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Florova G, Azghani AO, Karandashova S, Schaefer C, Yarovoi SV, Declerck PJ, Cines DB, Idell S, Komissarov AA. Targeting plasminogen activator inhibitor-1 in tetracycline-induced pleural injury in rabbits. Am J Physiol Lung Cell Mol Physiol 2017; 314:L54-L68. [PMID: 28860148 DOI: 10.1152/ajplung.00579.2016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Elevated active plasminogen activator inhibitor-1 (PAI-1) has an adverse effect on the outcomes of intrapleural fibrinolytic therapy (IPFT) in tetracycline-induced pleural injury in rabbits. To enhance IPFT with prourokinase (scuPA), two mechanistically distinct approaches to targeting PAI-1 were tested: slowing its reaction with urokinase (uPA) and monoclonal antibody (mAb)-mediated PAI-1 inactivation. Removing positively charged residues at the "PAI-1 docking site" (179RHRGGS184→179AAAAAA184) of uPA results in a 60-fold decrease in the rate of inhibition by PAI-1. Mutant prourokinase (0.0625-0.5 mg/kg; n = 12) showed efficacy comparable to wild-type scuPA and did not change IPFT outcomes ( P > 0.05). Notably, the rate of PAI-1-independent intrapleural inactivation of mutant uPA was 2 times higher ( P < 0.05) than that of the wild-type enzyme. Trapping PAI-1 in a "molecular sandwich"-type complex with catalytically inactive two-chain urokinase with Ser195Ala substitution (S195A-tcuPA; 0.1 and 0.5 mg/kg) did not improve the efficacy of IPFT with scuPA (0.0625-0.5 mg/kg; n = 11). IPFT failed in the presence of MA-56A7C10 (0.5 mg/kg; n = 2), which forms a stable intrapleural molecular sandwich complex, allowing active PAI-1 to accumulate by blocking its transition to a latent form. In contrast, inactivation of PAI-1 by accelerating the active-to-latent transition mediated by mAb MA-33B8 (0.5 mg/kg; n = 2) improved the efficacy of IPFT with scuPA (0.25 mg/kg). Thus, under conditions of slow (4-8 h) fibrinolysis in tetracycline-induced pleural injury in rabbits, only the inactivation of PAI-1, but not a decrease in the rate of its reaction with uPA, enhances IPFT. Therefore the rate of fibrinolysis, which varies in different pathologic states, could affect the selection of PAI-1 inhibitors to enhance fibrinolytic therapy.
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Affiliation(s)
- Galina Florova
- Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Ali O Azghani
- Department of Biology, The University of Texas at Tyler, Tyler, Texas
| | - Sophia Karandashova
- Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Chris Schaefer
- Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Serge V Yarovoi
- Department of Pathology and Laboratory Medicine, Perelman-University of Pennsylvania School of Medicine , Philadelphia, Pennsylvania
| | - Paul J Declerck
- Laboratory for Therapeutic and Diagnostic Antibodies, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Leuven , Belgium
| | - Douglas B Cines
- Department of Pathology and Laboratory Medicine, Perelman-University of Pennsylvania School of Medicine , Philadelphia, Pennsylvania
| | - Steven Idell
- Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler , Tyler, Texas
| | - Andrey A Komissarov
- Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler , Tyler, Texas
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Florova G, Azghani A, Karandashova S, Schaefer C, Koenig K, Stewart-Evans K, Declerck PJ, Idell S, Komissarov AA. Targeting of plasminogen activator inhibitor 1 improves fibrinolytic therapy for tetracycline-induced pleural injury in rabbits. Am J Respir Cell Mol Biol 2016; 52:429-37. [PMID: 25140386 DOI: 10.1165/rcmb.2014-0168oc] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Endogenous active plasminogen activator inhibitor 1 (PAI-1) was targeted in vivo with monoclonal antibodies (mAbs) that redirect its reaction with proteinases to the substrate branch. mAbs were used as an adjunct to prourokinase (single-chain [sc] urokinase [uPA]) intrapleural fibrinolytic therapy (IPFT) of tetracycline-induced pleural injury in rabbits. Outcomes of scuPA IPFT (0.25 or 0.0625 mg/kg) with 0.5 mg/kg of mouse IgG or mAbs (MA-33H1F7 and MA-8H9D4) were assessed at 24 hours. Pleural fluid (PF) was collected at 0, 10, 20, and 40 minutes and 24 hours after IPFT and analyzed for plasminogen activating (PA), uPA, fibrinolytic activities, levels of total plasmin/plasminogen, α-macroglobulin (αM), mAbs/IgG antigens, free active uPA, and αM/uPA complexes. Anti-PAI-1 mAbs, but not mouse IgG, delivered with an eightfold reduction in the minimal effective dose of scuPA (from 0.5 to 0.0625 mg/kg), improved the outcome of IPFT (P < 0.05). mAbs and IgG were detectable in PFs at 24 hours. Compared with identical doses of scuPA alone or with IgG, treatment with scuPA and anti-PAI-1 mAbs generated higher PF uPA amidolytic and PA activities, faster formation of αM/uPA complexes, and slower uPA inactivation. However, PAI-1 targeting did not significantly affect intrapleural fibrinolytic activity or levels of total plasmin/plasminogen and αM antigens. Targeting PAI-1 did not induce bleeding, and rendered otherwise ineffective doses of scuPA able to improve outcomes in tetracycline-induced pleural injury. PAI-1-neutralizing mAbs improved IPFT by increasing the durability of intrapleural PA activity. These results suggest a novel, well-tolerated IPFT strategy that is tractable for clinical development.
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Affiliation(s)
- Galina Florova
- 1 Texas Lung Injury Institute of the University of Texas Health Science Center at Tyler, Tyler, Texas
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Komissarov AA, Florova G, Azghani AO, Buchanan A, Bradley WM, Schaefer C, Koenig K, Idell S. The time course of resolution of adhesions during fibrinolytic therapy in tetracycline-induced pleural injury in rabbits. Am J Physiol Lung Cell Mol Physiol 2015; 309:L562-72. [PMID: 26163512 DOI: 10.1152/ajplung.00136.2015] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 07/02/2015] [Indexed: 11/22/2022] Open
Abstract
The time required for the effective clearance of pleural adhesions/organization after intrapleural fibrinolytic therapy (IPFT) is unknown. Chest ultrasonography and computed tomography (CT) were used to assess the efficacy of IPFT in a rabbit model of tetracycline-induced pleural injury, treated with single-chain (sc) urokinase plasminogen activators (scuPAs) or tissue PAs (sctPA). IPFT with sctPA (0.145 mg/kg; n = 10) and scuPA (0.5 mg/kg; n = 12) was monitored by serial ultrasonography alone (n = 12) or alongside CT scanning (n = 10). IPFT efficacy was assessed with gross lung injury scores (GLIS) and ultrasonography scores (USS). Pleural fluids withdrawn at 0-240 min and 24 h after IPFT were assayed for PA and fibrinolytic activities, α-macroglobulin/fibrinolysin complexes, and active PA inhibitor 1 (PAI-1). scuPA and sctPA generated comparable steady-state fibrinolytic activities by 20 min. PA activity in the scuPA group decreased slower than the sctPA group (kobs = 0.016 and 0.042 min(-1)). Significant amounts of bioactive uPA/α-macroglobulin (but not tPA; P < 0.05) complexes accumulated at 0-40 min after IPFT. Despite the differences in intrapleural processing, IPFT with either fibrinolysin was effective (GLIS ≤ 10) in animals imaged with ultrasonography only. USS correlated well with postmortem GLIS (r(2) = 0.85) and confirmed relatively slow intrapleural fibrinolysis after IPFT, which coincided with effective clearance of adhesions/organization at 4-8 h. CT scanning was associated with less effective (GLIS > 10) IPFT and higher levels of active PAI-1 at 24 h following therapy. We concluded that intrapleural fibrinolysis in tetracycline-induced pleural injury in rabbits is relatively slow (4-8 h). In CT-scanned animals, elevated PAI-1 activity (possibly radiation induced) reduced the efficacy of IPFT, buttressing the major impact of active PAI-1 on IPFT outcomes.
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Affiliation(s)
- Andrey A Komissarov
- The Department of Cellular and Molecular Biology and the Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler (UTHSCT), Tyler, Texas;
| | - Galina Florova
- The Department of Cellular and Molecular Biology and the Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler (UTHSCT), Tyler, Texas
| | - Ali O Azghani
- The Department of Biology at the University of Texas at Tyler, Tyler, Texas
| | - Ann Buchanan
- UTHSCT Vivarium, The University of Texas Health Science Center at Tyler, Tyler, Texas
| | - William M Bradley
- The Department of Radiation Oncology, The University of Texas Health Science Center at Tyler, Tyler, Texas
| | - Chris Schaefer
- The Department of Cellular and Molecular Biology and the Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler (UTHSCT), Tyler, Texas
| | - Kathleen Koenig
- The Department of Cellular and Molecular Biology and the Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler (UTHSCT), Tyler, Texas
| | - Steven Idell
- The Department of Cellular and Molecular Biology and the Texas Lung Injury Institute, The University of Texas Health Science Center at Tyler (UTHSCT), Tyler, Texas
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Gupta KK, Donahue DL, Sandoval-Cooper MJ, Castellino FJ, Ploplis VA. Abrogation of plasminogen activator inhibitor-1-vitronectin interaction ameliorates acute kidney injury in murine endotoxemia. PLoS One 2015; 10:e0120728. [PMID: 25799354 PMCID: PMC4370643 DOI: 10.1371/journal.pone.0120728] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 02/06/2015] [Indexed: 01/20/2023] Open
Abstract
Sepsis-induced acute kidney injury (AKI) contributes to the high mortality and morbidity in patients. Although the pathogenesis of AKI during sepsis is poorly understood, it is well accepted that plasminogen activator inhibitor-1 (PAI-1) and vitronectin (Vn) are involved in AKI. However, the functional cooperation between PAI-1 and Vn in septic AKI has not been completely elucidated. To address this issue, mice were utilized lacking either PAI-1 (PAI-1−/−) or expressing a PAI-1-mutant (PAI-1R101A/Q123K) in which the interaction between PAI-1 and Vn is abrogated, while other functions of PAI-1 are retained. It was found that both PAI-1−/− and PAI-1R101A/Q123K mice are associated with decreased renal dysfunction, apoptosis, inflammation, and ERK activation as compared to wild-type (WT) mice after LPS challenge. Also, PAI-1−/− mice showed attenuated fibrin deposition in the kidneys. Furthermore, a lack of PAI-1 or PAI-1-Vn interaction was found to be associated with an increase in activated Protein C (aPC) in plasma. These results demonstrate that PAI-1, through its interaction with Vn, exerts multiple deleterious mechanisms to induce AKI. Therefore, targeting of the PAI-1-Vn interaction in kidney represents an appealing therapeutic strategy for the treatment of septic AKI by not only altering the fibrinolytic capacity but also regulating PC activity.
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Affiliation(s)
- Kamlesh K Gupta
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Deborah L Donahue
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Mayra J Sandoval-Cooper
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Francis J Castellino
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, United States of America; Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, United States of America
| | - Victoria A Ploplis
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana, United States of America; Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana, United States of America
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Cap A, Hunt BJ. The pathogenesis of traumatic coagulopathy. Anaesthesia 2015; 70 Suppl 1:96-101, e32-4. [PMID: 25440402 DOI: 10.1111/anae.12914] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/19/2014] [Indexed: 12/14/2022]
Abstract
Over the last 10 years, the management of major haemorrhage in trauma patients has changed radically. This is mainly due to the recognition that many patients who are bleeding when they come in to the emergency department have an established coagulopathy before the haemodilution effects of fluid resuscitation. This has led to the use of new terminology: acute traumatic coagulopathy, acute coagulopathy of trauma shock or trauma-induced coagulopathy. The recognition of acute traumatic coagulopathy is important, because we now understand that its presence is a prognostic indicator, as it is associated with poor clinical outcome. This has driven a change in clinical management, so that the previous approach of maintaining an adequate circulating volume and oxygen carrying capacity before, as a secondary event, dealing with coagulopathy, has changed to haemostatic resuscitation as early as possible. While there is as yet no universally accepted assay or definition, many experts use prolongation of the prothrombin time to indicate that there is, indeed, a coagulopathy. Hypoxia, acidosis and hypothermia and hormonal, immunological and cytokine production, alongside consumption and blood loss, and the dilutional effects of resuscitation may occur to varying extents depending on the type of tissue damaged, the type and extent of injury, predisposing to, or amplifying, activation of coagulation, platelets, fibrinolysis. These are discussed in detail within the article.
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Affiliation(s)
- A Cap
- Uniformed Services University, Blood Research Program, US Army Institute of Surgical Research, Sam Houston, Texas, USA
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Comparative response of platelet fV and plasma fV to activated protein C and relevance to a model of acute traumatic coagulopathy. PLoS One 2014; 9:e99181. [PMID: 24921658 PMCID: PMC4055642 DOI: 10.1371/journal.pone.0099181] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Accepted: 05/12/2014] [Indexed: 12/31/2022] Open
Abstract
Background Acute traumatic coagulopathy (ATC) has been linked to an increase in activated protein C (aPC) from 40 pM in healthy individuals to 175 pM. aPC exerts its activity primarily through cleavage of active coagulation factor Va (fVa). Platelets reportedly possess fVa which is more resistant to aPC cleavage than plasma fVa; this work examines the hypothesis that normal platelets are sufficient to maintain coagulation in the presence of elevated aPC. Methods Coagulation responses of normal plasma, fV deficient plasma (fVdp), and isolated normal platelets in fVdp were conducted: prothrombin (PT) tests, turbidimetry, and thromboelastography (TEG), including the dose response of aPC on the samples. Results PT and turbidimetric assays demonstrate that normal plasma is resistant to aPC at doses much higher than those found in ATC. Additionally, an average physiological number of washed normal platelets (200,000 platelets/mm3) was sufficient to eliminate the anti-coagulant effects of aPC up to 10 nM, nearly two orders of magnitude above the ATC concentration and even the steady-state pharmacological concentration of human recombinant aPC, as measured by TEG. aPC also demonstrated no significant effect on clot lysis in normal plasma samples with or without platelets. Conclusions Although platelet fVa shows slightly superior resistance to aPC's effects compared to plasma fVa in static models, neither fVa is sufficiently cleaved in simulations of ATC or pharmacologically-delivered aPC to diminish coagulation parameters. aPC is likely a correlative indicator of ATC or may play a cooperative role with other activity altering products generated in ATC.
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Florova G, Karandashova S, Declerck PJ, Idell S, Komissarov AA. Remarkable stabilization of plasminogen activator inhibitor 1 in a "molecular sandwich" complex. Biochemistry 2013; 52:4697-709. [PMID: 23734661 DOI: 10.1021/bi400470s] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Plasminogen activator inhibitor 1 (PAI-1) levels are elevated in a number of life-threatening conditions and often correlate with unfavorable outcomes. Spontaneous inactivation due to active to latent transition limits PAI-1 activity in vivo. While endogenous vitronectin (Vn) stabilizes PAI-1 by 1.5-2.0-fold, further stabilization occurs in a "molecular sandwich" complex (MSC) in which a ligand that restricts the exposed reactive center loop is bound to PAI-1/Vn. The effects of S195A two-chain urokinase (tcuPA) and Vn on inactivation of wild-type (wt) glycosylated (Gl-PAI-1), nonglycosylated (rPAI-1), and nonglycosylated Q123K PAI-1 (lacks Vn binding) forms were studied. S195A tcuPA decreased the rate constant (kL) for spontaneous inactivation at 37 °C for rPAI-1, Q123K, and Gl-PAI-1 by 6.7-, 3.4-, and 7.8-fold, respectively, and both S195A tcuPA and Vn by 66.7-, 5.5-, and 103.3-fold, respectively. Analysis of the temperature dependences of kL revealed a synergistic increase in the Gibbs free activation energy for spontaneous inactivation of wt Gl-PAI-1 and rPAI-1 in MSC from 99.8 and 96.1 to 111.3 and 107.0 kJ/mol, respectively, due to an increase in the activation enthalpy and a decrease in the activation entropy. Anti-PAI-1 monoclonal antibodies (mAbs) competing with proteinase also stabilize PAI-1/Vn. The rate of inhibition of target proteinases by MSCs, with a stoichiometry close to unity, was limited by the dissociation (k = 10(-4) to 10(-3) s(-1)) of S195A tcuPA or mAb. The stabilization of PAI-1 in MSCs in vivo may potentiate uncontrolled thrombosis or extravascular fibrin deposition, suggesting a new paradigm for using PAI-1 inhibitors and novel potential targets for therapy.
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Affiliation(s)
- Galina Florova
- Texas Lung Injury Institute, University of Texas Health Science Center at Tyler , 11937 U.S. Highway 271, Tyler, Texas 75708-3154, United States
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Karandashova S, Florova G, Azghani AO, Komissarov AA, Koenig K, Tucker TA, Allen TC, Stewart K, Tvinnereim A, Idell S. Intrapleural adenoviral delivery of human plasminogen activator inhibitor-1 exacerbates tetracycline-induced pleural injury in rabbits. Am J Respir Cell Mol Biol 2012; 48:44-52. [PMID: 23002099 DOI: 10.1165/rcmb.2012-0183oc] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Elevated concentrations of plasminogen activator inhibitor-1 (PAI-1) are associated with pleural injury, but its effects on pleural organization remain unclear. A method of adenovirus-mediated delivery of genes of interest (expressed under a cytomegalovirus promoter) to rabbit pleura was developed and used with lacZ and human (h) PAI-1. Histology, β-galactosidase staining, Western blotting, enzymatic and immunohistochemical analyses of pleural fluids (PFs), lavages, and pleural mesothelial cells were used to evaluate the efficiency and effects of transduction. Transduction was selective and limited to the pleural mesothelial monolayer. The intrapleural expression of both genes was transient, with their peak expression at 4 to 5 days. On Day 5, hPAI-1 (40-80 and 200-400 nM of active and total hPAI-1 in lavages, respectively) caused no overt pleural injury, effusions, or fibrosis. The adenovirus-mediated delivery of hPAI-1 with subsequent tetracycline-induced pleural injury resulted in a significant exacerbation of the pleural fibrosis observed on Day 5 (P = 0.029 and P = 0.021 versus vehicle and adenoviral control samples, respectively). Intrapleural fibrinolytic therapy (IPFT) with plasminogen activators was effective in both animals overexpressing hPAI-1 and control animals with tetracycline injury alone. An increase in intrapleural active PAI-1 (from 10-15 nM in control animals to 20-40 nM in hPAI-1-overexpressing animals) resulted in the increased formation of PAI-1/plasminogen activator complexes in vivo. The decrease in intrapleural plasminogen-activating activity observed at 10 to 40 minutes after IPFT correlates linearly with the initial concentration of active PAI-1. Therefore, active PAI-1 in PFs affects the outcome of IPFT, and may be both a biomarker of pleural injury and a molecular target for its treatment.
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Affiliation(s)
- Sophia Karandashova
- Texas Lung Injury Institute, University of Texas Health Science Center at Tyler, Tyler, TX 75708, USA
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Scaldaferri F, Lancellotti S, Pizzoferrato M, Cristofaro RD. Haemostatic system in inflammatory bowel diseases: New players in gut inflammation. World J Gastroenterol 2011; 17:594-608. [PMID: 21350708 PMCID: PMC3040331 DOI: 10.3748/wjg.v17.i5.594] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2010] [Revised: 03/25/2010] [Accepted: 04/01/2010] [Indexed: 02/06/2023] Open
Abstract
Inflammation and coagulation constantly influence each other and are constantly in balance. Emerging evidence supports this statement in acute inflammatory diseases, such as sepsis, but it also seems to be very important in chronic inflammatory settings, such as inflammatory bowel disease (IBD). Patients with Crohn’s disease and ulcerative colitis have an increased risk of thromboembolic events, and several abnormalities concerning coagulation components occur in the endothelial cells of intestinal vessels, where most severe inflammatory abnormalities occur. The aims of this review are to update and classify the type of coagulation system abnormalities in IBD, and analyze the strict and delicate balance between coagulation and inflammation at the mucosal level. Recent studies on possible therapeutic applications arising from investigations on coagulation abnormalities associated with IBD pathogenesis will also be briefly presented and critically reviewed.
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Abstract
OBJECTIVE To review new findings about the function of the protein C system during inflammation and coagulation. MAIN FINDINGS Coagulation proteases and their cofactors modify the outcome of severe inflammation by engaging signaling-competent cell surface receptors. The central effector protease of the protein C pathway, activated protein C, interacts with the endothelial cell protein C receptor, protease-activated receptors, and other receptors to exert multiple effects on hemostasis and immune cell function. Thrombomodulin controls the complement arm of the innate immune system in a thrombin-dependent manner through activation of the thrombin activatable inhibitor of fibrinolysis, and in a thrombin-independent, constitutive manner via its lectin-like extracellular domain; and inhibits the inflammatory effects of high-mobility box group 1 protein. Protein S not only suppresses coagulation as an enhancing cofactor for the coagulation inhibitors activated protein C and tissue factor pathway inhibitor but also is also a physiologic ligand for the Tyro/axl/Mer-family of receptor tyrosine kinases that mediate an anti-inflammatory regulatory loop of dendritic cell and monocyte inflammatory function. CONCLUSIONS The immune-regulatory capacity of the protein C pathway and its individual components emerge as the dominant action of this pathway in the setting of severe inflammation.
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