Search results for "Factor V"
showing 10 items of 146 documents
Recombinant factor VIII: past, present and future of treatment of hemophilia A.
2018
The development of recombinant factor VIII (rFVIII) was initially driven by the necessity to treat hemophilia A (HA) patients with FVIII concentrates without the risk of transmitting infectious agents. Over the last three decades the safety of rFVIII has been further improved by completely removing animal or human proteins from the manufacturing process, so that patients would not be exposed to known or emerging pathogens. Recent efforts have concentrated on improving the expression of rFVIII, reducing its immunogenicity and enhancing its pharmacokinetic (PK) behavior. These new goals have been possible thanks to the develop-ment of biotechnology and a better knowledge of the function and s…
Identification of the integrin-binding site on coagulation factor VIIa required for proangiogenic PAR2 signaling.
2018
The tissue factor (TF) pathway serves both hemostasis and cell signaling, but how cells control these divergent functions of TF remains incompletely understood. TF is the receptor and scaffold of coagulation proteases cleaving protease-activated receptor 2 (PAR2) that plays pivotal roles in angiogenesis and tumor development. Here we demonstrate that coagulation factor VIIa (FVIIa) elicits TF cytoplasmic domain-dependent proangiogenic cell signaling independent of the alternative PAR2 activator matriptase. We identify a Lys-Gly-Glu (KGE) integrin-binding motif in the FVIIa protease domain that is required for association of the TF-FVIIa complex with the active conformer of integrin β1. A po…
Tissue factor at the crossroad of coagulation and cell signaling
2018
The tissue factor (TF) pathway plays a central role in hemostasis and thrombo-inflammatory diseases. Although structure-function relationships of the TF initiation complex are elucidated, new facets of the dynamic regulation of TF?s activities on cells continue to emerge. Cellular pathways that render TF non-coagulant participate in signaling of distinct TF complexes with associated proteases through the protease-activated receptor (PAR) family of G-protein coupled receptors. Additional coreceptors, including the endothelial protein C receptor (EPCR) and integrins, confer signaling specificity by directing subcellular localization and trafficking. We here review how TF is switchedbetween it…
Tissue factor prothrombotic activity is regulated by integrin-arf6 trafficking
2017
Objective— Coagulation initiation by tissue factor (TF) is regulated by cellular inhibitors, cell surface availability of procoagulant phosphatidylserine, and thiol-disulfide exchange. How these mechanisms contribute to keeping TF in a noncoagulant state and to generating prothrombotic TF remain incompletely understood. Approach and Results— Here, we study the activation of TF in primary macrophages by a combination of pharmacological, genetic, and biochemical approaches. We demonstrate that primed macrophages effectively control TF cell surface activity by receptor internalization. After cell injury, ATP signals through the purinergic receptor P2rx7 induce release of TF + microvesicles. T…
Arterial Embolism to the Upper Extremity in a Patient with Factor V Leiden Mutation (APC Resistance)
2003
Factor V Leiden mutation has emerged as one of the leading abnormalities in inherited blood coagulation disorders, resulting in a markedly increased risk for deep leg vein thrombosis. A 24- year-old woman presented with acute onset of critical ischemia of her left thumb and index finger. Intraarterial angiography revealed an embolus in the distal radial artery and a thrombotic occlusion of the digital artery of the thumb and index finger. Immediate therapy encompassed a selective surgical embolectomy of the distal radial artery followed by a local intraarterial lysis that was continued for 3 days. Additionally, therapeutic anticoagulation and vasodilating drugs (prostaglandin E) were admin…
Hemostatic function in young subjects with central obesity: relationship with left ventricular function.
1995
This study was designed to evaluate coagulation and fibrinolysis activity and their relationship with left ventricular function in young obese subjects with central fat distribution. We assessed coagulation and fibrinolysis activity by evaluation of factor VII activity, fibrinogen and plasminogen, plasminogen activator inhibitor (PAI), and tissue plasminogen activator antigen basally (tPA1) and after venous occlusion (tPA2). These measures were evaluated in young (< 40 years) obese subjects with central fat distribution (n = 19) and in comparable lean subjects (n = 20). Blood glucose, triglycerides, total and high-density lipoprotein (HDL) cholesterol, apolipoprotein (apo) A1 and apo B, fas…
PLA1/A2 polymorphism of the platelet glycoprotein receptors IIIA in Behçet's disease
2010
OBJECTIVES: To investigate potential associations between the PlA1/A2 polymorphism of the platelet glycoprotein receptor IIIA (GpIIIa) gene and venous thrombosis and other clinical manifestations in Italian patients with Behçet's disease (BD). METHODS: Two hundred consecutive Italian patients satisfying the International Study Group criteria for BD who were followed up for seven years and 241 healthy Italian age- and gender-matched blood donors were molecularly genotyped for the PlA1/A2 polymorphism of the platelet GpIIIa gene; 118 and 117 of the 200 BD patients were also respectively genotyped for factor V Leiden and prothrombin gene G20210A polymorphisms. A standard microlymphocytotoxicit…
The important impact of dental care on haemostatic treatment burden in patients with mild haemophilia
2022
Background: Mild haemophilia (MH) is mainly characterized by haemorrhages secondary to surgery/invasive procedures or trauma. Haemostatic treatment in MH ranges from on demand to short prophylaxis according to the type of bleeding events and the basal clotting factor level. Oral surgery and dental extractions can represent a frequent haemostatic challenge in MH requiring appropriate treatment. However, only few studies on limited numbers of patients are available in the literature regarding the implications of dental management in patients with MH. Objectives: The purpose of the study was to evaluate the impact of dental care on the burden of haemostatic treatment in patients affected by MH…
New data from the Italian National Register of Congenital Coagulopathies, 2016 Annual Survey
2018
BACKGROUND: In Italy, the National Register of Congenital Coagulopathies (NRCC) collects epidemiological and therapeutic data from patients affected by haemophilia A (HA), haemophilia B (HB), von Willebrand’s disease (vWD) and other rare coagulation disorders. Here we present data from the 2016 annual survey. MATERIALS AND METHODS: Data are provided by the Italian Haemophilia Centres, on a voluntary basis. Information flows from every Centre to a web-based platform of the Italian Association of Haemophilia Centres, shared with the Italian National Institute of Health, in accordance with current privacy laws. Patients are classified by diagnosis, disease severity, age, gender and treatment-r…
Increased frequency of the CTLA-4 49 A/G polymorphism in patients with acquired haemophilia A compared to healthy controls
2007
Acquired haemophilia (AH) is an autoimmune disorder characterized by autoantibodies against endogenous factor VIII (FVIII). Half of the patients present with an underlying disease known to cause the FVIII autoantibodies whereas in the other half the disease is of idiopathic nature. Recently, it has been shown that variants of the polymorphic cytotoxic T lymphocyte antigen-4 (CTLA-4) gene are associated with autoimmune diseases and also represent a risk factor for inhibitor formation in inherited haemophilia A. In the present study, we investigated whether CTLA-4 variants also play a role in the pathogenesis of AH. Therefore, we analyzed three single nucleotide polymorphisms (SNPs) of the CT…