24
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Leukocyte integrin Mac-1 regulates thrombosis via interaction with platelet GPIbα

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Inflammation and thrombosis occur together in many diseases. The leukocyte integrin Mac-1 (also known as integrin α Mβ 2, or CD11b/CD18) is crucial for leukocyte recruitment to the endothelium, and Mac-1 engagement of platelet GPIbα is required for injury responses in diverse disease models. However, the role of Mac-1 in thrombosis is undefined. Here we report that mice with Mac-1 deficiency ( Mac-1 −/− ) or mutation of the Mac-1-binding site for GPIbα have delayed thrombosis after carotid artery and cremaster microvascular injury without affecting parameters of haemostasis. Adoptive wild-type leukocyte transfer rescues the thrombosis defect in Mac-1 −/− mice, and Mac-1-dependent regulation of the transcription factor Foxp1 contributes to thrombosis as evidenced by delayed thrombosis in mice with monocyte-/macrophage-specific overexpression of Foxp1. Antibody and small-molecule targeting of Mac-1:GPIbα inhibits thrombosis. Our data identify a new pathway of thrombosis involving leukocyte Mac-1 and platelet GPIbα, and suggest that targeting this interaction has anti-thrombotic therapeutic potential with reduced bleeding risk.

          Abstract

          The binding of the leukocyte integrin Mac1 to the platelet receptor GPIbα is important for the physiological response to tissue injury. Here the authors show that this interaction also regulates thrombosis, without influencing bleeding time, which may provide clues for the development of new anti-thrombotic drugs.

          Related collections

          Most cited references73

          • Record: found
          • Abstract: found
          • Article: found
          Is Open Access

          PAD4 is essential for antibacterial innate immunity mediated by neutrophil extracellular traps

          Neutrophils trap and kill bacteria by forming highly decondensed chromatin structures, termed neutrophil extracellular traps (NETs). We previously reported that histone hypercitrullination catalyzed by peptidylarginine deiminase 4 (PAD4) correlates with chromatin decondensation during NET formation. However, the role of PAD4 in NET-mediated bacterial trapping and killing has not been tested. Here, we use PAD4 knockout mice to show that PAD4 is essential for NET-mediated antibacterial function. Unlike PAD4+/+ neutrophils, PAD4−/− neutrophils cannot form NETs after stimulation with chemokines or incubation with bacteria, and are deficient in bacterial killing by NETs. In a mouse infectious disease model of necrotizing fasciitis, PAD4−/− mice are more susceptible to bacterial infection than PAD4+/+ mice due to a lack of NET formation. Moreover, we found that citrullination decreased the bacterial killing activity of histones and nucleosomes, which suggests that PAD4 mainly plays a role in chromatin decondensation to form NETs instead of increasing histone-mediated bacterial killing. Our results define a role for histone hypercitrullination in innate immunity during bacterial infection.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            Adverse impact of bleeding on prognosis in patients with acute coronary syndromes.

            The use of multiple antithrombotic drugs and aggressive invasive strategies has increased the risk of major bleeding in acute coronary syndrome (ACS) patients. It is not known to what extent bleeding determines clinical outcome. Using Cox proportional-hazards modeling, we examined the association between bleeding and death or ischemic events in 34,146 patients with ACS enrolled in the Organization to Assess Ischemic Syndromes and the Clopidogrel in Unstable Angina to Prevent Recurrent Events studies. Patients with major bleeding were older, more often had diabetes or a history of stroke, had a lower blood pressure and higher serum creatinine, more often had ST-segment changes on the presenting ECG, and had a 5-fold-higher incidence of death during the first 30 days (12.8% versus 2.5%; P < 0.0001) and a 1.5-fold-higher incidence of death between 30 days and 6 months (4.6% versus 2.9%; P = 0.002). Major bleeding was independently associated with an increased hazard of death during the first 30 days (hazard ratio, 5.37; 95% CI, 3.97 to 7.26; P < 0.0001), but the hazard was much weaker after 30 days (hazard ratio, 1.54; 95% CI, 1.01 to 2.36; P = 0.047). The association was consistent across subgroups according to cointerventions during hospitalization, and there was an increasing risk of death with increasing severity of bleeding (minor less than major less than life-threatening; P for trend = 0.0009). A similar association was evident between major bleeding and ischemic events, including myocardial infarction and stroke. In ACS patients without persistent ST-segment elevation, there is a strong, consistent, temporal, and dose-related association between bleeding and death. These data should lead to greater awareness of the prognostic importance of bleeding in ACS and should prompt evaluation of strategies to reduce bleeding and thereby improve clinical outcomes.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              Bivalirudin during primary PCI in acute myocardial infarction.

              Treatment with the direct thrombin inhibitor bivalirudin, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, results in similar suppression of ischemia while reducing hemorrhagic complications in patients with stable angina and non-ST-segment elevation acute coronary syndromes who are undergoing percutaneous coronary intervention (PCI). The safety and efficacy of bivalirudin in high-risk patients are unknown. We randomly assigned 3602 patients with ST-segment elevation myocardial infarction who presented within 12 hours after the onset of symptoms and who were undergoing primary PCI to treatment with heparin plus a glycoprotein IIb/IIIa inhibitor or to treatment with bivalirudin alone. The two primary end points of the study were major bleeding and combined adverse clinical events, defined as the combination of major bleeding or major adverse cardiovascular events, including death, reinfarction, target-vessel revascularization for ischemia, and stroke (hereinafter referred to as net adverse clinical events) within 30 days. Anticoagulation with bivalirudin alone, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, resulted in a reduced 30-day rate of net adverse clinical events (9.2% vs. 12.1%; relative risk, 0.76; 95% confidence interval [CI] 0.63 to 0.92; P=0.005), owing to a lower rate of major bleeding (4.9% vs. 8.3%; relative risk, 0.60; 95% CI, 0.46 to 0.77; P<0.001). There was an increased risk of acute stent thrombosis within 24 hours in the bivalirudin group, but no significant increase was present by 30 days. Treatment with bivalirudin alone, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, resulted in significantly lower 30-day rates of death from cardiac causes (1.8% vs. 2.9%; relative risk, 0.62; 95% CI, 0.40 to 0.95; P=0.03) and death from all causes (2.1% vs. 3.1%; relative risk, 0.66; 95% CI, 0.44 to 1.00; P=0.047). In patients with ST-segment elevation myocardial infarction who are undergoing primary PCI, anticoagulation with bivalirudin alone, as compared with heparin plus glycoprotein IIb/IIIa inhibitors, results in significantly reduced 30-day rates of major bleeding and net adverse clinical events. (ClinicalTrials.gov number, NCT00433966 [ClinicalTrials.gov].). Copyright 2008 Massachusetts Medical Society.
                Bookmark

                Author and article information

                Journal
                Nat Commun
                Nat Commun
                Nature Communications
                Nature Publishing Group
                2041-1723
                30 May 2017
                2017
                : 8
                : 15559
                Affiliations
                [1 ]Case Cardiovascular Research Institute, Case Western Reserve University School of Medicine and Harrington Heart & Vascular Institute, University Hospitals Cleveland Medical Center , Cleveland, Ohio 44106, USA
                [2 ]Department of Medicinal and Biological Chemistry, University of Toledo College of Pharmacy and Pharmaceutical Sciences , Toledo, Ohio 43614, USA
                [3 ]Department of Molecular Cardiology, Cleveland Clinic , Cleveland, Ohio 44106, USA
                [4 ]Bloodworks Northwest Research Institute , Seattle, Washington 98102, USA
                Author notes
                [*]

                Present address: Federal State Scientific Institute, Federal Research Centre Coal and Coal Chemistry, Siberian Branch of the Russian Academy of Sciences, Institute of Human Ecology, 650065 Kemerovo, Russia

                Article
                ncomms15559
                10.1038/ncomms15559
                5477519
                28555620
                3b2a2197-8390-4ae3-ad02-c66d6a9f7fc4
                Copyright © 2017, The Author(s)

                This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

                History
                : 22 August 2016
                : 07 April 2017
                Categories
                Article

                Uncategorized
                Uncategorized

                Comments

                Comment on this article