scholarly journals Children with Inflammatory Bowel Disease Exhibit Insensitivity to Tissue Factor Pathway Inhibitor

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2504-2504 ◽  
Author(s):  
Axel Schlagenhauf ◽  
Harald Haidl ◽  
Pohl Sina ◽  
Jahnel Jörg ◽  
Wolfgang Muntean ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Tissue Factor ◽  
Bowel Disease ◽  
Thrombin Generation ◽  
Tissue Factor Pathway Inhibitor ◽  
Conflicts Of Interest ◽  
Lag Time ◽  
Healthy Controls ◽  
Inflammatory Bowel ◽  
Tissue Factor Pathway

Abstract Background: Patients with inflammatory bowel diseases (IBD) exhibit chronic inflammation of the digestive tract associated with a prothrombotic shift in the plasmatic coagulation system as well as heightened platelet reactivity and preactivation. Recently, microbial and platelet-derived inorganic polyphosphate has been shown to inhibit tissue factor pathway inhibitor (TFPI), thus, influencing the hemostatic balance during inflammation. We hypothesized that polyphosphate plays a role in the pathophysiology of inflammatory bowel disease resulting in refractoriness to TFPI activity. Aims: We aimed to determine the hemostatic sensitivity to exogenous TFPI in IBD patients and healthy controls. Methods: Plasma from pediatric patients with active Crohn's disease (CD) (N=10) or ulcerative colitis (UC) (N=10) and age-matched healthy controls (N=20) was spiked with recombinant TFPI (150 ng/ml). Thrombin generation with/without exogenous TFPI was performed using Calibrated Automated Thrombography. Differences in lag time of thrombin generation with/without TFPI were calculated (∆lag time). Results: Without addition of exogenous TFPI, IBD patients exhibited a shorter lag time than controls (IBD: 2.65±0.41 min; Controls: 3.72±0.48 min, P<0.001) Addition of exogenous TFPI prolonged the lag time significantly in healthy controls (∆lag time= 4.69±0.61 min; P<0.001), while the lag time was just slightly prolonged in IBD patients (CD: ∆lag time=0.92±0.37 min; P<0.001; UC: ∆lag time=0.34±27 min; P<0.05). Conclusion: Plasma samples from pediatric IBD patients exhibit refractoriness towards the anticoagulant activity of exogenous TFPI. This hyposensitivity potentially extends to the action of endogenous TFPI which adds to the prothrombotic phenotype associated with IBD. Further studies are needed to determine potential associations with disease activity and the susceptibility to develop thrombosis. Disclosures No relevant conflicts of interest to declare.

scholarly journals A Neutralizing Monoclonal Antibody (PF-06741086) Against Tissue Factor Pathway Inhibitor in Combination with Activated Prothrombin Complex Concentrate Increases Hemostasis in Inhibitor Hemophilia Plasmas without Excessive Thrombin Generation

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 3779-3779
Author(s):  
Swapnil Rakhe ◽  
Sheryl Bowley ◽  
John E. Murphy ◽  
Debra D Pittman
Keyword(s):  
Tissue Factor ◽  
Thrombin Generation ◽  
Tissue Factor Pathway Inhibitor ◽  
Prothrombin Complex Concentrate ◽  
Hemophilia A ◽  
Lag Time ◽  
Hemophilia B ◽  
Activated Prothrombin Complex Concentrate ◽  
Tissue Factor Pathway

Abstract Hemophilia A and B are hereditary bleeding disorders caused by intrinsic coagulation pathway deficiencies of Factor VIII or Factor IX, respectively. Tissue factor pathway inhibitor (TFPI) is a Kunitz-type serine protease inhibitor that negatively regulates thrombin generation within the extrinsic pathway of coagulation. PF-06741086 is a fully human monoclonal antibody which binds the Kunitz-2 domain and neutralizes the inhibitory activity of human tissue factor pathway inhibitor and is currently under development as a potential prophylactic treatment to prevent bleeding episodes in hemophilia A and hemophilia B patients with and without inhibitors. Activated prothrombin complex concentrate (aPCC) is used as bypass treatment for the resolution of bleeding in some hemophilia patients with inhibitors. Hemophilia inhibitor patients receiving PF-06741086 have a possibility to also receive treatment with aPCC. The aim of the current study was to assess the potential additive effect of PF-06741086 with aPCC added in vitro to Hemophilia A and B inhibitor plasmas using a thrombin generation assay (TGA). Thrombin generation in the presence of 1 pM tissue factor and 4 µM phospholipid, was measured using the calibrated automated thrombogram (CAT) system in citrated platelet poor hemophilia A inhibitor (88-160 Bethesda Units) donor plasma or hemophilia B inhibitor (FIX immune-depleted and spiked with FIX neutralizing antibody, 14 Bethesda Units) plasma following the addition of PF-06741086 or aPCC (FEIBA) either alone or in combination. All donors had less than 1% coagulation factor activity. Non-hemophilic plasma from healthy donors alone or spiked in vitro with 16 µg/mL of PF-06741086 was also included in the analysis. Non-hemophilic plasma would have the full complement of coagulation factors. Dose-dependent increases in peak thrombin were observed with the addition of aPCC alone or PF-06741086 alone to the hemophilia plasmas. For combination studies, the aPCC concentration of 1 Unit/mL was selected to correspond to plasma levels that could be achieved clinically post-dosing. The concentration of PF-06741086 at 16µg/mL in these studies was chosen to approximate the Cmax concentration following a single 300 mg subcutaneous dose. Both PF-06741086 (16 µg/mL) and aPCC (1 Unit/mL) decreased the lag time in hemophilia plasma, however, there was not an additive decrease in the lag time with the combination of PF-06741086 and aPCC. The addition of PF-06741086 in combination with aPCC to hemophilia plasma resulted in an increase in thrombin generation including a higher peak thrombin concentration compared to the addition of either alone, but was within the range reported in studies for non-hemophilic normal plasma. To summarize, the addition of aPCC (1 Unit/mL) in combination with PF-06741086 (16µg/mL) in vitro resulted in increased thrombin generation in hemophilia A and hemophilia B inhibitor plasmas without inducing excessive coagulation. Disclosures Rakhe: Pfizer: Employment. Bowley:Pfizer: Employment. Murphy:Pfizer: Employment. Pittman:Pfizer: Employment.

Calibrated automated thrombin generation in paediatric patients with inflammatory bowel disease

2009 ◽  
Vol 29 (S 01) ◽  
pp. S90-S93 ◽  
Author(s):  
H. Bernhard ◽  
A. Deutschmann ◽  
B. Leschnik ◽  
M. Novak ◽  
A. Hauer ◽  
...  
Keyword(s):  
Ulcerative Colitis ◽  
Inflammatory Bowel Disease ◽  
Crohn’S Disease ◽  
Disease Activity ◽  
Bowel Disease ◽  
Thrombin Generation ◽  
Activity Index ◽  
Disease Activity Index ◽  
Healthy Controls ◽  
Inflammatory Bowel

SummaryIn adults, inflammatory bowel disease (IBD) is associated with an increased risk of thromboembolic complications. The pathogenesis of IBD is not really clear and a high thrombin activity might contribute to disease progression. We wanted to see whether children with IBD have a higher thrombin generation (TG). Patients, material, methods: Plasma samples were collected of 20 patients with IBD and of 60 healthy controls (age range from 10 to 19). TG was measured by means of Calibrated automated thrombography (CAT). The disease activity was estimated, using the Pediatric Crohn‘s Disease Activity Index (PCDAI) for Crohn‘s disease and the Pediatric Ulcerative Colitis Disease Activity Index (PUCAI) for Ulcerative Colitis. In addition, we investigated F1+F2, TAT, TFPI and fibrinogen. Results: There was a significant increase of endogenous thrombin potential (ETP), lag time and time to peak in patients with IBD, while peak showed no difference to healthy controls. ETP and F1+F2 in children with IBD also showed a significant correlation with PCDAI (PUCAI) and fibrinogen. Conclusion: IBD in children is associated with high TG, but this seems to be caused mainly by the inflammatory process and not by any individual disposition.

Synergistic Anticoagulant Effect of Activated Protein C and Tissue Factor Pathway Inhibitor As a Mechanism for Acute Traumatic Coagulopathy

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 1487-1487
Author(s):  
Michael A Meledeo ◽  
Melanie V Valenciana ◽  
Armando C Rodriguez ◽  
Andrew P Cap
Keyword(s):  
Synergistic Effect ◽  
Tissue Factor ◽  
Protein C ◽  
Thrombin Generation ◽  
Tissue Factor Pathway Inhibitor ◽  
Activated Protein C ◽  
Lag Time ◽  
Acute Traumatic Coagulopathy ◽  
Tissue Factor Pathway ◽  
Traumatic Coagulopathy

Abstract Introduction Severe trauma with tissue damage and shock can rapidly (<30 min) result in abnormal coagulation function which is independent of consumption or dilution effects; this acute traumatic coagulopathy (ATC) has been linked to increased transfusion requirements, morbidity and mortality. It has been suggested that ATC is caused by an increase in activated protein C (aPC; from 40 pM in normal to 175 pM) which has been identified in trauma patients [Cohen MJ, Ann Surg 255:379 (2012)]. aPC inactivates factor Va (FVa) as part of normal hemostasis, but our previous results indicate that aPC at trauma levels is not sufficient to prevent coagulation, particularly when platelets are present, as platelet fVa is resistant to aPC [Campbell JE, PLoS ONE 9:e99181 (2014); Camire RM, Blood 91:2818 (1998)]. Tissue Factor Pathway Inhibitor (TFPI) is an endothelial-bound protein which inhibits coagulation through effects on factor Xa and the factor VIIa-tissue factor complex. It is released in the plasma (normal level 2.5nM, pathophysiologic states including trauma up to 10nM) and is typically cleared by the liver or kidneys. TFPIα accounts for 20% of circulating TFPI and binds FV and FVa [Ndonwi M, J Thromb Haemost 10:1944 (2012)]. Recently, a truncated FV (termed FV-short) produced by an autosomal dominant mutation was found to form complexes with TFPIα, resulting in retention of TFPIα in a 10-fold increase over normal levels in affected individuals [Vincent LM, J Clin Invest 123:3777 (2013)]. FV-short has significantly reduced thrombogenic potential and, by concomitantly raising TFPIα, causes a bleeding disorder. We hypothesize that the activation of PC in acute trauma may result in the production of FV-degradation products which could stabilize TFPIα similarly to the effect of FV-short. The combination of reduced FVa and increased TFPIα may contribute to ATC. Methods Whole blood from healthy volunteers was drawn by phlebotomy into ACD-containing tubes. Platelet-rich plasma (PRP) and platelet-poor plasma (PPP) were collected by centrifugation (200g for 10 min and 1000g for 15 min, respectively). Calibrated automated thrombogram (CAT) assays and thromboelastography (TEG) were conducted using PRP and PPP with exogenously delivered aPC (0, 100pM, or 1nM) and TFPI (0, 2.5nM, or 10nM). An immunodepleted FV-deficient (<1% normal) plasma (FVdp) was used as a reference. Results CAT assays verified that aPC and TFPI each delay and suppress thrombin generation in PPP in a dose-dependent manner, but the combination of aPC and TFPI had a synergistic effect at the highest doses tested. The endogenous thrombin potential (ETP) was eliminated in PPP (control: 1663 nM-min; 1nM aPC + 10nM TFPI: 0 nM-min; P<0.001); lag time was similarly affected (control: 2.5 min; 1nM aPC + 10nM TFPI: >60 min; P<0.001). FVdp also featured a delayed lag time (11.17 min, P<0.001 versus control), but the delay induced by the addition of 10nM TFPI was not nearly as severe in FVdp (19.67 min) as in the PPP + 10nM aPC sample (>60 min, P<0.001). For PRP, there was no statistical difference between control and the highest doses of aPC and TFPI in ETP (1636 nM-min versus 1388 nM-min) or lag time (8.72 min versus 9.13 min). Conclusions In vitro studies suggest that PC activation is not the sole cause of ATC; the concentrations of aPC measured in trauma patient blood have little effect on the coagulation potential of plasma with or without platelets when aPC is delivered exogenously. The results here demonstrate that there is a synergistic effect between aPC and TFPI. When TFPI is added to FV deficient plasma, the thrombin generation is delayed and suppressed; however, in normal plasma digested with aPC (containing fragmented FVa), the addition of TFPI is sufficient to suppress the generation of thrombin beyond the window of measurement (>60 min). The addition of platelets to the milieu eliminated the effects of aPC, TFPI, and the combination on thrombin generation, highlighting the central role of platelets in maintaining hemostatic function. Disclosures No relevant conflicts of interest to declare.

scholarly journals Procoagulant activity in patients with combined type 2 diabetes and coronary artery disease: No effects of long-term exercise training

2017 ◽  
Vol 14 (2) ◽  
pp. 144-151 ◽  
Author(s):  
Vibeke Bratseth ◽  
Rune Byrkjeland ◽  
Ida U Njerve ◽  
Svein Solheim ◽  
Harald Arnesen ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Exercise Training ◽  
Tissue Factor ◽  
Thrombin Generation ◽  
Tissue Factor Pathway Inhibitor ◽  
Ex Vivo ◽  
Tissue Factor Pathway ◽  
Artery Disease ◽  
Total Tissue

We investigated the effects of 12-month exercise training on hypercoagulability in patients with combined type 2 diabetes mellitus and coronary artery disease. Associations with severity of disease were further explored. Patients ( n = 131) were randomized to exercise training or a control group. Blood was collected at inclusion and after 12 months. Tissue factor, free and total tissue factor pathway inhibitor, prothrombin fragment 1 + 2 (F1 + 2) and D-dimer were determined by enzyme-linked immunosorbent assay and ex vivo thrombin generation by the calibrated automated thrombogram assay. Tissue factor and ex vivo thrombin generation increased from baseline to 12 months ( p < 0.01, all), with no significant differences in changes between groups. At baseline, free and total tissue factor pathway inhibitor significantly correlated to fasting glucose ( p < 0.01, both) and HbA1c ( p < 0.05, both). In patients with albuminuria ( n = 34), these correlations were strengthened, and elevated levels of D-dimer, free and total tissue factor pathway inhibitor ( p < 0.01, all) and decreased ex vivo thrombin generation ( p < 0.05, all) were observed. These results show no effects of exercise training on markers of hypercoagulability in our population with combined type 2 diabetes mellitus and coronary artery disease. The association between poor glycaemic control and tissue factor pathway inhibitor might indicate increased endothelial activation. More pronounced hypercoagulability and increased tissue factor pathway inhibitor were demonstrated in patients with albuminuria.

scholarly journals FOXP3+T Regulatory Cell Modifications in Inflammatory Bowel Disease Patients Treated with Anti-TNFαAgents

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Luisa Guidi ◽  
Carla Felice ◽  
Annabella Procoli ◽  
Giuseppina Bonanno ◽  
Enrica Martinelli ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Inflammatory Bowel Disease ◽  
Flow Cytometry ◽  
Bowel Disease ◽  
Peripheral Blood ◽  
Disease Duration ◽  
Healthy Controls ◽  
T Regulatory Cell ◽  
Inflammatory Bowel ◽  
Necrosis Factor

Treg modulation has been hypothesized as one of the mechanisms by which antitumor necrosis factorα(TNFα) agents exert their action in rheumatoid arthritis (RA) and inflammatory bowel disease (IBD). However, data in IBD are still conflicting. We evaluated CD4+CD25+FOXP3+(Tregs) by flow cytometry in peripheral blood from 32 adult IBD patient before (T0) and after the induction of anti-TNFαtherapy (T1). Eight healthy controls (HCs) were included. We also evaluated the number of FOXP3+cells in the lamina propria (LP) in biopsies taken in a subset of patients and controls. Treg frequencies were significantly increased in peripheral blood from our patients after anti-TNFαtherapy compared to T0. T1 but not T0 levels were higher than HC. The increase was detectable only in clinical responders to the treatment. A negative correlation was found among delta Treg levels and the age of patients or disease duration and with the activity score of Crohn’s disease (CD). No significant differences were found in LP FOXP3+cells. Our data suggest the possibility that in IBD patients the treatment with anti-TNFαmay affect Treg percentages and that Treg modifications may correlate with clinical response, but differently in early versus late disease.

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