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Grabowska J, Léopold V, Olesek K, Nijen Twilhaar MK, Affandi AJ, Brouwer MC, Jongerius I, Verschoor A, van Kooten C, van Kooyk Y, Storm G, van ‘t Veer C, den Haan JMM. Platelets interact with CD169 + macrophages and cDC1 and enhance liposome-induced CD8 + T cell responses. Front Immunol 2023; 14:1290272. [PMID: 38054006 PMCID: PMC10694434 DOI: 10.3389/fimmu.2023.1290272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 11/03/2023] [Indexed: 12/07/2023] Open
Abstract
Historically platelets are mostly known for their crucial contribution to hemostasis, but there is growing understanding of their role in inflammation and immunity. The immunomodulatory role of platelets entails interaction with pathogens, but also with immune cells including macrophages and dendritic cells (DCs), to activate adaptive immune responses. In our previous work, we have demonstrated that splenic CD169+ macrophages scavenge liposomes and collaborate with conventional type 1 DCs (cDC1) to induce expansion of CD8+ T cells. Here, we show that platelets associate with liposomes and bind to DNGR-1/Clec9a and CD169/Siglec-1 receptors in vitro. In addition, platelets interacted with splenic CD169+ macrophages and cDC1 and further increased liposome internalization by cDC1. Most importantly, platelet depletion prior to liposomal immunization resulted in significantly diminished antigen-specific CD8+ T cell responses, but not germinal center B cell responses. Previously, complement C3 was shown to be essential for platelet-mediated CD8+ T cell activation during bacterial infection. However, after liposomal vaccination CD8+ T cell priming was not dependent on complement C3. While DCs from platelet-deficient mice exhibited unaltered maturation status, they did express lower levels of CCR7. In addition, in the absence of platelets, CCL5 plasma levels were significantly reduced. Overall, our findings demonstrate that platelets engage in a cross-talk with CD169+ macrophages and cDC1 and emphasize the importance of platelets in induction of CD8+ T cell responses in the context of liposomal vaccination.
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Affiliation(s)
- Joanna Grabowska
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Biology and Immunology Program, Cancer Center Amsterdam, Amsterdam, Netherlands
- Cancer Immunology Program, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Valentine Léopold
- Center of Experimental and Molecular Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Department of Anesthesiology and Critical Care, Paris University, Lariboisière Hospital, Paris, France
- Inserm UMR-S 942, Cardiovascular Markers in Stress Conditions (MASCOT), University of Paris, Paris, France
| | - Katarzyna Olesek
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Biology and Immunology Program, Cancer Center Amsterdam, Amsterdam, Netherlands
- Cancer Immunology Program, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Maarten K. Nijen Twilhaar
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Biology and Immunology Program, Cancer Center Amsterdam, Amsterdam, Netherlands
- Cancer Immunology Program, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Alsya J. Affandi
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Biology and Immunology Program, Cancer Center Amsterdam, Amsterdam, Netherlands
- Cancer Immunology Program, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Mieke C. Brouwer
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Centre, Amsterdam Infection and Immunity Institute, Amsterdam, Netherlands
| | - Ilse Jongerius
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Amsterdam University Medical Centre, Amsterdam Infection and Immunity Institute, Amsterdam, Netherlands
| | - Admar Verschoor
- Department of Dermatology, University of Lübeck, Lübeck, Germany
- Department of Otorhinolaryngology, Technische Universität München and Klinikum Rechts der Isar, Munich, Germany
| | - Cees van Kooten
- Department of Medicine, Division of Nephrology and Transplant Medicine, Leiden University Medical Center, Leiden, Netherlands
| | - Yvette van Kooyk
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Biology and Immunology Program, Cancer Center Amsterdam, Amsterdam, Netherlands
- Cancer Immunology Program, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
| | - Gert Storm
- Department of Pharmaceutics, Faculty of Science, Utrecht University, Utrecht, Netherlands
- Department of Biomaterials, Science and Technology, Faculty of Science and Technology, University of Twente, Enschede, Netherlands
- Department of Surgery, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Cornelis van ‘t Veer
- Center of Experimental and Molecular Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Joke M. M. den Haan
- Department of Molecular Cell Biology and Immunology, Amsterdam UMC location Vrije Universiteit Amsterdam, Amsterdam, Netherlands
- Cancer Biology and Immunology Program, Cancer Center Amsterdam, Amsterdam, Netherlands
- Cancer Immunology Program, Amsterdam Institute for Infection and Immunity, Amsterdam, Netherlands
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2
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Zhao J, Xu X, Gao Y, Yu Y, Li C. Crosstalk between Platelets and SARS-CoV-2: Implications in Thrombo-Inflammatory Complications in COVID-19. Int J Mol Sci 2023; 24:14133. [PMID: 37762435 PMCID: PMC10531760 DOI: 10.3390/ijms241814133] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 08/14/2023] [Accepted: 08/22/2023] [Indexed: 09/29/2023] Open
Abstract
The SARS-CoV-2 virus, causing the devastating COVID-19 pandemic, has been reported to affect platelets and cause increased thrombotic events, hinting at the possible bidirectional interactions between platelets and the virus. In this review, we discuss the potential mechanisms underlying the increased thrombotic events as well as altered platelet count and activity in COVID-19. Inspired by existing knowledge on platelet-pathogen interactions, we propose several potential antiviral strategies that platelets might undertake to combat SARS-CoV-2, including their abilities to internalize the virus, release bioactive molecules to interfere with viral infection, and modulate the functions of immune cells. Moreover, we discuss current and potential platelet-targeted therapeutic strategies in controlling COVID-19, including antiplatelet drugs, anticoagulants, and inflammation-targeting treatments. These strategies have shown promise in clinical settings to alleviate the severity of thrombo-inflammatory complications and reduce the mortality rate among COVID-19 patients. In conclusion, an in-depth understanding of platelet-SARS-CoV-2 interactions may uncover novel mechanisms underlying severe COVID-19 complications and could provide new therapeutic avenues for managing this disease.
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Affiliation(s)
| | | | | | - Yijing Yu
- School of Medicine, The Chinese University of Hong Kong, Shenzhen 518172, China; (J.Z.); (X.X.); (Y.G.)
| | - Conglei Li
- School of Medicine, The Chinese University of Hong Kong, Shenzhen 518172, China; (J.Z.); (X.X.); (Y.G.)
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3
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Takada YK, Shimoda M, Takada Y. CD40L Activates Platelet Integrin αIIbβ3 by Binding to the Allosteric Site (Site 2) in a KGD-Independent Manner and HIGM1 Mutations Are Clustered in the Integrin-Binding Sites of CD40L. Cells 2023; 12:1977. [PMID: 37566056 PMCID: PMC10416995 DOI: 10.3390/cells12151977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 07/20/2023] [Accepted: 07/25/2023] [Indexed: 08/12/2023] Open
Abstract
CD40L is expressed in activated T cells, and it plays a major role in immune response and is a major therapeutic target for inflammation. High IgM syndrome type 1 (HIGM1) is a congenital functional defect in CD40L/CD40 signaling due to defective CD40L. CD40L is also stored in platelet granules and transported to the surface upon platelet activation. Platelet integrin αIIbβ3 is known to bind to fibrinogen and activation of αIIbβ3 is a key event that triggers platelet aggregation. Also, the KGD motif is critical for αIIbβ3 binding and the interaction stabilizes thrombus. Previous studies showed that CD40L binds to and activates integrins αvβ3 and α5β1 and that HIGM1 mutations are clustered in the integrin-binding sites. However, the specifics of CD40L binding to αIIbβ3 were unclear. Here, we show that CD40L binds to αIIbβ3 in a KGD-independent manner using CD40L that lacks the KGD motif. Two HIGM1 mutants, S128E/E129G and L155P, reduced the binding of CD40L to the classical ligand-binding site (site 1) of αIIbβ3, indicating that αIIbβ3 binds to the outer surface of CD40L trimer. Also, CD40L bound to the allosteric site (site 2) of αIIbβ3 and allosterically activated αIIbβ3 without inside-out signaling. Two HIMG1 mutants, K143T and G144E, on the surface of trimeric CD40L suppressed CD40L-induced αIIbβ3 activation. These findings suggest that CD40L binds to αIIbβ3 in a manner different from that of αvβ3 and α5β1 and induces αIIbβ3 activation. HIGM1 mutations are clustered in αIIbβ3 binding sites in CD40L and are predicted to suppress thrombus formation and immune responses through αIIbβ3.
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Affiliation(s)
- Yoko K. Takada
- Department of Dermatology, School of Medicine, UC Davis, Sacramento, CA 95817, USA (M.S.)
| | - Michiko Shimoda
- Department of Dermatology, School of Medicine, UC Davis, Sacramento, CA 95817, USA (M.S.)
| | - Yoshikazu Takada
- Department of Dermatology, School of Medicine, UC Davis, Sacramento, CA 95817, USA (M.S.)
- Department of Biochemistry and Molecular Medicine, School of Medicine, UC Davis, Sacramento, CA 95817, USA
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4
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Yan C, Wu H, Fang X, He J, Zhu F. Platelet, a key regulator of innate and adaptive immunity. Front Med (Lausanne) 2023; 10:1074878. [PMID: 36968817 PMCID: PMC10038213 DOI: 10.3389/fmed.2023.1074878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Accepted: 02/14/2023] [Indexed: 03/12/2023] Open
Abstract
Platelets, anucleate blood components, represent the major cell type involved in the regulation of hemostasis and thrombosis. In addition to performing haemostatic roles, platelets can influence both innate and adaptive immune responses. In this review, we summarize the development of platelets and their functions in hemostasis. We also discuss the interactions between platelet products and innate or adaptive immune cells, including neutrophils, monocytes, macrophages, T cells, B cells and dendritic cells. Activated platelets and released molecules regulate the differentiation and function of these cells via platelet-derived receptors or secreting molecules. Platelets have dual effects on nearly all immune cells. Understanding the exact mechanisms underlying these effects will enable further application of platelet transfusion.
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Affiliation(s)
- Cheng Yan
- Department of Blood Transfusion, Nanjing Jiangning Hospital, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Haojie Wu
- Department of Laboratory Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xianchun Fang
- Department of Blood Transfusion, Nanjing Jiangning Hospital, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Junji He
- Department of Blood Transfusion, Nanjing Jiangning Hospital, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Feng Zhu
- Department of Blood Transfusion, Nanjing Jiangning Hospital, The Affiliated Jiangning Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
- *Correspondence: Feng Zhu,
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Chen S, Zhang L, Chen L, Huang Q, Wang Y, Liang Y. Comprehensive analysis of glycoprotein VI-mediated platelet activation signaling pathway for predicting pan-cancer survival and response to anti-PD-1 immunotherapy. Comput Struct Biotechnol J 2023; 21:2873-2883. [PMID: 37206616 PMCID: PMC10189353 DOI: 10.1016/j.csbj.2023.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 04/03/2023] [Accepted: 04/04/2023] [Indexed: 05/21/2023] Open
Abstract
Platelets play a vital role in cancer and immunity. However, few comprehensive studies have been conducted on the role of platelet-related signaling pathways in various cancers and their responses to immune checkpoint blockade (ICB) therapy. In the present study, we focused on the glycoprotein VI-mediated platelet activation (GMPA) signaling pathway and comprehensively evaluated its roles in 19 types of cancers listed in The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO). Cox regression and meta-analyses showed that for all 19 types of cancers, patients with high GMPA scores tended to have a good prognosis. Furthermore, the GMPA signature score could serve as an independent prognostic factor for patients with skin cutaneous melanoma (SKCM). The GMPA signature was linked to tumor immunity in all 19 types of cancers, and was correlated with SKCM tumor histology. Compared to other signature scores, the GMPA signature scores for on-treatment samples were more robust predictors of the response to anti-PD-1 blockade in metastatic melanoma. Moreover, the GMPA signature scores were significantly negatively correlated with EMMPRIN (CD147) and positively correlated with CD40LG expression at the transcriptomic level in most cancer patient samples from the TCGA cohort and on-treatment samples from anti-PD1 therapy cohorts. The results of this study provide an important theoretical basis for the use of GMPA signatures, as well as GPVI-EMMPRIN and GPVI-CD40LG pathways, to predict the responses of cancer patients to various types of ICB therapy.
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6
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Regulatory Effects of Curcumin on Platelets: An Update and Future Directions. Biomedicines 2022; 10:biomedicines10123180. [PMID: 36551934 PMCID: PMC9775400 DOI: 10.3390/biomedicines10123180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/13/2022] Open
Abstract
The rhizomatous plant turmeric, which is frequently used as a spice and coloring ingredient, yields curcumin, a bioactive compound. Curcumin inhibits platelet activation and aggregation and improves platelet count. Platelets dysfunction results in several disorders, including inflammation, atherothrombosis, and thromboembolism. Several studies have proved the beneficial role of curcumin on platelets and hence proved it is an important candidate for the treatment of the aforementioned diseases. Moreover, curcumin is also frequently employed as an anti-inflammatory agent in conventional medicine. In arthritic patients, it has been shown to reduce the generation of pro-inflammatory eicosanoids and to reduce edema, morning stiffness, and other symptoms. Curcumin taken orally also reduced rats' acute inflammation brought on by carrageenan. Curcumin has also been proven to prevent atherosclerosis and platelet aggregation, as well as to reduce angiogenesis in adipose tissue. In the cerebral microcirculation, curcumin significantly lowered platelet and leukocyte adhesion. It largely modulated the endothelium to reduce platelet adhesion. Additionally, P-selectin expression and mice survival after cecal ligation and puncture were improved by curcumin, which also altered platelet and leukocyte adhesion and blood-brain barrier dysfunction. Through regulating many processes involved in platelet aggregation, curcuminoids collectively demonstrated detectable antiplatelet activity. Curcuminoids may therefore be able to prevent disorders linked to platelet activation as possible therapeutic agents. This review article proposes to highlight and discuss the regulatory effects of curcumin on platelets.
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7
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Kerstholt M, van de Schoor FR, Oosting M, Moorlag SJCFM, Li Y, Jaeger M, van der Heijden WA, Tunjungputri RN, dos Santos JC, Kischkel B, Vrijmoeth HD, Baarsma ME, Kullberg BJ, Lupse M, Hovius JW, van den Wijngaard CC, Netea MG, de Mast Q, Joosten LAB. Identifying platelet-derived factors as amplifiers of B. burgdorferi-induced cytokine production. Clin Exp Immunol 2022; 210:53-67. [PMID: 36001729 PMCID: PMC9585555 DOI: 10.1093/cei/uxac073] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 07/07/2022] [Accepted: 08/11/2022] [Indexed: 01/25/2023] Open
Abstract
Previous studies have shown that monocytes can be 'trained' or tolerized by certain stimuli to respond stronger or weaker to a secondary stimulation. Rewiring of glucose metabolism was found to be important in inducing this phenotype. As we previously found that Borrelia burgdorferi (B. burgdorferi), the causative agent of Lyme borreliosis (LB), alters glucose metabolism in monocytes, we hypothesized that this may also induce long-term changes in innate immune responses. We found that exposure to B. burgdorferi decreased cytokine production in response to the TLR4-ligand lipopolysaccharide (LPS). In addition, B. burgdorferi exposure decreased baseline levels of glycolysis, as assessed by lactate production. Using GWAS analysis, we identified a gene, microfibril-associated protein 3-like (MFAP3L) as a factor influencing lactate production after B. burgdorferi exposure. Validation experiments proved that MFAP3L affects lactate- and cytokine production following B. burgdorferi stimulation. This is mediated by functions of MFAP3L, which includes activating ERK2 and through activation of platelet degranulation. Moreover, we showed that platelets and platelet-derived factors play important roles in B. burgdorferi-induced cytokine production. Certain platelet-derived factors, such chemokine C-X-C motif ligand 7 (CXCL7) and (C-C motif) ligand 5 (CCL5), were elevated in the circulation of LB patients in comparison to healthy individuals.
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Affiliation(s)
| | | | - Marije Oosting
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Simone J C F M Moorlag
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Yang Li
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands,Department of Computational Biology for Individualised Medicine, Centre for Individualised Infection Medicine (CiiM) and TWINCORE, Joint Ventures Between the Helmholtz-Centre for Infection Research (HZI) and the Hannover Medical School (MHH), Hannover, Germany
| | - Martin Jaeger
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Wouter A van der Heijden
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Rahajeng N Tunjungputri
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands,Center for Tropical and Infectious Diseases (CENTRID), Faculty of Medicine Diponegoro University, Dr. Kariadi Hospital, Semarang, Indonesia
| | - Jéssica C dos Santos
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Brenda Kischkel
- Department of Internal Medicine and Radboud Institute of Molecular Life Sciences (RIMLS), Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Hedwig D Vrijmoeth
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - M E Baarsma
- Amsterdam Institute of Infection and Immunology, Center for Experimental and Molecular Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Bart-Jan Kullberg
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Mihaela Lupse
- Department of Infectious Diseases, University of Medicine and Pharmacy ‘Iuliu Hatieganu’, Cluj-Napoca, Romania
| | - Joppe W Hovius
- Amsterdam Institute of Infection and Immunology, Center for Experimental and Molecular Medicine, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Cees C van den Wijngaard
- National Institute for Public Health and the Environment (RIVM), Center of Infectious Disease Control, Bilthoven, The Netherlands
| | - Mihai G Netea
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands,Department for Immunology and Metabolism, Life and Medical Sciences Institute (LIMES), University of Bonn, Germany
| | - Quirijn de Mast
- Department of Internal Medicine and Radboudumc Center for Infectious diseases (RCI), Radboud University Medical Center, Nijmegen, The Netherlands
| | - Leo A B Joosten
- Correspondence: Leo A.B. Joosten, Lab Experimentele geneeskunde, Radboudumc, Geert Grooteplein Zuid 10, 6525 GA, Nijmegen, The Netherlands. E-mail:
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8
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Scopelliti F, Cattani C, Dimartino V, Mirisola C, Cavani A. Platelet Derivatives and the Immunomodulation of Wound Healing. Int J Mol Sci 2022; 23:ijms23158370. [PMID: 35955503 PMCID: PMC9368989 DOI: 10.3390/ijms23158370] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/22/2022] [Accepted: 07/25/2022] [Indexed: 02/01/2023] Open
Abstract
Besides their primary role in hemostasis, platelets contain a plethora of immunomodulatory molecules that profoundly affect the entire process of wound repair. Therefore, platelet derivatives, such as platelet-rich plasma or platelet lysate, have been widely employed with promising results in the treatment of chronic wounds. Platelet derivatives provide growth factors, cytokines, and chemokines targeting resident and immigrated cells belonging to the innate and adaptive immune system. The recruitment and activation of neutrophils and macrophages is critical for pathogen clearance in the early phase of wound repair. The inflammatory response begins with the release of cytokines, such as TGF-β, aimed at damping excessive inflammation and promoting the regenerative phase of wound healing. Dysregulation of the immune system during the wound healing process leads to persistent inflammation and delayed healing, which ultimately result in chronic wound. In this review, we summarize the role of the different immune cells involved in wound healing, particularly emphasizing the function of platelet and platelet derivatives in orchestrating the immunological response.
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9
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Chaudhary PK, Kim S, Kim S. An Insight into Recent Advances on Platelet Function in Health and Disease. Int J Mol Sci 2022; 23:ijms23116022. [PMID: 35682700 PMCID: PMC9181192 DOI: 10.3390/ijms23116022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 05/22/2022] [Accepted: 05/24/2022] [Indexed: 12/04/2022] Open
Abstract
Platelets play a variety of roles in vascular biology and are best recognized as primary hemostasis and thrombosis mediators. Platelets have a large number of receptors and secretory molecules that are required for platelet functionality. Upon activation, platelets release multiple substances that have the ability to influence both physiological and pathophysiological processes including inflammation, tissue regeneration and repair, cancer progression, and spreading. The involvement of platelets in the progression and seriousness of a variety of disorders other than thrombosis is still being discovered, especially in the areas of inflammation and the immunological response. This review represents an integrated summary of recent advances on the function of platelets in pathophysiology that connects hemostasis, inflammation, and immunological response in health and disease and suggests that antiplatelet treatment might be used for more than only thrombosis.
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10
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Chen X, Xu Y, Chen Q, Zhang H, Zeng Y, Geng Y, Shen L, Li F, Chen L, Chen GQ, Huang C, Liu J. The phosphatase PTEN links platelets with immune regulatory functions of mouse T follicular helper cells. Nat Commun 2022; 13:2762. [PMID: 35589797 PMCID: PMC9120038 DOI: 10.1038/s41467-022-30444-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/30/2022] [Indexed: 01/10/2023] Open
Abstract
Beyond a function in hemostasis and thrombosis, platelets can regulate innate and adaptive immune responses. Hyperactive platelets are frequently associated with multiple human autoimmune diseases, yet their pathogenic functions in these diseases have not been fully established. Emerging studies show an essential function of the phosphatase and tensin homolog (PTEN) in maintenance of immune homeostasis. Here, we show that mice with platelet-specific deletion of Pten, develop age-related lymphoproliferative diseases and humoral autoimmunity not seen in wildtype animals. Platelet-specific Pten-deficient mice have aberrant T cell activation, excessive T follicular helper (Tfh) cell responses and accumulation of platelet aggregates in lymph nodes. Transferred Pten-deficient platelets are able to infiltrate into the peripheral lymphoid tissues and form more aggregates. Moreover, Pten-deficient platelets are hyperactive and overproduce multiple Tfh-promoting cytokines via activation of the PDK1/mTORC2-AKT-SNAP23 pathway. Pten-deficient platelets show enhanced interaction with CD4+ T cells and promote conversion of CD4+ T cells into Tfh cells. Our results implicate PTEN in platelet-mediated immune homeostasis, and provide evidence that hyperactive platelets function as an important mediator in autoimmune diseases using mouse models.
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Affiliation(s)
- Xue Chen
- School of Life Sciences, Shanghai University, 333 Nanchen Road, Shanghai, 200444, China.
| | - Yanyan Xu
- Department of Biochemistry and Molecular Cell Biology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Qidi Chen
- Department of Biochemistry and Molecular Cell Biology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Heng Zhang
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Yu Zeng
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Yan Geng
- Department of Biochemistry and Molecular Cell Biology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Lei Shen
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Fubin Li
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Lei Chen
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Guo-Qiang Chen
- Department of Biochemistry and Molecular Cell Biology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China
| | - Chuanxin Huang
- Shanghai Institute of Immunology, Department of Immunology and Microbiology, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China.
| | - Junling Liu
- Department of Biochemistry and Molecular Cell Biology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University School of Medicine, 280 South Chongqing Road, Shanghai, 200025, China.
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11
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Procoagulant platelet sentinels prevent inflammatory bleeding through GPIIBIIIA and GPVI. Blood 2022; 140:121-139. [PMID: 35472164 DOI: 10.1182/blood.2021014914] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Accepted: 04/12/2022] [Indexed: 11/20/2022] Open
Abstract
Impairment of vascular integrity is a hallmark of inflammatory diseases. We recently reported that single immune-responsive platelets migrate and re-position themselves to sites of vascular injury to prevent bleeding. However, it remains unclear how single platelets preserve vascular integrity once encountering endothelial breaches. Here we demonstrate by intravital microscopy combined with genetic mouse models that procoagulant activation (PA) of single platelets and subsequent recruitment of the coagulation cascade are crucial for the prevention of inflammatory bleeding. Using a novel lactadherin-based compound we detect phosphatidylserine (PS)-positive procoagulant platelets in the inflamed vasculature. We identify exposed collagen as the central trigger arresting platelets and initiating subsequent PA in a CypD- and TMEM16F-dependent manner both in vivo and in vitro. Platelet PA promotes binding of the prothrombinase complex to the platelet membrane, greatly enhancing thrombin activity resulting in fibrin formation. PA of migrating platelets is initiated by co-stimulation via integrin αIIbβ3 (GPIIBIIIA)/Gα13-mediated outside-in-signaling and GPVI signaling, leading to an above-threshold intracellular calcium release. This effectively targets the coagulation cascade to breaches of vascular integrity identified by patrolling platelets. Platelet-specific genetic loss of either CypD or TMEM16F as well as combined blockade of platelet GPIIBIIIA and GPVI reduce platelet PA in vivo and aggravate pulmonary inflammatory hemorrhage. Our findings illustrate a novel role of procoagulant platelets in the prevention of inflammatory bleeding and provide evidence that PA of patrolling platelet sentinels effectively targets and confines activation of coagulation to breaches of vascular integrity.
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12
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Zaid Y, Merhi Y. Implication of Platelets in Immuno-Thrombosis and Thrombo-Inflammation. Front Cardiovasc Med 2022; 9:863846. [PMID: 35402556 PMCID: PMC8990903 DOI: 10.3389/fcvm.2022.863846] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Accepted: 03/04/2022] [Indexed: 12/14/2022] Open
Abstract
In addition to their well-described hemostatic function, platelets are active participants in innate and adaptive immunity. Inflammation and immunity are closely related to changes in platelet reactions and enhanced platelet function in thrombo-inflammation, as well as in microbial and virus infections. A platelet’s immune function is incompletely understood, but an important balance exists between its protective and pathogenic responses and its thrombotic and inflammatory functions. As the mediator of vascular homeostasis, platelets interact with neutrophils, bacteria and virus by expressing specific receptors and releasing granules, transferring RNA, and secreting mitochondria, which controls hemostasis and thrombosis, infection, and innate and adaptive immunity. This review focuses on the involvement of platelets during immuno-thrombosis and thrombo-inflammation.
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Affiliation(s)
- Younes Zaid
- Laboratory of Materials, Nanotechnology and Environment, Faculty of Sciences, Mohammed V University in Rabat, Rabat, Morocco.,Immunology and Biodiversity Laboratory, Department of Biology, Faculty of Sciences, Hassan II University, Casablanca, Morocco
| | - Yahye Merhi
- Laboratory of Thrombosis and Hemostasis, Montreal Heart Institute, Research Center, The Université de Montréal, Montreal, QC, Canada
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13
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Al-Tamimi AO, Yusuf AM, Jayakumar MN, Ansari AW, Elhassan M, AbdulKarim F, Kannan M, Halwani R, Ahmad F. SARS-CoV-2 infection induces soluble platelet activation markers and PAI-1 in the early moderate stage of COVID-19. Int J Lab Hematol 2022; 44:712-721. [PMID: 35266284 PMCID: PMC9111479 DOI: 10.1111/ijlh.13829] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 01/29/2022] [Accepted: 03/02/2022] [Indexed: 01/08/2023]
Abstract
Introduction Coagulation dysfunction and thromboembolism emerge as strong comorbidity factors in severe COVID‐19. However, it is unclear when particularly platelet activation markers and coagulation factors dysregulated during the pathogenesis of COVID‐19. Here, we sought to assess the levels of coagulation and platelet activation markers at moderate and severe stages of COVID‐19 to understand the pathogenesis. Methods To understand this, hospitalized COVID‐19 patients with (severe cases that required intensive care) or without pneumonia (moderate cases) were recruited. Phenotypic and molecular characterizations were performed employing basic coagulation tests including prothrombin time (PT), activated partial thromboplastin time (APTT), D‐Dimer, and tissue factor pathway inhibitor (TFPI). The flow cytometry‐based multiplex assays were performed to assess FXI, anti‐thrombin, prothrombin, fibrinogen, FXIII, P‐selectin, sCD40L, plasminogen, tissue plasminogen activator (tPA), plasminogen activator inhibitor‐1 (PAI‐1), and D‐Dimer. Results The investigations revealed induction of plasma P‐selectin and CD40 ligand (sCD40L) in moderate COVID‐19 cases, which were significantly abolished with the progression of COVID‐19 severity. Moreover, a profound reduction in plasma tissue factor pathway inhibitor (TFPI) and FXIII were identified particularly in the severe COVID‐19. Further analysis revealed fibrinogen induction in both moderate and severe patients. Interestingly, an elevated PAI‐1 more prominently in moderate, and tPA particularly in severe COVID‐19 cases were observed. Particularly, the levels of fibrinogen and tPA directly correlated with the severity of the disease. Conclusions In summary, induction of soluble P‐selectin, sCD40L, fibrinogen, and PAI‐1 suggests the activation of platelets and coagulation system at the moderate stage before COVID‐19 patients require intensive care. These findings would help in designing better thromboprophylaxis to limit the COVID‐19 severity.
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Affiliation(s)
- Abaher O Al-Tamimi
- Cardiovascular Research Group, Sharjah Institute for Medical Research, University of Sharjah, Sharjah, UAE
| | - Ayesha M Yusuf
- Cardiovascular Research Group, Sharjah Institute for Medical Research, University of Sharjah, Sharjah, UAE
| | - Manju N Jayakumar
- Cardiovascular Research Group, Sharjah Institute for Medical Research, University of Sharjah, Sharjah, UAE
| | - Abdul W Ansari
- Cardiovascular Research Group, Sharjah Institute for Medical Research, University of Sharjah, Sharjah, UAE.,Dermatology Institute, Translational Research Institute, Academic Health Systems, Hamad Medical Corporation, Doha, Qatar
| | - Mona Elhassan
- Department of Internal Medicine, Rashid Hospital, Dubai, UAE
| | | | - Meganathan Kannan
- Blood and Vascular Biology Research Lab, Department of Life Sciences, Central University of Tamil Nadu, Thiruvarur, India
| | - Rabih Halwani
- Department of Basic Medical Sciences, College of Medicine, University of Sharjah, Sharjah, UAE
| | - Firdos Ahmad
- Cardiovascular Research Group, Sharjah Institute for Medical Research, University of Sharjah, Sharjah, UAE.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, UAE
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14
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Johnson BZ, Stevenson AW, Barrett LW, Fear MW, Wood FM, Linden MD. Platelets after burn injury - hemostasis and beyond. Platelets 2022; 33:655-665. [PMID: 34986759 DOI: 10.1080/09537104.2021.1981849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Burn injuries are common and often life-threatening trauma. With this trauma comes an interruption of normal hemostasis, with distinct impacts on platelets. Our interest in the relationships between burn injury and platelet function stems from two key perspectives: platelet function is a vital component of acute responses to injury, and furthermore the incidence of cardiovascular disease (CVD) is higher in burn survivors compared to the general population. This review explores the impact of burn injury on coagulation, platelet function, and the participation of platelets in immunopathology. Potential avenues of further research are explored, and consideration is given to what therapies may be appropriate for mediating post-burn thrombopathology.
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Affiliation(s)
- B Z Johnson
- Burn Injury Research Unit, University of Western Australia, Perth, Australia.,School of Biomedical Science, University of Western Australia, Perth, Australia
| | - A W Stevenson
- Burn Injury Research Unit, University of Western Australia, Perth, Australia.,School of Biomedical Science, University of Western Australia, Perth, Australia
| | - L W Barrett
- Burn Injury Research Unit, University of Western Australia, Perth, Australia.,Telethon Kids Institute, University of Western Australia, Perth, Australia
| | - M W Fear
- Burn Injury Research Unit, University of Western Australia, Perth, Australia.,School of Biomedical Science, University of Western Australia, Perth, Australia
| | - F M Wood
- Burn Injury Research Unit, University of Western Australia, Perth, Australia.,Burns Service of Western Australia, Wa Department of Health, Nedlands, Australia
| | - M D Linden
- School of Biomedical Science, University of Western Australia, Perth, Australia
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15
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Comprehensive analysis of differentially expressed mRNA and circRNA in Ankylosing spondylitis patients' platelets. Exp Cell Res 2021; 409:112895. [PMID: 34717918 DOI: 10.1016/j.yexcr.2021.112895] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 10/18/2021] [Accepted: 10/24/2021] [Indexed: 12/15/2022]
Abstract
Ankylosing spondylitis (AS) is a chronic inflammatory disease significantly decreasing the quality of life. Platelets play an important and active role in the development of AS. Accumulating evidence demonstrated platelets contain diverse RNA repository inherited from megakaryocytes or microvesicles. Platelet RNAs are dynamically affected by pathological conditions and could be used as diagnostic or prognostic biomarkers. However, the role of the platelet RNAs in AS is elusive. In this study, we compared mRNA and circRNA profiles in platelets between AS patients and healthy controls using RNA sequencing and bioinformatic analysis, and found 4996 mRNAs and 2942 circRNAs were differently expressed. The significantly over-expressed mRNAs in AS patients are involved in platelet activity, gap junction, focal adhesion, rap1 and toll and Imd signaling pathway. The previous identified platelet-derived immune mediators such as P2Y1, P2Y12, PF4, GPIbα, CD40L, ICAM2, CCL5 (RANTES), TGF-β (TGF-β1 and TGF-β2) and PDGF (PDGFB and PDGFA) are also included in these over expressed mRNAs, implying these factors may trigger inflammatory cascades and promote the development of AS. Additionally, we found two down-regulated circRNA (circPTPN22 and circFCHSD2) from the intersection analyses of platelets and spinal ligament tissues of AS patients. The circRNA-miRNA-mRNA regulatory network of these two circRNAs was constructed, and the target mRNAs were enriched in Th17 cell differentiation, inflammatory bowel disease, cell adhesion molecules, cytokine-cytokine receptor interaction, Jak-STAT and Wnt signaling pathway, all these pathways participate in the bone remodeling and pro/anti-inflammatory immune regulation in AS. Then, qRT-PCR was performed to validate the expression of selected key mRNAs and circRNAs and the results demonstrated that the expression levels of P2Y12, GPIbα, circPTPN22 and circFCHSD2 were consistent with the sequencing analysis. In addition, the high expression of five predicted miRNAs interacting with circPTPN22 and circFCHSD2 were also detected in AS by qRT-PCR. Taken together, our study presents a comprehensive overview of mRNAs and circRNAs in platelets in AS patients and offers new insight into the mechanisms of platelet involving in the pathogenesis of AS. The mRNAs and circRNAs identified in this study may serve as candidates for diagnosis and targeted treatment of AS.
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16
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TGF-β signaling and the interaction between platelets and T-cells in tumor microenvironment: Foes or friends? Cytokine 2021; 150:155772. [PMID: 34814016 DOI: 10.1016/j.cyto.2021.155772] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Revised: 10/17/2021] [Accepted: 11/15/2021] [Indexed: 01/07/2023]
Abstract
T-cells, as the main immune cells in fighting against cancer cells, are usually overwhelmed by many factors. Tumor microenvironment (TME) changes are one of the factors that can limit T-cells functions. On the other hand, platelets which are known as the main source of transforming growth factor-β (TGF-β) in TME, are seemingly insignificant immune cells that can affect T-cell functions. There is a hypothesis that platelets might prevent tumor growth by stimulating cellular immunity, especially T-cells in pre-cancer status while they can inhibit T-cells and stimulate tumor growth in the advanced stage of cancer. Therefore, platelets could act as a double-edged sword in the activation of T-cells under pre-cancer and advanced stages of cancer conditions. In this review, the interaction between platelets and T cells in pre-cancer and advanced stages of cancer and the role of TGF-β signaling in different stages of cancer will be discussed.
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17
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Pathogen-reduced PRP blocks T-cell activation, induces Treg cells, and promotes TGF-β expression by cDCs and monocytes in mice. Blood Adv 2020; 4:5547-5561. [PMID: 33166410 DOI: 10.1182/bloodadvances.2020002867] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 10/14/2020] [Indexed: 02/06/2023] Open
Abstract
Alloimmunization against platelet-rich plasma (PRP) transfusions can lead to complications such as platelet refractoriness or rejection of subsequent transfusions and transplants. In mice, pathogen reduction treatment of PRP with UVB light and riboflavin (UV+R) prevents alloimmunization and appears to induce partial antigen-specific tolerance to subsequent transfusions. Herein, the in vivo responses of antigen-presenting cells and T cells to transfusion with UV+R-treated allogeneic PRP were evaluated to understand the cellular immune responses leading to antigen-specific tolerance. Mice that received UV+R-treated PRP had significantly increased transforming growth factor β (TGF-β) expression by CD11b+ CD4+ CD11cHi conventional dendritic cells (cDCs) and CD11bHi monocytes (P < .05). While robust T-cell responses to transfusions with untreated allogeneic PRP were observed (P < .05), these were blocked by UV+R treatment. Mice given UV+R-treated PRP followed by untreated PRP showed an early significant (P < .01) enrichment in regulatory T (Treg) cells and associated TGF-β production as well as diminished effector T-cell responses. Adoptive transfer of T-cell-enriched splenocytes from mice given UV+R-treated PRP into naive recipients led to a small but significant reduction of CD8+ T-cell responses to subsequent allogeneic transfusion. These data demonstrate that pathogen reduction with UV+R induces a tolerogenic profile by way of CD11b+ CD4+ cDCs, monocytes, and induction of Treg cells, blocking T-cell activation and reducing secondary T-cell responses to untreated platelets in vivo.
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18
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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: 76] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [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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19
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Chen J, Tan W. Platelet activation and immune response in diabetic microangiopathy. Clin Chim Acta 2020; 507:242-247. [DOI: 10.1016/j.cca.2020.04.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 04/29/2020] [Accepted: 04/29/2020] [Indexed: 01/19/2023]
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20
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Page MJ, Pretorius E. A Champion of Host Defense: A Generic Large-Scale Cause for Platelet Dysfunction and Depletion in Infection. Semin Thromb Hemost 2020; 46:302-319. [PMID: 32279287 PMCID: PMC7339151 DOI: 10.1055/s-0040-1708827] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Thrombocytopenia is commonly associated with sepsis and infections, which in turn are characterized by a profound immune reaction to the invading pathogen. Platelets are one of the cellular entities that exert considerable immune, antibacterial, and antiviral actions, and are therefore active participants in the host response. Platelets are sensitive to surrounding inflammatory stimuli and contribute to the immune response by multiple mechanisms, including endowing the endothelium with a proinflammatory phenotype, enhancing and amplifying leukocyte recruitment and inflammation, promoting the effector functions of immune cells, and ensuring an optimal adaptive immune response. During infection, pathogens and their products influence the platelet response and can even be toxic. However, platelets are able to sense and engage bacteria and viruses to assist in their removal and destruction. Platelets greatly contribute to host defense by multiple mechanisms, including forming immune complexes and aggregates, shedding their granular content, and internalizing pathogens and subsequently being marked for removal. These processes, and the nature of platelet function in general, cause the platelet to be irreversibly consumed in the execution of its duty. An exaggerated systemic inflammatory response to infection can drive platelet dysfunction, where platelets are inappropriately activated and face immunological destruction. While thrombocytopenia may arise by condition-specific mechanisms that cause an imbalance between platelet production and removal, this review evaluates a generic large-scale mechanism for platelet depletion as a repercussion of its involvement at the nexus of responses to infection.
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Affiliation(s)
- Martin J Page
- Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Etheresia Pretorius
- Department of Physiological Sciences, Stellenbosch University, Stellenbosch, South Africa
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21
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Colberg L, Cammann C, Greinacher A, Seifert U. Structure and function of the ubiquitin-proteasome system in platelets. J Thromb Haemost 2020; 18:771-780. [PMID: 31898400 DOI: 10.1111/jth.14730] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 12/30/2019] [Indexed: 12/16/2022]
Abstract
Platelets are small anucleate blood cells with a life span of 7 to 10 days. They are main regulators of hemostasis. Balanced platelet activity is crucial to prevent bleeding or occlusive thrombus formation. Growing evidence supports that platelets also participate in immune reactions, and interaction between platelets and leukocytes contributes to both thrombosis and inflammation. The ubiquitin-proteasome system (UPS) plays a key role in maintaining cellular protein homeostasis by its ability to degrade non-functional self-, foreign, or short-lived regulatory proteins. Platelets express standard and immunoproteasomes. Inhibition of the proteasome impairs platelet production and platelet function. Platelets also express major histocompatibility complex (MHC) class I molecules. Peptide fragments released by proteasomes can bind to MHC class I, which makes it also likely that platelets can activate epitope specific cytotoxic T lymphocytes (CTLs). In this review, we focus on current knowledge on the significance of the proteasome for the functions of platelets as critical regulators of hemostasis as well as modulators of the immune response.
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Affiliation(s)
- Lisa Colberg
- Friedrich Loeffler Institut für Medizinische Mikrobiologie-Virologie, Universitätsmedizin Greifswald, Greifswald, Germany
- Institut für Immunologie und Transfusionsmedizin, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Clemens Cammann
- Friedrich Loeffler Institut für Medizinische Mikrobiologie-Virologie, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Andreas Greinacher
- Institut für Immunologie und Transfusionsmedizin, Universitätsmedizin Greifswald, Greifswald, Germany
| | - Ulrike Seifert
- Friedrich Loeffler Institut für Medizinische Mikrobiologie-Virologie, Universitätsmedizin Greifswald, Greifswald, Germany
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22
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Abstract
Dysregulation of lymphocyte function, accumulation of autoantibodies and defective clearance of circulating immune complexes and apoptotic cells are hallmarks of systemic lupus erythematosus (SLE). Moreover, it is now evident that an intricate interplay between the adaptive and innate immune systems contributes to the pathogenesis of SLE, ultimately resulting in chronic inflammation and organ damage. Platelets circulate in the blood and are chiefly recognized for their role in the prevention of bleeding and promotion of haemostasis; however, accumulating evidence points to a role for platelets in both adaptive and innate immunity. Through a broad repertoire of receptors, platelets respond promptly to immune complexes, complement and damage-associated molecular patterns, and represent a major reservoir of immunomodulatory molecules in the circulation. Furthermore, evidence suggests that platelets are activated in patients with SLE, and that they could contribute to the circulatory autoantigenic load through the release of microparticles and mitochondrial antigens. Herein, we highlight how platelets contribute to the immune response and review evidence implicating platelets in the pathogenesis of SLE.
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23
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Liu X, Gorzelanny C, Schneider SW. Platelets in Skin Autoimmune Diseases. Front Immunol 2019; 10:1453. [PMID: 31333641 PMCID: PMC6620619 DOI: 10.3389/fimmu.2019.01453] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Accepted: 06/10/2019] [Indexed: 12/11/2022] Open
Abstract
Systemic lupus erythematosus (SLE), systemic sclerosis (SSc), and small vessel vasculitis are three autoimmune diseases frequently manifested in the skin. They share common pathogenic features, including production of autoantibodies, loss of tolerance to self-antigens, tissue necrosis and fibrosis, vasculopathy and activation of the coagulation system. Platelets occupy a central part within the coagulation cascade and are well-recognized for their hemostatic role. However, recent cumulative evidence implicates their additional and multifaceted immunoregulatory functions. Platelets express immune receptors and they store growth factors, cytokines, and chemokines in their granules enabling a significant contribution to inflammation. A plethora of activating triggers such as damage associated molecular patterns (DAMPs) released from damaged endothelial cells, immune complexes, or complement effector molecules can mediate platelet activation. Activated platelets further foster an inflammatory environment and the crosstalk with the endothelium and leukocytes by the release of immunoactive molecules and microparticles. Further insight into the pathogenic implications of platelet activation will pave the way for new therapeutic strategies targeting autoimmune diseases. In this review, we discuss the inflammatory functions of platelets and their mechanistic contribution to the pathophysiology of SSc, ANCA associated small vessel vasculitis and other autoimmune diseases affecting the skin.
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Affiliation(s)
- Xiaobo Liu
- Department of Dermatology, Medical Faculty Mannheim, University of Heidelberg, Mannheim, Germany.,Department of Dermatology and Venereology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Christian Gorzelanny
- Department of Dermatology and Venereology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Stefan W Schneider
- Department of Dermatology and Venereology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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24
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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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25
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Morrell CN, Pariser DN, Hilt ZT, Vega Ocasio D. The Platelet Napoleon Complex-Small Cells, but Big Immune Regulatory Functions. Annu Rev Immunol 2018; 37:125-144. [PMID: 30485751 DOI: 10.1146/annurev-immunol-042718-041607] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Platelets have dual physiologic roles as both cellular mediators of thrombosis and immune modulatory cells. Historically, the thrombotic function of platelets has received significant research and clinical attention, but emerging research indicates that the immune regulatory roles of platelets may be just as important. We now know that in addition to their role in the acute thrombotic event at the time of myocardial infarction, platelets initiate and accelerate inflammatory processes that are part of the pathogenesis of atherosclerosis and myocardial infarction expansion. Furthermore, it is increasingly apparent from recent studies that platelets impact the pathogenesis of many vascular inflammatory processes such as autoimmune diseases, sepsis, viral infections, and growth and metastasis of many types of tumors. Therefore, we must consider platelets as immune cells that affect all phases of immune responses.
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Affiliation(s)
- Craig N Morrell
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine, Rochester, New York 14642, USA;
| | - Daphne N Pariser
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine, Rochester, New York 14642, USA;
| | - Zachary T Hilt
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine, Rochester, New York 14642, USA;
| | - Denisse Vega Ocasio
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine, Rochester, New York 14642, USA;
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26
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Eisinger F, Patzelt J, Langer HF. The Platelet Response to Tissue Injury. Front Med (Lausanne) 2018; 5:317. [PMID: 30483508 PMCID: PMC6242949 DOI: 10.3389/fmed.2018.00317] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 10/23/2018] [Indexed: 12/16/2022] Open
Abstract
In recent years, various studies have increasingly explained platelet functions not only in their central role as a regulator in cellular hemostasis and coagulation. In fact, there is growing evidence that under specific conditions, platelets act as a mediator between the vascular system, hemostasis, and the immune system. Therefore, they are essential in many processes involved in tissue remodeling and tissue reorganization after injury or inflammatory responses. These processes include the promotion of inflammatory processes, the contribution to innate and adaptive immune responses during bacterial and viral infections, the modulation of angiogenesis, and the regulation of cell apoptosis in steady-state tissue homeostasis or after tissue breakdown. All in all platelets may contribute to the control of tissue homeostasis much more than generally assumed. This review summarizes the current knowledge of platelets as part of the tissue remodeling network and seeks to provide possible translational implications for clinical therapy.
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Affiliation(s)
- Felix Eisinger
- Section for Cardioimmunology, Department of Cardiovascular Medicine, University of Tuebingen, Tübingen, Germany
| | - Johannes Patzelt
- University Clinic for Cardiovascular Medicine, University of Tuebingen, Tübingen, Germany
| | - Harald F. Langer
- Section for Cardioimmunology, Department of Cardiovascular Medicine, University of Tuebingen, Tübingen, Germany
- University Clinic for Cardiovascular Medicine, University of Tuebingen, Tübingen, Germany
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27
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Nurden A. Platelets, inflammation and tissue regeneration. Thromb Haemost 2017; 105 Suppl 1:S13-33. [DOI: 10.1160/ths10-11-0720] [Citation(s) in RCA: 469] [Impact Index Per Article: 67.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Accepted: 02/04/2011] [Indexed: 12/20/2022]
Abstract
SummaryBlood platelets have long been recognised to bring about primary haemostasis with deficiencies in platelet production and function manifesting in bleeding while upregulated function favourises arterial thrombosis. Yet increasing evidence indicates that platelets fulfil a much wider role in health and disease. First, they store and release a wide range of biologically active substances including the panoply of growth factors, chemokines and cytokines released from α-granules. Membrane budding gives rise to microparticles (MPs), another active participant within the blood stream. Platelets are essential for the innate immune response and combat infection (viruses, bacteria, micro-organisms). They help maintain and modulate inflammation and are a major source of pro-inflammatory molecules (e.g. P-selectin, tissue factor, CD40L, metalloproteinases). As well as promoting coagulation, they are active in fibrinolysis; wound healing, angiogenesis and bone formation as well as in maternal tissue and foetal vascular remodelling. Activated platelets and MPs intervene in the propagation of major diseases. They are major players in atherosclerosis and related diseases, pathologies of the central nervous system (Alzheimers disease, multiple sclerosis), cancer and tumour growth. They participate in other tissue-related acquired pathologies such as skin diseases and allergy, rheumatoid arthritis, liver disease; while, paradoxically, autologous platelet-rich plasma and platelet releasate are being used as an aid to promote tissue repair and cellular growth. The above mentioned roles of platelets are now discussed.
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Sonmez O, Sonmez M. Role of platelets in immune system and inflammation. Porto Biomed J 2017; 2:311-314. [PMID: 32258788 DOI: 10.1016/j.pbj.2017.05.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 05/31/2017] [Indexed: 10/18/2022] Open
Abstract
Platelets have significant role in modulating clot formation. Additionally, emerging data indicates that platelets have considerable roles in inflammation and immune response. Platelets gather at the damaged cite and adhere to white blood cells. Subsequently, they release cytokines and chemokines which are chemotactic for neutrophils and monocytes. Therefore, platelets are necessary for targeting lymphocytes, neutrophils and monocytes to inflammation site. Those interactions enhance inflammation. Moreover, platelets serve as an immune cell by engulfing microbes. Presence of platelets affect prognosis in some bacterial or viral infection and several other diseases.
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Affiliation(s)
- Ozge Sonmez
- Istanbul University Cerrahpasa Medicine Faculty, English Medicine Programme, Istanbul, Turkey
| | - Mehmet Sonmez
- Karadeniz Technical University, School of Medicine, Department of Haematology, Trabzon, Turkey
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Affiliation(s)
- R. Kapur
- Division of Hematology and Transfusion Medicine; Lund University; Lund Sweden
| | - J. W. Semple
- Division of Hematology and Transfusion Medicine; Lund University; Lund Sweden
- Keenan Research Centre for Biomedical Science; St. Michael's Hospital; Toronto ON Canada
- Departments of Pharmacology, Medicine and Laboratory Medicine and Pathobiology; University of Toronto; Toronto ON Canada
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Formulation of the bivalent prostate cancer vaccine with surgifoam elicits antigen-specific effector T cells in PSA-transgenic mice. Vaccine 2017; 35:5794-5798. [PMID: 28939158 DOI: 10.1016/j.vaccine.2017.09.037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 08/07/2017] [Accepted: 09/12/2017] [Indexed: 11/24/2022]
Abstract
We previously developed and characterized an adenoviral-based prostate cancer vaccine for simultaneous targeting of prostate-specific antigen (PSA) and prostate stem cell antigen (PSCA). We also demonstrated that immunization of mice with the bivalent vaccine (Ad5-PSA+PSCA) inhibited the growth of established prostate tumors. However, there are multiple challenges hindering the success of immunological therapies in the clinic. One of the prime concerns has been to overcome the immunological tolerance and maintenance of long-term effector T cells. In this study, we further characterized the use of the bivalent vaccine (Ad5-PSA+PSCA) in a transgenic mouse model expressing human PSA in the mouse prostate. We demonstrated the expression of PSA analyzed at the mRNA level (by RT-PCR) and protein level (by immunohistochemistry) in the prostate lobes harvested from the PSA-transgenic (PSA-Tg) mice. We established that the administration of the bivalent vaccine in surgifoam to the PSA-Tg mice induces strong PSA-specific effector CD8+ T cells as measured by IFN-γ secretion and in vitro cytotoxic T-cell assay. Furthermore, the use of surgifoam with Ad5-PSA+PSCA vaccine allows multiple boosting vaccinations with a significant increase in antigen-specific CD8+ T cells. These observations suggest that the formulation of the bivalent prostate cancer vaccine (Ad5-PSA+PSCA) with surgifoam bypasses the neutralizing antibody response, thus allowing multiple boosting. This formulation is also helpful for inducing an antigen-specific immune response in the presence of self-antigen, and maintains long-term effector CD8+ T cells.
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31
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The potential role of platelets in the consensus molecular subtypes of colorectal cancer. Cancer Metastasis Rev 2017; 36:273-288. [DOI: 10.1007/s10555-017-9678-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Michel NA, Zirlik A, Wolf D. CD40L and Its Receptors in Atherothrombosis-An Update. Front Cardiovasc Med 2017; 4:40. [PMID: 28676852 PMCID: PMC5477003 DOI: 10.3389/fcvm.2017.00040] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 05/29/2017] [Indexed: 12/30/2022] Open
Abstract
CD40L (CD154), a member of the tumor necrosis factor superfamily, is a co-stimulatory molecule that was first discovered on activated T cells. Beyond its fundamental role in adaptive immunity-ligation of CD40L to its receptor CD40 is a prerequisite for B cell activation and antibody production-evidence from more than two decades has expanded our understanding of CD40L as a powerful modulator of inflammatory pathways. Although inhibition of CD40L with neutralizing antibodies has induced life-threatening side effects in clinical trials, the discovery of cell-specific effects and novel receptors with distinct functional consequences has opened a new path for therapies that specifically target detrimental properties of CD40L. Here, we carefully evaluate the signaling network of CD40L by gene enrichment analysis and its cell-specific expression, and thoroughly discuss its role in cardiovascular pathologies with a specific emphasis on atherosclerotic and thrombotic disease.
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Affiliation(s)
- Nathaly Anto Michel
- Faculty of Medicine, Department of Cardiology and Angiology I, Heart Center Freiburg, University of Freiburg, Freiburg, Germany
| | - Andreas Zirlik
- Faculty of Medicine, Department of Cardiology and Angiology I, Heart Center Freiburg, University of Freiburg, Freiburg, Germany
| | - Dennis Wolf
- Faculty of Medicine, Department of Cardiology and Angiology I, Heart Center Freiburg, University of Freiburg, Freiburg, Germany
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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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Abstract
Publisher's Note: This article has a companion Point by Brass et al. Publisher's Note: Join in the discussion of these articles at Blood Advances Community Conversations.
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Ferdous F, Saski C, Bridges W, Burns M, Dunn H, Elliott K, Scott TR. Transcriptome Profile of the Chicken Thrombocyte: New Implications as an Advanced Immune Effector Cell. PLoS One 2016; 11:e0163890. [PMID: 27711235 PMCID: PMC5053482 DOI: 10.1371/journal.pone.0163890] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 09/18/2016] [Indexed: 12/30/2022] Open
Abstract
Thrombocytes are nucleated platelets involved in immune functions such as pathogen recognition and release of pro-inflammatory bioactive compounds when exposed to bacterial and viral molecules. However, the complete role of these cells in innate and adaptive immune responses is not understood, and little is known about their biology at the molecular-genetic level. Highly sensitive RNA-sequencing technologies were used to analyze the complete transcriptome of thrombocytes for the first time with analytical resolution focused on cell-based components of the immune system/response. Amongst all the genes listed in the current chicken genome assembly, 10,041 gene transcripts were found in the chicken thrombocyte. After 1-hour in vitro stimulation with lipopolysaccharide (LPS, Salmonella minnesota), 490 genes were upregulated and 359 genes were downregulated, respectively, with at least a 1-fold change relative to unexposed thrombocytes. Additionally, by constructing a de novo assembly, we were able to identify a total of 3,030 novel genes in the thrombocyte transcriptome. The information generated here is useful in development of novel solutions to lower the economic burden and zoonotic threat that accompanies infectious diseases for birds and fish. In addition, the resources created here have translational utility as a model system to find orthologous genes and genes related to its enucleated counterpart, the platelet.
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Affiliation(s)
- Farzana Ferdous
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, South Carolina, United States of America
| | - Christopher Saski
- Clemson University Genomics Institute, Clemson University, Clemson, South Carolina, United States of America
| | - William Bridges
- Department of Mathematical Sciences, Clemson University, Clemson, South Carolina, United States of America
| | - Matthew Burns
- Clemson Cooperative Extension, Clemson University, Clemson, South Carolina, United States of America
| | - Heather Dunn
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, South Carolina, United States of America
| | - Kathryn Elliott
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, South Carolina, United States of America
| | - Thomas R. Scott
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, South Carolina, United States of America
- * E-mail:
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36
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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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37
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Abstract
Platelets are megakaryocyte-derived cellular fragments, which lack a nucleus and are the smallest circulating cells and are classically known to have a major role in supporting hemostasis. Apart from this well-established role, it is now becoming evident that platelets are also capable of conveying other important functions, such as during infection and inflammation. This paper will outline these nonhemostatic functions in two major sections termed "Platelets versus pathogens" and "Platelet-target cell communication". Platelets actively contribute to protection against invading pathogens and are capable of regulating immune functions in various target cells, all through sophisticated and efficient mechanisms. These relatively novel features will be highlighted, illustrating the multifunctional role of platelets in inflammation.
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Affiliation(s)
- Rick Kapur
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael׳s Hospital, Canadian Blood Services, Toronto, Ontario, Canada
| | - John W Semple
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael׳s Hospital, Canadian Blood Services, Toronto, Ontario, Canada; Departments of Pharmacology, Medicine, and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada.
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38
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Kapur R, Zufferey A, Boilard E, Semple JW. Nouvelle cuisine: platelets served with inflammation. THE JOURNAL OF IMMUNOLOGY 2015; 194:5579-87. [PMID: 26048965 DOI: 10.4049/jimmunol.1500259] [Citation(s) in RCA: 214] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Platelets are small cellular fragments with the primary physiological role of maintaining hemostasis. In addition to this well-described classical function, it is becoming increasingly clear that platelets have an intimate connection with infection and inflammation. This stems from several platelet characteristics, including their ability to bind infectious agents and secrete many immunomodulatory cytokines and chemokines, as well as their expression of receptors for various immune effector and regulatory functions, such as TLRs, which allow them to sense pathogen-associated molecular patterns. Furthermore, platelets contain RNA that can be nascently translated under different environmental stresses, and they are able to release membrane microparticles that can transport inflammatory cargo to inflammatory cells. Interestingly, acute infections can also result in platelet breakdown and thrombocytopenia. This report highlights these relatively new aspects of platelets and, thus, their nonhemostatic nature in an inflammatory setting.
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Affiliation(s)
- Rick Kapur
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada; Canadian Blood Services, Toronto, Ontario M5B 1W8, Canada
| | - Anne Zufferey
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada
| | - Eric Boilard
- Centre de Recherche en Rhumatologie et Immunologie, Centre de Recherche du Centre Hospitalier Universitaire de Québec, Faculté de Médecine de l'Université Laval, Quebec City, Quebec G1V 4G2, Canada
| | - John W Semple
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario M5B 1W8, Canada; Canadian Blood Services, Toronto, Ontario M5B 1W8, Canada; Department of Pharmacology, University of Toronto, Toronto, Ontario M5B 1W8, Canada; Department of Medicine, University of Toronto, Toronto, Ontario M5B 1W8, Canada; and Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario M5B 1W8, Canada
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39
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Thomas MR, Storey RF. The role of platelets in inflammation. Thromb Haemost 2015; 114:449-58. [PMID: 26293514 DOI: 10.1160/th14-12-1067] [Citation(s) in RCA: 336] [Impact Index Per Article: 37.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2014] [Accepted: 08/07/2015] [Indexed: 12/18/2022]
Abstract
There is growing recognition of the critical role of platelets in inflammation and immune responses. Recent studies have indicated that antiplatelet medications may reduce mortality from infections and sepsis, which suggests possible clinical relevance of modifying platelet responses to inflammation. Platelets release numerous inflammatory mediators that have no known role in haemostasis. Many of these mediators modify leukocyte and endothelial responses to a range of different inflammatory stimuli. Additionally, platelets form aggregates with leukocytes and form bridges between leukocytes and endothelium, largely mediated by platelet P-selectin. Through their interactions with monocytes, neutrophils, lymphocytes and the endothelium, platelets are therefore important coordinators of inflammation and both innate and adaptive immune responses.
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Affiliation(s)
- Mark R Thomas
- Dr. Mark R. Thomas, BMedSci BMBS MRCP, Department of Cardiovascular Science, University of Sheffield, Beech Hill Road, Sheffield, S10 2RX, UK, Tel.: +44 114 3052019, Fax: +44 114 2266159, E-mail
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40
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Affiliation(s)
- L. H. Boudreau
- Centre de Recherche en Rhumatologie et Immunologie; Centre de Recherche du Centre Hospitalier Universitaire de Québec; Faculté de Médecine de l'Université Laval; Québec QC Canada
| | - G. Marcoux
- Centre de Recherche en Rhumatologie et Immunologie; Centre de Recherche du Centre Hospitalier Universitaire de Québec; Faculté de Médecine de l'Université Laval; Québec QC Canada
| | - E. Boilard
- Centre de Recherche en Rhumatologie et Immunologie; Centre de Recherche du Centre Hospitalier Universitaire de Québec; Faculté de Médecine de l'Université Laval; Québec QC Canada
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41
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Dewitte A, Tanga A, Villeneuve J, Lepreux S, Ouattara A, Desmoulière A, Combe C, Ripoche J. New frontiers for platelet CD154. Exp Hematol Oncol 2015; 4:6. [PMID: 25763299 PMCID: PMC4355125 DOI: 10.1186/s40164-015-0001-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 02/03/2015] [Indexed: 02/07/2023] Open
Abstract
The role of platelets extends beyond hemostasis. The pivotal role of platelets in inflammation has shed new light on the natural history of conditions associated with acute or chronic inflammation. Beyond the preservation of vascular integrity, platelets are essential to tissue homeostasis and platelet-derived products are already used in the clinics. Unanticipated was the role of platelets in the adaptative immune response, allowing a renewed conceptual approach of auto-immune diseases. Platelets are also important players in cancer growth and dissemination. Platelets fulfill most of their functions through the expression of still incompletely characterized membrane-bound or soluble mediators. Among them, CD154 holds a peculiar position, as platelets represent a major source of CD154 and as CD154 contributes to most of these new platelet attributes. Here, we provide an overview of some of the new frontiers that the study of platelet CD154 is opening, in inflammation, tissue homeostasis, immune response, hematopoiesis and cancer.
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Affiliation(s)
- Antoine Dewitte
- INSERM U1026, and Université de Bordeaux, F-33000 Bordeaux, France ; Service d'Anesthésie-Réanimation II, CHU de Bordeaux, F-33600 Pessac, France
| | - Annabelle Tanga
- INSERM U1026, and Université de Bordeaux, F-33000 Bordeaux, France
| | - Julien Villeneuve
- Cell and Developmental Biology Programme, Centre for Genomic Regulation, 08003 Barcelona, Spain ; Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, CA 94720-3200 USA
| | | | - Alexandre Ouattara
- Service d'Anesthésie-Réanimation II, CHU de Bordeaux, F-33600 Pessac, France
| | | | - Christian Combe
- INSERM U1026, and Université de Bordeaux, F-33000 Bordeaux, France ; Service de Néphrologie Transplantation Dialyse, CHU de Bordeaux, F-33076 Bordeaux, France
| | - Jean Ripoche
- INSERM U1026, and Université de Bordeaux, F-33000 Bordeaux, France
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42
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Stolla M, Refaai MA, Heal JM, Spinelli SL, Garraud O, Phipps RP, Blumberg N. Platelet transfusion - the new immunology of an old therapy. Front Immunol 2015; 6:28. [PMID: 25699046 PMCID: PMC4313719 DOI: 10.3389/fimmu.2015.00028] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 01/14/2015] [Indexed: 01/14/2023] Open
Abstract
Platelet transfusion has been a vital therapeutic approach in patients with hematologic malignancies for close to half a century. Randomized trials show that prophylactic platelet transfusions mitigate bleeding in patients with acute myeloid leukemia. However, even with prophylactic transfusions, as many as 75% of patients, experience hemorrhage. While platelet transfusion efficacy is modest, questions and concerns have arisen about the risks of platelet transfusion therapy. The acknowledged serious risks of platelet transfusion include viral transmission, bacterial sepsis, and acute lung injury. Less serious adverse effects include allergic and non-hemolytic febrile reactions. Rare hemolytic reactions have occurred due to a common policy of transfusing without regard to ABO type. In the last decade or so, new concerns have arisen; platelet-derived lipids are implicated in transfusion-related acute lung injury after transfusion. With the recognition that platelets are immune cells came the discoveries that supernatant IL-6, IL-27 sCD40L, and OX40L are closely linked to febrile reactions and sCD40L with acute lung injury. Platelet transfusions are pro-inflammatory, and may be pro-thrombotic. Anti-A and anti-B can bind to incompatible recipient or donor platelets and soluble antigens, impair hemostasis and thus increase bleeding. Finally, stored platelet supernatants contain biological mediators such as VEGF and TGF-β1 that may compromise the host versus tumor response. This is particularly of concern in patients receiving many platelet transfusions, as for acute leukemia. New evidence suggests that removing stored supernatant will improve clinical outcomes. This new view of platelets as pro-inflammatory and immunomodulatory agents suggests that innovative approaches to improving platelet storage and pre-transfusion manipulations to reduce toxicity could substantially improve the efficacy and safety of this long-employed therapy.
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Affiliation(s)
- Moritz Stolla
- Department of Pathology and Laboratory Medicine, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA
| | - Majed A Refaai
- Department of Pathology and Laboratory Medicine, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA
| | - Joanna M Heal
- Department of Pathology and Laboratory Medicine, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA
| | - Sherry L Spinelli
- Department of Pathology and Laboratory Medicine, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA
| | - Olivier Garraud
- Etablissement Francais du Sang Auvergne-Loire, Universite de Lyon , Saint-Etienne , France
| | - Richard P Phipps
- Department of Pathology and Laboratory Medicine, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA ; Department of Microbiology and Immunology, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA ; Department of Environmental Medicine, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA ; Department of Medicine, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA
| | - Neil Blumberg
- Department of Pathology and Laboratory Medicine, School of Medicine and Dentistry, University of Rochester Medical Center , Rochester, NY , USA
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43
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Ali RA, Wuescher LM, Worth RG. Platelets: essential components of the immune system. CURRENT TRENDS IN IMMUNOLOGY 2015; 16:65-78. [PMID: 27818580 PMCID: PMC5096834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Platelets are anucleate cell fragments known for their central role in coagulation and vascular integrity. However, it is becoming increasingly clear that platelets contribute to diverse immunological processes extending beyond the traditional view of platelets as fragmentary mediators of hemostasis and thrombosis. There is recent evidence that platelets participate in: 1) intervention against microbial threats; 2) recruitment and promotion of innate effector cell functions; 3) modulating antigen presentation; and 4) enhancement of adaptive immune responses. In this way, platelets should be viewed as the underappreciated orchestrator of the immune system. This review will discuss recent and historical evidence regarding how platelets influence both innate and adaptive immune responses.
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44
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Ferdous F, Scott T. A comparative examination of thrombocyte/platelet immunity. Immunol Lett 2015; 163:32-9. [DOI: 10.1016/j.imlet.2014.11.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 10/30/2014] [Accepted: 11/12/2014] [Indexed: 10/24/2022]
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45
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Tian J, Zhu T, Liu J, Guo Z, Cao X. Platelets promote allergic asthma through the expression of CD154. Cell Mol Immunol 2014. [PMID: 25418472 DOI: 10.1038/cmi.2014.111.[epubaheadofprint]] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Platelet activation is associated with multiple immune responses and the pathogenesis of various immune-related diseases. However, the exact role and the underlying mechanism of platelets in the progression of allergic asthma remain largely unclear. In this study, we demonstrate that during antigen sensitization, platelets can be activated by ovalbumin (OVA) aerosol via the upregulation of CD154 (CD40L) expression. Platelet transfer promoted allergic asthma progression by inducing more severe leukocyte infiltration and lung inflammation, elevated IgE production and strengthened T helper 2 (Th2) responses in asthma-induced mice. Accordingly, platelet depletion compromised allergic asthma progression. Cd154-deficient platelets failed to promote asthma development, indicating the requirement of CD154 for platelets to promote asthma progression. The mechanistic study showed that platelets inhibited the induction of Foxp3(+) regulatory T cells both in vivo and in vitro at least partially through CD154, providing an explanation for the increase of Th2 responses by platelet transfer. Our study reveals the previously unknown role of platelet CD154 in the promotion of asthma progression by polarizing Th2 responses and inhibiting regulatory T-cell generation and thus provides a potential clue for allergic disease interventions.
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Affiliation(s)
- Jun Tian
- Institute of Immunology, Zhejiang University School of Medicine, Hangzhou, China.,National Key Laboratory of Medical Immunology & Institute of Immunology, Second Military Medical University, Shanghai, China
| | - Tianyi Zhu
- Department of Respiration, General Hospital of Shenyang Military Region, Shenyang, China
| | - Juan Liu
- National Key Laboratory of Medical Immunology & Institute of Immunology, Second Military Medical University, Shanghai, China
| | - Zhenhong Guo
- National Key Laboratory of Medical Immunology & Institute of Immunology, Second Military Medical University, Shanghai, China
| | - Xuetao Cao
- Institute of Immunology, Zhejiang University School of Medicine, Hangzhou, China.,National Key Laboratory of Medical Immunology & Institute of Immunology, Second Military Medical University, Shanghai, China
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46
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Platelets promote allergic asthma through the expression of CD154. Cell Mol Immunol 2014; 12:700-7. [PMID: 25418472 DOI: 10.1038/cmi.2014.111] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 10/12/2014] [Accepted: 10/13/2014] [Indexed: 01/13/2023] Open
Abstract
Platelet activation is associated with multiple immune responses and the pathogenesis of various immune-related diseases. However, the exact role and the underlying mechanism of platelets in the progression of allergic asthma remain largely unclear. In this study, we demonstrate that during antigen sensitization, platelets can be activated by ovalbumin (OVA) aerosol via the upregulation of CD154 (CD40L) expression. Platelet transfer promoted allergic asthma progression by inducing more severe leukocyte infiltration and lung inflammation, elevated IgE production and strengthened T helper 2 (Th2) responses in asthma-induced mice. Accordingly, platelet depletion compromised allergic asthma progression. Cd154-deficient platelets failed to promote asthma development, indicating the requirement of CD154 for platelets to promote asthma progression. The mechanistic study showed that platelets inhibited the induction of Foxp3(+) regulatory T cells both in vivo and in vitro at least partially through CD154, providing an explanation for the increase of Th2 responses by platelet transfer. Our study reveals the previously unknown role of platelet CD154 in the promotion of asthma progression by polarizing Th2 responses and inhibiting regulatory T-cell generation and thus provides a potential clue for allergic disease interventions.
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Andres O, Schulze H, Speer CP. Platelets in neonates: central mediators in haemostasis, antimicrobial defence and inflammation. Thromb Haemost 2014; 113:3-12. [PMID: 25185520 DOI: 10.1160/th14-05-0476] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Accepted: 07/07/2014] [Indexed: 12/26/2022]
Abstract
Platelets are not only centrally involved in haemostasis, but also in antimicrobial defence and inflammation. Since evaluation of platelet physiology in the particular patient group of preterm and term neonatal infants is highly restricted for ethical reasons, there are hardly any data available in healthy and much less in extremely immature or ill neonates. By summarising current knowledge and addressing both platelet researchers and neonatologists, we describe neonatal platelet count and morphology, report on previous analyses of neonatal platelet function in primary haemostasis and provide insights into recent advances in platelet immunology that considerably impacts our clinical view on the critically ill neonatal infant. We conclude that neonatal platelets, originating from liver megakaryocytes, substantially differ from adult platelets and may play a pivotal role in the pathophysiology of neonatal sepsis or intraventricular haemorrhage, both complications which seriously augment perinatal morbidity and mortality.
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Affiliation(s)
- Oliver Andres
- Dr. med. Oliver Andres, University Children's Hospital Würzburg, Josef-Schneider-Straße 2, 97080 Würzburg, Germany, Tel.: +49 931 201 27728, Fax: +49 931 201 6027799, E-mail:
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Abstract
Despite their small size and anucleate status, platelets have diverse roles in vascular biology. Not only are platelets the cellular mediator of thrombosis, but platelets are also immune cells that initiate and accelerate many vascular inflammatory conditions. Platelets are linked to the pathogenesis of inflammatory diseases such as atherosclerosis, malaria infection, transplant rejection, and rheumatoid arthritis. In some contexts, platelet immune functions are protective, whereas in others platelets contribute to adverse inflammatory outcomes. In this review, we will discuss platelet and platelet-derived mediator interactions with the innate and acquired arms of the immune system and platelet-vessel wall interactions that drive inflammatory disease. There have been many recent publications indicating both important protective and adverse roles for platelets in infectious disease. Because of this new accumulating data, and the fact that infectious disease continues to be a leading cause of death globally, we will also focus on new and emerging concepts related to platelet immune and inflammatory functions in the context of infectious disease.
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Aspirin attenuates platelet activation and immune activation in HIV-1-infected subjects on antiretroviral therapy: a pilot study. J Acquir Immune Defic Syndr 2013; 63:280-8. [PMID: 23406976 DOI: 10.1097/qai.0b013e31828a292c] [Citation(s) in RCA: 126] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
BACKGROUND Mechanisms for increased cardiovascular risk in HIV-1-infected adults are incompletely understood, but platelet activation and immune activation leading to a prothrombotic state have been proposed as significant contributors. Aspirin has antiplatelet and immunomodulatory properties. We explored whether 1 week of low-dose aspirin attenuates platelet activation and immune activation in HIV-1-infected and virologically suppressed adults on antiretroviral therapy. METHODS Platelet activation and immune activation were measured in HIV-1-infected subjects virologically suppressed on antiretroviral therapy and controls before and after 1 week of low-dose aspirin. RESULTS Compared with control subjects, HIV-1-infected subjects had increased platelet activation, as measured by spontaneous platelet aggregation and aggregation in response to adenosine diphosphate, collagen, and arachidonic acid. After aspirin therapy, percent aggregation decreased similarly in both HIV-1-infected and control subjects to all platelet agonists tested except aggregation in response to arachidonic acid, which remained elevated in the HIV-1-infected group. HIV-1-infected subjects exhibited increased markers of T-cell activation (CD38 and HLA-DR) and monocyte activation (sCD14), which decreased after 1 week of aspirin therapy. Moreover, leukocyte responses to Toll-like receptor stimulation were enhanced after 1 week of aspirin therapy. In vitro studies showed that HIV-1 plasma could activate healthy platelets, which in turn activated monocytes, implicating a direct role for activated platelets in immune activation. CONCLUSIONS Our data demonstrate that heightened platelet activation and immune activation in treated HIV-1 disease are attenuated by 1 week of aspirin therapy. Aspirin should be further studied for its antithrombotic and immunomodulatory benefits in treated HIV-1 disease.
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