APC Resistance and other Haemostatic Variables during Pregnancy and Puerperium

1999 ◽  
Vol 81 (04) ◽  
pp. 527-531 ◽  
Author(s):  
U. Kjellberg ◽  
N.-E. Andersson ◽  
S. Rosén ◽  
L. Tengborn ◽  
M. Hellgren
Keyword(s):  
Factor Viii ◽  
Plasminogen Activator ◽  
Protein C ◽  
Activated Protein C ◽  
Plasminogen Activator Inhibitor ◽  
Protein S ◽  
Reference Level ◽  
Soluble Fibrin ◽  
Prothrombin Fragment ◽  
D Dimer

SummaryForty-eight healthy pregnant women were studied prospectively and longitudinally. Blood sampling was performed at 10-15, 23-25, 32-34 and 38-40 weeks of gestation, within one week and at eight weeks postpartum. Classic and modified activated protein C ratio decreased as pregnancy progressed. In the third trimester 92% of the ratios measured with the classic test were above the lower reference level whereas all modified test ratios were normal. Slight activation of blood coagulation was shown with increased levels of prothrombin fragment 1+2, soluble fibrin and D-dimer. Fibrinogen, factor VIII and plasminogen activator inhibitor type 1 and type 2 increased. Protein S and tissue plasminogen activator activity decreased. Protein C remained unchanged. No correlation was found between the decrease in classic APC ratio and changes in factor VIII, fibrinogen, protein S, prothrombin fragment 1+2 or soluble fibrin, nor between the increase in soluble fibrin and changes in prothrombin fragment 1+2, fibrinogen and D-dimer.

scholarly journals The role of hypercoagulability in the development of osteonecrosis of the femoral head

2012 ◽  
Vol 4 (2) ◽  
pp. 17 ◽  
Author(s):  
Marios G. Lykissas ◽  
Ioannis P. Kostas-Agnantis ◽  
Ioannis D. Gelalis ◽  
Georgios Vozonelos ◽  
Anastasios V. Korompilias
Keyword(s):  
Plasminogen Activator ◽  
Lupus Erythematosus ◽  
Protein C ◽  
Activated Protein C ◽  
Plasminogen Activator Inhibitor ◽  
Protein S ◽  
Intravascular Coagulation ◽  
S Deficiency ◽  
Increased Risk ◽  
Von Willebrand

Despite the large number of the outstanding researches, pathogenesis of osteonecrosis remains unknown. During the last decades the hypothesis that increased intravascular coagulation may be the pathogenetic mechanism which leads to osteonecrosis is gaining constantly support. Both primary factors of hypercoagulability, such as resistance to activated protein C, protein C and protein S deficiency, low levels of tissue plasminogen activator, high levels of plasminogen activator inhibitor, von Willebrand factor, lipoprotein (a), and secondary factors of hypercoagulability with factors potentially activating intravascular coagulation, such as pregnancy, antiphospholipid antibodies, systemic lupus erythematosus, hemoglobinopathies and sickle cell disease, and hemato-oncologic diseases are discussed in this article. Although coagulation abnormalities in patients with hip osteonecrosis might represent increased risk factors for the development of bone necrosis by predisposing the patient to thromboembolic phenomena, further investigation is needed to indicate the definite correlation between factors leading to increased intravascular coagulation and pathogenesis of osteonecrosis.

Activated Protein C Increases Fibrin Clot Lysis by Neutralization of Plasminogen Activator Inhibitor No Evidence for a Cofactor Role of Protein S

1988 ◽  
Vol 60 (02) ◽  
pp. 328-333 ◽  
Author(s):  
N J de Fouw ◽  
Y F de Jong ◽  
F Haverkate ◽  
R M Bertina
Keyword(s):  
Plasminogen Activator ◽  
Protein C ◽  
Blood Platelets ◽  
Plasminogen Activator Inhibitor ◽  
Protein S ◽  
Tissue Type ◽  
Clot Lysis ◽  
Activator Inhibitor ◽  
Pai 1

summaryThe effect of purified human activated protein G (APC) on fibrinolysis was studied using a clot iysis system consisting of purified glu-plasminogen, tissue-type plasminogen activator, plasminogen activator inhibitor (released from endothelial cells or blood platelets), fibrinogen, 125T-fibrinogen and thrombin. All proteins were of human origin.In this system APC could increase fibrinolysis in a dose dependent way, without affecting fibrin formation or fibrin crosslinking. However, this profibrinolytic effect of APC could only be observed when plasminogen activator inhibitor (PAI-l) was present. The effect of APC was completely quenched by pretreatment of APC with anti-protein C IgG or di-isopropylfluorophosphate. Addition of the cofactors of APC:protein S, Ca2+-ions and phospholipid-alone or in combination did not enhance the profibrinolytic effect of APC. These observations indicate that human APC can accelerate in vitro clot lysis by the inactivation of PAI-1 activity. However, the neutralization of PAI-1 by APC is independent of the presence or absence of protein S, phospholipid and Ca2+-ions.

THROMBOPHILIA:ITS CAUSES AND A ROUGH ESTIMATE OF ITS PREVALENCE

1987 ◽  
Author(s):  
E Briët ◽  
L Engesser ◽  
E J P Brommer ◽  
A W Broekmans ◽  
R M Bertina
Keyword(s):  
Plasminogen Activator ◽  
Protein C ◽  
Antithrombin Iii ◽  
Plasminogen Activator Inhibitor ◽  
Protein S ◽  
Factor Vii ◽  
Type I ◽  
Factor V ◽  
Protein C Deficiency ◽  
Familial Cases

Idiopathic venous thrombosis and embolism have gained widespread interest since the discovery that, deficiencies of antithrombin III, protein C, and protein S are associated with familial venous thrombophilia. The purpose of our study was to obtain an estimate of the prevalence of this syndrome and to establish the etiology in as many cases as possible.We collaborated with specialists from 37 Dutch hospitals, covering about 10% of the Dutch population. A history as well as blood samples were obtained from 113 unrelated cases with familial thrombophilia and from 90 isolated cases. Assuming that each proband in a family with thrombophilia has an average of four affected relatives, a rough estimate of the prevalence of familial thrombophilia in The Netherlands is 40 cases per 100.000. The prevalence of non-familial thrombophilia is probably lower.In 35 out of the 113 familial cases we established a diagnosis of hereditary antithrombin III deficiency (n=5), protein C deficiency (type I: n=9; type II: n=4), protein S deficiency (n=15) and dysfibrinogenemia (n=2). In 36 cases we found no abnormality at all and in the remaining 42 cases abnormalities were found in one or more of the following: heparin cofactor II, factor V, factor VII, factor VIII, von Willebrand factor, plasminogen, tissue plasminogen activator, plasminogen activator inhibitor, alpha 2 antiplasmin and histidine rich glycoprotein. In most of these cases, however, the hereditary nature of the abnormalities could not be demonstrated and the causal relationships remain to be established.In the 90 isolated cases, we diagnosed hereditary deficiencies of anti thrombin III, protein C and protein S each in one case and a lupus anticoagulant in two cases. In 54 cases no abnormality was found and in the remaining 31 cases various abnormalities were found in one or more of the proteins mentioned above.We conclude that the syndrome of thrombophilia is not rare but its true prevalence needs to be established by more rigorous means. An etiological diagnosis can be made with confidence in only one third of the familial cases and in less than 10 percent of the isolated cases.

scholarly journals Mechanism of protein C-dependent clot lysis: role of plasminogen activator inhibitor

Blood ◽  
1986 ◽  
Vol 68 (6) ◽  
pp. 1218-1223 ◽  
Author(s):  
Y Sakata ◽  
DJ Loskutoff ◽  
CL Gladson ◽  
CM Hekman ◽  
JH Griffin
Keyword(s):  
Plasminogen Activator ◽  
Protein C ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Activated Protein C ◽  
Plasminogen Activator Inhibitor ◽  
Species Specificity ◽  
Tissue Type ◽  
Clot Lysis ◽  
Activator Inhibitor

Abstract The mechanism by which activated protein C stimulates fibrinolysis was studied in a simple radiolabeled clot lysis assay system containing purified tissue-type plasminogen activator, bovine endothelial plasminogen activator inhibitor (PAI), plasminogen, 125I-fibrinogen and thrombin. Fibrinolysis was greatly enhanced by the addition of purified bovine activated protein C; however, in the absence of PAI, activated protein C did not stimulate clot lysis, thus implicating this inhibitor in the mechanism. In clot lysis assay systems containing washed human platelets as a source of PAI, bovine-activated protein C-dependent fibrinolysis was associated with a marked decrease in PAI activity as detected using reverse fibrin autography. Bovine-activated protein C also decreased PAI activity of whole blood and of serum. In contrast to the bovine molecule, human-activated protein C was much less profibrinolytic in these clot lysis assay systems and much less potent in causing the neutralization of PAI. This species specificity of activated protein C in clot lysis assays reflect the known in vivo profibrinolytic species specificity. When purified bovine-activated protein C was mixed with purified PAI, complex formation was demonstrated using immunoblotting techniques after polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. These observations suggest that a major mechanism for bovine protein C- dependent fibrinolysis in in vitro clot lysis assays involves a direct neutralization of PAI by activated protein C.

scholarly journals Continuous Active State of Coagulation System in Patients With Nonthrombotic Inflammatory Bowel Disease

2011 ◽  
Vol 17 (6) ◽  
pp. 600-604 ◽  
Author(s):  
Huseyin Alkim ◽  
Selime Ayaz ◽  
Canan Alkim ◽  
Aysel Ulker ◽  
Burhan Sahin
Keyword(s):  
Plasminogen Activator ◽  
Degradation Products ◽  
Plasminogen Activator Inhibitor ◽  
Protein S ◽  
Plasminogen Activator Inhibitor 1 ◽  
Inflammatory Bowel ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Activator Inhibitor ◽  
D Dimer

This study was planned for searching possible changes of the total coagulation and fibrinolysis system in inflammatory bowel disease (IBD) in order to obtain some clues for explaining the relation between IBD and hypercoagulability. A total of 24 patients with ulcerative colitis, 12 patients with Crohn disease, and 20 healthy controls were studied. Platelets; prothrombin time (PT); partial thromboplastin time (PTT); fibrinogen; d-dimer; fibrinogen degradation products; protein C; protein S; antithrombin; thrombin time; von Willebrand factor; coagulation factors V, VII, VIII, IX, XI, and XIII; plasminogen; antiplasmin; tissue plasminogen activator; plasminogen activator inhibitor 1; and prothrombin fragments 1 + 2 were studied. Most of the procoagulants (platelets, fibrinogen, von Willebrand factor, coagulation factor IX, and plasminogen activator inhibitor 1) were found increased together with decreases in some anticoagulants (protein S and antithrombin) in IBD. Also the activation markers of coagulation (d-dimer, fibrinogen degradation products, and prothrombin fragments 1 + 2) were all increased. The parameters of the total coagulation–fibrinolysis system were increased in IBD, regardless of the form and the activity of the disease.

scholarly journals A comparison between activated protein C and des-1-41-light chain- activated protein C in reactions with type 1 plasminogen activator inhibitor

Blood ◽  
1989 ◽  
Vol 74 (1) ◽  
pp. 173-181
Author(s):  
CL Gladson ◽  
RR Schleef ◽  
BR Binder ◽  
DJ Loskutoff ◽  
JH Griffin
Keyword(s):  
Plasminogen Activator ◽  
Light Chain ◽  
Protein C ◽  
Activated Protein C ◽  
Plasminogen Activator Inhibitor ◽  
Amidolytic Activity ◽  
Gla Domain ◽  
Activator Inhibitor ◽  
Pai 1

This study investigates the role of the gamma-carboxyglutamic acid (gla) containing domain of activated protein C in interactions with both platelet-derived and purified type 1 plasminogen activator inhibitor (PAI-1). The activity of human platelet PAI-1 was neutralized to the same extent by bovine activated protein C and bovine des-1–41- light chain-activated protein C. Both forms of activated protein C formed SDS-stable, divalent-cation independent complexes with platelet PAI-1, as demonstrated by immunoblotting using antibodies directed to either protein C or PAI-1. Since activated protein C neutralized PAI-1, the potential inhibition of the enzyme by PAI-1 was studied. Purified PAI-1 inhibited the amidolytic activity of bovine-activated protein C and bovine des-1–41-light chain-activated protein C with a k2 of 2.85 X 10(4) M-1 sec-1 for both proteins. These data suggest that the gla domain of activated protein C is not required for neutralization of PAI- 1 activity, for complex formation with PAI-1, or for inhibition of the amidolytic activity of activated protein C by PAI-1.

scholarly journals Inhibition of the intrinsic factor X activating complex by protein S: evidence for a specific binding of protein S to factor VIII

Blood ◽  
1995 ◽  
Vol 86 (3) ◽  
pp. 1062-1071 ◽  
Author(s):  
SJ Koppelman ◽  
TM Hackeng ◽  
JJ Sixma ◽  
BN Bouma
Keyword(s):  
Factor Viii ◽  
Protein C ◽  
Intrinsic Factor ◽  
Activated Protein C ◽  
Protein S ◽  
Inhibitory Effect ◽  
Factor X ◽  
Ic50 Values ◽  
Factor X Activation ◽  
Factor X Activating Complex

Protein S is a vitamin K-dependent nonenzymatic anticoagulant protein that acts as a cofactor to activated protein C. Recently it was shown that protein S inhibits the prothrombinase reaction independent of activated protein C. In this study, we show that protein S can also inhibit the intrinsic factor X activation via a specific interaction with factor VIII. In the presence of endothelial cells, the intrinsic activation of factor X was inhibited by protein S with an IC50 value of 0.28 +/- 0.04 mumol/L corresponding to the plasma concentration of protein S. This inhibitory effect was even more pronounced when the intrinsic factor X activation was studied in the presence of activated platelets (IC50 = 0.15 +/- 0.02 mumol/L). When a nonlimiting concentration of phospholipid vesicles was used, the plasma concentration of protein S (300 nmol/L) inhibited the intrinsic factor X activation by 40%. Thrombin-cleaved protein S inhibited the endothelial cell-mediated factor X activation with an IC50 similar to that of native protein S (0.26 +/- 0.02 mumol/L). Protein S in complex with C4b-binding protein inhibited the endothelial cell-mediated factor X activation more potently than protein S alone (IC50 = 0.19 +/- 0.03 mumol/L). Using thrombin activated factor VIII, IC50 values of 0.53 +/- 0.09 mumol/L and 0.46 +/- 0.10 mumol/L were found for native protein S and thrombin-cleaved protein S, respectively. The possible interactions of protein S with factor IXa, phospholipids, and factor VIII were investigated. The enzymatic activity of factor IXa was not affected by protein S, and interaction of protein S with the phospholipid surface could not fully explain the inhibitory effect of protein S on the factor X activation. Using a solid-phase binding assay, we showed a specific, saturable, and reversible binding of protein S to factor VIII with a high affinity. The concentration of protein S where half-maximal binding was reached (B1/2max) was 0.41 +/- 0.06 mumol/L. A similar affinity was found for the interaction of thrombin-cleaved protein S with factor VIII (B1/2max = 0.40 +/- 0.04 mumol/L). The affinity of the complex protein S with C4B-binding protein appeared to be five times higher (B1/2max = 0.07 +/- 0.03 mumol/L). Because the affinities of the interaction of the different forms of protein S with factor VIII correspond to the IC50 values observed for the intrinsic factor X activating complex, the interaction of protein S with factor VIII may explain the inhibitory effect of protein S on the intrinsic factor X activating complex.(ABSTRACT TRUNCATED AT 400 WORDS)

Sign in / Sign up

Export Citation Format

Share Document