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Bo Y, Lu Q, Li B, Sha R, Yu H, Miao C. The role of platelets in central hubs of inflammation: A literature review. Medicine (Baltimore) 2024; 103:e38115. [PMID: 38728509 PMCID: PMC11081549 DOI: 10.1097/md.0000000000038115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Accepted: 04/12/2024] [Indexed: 05/12/2024] Open
Abstract
Platelets are increasingly recognized for their multifaceted roles in inflammation beyond their traditional involvement in haemostasis. This review consolidates knowledge on platelets as critical players in inflammatory responses. This study did an extensive search of electronic databases and identified studies on platelets in inflammation, focusing on molecular mechanisms, cell interactions, and clinical implications, emphasizing recent publications. Platelets contribute to inflammation via surface receptors, release of mediators, and participation in neutrophil extracellular trap formation. They are implicated in diseases like atherosclerosis, rheumatoid arthritis, and sepsis, highlighting their interaction with immune cells as pivotal in the onset and resolution of inflammation. Platelets are central to regulating inflammation, offering new therapeutic targets for inflammatory diseases. Future research should explore specific molecular pathways of platelets in inflammation for therapeutic intervention.
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Affiliation(s)
- Yan Bo
- College of Medicine, Northwest Minzu University, Lanzhou, China
| | - Qingyang Lu
- School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR of China
| | - Beilei Li
- Department of Rehabilitation Medicine, Shanghai Xuhui Central Hospital, Shanghai, China
| | - Ren Sha
- School of Economics and Management, Henan Polytechnic University, Jiaozuo, China
| | - Haodong Yu
- School of Economic Crime Investigation, Jiangxi Police Academy, Nanchang, China
| | - Chuhan Miao
- School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong SAR of China
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2
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Ippolito MM, Kabuya JBB, Hauser M, Kamavu LK, Banda PM, Yanek LR, Malik R, Mulenga M, Bailey JA, Chongwe G, Louis TA, Shapiro TA, Moss WJ. Whole Blood Transfusion for Severe Malarial Anemia in a High Plasmodium falciparum Transmission Setting. Clin Infect Dis 2022; 75:1893-1902. [PMID: 35439307 PMCID: PMC10200327 DOI: 10.1093/cid/ciac304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Severe malaria resulting from Plasmodium falciparum infection is the leading parasitic cause of death in children worldwide, and severe malarial anemia (SMA) is the most common clinical presentation. The evidence in support of current blood transfusion guidelines for patients with SMA is limited. METHODS We conducted a retrospective cohort study of 911 hospitalized children with SMA in a holoendemic region of Zambia to examine the association of whole blood transfusion with in-hospital survival. Data were analyzed in adjusted logistic regression models using multiple imputation for missing data. RESULTS The median age of patients was 24 months (interquartile range, 16-30) and overall case fatality was 16%. Blood transfusion was associated with 35% reduced odds of death in children with SMA (odds ratio, 0.65; 95% confidence interval, .52-.81; P = .0002) corresponding to a number-needed-to-treat (NNT) of 14 patients. Children with SMA complicated by thrombocytopenia were more likely to benefit from transfusion than those without thrombocytopenia (NNT = 5). Longer storage time of whole blood was negatively associated with survival and with the posttransfusion rise in the platelet count but was not associated with the posttransfusion change in hemoglobin concentration. CONCLUSIONS Whole blood given to pediatric patients with SMA was associated with improved survival, mainly among those with thrombocytopenia who received whole blood stored for <4 weeks. These findings point to a potential use for incorporating thrombocytopenia into clinical decision making and management of severe malaria, which can be further assessed in prospective studies, and underline the importance of maintaining reliable blood donation networks in areas of high malaria transmission.
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Affiliation(s)
- Matthew M Ippolito
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- The Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jean-Bertin B Kabuya
- Department of Clinical Sciences, Tropical Diseases Research Centre, Ndola, Zambia
| | - Manuela Hauser
- Faculty of Medicine, University of Basel, Basel, Switzerland
- Children’s Research Center, University Children’s Hospital, Zurich, Switzerland
| | - Luc K Kamavu
- Saint Paul’s General Hospital, Nchelenge, Luapula Province, Zambia
| | | | - Lisa R Yanek
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Rubab Malik
- Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Modest Mulenga
- Directorate of Research and Postgraduate Studies, Lusaka Apex Medical University, Lusaka, Zambia
| | - Jeffrey A Bailey
- Department of Pathology and Laboratory Medicine, Brown University Warren Alpert Medical School, Providence, Rhode Island, USA
| | - Gershom Chongwe
- Department of Clinical Sciences, Tropical Diseases Research Centre, Ndola, Zambia
| | - Thomas A Louis
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Theresa A Shapiro
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- The Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - William J Moss
- The Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
- Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
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3
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Öztosun B, Pirdal BZ, Çınar Özel S, Kaçar AG, Apak H, Celkan T. Effect of platelet count and platelet transfusion on fever duration in patients with febrile neutropenia. Pediatr Hematol Oncol 2022; 39:736-746. [PMID: 35855637 DOI: 10.1080/08880018.2022.2066236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Platelets play a role in hemostasis, thrombosis, and vascular integrity. They also play a major role in the development of inflammation and the activation of immune responses. They have phagocytic activity, stimulate the secretion of immune modulators, and activate other immune cells, which results in platelet-neutrophil aggregation, platelet-induced neutrophil degranulation, and the formation of neutrophil extracellular traps. Data on 124 febrile neutropenia attacks were retrospectively examined. Patients' age, sex, diagnosis, and relapse history were obtained. The complete blood count levels on the first and last febrile day of the febrile neutropenia attacks, duration of fever, and number, type, and timing of thrombocyte suspension transfusions were recorded. The patients were divided into three groups according to the day of fever when the platelet suspension was administered (1 day, 2-3 days, and >3 days); the duration of fever was compared between the three groups. The fever duration of those who were transfused with platelet suspension on the first day of fever was found to be significantly shorter (p = 0.03 and p < 0.001, respectively). When treating a patient with febrile neutropenia, if thrombocyte suspension transfusion is indicated, transfusing thrombocytes in the first days of fever shortens the fever duration and improves the prognosis of febrile neutropenia attack, supporting the hypothesis that not only neutrophils but also platelets may play a role in fighting against microorganisms.
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Affiliation(s)
- Berrak Öztosun
- Department of Pediatrics, İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, İstanbul, Turkey
| | - Betül Zehra Pirdal
- Department of Public Health, İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, İstanbul, Turkey
| | - Simge Çınar Özel
- Division of Pediatric Hematology-Oncology, Department of Pediatrics, İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, İstanbul, Turkey
| | - Ayşe Gonca Kaçar
- Division of Pediatric Hematology-Oncology, Department of Pediatrics, İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, İstanbul, Turkey
| | - Hilmi Apak
- Division of Pediatric Hematology-Oncology, Department of Pediatrics, İstanbul University-Cerrahpaşa, Cerrahpaşa Faculty of Medicine, İstanbul, Turkey
| | - Tiraje Celkan
- Division of Pediatric Hematology-Oncology, Department of Pediatrics, İstinye University- Faculty of Medicine, İstanbul, Turkey
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4
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Nwonuma CO, Atanu FO, Okonkwo NC, Egharevba GO, Udofia IA, Evbuomwan IO, Alejolowo OO, Osemwegie OO, Adelani-Akande T, Dogunro FA. Evaluation of anti-malarial activity and GC–MS finger printing of cannabis: An in-vivo and in silico approach. SCIENTIFIC AFRICAN 2022. [DOI: 10.1016/j.sciaf.2022.e01108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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5
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Uncomplicated Plasmodium vivax malaria: mapping the proteome from circulating platelets. Clin Proteomics 2022; 19:1. [PMID: 34991449 PMCID: PMC8903537 DOI: 10.1186/s12014-021-09337-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 12/21/2021] [Indexed: 01/07/2023] Open
Abstract
Background Thrombocytopenia is frequent in Plasmodium vivax malaria but the role of platelets in pathogenesis is unknown. Our study explores the platelet (PLT) proteome from uncomplicated P. vivax patients, to fingerprint molecular pathways related to platelet function. Plasma levels of Platelet factor 4 (PF4/CXCL4) and Von Willebrand factor (VWf), as well as in vitro PLTs—P. vivax infected erythrocytes (Pv-IEs) interactions were also evaluated to explore the PLT response and effect on parasite development. Methods A cohort of 48 patients and 25 healthy controls were enrolled. PLTs were purified from 5 patients and 5 healthy controls for Liquid Chromatography–Mass spectrometry (LC–MS/MS) analysis. Plasma levels of PF4/CXCL4 and VWf were measured in all participants. Additionally, P. vivax isolates (n = 10) were co-cultured with PLTs to measure PLT activation by PF4/CXCL4 and Pv-IE schizonts formation by light microscopy. Results The proteome from uncomplicated P. vivax patients showed 26 out of 215 proteins significantly decreased. PF4/CXCL4 was significantly decreased followed by other proteins involved in platelet activation, cytoskeletal remodeling, and endothelial adhesion, including glycoprotein V that was significantly decreased in thrombocytopenic patients. In contrast, acute phase proteins, including SERPINs and Amyloid Serum A1 were increased. High levels of VWf in plasma from patients suggested endothelial activation while PF4/CXCL4 plasma levels were similar between patients and controls. Interestingly, high levels of PF4/CXCL4 were released from PLTs—Pv-IEs co-cultures while Pv-IEs schizont formation was inhibited. Conclusions The PLT proteome analyzed in this study suggests that PLTs actively respond to P. vivax infection. Altogether, our findings suggest important roles of PF4/CXCL4 during uncomplicated P. vivax infection through a possible intracellular localization. Our study shows that platelets are active responders to P. vivax infection, inhibiting intraerythrocytic parasite development. Future studies are needed to further investigate the molecular pathways of interaction between platelet proteins found in this study and host response, which could affect parasite control as well as disease progression. Supplementary Information The online version contains supplementary material available at 10.1186/s12014-021-09337-7.
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6
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Prusty D, Gupta N, Upadhyay A, Dar A, Naik B, Kumar N, Prajapati VK. Asymptomatic malaria infection prevailing risks for human health and malaria elimination. INFECTION GENETICS AND EVOLUTION 2021; 93:104987. [PMID: 34216796 DOI: 10.1016/j.meegid.2021.104987] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 06/23/2021] [Accepted: 06/27/2021] [Indexed: 01/09/2023]
Abstract
There has been a consistent rise in malaria cases in the last few years. The existing malaria control measures are challenged by insecticide resistance in the mosquito vector, drug résistance in parasite populations, and asymptomatic malaria (ASM) in healthy individuals. The absence of apparent malaria symptoms and the presence of low parasitemia makes ASM a hidden reservoir for malaria transmission and an impediment in malaria elimination efforts. This review focuses on ASM in malaria-endemic countries and the past and present research trends from those geographical locations. The harmful impacts of asymptomatic malaria on human health and its contribution to disease transmission are highlighted. We discuss certain crucial genetic changes in the parasite and host immune response necessary for maintaining low parasitemia leading to long-term parasite survival in the host. Since the chronic health effects and the potential roles for disease transmission of ASM remain mostly unknown to significant populations, we offer proposals for developing general awareness. We also suggest advanced technology-based diagnostic methods, and treatment strategies to eliminate ASM.
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Affiliation(s)
- Dhaneswar Prusty
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India.
| | - Nidhi Gupta
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
| | - Arun Upadhyay
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
| | - Ashraf Dar
- Department of Biochemistry, University of Kashmir, Hazaratbal, Srinagar 190006, Jammu and Kashmir, India
| | - Biswajit Naik
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
| | - Navin Kumar
- School of Biotechnology, Gautam Buddha University, Greater Noida, 201308, UP, India
| | - Vijay Kumar Prajapati
- Department of Biochemistry, School of Life Sciences, Central University of Rajasthan, Bandarsindri, Kishangarh, Ajmer, 305817, Rajasthan, India
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7
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Whole blood transfusion improves vascular integrity and increases survival in artemether-treated experimental cerebral malaria. Sci Rep 2021; 11:12077. [PMID: 34103601 PMCID: PMC8187502 DOI: 10.1038/s41598-021-91499-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/25/2021] [Indexed: 01/28/2023] Open
Abstract
Pathological features observed in both human and experimental cerebral malaria (ECM) are endothelial dysfunction and changes in blood components. Blood transfusion has been routinely used in patients with severe malarial anemia and can also benefit comatose and acidotic malaria patients. In the present study Plasmodium berghei-infected mice were transfused intraperitoneally with 200 μL of whole blood along with 20 mg/kg of artemether. ECM mice showed severe thrombocytopenia and decreases in hematocrit. Artemether treatment markedly aggravated anemia within 24 h. Whole blood administration significantly prevented further drop in hematocrit and partially restored the platelet count. Increased levels of plasma angiopoietin-2 (Ang-2) remained high 24 h after artemether treatment but returned to normal levels 24 h after blood transfusion, indicating reversal to quiescence. Ang-1 was depleted in ECM mice and levels were not restored by any treatment. Blood transfusion prevented the aggravation of the breakdown of blood brain barrier after artemether treatment and decreased spleen congestion without affecting splenic lymphocyte populations. Critically, blood transfusion resulted in markedly improved survival of mice with ECM (75.9% compared to 50.9% receiving artemether only). These findings indicate that whole blood transfusion can be an effective adjuvant therapy for cerebral malaria.
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8
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Platelet α-granules contribute to organ-specific pathologies in a mouse model of severe malaria. Blood Adv 2021; 4:1-8. [PMID: 31891656 DOI: 10.1182/bloodadvances.2019000773] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 11/19/2019] [Indexed: 12/17/2022] Open
Abstract
Key PointsNbeal2 deficiency leads to significantly reduced lung and brain pathology and enhanced survival in a mouse model of malaria. Both antibody-dependent and antibody-independent platelet depletion in mice recapitulate the findings observed in Nbeal2−/− mice.
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9
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Jongruamklang P, Rebetz J, Kapur R, Persson KEM, Olsson ML, Semple JW, Storry JR. Platelets inhibit erythrocyte invasion by Plasmodium falciparum at physiological platelet:erythrocyte ratios. Transfus Med 2021; 32:168-174. [PMID: 33987889 DOI: 10.1111/tme.12791] [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: 02/21/2020] [Revised: 10/05/2020] [Accepted: 12/27/2020] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To evaluate the effect of platelet:erythrocyte (P:E) ratios on Plasmodium falciparum erythrocyte invasion. BACKGROUND Recent reports have shown that platelets are directly involved in the immune response towards P. falciparum during erythrocyte invasion. However, the literature both supports and conflicts with a role for platelets in limiting invasion. Also, the effect of platelet numbers on invasion (parasitemia) has not been thoroughly investigated. METHODS/MATERIALS The P. falciparum strains FCR3S1.2 and W2mef were cultured with group O erythrocytes. The cultures were synchronised and supplemented with pooled platelets at P:E ratios ranging from 1:100 to 1:2. Parasitemia was measured at 40 h by flow cytometry and by microscopy of blood smears. RESULTS A linear relationship was observed between reduced invasion and increased platelet numbers at P:E ratios ranging from 1:100 to 1:20. However, this effect was reversed at lower ratios (1:10-1:2). Microscopic evaluation revealed aggregation and attachment of platelets to erythrocytes, but not specifically to parasitised erythrocytes. CONCLUSION We have shown that under physiological P:E ratios (approx. 1:10-1:40), platelets inhibited P. falciparum invasion in a dose-dependent manner. At ratios of 1:10 and below, platelets did not further increase the inhibitory effect and, although the trend was reversed, inhibition was still maintained.
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Affiliation(s)
- Philaiphon Jongruamklang
- Department of Laboratory Medicine, Division of Hematology and Transfusion Medicine, Lund University, Lund, Sweden.,Department of Medical Technology, School of Allied Health Sciences, University of Phayao, Phayao, Thailand
| | - Johan Rebetz
- Department of Laboratory Medicine, Division of Hematology and Transfusion Medicine, Lund University, Lund, Sweden
| | - Rick Kapur
- Department of Experimental Immunohematology, Sanquin Research, Amsterdam, The Netherlands.,Landsteiner Laboratory, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Kristina E M Persson
- Department of Laboratory Medicine, Division of Clinical Chemistry and Pharmacology, Lund University, Lund, Sweden.,Clinical Chemistry and Pharmacology, Laboratory Medicine, Office for Medical Services, Region Skåne, Lund, Sweden
| | - Martin L Olsson
- Department of Laboratory Medicine, Division of Hematology and Transfusion Medicine, Lund University, Lund, Sweden.,Clinical Immunology and Transfusion Medicine, Laboratory Medicine, Office for Medical Services, Region Skåne, Lund, Sweden
| | - John W Semple
- Department of Laboratory Medicine, Division of Hematology and Transfusion Medicine, Lund University, Lund, Sweden.,Clinical Immunology and Transfusion Medicine, Laboratory Medicine, Office for Medical Services, Region Skåne, Lund, Sweden
| | - Jill R Storry
- Department of Laboratory Medicine, Division of Hematology and Transfusion Medicine, Lund University, Lund, Sweden.,Clinical Immunology and Transfusion Medicine, Laboratory Medicine, Office for Medical Services, Region Skåne, Lund, Sweden
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10
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Dib PRB, Quirino-Teixeira AC, Merij LB, Pinheiro MBM, Rozini SV, Andrade FB, Hottz ED. Innate immune receptors in platelets and platelet-leukocyte interactions. J Leukoc Biol 2020; 108:1157-1182. [PMID: 32779243 DOI: 10.1002/jlb.4mr0620-701r] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 06/11/2020] [Accepted: 06/28/2020] [Indexed: 12/14/2022] Open
Abstract
Platelets are chief cells in hemostasis. Apart from their hemostatic roles, platelets are major inflammatory effector cells that can influence both innate and adaptive immune responses. Activated platelets have thromboinflammatory functions linking hemostatic and immune responses in several physiological and pathological conditions. Among many ways in which platelets exert these functions, platelet expression of pattern recognition receptors (PRRs), including TLR, Nod-like receptor, and C-type lectin receptor families, plays major roles in sensing and responding to pathogen-associated or damage-associated molecular patterns (PAMPs and DAMPs, respectively). In this review, an increasing body of evidence is compiled showing the participation of platelet innate immune receptors, including PRRs, in infectious diseases, sterile inflammation, and cancer. How platelet recognition of endogenous DAMPs participates in sterile inflammatory diseases and thrombosis is discussed. In addition, platelet recognition of both PAMPs and DAMPs initiates platelet-mediated inflammation and vascular thrombosis in infectious diseases, including viral, bacterial, and parasite infections. The study also focuses on the involvement of innate immune receptors in platelet activation during cancer, and their contribution to tumor microenvironment development and metastasis. Finally, how innate immune receptors participate in platelet communication with leukocytes, modulating leukocyte-mediated inflammation and immune functions, is highlighted. These cell communication processes, including platelet-induced release of neutrophil extracellular traps, platelet Ag presentation to T-cells and platelet modulation of monocyte cytokine secretion are discussed in the context of infectious and sterile diseases of major concern in human health, including cardiovascular diseases, dengue, HIV infection, sepsis, and cancer.
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Affiliation(s)
- Paula Ribeiro Braga Dib
- Laboratory of Immunothrombosis, Department of Biochemistry, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil.,Laboratory of Immunology, Infectious Diseases and Obesity, Department of Parasitology, Microbiology and Immunology, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Anna Cecíllia Quirino-Teixeira
- Laboratory of Immunothrombosis, Department of Biochemistry, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Laura Botelho Merij
- Laboratory of Immunothrombosis, Department of Biochemistry, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Mariana Brandi Mendonça Pinheiro
- Laboratory of Immunothrombosis, Department of Biochemistry, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Stephane Vicente Rozini
- Laboratory of Immunothrombosis, Department of Biochemistry, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Fernanda Brandi Andrade
- Laboratory of Immunothrombosis, Department of Biochemistry, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
| | - Eugenio Damaceno Hottz
- Laboratory of Immunothrombosis, Department of Biochemistry, Institute of Biological Sciences, Federal University of Juiz de Fora, Juiz de Fora, Brazil
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11
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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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12
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Sierro F, Grau GER. The Ins and Outs of Cerebral Malaria Pathogenesis: Immunopathology, Extracellular Vesicles, Immunometabolism, and Trained Immunity. Front Immunol 2019; 10:830. [PMID: 31057552 PMCID: PMC6478768 DOI: 10.3389/fimmu.2019.00830] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2018] [Accepted: 03/28/2019] [Indexed: 12/16/2022] Open
Abstract
Complications from malaria parasite infections still cost the lives of close to half a million people every year. The most severe is cerebral malaria (CM). Employing murine models of CM, autopsy results, in vitro experiments, neuroimaging and microscopic techniques, decades of research activity have investigated the development of CM immunopathology in the hope of identifying steps that could be therapeutically targeted. Yet important questions remain. This review summarizes recent findings, primarily mechanistic insights on the essential cellular and molecular players involved gained within the murine experimental cerebral malaria model. It also highlights recent developments in (a) cell-cell communication events mediated through extracellular vesicles (EVs), (b) mounting evidence for innate immune memory, leading to “trained“ increased or tolerised responses, and (c) modulation of immune cell function through metabolism, that could shed light on why some patients develop this life-threatening condition whilst many do not.
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Affiliation(s)
- Frederic Sierro
- Vascular Immunology Unit, Department of Pathology, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Sydney, NSW, Australia.,Human Health, Nuclear Science, Technology, and Landmark Infrastructure, Australian Nuclear Science and Technology Organisation, Sydney, NSW, Australia
| | - Georges E R Grau
- Vascular Immunology Unit, Department of Pathology, Faculty of Medicine and Health, School of Medical Sciences, The University of Sydney, Sydney, NSW, Australia
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13
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Xiong-Hang K, Kemnetz-Ness K, Krieger AC, Haynes CL. Insight into the Effects of Plasmodium chabaudi on Platelets Using Carbon-Fiber Microelectrode Amperometry. ACS Infect Dis 2019; 5:592-597. [PMID: 30712339 DOI: 10.1021/acsinfecdis.8b00334] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Platelets are anuclear circulating cell bodies within the bloodstream commonly known for their roles in clot formation during vascular injury to prevent blood loss. They also have significant impact in a range of diseases, including malaria. However, the role of platelets in malaria is controversial, with contradicting evidence suggesting either that they assist in destruction of malarial parasites or facilitate a severe form of malaria. Precedent work suggests that the timing of infection is critical in determining whether platelets switch roles from being protective to deleterious. As such, the work herein makes use of the unique mechanistic perspective offered by carbon-fiber microelectrode amperometry (CFMA) to understand how platelet secretion is impacted in malarial infection stages (ascending parasite count versus descending parasite count). Malarial platelet behavior was compared to platelets from noninfected control mice by probing their exocytotic function. Results suggest that mouse malaria caused by the parasite Plasmodium chabaudi, during both ascending and descending infection stages, reduces platelet exocytotic events and delays platelet granule fusion; in addition, platelets are more impacted by the disease early in the infection stages. In all, understanding platelet behavior in the malarial context may present new therapeutic routes to treat or cure malaria.
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Affiliation(s)
- Kang Xiong-Hang
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Kaila Kemnetz-Ness
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Anna C. Krieger
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
| | - Christy L. Haynes
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, United States
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Rondina MT, Zimmerman GA. The Role of Platelets in Inflammation. Platelets 2019. [DOI: 10.1016/b978-0-12-813456-6.00028-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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15
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The Role of Platelets in Antimicrobial Host Defense. Platelets 2019. [DOI: 10.1016/b978-0-12-813456-6.00029-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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16
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Kho S, Barber BE, Johar E, Andries B, Poespoprodjo JR, Kenangalem E, Piera KA, Ehmann A, Price RN, William T, Woodberry T, Foote S, Minigo G, Yeo TW, Grigg MJ, Anstey NM, McMorran BJ. Platelets kill circulating parasites of all major Plasmodium species in human malaria. Blood 2018; 132:1332-1344. [PMID: 30026183 PMCID: PMC6161646 DOI: 10.1182/blood-2018-05-849307] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 06/27/2018] [Indexed: 01/12/2023] Open
Abstract
Platelets are understood to assist host innate immune responses against infection, although direct evidence of this function in any human disease, including malaria, is unknown. Here we characterized platelet-erythrocyte interactions by microscopy and flow cytometry in patients with malaria naturally infected with Plasmodium falciparum, Plasmodium vivax, Plasmodium malariae, or Plasmodium knowlesi Blood samples from 376 participants were collected from malaria-endemic areas of Papua, Indonesia, and Sabah, Malaysia. Platelets were observed binding directly with and killing intraerythrocytic parasites of each of the Plasmodium species studied, particularly mature stages, and was greatest in P vivax patients. Platelets preferentially bound to the infected more than to the uninfected erythrocytes in the bloodstream. Analysis of intraerythrocytic parasites indicated the frequent occurrence of platelet-associated parasite killing, characterized by the intraerythrocytic accumulation of platelet factor-4 and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick-end labeling of parasite nuclei (PF4+TUNEL+ parasites). These PF4+TUNEL+ parasites were not associated with measures of systemic platelet activation. Importantly, patient platelet counts, infected erythrocyte-platelet complexes, and platelet-associated parasite killing correlated inversely with patient parasite loads. These relationships, taken together with the frequency of platelet-associated parasite killing observed among the different patients and Plasmodium species, suggest that platelets may control the growth of between 5% and 60% of circulating parasites. Platelet-erythrocyte complexes made up a major proportion of the total platelet pool in patients with malaria and may therefore contribute considerably to malarial thrombocytopenia. Parasite killing was demonstrated to be platelet factor-4-mediated in P knowlesi culture. Collectively, our results indicate that platelets directly contribute to innate control of Plasmodium infection in human malaria.
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Affiliation(s)
- Steven Kho
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Bridget E Barber
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Edison Johar
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Benediktus Andries
- Timika Malaria Research Programme, Papuan Health and Community Development Foundation, Timika, Papua, Indonesia
| | - Jeanne R Poespoprodjo
- Timika Malaria Research Programme, Papuan Health and Community Development Foundation, Timika, Papua, Indonesia
- Rumah Sakit Umum Daerah Kabupaten Mimika, Timika, Papua, Indonesia
- Department of Paediatrics, University of Gadjah Mada, Yogyakarta, Indonesia
| | - Enny Kenangalem
- Timika Malaria Research Programme, Papuan Health and Community Development Foundation, Timika, Papua, Indonesia
- Rumah Sakit Umum Daerah Kabupaten Mimika, Timika, Papua, Indonesia
| | - Kim A Piera
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Anna Ehmann
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Ric N Price
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom
| | - Timothy William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
- Jesselton Medical Centre, Kota Kinabalu, Sabah, Malaysia; and
- Clinical Research Centre, Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Ministry of Health, Malaysia
| | - Tonia Woodberry
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Simon Foote
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
| | - Gabriela Minigo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
| | - Tsin W Yeo
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Matthew J Grigg
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Nicholas M Anstey
- Global and Tropical Health Division, Menzies School of Health Research and Charles Darwin University, Darwin, NT, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Kota Kinabalu, Sabah, Malaysia
| | - Brendan J McMorran
- Department of Immunology and Infectious Disease, The John Curtin School of Medical Research, Australian National University, Canberra, ACT, Australia
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Affiliation(s)
- Brendan J. McMorran
- Department of Immunology and Infectious Disease; John Curtin School of Medical Research; Australian National University; Canberra Australia
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18
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Mkumbaye SI, Minja DTR, Jespersen JS, Alifrangis M, Kavishe RA, Mwakalinga SB, Lusingu JP, Theander TG, Lavstsen T, Wang CW. Cellulose filtration of blood from malaria patients for improving ex vivo growth of Plasmodium falciparum parasites. Malar J 2017; 16:69. [PMID: 28183301 PMCID: PMC5301330 DOI: 10.1186/s12936-017-1714-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 01/26/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Establishing in vitro Plasmodium falciparum culture lines from patient parasite isolates can offer deeper understanding of geographic variations of drug sensitivity and mechanisms of malaria pathogenesis and immunity. Cellulose column filtration of blood is an inexpensive, rapid and effective method for the removal of host factors, such as leucocytes and platelets, significantly improving the purification of parasite DNA in a blood sample. METHODS In this study, the effect of cellulose column filtration of venous blood on the initial in vitro growth of P. falciparum parasite isolates from Tanzanian children admitted to hospital was tested. The parasites were allowed to expand in culture without subcultivation until 5 days after admission or the appearance of dead parasites and parasitaemia was determined daily. To investigate whether the filtration had an effect on clonality, P. falciparum merozoite surface protein 2 genotyping was performed using nested PCR on extracted genomic DNA, and the var gene transcript levels were investigated, using quantitative PCR on extracted RNA, at admission and 4 days of culture. RESULTS The cellulose-filtered parasites grew to higher parasitaemia faster than non-filtered parasites seemingly due to a higher development ratio of ring stage parasites progressing into the late stages. Cellulose filtration had no apparent effect on clonality or var gene expression; however, evident differences were observed after only 4 days of culture in both the number of clones and transcript levels of var genes compared to the time of admission. CONCLUSIONS Cellulose column filtration of parasitized blood is a cheap, applicable method for improving cultivation of P. falciparum field isolates for ex vivo based assays; however, when assessing phenotype and genotype of cultured parasites, in general, assumed to represent the in vivo infection, caution is advised.
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Affiliation(s)
- Sixbert I Mkumbaye
- Kilimanjaro Clinical Research Institute, Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Daniel T R Minja
- Korogwe Research Station, Tanga Centre, National Institute for Medical Research, Tanga, Tanzania
| | - Jakob S Jespersen
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Centre for Medical Parasitology, University of Copenhagen, CSS Building 22-23, Øster Farimagsgade 5, PO Box 2099, 1014, Copenhagen K, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | - Michael Alifrangis
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Centre for Medical Parasitology, University of Copenhagen, CSS Building 22-23, Øster Farimagsgade 5, PO Box 2099, 1014, Copenhagen K, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | - Reginald A Kavishe
- Kilimanjaro Clinical Research Institute, Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Steven B Mwakalinga
- Kilimanjaro Clinical Research Institute, Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - John P Lusingu
- Korogwe Research Station, Tanga Centre, National Institute for Medical Research, Tanga, Tanzania
| | - Thor G Theander
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Centre for Medical Parasitology, University of Copenhagen, CSS Building 22-23, Øster Farimagsgade 5, PO Box 2099, 1014, Copenhagen K, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | - Thomas Lavstsen
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Centre for Medical Parasitology, University of Copenhagen, CSS Building 22-23, Øster Farimagsgade 5, PO Box 2099, 1014, Copenhagen K, Denmark.,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark
| | - Christian W Wang
- Department of Immunology and Microbiology, Faculty of Health and Medical Sciences, Centre for Medical Parasitology, University of Copenhagen, CSS Building 22-23, Øster Farimagsgade 5, PO Box 2099, 1014, Copenhagen K, Denmark. .,Department of Infectious Diseases, Rigshospitalet, Copenhagen, Denmark.
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Platelets activate a pathogenic response to blood-stage Plasmodium infection but not a protective immune response. Blood 2017; 129:1669-1679. [PMID: 28096086 DOI: 10.1182/blood-2016-08-733519] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 12/28/2016] [Indexed: 01/30/2023] Open
Abstract
Clinical studies indicate that thrombocytopenia correlates with the development of severe falciparum malaria, suggesting that platelets either contribute to control of parasite replication, possibly as innate parasite killer cells or function in eliciting pathogenesis. Removal of platelets by anti-CD41 mAb treatment, platelet inhibition by aspirin, and adoptive transfer of wild-type (WT) platelets to CD40-KO mice, which do not control parasite replication, resulted in similar parasitemia compared with control mice. Human platelets at a physiologic ratio of 1 platelet to 9 red blood cells (RBCs) did not inhibit the in vitro development or replication of blood-stage Plasmodium falciparum The percentage of Plasmodium-infected (iRBCs) with bound platelets during the ascending parasitemia in Plasmodium chabaudi- and Plasmodium berghei-infected mice and the 48-hour in vitro cycle of P falciparum was <10%. P chabaudi and P berghei iRBCs with apoptotic parasites (TdT+) exhibited minimal platelet binding (<5%), which was similar to nonapoptotic iRBCs. These findings collectively indicate platelets do not kill bloodstage Plasmodium at physiologically relevant effector-to-target ratios. P chabaudi primary and secondary parasitemia was similar in mice depleted of platelets by mAb-injection just before infection, indicating that activation of the protective immune response does not require platelets. In contrast to the lack of an effect on parasite replication, adoptive transfer of WT platelets to CD40-KO mice, which are resistant to experimental cerebral malaria, partially restored experimental cerebral malaria mortality and symptoms in CD40-KO recipients, indicating platelets elicit pathogenesis and platelet CD40 is a key molecule.
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20
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Middleton E, Rondina MT. Platelets in infectious disease. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2016; 2016:256-261. [PMID: 27913489 PMCID: PMC6142503 DOI: 10.1182/asheducation-2016.1.256] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Sepsis is a dynamic, acute, infectious disease syndrome characterized by dysregulated thrombo-inflammatory responses. The high mortality associated with sepsis has been recognized since the earliest clinicians' writings. Despite this, advances in the treatment of sepsis have been more modest. This is limited, in part, by the heterogeneity in the definition, population, presentation, and causal factors of infectious syndromes. Given the persistently high morbidity and mortality associated with sepsis, a better understanding of the dysregulated cellular biology underpinning sepsis is needed. Platelets are small, anucleate cells that have hemostatic, inflammatory, and immune-mediating properties. Platelets are the second most common circulating blood cell, and emerging evidence suggests that platelets serve as sentinel and effector cells during infectious syndromes. Nevertheless, the molecular and functional changes that occur in platelets during sepsis, and their impact on the clinical course of infected patients, remain incompletely understood. In this review, we first highlight the complex and dynamic pathophysiology characteristics of acute, systemic infections and we then discuss established and emerging evidence of the roles of platelets in sepsis.
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Affiliation(s)
- Elizabeth Middleton
- Program in Molecular Medicine and
- Department Internal Medicine, University of Utah, Salt Lake City, UT; and
| | - Matthew T. Rondina
- Program in Molecular Medicine and
- Department Internal Medicine, University of Utah, Salt Lake City, UT; and
- Department of Internal Medicine at the George E. Wahlen Salt Lake City VAMC, Salt Lake City, UT
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21
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Middleton EA, Weyrich AS, Zimmerman GA. Platelets in Pulmonary Immune Responses and Inflammatory Lung Diseases. Physiol Rev 2016; 96:1211-59. [PMID: 27489307 PMCID: PMC6345245 DOI: 10.1152/physrev.00038.2015] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Platelets are essential for physiological hemostasis and are central in pathological thrombosis. These are their traditional and best known activities in health and disease. In addition, however, platelets have specializations that broaden their functional repertoire considerably. These functional capabilities, some of which are recently discovered, include the ability to sense and respond to infectious and immune signals and to act as inflammatory effector cells. Human platelets and platelets from mice and other experimental animals can link the innate and adaptive limbs of the immune system and act across the immune continuum, often also linking immune and hemostatic functions. Traditional and newly recognized facets of the biology of platelets are relevant to defensive, physiological immune responses of the lungs and to inflammatory lung diseases. The emerging view of platelets as blood cells that are much more diverse and versatile than previously thought further predicts that additional features of the biology of platelets and of megakaryocytes, the precursors of platelets, will be discovered and that some of these will also influence pulmonary immune defenses and inflammatory injury.
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Affiliation(s)
- Elizabeth A Middleton
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, and the Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah
| | - Andrew S Weyrich
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, and the Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah
| | - Guy A Zimmerman
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, and the Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah
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22
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Wassmer SC, Grau GER. Platelets as pathogenetic effectors and killer cells in cerebral malaria. Expert Rev Hematol 2016; 9:515-7. [DOI: 10.1080/17474086.2016.1179571] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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23
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Rondina MT, Garraud O. Emerging evidence for platelets as immune and inflammatory effector cells. Front Immunol 2014; 5:653. [PMID: 25566264 PMCID: PMC4270189 DOI: 10.3389/fimmu.2014.00653] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 12/06/2014] [Indexed: 12/20/2022] Open
Abstract
While traditionally recognized for their roles in hemostatic pathways, emerging evidence demonstrates that platelets have previously unrecognized, dynamic roles that span the immune continuum. These newly recognized platelet functions, including the secretion of immune mediators, interactions with endothelial cells, monocytes, and neutrophils, toll-like receptor (TLR) mediated responses, and induction of neutrophil extracellular trap formation, bridge thrombotic and inflammatory pathways and contribute to host defense mechanisms against invading pathogens. In this focused review, we highlight several of these emerging aspects of platelet biology and their implications in clinical infectious syndromes.
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Affiliation(s)
- Matthew T Rondina
- Division of General Internal Medicine, University of Utah , Salt Lake City, UT , USA ; Program in Molecular Medicine, University of Utah School of Medicine , Salt Lake City, UT , USA ; Department of Internal Medicine, George E. Wahlen Department of Veterans Affairs Medical Center , Salt Lake City, UT , USA
| | - Olivier Garraud
- Faculty of Medicine of Saint-Etienne, University of Lyon , Lyon , France ; French Blood Establishment, Auvergne-Loire , Saint-Etienne , France
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24
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McMorran BJ, Burgio G, Foote SJ. New insights into the protective power of platelets in malaria infection. Commun Integr Biol 2013; 6:e23653. [PMID: 23710276 PMCID: PMC3656011 DOI: 10.4161/cib.23653] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2013] [Accepted: 01/17/2013] [Indexed: 12/18/2022] Open
Abstract
Platelets, as well as regulating blood hemostasis, are an important component of the body’s defense against invading microbial pathogens. We previously reported that platelets protect during malaria infection by binding Plasmodium-infected erythrocytes (IE) and killing the parasite within. More recent studies have now revealed the platelet plasmocidal factor, platelet factor 4 (PF4) and the red cell-expressed Duffy-antigen molecule as the central players in the parasite killing activity of platelets.
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Affiliation(s)
- Brendan J McMorran
- Australian School of Advanced Medicine; Macquarie University; Macquarie Park, NSW Australia
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25
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A method for positive and negative selection of Plasmodium falciparum platelet-mediated clumping parasites and investigation of the role of CD36. PLoS One 2013; 8:e55453. [PMID: 23405153 PMCID: PMC3566186 DOI: 10.1371/journal.pone.0055453] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 12/29/2012] [Indexed: 01/08/2023] Open
Abstract
Platelet-mediated clumping of Plasmodium falciparum infected erythrocytes (IEs) is a frequently observed parasite adhesion phenotype. The importance of clumping in severe malaria and the molecular mechanisms behind this phenomenon are incompletely understood. Three platelet surface molecules have previously been identified as clumping receptors: CD36, globular C1q receptor (gC1qR/HABP1/p32), and P-selectin (CD62P), but the parasite ligands mediating this phenotype are unknown. The aim of this work was to develop a selection method to facilitate investigations of the molecular mechanisms of clumping in selected P. falciparum lines. Magnetic beads coated with anti-platelet antibodies were used to positively and negatively select clumping IEs from P. falciparum strains IT, HB3, 3D7 and Dd2. Clumping in all four positively selected parasite lines was abolished by antibodies to CD36, but was not affected by antibodies to gC1qR or P-selectin. Clumping positive lines showed significantly higher binding to CD36 than clumping negative lines in flow adhesion assays (strains IT, HB3 and 3D7, p<0.05 for all strains, paired t test) and static assays (strain Dd2, p<0.0001 paired t test). However, clumping negative lines IT, HB3 and 3D7 did show some binding to CD36 under flow conditions, indicating that CD36-binding is not sufficient for clumping. These data show that CD36-dependent clumping positive and negative lines can easily be selected from P. falciparum laboratory strains. CD36-binding is necessary but not sufficient for clumping, and the molecular differences between clumping positive and negative parasite lines responsible for the phenotype require further investigation.
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27
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McMorran BJ, Wieczorski L, Drysdale KE, Chan JA, Huang HM, Smith C, Mitiku C, Beeson JG, Burgio G, Foote SJ. Platelet factor 4 and Duffy antigen required for platelet killing of Plasmodium falciparum. Science 2012; 338:1348-51. [PMID: 23224555 DOI: 10.1126/science.1228892] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Platelets restrict the growth of intraerythrocytic malaria parasites by binding to parasitized cells and killing the parasite within. Here, we show that the platelet molecule platelet factor 4 (PF4 or CXCL4) and the erythrocyte Duffy-antigen receptor (Fy) are necessary for platelet-mediated killing of Plasmodium falciparum parasites. PF4 is released by platelets on contact with parasitized red cells, and the protein directly kills intraerythrocytic parasites. This function for PF4 is critically dependent on Fy, which binds PF4. Genetic disruption of Fy expression inhibits binding of PF4 to parasitized cells and concomitantly prevents parasite killing by both human platelets and recombinant human PF4. The protective function afforded by platelets during a malarial infection may therefore be compromised in Duffy-negative individuals, who do not express Fy.
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Affiliation(s)
- Brendan J McMorran
- Australian School of Advanced Medicine, Macquarie University, Sydney, NSW 2109, Australia.
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28
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Vieira-de-Abreu A, Campbell RA, Weyrich AS, Zimmerman GA. Platelets: versatile effector cells in hemostasis, inflammation, and the immune continuum. Semin Immunopathol 2011; 34:5-30. [PMID: 21818701 DOI: 10.1007/s00281-011-0286-4] [Citation(s) in RCA: 217] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 07/20/2011] [Indexed: 12/28/2022]
Abstract
Platelets are chief effector cells in hemostasis. In addition, however, their specializations include activities and intercellular interactions that make them key effectors in inflammation and in the continuum of innate and adaptive immunity. This review focuses on the immune features of human platelets and platelets from experimental animals and on interactions between inflammatory, immune, and hemostatic activities of these anucleate but complex and versatile cells. The experimental findings and evidence for physiologic immune functions include previously unrecognized biologic characteristics of platelets and are paralleled by new evidence for unique roles of platelets in inflammatory, immune, and thrombotic diseases.
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Affiliation(s)
- Adriana Vieira-de-Abreu
- Department of Medicine, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
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29
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Sriprawat K, Kaewpongsri S, Suwanarusk R, Leimanis ML, Lek-Uthai U, Phyo AP, Snounou G, Russell B, Renia L, Nosten F. Effective and cheap removal of leukocytes and platelets from Plasmodium vivax infected blood. Malar J 2009; 8:115. [PMID: 19490618 PMCID: PMC2694833 DOI: 10.1186/1475-2875-8-115] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Accepted: 06/02/2009] [Indexed: 11/19/2022] Open
Abstract
Background Investigations of Plasmodium vivax are restricted to samples collected from infected persons or primates, because this parasite cannot be maintained in in vitro cultures. Contamination of P. vivax isolates with host leukocytes and platelets is detrimental to a range of ex vivo and molecular investigations. Easy-to-produce CF11 cellulose filters have recently provided us with an inexpensive method for the removal of leukocytes and platelets. This contrasted with previous reports of unacceptably high levels of infected red blood cell (IRBC) retention by CF11. The aims of this study were to compare the ability of CF11 cellulose filters and the commercial filter Plasmodipur at removing leukocyte and platelet, and to investigate the retention of P. vivax IRBCs by CF11 cellulose filtration. Methods and Results Side-by-side comparison of six leukocyte removal methods using blood samples from five healthy donor showed that CF11 filtration reduced the mean initial leukocyte counts from 9.4 × 103 per μl [95%CI 5.2–13.5] to 0.01 × 103 [95%CI 0.01–0.03]. The CF11 was particularly effective at removing neutrophils. CF11 treatment also reduced initial platelet counts from 211.6 × 103 per μl [95%CI 107.5–315.7] to 0.8 × 103 per μl [95%CI -0.7–2.2]. Analysis of 30 P. vivax blood samples before and after CF11 filtration showed only a minor loss in parasitaemia (≤ 7.1% of initial counts). Stage specific retention of P. vivax IRBCs was not observed. Conclusion CF11 filtration is the most cost and time efficient method for the production of leukocyte- and platelet-free P. vivax-infected erythrocytes from field isolates.
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30
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McMorran BJ, Marshall VM, de Graaf C, Drysdale KE, Shabbar M, Smyth GK, Corbin JE, Alexander WS, Foote SJ. Platelets kill intraerythrocytic malarial parasites and mediate survival to infection. Science 2009; 323:797-800. [PMID: 19197068 DOI: 10.1126/science.1166296] [Citation(s) in RCA: 198] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Platelets play a critical role in the pathogenesis of malarial infections by encouraging the sequestration of infected red blood cells within the cerebral vasculature. But platelets also have well-established roles in innate protection against microbial infections. We found that purified human platelets killed Plasmodium falciparum parasites cultured in red blood cells. Inhibition of platelet function by aspirin and other platelet inhibitors abrogated the lethal effect human platelets exert on P. falciparum parasites. Likewise, platelet-deficient and aspirin-treated mice were more susceptible to death during erythrocytic infection with Plasmodium chabaudi. Both mouse and human platelets bind malarial-infected red cells and kill the parasite within. These results indicate a protective function for platelets in the early stages of erythrocytic infection distinct from their role in cerebral malaria.
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Affiliation(s)
- Brendan J McMorran
- Menzies Research Institute, University of Tasmania, Private Bag 23, Hobart, Tasmania 7000, Australia.
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31
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Antimicrobial Host Defense. Platelets 2007. [DOI: 10.1016/b978-012369367-9/50802-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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32
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Alugupalli KR, Michelson AD, Joris I, Schwan TG, Hodivala-Dilke K, Hynes RO, Leong JM. Spirochete-platelet attachment and thrombocytopenia in murine relapsing fever borreliosis. Blood 2003; 102:2843-50. [PMID: 12855586 DOI: 10.1182/blood-2003-02-0426] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thrombocytopenia is common in persons infected with relapsing fever Borreliae. We previously showed that the relapsing fever spirochete Borrelia hermsii binds to and activates human platelets in vitro and that, after platelet activation, high-level spirochete-platelet attachment is mediated by integrin alpha IIb beta 3, a receptor that requires platelet activation for full function. Here we established that B hermsii infection of the mouse results in severe thrombocytopenia and a functional defect in hemostasis caused by accelerated platelet loss. Disseminated intravascular coagulation, immune thrombocytopenic purpura, or splenic sequestration did not play a discernible role in this model. Instead, spirochete-platelet complexes were detected in the blood of infected mice, suggesting that platelet attachment by bacteria might result in platelet clearance. Consistent with this, splenomegaly and thrombocytopenia temporally correlated with spirochetemia, and the severity of thrombocytopenia directly correlated with the degree of spirochetemia. Activation of platelets and integrin alpha IIb beta 3 were apparently not required for bacterium-platelet binding or platelet clearance because the bacterium-bound platelets in the circulation were not activated, and platelet binding and thrombocytopenia during infection of beta 3-deficient and wild-type mice were indistinguishable. These findings suggest that thrombocytopenia of relapsing fever is the result of platelet clearance after beta 3-independent bacterial attachment to circulating platelets.
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Affiliation(s)
- Kishore R Alugupalli
- Department of Molecular Genetics and Microbiology, University of Massachusetts Medical School, 55 Lake Ave N, Worcester, MA 01655, USA
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33
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Robert R, Nail S, Marot-Leblond A, Cottin J, Miegeville M, Quenouillere S, Mahaza C, Senet JM. Adherence of platelets to Candida species in vivo. Infect Immun 2000; 68:570-6. [PMID: 10639419 PMCID: PMC97178 DOI: 10.1128/iai.68.2.570-576.2000] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The in vivo interactions of platelets with Candida species yeast cells were investigated in a murine model. Mice were injected intravenously via the lateral caudal vein, and blood drawn by periorbital puncture was collected in phosphate-buffered saline-formaldehyde to avoid in vitro platelet activation. The study of the clearance of blastoconidia of Candida albicans and Candida glabrata showed that these cells disappeared quickly from the bloodstream. Microscopic observation of blood samples, stained by Calcofluor white or May Grunwald Giemsa, demonstrated the rapid attachment of platelets to fungal elements of all the Candida spp. tested. The attachment of murine platelets to C. albicans cells, observed by scanning electron microscopy, revealed morphological changes. The platelets lost their discoid shape, generated pseudopodia, and flattened against the yeast cells. The reversibility of platelet binding to C. albicans by chelating agents suggests a cation-dependent link. In contrast, the fixation of C. glabrata and Candida tropicalis was not modified by chelating agents. The mechanisms involved in the in vivo adherence of platelets to Candida cells may therefore differ according to the species of Candida.
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Affiliation(s)
- R Robert
- Groupe d'Etude des Interactions Hôte-Parasite, Laboratoire de Parasitologie-Mycologie, Faculté de Pharmacie, 49000 Angers, France.
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34
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Christin L, Wysong DR, Meshulam T, Hastey R, Simons ER, Diamond RD. Human platelets damage Aspergillus fumigatus hyphae and may supplement killing by neutrophils. Infect Immun 1998; 66:1181-9. [PMID: 9488412 PMCID: PMC108032 DOI: 10.1128/iai.66.3.1181-1189.1998] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Neutropenia is considered a significant risk factor for invasive aspergillosis but is almost always associated with concurrent thrombocytopenia. Studies determined that platelets, like neutrophils, attached to cell walls of the invasive hyphal form of Aspergillus fumigatus. Organisms were damaged as shown by loss of cell wall integrity in scanning laser confocal microscopy and release of defined hyphal surface glycoproteins. Rapid expression appearance of surface antigen CD63 and release of markers of platelet degranulation confirmed activation during attachment to hyphae. Optimal platelet activation required opsonization of hyphae with fresh or heat-inactivated whole plasma. These effects of opsonization with whole plasma could not be duplicated by pooled human serum, immunoglobulin G, or fibrinogen, whether used separately or combined. Thus, platelets in the presence of whole plasma have the potential to play an important role in normal host defenses against invasive aspergillosis.
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Affiliation(s)
- L Christin
- Department of Medicine, Boston Medical Center, and Boston University School of Medicine, Massachusetts 02118, USA
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35
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Chumpitazi BF, Simon J, Polack B, Peyron F, Picot S, Ricard J, Ambroise-Thomas P. Human platelet inhibition of Toxoplasma gondii growth. Clin Exp Immunol 1998; 111:325-33. [PMID: 9486399 PMCID: PMC1904904 DOI: 10.1046/j.1365-2249.1998.00499.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The human platelet contribution against the intracellular growth of the parasite in vitro in human pulmonary fibroblasts was explored. It was observed that tachyzoites of Toxoplasma gondii induced activation of human platelets and additionally that platelets mediated inhibition of intracellular growth in a virulent T. gondii strain. A prominent role for platelet-derived growth factor (PDGF) was demonstrated in this phenomenon, by testing human recombinant PDGF-AA, -AB and -BB and antibodies to human PDGF-AB that partially reversed its effects. Moreover, the effect of PDGF was significantly higher if the host cells were treated 2 h before parasite infection. PDGF was not directly 'toxic' to free tachyzoites, but only affected parasites within host cells. PDGF-mediated inhibition may involve the cyclooxygenase cycle of the fibroblasts being partially reversed by the cyclooxygenase inhibitors, acetylsalicylic acid and indomethacin. However, a thromboxane synthetase pathway was not implicated. PDGF action against intracellular tachyzoites may also include increased IL-6 production in fibroblasts. Finally, transforming growth factor-beta 1 (TGF-beta1), another component of alpha-granules released at the same time as PDGF, may not be antagonistic to the PDGF parasite inhibitory effect in confluent host cells.
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Affiliation(s)
- B F Chumpitazi
- Département de Parasitologie-Mycologie Médicale et Moléculaire, RHAP, CNRS UPRES A 5082, Université Joseph Fourier-Grenoble I, La Tronche, France
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36
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Abstract
Various molecules expressed on the surface of platelets have been shown to mediate the protective or deleterious role of these cells in immuno-inflammatory mechanisms. Increasing evidence points to the involvement of the cell adhesion molecules, gpIIb-IIIa, P-selectin, CD31, LFA-1, and CD36 in the interaction between platelets and endothelial cells as well as other cell types. The possible role of these molecules in the ability of platelets to support endothelium and to protect against tumour necrosis factor mediated cytolysis or parasitic invasion are reviewed. The involvement of platelets as effectors of tissue damage in cerebral malaria, lipopolysaccharide induced pathology, and pulmonary fibrosis is also discussed. This has then been extended to include the intercellular mechanisms underpinning their pathogenic role in metastasis, transplant rejection, stroke, brain hypoxia, and related conditions. A better understanding of the complex regulation and hierarchical organisation of these various platelet adhesion molecules may prove useful in the development of new approaches to the treatment of such diseases.
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Affiliation(s)
- D N Männel
- Department of Pathology, University of Regensburg, Germany
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37
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Robert R, Mahaza C, Miegeville M, Ponton J, Marot-Leblond A, Senet JM. Binding of resting platelets to Candida albicans germ tubes. Infect Immun 1996; 64:3752-7. [PMID: 8751925 PMCID: PMC174289 DOI: 10.1128/iai.64.9.3752-3757.1996] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
The binding of resting platelets to Candida albicans germ tubes was studied by means of an affinity column in which germ tubes were physically immobilized. Adhesion of platelets to the column was dependent on both the germ tube concentration and the number of platelets applied. It was found that the interaction of C. albicans germ tubes with platelets is specific and should be mediated by a fungal protein receptor. The results obtained by scanning electron microscopy confirmed that resting platelets can fix directly onto germ tubes. In addition, this study showed that attachment of platelets onto C. albicans is associated with morphological changes. Platelets lost their discoid shape, became globular, generated spikes or pseudopods, and then flattened on the yeast cells.
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Affiliation(s)
- R Robert
- Laboratoire d'Immunologie-Mycologie-Bactériologie, UFR des Sciences Médicales et Pharmaceutiques, Angers, France
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38
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el-Shoura S. Falciparum malaria in naturally infected humans. III. Platelet ultrastructural alterations during thrombocytopenia. VIRCHOWS ARCHIV. B, CELL PATHOLOGY INCLUDING MOLECULAR PATHOLOGY 1993; 63:257-62. [PMID: 8099463 DOI: 10.1007/bf02899270] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Platelet ultrastructural alterations are described in thrombocytopenic Saudi patients with acute falciparum malaria (AFM) and compared with the appearances of platelets from same patients after successful antimalarial treatment. Some altered platelets lost their discoid form and showed concentration of organelles in the cell centers. Other platelets were devoid of the alpha- and dense granules usually seen in normal cells. The lack of these granules is known to be associated with bleeding symptoms. The bundle of microtubules known to maintain the discoid form of platelets, and the contractile fibrillar elements responsible for "platelet propulsive movement" were either dispersed or absent. The open canalicular system known to be the main endocytic and secretory pathway was either absent, or distended and obstructed by cytoplasmic extensions. Most of platelets developed surface pseudopodia and endocytic vacuoles that are characteristic features of phagocytic cells. Different mechanisms have been suggested as the cause of these alterations. This study indicates that AFM is associated with platelet structural alterations which could be an important cause of thrombocytopenia; the frequency of these alterations correlated with the degree of parasitaemia. Older patients presented with less marked parasitaemia than younger patients, possibly due to the less mature immune system in the latter. It is also possible that AFM may have independent effects on the structure of human platelets.
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Affiliation(s)
- S el-Shoura
- Department of Pathology, College of Medicine, King Saud University, Kingdom of Saudi Arabia
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Grau GE, Modlin RL. Immune mechanisms in bacterial and parasitic diseases: protective immunity versus pathology. Curr Opin Immunol 1991; 3:480-5. [PMID: 1684508 DOI: 10.1016/0952-7915(91)90007-n] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The immunological mechanisms that contribute to resistance versus susceptibility to bacterial and parasitic infection are central to the development of improved prophylactic and therapeutic strategies. The delineation of two subsets of CD4+ T cells in the mouse that regulate these responses has provided a tremendous advance in understanding disease pathogenesis. The elucidation of protective immune mechanisms distinct from those that cause tissue damage should lead to the development of appropriate vaccines against these devastating illnesses.
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Affiliation(s)
- G E Grau
- University of Geneva, Switzerland
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40
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Auriault C, Damonneville M, Pancré V, Capron A. Effector functions of platelets in parasitic diseases and their regulation by cytokines. Diagn Microbiol Infect Dis 1990; 13:423-7. [PMID: 2126501 DOI: 10.1016/0732-8893(90)90013-l] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- C Auriault
- Institut Pasteur, Centre de Biologie et d'Immunologie Parasitaire, Lille, France
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41
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Polack B, Peyron F, Kolodié L, Ambroise-Thomas P, Santoro F. Platelet receptors involved in Plasmodium falciparum growth inhibition. Thromb Res 1990; 59:663-7. [PMID: 1700490 DOI: 10.1016/0049-3848(90)90425-c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- B Polack
- Laboratoire d'Hématologie, CNRS URA 1344, Faculté de Médecine de Grenoble, La Tronche, France
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