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Effah CY, Ding X, Drokow EK, Li X, Tong R, Sun T. Bacteria-derived extracellular vesicles: endogenous roles, therapeutic potentials and their biomimetics for the treatment and prevention of sepsis. Front Immunol 2024; 15:1296061. [PMID: 38420121 PMCID: PMC10899385 DOI: 10.3389/fimmu.2024.1296061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 01/24/2024] [Indexed: 03/02/2024] Open
Abstract
Sepsis is one of the medical conditions with a high mortality rate and lacks specific treatment despite several years of extensive research. Bacterial extracellular vesicles (bEVs) are emerging as a focal target in the pathophysiology and treatment of sepsis. Extracellular vesicles (EVs) derived from pathogenic microorganisms carry pathogenic factors such as carbohydrates, proteins, lipids, nucleic acids, and virulence factors and are regarded as "long-range weapons" to trigger an inflammatory response. In particular, the small size of bEVs can cross the blood-brain and placental barriers that are difficult for pathogens to cross, deliver pathogenic agents to host cells, activate the host immune system, and possibly accelerate the bacterial infection process and subsequent sepsis. Over the years, research into host-derived EVs has increased, leading to breakthroughs in cancer and sepsis treatments. However, related approaches to the role and use of bacterial-derived EVs are still rare in the treatment of sepsis. Herein, this review looked at the dual nature of bEVs in sepsis by highlighting their inherent functions and emphasizing their therapeutic characteristics and potential. Various biomimetics of bEVs for the treatment and prevention of sepsis have also been reviewed. Finally, the latest progress and various obstacles in the clinical application of bEVs have been highlighted.
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Affiliation(s)
- Clement Yaw Effah
- Department of Critical Care Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Department of Emergency Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Zhengzhou Key Laboratory of Sepsis, Henan Sepsis Diagnosis and Treatment Center, Henan Key Laboratory of Sepsis in Health Commission, Zhengzhou, China
| | - Xianfei Ding
- Department of Critical Care Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Department of Emergency Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Zhengzhou Key Laboratory of Sepsis, Henan Sepsis Diagnosis and Treatment Center, Henan Key Laboratory of Sepsis in Health Commission, Zhengzhou, China
| | - Emmanuel Kwateng Drokow
- Hunan Provincial Key Laboratory of Clinical Epidemiology, Department of Epidemiology and Biostatistics, Xiangya School of Public Health, Central South University, Changsha, Hunan, China
| | - Xiang Li
- Department of Critical Care Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Department of Emergency Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Zhengzhou Key Laboratory of Sepsis, Henan Sepsis Diagnosis and Treatment Center, Henan Key Laboratory of Sepsis in Health Commission, Zhengzhou, China
| | - Ran Tong
- Department of Critical Care Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Department of Emergency Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Zhengzhou Key Laboratory of Sepsis, Henan Sepsis Diagnosis and Treatment Center, Henan Key Laboratory of Sepsis in Health Commission, Zhengzhou, China
| | - Tongwen Sun
- Department of Critical Care Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Department of Emergency Medicine, The First Affiliated Hospital of Zhengzhou University, Henan Engineering Research Center for Critical Care Medicine, Henan Key Laboratory of Critical Care Medicine, Zhengzhou, China
- Zhengzhou Key Laboratory of Sepsis, Henan Sepsis Diagnosis and Treatment Center, Henan Key Laboratory of Sepsis in Health Commission, Zhengzhou, China
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2
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Fang J, Guan H. γ-Secretase inhibitor alleviates lipopolysaccharide-induced myocardial injury through regulating JAK2/STAT3 signaling. ENVIRONMENTAL TOXICOLOGY 2024; 39:135-147. [PMID: 37671635 DOI: 10.1002/tox.23962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 07/17/2023] [Accepted: 08/22/2023] [Indexed: 09/07/2023]
Abstract
BACKGROUND Septic myocardial injury is one of the most life-threatening organ dysfunction. The γ-secretase-based approaches have been developed as potential strategies for diverse diseases management. Unfortunately, the role of γ-secretase inhibitor in septic myocardial injury is unclarified. The present study aims to investigate the effect of γ-secretase inhibitor in septic myocardial injury and reveal its mechanism. METHODS The mouse model of septic myocardial injury was established by intraperitoneally injection of lipopolysaccharide (LPS), and γ-secretase inhibitor MW167 was applied in this model. RNA-sequencing analysis and further bioinformatics analyses were used to screen differential expressed genes (DEGs) and potentially enriched pathways between LPS and LPS + MW167 mice. Pathological examination was performed using haematoxylin and eosin (HE) staining. SD-1029 was used to block JAK2/STAT3 signaling in H9C2 cells and western blot analysis quantified JAK2/STAT3-related proteins. RESULTS LPS induced myocardial injury accompanied with significant inflammatory infiltration and more apoptotic cells. Transcriptome sequencing screened 36 DEGs and bioinformatics identified JAK2/STAT3 signaling pathway was significantly enriched. Further in vitro experiments showed that γ-secretase inhibitor MW167 activated JAK2/STAT3 pathway. Additionally, MW167 restored cell viability, decreased myocardial injury markers including cardiac troponin I (cTnI) and brain natriuretic peptide (BNP), inhibited pro-inflammatory cytokines such as interleukin (IL)-1β and tumor necrosis factor-α (TNF-α) and reduced nitric oxide (NO), cyclooxygenase-2 (COX2) and inducible nitric oxide synthase (iNOS) release. Application of SD-1029 reversely deteriorated LPS-induced myocardial injury and inflammatory response in γ-secretase inhibitor-treated myocardial cells. CONCLUSION The results demonstrate that γ-secretase inhibitor alleviates septic myocardial injury via activating JAK2/STAT3 signaling, and provide novel therapeutic direction for septic myocardial injury.
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Affiliation(s)
- Jingyun Fang
- Department of Emergency, Ganzhou People's Hospital, Ganzhou, China
| | - Huan Guan
- Department of Emergency, Ganzhou People's Hospital, Ganzhou, China
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3
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Ajanel A, Middleton EA. Alterations in the megakaryocyte transcriptome impacts platelet function in sepsis and COVID-19 infection. Thromb Res 2023; 231:247-254. [PMID: 37258336 PMCID: PMC10198739 DOI: 10.1016/j.thromres.2023.05.015] [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: 01/04/2023] [Revised: 04/04/2023] [Accepted: 05/16/2023] [Indexed: 06/02/2023]
Abstract
Platelets and their parent cell, the megakaryocyte (MK), are increasingly recognized for their roles during infection and inflammation. The MK residing in the bone marrow or arising from precursors trafficked to other organs for development go on to form platelets through thrombopoiesis. Infection, by direct and indirect mechanisms, can alter the transcriptional profile of MKs. The altered environment, whether mediated by inflammatory cytokines or other signaling mechanisms results in an altered platelet transcriptome. Platelets released into the circulation, in turn, interact with each other, circulating leukocytes and endothelial cells and contribute to the clearance of pathogens or the potentiation of pathophysiology through such mechanisms as immunothrombosis. In this article we hope to identify key contributions that explore the impact of an altered transcriptomic landscape during severe, systemic response to infection broadly defined as sepsis, and viral infections, including SARS-CoV2. We include current publications that outline the role of MKs from bone-marrow and extra-medullary sites as well as the circulating platelet. The underlying diseases result in thrombotic complications that exacerbate organ dysfunction and mortality. Understanding the impact of platelets on the pathophysiology of disease may drive therapeutic advances to improve the morbidity and mortality of these deadly afflictions.
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Affiliation(s)
- Abigail Ajanel
- Molecular Medicine Program, University of Utah, Salt Lake City, UT 84112, USA; Department of Pathology, University of Utah, Salt Lake City, UT 84112, USA
| | - Elizabeth A Middleton
- Molecular Medicine Program, University of Utah, Salt Lake City, UT 84112, USA; Department of Internal Medicine, University of Utah, Salt Lake City, UT 84112, USA.
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4
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Richardson KC, Jung K, Pardo J, Turner CT, Granville DJ. Noncytotoxic Roles of Granzymes in Health and Disease. Physiology (Bethesda) 2022; 37:323-348. [PMID: 35820180 DOI: 10.1152/physiol.00011.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Granzymes are serine proteases previously believed to play exclusive and somewhat redundant roles in lymphocyte-mediated target cell death. However, recent studies have challenged this paradigm. Distinct substrate profiles and functions have since emerged for each granzyme while their dysregulated proteolytic activities have been linked to diverse pathologies.
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Affiliation(s)
- Katlyn C Richardson
- International Collaboration on Repair Discoveries (ICORD), British Columbia Professional Firefighters' Wound Healing Laboratory, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Karen Jung
- International Collaboration on Repair Discoveries (ICORD), British Columbia Professional Firefighters' Wound Healing Laboratory, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Julian Pardo
- Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Biomedical Research Centre of Aragon (CIBA), Zaragoza, Spain.,Department of Microbiology, Radiology, Pediatrics and Public Health, University of Zaragoza, Zaragoza, Spain.,CIBER de Enfermedades Infecciosas, Instituto de Salud Carlos III, Zaragoza, Spain
| | - Christopher T Turner
- Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia.,Future Industries Institute, University of South Australia, Adelaide, South Australia, Australia
| | - David J Granville
- International Collaboration on Repair Discoveries (ICORD), British Columbia Professional Firefighters' Wound Healing Laboratory, Vancouver Coastal Health Research Institute, Vancouver, British Columbia, Canada.,Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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5
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Dubchak E, Obasanmi G, Zeglinski MR, Granville DJ, Yeung SN, Matsubara JA. Potential role of extracellular granzyme B in wet age-related macular degeneration and fuchs endothelial corneal dystrophy. Front Pharmacol 2022; 13:980742. [PMID: 36204224 PMCID: PMC9531149 DOI: 10.3389/fphar.2022.980742] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 08/16/2022] [Indexed: 11/13/2022] Open
Abstract
Age-related ocular diseases are the leading cause of blindness in developed countries and constitute a sizable socioeconomic burden worldwide. Age-related macular degeneration (AMD) and Fuchs endothelial corneal dystrophy (FECD) are some of the most common age-related diseases of the retina and cornea, respectively. AMD is characterized by a breakdown of the retinal pigment epithelial monolayer, which maintains retinal homeostasis, leading to retinal degeneration, while FECD is characterized by degeneration of the corneal endothelial monolayer, which maintains corneal hydration status, leading to corneal edema. Both AMD and FECD pathogenesis are characterized by disorganized local extracellular matrix (ECM) and toxic protein deposits, with both processes linked to aberrant protease activity. Granzyme B (GrB) is a serine protease traditionally known for immune-mediated initiation of apoptosis; however, it is now recognized that GrB is expressed by a variety of immune and non-immune cells and aberrant extracellular localization of GrB substantially contributes to various age-related pathologies through dysregulated cleavage of ECM, tight junction, and adherens junction proteins. Despite growing recognition of GrB involvement in multiple age-related pathologies, its role in AMD and FECD remains poorly understood. This review summarizes the pathophysiology of, and similarities between AMD and FECD, outlines the current knowledge of the role of GrB in AMD and FECD, as well as hypothesizes putative contributions of GrB to AMD and FECD pathogenesis and highlights the therapeutic potential of pharmacologically inhibiting GrB as an adjunctive treatment for AMD and FECD.
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Affiliation(s)
- Eden Dubchak
- Department of Ophthalmology and Visual Sciences, University of British Columbia (UBC), Vancouver, BC, Canada
| | - Gideon Obasanmi
- Department of Ophthalmology and Visual Sciences, University of British Columbia (UBC), Vancouver, BC, Canada
| | - Matthew R. Zeglinski
- ICORD Centre and Department of Pathology and Laboratory Medicine, Vancouver Coastal Health Research Institute, UBC, Vancouver, BC, Canada
| | - David J. Granville
- ICORD Centre and Department of Pathology and Laboratory Medicine, Vancouver Coastal Health Research Institute, UBC, Vancouver, BC, Canada
| | - Sonia N. Yeung
- Department of Ophthalmology and Visual Sciences, University of British Columbia (UBC), Vancouver, BC, Canada
| | - Joanne A. Matsubara
- Department of Ophthalmology and Visual Sciences, University of British Columbia (UBC), Vancouver, BC, Canada
- *Correspondence: Joanne A. Matsubara,
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Zhang Y, Chen W, Cheng X, Wang F, Gao C, Song F, Song F, Liang X, Fang W, Chen Z. Sphingomyelin Phodiesterase Acid-Like 3A Promotes Hepatocellular Carcinoma Growth Through the Enhancer of Rudimentary Homolog. Front Oncol 2022; 12:852765. [PMID: 35686107 PMCID: PMC9171240 DOI: 10.3389/fonc.2022.852765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Accepted: 04/25/2022] [Indexed: 12/24/2022] Open
Abstract
Background Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide, with unclear pathogenesis. Sphingomyelin phodiesterase acid-like 3A (SMPDL3A) affects cell differentiation and participates in immune regulation. However, its molecular biological function in HCC has not yet been elucidated. Methods Data from 180 HCC patients were analyzed the relationship between the expression of SMPDL3A in liver cancer tissues and the prognosis of liver cancer patients. Crispr-Cas9 dual vector lentivirus was used to knock out SMPDL3A in HCC cell lines. The effects of SMPDL3A on cell viability were determined by CCK8 assay, clone formation experiment, cell cycle assay, cell scratch, TUNEL experiment and flow cytometry. Xenograft tumor assays in BALB/c nude mice confirmed that SMPDL3A promoted tumor growth and in vivo. Preliminary exploration of SMPDL3A interacting protein by mass spectrometry analysis and co-immunoprecipitation. Results This study showed that the expression of SMPDL3A in HCC tissue differed from that in tumor-adjacent tissues. Moreover, the overall survival rate and tumor-free survival rate of patients with high-SMPDL3A expression were significantly lower than those with low-SMPDL3A expression. SMPDL3A expression was closely related to the level of protein induced by PIVKA-II, liver cirrhosis, tumor diameter, microvascular invasion, and Barcelona clinic liver cancer staging. Thus, SMPDL3A is an independent risk factor that affects the tumor-free survival rate and overall survival rate of HCC patients. In vitro study using Crispr-Cas9 genome editing technology revealed the knockout effect of SMPDL3A on cell proliferation, apoptosis, and migration. Cell counting kit-8 assay and clone formation experiment showed that sgSMPDL3A inhibited tumor cell proliferation and migration. Flow cytometry and TUNEL assay showed that sgSMPDL3A promoted apoptosis in tumors. Moreover, sgSMPDL3A inhibited tumor growth during subcutaneous tumor formation in nude mice. Immunohistochemistry of Ki67 and PNCA also indicated that sgSMPDL3A inhibited subcutaneous tumor proliferation in tumor-bearing nude mice. Further experiments showed that SMPDL3A interacts with the enhancer of rudimentary homolog (ERH). Conclusions High-SMPDL3A expression was related to poor prognosis of patients with HCC. Knockout of SMPDL3A inhibited the proliferation and migration and accelerated the migration of HCC cells. SMPDL3A interacted with ERH to affect the tumorigenesis and progression of HCC.
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Affiliation(s)
- Yu Zhang
- Department of Hepatobiliary Surgery, Affiliated Hospital of Nantong University, Nantong, China.,School of Medicine, Nantong University, Nantong, China
| | - Weipeng Chen
- School of Medicine, Nantong University, Nantong, China.,Department of General Surgery, Binhai County People's Hospital, Yancheng, China
| | - Xin Cheng
- School of Medicine, Nantong University, Nantong, China.,Department of General Surgery, Jingjiang People's Hospital, Taizhou, China
| | - Feiran Wang
- Department of Hepatobiliary Surgery, Affiliated Hospital of Nantong University, Nantong, China.,School of Medicine, Nantong University, Nantong, China
| | - Cheng Gao
- Department of Hepatobiliary Surgery, Affiliated Hospital of Nantong University, Nantong, China.,School of Medicine, Nantong University, Nantong, China
| | - Fei Song
- Department of Hepatobiliary Surgery, Affiliated Hospital of Nantong University, Nantong, China
| | - Fengliang Song
- Department of Hepatobiliary Surgery, Affiliated Hospital of Nantong University, Nantong, China
| | - Xiaoliang Liang
- Department of Hepatobiliary Surgery, Affiliated Hospital of Nantong University, Nantong, China
| | - Wanzhi Fang
- Department of Hepatobiliary Surgery, Affiliated Hospital of Nantong University, Nantong, China
| | - Zhong Chen
- Department of Hepatobiliary Surgery, Affiliated Hospital of Nantong University, Nantong, China
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7
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Platelet number and function alterations in preclinical models of sterile inflammation and sepsis patients: implications in the pathophysiology and treatment of inflammation. Transfus Apher Sci 2022; 61:103413. [DOI: 10.1016/j.transci.2022.103413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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8
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Zhong H, Waresi M, Zhang W, Han L, Zhao Y, Chen Y, Zhou P, Chang L, Pan G, Wu B, Li J, Zhang S, Shi H, Luo X, Gao W, Qi Z, Ding Z. NOD2-mediated P2Y 12 upregulation increases platelet activation and thrombosis in sepsis. Biochem Pharmacol 2021; 194:114822. [PMID: 34748820 DOI: 10.1016/j.bcp.2021.114822] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/14/2021] [Accepted: 11/02/2021] [Indexed: 11/18/2022]
Abstract
BACKGROUND Platelets from septic patients exhibit increased reactivity. However, the underlying mechanism of sepsis-induced platelet hyperactivity is still not completely understood. OBJECTIVE P2Y12 is a central receptor for platelet activation. In this study, we investigated the role of platelet P2Y12 in platelet hyperactivity during sepsis. METHODS We measured platelet P2Y12 expression and aggregation in response to ADP in septic patients and cecal ligation and puncture (CLP)-treated mice. We also detected the downstream signaling of P2Y12 in resting platelets from patients and mice with sepsis. The role of nucleotide-binding oligomerization domain 2 (NOD2)/RIP2/NF-κB/P65 pathway in sepsis-induced platelet P2Y12 high expression was also investigated. Finally, we compared the antiplatelet and antithrombotic effects of clopidogrel, prasugrel, and ticagrelor in experimental sepsis in mice and rats. RESULTS Compared to healthy subjects, platelets from septic patients exhibit P2Y12 hyperactivity and higher P2Y12 expression. pAkt is enhanced and pVASP is impaired in resting platelets from the patients, indicating the constitutive activation of platelet P2Y12 receptor. Mouse sepsis model recapitulates the findings in septic patients. NOD2 deficiency attenuates sepsis-induced platelet P2Y12 high expression, hyperactivity, and thrombosis. Prasugrel and ticagrelor are potent P2Y12 inverse agonists, and exhibit superior antiplatelet and antithrombotic efficacy over clopidogrel in mice and rats with sepsis. CONCLUSIONS NOD2 activation upregulates platelet P2Y12 expression, which is constitutively activated and contributes to platelet hyperactivity in septic status. Compared to clopidogrel, prasugrel and ticagrelor are potent P2Y12 inverse agonists with superior antiplatelet and antithrombotic efficacy in experimental sepsis.
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Affiliation(s)
- Haoxuan Zhong
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Maieryemu Waresi
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Wei Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Liping Han
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Yikai Zhao
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Yufei Chen
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Peng Zhou
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Lin Chang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Guanxing Pan
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Bangwei Wu
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Jian Li
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Si Zhang
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China
| | - Haiming Shi
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Xinping Luo
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China
| | - Wen Gao
- Department of Cardiology, Huashan Hospital, Fudan University. Shanghai, China.
| | - Zhiyong Qi
- Department of Cardiology, Zhongshan Hospital, Fudan University, Shanghai Institute of Cardiovascular Diseases, Shanghai, China.
| | - Zhongren Ding
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Fudan University, Shanghai, China; School of Pharmacy, Tianjin Medical University, Tianjin, China.
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9
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Rolfes V, Ribeiro LS, Hawwari I, Böttcher L, Rosero N, Maasewerd S, Santos MLS, Próchnicki T, Silva CMDS, Wanderley CWDS, Rothe M, Schmidt SV, Stunden HJ, Bertheloot D, Rivas MN, Fontes CJ, Carvalho LH, Cunha FQ, Latz E, Arditi M, Franklin BS. Platelets Fuel the Inflammasome Activation of Innate Immune Cells. Cell Rep 2021; 31:107615. [PMID: 32402278 PMCID: PMC7225754 DOI: 10.1016/j.celrep.2020.107615] [Citation(s) in RCA: 80] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 03/12/2020] [Accepted: 04/14/2020] [Indexed: 12/12/2022] Open
Abstract
The inflammasomes control the bioactivity of pro-inflammatory cytokines of the interleukin (IL)-1 family. The inflammasome assembled by NLRP3 has been predominantly studied in homogeneous cell populations in vitro, neglecting the influence of cellular interactions that occur in vivo. Here, we show that platelets boost the inflammasome capacity of human macrophages and neutrophils and are critical for IL-1 production by monocytes. Platelets license NLRP3 transcription, thereby enhancing ASC oligomerization, caspase-1 activity, and IL-1β secretion. Platelets influence IL-1β production in vivo, and blood platelet counts correlate with plasmatic IL-1β levels in malaria. Furthermore, we reveal an enriched platelet gene signature among the highest-expressed transcripts in IL-1β-driven autoinflammatory diseases. The platelet effect is independent of cell-to-cell contact, platelet-derived lipid mediators, purines, nucleic acids, and a host of platelet cytokines, and it involves the triggering of calcium-sensing receptors on macrophages. Hence, platelets provide an additional layer of regulation of inflammasomes and IL-1-driven inflammation. Platelets license NLRP3 for inflammasome activattion in innate immune cells Platelets are required for optimal monocyte inflammasome activation Platelets shape IL-1β in vivo, and platelet counts correlate with IL-1β in plasma A constitutive, heat-sensitive soluble platelet-factor boost IL-1β in macrophages
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Affiliation(s)
- Verena Rolfes
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Lucas Secchim Ribeiro
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany.
| | - Ibrahim Hawwari
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Lisa Böttcher
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Nathalia Rosero
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Salie Maasewerd
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Marina Lima Silva Santos
- Laboratório de Malária, Instituto René Rachou, Fundação Oswaldo Cruz, 30190-002 Belo Horizonte, MG, Brazil
| | - Tomasz Próchnicki
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Camila Meirelles de Souza Silva
- Center for Research in Inflammatory Diseases, School of Medicine of Ribeirão Preto, University of Sao Paulo, 14049-900 Ribeirão Preto, SP, Brazil
| | - Carlos Wagner de Souza Wanderley
- Center for Research in Inflammatory Diseases, School of Medicine of Ribeirão Preto, University of Sao Paulo, 14049-900 Ribeirão Preto, SP, Brazil
| | - Maximilian Rothe
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Susanne V Schmidt
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - H James Stunden
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Damien Bertheloot
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany
| | - Magali Noval Rivas
- Departments of Pediatrics, Division of Infectious Diseases and Immunology, and Infectious and Immunologic Diseases Research Center (IIDRC), Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA
| | - Cor Jesus Fontes
- Departamento de Clínica Médica, Universidade Federal de Mato Grosso, 78060-900 Cuiabá, MT, Brazil
| | - Luzia Helena Carvalho
- Laboratório de Malária, Instituto René Rachou, Fundação Oswaldo Cruz, 30190-002 Belo Horizonte, MG, Brazil
| | - Fernando Queiroz Cunha
- Center for Research in Inflammatory Diseases, School of Medicine of Ribeirão Preto, University of Sao Paulo, 14049-900 Ribeirão Preto, SP, Brazil
| | - Eicke Latz
- Institute of Innate Immunity, Medical Faculty, University of Bonn, 53127 Bonn, NRW, Germany; Department of Infectious Diseases and Immunology, University of Massachusetts Medical School, Worcester, MA 01655, USA; German Center for Neurodegenerative Diseases, 53127 Bonn, NRW, Germany
| | - Moshe Arditi
- Departments of Pediatrics, Division of Infectious Diseases and Immunology, and Infectious and Immunologic Diseases Research Center (IIDRC), Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA.
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10
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Gutmann C, Joshi A, Zampetaki A, Mayr M. The Landscape of Coding and Noncoding RNAs in Platelets. Antioxid Redox Signal 2021; 34:1200-1216. [PMID: 32460515 DOI: 10.1089/ars.2020.8139] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Significance: Levels of platelet noncoding RNAs (ncRNAs) are altered by disease, and ncRNAs may exert functions inside and outside of platelets. Their role in physiologic hemostasis and pathologic thrombosis remains to be explored. Recent Advances: The number of RNA classes identified in platelets has been growing since the past decade. Apart from coding messenger RNAs, the RNA landscape in platelets comprises ncRNAs such as microRNAs, circular RNAs, long ncRNAs, YRNAs, and potentially environmentally derived exogenous ncRNAs. Recent research has focused on the function of platelet RNAs beyond platelets, mediated through protective RNA shuttles or even cellular uptake of entire platelets. Multiple studies have also explored the potential of platelet RNAs as novel biomarkers. Critical Issues: Platelet preparations can contain contaminating leukocytes. Even few leukocytes may contribute a substantial amount of RNA. As biomarkers, platelet RNAs have shown associations with platelet activation, but it remains to be seen whether their measurements could improve diagnostics. It also needs to be clarified whether platelet RNAs influence processes beyond platelets. Future Directions: Technological advances such as single-cell RNA-sequencing might help to identify hyperreactive platelet subpopulations on a single-platelet level, avoid the common problem of leukocyte contamination in platelet preparations, and allow simultaneous profiling of native megakaryocytes and their platelet progeny to clarify to what extent the platelet RNA content reflects their megakaryocyte precursors or changes in the circulation. Antioxid. Redox Signal. 34, 1200-1216.
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Affiliation(s)
- Clemens Gutmann
- King's British Heart Foundation Centre, King's College London, London, United Kingdom
| | - Abhishek Joshi
- King's British Heart Foundation Centre, King's College London, London, United Kingdom
| | - Anna Zampetaki
- King's British Heart Foundation Centre, King's College London, London, United Kingdom
| | - Manuel Mayr
- King's British Heart Foundation Centre, King's College London, London, United Kingdom
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11
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Eustes AS, Campbell RA, Middleton EA, Tolley ND, Manne BK, Montenont E, Rowley JW, Krauel K, Blair A, Guo L, Kosaka Y, Medeiros-de-Moraes IM, Lacerda M, Hottz ED, Neto HCF, Zimmerman GA, Weyrich AS, Petrey A, Rondina MT. Heparanase expression and activity are increased in platelets during clinical sepsis. J Thromb Haemost 2021; 19:1319-1330. [PMID: 33587773 PMCID: PMC8218538 DOI: 10.1111/jth.15266] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 01/22/2021] [Accepted: 02/08/2021] [Indexed: 12/17/2022]
Abstract
BACKGROUND Heparanase (HPSE) is the only known mammalian enzyme that can degrade heparan sulfate. Heparan sulfate proteoglycans are essential components of the glycocalyx, and maintain physiological barriers between the blood and endothelial cells. HPSE increases during sepsis, which contributes to injurious glyocalyx degradation, loss of endothelial barrier function, and mortality. OBJECTIVES As platelets are one of the most abundant cellular sources of HPSE, we sought to determine whether HPSE expression and activity increases in human platelets during clinical sepsis. We also examined associations between platelet HPSE expression and clinical outcomes. PATIENTS/METHODS Expression and activity of HPSE was determined in platelets isolated from septic patients (n = 59) and, for comparison, sex-matched healthy donors (n = 46) using complementary transcriptomic, proteomic, and functional enzymatic assays. Septic patients were followed for the primary outcome of mortality, and clinical data were captured prospectively for septic patients. RESULTS The mRNA expression of HPSE was significantly increased in platelets isolated from septic patients. Ribosomal footprint profiling, followed by [S35] methionine labeling assays, demonstrated that HPSE mRNA translation and HPSE protein synthesis were significantly upregulated in platelets during sepsis. While both the pro- and active forms of HPSE protein increased in platelets during sepsis, only the active form of HPSE protein significantly correlated with sepsis-associated mortality. Consistent with transcriptomic and proteomic upregulation, HPSE enzymatic activity was also increased in platelets during sepsis. CONCLUSIONS During clinical sepsis HPSE, translation, and enzymatic activity are increased in platelets. Increased expression of the active form of HPSE protein is associated with sepsis-associated mortality.
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Affiliation(s)
- Alicia S Eustes
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
- Hospitals and Clinics Pathology, Internal Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Robert A Campbell
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Elizabeth A Middleton
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Neal D Tolley
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Bhanu K Manne
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Emilie Montenont
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Jesse W Rowley
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Krystin Krauel
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
- Department of Cardiology and Angiology I, Heart Center, University of Freiburg, Freiburg, Germany
| | - Antoinette Blair
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Li Guo
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Yasuhiro Kosaka
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Isabel M Medeiros-de-Moraes
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (Fiocruz, Rio de Janeiro and Manaus, Brazil
| | - Marcus Lacerda
- Fundacao de Medicina Tropical - Dr. Heitor Vieira Dourado (FMT-HVD) and Fiocruz Manaus, Manaus, Brazil
| | - Eugenio D Hottz
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (Fiocruz, Rio de Janeiro and Manaus, Brazil
- Immunothrombosis Laboratory, Department of Biochemistry, Federal University of Juiz de Fora, Juiz de Fora, Brazil
- Instituto Nacional de Infectologia Evandro Chagas, Rio de Janeiro, Brazil
| | - Hugo Castro Faria Neto
- Fundacao de Medicina Tropical - Dr. Heitor Vieira Dourado (FMT-HVD) and Fiocruz Manaus, Manaus, Brazil
| | - Guy A Zimmerman
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
| | - Andrew S Weyrich
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
| | - Aaron Petrey
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
| | - Matthew T Rondina
- Department of Internal Medicine and Molecular Medicine Program, University of Utah, Salt Lake City, Utah, USA
- Department of Pathology, University of Utah, Salt Lake City, Utah, USA
- Department of Internal Medicine and GRECC, George E. Wahlen VAMC, Salt Lake City, Utah, USA
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12
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Wang W, Zou R, Qiu Y, Liu J, Xin Y, He T, Qiu Z. Interaction Networks Converging on Immunosuppressive Roles of Granzyme B: Special Niches Within the Tumor Microenvironment. Front Immunol 2021; 12:670324. [PMID: 33868318 PMCID: PMC8047302 DOI: 10.3389/fimmu.2021.670324] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 03/15/2021] [Indexed: 12/12/2022] Open
Abstract
Granzyme B is a renowned effector molecule primarily utilized by CTLs and NK cells against ill-defined and/or transformed cells during immunosurveillance. The overall expression of granzyme B within tumor microenvironment has been well-established as a prognostic marker indicative of priming immunity for a long time. Until recent years, increasing immunosuppressive effects of granzyme B are unveiled in the setting of different immunological context. The accumulative evidence confounded the roles of granzyme B in immune responses, thereby arousing great interests in characterizing detailed feature of granzyme B-positive niche. In this paper, the granzyme B-related regulatory effects of major suppressor cells as well as the tumor microenvironment that defines such functionalities were longitudinally summarized and discussed. Multiplex networks were built upon the interactions among different transcriptional factors, cytokines, and chemokines that regarded to the initiation and regulation of granzyme B-mediated immunosuppression. The conclusions and prospect may facilitate better interpretations of the clinical significance of granzyme B, guiding the rational development of therapeutic regimen and diagnostic probes for anti-tumor purposes.
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Affiliation(s)
- Weinan Wang
- School of Pharmaceutical Sciences, Changchun University of Chinese Medicine, Changchun, China
| | - Rui Zou
- School of Pharmaceutical Sciences, Changchun University of Chinese Medicine, Changchun, China
| | - Ye Qiu
- School of Pharmaceutical Sciences, Changchun University of Chinese Medicine, Changchun, China
| | - Jishuang Liu
- School of Pharmaceutical Sciences, Changchun University of Chinese Medicine, Changchun, China
| | - Yu Xin
- School of Pharmaceutical Sciences, Changchun University of Chinese Medicine, Changchun, China
| | - Tianzhu He
- School of Pharmaceutical Sciences, Changchun University of Chinese Medicine, Changchun, China.,School of Basic Medical Sciences, Changchun University of Chinese Medicine, Changchun, China
| | - Zhidong Qiu
- School of Pharmaceutical Sciences, Changchun University of Chinese Medicine, Changchun, China
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13
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Hagn M, Jahrsdörfer B. Why do human B cells secrete granzyme B? Insights into a novel B-cell differentiation pathway. Oncoimmunology 2021; 1:1368-1375. [PMID: 23243600 PMCID: PMC3518509 DOI: 10.4161/onci.22354] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
B cells are generally believed to operate as producers of high affinity antibodies to defend the body against microorganisms, whereas cellular cytotoxicity is considered as an exclusive prerogative of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). In conflict with this dogma, recent studies have demonstrated that the combination of interleukin-21 (IL-21) and B-cell receptor (BCR) stimulation enables B cells to produce and secrete the active form of the cytotoxic serine protease granzyme B (GrB). Although the production of GrB by B cells is not accompanied by that of perforin as in the case of many other GrB-secreting cells, recent findings suggest GrB secretion by B cells may play a significant role in early antiviral immune responses, in the regulation of autoimmune responses, and in cancer immunosurveillance. Here, we discuss in detail how GrB-secreting B cells may influence a variety of immune processes. A better understanding of the role that GrB-secreting B cells are playing in the immune system may allow for the development and improvement of novel immunotherapeutic approaches against infectious, autoimmune and malignant diseases.
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Affiliation(s)
- Magdalena Hagn
- Cancer Immunology Program; Peter MacCallum Cancer Centre; Melbourne, Australia
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14
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Yeung AK, Villacorta-Martin C, Hon S, Rock JR, Murphy GJ. Lung megakaryocytes display distinct transcriptional and phenotypic properties. Blood Adv 2020; 4:6204-6217. [PMID: 33351116 PMCID: PMC7757004 DOI: 10.1182/bloodadvances.2020002843] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 11/18/2020] [Indexed: 12/11/2022] Open
Abstract
Megakaryocytes (MKs) are responsible for platelet biogenesis, which is believed to occur canonically in adult bone marrow (BM) and in the fetal liver during development. However, emerging evidence highlights the lung as a previously underappreciated residence for MKs that may contribute significantly to circulating platelet mass. Although a diversity of cells specific to the BM is known to promote the maturation and trafficking of MKs, little investigation into the impact of the lung niche on the development and function of MKs has been done. Here, we describe the application of single-cell RNA sequencing, coupled with histological, ploidy, and flow cytometric analyses, to profile primary MKs derived from syngeneic mouse lung and hematopoietic tissues. Transcriptional profiling demonstrated that lung MKs have a unique signature distinct from their hematopoietic counterparts, with lung MKs displaying enrichment for maturation markers, potentially indicating a propensity for more efficient platelet production. Reciprocally, fetal lung MKs also showed the robust expression of cytokines and growth factors that are known to promote lung development. Lastly, lung MKs possess an enrichment profile skewed toward roles in immunity and inflammation. These findings highlight the existence of a lung-specific MK phenotype and support the notion that the lung plays an independent role in the development and functional maturation of MKs. The immune phenotype displayed by lung MKs also introduces their potential role in microbial surveillance and antigen presentation.
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Affiliation(s)
- Anthony K Yeung
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA; and
- Section of Hematology and Medical Oncology and
| | - Carlos Villacorta-Martin
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA; and
| | - Stephanie Hon
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA; and
- Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA
| | - Jason R Rock
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA; and
- Pulmonary Center and Department of Medicine, Boston University School of Medicine, Boston, MA
| | - George J Murphy
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA; and
- Section of Hematology and Medical Oncology and
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15
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Melki I, Allaeys I, Tessandier N, Mailhot B, Cloutier N, Campbell RA, Rowley JW, Salem D, Zufferey A, Laroche A, Lévesque T, Patey N, Rauch J, Lood C, Droit A, McKenzie SE, Machlus KR, Rondina MT, Lacroix S, Fortin PR, Boilard E. FcγRIIA expression accelerates nephritis and increases platelet activation in systemic lupus erythematosus. Blood 2020; 136:2933-2945. [PMID: 33331924 PMCID: PMC7751357 DOI: 10.1182/blood.2020004974] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 07/11/2020] [Indexed: 02/06/2023] Open
Abstract
Systemic lupus erythematosus (SLE) is an autoimmune inflammatory disease characterized by deposits of immune complexes (ICs) in organs and tissues. The expression of FcγRIIA by human platelets, which is their unique receptor for immunoglobulin G antibodies, positions them to ideally respond to circulating ICs. Whereas chronic platelet activation and thrombosis are well-recognized features of human SLE, the exact mechanisms underlying platelet activation in SLE remain unknown. Here, we evaluated the involvement of FcγRIIA in the course of SLE and platelet activation. In patients with SLE, levels of ICs are associated with platelet activation. Because FcγRIIA is absent in mice, and murine platelets do not respond to ICs in any existing mouse model of SLE, we introduced the FcγRIIA (FCGR2A) transgene into the NZB/NZWF1 mouse model of SLE. In mice, FcγRIIA expression by bone marrow cells severely aggravated lupus nephritis and accelerated death. Lupus onset initiated major changes to the platelet transcriptome, both in FcγRIIA-expressing and nonexpressing mice, but enrichment for type I interferon response gene changes was specifically observed in the FcγRIIA mice. Moreover, circulating platelets were degranulated and were found to interact with neutrophils in FcγRIIA-expressing lupus mice. FcγRIIA expression in lupus mice also led to thrombosis in lungs and kidneys. The model recapitulates hallmarks of human SLE and can be used to identify contributions of different cellular lineages in the manifestations of SLE. The study further reveals a role for FcγRIIA in nephritis and in platelet activation in SLE.
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Affiliation(s)
- Imene Melki
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Isabelle Allaeys
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Nicolas Tessandier
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Benoit Mailhot
- Département de Médecine Moléculaire, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
- Axe Neurosciences, Université Laval, Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
| | - Nathalie Cloutier
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Robert A Campbell
- Department of Internal Medicine and Pathology, University of Utah, Salt Lake City, UT
- University of Utah Molecular Medicine Program, Eccles Institute of Human Genetics, Salt Lake City, UT
| | - Jesse W Rowley
- Department of Internal Medicine and Pathology, University of Utah, Salt Lake City, UT
- University of Utah Molecular Medicine Program, Eccles Institute of Human Genetics, Salt Lake City, UT
| | - David Salem
- Division of Rheumatology, Department of Medicine, McGill University, Montreal, QC, Canada
- Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Anne Zufferey
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Audrée Laroche
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Tania Lévesque
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Natalie Patey
- Centre Hospitalier Universitaire de Sainte-Justine, Département de Pathologie et Biologie Cellulaire, Faculté de Médecine, Université de Montreal, Montreal, QC, Canada
| | - Joyce Rauch
- Division of Rheumatology, Department of Medicine, McGill University, Montreal, QC, Canada
- Research Institute of the McGill University Health Centre, Montreal, QC, Canada
| | - Christian Lood
- Division of Rheumatology, Department of Medicine, University of Washington, Seattle, WA
| | - Arnaud Droit
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Département de Médecine Moléculaire, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Steven E McKenzie
- Cardeza Foundation for Hematological Research, Thomas Jefferson University, Philadelphia, PA
| | - Kellie R Machlus
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA; and
| | - Matthew T Rondina
- Axe Neurosciences, Université Laval, Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- University of Utah Molecular Medicine Program, Eccles Institute of Human Genetics, Salt Lake City, UT
- Department of Internal Medicine-Geriatric Research Education and Clinical Center (GRECC), George E. Wahlen Veterans Affairs Medical Center (VAMC), Salt Lake City, UT
| | - Steve Lacroix
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
- Département de Médecine Moléculaire, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Paul R Fortin
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
| | - Eric Boilard
- Centre de Recherche du Centre Hospitalier Universitaire de Québec-Université Laval, Québec, QC, Canada
- Centre de Recherche Arthrite, Faculté de Médecine de l'Université Laval, Québec, QC, Canada
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16
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Garzón-Tituaña M, Arias MA, Sierra-Monzón JL, Morte-Romea E, Santiago L, Ramirez-Labrada A, Martinez-Lostao L, Paño-Pardo JR, Galvez EM, Pardo J. The Multifaceted Function of Granzymes in Sepsis: Some Facts and a Lot to Discover. Front Immunol 2020; 11:1054. [PMID: 32655547 PMCID: PMC7325996 DOI: 10.3389/fimmu.2020.01054] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 04/30/2020] [Indexed: 12/21/2022] Open
Abstract
Sepsis is a serious global health problem. In addition to a high incidence, this syndrome has a high mortality and is responsible for huge health expenditure. The pathophysiology of sepsis is very complex and it is not well-understood yet. However, it is widely accepted that the initial phase of sepsis is characterized by a hyperinflammatory response while the late phase is characterized by immunosuppression and immune anergy, increasing the risk of secondary infections. Granzymes (Gzms) are a family of serine proteases classified according to their cleavage specificity. Traditionally, it was assumed that all Gzms acted as cytotoxic proteases. However, recent evidence suggests that GzmB is the one with the greatest cytotoxic capacity, while the cytotoxicity of others such as GzmA and GzmK is not clear. Recent studies have found that GzmA, GzmB, GzmK, and GzmM act as pro-inflammatory mediators. Specially, solid evidences show that GzmA and GzmK function as extracellular proteases that regulate the inflammatory response irrespectively of its ability to induce cell death. Indeed, studies in animal models indicate that GzmA is involved in the cytokine release syndrome characteristic of sepsis. Moreover, the GZM family also could regulate other biological processes involved in sepsis pathophysiology like the coagulation cascade, platelet function, endothelial barrier permeability, and, in addition, could be involved in the immunosuppressive stage of sepsis. In this review, we provide a comprehensive overview on the contribution of these novel functions of Gzms to sepsis and the new therapeutic opportunities emerging from targeting these proteases for the treatment of this serious health problem.
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Affiliation(s)
- Marcela Garzón-Tituaña
- Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain
| | | | - José L Sierra-Monzón
- Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain.,Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain
| | - Elena Morte-Romea
- Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain.,Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain
| | - Llipsy Santiago
- Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain
| | - Ariel Ramirez-Labrada
- Nanotoxicology and Immunotoxicology Unit (UNATI), Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Zaragoza, Spain
| | - Luis Martinez-Lostao
- Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain.,Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain.,Nanoscience Institute of Aragon (INA), University of Zaragoza, Zaragoza, Spain
| | - José R Paño-Pardo
- Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain.,Hospital Clínico Universitario Lozano Blesa, Zaragoza, Spain
| | - Eva M Galvez
- Instituto de Carboquímica ICB-CSIC, Zaragoza, Spain
| | - Julián Pardo
- Fundación Instituto de Investigación Sanitaria Aragón (IIS Aragón), Biomedical Research Centre of Aragón (CIBA), Zaragoza, Spain.,Nanoscience Institute of Aragon (INA), University of Zaragoza, Zaragoza, Spain.,Aragon I + D Foundation (ARAID), Zaragoza, Spain.,Department of Biochemistry and Molecular and Cell Biology and Department of Microbiology, Preventive Medicine and Public Health, University of Zaragoza, Zaragoza, Spain.,Centro de Investigación Biomédica en Red de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Madrid, Spain
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17
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Davizon-Castillo P, Rowley JW, Rondina MT. Megakaryocyte and Platelet Transcriptomics for Discoveries in Human Health and Disease. Arterioscler Thromb Vasc Biol 2020; 40:1432-1440. [PMID: 32295424 PMCID: PMC7253186 DOI: 10.1161/atvbaha.119.313280] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Anucleate platelets, long viewed as merely cell fragments with a limited repertoire of rapid-acting hemostatic functions, are now recognized to have a complex and dynamic transcriptome mirroring that of many nucleated cells. The field of megakaryocyte and platelet transcriptomics has been rapidly growing, particularly with the advent of newer technologies such as next-generation RNA-sequencing. Studies interrogating the megakaryocyte and platelet transcriptome have led to a number of key insights into human health and disease. In this brief focused review, we will discuss some of the recent discoveries made through transcriptome analysis of megakaryocytes and platelets. We will also highlight the utility of integrating ribosome footprint analysis to augment discoveries. Both bulk and single-cell sequencing approaches will be reviewed, along with comparative studies between human and murine platelets under basal healthy settings and during acute systemic inflammatory diseases.
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Affiliation(s)
- Pavel Davizon-Castillo
- From the Section of Pediatric Hematology, Oncology, and Bone Marrow Transplant, University of Colorado, Aurora (P.D.-C)
| | - Jesse W Rowley
- University of Utah Molecular Medicine Program, University of Utah, Salt Lake City (J.W.R., M.T.R.).,Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City (J.W.R., M.T.R.)
| | - Matthew T Rondina
- From the Section of Pediatric Hematology, Oncology, and Bone Marrow Transplant, University of Colorado, Aurora (P.D.-C).,University of Utah Molecular Medicine Program, University of Utah, Salt Lake City (J.W.R., M.T.R.).,Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City (J.W.R., M.T.R.).,Department of Pathology, University of Utah, Salt Lake City (M.T.R.).,George E. Wahlen VAMC, Salt Lake City, UT (M.T.R.)
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18
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Reduced miR-26b Expression in Megakaryocytes and Platelets Contributes to Elevated Level of Platelet Activation Status in Sepsis. Int J Mol Sci 2020; 21:ijms21030866. [PMID: 32013235 PMCID: PMC7036890 DOI: 10.3390/ijms21030866] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/22/2020] [Accepted: 01/26/2020] [Indexed: 12/16/2022] Open
Abstract
In sepsis, platelets may become activated via toll-like receptors (TLRs), causing microvascular thrombosis. Megakaryocytes (MKs) also express these receptors; thus, severe infection may modulate thrombopoiesis. To explore the relevance of altered miRNAs in platelet activation upon sepsis, we first investigated sepsis-induced miRNA expression in platelets of septic patients. The effect of abnormal Dicer level on miRNA expression was also evaluated. miRNAs were profiled in septic vs. normal platelets using TaqMan Open Array. We validated platelet miR-26b with its target SELP (P-selectin) mRNA levels and correlated them with clinical outcomes. The impact of sepsis on MK transcriptome was analyzed in MEG-01 cells after lipopolysaccharide (LPS) treatment by RNA-seq. Sepsis-reduced miR-26b was further studied using Dicer1 siRNA and calpain inhibition in MEG-01 cells. Out of 390 platelet miRNAs detected, there were 121 significantly decreased, and 61 upregulated in sepsis vs. controls. Septic platelets showed attenuated miR-26b, which were associated with disease severity and mortality. SELP mRNA level was elevated in sepsis, especially in platelets with increased mean platelet volume, causing higher P-selectin expression. Downregulation of Dicer1 generated lower miR-26b with higher SELP mRNA, while calpeptin restored miR-26b in MEG-01 cells. In conclusion, decreased miR-26b in MKs and platelets contributes to an increased level of platelet activation status in sepsis.
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Kerris EWJ, Hoptay C, Calderon T, Freishtat RJ. Platelets and platelet extracellular vesicles in hemostasis and sepsis. J Investig Med 2019; 68:813-820. [PMID: 31843956 DOI: 10.1136/jim-2019-001195] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2019] [Indexed: 01/09/2023]
Abstract
Platelets, cell fragments traditionally thought of as important only for hemostasis, substantially and dynamically contribute to the immune system's response to infection. In addition, there is increasing evidence that externally active platelet entities, including platelet granules and platelet extracellular vesicles (PEVs), play a role not only in hemostasis, but also in inflammatory actions previously ascribed to platelets themselves. Given the functions of platelets and PEVs during inflammation and infection, their role in sepsis is being investigated. Sepsis is a condition marked by the dysregulation of the body's normal activation of the immune system in response to a pathogen. The mechanisms for controlling infection locally become detrimental to the host if they are applied systemically. Similar to cells traditionally ascribed to the immune system, including neutrophils, lymphocytes, and macrophages, platelets are instrumental in helping a host clear an infection, but are also implicated in the uncontrolled amplification of the immune response that leads to sepsis. Clearly, the function of platelets is more complicated than its simple structure and primary role in hemostasis initially suggest. This review provides an overview of platelet and platelet extracellular vesicle structure and function, highlighting the complex role platelets and PEVs play in the body in the context of infection and sepsis.
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Affiliation(s)
- Elizabeth W J Kerris
- Division of Critical Care Medicine, Children's National Hospital, Washington, DC, USA.,Center for Genetic Medicine Research, Children's National Hospital, Washington, DC, USA
| | - Claire Hoptay
- Center for Genetic Medicine Research, Children's National Hospital, Washington, DC, USA
| | - Thais Calderon
- Department of Medical Education, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Robert J Freishtat
- Center for Genetic Medicine Research, Children's National Hospital, Washington, DC, USA.,Division of Emergency Medicine, Children's National Hospital, Washington, DC, USA
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20
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Hefele F, Ditsch A, Krysiak N, Caldwell CC, Biberthaler P, van Griensven M, Huber-Wagner S, Hanschen M. Trauma Induces Interleukin-17A Expression on Th17 Cells and CD4+ Regulatory T Cells as Well as Platelet Dysfunction. Front Immunol 2019; 10:2389. [PMID: 31681282 PMCID: PMC6797820 DOI: 10.3389/fimmu.2019.02389] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 09/23/2019] [Indexed: 12/18/2022] Open
Abstract
Background: The organism's immune response to trauma is distinctively controlled, its dysregulation leading to severe post-traumatic complications. Platelets, CD4+ regulatory T cells (CD4+ Tregs) and T helper 17 (Th17) cells have been identified to participate in the post-traumatic immune response. Unfortunately, little is known about their exact role and potential interdependency in humans. Aims of this clinical trial were to phenotype the human immune response following injury and to identify risk factors rendering the host more susceptible to trauma induced injury. Methods: This non-interventional prospective clinical trial enrolled patients following multiple trauma, follow up was conducted for 10 days. Peripheral blood CD4+ Tregs and Th17 cells were analyzed using flow cytometry to determine Interleukin 17A (IL-17A) expression. Hemostasis and platelet function were assessed with rotational thromboelastometry (ROTEM®). Subgroup analysis was conducted for the factors gender, age, and trauma severity. Results and Conclusion: This is the first clinical trial to phenotype the immune response following trauma, focusing on platelets, and the adaptive immune response. We discovered a novel increased IL-17A expression on Th17 cells and on CD4+ Tregs following trauma and describe the kinetics of the immune response. The IL-17A response on CD4+ Tregs challenges the ascribed role of CD4+ Tregs to be solely counter inflammatory in this setting. Furthermore, despite a rising number of platelets, ROTEM analysis shows post-traumatic platelet dysfunction. Subgroup analysis revealed gender, age, and trauma severity as influencing factors for several of the analyzed parameters.
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Affiliation(s)
- Friederike Hefele
- Experimental Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.,Division of Oncology and Hematology (CCM), Medical Department, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Alexander Ditsch
- Experimental Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Niels Krysiak
- Experimental Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.,Department of Trauma Surgery, Berufsgenossenschaftliche Unfallklinik Murnau, Murnau, Germany
| | - Charles C Caldwell
- Division of Research, Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH, United States.,Division of Research, Shriners Hospital for Children, Cincinnati, OH, United States
| | - Peter Biberthaler
- Department of Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Martijn van Griensven
- Experimental Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Stefan Huber-Wagner
- Department of Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
| | - Marc Hanschen
- Experimental Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany.,Department of Trauma Surgery, Klinikum rechts der Isar, Technical University of Munich, Munich, Germany
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21
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Sepsis alters the transcriptional and translational landscape of human and murine platelets. Blood 2019; 134:911-923. [PMID: 31366617 DOI: 10.1182/blood.2019000067] [Citation(s) in RCA: 102] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 07/10/2019] [Indexed: 12/30/2022] Open
Abstract
There is increasing recognition that platelets have a functional role in the pathophysiology of sepsis, though this role has not been precisely defined. Whether sepsis alters the human platelet transcriptome and translational landscape has never been established. We used parallel techniques of RNA sequencing and ribosome footprint profiling to interrogate the platelet transcriptome and translatome in septic patients and healthy donors. We identified 1806 significantly differentially expressed (false discovery rate <0.05) transcripts in platelets from septic patients. Platelet translational events during sepsis were also upregulated. To explore the relevance of a murine model of sepsis, cecal ligation and puncture (CLP), we compared sepsis-induced changes in platelet gene expression between septic patients and mice subjected to CLP. Platelet transcriptional (ρ = 0.42, P = 3.2 × 10-285) and translational (ρ = 0.65, P = 1.09 × 10-56) changes were significantly correlated between septic patients and mice. We focused on ITGA2B, tracking and validating the expression, regulation, and functional impact of changes in ITGA2B during sepsis. Increased ITGA2B was identified in bone marrow megakaryocytes within 24 hours of sepsis onset. Subsequent increases in ITGA2B were seen in circulating platelets, suggesting dynamic trafficking of the messenger RNA. Transcriptional changes in ITGA2B were accompanied by de novo protein synthesis of αIIb and integrin αIIbβ3 activation. Increased αIIb was associated with mortality in humans and mice. These findings provide previously unrecognized evidence that human and murine sepsis similarly alters the platelet transcriptional and translational landscape. Moreover, ITGA2B is upregulated and functional in sepsis due to trafficking from megakaryocytes and de novo synthesis in platelets and is associated with increased mortality.
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22
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Assinger A, Schrottmaier WC, Salzmann M, Rayes J. Platelets in Sepsis: An Update on Experimental Models and Clinical Data. Front Immunol 2019; 10:1687. [PMID: 31379873 PMCID: PMC6650595 DOI: 10.3389/fimmu.2019.01687] [Citation(s) in RCA: 147] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 07/04/2019] [Indexed: 12/22/2022] Open
Abstract
Beyond their important role in hemostasis, platelets play a crucial role in inflammatory diseases. This becomes apparent during sepsis, where platelet count and activation correlate with disease outcome and survival. Sepsis is caused by a dysregulated host response to infection, leading to organ dysfunction, permanent disabilities, or death. During sepsis, tissue injury results from the concomitant uncontrolled activation of the complement, coagulation, and inflammatory systems as well as platelet dysfunction. The balance between the systemic inflammatory response syndrome (SIRS) and the compensatory anti-inflammatory response (CARS) regulates sepsis outcome. Persistent thrombocytopenia is considered as an independent risk factor of mortality in sepsis, although it is still unclear whether the drop in platelet count is the cause or the consequence of sepsis severity. The role of platelets in sepsis development and progression was addressed in different experimental in vivo models, particularly in mice, that represent various aspects of human sepsis. The immunomodulatory function of platelets depends on the experimental model, time, and type of infection. Understanding the molecular mechanism of platelet regulation in inflammation could bring us one step closer to understand this important aspect of primary hemostasis which drives thrombotic as well as bleeding complications in patients with sterile and infectious inflammation. In this review, we summarize the current understanding of the contribution of platelets to sepsis severity and outcome. We highlight the differences between platelet receptors in mice and humans and discuss the potential and limitations of animal models to study platelet-related functions in sepsis.
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Affiliation(s)
- Alice Assinger
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | | | - Manuel Salzmann
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Julie Rayes
- Institute of Cardiovascular Science, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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23
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Role of sepsis modulated circulating microRNAs. EJIFCC 2019; 30:128-145. [PMID: 31263389 PMCID: PMC6599195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Sepsis is a life-threating condition with dysregulated systemic host response to microbial pathogens leading to disproportionate inflammatory response and multi-organ failure. Various biomarkers are available for the diagnosis and prognosis of sepsis; however, these laboratory parameters may show limitations in these severe clinical conditions. MicroRNAs (miRNA) are single-stranded non-coding RNAs with the function of post-transcriptional gene silencing. They normally control numerous intracellular events, such as signaling cascade downstream of Toll-like receptors (TLRs) to avoid excessive inflammation after infection. In contrast, abnormal miRNA expression contributes to the development of sepsis correlating with its clinical features and outcomes. Based on recent clinical studies altered levels of circulating miRNAs can act as potential diagnostic and prognostic biomarkers in sepsis. In this review, we summarized the available data about TLR-mediated inflammatory signaling with its intracellular response in immune cells and platelets upon sepsis, which are, at least in part, under the regulation of miRNAs. Furthermore, the role of circulating miRNAs is also described as potential laboratory biomarkers in sepsis.
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24
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Couldwell G, Machlus KR. Modulation of megakaryopoiesis and platelet production during inflammation. Thromb Res 2019; 179:114-120. [PMID: 31128560 DOI: 10.1016/j.thromres.2019.05.008] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 04/19/2019] [Accepted: 05/13/2019] [Indexed: 12/24/2022]
Abstract
Megakaryocytes (MKs) are widely known as the progenitor cells of platelets. These large, polyploid cells are a derivative of the hematopoietic stem cell (HSC), and reside in the bone marrow, lining blood vessel walls where they release their platelet progeny into circulation. Although little is known about how MKs differ under various environmental stressors, both chronic and acute inflammation alter the differentiation and molecular content of MKs. Furthermore, evidence suggests that the release of inflammatory cytokines may induce MK rupture and rapid release of platelets as a mechanism to quickly replenish diminished platelet counts in response to inflammation. Similarities between MKs and their close relatives, white blood cells, have introduced the notion that MKs may play a role in combating infection by engulfing and presenting antigens, and passing this information to circulating platelets. In addition, MKs exposed to varying bone marrow environments produce different platelets which enter circulation primed to respond to and combat inflammation, infection, or injury. This review focuses on how inflammation alters MK production, maturation, and platelet production. In addition, it introduces the idea that inflammation reprograms MKs to create different, more pathogenic platelets and leads them to take on different roles as responders to deleterious conditions. In the future, studies determining how platelets are altered in disease states may lead to novel MK- and platelet-based therapeutic targets to mitigate inflammation-related morbidity and mortality.
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Affiliation(s)
| | - Kellie R Machlus
- Division of Hematology, Brigham and Women's Hospital, Boston, MA 02115, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA.
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25
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Winer LK, Beckmann N, Veile RA, Goodman MD, Caldwell CC, Nomellini V. Consumptive coagulopathy is associated with organ dysfunction during PICS. Am J Physiol Lung Cell Mol Physiol 2019; 316:L946-L952. [PMID: 30840483 DOI: 10.1152/ajplung.00521.2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Patients who survive the acute phase of sepsis can progress to persistent inflammation, immunosuppression, and catabolism syndrome (PICS). Although sepsis is characterized by early hypercoagulability and delayed hypocoagulability, coagulopathy during chronic critical illness is not fully understood. The objective of this study was to determine whether sepsis-induced PICS is associated with coagulation abnormalities. Using our previously described murine PICS model, outbred mice underwent cecal ligation and puncture, and coagulability was characterized after 8 days. We found that during PICS the spleen became markedly enlarged with increased splenocytes and splenic megakaryocytes without a concomitant increase in circulating platelets. Microscopy revealed a nearly sevenfold increase in pulmonary microvascular thrombi in PICS mice, along with significantly decreased pulmonary tidal volumes and inspiratory times and with significantly increased respiratory rates. Thromboelastometry showed that PICS mice had significantly delayed clot initiation time but increased clot firmness. Finally, PICS mice displayed delayed thrombin production and decreased overall thrombin concentrations. All together, these data demonstrate a general dysregulation of coagulation resulting in microthrombus formation and compromised lung function. On the basis of these findings, we propose that consumptive coagulopathy constitutes another cardinal feature of PICS and may contribute to the ongoing tissue damage and multiple organ failure that can occur in chronic critical illness.
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Affiliation(s)
- Leah K Winer
- Division of Research, Department of Surgery, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Nadine Beckmann
- Division of Research, Department of Surgery, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Rosalie A Veile
- Division of Research, Department of Surgery, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Michael D Goodman
- Division of Research, Department of Surgery, University of Cincinnati College of Medicine , Cincinnati, Ohio.,Section of General Surgery, Department of Surgery, University of Cincinnati College of Medicine , Cincinnati, Ohio
| | - Charles C Caldwell
- Division of Research, Department of Surgery, University of Cincinnati College of Medicine , Cincinnati, Ohio.,Division of Research, Shriners Hospital for Children , Cincinnati, Ohio
| | - Vanessa Nomellini
- Section of General Surgery, Department of Surgery, University of Cincinnati College of Medicine , Cincinnati, Ohio.,Division of Research, Shriners Hospital for Children , Cincinnati, Ohio
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26
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Rondina MT, Zimmerman GA. The Role of Platelets in Inflammation. Platelets 2019. [DOI: 10.1016/b978-0-12-813456-6.00028-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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27
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Megakaryocyte Contribution to Bone Marrow Fibrosis: many Arrows in the Quiver. Mediterr J Hematol Infect Dis 2018; 10:e2018068. [PMID: 30416700 PMCID: PMC6223581 DOI: 10.4084/mjhid.2018.068] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 10/23/2018] [Indexed: 01/14/2023] Open
Abstract
In Primary Myelofibrosis (PMF), megakaryocyte dysplasia/hyperplasia determines the release of inflammatory cytokines that, in turn, stimulate stromal cells and induce bone marrow fibrosis. The pathogenic mechanism and the cells responsible for progression to bone marrow fibrosis in PMF are not completely understood. This review article aims to provide an overview of the crucial role of megakaryocytes in myelofibrosis by discussing the role and the altered secretion of megakaryocyte-derived soluble factors, enzymes and extracellular matrices that are known to induce bone marrow fibrosis.
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28
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Middleton EA, Rondina MT, Schwertz H, Zimmerman GA. Amicus or Adversary Revisited: Platelets in Acute Lung Injury and Acute Respiratory Distress Syndrome. Am J Respir Cell Mol Biol 2018; 59:18-35. [PMID: 29553813 PMCID: PMC6039872 DOI: 10.1165/rcmb.2017-0420tr] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2017] [Accepted: 02/20/2018] [Indexed: 12/21/2022] Open
Abstract
Platelets are essential cellular effectors of hemostasis and contribute to disease as circulating effectors of pathologic thrombosis. These are their most widely known biologic activities. Nevertheless, recent observations demonstrate that platelets have a much more intricate repertoire beyond these traditional functions and that they are specialized for contributions to vascular barrier integrity, organ repair, antimicrobial host defense, inflammation, and activities across the immune continuum. Paradoxically, on the basis of clinical investigations and animal models of disease, some of these newly discovered activities of platelets appear to contribute to tissue injury. Studies in the last decade indicate unique interactions of platelets and their precursor, the megakaryocyte, in the lung and implicate platelets as essential effectors in experimental acute lung injury and clinical acute respiratory distress syndrome. Additional discoveries derived from evolving work will be required to precisely define the contributions of platelets to complex subphenotypes of acute lung injury and to determine if these remarkable and versatile blood cells are therapeutic targets in acute respiratory distress syndrome.
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Affiliation(s)
- Elizabeth A. Middleton
- Division of Pulmonary and Critical Care Medicine, and
- Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah
| | - Matthew T. Rondina
- Division of General Internal Medicine, Department of Internal Medicine
- Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah
| | - Hansjorg Schwertz
- Division of Vascular Surgery, Department of Surgery, and
- Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah
| | - Guy A. Zimmerman
- Division of Pulmonary and Critical Care Medicine, and
- Program in Molecular Medicine, University of Utah School of Medicine, Salt Lake City, Utah
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29
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Zufferey A, Speck ER, Machlus KR, Aslam R, Guo L, McVey MJ, Kim M, Kapur R, Boilard E, Italiano JE, Semple JW. Mature murine megakaryocytes present antigen-MHC class I molecules to T cells and transfer them to platelets. Blood Adv 2017; 1:1773-1785. [PMID: 29296823 PMCID: PMC5728336 DOI: 10.1182/bloodadvances.2017007021] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 08/03/2017] [Indexed: 12/14/2022] Open
Abstract
Megakaryocytes (MKs) are bone marrow-derived cells that are primarily responsible for generating platelets for the maintenance of hemostasis. Although MK can variably express major histocompatibility complex (MHC) class I and II molecules during their differentiation, little is known whether they can elicit nonhemostatic immune functions such as T-cell activation. Here, we demonstrate that mature CD34- MHC class II- CD41+ MKs can endocytose exogenous ovalbumin (OVA) and proteolytically generate its immunogenic peptide ligand, which is crosspresented on their surface in association with MHC class I molecules. This crosspresentation triggered in vitro and in vivo OVA-specific CD8+ T-cell activation and proliferation. In addition, the OVA-MHC class I complexes were transferred from MK to pro-platelets upon thrombopoiesis in vitro. MK could also present endogenous MK-associated (CD61) peptides to activate CD61-specific CD8+ T cells and mediate immune thrombocytopenia in vivo. These results suggest that, in addition to their hemostatic role, mature MKs can significantly affect antigen-specific CD8+ T-cell responses via antigen presentation and are able to spread this immunogenic information through platelets.
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Affiliation(s)
- Anne Zufferey
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Edwin R Speck
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Kellie R Machlus
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Boston, MA
- Harvard Medical School, Boston, MA
| | - Rukhsana Aslam
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Li Guo
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Mark J McVey
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
- Departments of Anesthesia and Physiology, University of Toronto, Toronto, ON, Canada
| | - Michael Kim
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
| | - Rick Kapur
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
- Canadian Blood Services, Toronto, ON, Canada
| | - Eric Boilard
- Centre de Recherche du Centre Hospitalier Universitaire de Québec, Département de Microbiologie et Immunologie, Faculté de Médecine, Université Laval, Québec, QC, Canada
| | - Joseph E Italiano
- Division of Hematology, Department of Medicine, Brigham and Women's Hospital, Boston, MA
- Harvard Medical School, Boston, MA
- Vascular Biology Program, Department of Surgery, Children's Hospital Boston, Boston, MA
| | - John W Semple
- Toronto Platelet Immunobiology Group, Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, ON, Canada
- Canadian Blood Services, Toronto, ON, Canada
- Departments of Pharmacology, Medicine, and Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; and
- Division of Hematology and Transfusion Medicine, Lund University, Lund, Sweden
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30
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Thylur RP, Gowda R, Mishra S, Jun CD. Swiprosin-1: Its Expression and Diverse Biological Functions. J Cell Biochem 2017; 119:150-156. [PMID: 28590012 DOI: 10.1002/jcb.26199] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 06/06/2017] [Indexed: 02/02/2023]
Abstract
Swiprosin-1/EFhd2 is a Ca2+ binding adapter protein involved in the various cellular functions. Swiprosin-1 is significantly upregulated in a number of pathological conditions of inflammation, neurodegeneration, and cancer. Swiprosin-1 associated with actin and its expression level amplifies the production of proinflammatory mediators and modulates the activation of transcription factor during immune cells activation. This review aims at providing an overview of the expression and function of swiprosin-1/EFhd2 in various pathophysiological conditions. We also discussed the key role of swiprosin-1 in immune cell activation, cell migration, apoptosis, humoral immunity, cancer invasion and metastasis, neuronal transport, and major signaling cascades. J. Cell. Biochem. 119: 150-156, 2018. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Ramesh P Thylur
- School of Life Science, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
| | - Raghavendra Gowda
- Department of Pharmacology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania
| | - Sumita Mishra
- Department of Pediatrics, Division of Medicine, Johns Hopkins Medical Institutions, Baltimore, Maryland
| | - Chang-Duk Jun
- School of Life Science, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
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31
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N-glycosylation of human sphingomyelin phosphodiesterase acid-like 3A (SMPDL3A) is essential for stability, secretion and activity. Biochem J 2017; 474:1071-1092. [PMID: 28104755 DOI: 10.1042/bcj20160735] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 01/14/2017] [Accepted: 01/18/2017] [Indexed: 11/17/2022]
Abstract
Sphingomyelin phosphodiesterase acid-like 3A (SMPDL3A) is a recently identified phosphodiesterase, which is a secreted N-linked glycoprotein. SMPDL3A is highly homologous to acid sphingomyelinase (aSMase), but unlike aSMase cannot cleave sphingomyelin. Rather, SMPDL3A hydrolyzes nucleotide tri- and diphosphates and their derivatives. While recent structural studies have shed light on these unexpected substrate preferences, many other aspects of SMPDL3A biology, which may give insight into its function in vivo, remain obscure. Here, we investigate the roles of N-glycosylation in the expression, secretion and activity of human SMPDL3A, using inhibitors of N-glycosylation and site-directed mutagenesis, with either THP-1 macrophages or CHO cells expressing human SMPDL3A. Tunicamycin (TM) treatment resulted in expression of non-glycosylated SMPDL3A that was not secreted, and was largely degraded by the proteasome. Proteasomal inhibition restored levels of SMPDL3A in TM-treated cells, although this non-glycosylated protein lacked phosphodiesterase activity. Enzymatic deglycosylation of purified recombinant SMPDL3A also resulted in significant loss of phosphodiesterase activity. Site-directed mutagenesis of individual N-glycosylation sites in SMPDL3A identified glycosylation of Asn69 and Asn222 as affecting maturation of its N-glycans and secretion. Glycosylation of Asn356 in SMPDL3A, an N-linked site conserved throughout the aSMase-like family, was critical for protection against proteasomal degradation and preservation of enzymatic activity. We provide the first experimental evidence for a predicted 22 residue N-terminal signal peptide in SMPDL3A, which is essential for facilitating glycosylation and is removed from the mature protein secreted from CHO cells. In conclusion, site-specific N-glycosylation is essential for the intracellular stability, secretion and activity of human SMPDL3A.
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32
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Nong Q, Li S, Liu D. A comprehensive bioinformatics method to screen key genes for severe burn. EUR J INFLAMM 2015. [DOI: 10.1177/1721727x15622459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Severe burn is a kind of traumatic injury, which can lead to serious financial burden, high morbidity and mortality following inflammatory response and complications. Microarray analysis has emerged as a popular tool for generating gene expression data and revealing the complex gene expression patterns. The Gene Expression Omnibus (GEO) repository at the National Center for Biotechnology Information has become the leading public repository of microarray data. This study aimed to study the mechanisms of severe burn. Microarray of GSE37069 was downloaded from GEO including blood samples from 244 severe burn patients and blood samples from 35 healthy controls. The differentially expressed genes (DEGs) between blood samples from healthy controls and patients were identified by t-test in the LIMMA package of R. Their interaction relationships were searched using STRING online software and then protein-protein interaction (PPI) network was constructed by Cytoscape. Using DAVID online tool, underlying functions of the DEGs involved in the PPI network were analyzed by functional and pathway enrichment analyses. We screened 541 DEGs in blood samples from severe burns patients compared with blood samples from healthy controls. Meanwhile, DEGs including MMP9, TIMP1, GZMK, GZMA, and GZMB showed higher degrees in the PPI networks. Moreover, they may function in severe burn through interacting with others. According to functional enrichment analysis, these DEGs were mainly involved in BP categories associated with inflammatory responses. MMP9, TIMP1, HGF, GZMA, GZMB, and GZMK might play important roles in severe burns.
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Affiliation(s)
- Qingwen Nong
- Burns & Plastic Surgery, the First Affiliate Hospital of Guangxi Medical University, Nanning, Guangxi, PR China
| | - Shuntang Li
- Burns & Plastic Surgery, the First Affiliate Hospital of Guangxi Medical University, Nanning, Guangxi, PR China
| | - Daen Liu
- Burns & Plastic Surgery, the First Affiliate Hospital of Guangxi Medical University, Nanning, Guangxi, PR China
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Marcet-Palacios M, Ewen C, Pittman E, Duggan B, Carmine-Simmen K, Fahlman RP, Bleackley RC. Design and characterization of a novel human Granzyme B inhibitor. Protein Eng Des Sel 2014; 28:9-17. [DOI: 10.1093/protein/gzu052] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Abstract
Thrombocytopenia is a common finding in sepsis and associated with a worse outcome. We used a mouse model of pneumonia-derived sepsis caused by the human pathogen Klebsiella pneumoniae to study the role of platelets in host response to sepsis. Platelet counts (PCs) were reduced to less than a median of 5 × 10(9)/L or to 5 to 13 × 10(9)/L by administration of a depleting antibody in mice infected with Klebsiella via the airways. Thrombocytopenia was associated with strongly impaired survival during pneumonia-derived sepsis proportional to the extent of platelet depletion. Thrombocytopenic mice demonstrated PC-dependent enhanced bacterial growth in lungs, blood, and distant organs. Severe thrombocytopenia resulted in hemorrhage at the primary site of infection, but not in distant organs. PCs of 5 to 13 × 10(9)/L were sufficient to largely maintain hemostasis in infected lungs. Thrombocytopenia did not influence lung inflammation or neutrophil recruitment and did not attenuate local or systemic activation of coagulation or the vascular endothelium. PCs <5 × 10(9)/L even resulted in enhanced coagulation and endothelial cell activation, which coincided with increased proinflammatory cytokine levels. In accordance, low PCs in whole blood enhanced Klebsiella-induced cytokine release in vitro. These data suggest that platelets play an important role in host defense to Klebsiella pneumosepsis.
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The adaptor protein Swiprosin-1/EFhd2 is dispensable for platelet function in mice. PLoS One 2014; 9:e107139. [PMID: 25243606 PMCID: PMC4170979 DOI: 10.1371/journal.pone.0107139] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 08/06/2014] [Indexed: 11/19/2022] Open
Abstract
Background Platelets are anuclear cell fragments derived from bone marrow megakaryocytes that safeguard vascular integrity, but may also cause pathological vessel occlusion. Reorganizations of the platelet cytoskeleton and agonist-induced intracellular Ca2+-mobilization are crucial for platelet hemostatic function. EF-hand domain containing 2 (EFhd2, Swiprosin-1) is a Ca2+-binding cytoskeletal adaptor protein involved in actin remodeling in different cell types, but its function in platelets is unknown. Objective Based on the described functions of EFhd2 in immune cells, we tested the hypothesis that EFhd2 is a crucial adaptor protein for platelet function acting as a regulator of Ca2+-mobilization and cytoskeletal rearrangements. Methods and Results We generated EFhd2-deficient mice and analyzed their platelets in vitro and in vivo. Efhd2-/- mice displayed normal platelet count and size, exhibited an unaltered in vivo life span and showed normal Ca2+-mobilization and activation/aggregation responses to classic agonists. Interestingly, upon stimulation of the immunoreceptor tyrosine-based activation motif-coupled receptor glycoprotein (GP) VI, Efhd2-/- platelets showed a slightly increased coagulant activity. Furthermore, absence of EFhd2 had no significant impact on integrin-mediated clot retraction, actomyosin rearrangements and spreading of activated platelets on fibrinogen. In vivo EFhd2-deficiency resulted in unaltered hemostatic function and unaffected arterial thrombus formation. Conclusion These results show that EFhd2 is not essential for platelet function in mice indicating that other cytoskeletal adaptors may functionally compensate its loss.
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de Stoppelaar SF, van 't Veer C, van der Poll T. The role of platelets in sepsis. Thromb Haemost 2014; 112:666-77. [PMID: 24966015 DOI: 10.1160/th14-02-0126] [Citation(s) in RCA: 146] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Accepted: 04/16/2014] [Indexed: 01/01/2023]
Abstract
Platelets are small circulating anucleate cells that are of crucial importance in haemostasis. Over the last decade, it has become increasingly clear that platelets play an important role in inflammation and can influence both innate and adaptive immunity. Sepsis is a potentially lethal condition caused by detrimental host response to an invading pathogen. Dysbalanced immune response and activation of the coagulation system during sepsis are fundamental events leading to sepsis complications and organ failure. Platelets, being major effector cells in both haemostasis and inflammation, are involved in sepsis pathogenesis and contribute to sepsis complications. Platelets catalyse the development of hyperinflammation, disseminated intravascular coagulation and microthrombosis, and subsequently contribute to multiple organ failure. Inappropriate accumulation and activity of platelets are key events in the development of sepsis-related complications such as acute lung injury and acute kidney injury. Platelet activation readouts could serve as biomarkers for early sepsis recognition; inhibition of platelets in septic patients seems like an important target for immune-modulating therapy and appears promising based on animal models and retrospective human studies.
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Affiliation(s)
- Sacha F de Stoppelaar
- Sacha F. de Stoppelaar, MD, Academic Medical Centre, Centre of Experimental and Molecular Medicine, Meibergdreef 9, Room G2-130, 1105 AZ Amsterdam, the Netherlands, Tel.: +31 20 5665910, Fax: +31 20 6977192, E-mail:
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Alder MN, Lindsell CJ, Wong HR. The pediatric sepsis biomarker risk model: potential implications for sepsis therapy and biology. Expert Rev Anti Infect Ther 2014; 12:809-16. [PMID: 24754535 DOI: 10.1586/14787210.2014.912131] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Sepsis remains a major cause of morbidity and mortality in adult and pediatric intensive care units. Heterogeneity of demographics, comorbidities, biological mechanisms, and severity of illness leads to difficulty in determining which patients are at highest risk of mortality. Determining mortality risk is important for weighing the potential benefits of more aggressive interventions and for deciding whom to enroll in clinical trials. Biomarkers can be used to parse patients into different risk categories and can outperform current methods of patient risk stratification based on physiologic parameters. Here we review the Pediatric Sepsis Biomarker Risk Model that has also been modified and applied to estimate mortality risk in adult patients. We compare the two models and speculate on the biological implications of the biomarkers in patients with sepsis.
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Affiliation(s)
- Matthew N Alder
- Division of Critical Care Medicine, Cincinnati Children's Hospital Medical Center and Cincinnati Children's Research Foundation, Cincinnati, OH, USA
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Use of antiplatelet agents in sepsis: A glimpse into the future. Thromb Res 2014; 133:131-8. [DOI: 10.1016/j.thromres.2013.07.002] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 07/04/2013] [Accepted: 07/08/2013] [Indexed: 11/21/2022]
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Joeckel LT, Bird PI. Are all granzymes cytotoxic in vivo? Biol Chem 2014; 395:181-202. [DOI: 10.1515/hsz-2013-0238] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Accepted: 08/30/2013] [Indexed: 01/01/2023]
Abstract
Abstract
Granzymes are serine proteases mainly found in cytotoxic lymphocytes. The most-studied member of this group is granzyme B, which is a potent cytotoxin that has set the paradigm that all granzymes are cyototoxic. In the last 5 years, this paradigm has become controversial. On one hand, there is a plethora of sometimes contradictory publications showing mainly caspase-independent cytotoxic effects of granzyme A and the so-called orphan granzymes in vitro. On the other hand, there are increasing numbers of reports of granzymes failing to induce cell death in vitro unless very high (potentially supra-physiological) concentrations are used. Furthermore, experiments with granzyme A or granzyme M knock-out mice reveal little or no deficit in their cytotoxic lymphocytes’ killing ability ex vivo, but indicate impairment in the inflammatory response. These findings of non-cytotoxic effects of granzymes challenge dogma, and thus require alternative or additional explanations to be developed of the role of granzymes in defeating pathogens. Here we review evidence for granzyme cytotoxicity, give an overview of their non-cytotoxic functions, and suggest technical improvements for future investigations.
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Abstract
Besides mediating primary hemostasis and thrombosis, platelets play a critical role in tissue repair and regeneration. They regulate fundamental mechanisms involved in the healing process including cellular migration, proliferation, and angiogenesis. Control of apoptosis/cell survival and interaction with progenitor cells, which are clinically relevant but poorly understood aspects of platelets in tissue repair, will be highlighted in this review. Gaining deeper insight into the less well-characterized molecular mechanisms is necessary to develop new therapeutic platelet-based options.
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Wong HR, Salisbury S, Xiao Q, Cvijanovich NZ, Hall M, Allen GL, Thomas NJ, Freishtat RJ, Anas N, Meyer K, Checchia PA, Lin R, Shanley TP, Bigham MT, Sen A, Nowak J, Quasney M, Henricksen JW, Chopra A, Banschbach S, Beckman E, Harmon K, Lahni P, Lindsell CJ. The pediatric sepsis biomarker risk model. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2012; 16:R174. [PMID: 23025259 PMCID: PMC3682273 DOI: 10.1186/cc11652] [Citation(s) in RCA: 136] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Accepted: 10/01/2012] [Indexed: 12/19/2022]
Abstract
INTRODUCTION The intrinsic heterogeneity of clinical septic shock is a major challenge. For clinical trials, individual patient management, and quality improvement efforts, it is unclear which patients are least likely to survive and thus benefit from alternative treatment approaches. A robust risk stratification tool would greatly aid decision-making. The objective of our study was to derive and test a multi-biomarker-based risk model to predict outcome in pediatric septic shock. METHODS Twelve candidate serum protein stratification biomarkers were identified from previous genome-wide expression profiling. To derive the risk stratification tool, biomarkers were measured in serum samples from 220 unselected children with septic shock, obtained during the first 24 hours of admission to the intensive care unit. Classification and Regression Tree (CART) analysis was used to generate a decision tree to predict 28-day all-cause mortality based on both biomarkers and clinical variables. The derived tree was subsequently tested in an independent cohort of 135 children with septic shock. RESULTS The derived decision tree included five biomarkers. In the derivation cohort, sensitivity for mortality was 91% (95% CI 70 - 98), specificity was 86% (80 - 90), positive predictive value was 43% (29 - 58), and negative predictive value was 99% (95 - 100). When applied to the test cohort, sensitivity was 89% (64 - 98) and specificity was 64% (55 - 73). In an updated model including all 355 subjects in the combined derivation and test cohorts, sensitivity for mortality was 93% (79 - 98), specificity was 74% (69 - 79), positive predictive value was 32% (24 - 41), and negative predictive value was 99% (96 - 100). False positive subjects in the updated model had greater illness severity compared to the true negative subjects, as measured by persistence of organ failure, length of stay, and intensive care unit free days. CONCLUSIONS The pediatric sepsis biomarker risk model (PERSEVERE; PEdiatRic SEpsis biomarkEr Risk modEl) reliably identifies children at risk of death and greater illness severity from pediatric septic shock. PERSEVERE has the potential to substantially enhance clinical decision making, to adjust for risk in clinical trials, and to serve as a septic shock-specific quality metric.
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Sharron M, Hoptay CE, Wiles AA, Garvin LM, Geha M, Benton AS, Nagaraju K, Freishtat RJ. Platelets induce apoptosis during sepsis in a contact-dependent manner that is inhibited by GPIIb/IIIa blockade. PLoS One 2012; 7:e41549. [PMID: 22844498 PMCID: PMC3406039 DOI: 10.1371/journal.pone.0041549] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 06/27/2012] [Indexed: 01/08/2023] Open
Abstract
Purpose End-organ apoptosis is well-described in progressive sepsis and Multiple Organ Dysfunction Syndrome (MODS), especially where platelets accumulate (e.g. spleen and lung). We previously reported an acute sepsis-induced cytotoxic platelet phenotype expressing serine protease granzyme B. We now aim to define the site(s) of and mechanism(s) by which platelet granzyme B induces end-organ apoptosis in sepsis. Methods End-organ apoptosis in murine sepsis (i.e. polymicrobial peritonitis) was analyzed by immunohistochemistry. Platelet cytotoxicity was measured by flow cytometry following 90 minute ex vivo co-incubation with healthy murine splenocytes. Sepsis progression was measured via validated preclinical murine sepsis score. Measurements and Main Results There was evident apoptosis in spleen, lung, and kidney sections from septic wild type mice. In contrast, there was a lack of TUNEL staining in spleens and lungs from septic granzyme B null mice and these mice survived longer following induction of sepsis than wild type mice. In co-incubation experiments, physical separation of septic platelets from splenocytes by a semi-permeable membrane reduced splenocyte apoptosis to a rate indistinguishable from negative controls. Chemical separation by the platelet GPIIb/IIIa receptor inhibitor eptifibatide decreased apoptosis by 66.6±10.6% (p = 0.008). Mice treated with eptifibatide in vivo survived longer following induction of sepsis than vehicle control mice. Conclusions In sepsis, platelet granzyme B-mediated apoptosis occurs in spleen and lung, and absence of granzyme B slows sepsis progression. This process proceeds in a contact-dependent manner that is inhibited ex vivo and in vivo by the platelet GPIIb/IIIa receptor inhibitor eptifibatide. The GPIIb/IIIa inhibitors and other classes of anti-platelet drugs may be protective in sepsis.
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Affiliation(s)
- Matthew Sharron
- Division of Critical Care Medicine, Children’s National Medical Center, Washington, D.C., United States of America
- Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
- Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
| | - Claire E. Hoptay
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington, D.C., United States of America
- Department of Microbiology, Immunology, and Tropical Medicine, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
| | - Andrew A. Wiles
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington, D.C., United States of America
| | - Lindsay M. Garvin
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington, D.C., United States of America
- Department of Microbiology, Immunology, and Tropical Medicine, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
| | - Mayya Geha
- Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
| | - Angela S. Benton
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington, D.C., United States of America
| | - Kanneboyina Nagaraju
- Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
- Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington, D.C., United States of America
| | - Robert J. Freishtat
- Department of Pediatrics, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
- Department of Integrative Systems Biology, George Washington University School of Medicine and Health Sciences, Washington, D.C., United States of America
- Research Center for Genetic Medicine, Children’s National Medical Center, Washington, D.C., United States of America
- Division of Emergency Medicine, Children’s National Medical Center, Washington, D.C., United States of America
- * E-mail:
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Zhou Y, Zhang H, Sun XJ, Zheng D, Liang YJ, Luo J, Wang Y, Zhang ZS. Murine CD8+T cell cytotoxicity against schistosomula induced by inoculation of schistosomal 22.6/26GST coupled Sepharose 4B beads. Vaccine 2012; 30:2440-7. [DOI: 10.1016/j.vaccine.2012.01.068] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 01/16/2012] [Accepted: 01/21/2012] [Indexed: 10/14/2022]
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Abstract
OBJECTIVE The cytopathic hypoxia theory proposes that there is an impaired cellular oxygen utilization during sepsis. Respiratory complex IV, or cytochrome c oxidase, was only previously studied in muscle biopsies of 16 surviving and 12 nonsurviving septic patients. We hypothesized that higher activities and quantities of this enzyme complex could be associated with septic patient survival. The objective was to evaluate the relationship between cytochrome c oxidase activities and quantities and 6-month survival in a larger series of septic patients using a less invasive method (circulating platelets). DESIGN Prospective, multicenter, observational study. SETTING The study was carried out in six Spanish intensive care units. PATIENTS We included 96 septic patients. INTERVENTIONS We determined the cytochrome c oxidase activity per citrate synthase activity ratio and cytochrome c oxidase quantity per citrate synthase activity ratio in circulating platelets at the time of diagnosis and related them to 6-month survival. The written informed consent from the family members was obtained. MEASUREMENTS AND MAIN RESULTS Survivor patients (n = 54) showed higher cytochrome c oxidase activity per citrate synthase activity ratio (p = .04) and cytochrome c oxidase quantity per citrate synthase activity ratio (p = .006) than nonsurvivors (n = 42). Logistic regression analyses confirmed that the cytochrome c oxidase activity per citrate synthase activity ratio (p = .04) and cytochrome c oxidase quantity per citrate synthase activity ratio (p = .02) were independent predictors of 6-month survival. The area under the curve to predict 6-month survival was 0.62 (95% confidence interval 0.51-0.74; p = .04) for the cytochrome c oxidase activity per citrate synthase activity ratio and 0.67 (95% confidence interval 0.56-0.76; p = .003) for the cytochrome c oxidase quantity per citrate synthase activity ratio. A negative correlation was found between the cytochrome c oxidase quantity per citrate synthase activity ratio and Sepsis-Related Organ Failure Assessment score (p = .04). CONCLUSIONS Platelet cytochrome c oxidase activity and quantity were independent predictors of 6-month survival and could be used as biomarkers of sepsis mortality. This is a rapid, easy, and less invasive protocol to assess mitochondrial function. Patients with lower cytochrome c oxidase activity and quantity could benefit from drugs that improve mitochondrial function.
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Vieira-de-Abreu A, Campbell RA, Weyrich AS, Zimmerman GA. Platelets: versatile effector cells in hemostasis, inflammation, and the immune continuum. Semin Immunopathol 2011; 34:5-30. [PMID: 21818701 DOI: 10.1007/s00281-011-0286-4] [Citation(s) in RCA: 217] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Accepted: 07/20/2011] [Indexed: 12/28/2022]
Abstract
Platelets are chief effector cells in hemostasis. In addition, however, their specializations include activities and intercellular interactions that make them key effectors in inflammation and in the continuum of innate and adaptive immunity. This review focuses on the immune features of human platelets and platelets from experimental animals and on interactions between inflammatory, immune, and hemostatic activities of these anucleate but complex and versatile cells. The experimental findings and evidence for physiologic immune functions include previously unrecognized biologic characteristics of platelets and are paralleled by new evidence for unique roles of platelets in inflammatory, immune, and thrombotic diseases.
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Affiliation(s)
- Adriana Vieira-de-Abreu
- Department of Medicine, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
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Abstract
Sepsis, acute lung injury, and ARDS contribute substantially to the expanding burden of critical illness within our ICUs. Each of these processes is characterized by a myriad of injurious events, including apoptosis, microvascular dysfunction, abnormal coagulation, and dysregulated host immunity. Only recently have platelets--long considered merely effectors of thrombosis--been implicated in inflammatory conditions and the pathobiology of these disease processes. A growing body of evidence suggests a prominent role for maladaptive platelet activation and aggregation during sepsis and ARDS and has begun to underscore the pluripotential influence of platelets on outcomes in critical illness. Not only do platelets enhance vascular injury through thrombotic mechanisms but also appear to help orchestrate pathologic immune responses and are pivotal players in facilitating leukocyte recruitment to vulnerable tissue. These events contribute to the organ damage and poor patient outcomes that still plague the care of these high-risk individuals. An understanding of the role of platelets in critical illness also highlights the potential for both the development of risk stratification schema and the use of novel, targeted therapies that might alter the natural history of sepsis, acute lung injury, and ARDS. Future studies of adenosine, platelet polyphosphates, and the platelet transcriptome/proteome also should add considerably to our ability to unravel the mysteries of the versatile platelet.
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Affiliation(s)
- Jason N Katz
- Divisions of Cardiology and Pulmonary & Critical Care, The University of North Carolina, Chapel Hill, NC.
| | | | - Richard C Becker
- Divisions of Cardiology and Hematology, Duke Clinical Research Institute, Duke University Medical Center, Durham, NC
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Rondina MT, Schwertz H, Harris ES, Kraemer BF, Campbell RA, Mackman N, Grissom CK, Weyrich AS, Zimmerman GA. The septic milieu triggers expression of spliced tissue factor mRNA in human platelets. J Thromb Haemost 2011; 9:748-58. [PMID: 21255247 PMCID: PMC3071458 DOI: 10.1111/j.1538-7836.2011.04208.x] [Citation(s) in RCA: 106] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Activated platelets have previously-unrecognized mechanisms of post-transcriptional gene expression that may influence hemostasis and inflammation. A novel pathway involves splicing of pre-mRNAs in resting platelets to mature, translatable mRNAs in response to cellular activation. OBJECTIVES We asked if bacterial products and host agonists present in the septic milieu induce tissue factor pre-mRNA splicing in platelets from healthy subjects. In parallel, we asked if spliced tissue factor (TF) mRNA is present in platelets from septic patients in a proof-of-principle analysis. PATIENTS/METHODS TF pre-mRNA and mRNA expression patterns were characterized in platelets from septic patients and in platelets isolated from healthy subjects activated with bacteria, toxins and inflammatory agonists. Procoagulant activity was also measured. RESULTS AND CONCLUSIONS Live bacteria, staphylococcal α-toxin and lipopolysaccharide (LPS) induced TF pre-mRNA splicing in platelets isolated from healthy subjects. Toxin-stimulated platelets accelerated plasma clotting, a response that was blocked by a previously-characterized splicing inhibitor and by an anti-tissue factor antibody. Platelets from septic patients expressed spliced TF mRNA, whereas it was absent from unselected and age-matched control subjects. Tissue factor-dependent procoagulant activity was elevated in platelets from a subset of septic patients. Thus, bacterial and host factors induce splicing of TF pre-mRNA, expression of TF mRNA and tissue factor-dependent clotting activity in human platelets. TF mRNA is present in platelets from some septic patients, indicating that it may be a marker of altered platelet phenotype and function in sepsis and that splicing pathways are induced in this syndrome.
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Affiliation(s)
- M T Rondina
- Division of General Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT 84132, USA.
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Benton AS, Wang Z, Lerner J, Foerster M, Teach SJ, Freishtat RJ. Overcoming heterogeneity in pediatric asthma: tobacco smoke and asthma characteristics within phenotypic clusters in an African American cohort. J Asthma 2010; 47:728-34. [PMID: 20684733 DOI: 10.3109/02770903.2010.491142] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Asthma in children and adolescents is a heterogeneous syndrome comprised of multiple subgroups with variable disease expression and response to environmental exposures. The goal of this study was to define homogeneous phenotypic clusters within a cohort of children and adolescents with asthma and to determine overall and within-cluster associations between environmental tobacco smoke (ETS) exposure and asthma characteristics. METHODS A combined hierarchical/k-means cluster analysis of principal component variables was used to define phenotypic clusters within a cohort of 6- to 20-year-old urban and largely minority subjects. RESULTS Among the 154 subjects, phenotypic cluster analysis defined three independent clusters (Cluster 1 [n = 57]; Cluster 2 [n = 33]; Cluster 3 [n = 58]). A small fourth cluster (n = 6) was excluded. Patients in Cluster 1 were predominantly males, with a relative abundance of neutrophils in their nasal washes. Patients in Cluster 2 were predominantly females with high body mass index percentiles and later-onset asthma. Patients in Cluster 3 had higher eosinophil counts in their nasal washes and lower Asthma Control Test (ACT) scores. Within-cluster regression analysis revealed several significant associations between ETS exposure and phenotypic characteristics that were not present in the overall cohort. ETS exposure was associated with a significant increase in nasal wash neutrophils (beta coefficient = 0.73 [95% confidence interval, CI: 0.11 to 1.35]; p = .023) and a significant decrease in ACT score (-5.17 [-8.42 to -1.93]; p = .003) within Cluster 1 and a significant reduction in the bronchodilator-induced % change in forced expiratory volume in one second (FEV(1)) (-36.32 [-62.18 to -10.46]; p = .009) within Cluster 3. CONCLUSIONS Clustering techniques defined more homogeneous subgroups, allowing for the detection of otherwise undetectable associations between environmental tobacco smoke exposure and asthma characteristics.
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Affiliation(s)
- Angela S Benton
- Genomics and Bioinformatics Program, Columbian College of Arts and Sciences, George Washington University, and Children’s National Medical Center,Washington, D.C., U.S.A
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Abstract
OBJECTIVE To directly assess whether genomewide expression profiles derived from leukocyte subsets are comparable to that of whole blood as measured by enrichment for genes corresponding to metabolic and signaling pathways. DESIGN Prospective observational study involving microarray-based bioinformatics based on RNA individually derived from whole blood, neutrophils, monocytes, and lymphocytes, respectively. SETTING Three pediatric intensive care units in the United States. PATIENTS Children < or =10 yrs of age: five normal control subjects and 13 meeting criteria for septic shock on day 1 of presentation to the pediatric intensive care unit. INTERVENTIONS None other than standard care. MEASUREMENTS AND MAIN RESULTS Baseline analyses using whole blood-derived RNA demonstrated increased expression of genes corresponding to signaling pathways involving innate immunity, redox balance, and protein ubiquitination and decreased expression of genes corresponding to the adaptive immune system. Subsequent analyses using leukocyte-specific RNA were congruent with the gene expression profiles demonstrated using whole blood-derived RNA as measured by enrichment for genes corresponding to metabolic and signaling pathways. Gene network analysis, derived from a composite gene list involving the individual gene expression profiles of neutrophils, monocytes, and lymphocytes, respectively, revealed a gene network corresponding to antigen presentation, cell-mediated immunity, and humoral-mediated immunity. Finally, a subanalysis focused on network gene nodes localized to the nuclear compartment revealed functional annotations related to transcriptional repression and epigenetic regulation. CONCLUSIONS These data demonstrate that genome-level repression of adaptive immunity gene programs early in the course of pediatric septic shock remained evident when analyses were conducted using leukocyte subset-specific RNA.
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