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Toll-like receptors 2 and 7 mediate coagulation activation and coagulopathy in murine sepsis.

ABSTRACT: BACKGROUND:Sepsis is a life-threatening condition often manifested as marked inflammation and severe coagulopathy. Toll-like receptors (TLRs) play a pivotal role in inflammation, organ dysfunction and mortality in animal sepsis. OBJECTIVES:To investigate the role of TLR signaling in mediating sepsis-induced coagulopathy (SIC) in a mouse model. METHODS:Polymicrobial sepsis was created by cecal ligation and puncture (CLP) or fecal slurry peritoneal injection. To quantify global clotting function, two viscoelastic assays were performed with rotational thromboelastometry, and the results were presented as maximum clot firmness (MCF): (a) EXTEM to test tissue factor (TF)-initiated clot formation; and (b) FIBTEM to test EXTEM in the presence of a platelet inhibitor, cytochalasin D. Plasma coagulation factors were quantified with ELISA. TF gene expression and protein expression were determined with real-time quantitative reverse transcription PCR and flow cytometry, respectively. RESULTS:Between 4 and 24 hours after CLP surgery, wild-type mice showed significant MCF reduction in both EXTEM and FIBTEM tests. This was accompanied by marked thrombocytopenia and a significant increase in the levels of plasminogen activator inhibitor-1, plasma TF, and D-dimer. In comparison, TLR2-/- and TLR7-/- CLP mice showed preserved MCF and platelet counts, and near-normal plasma TF levels. Bone marrow-derived macrophages treated with a TLR2 agonist Pam3cys-Ser-(Lys)4 (Pam3cys) or a TLR7 agonist (R837) showed marked increases in TF gene expression and protein expression. MicroRNA-146a, a newly identified proinflammatory mediator that is upregulated during sepsis, induced TF production via a TLR7-dependent mechanism. CONCLUSIONS:Murine sepsis leads to an increased procoagulant response, thrombocytopenia, and global coagulopathy. TLR2 and TLR7 play an important role in procoagulant production and in SIC.

SUBMITTER: Williams B

PROVIDER: S-EPMC7197442 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Toll-like receptors 2 and 7 mediate coagulation activation and coagulopathy in murine sepsis.

Williams Brittney B Neder Jessica J Cui Ping P Suen Andrew A Tanaka Kenichi K Zou Lin L Chao Wei W

Journal of thrombosis and haemostasis : JTH 20190723 10

<h4>Background</h4>Sepsis is a life-threatening condition often manifested as marked inflammation and severe coagulopathy. Toll-like receptors (TLRs) play a pivotal role in inflammation, organ dysfunction and mortality in animal sepsis.<h4>Objectives</h4>To investigate the role of TLR signaling in mediating sepsis-induced coagulopathy (SIC) in a mouse model.<h4>Methods</h4>Polymicrobial sepsis was created by cecal ligation and puncture (CLP) or fecal slurry peritoneal injection. To quantify glob ...[more]

PMID: 31211901

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Project description:OBJECTIVES:To assess the effects of recombinant human soluble thrombomodulin treatment on 28-day all-cause mortality in subgroups categorized by baseline coagulation biomarker levels (prothrombin fragment 1.2, thrombin-antithrombin complex, D-dimer) in patients with sepsis-associated coagulopathy in the Sepsis Coagulopathy Asahi Recombinant LE Thrombomodulin trial (SCARLET) (NCT01598831). DESIGN:Post hoc, subgroup analysis of a randomized, double-blind, placebo-controlled, multinational, multicenter phase 3 study. SETTING:ICUs at 159 sites in 26 countries. PATIENTS:Eight-hundred adults with sepsis-associated coagulopathy defined as international normalized ratio greater than 1.40 and platelet count between 30 × 10/L and 150 × 10/L or greater than 30% decrease within 24 hours with concomitant cardiovascular and/or respiratory failure. INTERVENTIONS:Patients randomized and treated with recombinant human soluble thrombomodulin (0.06 mg/kg/d; n = 395) or equivalent placebo (n = 405) for 6 days. MEASUREMENTS AND MAIN RESULTS:Recombinant human soluble thrombomodulin did not significantly reduce 28-day all-cause mortality in the Sepsis Coagulopathy Asahi Recombinant LE Thrombomodulin trial: absolute risk reduction was 2.55% (p = 0.32) in patients with sepsis-associated coagulopathy. In this post hoc analysis, mortality steadily increased with increasing baseline prothrombin fragment 1.2 and thrombin-antithrombin complex levels in the placebo group; for those values exceeding the upper limit of normal, the mortality increases in the recombinant human soluble thrombomodulin group were lower or negligible with increasing baseline prothrombin fragment 1.2 and thrombin-antithrombin complex. Consequently, absolute risk reductions were greater in subgroups with higher baseline prothrombin fragment 1.2 or thrombin-antithrombin complex. Absolute risk reductions were also greater in subgroups with baseline coagulation biomarker levels at or above median of the entire study population, ranging from 4.2% (95% CI, -5.0% to 13.4%) to 5.5% (95% CI, -4.0% to 14.9%). CONCLUSIONS:Compared with patients receiving placebo, patients treated with recombinant human soluble thrombomodulin having higher baseline thrombin generation biomarker levels had lower mortality. Further research regarding the predictive role of coagulation biomarkers for recombinant human soluble thrombomodulin treatment response in sepsis-associated coagulopathy is warranted to evaluate clinical relevance.

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Dataset Information

Toll-like receptors 2 and 7 mediate coagulation activation and coagulopathy in murine sepsis.

Publications

Toll-like receptors 2 and 7 mediate coagulation activation and coagulopathy in murine sepsis.

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