refludan and Inflammation

Bacterial endotoxins can induce the synthesis and release of vascular endothelial growth factor (VEGF), which may alter vascular permeability and cause vascular leakage.. The effect of acute systemic inflammation on VEGF concentration was measured in healthy males after an intravenous bolus infusion of Escherichia coli endotoxin (lipopolysaccharide, LPS, 20 IU kg-1) in a double-blind, placebo-controlled parallel group study. LPS administration was followed by an infusion of lepirudin (bolus 0.1 mg kg-1, continuous infusion of 0.1 mg kg-1 h-1, n = 12) or saline (n = 12).. Plasma VEGF increased from a mean of 15.1 pg mL-1 to 74.6 pg mL-1 5 h after LPS (P < 0.003). Body temperature, pulse rate, leukcytes, prothrombin fragment 1 + 2 (F1 + 2) and lactoferrin increased and platelets decreased after LPS (P < 0.05). The LPS-induced increase in VEGF was paralleled by the neutrophil cell degranulation marker lactoferrin but not by F1 + 2, and was not affected by lepirudin, which blunted F1 + 2 formation (P < 0.05).. Inflammation-induced activation of leukcytes rather than platelets plays a role in the marked increase in VEGF, which cannot be abrogated by antithrombotic therapy.

Topics: Acute Disease; Adult; Anticoagulants; Blood Coagulation; Blood Platelets; Double-Blind Method; Endothelial Growth Factors; Endotoxins; Escherichia coli; Hirudins; Humans; Inflammation; Intercellular Signaling Peptides and Proteins; Leukocytes; Lymphokines; Male; Recombinant Proteins; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factors

The number of indications for recombinant human hirudin lepirudin therapy has increased in recent years, and now includes acute coronary syndromes and heparin-induced thrombocytopenia. Hence, point of care monitoring appears desirable for therapy with lepirudin. As CoaguChek Plus (CCP) provides a rapid bedside test to monitor therapy with other anticoagulants, we aimed to determine its suitability for lepirudin therapy.. Forty-four healthy volunteers received a 2 ng/kg endotoxin infusion (to induce coagulation) together with clinically relevant doses of lepirudin or heparin in a prospective, placebo-controlled, randomised fashion. Measurements of CCP-partial thromboplastin time (aPTT) were compared to laboratory STA-aPTT.. As expected, baseline values of CCP-aPTT were shorter than STA-aPTT. Lepirudin increased CCP-aPTT 3-fold, and STA-aPTT 2-fold 1 h after bolus infusion. During lepirudin infusion, the correlation between CCP-aPTT and STA-aPTT was excellent (r=0.86-0.92). Both methods were equally sensitive to over-anticoagulation with heparin. Acute systemic inflammation had little effects on CCP-aPTT.. CCP-aPTT is suitable for longitudinal point of care monitoring of lepirudin therapy. As baseline values of CCP-aPTT are shorter than STA-aPTT, it is recommended not to indiscriminately change between methods in the follow-up of individual patients.

Topics: Adult; Anticoagulants; Blood Coagulation; Blood Coagulation Tests; Heparin; Hirudins; Humans; Inflammation; Lipopolysaccharides; Male; Partial Thromboplastin Time; Point-of-Care Systems; Prospective Studies; Recombinant Proteins; Sensitivity and Specificity

Apolipoprotein E (apoE), a component of plasma lipoproteins, increases septic mortality in a rodent model of sepsis, presumably by enhancing lipid antigen presentation to antigen-presenting cells via the low-density lipoprotein receptor (LDLR). Downstream, this culminates in natural killer T (NKT) cell activation and cytokine secretion. To determine whether apoE antagonism would protect against septic mortality in mice, apoE-LDLR binding was antagonized using heparin, which can inhibit apoE's LDLR-binding site.. C57BL/6 mice underwent cecal ligation and puncture (CLP) and heparin infusion. Serum partial thromboplastin time and alanine aminotransferase were measured at 24 hours, and survival was monitored for 7 days after CLP. LDLR+/+ and LDLR-/- fibroblasts were incubated with apoE and heparin to measure apoE internalization. Hepatic NKT cells and cytokine levels were quantified via fluorescence-activated cell sorting.. Heparin decreased CLP-induced mortality by 50% versus saline-treated controls, independent of anticoagulation. LDLR+/+ fibroblasts displayed decreased uptake of apoE when treated concurrently with heparin for 12 hours. In septic mice, hepatic alanine aminotransferase levels, hepatic NKT cells, and plasma cytokine levels decreased after heparin treatment.. This study demonstrates that heparin protects against septic mortality independent of its anticoagulant effect. This protective effect is associated with the inhibition of apoE-LDLR binding, diminished NKT proliferation and cytokine production, and hepatic dysfunction. These findings indicate a potential clinical role for apoE antagonism in the treatment of sepsis.

Topics: Alanine Transaminase; Animals; Anticoagulants; Antigen-Presenting Cells; Apolipoproteins E; Blotting, Western; Cecum; Cytokines; Electrophoresis, Polyacrylamide Gel; Flow Cytometry; Heparin; Hirudins; Inflammation; Ligation; Lymphocyte Activation; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Natural Killer T-Cells; Oligosaccharides; Punctures; Receptors, LDL; Recombinant Proteins

C1-Inhibitor (C1-INH) is an important biological inhibitor, regulating several protein cascade systems. Recent research has shown that the molecule exhibits properties not dependent on its protease inhibition activity. Serum and whole blood from pigs and humans were pre-incubated with C1-INH, iC1-INH or the complement inhibitors SPICE or compstatin. Whole, live Escherichia coli were then added for further incubation. Complement activation, a range of cytokines, chemokines and growth factors, as well as the leukocyte activation markers wCD11R3 (pig) and CD11b (human) were measured. Both C1-INH and iC1-INH dose-dependently and significantly (P<0.05) reduced a range of E. coli-induced pro-inflammatory cytokines and chemokines in porcine and human whole blood, as well as growth factors in human whole blood. Differences between the two forms of C1-INH and between the two species were modest. Most of these anti-inflammatory effects could not be explained by complement inhibition, as specific complement inhibitors had minor effect on several of the mediators. C1-Inhibitor had no inhibitory effect on E. coli-induced complement activation, while iC1-INH enhanced complement activation. The presented data indicate that C1-INH has broad anti-inflammatory effects in E. coli-induced inflammation in pig and human whole blood. These effects are largely independent of the protease inhibition activity.

Topics: Animals; Anti-Inflammatory Agents; Anticoagulants; CD11 Antigens; Chemokines; Complement Activation; Complement C1 Inactivator Proteins; Cytokines; Flow Cytometry; Gram-Negative Bacterial Infections; Hirudins; Humans; Immunoenzyme Techniques; In Vitro Techniques; Indicators and Reagents; Inflammation; Intercellular Signaling Peptides and Proteins; Macrophage Activation; Protease Inhibitors; Recombinant Proteins; Swine

In acute myocardial infarction (AMI), proinflammatory plasma C-reactive protein values are strongly associated with postinfarction morbidity and mortality. So far, the cause of these inflammatory changes is not well understood. Therefore, we sought to investigate the relationship between the activation of coagulation and subsequent systemic inflammatory changes in AMI.. Factor Xa (FXa) bound to tissue factor pathway inhibitor and prothrombin fragments F1+2 (F1+2) were used as a measure for activated coagulation. To assess systemic inflammatory changes, plasma interleukin (IL)-6 and IL-8 concentrations were analyzed by immunoassay. Blood samples were taken from 21 patients with AMI and 20 patients with stable angina pectoris. In AMI, tissue factor pathway inhibitor FXa but not F1+2 plasma levels were associated with circulating IL-8 (P=0.01). In vitro experiments revealed that FXa stimulated IL-8 and monocyte chemoattractant protein-1 release and RNA expression in endothelial cells and mononuclear leukocytes by activation of protease-activated receptor-1.. Our data suggest that coagulation FXa may contribute to proinflammatory changes in AMI by stimulation of IL-8 release. Therapeutic inhibition of the proinflammatory effects of FXa may improve the clinical course in AMI. This study investigates the relationship between the activation of coagulation and systemic inflammatory changes in acute myocardial infarction. Tissue factor pathway inhibitor factor Xa but not F1+2 plasma levels were associated with circulating interleukin-8. In vitro factor Xa stimulated interleukin-8 and monocyte chemoattractant protein-1 release and RNA expression by activation of protease-activated receptor 1 as an underlying mechanism.

Topics: Adult; Aged; Angina Pectoris; Cells, Cultured; Chemokine CCL2; Endothelial Cells; Endothelium, Vascular; Factor Xa; Factor Xa Inhibitors; Female; Hirudins; Humans; Inflammation; Interleukin-6; Interleukin-8; Leukocytes, Mononuclear; Lipoproteins; Male; Middle Aged; Myocardial Infarction; Oligopeptides; Peptide Fragments; Prothrombin; Recombinant Proteins; Umbilical Veins

Meconium aspiration syndrome is a serious condition of the newborn characterized by pulmonary inflammation with substantial neutrophil infiltration. We recently showed that meconium is a potent activator of complement. The aim of the present study was to investigate a possible role for complement in meconium-induced neutrophil activation. Meconium was incubated in human whole blood anticoagulated with lepirudin, a specific thrombin inhibitor that does not affect complement activation. Complement activation was detected by measuring the terminal complement complex. Neutrophil oxidative burst and changes in CD11b and L-selectin expression were measured by flow cytometry. Complement was inhibited using the MAb 166-32 and 137-26, which block factor D and neutralize C5a, respectively. Meconium markedly activated the neutrophils, as revealed by up-regulation of CD11b, accentuation of L-selectin shedding, and induction of oxidative burst. Complement inhibition using the anti-factor D antibody completely (95-100%) blocked meconium-induced changes in CD11b and L-selectin expression, whereas oxidative burst was reduced by 60-70%. The anti-C5a antibody inhibited the neutrophil activation to the same extent as anti-factor D. The data suggest that complement activation is largely responsible for the neutrophil inflammatory responses induced by meconium in vitro and that C5a is a key mediator of this response.

Topics: Antibodies, Monoclonal; CD11b Antigen; Complement Activation; Complement C5a; Complement System Proteins; Dose-Response Relationship, Drug; Flow Cytometry; Hirudins; Humans; Infant, Newborn; Inflammation; L-Selectin; Meconium; Meconium Aspiration Syndrome; Neutrophil Activation; Neutrophils; Oxidative Stress; Protein Binding; Recombinant Proteins; Respiratory Burst; Syndrome