24
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: not found

      The neutrophil in vascular inflammation

      review-article
      1 , 2 ,
      Nature Medicine
      Nature Publishing Group US
      Neutrophils, Sepsis, Bacterial infection

      Read this article at

      ScienceOpenPublisherPMC
      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

          Here we focus on how neutrophils have a key regulatory role in vascular inflammation. Recent studies using advanced imaging techniques have yielded new insights into the mechanisms by which neutrophils contribute to defense against bacterial infections and also against sterile injury. In these settings, neutrophils are recruited by various mechanisms depending on the situation. We also describe how these processes may be disrupted in systemic infections, with a particular emphasis on mouse models of sepsis. Neutrophils are often immobilized in the lungs and liver during systemic infections, and this immobilization may be a mechanism through which bacteria can evade the innate immune response or allow neutrophils to form neutrophil extracellular traps that trap and kill bacteria in blood. The platelet is also an important player in sepsis, and we describe how it collaborates with neutrophils in the formation of neutrophil extracellular traps.

          Supplementary information

          The online version of this article (doi:10.1038/nm.2514) contains supplementary material, which is available to authorized users.

          Related collections

          Most cited references69

          • Record: found
          • Abstract: found
          • Article: not found

          Platelet TLR4 activates neutrophil extracellular traps to ensnare bacteria in septic blood.

          It has been known for many years that neutrophils and platelets participate in the pathogenesis of severe sepsis, but the inter-relationship between these players is completely unknown. We report several cellular events that led to enhanced trapping of bacteria in blood vessels: platelet TLR4 detected TLR4 ligands in blood and induced platelet binding to adherent neutrophils. This led to robust neutrophil activation and formation of neutrophil extracellular traps (NETs). Plasma from severely septic humans also induced TLR4-dependent platelet-neutrophil interactions, leading to the production of NETs. The NETs retained their integrity under flow conditions and ensnared bacteria within the vasculature. The entire event occurred primarily in the liver sinusoids and pulmonary capillaries, where NETs have the greatest capacity for bacterial trapping. We propose that platelet TLR4 is a threshold switch for this new bacterial trapping mechanism in severe sepsis.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            A novel mechanism of rapid nuclear neutrophil extracellular trap formation in response to Staphylococcus aureus.

            Neutrophil extracellular traps (NETs) are webs of DNA covered with antimicrobial molecules that constitute a newly described killing mechanism in innate immune defense. Previous publications reported that NETs take up to 3-4 h to form via an oxidant-dependent event that requires lytic death of neutrophils. In this study, we describe neutrophils responding uniquely to Staphylococcus aureus via a novel process of NET formation that did not require neutrophil lysis or even breach of the plasma membrane. The multilobular nucleus rapidly became rounded and condensed. During this process, we observed the separation of the inner and outer nuclear membranes and budding of vesicles, and the separated membranes and vesicles were filled with nuclear DNA. The vesicles were extruded intact into the extracellular space where they ruptured, and the chromatin was released. This entire process occurred via a unique, very rapid (5-60 min), oxidant-independent mechanism. Mitochondrial DNA constituted very little if any of these NETs. They did have a limited amount of proteolytic activity and were able to kill S. aureus. With time, the nuclear envelope ruptured, and DNA filled the cytoplasm presumably for later lytic NET production, but this was distinct from the vesicular release mechanism. Panton-Valentine leukocidin, autolysin, and a lipase were identified in supernatants with NET-inducing activity, but Panton-Valentine leukocidin was the dominant NET inducer. We describe a new mechanism of NET release that is very rapid and contributes to trapping and killing of S. aureus.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              RAGE mediates a novel proinflammatory axis: a central cell surface receptor for S100/calgranulin polypeptides.

              S100/calgranulin polypeptides are present at sites of inflammation, likely released by inflammatory cells targeted to such loci by a range of environmental cues. We report here that receptor for AGE (RAGE) is a central cell surface receptor for EN-RAGE (extracellular newly identified RAGE-binding protein) and related members of the S100/calgranulin superfamily. Interaction of EN-RAGEs with cellular RAGE on endothelium, mononuclear phagocytes, and lymphocytes triggers cellular activation, with generation of key proinflammatory mediators. Blockade of EN-RAGE/RAGE quenches delayed-type hypersensitivity and inflammatory colitis in murine models by arresting activation of central signaling pathways and expression of inflammatory gene mediators. These data highlight a novel paradigm in inflammation and identify roles for EN-RAGEs and RAGE in chronic cellular activation and tissue injury.
                Bookmark

                Author and article information

                Contributors
                pkubes@ucalgary.ca
                Journal
                Nat Med
                Nat. Med
                Nature Medicine
                Nature Publishing Group US (New York )
                1078-8956
                1546-170X
                7 November 2011
                2011
                : 17
                : 11
                : 1381-1390
                Affiliations
                [1 ]GRID grid.8993.b, ISNI 0000 0004 1936 9457, Department of Medical Cell Biology, Division of Integrative Physiology, , Uppsala University, ; Uppsala, Sweden
                [2 ]GRID grid.22072.35, ISNI 0000 0004 1936 7697, Department of Physiology and Pharmacology, , Immunology Research Group, Calvin, Phoebe and Joan Snyder Institute for Infection, Immunity and Inflammation, University of Calgary, ; Calgary, Alberta Canada
                Article
                BFnm2514
                10.1038/nm.2514
                7095830
                22064428
                66e4c7ee-58a5-4a8a-ba61-dd7412eb2e88
                © Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved. 2011

                This article is made available via the PMC Open Access Subset for unrestricted research re-use and secondary analysis in any form or by any means with acknowledgement of the original source. These permissions are granted for the duration of the World Health Organization (WHO) declaration of COVID-19 as a global pandemic.

                History
                Categories
                Article
                Custom metadata
                © The Author(s), under exclusive licence to Springer Nature America, Inc. 2011

                Medicine
                neutrophils,sepsis,bacterial infection
                Medicine
                neutrophils, sepsis, bacterial infection

                Comments

                Comment on this article