scholarly journals Pathogenetic approach to venous thrombosis markers examination

2013 ◽  
Vol 94 (5) ◽  
pp. 685-691 ◽  
Author(s):  
L D Zubairova ◽  
I G Mustafin ◽  
R M Nabiullina

The review summarizes experimental and clinical findings decrypting the mechanisms that initiate venous thrombosis. It is still relevant to consider the pathogenesis of venous thrombosis within the frames of the classic Virchow’s triad, and the mechanisms of interrelation of its separate mechanisms - changes in blood composition, blood flow, or alterations of the blood vessel wall - becomes more clear. Changes in the blood constituents include the amount and functional state of proteins and hemostasis system cells. Among the important changes in blood flow are blood flow rate, affecting the cells and coagulation proteins transport to the site and from the site of thrombosis, and the local shear stress, modulating adhesion and procoagulant activity of endothelium and platelets. Vascular wall provides tissue factor, which is the initiator of blood coagulation; phospholipid surface of cell membranes and microvesicles for assembling coagulation enzyme complexes, as well as adhesion proteins for the blood platelets and leukocytes «capturing». Decreased venous blood outflow and stasis, causing the local hypoxia, are associated with procoagulant changes in blood cells: the expression of P-selectin on endothelium increases, leading to the accumulation of leukocytes and cell microvesicles containing the initiator of blood coagulation - tissue factor. The local concentration of activated clotting factors increases, which along with anticoagulant activity alterations initiates progressing fibrin formation and thrombogenesis. Marking out the key mechanisms allows using them as the potential markers for diagnosing venous thrombosis risk. Among them are cell derived microparticles, cytokines, P-selectin that are investigated as possible indicators of deep vein, pulmonary, cancer associated thrombosis.

Author(s):  
Richard C. Becker ◽  
Frederick A. Spencer

Blood clotting within the venous circulatory system, in contrast to arterial thrombosis, occurs at a relatively slow pace in response to stagnation of flow (stasis) and activation of coagulation. As with arterial thrombosis, vascular injury, either direct in the setting of trauma or indirect as a diffuse, systemic inflammatory response (that ultimately causes endothelial cell damage), represents an important stimulus. Venous thrombi are intravascular deposits composed predominantly of erythrocytes and fibrin, with a variable contribution of platelets and leukocytes. In a majority of cases, thrombosis begins in areas of slow flow within the venous sinuses of valve cusp pockets either in the deep veins of the calf or upper thigh or at sites of direct injury following trauma (Kakkar et al., 1969; Nicolaides et al., 1971). Stasis predisposes to thrombosis most profoundly in the setting of inflammatory states and activated coagulation factors. Slowed blood flow impairs the clearance of coagulation proteases, which through bioamplification increases the local concentration of thrombin substrate. If local thromboresistance is impaired, as may be the case with inherited or acquired thrombophilias (see Chapter 24), thrombosis occurs. Blood flow velocity is reduced by indwelling catheters, which also causes focal endothelial injury, peripheral edema, pregnancy, and valve cusp damage from prior venous thrombosis and/or chronic venous insufficiency (Trottier et al., 1995). Although venous thrombosis can occur in a variety of sites, the most common encountered in clinical practice is within the deep veins of the lower extremity. Thrombi developing within the veins of the calf or thigh can serve as a nidus for growth (propagation), which may cause complete venous obstruction, or embolize to the lungs (pulmonary embolism).


2010 ◽  
Vol 104 (09) ◽  
pp. 514-522 ◽  
Author(s):  
Thomas Lecompte ◽  
Agnès Tournier ◽  
Lise Morlon ◽  
Monique Marchand-Arvier ◽  
Claude Vigneron ◽  
...  

SummaryCathepsin G (Cath G), a serine-protease found in neutrophils, has been reported to have effects that could either facilitate or impede coagulation. Thrombin generation (CAT method) was chosen to study its overall effect on the process, at a plasma concentration (240 nM) observed after neutrophil activation. Coagulation was triggered by tissue factor in the presence of platelets or phospholipid vesicles. To help identify potential targets of Cath G, plasma depleted of clotting factors or of inhibitors was used. Cath G induced a puzzling combination of two diverging effects of varying intensities depending on the phospholipid surface provided: accelerating the process under the three conditions (shortened clotting time by up to 30%), and impeding the process during the same thrombin generation time-course since thrombin peak and ETP (total thrombin potential) were decreased, up to 45% and 12%, respectively, suggestive of deficient prothrombinase. This is consistent with Cath G working on at least two targets in the coagulation cascade. Our data indicate that coagulation acceleration can be attributed neither to platelet activation and nor to activation of a clotting factor. When TFPI (tissue factor pathway inhibitor) was absent, no effect on lag time was observed and the anticoagulant activity of TFPI was decreased in the presence of Cath G. Consistent with the literature and the hypothesis of deficient prothrombinase, experiments using Russel’s Viper Venom indicate that the anticoagulant effect can be attributed to a deleterious effect on factor V. The clinical relevance of these findings deserves to be studied.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1036-1036
Author(s):  
Tetsuhiro Soeda ◽  
Keiji Nogami ◽  
Tomoko Matsumoto ◽  
Kenichi Ogiwara ◽  
Katsumi Nishiya ◽  
...  

Abstract Factor VIIa (FVIIa), complexed with tissue factor (TF), is a trigger of blood coagulation through activation of factor X in the initiation phase. FVIIa can catalyze intrinsic clotting factors such as not only factor IX, but also factor VIII (FVIII). However the role and the mechanisms of the FVIIa-catalyzed FVIII are poorly understood. We first examined FVIIa-catalyzed FVIII activation in the presence of phospholipid (PL) using a one-stage clotting assay. The levels of FVIII activity elevated rapidly by ~4-fold within 30 sec after the addition of FVIIa (1 nM)-TF (1 nM)complex, and subsequently decreased to the initial level within 20 min. This time-dependent reaction was enhanced by the presence of TF and PL in dose-dependent manners, but was moderately inhibited (~50%) in the presence of von Willebrand factor at physiological concentration of 10 μg/mL. FVIII cleavage was evaluated using western blotting immediately after the addition of FVIIa-TF complex. The heavy chain of FVIII was proteolyzed more rapidly (at 15 sec) by cleavages at Arg740 (A2-B junction) and Arg372 (A1-A2 junction) by FVIIa-TF complex, whilst the cleavage at Arg336 in the A1 domain was appeared at ~2.5 min. However little cleavage of the light chain of FVIII was observed, supporting that cleavages at Arg740/Arg372 and Arg336 by FVIIa-TF complex contribute to the up- and down-regulation of FVIII(a) activity, respectively. Of interest, no proteolysis of isolated intact heavy chain was observed, indicating that the proteolysis of the heavy chain was governed by the presence of the light chain. Compared to FVIII activation by thrombin (0.1–1 nM), the activation by FVIIa (0.1–1 nM)-TF (1 nM) complex was observed more rapidly. The activation rate observed by the addition of FVIIa-TF complex was ~50-fold greater than that by thrombin. Kinetics by the chromogenic Xa generation assay showed the catalytic efficiency (kcat/Km; 8.9 min−1/32.8 nM) on FVIIa-TF complex-catalyzed FVIII activation showed ~4-fold greater than that on thrombin-catalyzed activation (kcat/Km; 7.5 min−1/86.4 nM). Furthermore, the catalytic efficiencies on cleavages at Arg740 and Arg372 of FVIII by FVIIa-TF complex were ~3- and ~20-fold greater compared to those by thrombin, respectively. These findings suggested that FVIIa-TF complex was a greater FVIII activator than thrombin in very early phase. In order to localize the binding region for FVIIa, we evaluated the interactions between FVIII subunit and Glu-Gly-Arg-active site modified FVIIa, lacking enzymatic activity, in a surface plasmon resonance-based assay. The heavy chain of FVIII bound to EGR-FVIIa with higher affinity than the light chain (Kd; 2.1 and 45 nM, respectively). Binding was particularly evident with the A2, A3, and C2 domains (Kd; 34, 37, and 44 nM, respectively), whilst the A1 domain failed to bind. In conclusion, we demonstrated that FVIIa-TF complex rapidly activated FVIII by proteolysis of the heavy chain and the activation was governed by the presence of the light chain. Furthermore, present results suggested the role of TF-dependent FVIII activation by FVIIa which is responsible for the initiation phase of blood coagulation.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 3934-3934
Author(s):  
Christian J. Kastrup ◽  
Matthew K. Runyon ◽  
Feng Shen ◽  
Rustem F. Ismagilov

Abstract To investigate the biophysical mechanisms that regulate the spatial dynamics of blood coagulation, we have developed a set of microfluidic tools that allow analysis and perturbation of blood coagulation on the micrometer scale with precise control of fluid flow, geometry, and surface chemistry. Physiological coagulation occurs in a localized manner; specifically, coagulation is believed to occur exclusively at regions of substantial vascular damage and does not spread throughout the entire vascular system. In vitro analysis and characterization of these spatial dynamics requires the ability to reproduce and perturb this system, an ability that is not provided by the mixed reactor systems commonly used for in vitro studies of blood coagulation. We developed microfluidic devices with micrometer-scale channels and methods to coat these channels with various phospholipids, including components of the blood coagulation network such as thrombomodulin and tissue factor, to reproduce in vitro the geometry and surface chemistry of blood vessels in vitro. In a microfluidic device with channels coated with phospholipids and thrombomodulin, we demonstrated that clots propagate in a wave-like fashion with a constant velocity in the absence of flow. We also showed that propagation of coagulation from an occluded channel to a channel with flowing blood plasma can be regulated by the geometry of the junction and the shear rate in the channel with flowing plasma. We also developed microfluidic tools to probe the spatial dynamics of initiation of clotting by patterning surfaces with tissue factor reconstituted into phospholipids bilayers. When human plasma or whole blood was exposed to these surfaces in a microfluidic device, clotting occurred only on patches of tissue factor larger than a threshold size. This threshold patch size is controlled by the rate of activation of clotting factors at the patch and the rate of transport of activated factors off the patch. These results suggest a mechanism for how tissue factor can circulate in blood without causing clotting, and how small regions of vascular damage can exist without causing clotting. These results also suggest new biophysical mechanisms that may control interactions between the coagulation cascade and bacterial surfaces.


1987 ◽  
Author(s):  
M Freund ◽  
J-P Cazenave ◽  
M-L Wiesel ◽  
C Roitsch ◽  
N Riehl-Bellon ◽  
...  

Hirudin (HIR), a polypeptide of 65 aminoacids, is the most potent natural inhibitor of coagulation by forming rapidly a very stable and specific non covalent 1:1 complex with α-thrombin, independent of antithrombin III. Although natural HIR has in vivo anticoagulant and antithrombotic properties, its limited availability for large scale purification has prevented further clinical testing and potential use; this can now be solved by recombinant DNA technology. We have previously reported the cloning and expression of a cDNA encoding one variant (called HV-2) of Hirudo medicinalis HIR (Proc. Natl. Acad. Sci. USA. 1986, 83, 1084-1088). The main factors responsible for venous thrombosis are stasis and thrombin generation secondary to tissue factor liberation from vascular cells and monocytes by injury, endotoxin, interleukin-1 or cachectin and the subsequent activation and circulation of activated clotting factors. We have studied the antithrombotic properties of recombinant HIR, HV-2, in a rat experiemental model of venous thrombosis. HV-2 was expressed in yeast, extracted from culture supernatant and purified by HPLC. Pure HV-2 had an isoleucine NH2-terminus and a specific activity of 13000 ATU/mg.30 male Wistar rats (225-300g) were anesthetized with pentobarbital. At time t (0 min) an i.v. (penis) injection of 0.4 ml of saline or HV-2 (2000 to 8000 ATU/kg) was given, followed at t (5min) by 25 mg/kg tissue factor (Thromboplastin C, Dade) i.v. ; 10 s later stasis of the exposed vena cava between 2 sutures 0.7 cm apart and at t (15 min) removal, blotting, fixation and weighing of the thrombus. Linear regression analysis showed a correlation (r=0.99) between the dose of HV-2 and thrombus weight and a calculated IC50 = 3000 ATU/kg. Total inhibition of thrombus formation was seen after injection of 6000 ATU/kg HV-2 and lasted up to 15 min of circulation, HV-2 being completely eliminated from blood in 60 min and accumulated in the kidneys as shown by gamma imaging with 131I-HV-2. In conclusion, the recombinant HIR HV-2 is a potent immediate antithrombin which inhibits venous thrombosis induced by tissue factor and stasis.


VASA ◽  
2011 ◽  
Vol 40 (2) ◽  
pp. 117-122 ◽  
Author(s):  
Steppich ◽  
Hassenpflug ◽  
Braun ◽  
Schömig ◽  
von Beckerath ◽  
...  

Background: Circulating Tissue Factor (TF) is associated with inflammation and may contribute to thrombotic events. Aim of this study was to analyze circulating TF activity and proinflammatory cytokines in patients with deep venous thrombosis. Patients and methods: Forty-eight patients with deep vein thrombosis and 45 control subjects were included. Venous blood samples were obtained at diagnosis for analysis of TF activity, TF antigen, prothrombin fragment F1 + 2, microparticles (expressing phosphatidylserine and supporting FXa generation), Interleukin (IL)-1beta, IL-6, IL-8, IL-10, IL-12 and Tumor-Necrosis-Factor-alpha (TNF). Results: TF antigen, activity and microparticles were similar in both groups: In contrast, a significant increase in plasma IL-6, IL-8 and F1 + 2 levels was found in thrombosis. This increase in IL-6 and IL-8 as well as F1 + 2 was not correlated with the extent of thrombosis, predisposing factors or onset of symptoms. Conclusions: Circulating TF and microparticles are not elevated in deep venous thrombosis. The increase in IL-6, IL-8 and F1 + 2 during thrombosis was not proportional to the extent or predisposing risk factors.


2013 ◽  
Vol 1 (2) ◽  
pp. 126-133 ◽  
Author(s):  
Kevin Caldwell ◽  
Steven J. Prior ◽  
Meghan Kampmann ◽  
Limin Zhao ◽  
Sue McEvoy ◽  
...  

Blood ◽  
1990 ◽  
Vol 76 (6) ◽  
pp. 1158-1164 ◽  
Author(s):  
HJ Hassan ◽  
A Leonardi ◽  
C Chelucci ◽  
G Mattia ◽  
G Macioce ◽  
...  

Abstract The expression of a number of blood coagulation factors (F) (FX, FIX, FVIII, FVII, alpha-, beta-, gamma-fibrinogen chains, protein C, and antithrombin III [AT III]) was analyzed at RNA and protein level in 5- to 10-week-old human embryos and fetuses. FX, FIX, and FVII were also analyzed at protein level. Total and poly(A)+ RNA, extracted from embryonic-fetal (FL) and adult liver (AL), were analyzed by dot and Northern blot hybridization with specific cDNA probes. The results indicate that: (1) the size of the messenger RNAs of these factors is equivalent in FL and AL; (2) in the 5- to 10-week period, their abundance in FL increases from 30% to 50% of the adult level except for FIX (from 2% to 10%) and FX (always 100% of the adult value). Western blot analysis of FIX, FX, and FVII in 5- to 10-week soluble liver proteins and 6- to 8-week plasma showed a low level of FIX versus a higher concentration of both FVII and FX, when compared with corresponding adult values, ie, a liver protein level of 10% versus 100% and a plasma concentration level of 10% versus 40%. Although little is known so far on the activity and the functional role of the clotting factors in early human ontogenic development, these studies suggest an activation of FX via the FVII/tissue factor activity rather than the FIXa/FVIIIa phospholipid complex in human embryonic and early fetal life.


2015 ◽  
Vol 30 (1_suppl) ◽  
pp. 7-13 ◽  
Author(s):  
DD Myers

In this chapter, an overview of some of the prominent risk factors that contribute to the pathophysiology of venous thrombosis will be discussed. In 1856, Dr Rudolf Virchow developed the concept outlining the genesis of intravascular thrombosis. Dr Virchow hypothesized that circulatory stasis due to interrupted blood flow, changes in the blood leading to blood coagulation, and irritation or damage to the vascular endothelium would initiate acute venous thrombus generation. Presently, it is known that these above-mentioned risk factors are influenced by increasing age, gender, and obesity. The current chapter will focus on recent preclinical and clinical investigations that will give the reader insight into the prothrombotic mechanisms that lead to acute venous thrombosis.


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