion injury, the clinical relevance of platelet-mediated neuroinflammation is addressed. Thus, current as well as future propitious translational and clinical strategies for the treatment of neuro-inflammatory diseases by affecting platelet function are illustrated, emphasizing that targeting platelet-mediated neuroinflammation could become an efficient adjunct therapy to mitigate disease severity of multiple sclerosis or stroke associated brain injury.
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Affiliation(s)
- Elias Rawish
- University Hospital Schleswig-Holstein, Medical Clinic II, University Heart Center Lübeck, Lübeck, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - Henry Nording
- University Hospital Schleswig-Holstein, Medical Clinic II, University Heart Center Lübeck, Lübeck, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Lübeck, Germany
| | - Thomas Münte
- University Hospital Schleswig-Holstein, Clinic for Neurology, Lübeck, Germany
| | - Harald F Langer
- University Hospital Schleswig-Holstein, Medical Clinic II, University Heart Center Lübeck, Lübeck, Germany.,DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Lübeck, Germany
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4
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Bagi Z, Couch Y, Broskova Z, Perez-Balderas F, Yeo T, Davis S, Fischer R, Sibson NR, Davis BG, Anthony DC. Extracellular vesicle integrins act as a nexus for platelet adhesion in cerebral microvessels. Sci Rep 2019; 9:15847. [PMID: 31676801 PMCID: PMC6825169 DOI: 10.1038/s41598-019-52127-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/14/2019] [Indexed: 01/13/2023] Open
Abstract
Circulating extracellular vesicles (EVs) regulate signaling pathways via receptor-ligand interactions and content delivery, after attachment or internalization by endothelial cells. However, they originate from diverse cell populations and are heterogeneous in composition. To determine the effects of specific surface molecules, the use of synthetic EV mimetics permits the study of specific EV receptor-ligand interactions. Here, we used endogenous EVs derived from the circulation of rats, as well as ligand-decorated synthetic microparticles (MPs) to examine the role of integrin αvβ3 in platelet adhesion under flow in structurally intact cerebral arteries. At an intraluminal pressure of 50 mmHg and flow rate of 10 µl/min, platelets were delivered to the artery lumen and imaged with whole-field fluorescent microscopy. Under basal conditions very few platelets bound to the endothelium. However, adhesion events were markedly increased following the introduction of arginine-glycine-aspartate (RGD)-labelled synthetic MPs or endogenously-derived EVs from experimental stroke animals carrying excess RGD proteins, including vitronectin, CD40-ligand and thrombospondin-1. These data, which were generated in a dynamic and physiologically relevant system, demonstrate the importance of vesicle-carried RGD ligands in platelet adherence to the cerebrovascular endothelium and highlight the ability of synthetic EVs to isolate and identify key components of the molecular handshake between EVs and their targets.
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Affiliation(s)
- Zsolt Bagi
- Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, United Kingdom.
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA.
| | - Yvonne Couch
- RDM-Investigative Medicine, University of Oxford, Oxford, OX3 7LJ, United Kingdom
| | - Zuzana Broskova
- Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, United Kingdom
- Department of Physiology, Medical College of Georgia, Augusta University, Augusta, GA, 30912, USA
| | - Francisco Perez-Balderas
- Chemistry Research Laboratory, University of Oxford, Oxford, OX1 3TA, United Kingdom
- Gray Institute for Radiation Oncology and Biology, University of Oxford, Oxford, OX3 7DQ, United Kingdom
| | - Tianrong Yeo
- Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, United Kingdom
| | - Simon Davis
- TDI Mass Spectrometry Laboratory, Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7FZ, UK
| | - Roman Fischer
- TDI Mass Spectrometry Laboratory, Target Discovery Institute, Nuffield Department of Medicine, University of Oxford, Roosevelt Drive, Oxford, OX3 7FZ, UK
| | - Nicola R Sibson
- Gray Institute for Radiation Oncology and Biology, University of Oxford, Oxford, OX3 7DQ, United Kingdom
| | - Benjamin G Davis
- Chemistry Research Laboratory, University of Oxford, Oxford, OX1 3TA, United Kingdom
| | - Daniel C Anthony
- Department of Pharmacology, University of Oxford, Oxford, OX1 3QT, United Kingdom.
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5
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Guo L, Rondina MT. The Era of Thromboinflammation: Platelets Are Dynamic Sensors and Effector Cells During Infectious Diseases. Front Immunol 2019; 10:2204. [PMID: 31572400 PMCID: PMC6753373 DOI: 10.3389/fimmu.2019.02204] [Citation(s) in RCA: 132] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 08/30/2019] [Indexed: 12/12/2022] Open
Abstract
Platelets are anucleate cells produced by megakaryocytes. In recent years, a robust body of literature supports the evolving role of platelets as key sentinel and effector cells in infectious diseases, especially critical in bridging hemostatic, inflammatory, and immune continuums. Upon intravascular pathogen invasion, platelets can directly sense viral, parasitic, and bacterial infections through pattern recognition receptors and integrin receptors or pathogen: immunoglobulin complexes through Fc and complement receptors—although our understanding of these interactions remains incomplete. Constantly scanning for areas of injury or inflammation as they circulate in the vasculature, platelets also indirectly respond to pathogen invasion through interactions with leukocytes and the endothelium. Following antigen recognition, platelets often become activated. Through a diverse repertoire of mechanisms, activated platelets can directly sequester or kill pathogens, or facilitate pathogen clearance by activating macrophages and neutrophils, promoting neutrophil extracellular traps (NETs) formation, forming platelet aggregates and microthrombi. At times, however, platelet activation may also be injurious to the host, exacerbating inflammation and promoting endothelial damage and thrombosis. There are many gaps in our understandings of the role of platelets in infectious diseases. However, with the emergence of advanced technologies, our knowledge is increasing. In the current review, we mainly discuss these evolving roles of platelets under four different infectious pathogen infections, of which are dengue, malaria, Esterichia coli (E. coli) and staphylococcus aureus S. aureus, highlighting the complex interplay of these processes with hemostatic and thrombotic pathways.
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Affiliation(s)
- Li Guo
- University of Utah Molecular Medicine Program, Salt Lake City, UT, United States
| | - Matthew T Rondina
- University of Utah Molecular Medicine Program, Salt Lake City, UT, United States.,Department of Internal Medicine, University of Utah, Salt Lake City, UT, United States.,Department of Pathology, University of Utah, Salt Lake City, UT, United States.,George E. Wahlen VAMC Department of Internal Medicine and GRECC, Salt Lake City, UT, United States
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6
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MRI demonstrates glutamine antagonist-mediated reversal of cerebral malaria pathology in mice. Proc Natl Acad Sci U S A 2018; 115:E12024-E12033. [PMID: 30514812 DOI: 10.1073/pnas.1812909115] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The deadliest complication of Plasmodium falciparum infection is cerebral malaria (CM), with a case fatality rate of 15 to 25% in African children despite effective antimalarial chemotherapy. No adjunctive treatments are yet available for this devastating disease. We previously reported that the glutamine antagonist 6-diazo-5-oxo-l-norleucine (DON) rescued mice from experimental CM (ECM) when administered late in the infection, a time by which mice had already suffered blood-brain barrier (BBB) dysfunction, brain swelling, and hemorrhaging. Herein, we used longitudinal MR imaging to visualize brain pathology in ECM and the impact of a new DON prodrug, JHU-083, on disease progression in mice. We demonstrate in vivo the reversal of disease markers in symptomatic, infected mice following treatment, including the resolution of edema and BBB disruption, findings usually associated with a fatal outcome in children and adults with CM. Our results support the premise that JHU-083 is a potential adjunctive treatment that could rescue children and adults from fatal CM.
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7
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Gauberti M, Fournier AP, Docagne F, Vivien D, Martinez de Lizarrondo S. Molecular Magnetic Resonance Imaging of Endothelial Activation in the Central Nervous System. Theranostics 2018; 8:1195-1212. [PMID: 29507614 PMCID: PMC5835930 DOI: 10.7150/thno.22662] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Accepted: 01/12/2018] [Indexed: 01/01/2023] Open
Abstract
Endothelial cells of the central nervous system over-express surface proteins during neurological disorders, either as a cause, or a consequence, of the disease. Since the cerebral vasculature is easily accessible by large contrast-carrying particles, it constitutes a target of choice for molecular magnetic resonance imaging (MRI). In this review, we highlight the most recent advances in molecular MRI of brain endothelial activation and focus on the development of micro-sized particles of iron oxide (MPIO) targeting adhesion molecules including intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), P-Selectin and E-Selectin. We also discuss the perspectives and challenges for the clinical application of this technology in neurovascular disorders (ischemic stroke, intracranial hemorrhage, subarachnoid hemorrhage, diabetes mellitus), neuroinflammatory disorders (multiple sclerosis, brain infectious diseases, sepsis), neurodegenerative disorders (Alzheimer's disease, vascular dementia, aging) and brain cancers (primitive neoplasms, metastasis).
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Affiliation(s)
- Maxime Gauberti
- Normandie Univ, UNICAEN, INSERM, INSERM UMR-S U1237, Physiopathology and Imaging for Neurological Disorders (PhIND), Cyceron, 14000 Caen, France
- CHU Caen, Department of diagnostic imaging and interventional radiology, CHU de Caen Côte de Nacre, Caen, France
| | - Antoine P. Fournier
- Normandie Univ, UNICAEN, INSERM, INSERM UMR-S U1237, Physiopathology and Imaging for Neurological Disorders (PhIND), Cyceron, 14000 Caen, France
| | - Fabian Docagne
- Normandie Univ, UNICAEN, INSERM, INSERM UMR-S U1237, Physiopathology and Imaging for Neurological Disorders (PhIND), Cyceron, 14000 Caen, France
| | - Denis Vivien
- Normandie Univ, UNICAEN, INSERM, INSERM UMR-S U1237, Physiopathology and Imaging for Neurological Disorders (PhIND), Cyceron, 14000 Caen, France
- CHU Caen, Clinical Research Department, CHU de Caen Côte de Nacre, Caen, France
| | - Sara Martinez de Lizarrondo
- Normandie Univ, UNICAEN, INSERM, INSERM UMR-S U1237, Physiopathology and Imaging for Neurological Disorders (PhIND), Cyceron, 14000 Caen, France
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Lim B, Yao Y, Huang ALI, Yap ML, Flierl U, Palasubramaniam J, Zaldivia MT, Wang X, Peter K. A Unique Recombinant Fluoroprobe Targeting Activated Platelets Allows In Vivo Detection of Arterial Thrombosis and Pulmonary Embolism Using a Novel Three-Dimensional Fluorescence Emission Computed Tomography (FLECT) Technology. Am J Cancer Res 2017; 7:1047-1061. [PMID: 28435447 PMCID: PMC5399575 DOI: 10.7150/thno.18099] [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: 10/26/2016] [Accepted: 01/17/2017] [Indexed: 01/21/2023] Open
Abstract
Progress in pharmaceutical development is highly-dependent on preclinical in vivo animal studies. Small animal imaging is invaluable for the identification of new disease markers and the evaluation of drug efficacy. Here, we report for the first time the use of a three-dimensional fluorescence bioimager called FLuorescence Emission Computed Tomography (FLECT) for the detection of a novel recombinant fluoroprobe that is safe, easily prepared on a large scale and stably stored prior to scan. This novel fluoroprobe (Targ-Cy7) comprises a single-chain antibody-fragment (scFvTarg), which binds exclusively to activated-platelets, conjugated to a near-infrared (NIR) dye, Cy7, for detection. Upon mouse carotid artery injury, the injected fluoroprobe circulates and binds within the platelet-rich thrombus. This specific in vivo binding of the fluoroprobe to the thrombus, compared to its non-targeting control-fluoroprobe, is detected by the FLECT imager. The analyzed FLECT image quantifies the NIR signal and localizes it to the site of vascular injury. The detected fluorescence is further verified using a two-dimensional IVIS® Lumina scanner, where significant NIR fluorescence is detected in vivo at the thrombotic site, and ex vivo, at the injured carotid artery. Furthermore, fluorescence levels in various organs have also been quantified for biodistribution, with the highest fluoroprobe uptake shown to be in the injured artery. Subsequently, this live animal imaging technique is successfully employed to monitor the response of the induced thrombus to treatment over time. This demonstrates the potential of using longitudinal FLECT scanning to examine the efficacy of candidate drugs in preclinical settings. Besides intravascular thrombosis, we have shown that this non-invasive FLECT-imaging can also detect in vivo pulmonary embolism. Overall, this report describes a novel fluorescence-based preclinical imaging modality that uses an easy-to-prepare and non-radioactive recombinant fluoroprobe. This represents a unique tool to study mechanisms of thromboembolic diseases and it will strongly facilitate the in vivo testing of antithrombotic drugs. Furthermore, the non-radiation nature, low-cost, high sensitivity, and the rapid advancement of optical scanning technologies make this fluorescence imaging an attractive development for future clinical applications.
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9
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Perez-Balderas F, van Kasteren SI, Aljabali AAA, Wals K, Serres S, Jefferson A, Sarmiento Soto M, Khrapitchev AA, Larkin JR, Bristow C, Lee SS, Bort G, De Simone F, Campbell SJ, Choudhury RP, Anthony DC, Sibson NR, Davis BG. Covalent assembly of nanoparticles as a peptidase-degradable platform for molecular MRI. Nat Commun 2017; 8:14254. [PMID: 28198362 PMCID: PMC5316865 DOI: 10.1038/ncomms14254] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 12/08/2016] [Indexed: 12/02/2022] Open
Abstract
Ligand-conjugated microparticles of iron oxide (MPIO) have the potential to provide high sensitivity contrast for molecular magnetic resonance imaging (MRI). However, the accumulation and persistence of non-biodegradable micron-sized particles in liver and spleen precludes their clinical use and limits the translational potential of MPIO-based contrast agents. Here we show that ligand-targeted MPIO derived from multiple iron oxide nanoparticles may be coupled covalently through peptide linkers that are designed to be cleaved by intracellular macrophage proteases. The synthesized particles possess potential characteristics for targeted MRI contrast agents, including high relaxivity, unappreciable sedimentation, clearance from circulation and no overt toxicity. Importantly, we demonstrate that these particles are rapidly degraded both in vitro and in vivo, and that the targeted probes can be used for detection of inflammation in vivo using MRI. This approach provides a platform for molecular MRI contrast agents that is potentially more suitable for translation to humans.
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Affiliation(s)
- Francisco Perez-Balderas
- Department of Oncology, Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Sander I. van Kasteren
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Alaa A. A. Aljabali
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
- Department of Cardiovascular Medicine and Oxford Acute Vascular Imaging Centre, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Kim Wals
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
| | - Sébastien Serres
- Department of Oncology, Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Andrew Jefferson
- Department of Cardiovascular Medicine and Oxford Acute Vascular Imaging Centre, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Manuel Sarmiento Soto
- Department of Oncology, Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Alexandre A. Khrapitchev
- Department of Oncology, Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - James R Larkin
- Department of Oncology, Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Claire Bristow
- Department of Oncology, Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Seung Seo Lee
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Guillaume Bort
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Filippo De Simone
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
| | - Sandra J. Campbell
- Department of Oncology, Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Robin P. Choudhury
- Department of Cardiovascular Medicine and Oxford Acute Vascular Imaging Centre, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Daniel C. Anthony
- Department of Pharmacology, University of Oxford, Oxford OX1 3QT, UK
| | - Nicola R. Sibson
- Department of Oncology, Cancer Research UK & Medical Research Council Oxford Institute for Radiation Oncology, University of Oxford, Oxford OX3 7DQ, UK
| | - Benjamin G. Davis
- Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Oxford OX1 3TA, UK
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10
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Liu J, Xu J, Zhou J, Zhang Y, Guo D, Wang Z. Fe 3O 4-based PLGA nanoparticles as MR contrast agents for the detection of thrombosis. Int J Nanomedicine 2017; 12:1113-1126. [PMID: 28223802 PMCID: PMC5310639 DOI: 10.2147/ijn.s123228] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Thrombotic disease is a great threat to human health, and early detection is particularly important. Magnetic resonance (MR) molecular imaging provides noninvasive imaging with the potential for early disease diagnosis. In this study, we developed Fe3O4-based poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) surface-modified with a cyclic Arg-Gly-Asp (cRGD) peptide as an MR contrast agent for the detection of thrombosis. The physical and chemical characteristics, biological toxicity, ability to target thrombi, and biodistribution of the NPs were studied. The Fe3O4-PLGA-cRGD NPs were constructed successfully, and hematologic and pathologic assays indicated no in vivo toxicity of the NPs. In a rat model of FeCl3-induced abdominal aorta thrombosis, the NPs readily and selectively accumulated on the surface of the thrombosis and under vascular endothelial cells ex vivo and in vivo. In the in vivo experiment, the biodistribution of the NPs suggested that the NPs might be internalized by the macrophages of the reticuloendothelial system in the liver and the spleen. The T2 signal decreased at the mural thrombus 10 min after injection and then gradually increased until 50 min. These results suggest that the NPs are suitable for in vivo molecular imaging of thrombosis under high shear stress conditions and represent a very promising MR contrast agent for sensitive and specific detection of thrombosis.
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Affiliation(s)
| | | | | | | | | | - Zhigang Wang
- Department of Ultrasound, Institute of Ultrasound Imaging, The Second Affiliated Hospital of Chongqing Medical University, Yuzhong, Chongqing, People's Republic of China
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11
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Molecular Imaging of Activated Platelets Allows the Detection of Pulmonary Embolism with Magnetic Resonance Imaging. Sci Rep 2016; 6:25044. [PMID: 27138487 PMCID: PMC4853725 DOI: 10.1038/srep25044] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 04/08/2016] [Indexed: 01/04/2023] Open
Abstract
Early and reliable detection of pulmonary embolism (PE) is critical for improving patient morbidity and mortality. The desire for low-threshold screening for pulmonary embolism is contradicted by unfavorable radiation of currently used computed tomography or nuclear techniques, while standard magnetic resonance imaging still struggles to provide sufficient diagnostic sensitivity in the lung. In this study we evaluate a molecular-targeted contrast agent against activated platelets for non-invasive detection of murine pulmonary thromboembolism using magnetic resonance imaging. By intravenous injection of human thrombin, pulmonary thromboembolism were consistently induced as confirmed by immunohistochemistry of the lung. Magnetic resonance imaging after thrombin injection showed local tissue edema in weighted images which co-localized with the histological presence of pulmonary thromboembolism. Furthermore, injection of a functionalized contrast agent targeting activated platelets provided sensitive evidence of focal accumulation of activated platelets within the edematous area, which, ex vivo, correlated well with the size of the pulmonary embolism. In summary, we here show delivery and specific binding of a functionalized molecular contrast agent against activated platelets for targeting pulmonary thromboembolism. Going forward, molecular imaging may provide new opportunities to increase sensitivity of magnetic resonance imaging for detection of pulmonary embolism.
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Wang X, Gkanatsas Y, Palasubramaniam J, Hohmann JD, Chen YC, Lim B, Hagemeyer CE, Peter K. Thrombus-Targeted Theranostic Microbubbles: A New Technology towards Concurrent Rapid Ultrasound Diagnosis and Bleeding-free Fibrinolytic Treatment of Thrombosis. Am J Cancer Res 2016; 6:726-38. [PMID: 27022419 PMCID: PMC4805666 DOI: 10.7150/thno.14514] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 02/08/2016] [Indexed: 12/29/2022] Open
Abstract
Rationale: Myocardial infarction and stroke are leading causes of morbidity/mortality. The typical underlying pathology is the formation of thrombi/emboli and subsequent vessel occlusion. Systemically administered fibrinolytic drugs are the most effective pharmacological therapy. However, bleeding complications are relatively common and this risk as such limits their broader use. Furthermore, a rapid non-invasive imaging technology is not available. Thereby, many thrombotic events are missed or only diagnosed when ischemic damage has already occurred. Objective: Design and preclinical testing of a novel 'theranostic' technology for the rapid non-invasive diagnosis and effective, bleeding-free treatment of thrombosis. Methods and Results: A newly created, innovative theranostic microbubble combines a recombinant fibrinolytic drug, an echo-enhancing microbubble and a recombinant thrombus-targeting device in form of an activated-platelet-specific single-chain antibody. After initial in vitro proof of functionality, we tested this theranostic microbubble both in ultrasound imaging and thrombolytic therapy using a mouse model of ferric-chloride-induced thrombosis in the carotid artery. We demonstrate the reliable highly sensitive detection of in vivo thrombi and the ability to monitor their size changes in real time. Furthermore, these theranostic microbubbles proofed to be as effective in thrombolysis as commercial urokinase but without the prolongation of bleeding time as seen with urokinase. Conclusions: We describe a novel theranostic technology enabling simultaneous diagnosis and treatment of thrombosis, as well as monitoring of success or failure of thrombolysis. This technology holds promise for major progress in rapid diagnosis and bleeding-free thrombolysis thereby potentially preventing the often devastating consequences of thrombotic disease in many patients.
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Melemenidis S, Jefferson A, Ruparelia N, Akhtar AM, Xie J, Allen D, Hamilton A, Larkin JR, Perez-Balderas F, Smart SC, Muschel RJ, Chen X, Sibson NR, Choudhury RP. Molecular magnetic resonance imaging of angiogenesis in vivo using polyvalent cyclic RGD-iron oxide microparticle conjugates. Theranostics 2015; 5:515-29. [PMID: 25767618 PMCID: PMC4350013 DOI: 10.7150/thno.10319] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 01/12/2015] [Indexed: 02/06/2023] Open
Abstract
Angiogenesis is an essential component of tumour growth and, consequently, an important target both therapeutically and diagnostically. The cell adhesion molecule α(v)β(3) integrin is a specific marker of angiogenic vessels and the most prevalent vascular integrin that binds the amino acid sequence arginine-glycine-aspartic acid (RGD). Previous studies using RGD-targeted nanoparticles (20-50 nm diameter) of iron oxide (NPIO) for magnetic resonance imaging (MRI) of tumour angiogenesis, have identified a number of limitations, including non-specific extravasation, long blood half-life (reducing specific contrast) and low targeting valency. The aim of this study, therefore, was to determine whether conjugation of a cyclic RGD variant [c(RGDyK)], with enhanced affinity for α(v)β(3), to microparticles of iron oxide (MPIO) would provide a more sensitive contrast agent for imaging of angiogenic tumour vessels. Cyclic RGD [c(RGDyK)] and RAD [c(RADyK)] based peptides were coupled to 2.8 μm MPIO, and binding efficacy tested both in vitro and in vivo. Significantly greater specific binding of c(RGDyK)-MPIO to S-nitroso-n-acetylpenicillamine (SNAP)-stimulated human umbilical vein endothelial cells in vitro than PBS-treated cells was demonstrated under both static (14-fold increase; P < 0.001) and flow (44-fold increase; P < 0.001) conditions. Subsequently, mice bearing subcutaneous colorectal (MC38) or melanoma (B16F10) derived tumours underwent in vivo MRI pre- and post-intravenous administration of c(RGDyK)-MPIO or c(RADyK)-MPIO. A significantly greater volume of MPIO-induced hypointensities were found in c(RGDyK)-MPIO injected compared to c(RADyK)-MPIO injected mice, in both tumour models (P < 0.05). Similarly, administration of c(RGDyK)-MPIO induced a greater reduction in mean tumour T(2)* relaxation times than the control agent in both tumour models (melanoma P < 0.001; colorectal P < 0.0001). Correspondingly, MPIO density per tumour volume assessed immunohistochemically was significantly greater for c(RGDyK)-MPIO than c(RADyK)-MPIO injected animals, in both melanoma (P < 0.05) and colorectal (P < 0.0005) tumours. In both cases, binding of c(RGDyK)-MPIO co-localised with α(v)β(3) expression. Comparison of RGD-targeted and dynamic contrast enhanced (DCE) MRI assessment of tumour perfusion indicated sensitivity to different vascular features. This study demonstrates specific binding of c(RGDyK)-MPIO to α(v)β(3) expressing neo-vessels, with marked and quantifiable contrast and rapid clearance of unbound particles from the blood circulation compared to NPIO. Combination of this molecular MRI approach with conventional DCE MRI will enable integrated molecular, anatomical and perfusion tumour imaging.
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Affiliation(s)
- Stavros Melemenidis
- 2. Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Andrew Jefferson
- 1. Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, United Kingdom
| | - Neil Ruparelia
- 1. Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, United Kingdom
| | - Asim M Akhtar
- 1. Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, United Kingdom
| | - Jin Xie
- 3. Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, Maryland 20892, United States
| | - Danny Allen
- 2. Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Alastair Hamilton
- 2. Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - James R Larkin
- 2. Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Francisco Perez-Balderas
- 2. Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Sean C Smart
- 2. Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Ruth J Muschel
- 2. Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Xiaoyuan Chen
- 3. Laboratory of Molecular Imaging and Nanomedicine (LOMIN), National Institute of Biomedical Imaging and Bioengineering (NIBIB), National Institutes of Health (NIH), Bethesda, Maryland 20892, United States
| | - Nicola R Sibson
- 2. Cancer Research UK and Medical Research Council Oxford Institute for Radiation Oncology, Department of Oncology, University of Oxford, Oxford, UK
| | - Robin P Choudhury
- 1. Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, United Kingdom
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14
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Pai S, Qin J, Cavanagh L, Mitchell A, El-Assaad F, Jain R, Combes V, Hunt NH, Grau GER, Weninger W. Real-time imaging reveals the dynamics of leukocyte behaviour during experimental cerebral malaria pathogenesis. PLoS Pathog 2014; 10:e1004236. [PMID: 25033406 PMCID: PMC4102563 DOI: 10.1371/journal.ppat.1004236] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 05/23/2014] [Indexed: 02/02/2023] Open
Abstract
During experimental cerebral malaria (ECM) mice develop a lethal neuropathological syndrome associated with microcirculatory dysfunction and intravascular leukocyte sequestration. The precise spatio-temporal context in which the intravascular immune response unfolds is incompletely understood. We developed a 2-photon intravital microscopy (2P-IVM)-based brain-imaging model to monitor the real-time behaviour of leukocytes directly within the brain vasculature during ECM. Ly6Chi monocytes, but not neutrophils, started to accumulate in the blood vessels of Plasmodium berghei ANKA (PbA)-infected MacGreen mice, in which myeloid cells express GFP, one to two days prior to the onset of the neurological signs (NS). A decrease in the rolling speed of monocytes, a measure of endothelial cell activation, was associated with progressive worsening of clinical symptoms. Adoptive transfer experiments with defined immune cell subsets in recombinase activating gene (RAG)-1-deficient mice showed that these changes were mediated by Plasmodium-specific CD8+ T lymphocytes. A critical number of CD8+ T effectors was required to induce disease and monocyte adherence to the vasculature. Depletion of monocytes at the onset of disease symptoms resulted in decreased lymphocyte accumulation, suggesting reciprocal effects of monocytes and T cells on their recruitment within the brain. Together, our studies define the real-time kinetics of leukocyte behaviour in the central nervous system during ECM, and reveal a significant role for Plasmodium-specific CD8+ T lymphocytes in regulating vascular pathology in this disease. Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection that takes a significant toll on human life. Blockage of the brain blood vessels contributes to the clinical signs of CM, however we know little about the precise pathological events that lead to this disease. To this end, studies in Plasmodium-infected mice, that also develop a similar fatal disease, have proven useful. These studies have revealed an important role for leukocytes not so much in protecting but rather promoting pathology in the brain. To better understand leukocyte behaviour during experimental CM, we established a brain-imaging model that allows us to ‘peek’ into the brain of living mice and watch immunological events as they unfold. We found that worsening of disease was accompanied by an accumulation of monocytes in the blood vessels. Monocyte accumulation was regulated by activated CD8+ T cells but only when present in critical numbers. Monocyte depletion resulted in reduced T cell trafficking to the brain, but this did not result in improved disease outcome. Our studies reveal the orchestration of leukocyte accumulation in real time during CM, and demonstrate that CD8+ T cells play a crucial role in promoting clinical signs in this disease.
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Affiliation(s)
- Saparna Pai
- Immune Imaging Laboratory, The Centenary Institute, Newtown, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- * E-mail: (SP); (WW)
| | - Jim Qin
- Immune Imaging Laboratory, The Centenary Institute, Newtown, Sydney, New South Wales, Australia
| | - Lois Cavanagh
- Immune Imaging Laboratory, The Centenary Institute, Newtown, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Andrew Mitchell
- Immune Imaging Laboratory, The Centenary Institute, Newtown, Sydney, New South Wales, Australia
| | - Fatima El-Assaad
- Vascular Immunology Unit, Discipline of Pathology, Sydney Medical School, University of Sydney, Camperdown, Sydney, New South Wales, Australia
| | - Rohit Jain
- Immune Imaging Laboratory, The Centenary Institute, Newtown, Sydney, New South Wales, Australia
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
| | - Valery Combes
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Vascular Immunology Unit, Discipline of Pathology, Sydney Medical School, University of Sydney, Camperdown, Sydney, New South Wales, Australia
| | - Nicholas H. Hunt
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Molecular Immunopathology Unit, Discipline of Pathology, Sydney Medical School and Bosch Institute, University of Sydney, Camperdown, Sydney, New South Wales, Australia
| | - Georges E. R. Grau
- Sydney Medical School, University of Sydney, Sydney, New South Wales, Australia
- Vascular Immunology Unit, Discipline of Pathology, Sydney Medical School, University of Sydney, Camperdown, Sydney, New South Wales, Australia
| | - Wolfgang Weninger
- Immune Imaging Laboratory, The Centenary Institute, Newtown, Sydney, New South Wales, Australia
- Discipline of Dermatology, University of Sydney, Sydney, New South Wales, Australia
- Department of Dermatology, Royal Prince Alfred Hospital, Camperdown, Sydney, New South Wales, Australia
- * E-mail: (SP); (WW)
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Abstract
Neuroinflammation plays a central role in a variety of neurological diseases, including stroke, multiple sclerosis, Alzheimer’s disease, and malignant CNS neoplasms, among many other. Different cell types and molecular mediators participate in a cascade of events in the brain that is ultimately aimed at control, regeneration and repair, but leads to damage of brain tissue under pathological conditions. Non-invasive molecular imaging of key players in the inflammation cascade holds promise for identification and quantification of the disease process before it is too late for effective therapeutic intervention. In this review, we focus on molecular imaging techniques that target inflammatory cells and molecules that are of interest in neuroinflammation, especially those with high translational potential. Over the past decade, a plethora of molecular imaging agents have been developed and tested in animal models of (neuro)inflammation, and a few have been translated from bench to bedside. The most promising imaging techniques to visualize neuroinflammation include MRI, positron emission tomography (PET), single photon emission computed tomography (SPECT), and optical imaging methods. These techniques enable us to image adhesion molecules to visualize endothelial cell activation, assess leukocyte functions such as oxidative stress, granule release, and phagocytosis, and label a variety of inflammatory cells for cell tracking experiments. In addition, several cell types and their activation can be specifically targeted in vivo, and consequences of neuroinflammation such as neuronal death and demyelination can be quantified. As we continue to make progress in utilizing molecular imaging technology to study and understand neuroinflammation, increasing efforts and investment should be made to bring more of these novel imaging agents from the “bench to bedside.”
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Affiliation(s)
- Benjamin Pulli
- Center for Systems Biology and Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 185 Cambridge Street, Boston, MA 02114, USA
| | - John W Chen
- Center for Systems Biology and Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 185 Cambridge Street, Boston, MA 02114, USA
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16
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Frevert U, Nacer A, Cabrera M, Movila A, Leberl M. Imaging Plasmodium immunobiology in the liver, brain, and lung. Parasitol Int 2013; 63:171-86. [PMID: 24076429 DOI: 10.1016/j.parint.2013.09.013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2012] [Revised: 08/28/2013] [Accepted: 09/18/2013] [Indexed: 01/10/2023]
Abstract
Plasmodium falciparum malaria is responsible for the deaths of over half a million African children annually. Until a decade ago, dynamic analysis of the malaria parasite was limited to in vitro systems with the typical limitations associated with 2D monocultures or entirely artificial surfaces. Due to extremely low parasite densities, the liver was considered a black box in terms of Plasmodium sporozoite invasion, liver stage development, and merozoite release into the blood. Further, nothing was known about the behavior of blood stage parasites in organs such as the brain where clinical signs manifest and the ensuing immune response of the host that may ultimately result in a fatal outcome. The advent of fluorescent parasites, advances in imaging technology, and availability of an ever-increasing number of cellular and molecular probes have helped illuminate many steps along the pathogenetic cascade of this deadly tropical parasite.
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Affiliation(s)
- Ute Frevert
- Division of Medical Parasitology, Department of Microbiology, New York University School of Medicine, 341 E 25 Street, New York, NY 10010, USA.
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17
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In vivo imaging in NHP models of malaria: challenges, progress and outlooks. Parasitol Int 2013; 63:206-15. [PMID: 24042056 PMCID: PMC7108422 DOI: 10.1016/j.parint.2013.09.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 08/30/2013] [Accepted: 09/06/2013] [Indexed: 12/22/2022]
Abstract
Animal models of malaria, mainly mice, have made a large contribution to our knowledge of host-pathogen interactions and immune responses, and to drug and vaccine design. Non-human primate (NHP) models for malaria are admittedly under-used, although they are probably closer models than mice for human malaria; in particular, NHP models allow the use of human pathogens (Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae and Plasmodium knowlesi). NHPs, whether natural hosts or experimentally challenged with a simian Plasmodium, can also serve as robust pre-clinical models. Some simian parasites are closely related to a human counterpart, with which they may share a common ancestor, and display similar major features with the human infection and pathology. NHP models allow longitudinal studies, from the early events following sporozoite inoculation to the later events, including analysis of organs and tissues, particularly liver, spleen, brain and bone marrow. NHP models have one other significant advantage over mouse models: NHPs are our closest relatives and thus their biology is very similar to ours. Recently developed in vivo imaging tools have provided insight into malaria parasite infection and disease in mouse models. One advantage of these tools is that they limit the need for invasive procedures, such as tissue biopsies. Many such technologies are now available for NHP studies and provide new opportunities for elucidating host/parasite interactions. The aim of this review is to bring the malaria community up to date on what is currently possible and what soon will be, in terms of in vivo imaging in NHP models of malaria, to consider the pros and the cons of the various techniques, and to identify challenges.
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18
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Bopp SER, Rodrigo E, González-Páez GE, Frazer M, Barnes SW, Valim C, Watson J, Walker JR, Schmedt C, Winzeler EA. Identification of the Plasmodium berghei resistance locus 9 linked to survival on chromosome 9. Malar J 2013; 12:316. [PMID: 24025732 PMCID: PMC3848760 DOI: 10.1186/1475-2875-12-316] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Accepted: 08/25/2013] [Indexed: 11/10/2022] Open
Abstract
Background One of the main causes of mortality from severe malaria in Plasmodium falciparum infections is cerebral malaria (CM). An important host genetic component determines the susceptibility of an individual to develop CM or to clear the infection and become semi-immune. As such, the identification of genetic loci associated with susceptibility or resistance may serve to modulate disease severity. Methodology The Plasmodium berghei mouse model for experimental cerebral malaria (ECM) reproduces several disease symptoms seen in human CM, and two different phenotypes, a susceptible (FVB/NJ) and a resistant mouse strain (DBA/2J), were examined. Results FVB/NJ mice died from infection within ten days, whereas DBA/2J mice showed a gender bias: males survived on average nineteen days and females either died early with signs of ECM or survived for up to three weeks. A comparison of brain pathology between FVB/NJ and DBA/2J showed no major differences with regard to brain haemorrhages or the number of parasites and CD3+ cells in the microvasculature. However, significant differences were found in the peripheral blood of infected mice: For example resistant DBA/2J mice had significantly higher numbers of circulating basophils than did FVB/NJ mice on day seven. Analysis of the F2 offspring from a cross of DBA/2J and FVB/NJ mice mapped the genetic locus of the underlying survival trait to chromosome 9 with a Lod score of 4.9. This locus overlaps with two previously identified resistance loci (char1 and pymr) from a blood stage malaria model. Conclusions Survival best distinguishes malaria infections between FVB/NJ and DBA/2J mice. The importance of char1 and pymr on chromosome 9 in malaria resistance to P. berghei was confirmed. In addition there was an association of basophil numbers with survival.
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Affiliation(s)
- Selina E R Bopp
- Department of Pediatrics, University of California, San Diego, School of Medicine, La Jolla, CA, USA.
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Martins YC, Clemmer L, Orjuela-Sánchez P, Zanini GM, Ong PK, Frangos JA, Carvalho LJM. Slow and continuous delivery of a low dose of nimodipine improves survival and electrocardiogram parameters in rescue therapy of mice with experimental cerebral malaria. Malar J 2013; 12:138. [PMID: 23617605 PMCID: PMC3642006 DOI: 10.1186/1475-2875-12-138] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Accepted: 04/14/2013] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Human cerebral malaria (HCM) is a life-threatening complication caused by Plasmodium falciparum infection that continues to be a major global health problem despite optimal anti-malarial treatment. In the experimental model of cerebral malaria (ECM) by Plasmodium berghei ANKA, bolus administration of nimodipine at high doses together with artemether, increases survival of mice with ECM. However, the dose and administration route used is associated with cardiovascular side effects such as hypotension and bradycardia in humans and mice, which could preclude its potential use as adjunctive treatment in HCM. METHODS In the present study, alternative delivery systems for nimodipine during late-stage ECM in association with artesunate were searched to define optimal protocols to achieve maximum efficacy in increasing survival in rescue therapy while causing the least cardiac side effects. The baseline electrocardiogram (ECG) and arterial pressure characteristics of uninfected control animals and of mice with ECM and its response upon rescue treatment with artesunate associated or not with nimodipine is also analysed. RESULTS Nimodipine, given at 0.5 mg/kg/day via a slow and continuous delivery system by osmotic pumps, increases survival of mice with ECM when used as adjunctive treatment to artesunate. Mice with ECM showed hypotension and ECG changes, including bradycardia and increases in PR, QRS, QTc and ST interval duration. ECM mice also show increased QTc dispersion, heart rate variability (HRV), RMSSD, low frequency (LF) and high frequency (HF) bands of the power spectrum. Both sympathetic and parasympathetic inputs to the heart were increased, but there was a predominance of sympathetic tone as demonstrated by an increased LF/HF ratio. Nimodipine potentiated bradycardia when given by bolus injection, but not when via osmotic pumps. In addition, nimodipine shortened PR duration and improved HRV, RMSSD, LF and HF powers in mice with ECM. In addition, nimodipine did not increased hypotension or decreased the speed of arterial pressure recovery when used in rescue therapy with artesunate. CONCLUSIONS These data show that slow and continuous delivery of lower doses of nimodipine improves survival of mice with ECM in rescue therapy with artesunate while showing a safer profile in terms of cardiovascular effects.
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Affiliation(s)
- Yuri C Martins
- Center for Malaria Research, La Jolla Bioengineering Institute, 3535 General Atomics Court Suite 210, 92121, San Diego, CA, USA.
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20
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von Elverfeldt D, von zur Muhlen C, Wiens K, Neudorfer I, Zirlik A, Meissner M, Tilly P, Charles AL, Bode C, Peter K, Fabre JE. In vivo detection of activated platelets allows characterizing rupture of atherosclerotic plaques with molecular magnetic resonance imaging in mice. PLoS One 2012; 7:e45008. [PMID: 23028736 PMCID: PMC3441740 DOI: 10.1371/journal.pone.0045008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Accepted: 08/11/2012] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Early and non-invasive detection of platelets on micro atherothrombosis provides a means to identify unstable plaque and thereby allowing prophylactic treatment towards prevention of stroke or myocardial infarction. Molecular magnetic resonance imaging (mMRI) of activated platelets as early markers of plaque rupture using targeted contrast agents is a promising strategy. In this study, we aim to specifically image activated platelets in murine atherothrombosis by in vivo mMRI, using a dedicated animal model of plaque rupture. METHODS An antibody targeting ligand-induced binding sites (LIBS) on the glycoprotein IIb/IIIa-receptor of activated platelets was conjugated to microparticles of iron oxide (MPIO) to form the LIBS-MPIO contrast agent causing a signal-extinction in T2*-weighted MRI. ApoE(-/-) mice (60 weeks-old) were fed a high fat diet for 5 weeks. Using a small needle, the surface of their carotid plaques was scratched under blood flow to induce atherothrombosis. In vivo 9.4 Tesla MRI was performed before and repetitively after intravenous injection of either LIBS-MPIO versus non-targeted-MPIO. RESULTS LIBS-MPIO injected animals showed a significant signal extinction (p<0.05) in MRI, corresponding to the site of plaque rupture and atherothrombosis in histology. The signal attenuation was effective for atherothrombosis occupying ≥ 2% of the vascular lumen. Histology further confirmed significant binding of LIBS-MPIO compared to control-MPIO on the thrombus developing on the surface of ruptured plaques (p<0.01). CONCLUSION in vivo mMRI detected activated platelets on mechanically ruptured atherosclerotic plaques in ApoE(-/-) mice with a high sensititvity. This imaging technology represents a unique opportunity for noninvasive detection of atherothrombosis and the identification of unstable atherosclerotic plaques with the ultimate promise to prevent strokes and myocardial infarctions.
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Affiliation(s)
| | | | - Kristina Wiens
- Department of Cardiology and Angiology I, University Heart Center, Freiburg, Germany
| | - Irene Neudorfer
- Department of Cardiology and Angiology I, University Heart Center, Freiburg, Germany
| | - Andreas Zirlik
- Department of Cardiology and Angiology I, University Heart Center, Freiburg, Germany
| | - Mirko Meissner
- Department of Radiology/Medical Physics, University Hospital, Freiburg, Germany
| | - Peg Tilly
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de Santé et de Recherche Médicale (INSERM) U964/Centre National de Recherche Scientifique (CNRS) UMR 7104/Université de Strasbourg, Illkirch, France
| | - Anne-Laure Charles
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de Santé et de Recherche Médicale (INSERM) U964/Centre National de Recherche Scientifique (CNRS) UMR 7104/Université de Strasbourg, Illkirch, France
| | - Christoph Bode
- Department of Cardiology and Angiology I, University Heart Center, Freiburg, Germany
| | | | - Jean-Etienne Fabre
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Institut National de Santé et de Recherche Médicale (INSERM) U964/Centre National de Recherche Scientifique (CNRS) UMR 7104/Université de Strasbourg, Illkirch, France
- * E-mail:
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Molecular MRI enables early and sensitive detection of brain metastases. Proc Natl Acad Sci U S A 2012; 109:6674-9. [PMID: 22451897 DOI: 10.1073/pnas.1117412109] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Metastasis to the brain is a leading cause of cancer mortality. The current diagnostic method of gadolinium-enhanced MRI is sensitive only to larger tumors, when therapeutic options are limited. Earlier detection of brain metastases is critical for improved treatment. We have developed a targeted MRI contrast agent based on microparticles of iron oxide that enables imaging of endothelial vascular cell adhesion molecule-1 (VCAM-1). Our objectives here were to determine whether VCAM-1 is up-regulated on vessels associated with brain metastases, and if so, whether VCAM-1-targeted MRI enables early detection of these tumors. Early up-regulation of cerebrovascular VCAM-1 expression was evident on tumor-associated vessels in two separate murine models of brain metastasis. Metastases were detectable in vivo using VCAM-1-targeted MRI 5 d after induction (<1,000 cells). At clinical imaging resolutions, this finding is likely to translate to detection at tumor volumes two to three orders of magnitude smaller (0.3-3 × 10(5) cells) than those volumes detectable clinically (10(7)-10(8) cells). VCAM-1 expression detected by MRI increased significantly (P < 0.0001) with tumor progression, and tumors showed no gadolinium enhancement. Importantly, expression of VCAM-1 was shown in human brain tissue containing both established metastases and micrometastases. Translation of this approach to the clinic could increase therapeutic options and change clinical management in a substantial number of cancer patients.
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Rénia L, Howland SW, Claser C, Charlotte Gruner A, Suwanarusk R, Hui Teo T, Russell B, Ng LFP. Cerebral malaria: mysteries at the blood-brain barrier. Virulence 2012; 3:193-201. [PMID: 22460644 PMCID: PMC3396698 DOI: 10.4161/viru.19013] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Cerebral malaria is the most severe pathology caused by the malaria parasite, Plasmodium falciparum. The pathogenic mechanisms leading to cerebral malaria are still poorly defined as studies have been hampered by limited accessibility to human tissues. Nevertheless, histopathology of post-mortem human tissues and mouse models of cerebral malaria have indicated involvement of the blood-brain barrier in cerebral malaria. In contrast to viruses and bacteria, malaria parasites do not infiltrate and infect the brain parenchyma. Instead, rupture of the blood-brain barrier occurs and may lead to hemorrhages resulting in neurological alterations. Here, we review the most recent findings from human studies and mouse models on the interactions of malaria parasites and the blood-brain barrier, shedding light on the pathogenesis of cerebral malaria, which may provide directions for possible interventions.
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Affiliation(s)
- Laurent Rénia
- Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A STAR), Biopolis, Singapore.
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Serres S, Mardiguian S, Campbell SJ, McAteer MA, Akhtar A, Krapitchev A, Choudhury RP, Anthony DC, Sibson NR. VCAM-1-targeted magnetic resonance imaging reveals subclinical disease in a mouse model of multiple sclerosis. FASEB J 2011; 25:4415-22. [PMID: 21908714 DOI: 10.1096/fj.11-183772] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Diagnosis of multiple sclerosis (MS) currently requires lesion identification by gadolinium (Gd)-enhanced or T(2)-weighted magnetic resonance imaging (MRI). However, these methods only identify late-stage pathology associated with blood-brain barrier breakdown. There is a growing belief that more widespread, but currently undetectable, pathology is present in the MS brain. We have previously demonstrated that an anti-VCAM-1 antibody conjugated to microparticles of iron oxide (VCAM-MPIO) enables in vivo detection of VCAM-1 by MRI. Here, in an experimental autoimmune encephalomyelitis (EAE) mouse model of MS, we have shown that presymptomatic lesions can be quantified using VCAM-MPIO when they are undetectable by Gd-enhancing MRI. Moreover, in symptomatic animals VCAM-MPIO binding was present in all regions showing Gd-DTPA enhancement and also in areas of no Gd-DTPA enhancement, which were confirmed histologically to be regions of leukocyte infiltration. VCAM-MPIO binding correlated significantly with increasing disability. Negligible MPIO-induced contrast was found in either EAE animals injected with an equivalent nontargeted contrast agent (IgG-MPIO) or in control animals injected with the VCAM-MPIO. These findings describe a highly sensitive molecular imaging tool that may enable detection of currently invisible pathology in MS, thus accelerating diagnosis, guiding treatment, and enabling quantitative disease assessment.
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Affiliation(s)
- Sébastien Serres
- Cancer Research UK/Medical Research Council Gray Institute for Radiation Oncology and Biology, Department of Oncology, Churchill Hospital, Oxford, OX3 7LJ, UK
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24
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Cromer Berman SM, Walczak P, Bulte JWM. Tracking stem cells using magnetic nanoparticles. WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY 2011; 3:343-55. [PMID: 21472999 DOI: 10.1002/wnan.140] [Citation(s) in RCA: 174] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Stem cell therapies offer great promise for many diseases, especially those without current effective treatments. It is believed that noninvasive imaging techniques, which offer the ability to track the status of cells after transplantation, will expedite progress in this field and help to achieve maximized therapeutic effect. Today's biomedical imaging technology allows for real-time, noninvasive monitoring of grafted stem cells including their biodistribution, migration, survival, and differentiation, with magnetic resonance imaging (MRI) of nanoparticle-labeled cells being one of the most commonly used techniques. Among the advantages of MR cell tracking are its high spatial resolution, no exposure to ionizing radiation, and clinical applicability. In order to track cells by MRI, the cells need to be labeled with magnetic nanoparticles, for which many types exist. There are several cellular labeling techniques available, including simple incubation, use of transfection agents, magnetoelectroporation, and magnetosonoporation. In this overview article, we will review the use of different magnetic nanoparticles and discuss how these particles can be used to track the distribution of transplanted cells in different organ systems. Caveats and limitations inherent to the tracking of nanoparticle-labeled stem cells are also discussed.
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Affiliation(s)
- Stacey M Cromer Berman
- Division of MR Research, Russell H. Morgan Department of Radiology and Radiological Science, Cellular Imaging Section and Vascular Biology Program, Institute for Cell Engineering, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
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25
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Srivastava K, Field DJ, Aggrey A, Yamakuchi M, Morrell CN. Platelet factor 4 regulation of monocyte KLF4 in experimental cerebral malaria. PLoS One 2010; 5:e10413. [PMID: 20454664 PMCID: PMC2862712 DOI: 10.1371/journal.pone.0010413] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Accepted: 04/08/2010] [Indexed: 11/19/2022] Open
Abstract
Cerebral malaria continues to be a difficult to treat complication of Plasmodium falciparum infection in children. We have shown that platelets can have major deleterious immune functions in experimental cerebral malaria (ECM). One of the platelet derived mediators we have identified as particularly important is platelet factor 4/CXCL4. Our prior work demonstrated that PF4(-/-) mice are protected from ECM, have reduced plasma cytokines, and have reduced T-cell trafficking to the brain. We now show that PF4 drives monocyte cytokine production in a Kruppel like factor 4 (KLF4) dependent manner. Monocyte depleted Plasmodium berghei infected mice have improved survival, and KLF4 is greatly increased in control, but not monocyte depleted mice. PF4(-/-) mice have less cerebral monocyte trafficking and no change in KLF4 expression. These data indicate that PF4 induction of monocyte KLF4 expression may be an important step in the pathogenesis of ECM.
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Affiliation(s)
- Kalyan Srivastava
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - David J. Field
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Angela Aggrey
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Munekazu Yamakuchi
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Craig N. Morrell
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
- * E-mail:
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26
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Cox D, McConkey S. The role of platelets in the pathogenesis of cerebral malaria. Cell Mol Life Sci 2010; 67:557-68. [PMID: 20091081 PMCID: PMC11115904 DOI: 10.1007/s00018-009-0211-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2009] [Accepted: 11/05/2009] [Indexed: 01/31/2023]
Abstract
Malaria is a major cause of morbidity and mortality in the developing world and cerebral malaria is responsible for the majority of malaria-associated deaths. There is a strong association between thrombocytopenia and outcome in malaria, suggesting a role for platelets in the pathogenesis of malaria. This thrombocytopenia is likely due to platelet activation possibly through an interaction between PfEMP1 on plasmodium and CD36 on platelets. Platelet activation by plasmodium has two potential consequences. It can lead to the formation of micro-aggregates of infected red blood cells and platelets which can occlude blood vessels and it also leads to binding to and activation of the endothelium.
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Affiliation(s)
- Dermot Cox
- Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland, 123 St Stephens Green, Dublin 2, Ireland.
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27
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Mishra SK, Newton CRJC. Diagnosis and management of the neurological complications of falciparum malaria. Nat Rev Neurol 2009; 5:189-98. [PMID: 19347024 PMCID: PMC2859240 DOI: 10.1038/nrneurol.2009.23] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Malaria is a major public health problem in the developing world owing to its high rates of morbidity and mortality. Of all the malarial parasites that infect humans, Plasmodium falciparum is most commonly associated with neurological complications, which manifest as agitation, psychosis, seizures, impaired consciousness and coma (cerebral malaria). Cerebral malaria is the most severe neurological complication; the condition is associated with mortality of 15-20%, and a substantial proportion of individuals with this condition develop neurocognitive sequelae. In this Review, we describe the various neurological complications encountered in malaria, discuss the underlying pathogenesis, and outline current management strategies for these complications. Furthermore, we discuss the role of adjunctive therapies in improving outcome.
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28
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Choudhury RP, Fisher EA. Molecular imaging in atherosclerosis, thrombosis, and vascular inflammation. Arterioscler Thromb Vasc Biol 2009; 29:983-91. [PMID: 19213945 DOI: 10.1161/atvbaha.108.165498] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Appreciation of the molecular and cellular processes of atherosclerosis, thrombosis, and vascular inflammation has identified new targets for imaging. The common goals of molecular imaging approaches are to accelerate and refine diagnosis, provide insights that reveal disease diversity, guide specific therapies, and monitor the effects of those therapies. Here we undertake a comparative analysis of imaging modalities that have been used in this disease area. We consider the elements of contrast agents, emphasizing how an understanding of the biology of atherosclerosis and its complications can inform optimal design. We address the potential and limitations of current contrast approaches in respect of translation to clinically usable agents and speculate on future applications.
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29
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Platelet factor 4 mediates inflammation in experimental cerebral malaria. Cell Host Microbe 2008; 4:179-87. [PMID: 18692777 DOI: 10.1016/j.chom.2008.07.003] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2007] [Revised: 05/20/2008] [Accepted: 07/11/2008] [Indexed: 11/23/2022]
Abstract
Cerebral malaria (CM) is a major complication of Plasmodium falciparum infection in children. The pathogenesis of CM involves vascular inflammation, immune stimulation, and obstruction of cerebral capillaries. Platelets have a prominent role in both immune responses and vascular obstruction. We now demonstrate that the platelet-derived chemokine, platelet factor 4 (PF4)/CXCL4, promotes the development of experimental cerebral malaria (ECM). Plasmodium-infected red blood cells (RBCs) activated platelets independently of vascular effects, resulting in increased plasma PF4. PF4 or chemokine receptor CXCR3 null mice had less severe ECM, including decreased T cell recruitment to the brain, and platelet depletion or aspirin treatment reduced the development of ECM. We conclude that Plasmodium-infected RBCs can directly activate platelets, and platelet-derived PF4 then contributes to immune activation and T cell trafficking as part of the pathogenesis of ECM.
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30
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Togbe D, Loureiro de Sousa P, Fauconnier M, Boissay V, Fick L, Scheu S, Pfeffer K, Menard R, Grau GE, Doan BT, Beloeil JC, Renia L, Hansen AM, Ball HJ, Hunt NH, Ryffel B, Quesniaux VFJ. Both functional LTbeta receptor and TNF receptor 2 are required for the development of experimental cerebral malaria. PLoS One 2008; 3:e2608. [PMID: 18612394 PMCID: PMC2442868 DOI: 10.1371/journal.pone.0002608] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 06/04/2008] [Indexed: 12/19/2022] Open
Abstract
Background TNF-related lymphotoxin α (LTα) is essential for the development of Plasmodium berghei ANKA (PbA)-induced experimental cerebral malaria (ECM). The pathway involved has been attributed to TNFR2. Here we show a second arm of LTα-signaling essential for ECM development through LTβ-R, receptor of LTα1β2 heterotrimer. Methodology/Principal Findings LTβR deficient mice did not develop the neurological signs seen in PbA induced ECM but died at three weeks with high parasitaemia and severe anemia like LTαβ deficient mice. Resistance of LTαβ or LTβR deficient mice correlated with unaltered cerebral microcirculation and absence of ischemia, as documented by magnetic resonance imaging and angiography, associated with lack of microvascular obstruction, while wild-type mice developed distinct microvascular pathology. Recruitment and activation of perforin+ CD8+ T cells, and their ICAM-1 expression were clearly attenuated in the brain of resistant mice. An essential contribution of LIGHT, another LTβR ligand, could be excluded, as LIGHT deficient mice rapidly succumbed to ECM. Conclusions/Significance LTβR expressed on radioresistant resident stromal, probably endothelial cells, rather than hematopoietic cells, are essential for the development of ECM, as assessed by hematopoietic reconstitution experiment. Therefore, the data suggest that both functional LTβR and TNFR2 signaling are required and non-redundant for the development of microvascular pathology resulting in fatal ECM.
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Affiliation(s)
- Dieudonnée Togbe
- University of Orléans and CNRS, Molecular Immunology and Embryology UMR6218, Orleans, France
| | | | - Mathilde Fauconnier
- University of Orléans and CNRS, Molecular Immunology and Embryology UMR6218, Orleans, France
| | - Victorine Boissay
- University of Orléans and CNRS, Molecular Immunology and Embryology UMR6218, Orleans, France
| | - Lizette Fick
- Institute of Infectious Disease and Molecular Medicine, Cape Town, South Africa
| | | | | | | | - Georges E. Grau
- The University of Sydney, Department of Pathology, Camperdown, Australia
| | - Bich-Thuy Doan
- CNRS CBM (Centre de Biophysique Moléculaire), Orleans, France
| | | | - Laurent Renia
- The University of Sydney, Department of Pathology, Camperdown, Australia
- Inserm, U567, Paris, France
| | - Anna M. Hansen
- The University of Sydney, Department of Pathology, Camperdown, Australia
| | - Helen J. Ball
- The University of Sydney, Department of Pathology, Camperdown, Australia
| | - Nicholas H. Hunt
- The University of Sydney, Department of Pathology, Camperdown, Australia
| | - Bernhard Ryffel
- University of Orléans and CNRS, Molecular Immunology and Embryology UMR6218, Orleans, France
- * E-mail: (BR); (VQ)
| | - Valerie F. J. Quesniaux
- University of Orléans and CNRS, Molecular Immunology and Embryology UMR6218, Orleans, France
- * E-mail: (BR); (VQ)
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