scholarly journals Thrombin-Antithrombin III and Plasm in-Antiplasmin Complexes as Indicators of in Vivo Activation of the Coagulation and/or Fibrinolytic Systems

1977 ◽  
Author(s):  
D. Collen ◽  
F.de Cock
Keyword(s):  
Human Blood ◽  
Half Life ◽  
Antithrombin Iii ◽  
Enzyme Inhibitor ◽  
Degradation Products ◽  
Clinical Value ◽  
Fibrinogen Degradation Products ◽  
Prethrombotic State ◽  
Immunochemical Methods

Both the thrombin-antithrombin III and plasmin-antiplasmin complexes contain neoantigenic structures, not present in the parent molecules, to which non cross-reacting precipitating antibodies can be produced (Thromb.Res. 5, 577, 1974). This phenomenon has been used to develop immunochemical methods for the quantitation of these complexes in human blood (Thromb. Res 7, 235, 1975). Patients with in vivo activation of the coagulation and/or fibrinolytic systems consistently showed increased levels of enzyme-inhibitor complexes (Eur.J.Clin.Invest, in press, 1977). The circulatory half-life of these complexes was estimated to be several hours (0.5 to 0.75 days).On several occasions, increased plasmin-antiplasmin titers were observed in the presence of a normal screening hemostasis analysis, suggesting that these assays may be more sensitive indicators of in vivo activation of the coagulation-fibrinolytic systems that assays for fibrinogen degradation products.Studies to determine the clinical value of the measurement of these enzyme-inhibitor complexes as indicators of a prethrombotic state are in progress and will be reported.

Turnover of Human Extrinsic (Tissue-Type) Plasminogen Activator in Rabbits

1981 ◽  
Vol 46 (03) ◽  
pp. 658-661 ◽  
Author(s):  
C Korninger ◽  
J M Stassen ◽  
D Collen
Keyword(s):  
Plasminogen Activator ◽  
Intravenous Injection ◽  
Active Site ◽  
Half Life ◽  
Degradation Products ◽  
Gel Filtration ◽  
Tissue Type ◽  
Organ Distribution ◽  
Small Rise

SummaryThe turnover of highly purified human extrinsic plasminogen activator (EPA) (one- and two-chain form) was studied in rabbits. Following intravenous injection, EPA-activity declined rapidly. The disappearance rate of EPA from the plasma could adequately be described by a single exponential term with a t ½ of approximately 2 min for both the one-chain and two-chain forms of EPA.The clearance and organ distribution of EPA was studied by using 125I-labeled preparations. Following intravenous injection of 125I-1abeled EPA the radioactivity disappeared rapidly from the plasma also with a t ½ of approximately 2 min down to a level of 15 to 20 percent, followed by a small rise of blood radioactivity. Gel filtration of serial samples revealed that the secondary increase of the radioactivity was due to the reappearance of radioactive breakdown products in the blood. Measurement of the organ distribution of 125I at different time intervals revealed that EPA was rapidly accumulated in the liver, followed by a release of degradation products in the blood.Experimental hepatectomy markedly prolonged the half-life of EPA in the blood. Blocking the active site histidine of EPA had no effect on the half-life of EPA in blood nor on the gel filtration patterns of 125I in serial plasma samples.It is concluded that human EPA is rapidly removed from the blood of rabbits by clearance and degradation in the liver. Recognition by the liver does not require a functional active site in the enzyme. Neutralization in plasma by protease inhibitors does not represent a significant pathway of EPA inactivation in vivo.

The Leukocyte Digestion of Fibrinogen Degradation Products (FDP)

1971 ◽  
Vol 26 (03) ◽  
pp. 523-525
Author(s):  
K Gibiński ◽  
B Lipiński ◽  
M Trusz-Gluza
Keyword(s):  
Degradation Products ◽  
Fibrinogen Degradation Products

SummaryWhile the native fibrinogen is not digested by the leucocyte proteases both the early and late FDP are digestible without any denaturating reagent. Thus, this reaction may occur in vivo indicating an unknown role of granulocytes in paracoagulation.

scholarly journals In Vitro Characterization of Rabbit Thrombin, Antithrombin III, and Thrombin-Antithrombin III Complex, and Determination of Their Survival Times in Vivo

1977 ◽  
Author(s):  
Christine N. Vogel ◽  
Kingdon S. Henry ◽  
Roger L. Lundblad
Keyword(s):  
Gel Electrophoresis ◽  
Half Life ◽  
Antithrombin Iii ◽  
Specific Activity ◽  
Sodium Dodecyl ◽  
In Vivo Studies ◽  
Survival Times ◽  
At Iii

Our intention is to study the interaction of rabbit thrombin with antithrombin III (AT-III) in vitro and in vivo. After activation of crude prothrombin with tissue thromboplastin and CaCl2, thrombin was purified and showed two species of thrombin with molecular weights of 36,000 and 39,000 daltons as determined by sodium dodecyl sulfate discontinuous gel electrophoresis. Rabbit AT-III was purified using a heparin agarose column and had a molecular weight of 55,000 daltons. The inhibition of thrombin by AT-III was followed by fibrinogen clotting assays and an AT-III-thrombin complex was observed on gel electrophoresis. For the in vivo studies both thrombin and AT-III were radiolabelled with Na125i using the solid state lactoperoxidase method and retained 99% of the pre-iodinated specific activity. Radiolabelled thrombin and a radiolabelled AT-III-thrombin complex were injected into different rabbits. The rate of removal of both was very similar with a half-life of approximately 9 hours. When radiolabelled AT-III was injected, the half-life was approximately 60 hours. Since the disappearance rate of thrombin more closely approximates that of the preformed AT-III-thrombin complex and is clearly shorter than the turnover rate of AT-III, the possibility is raised that thrombin combines in vivo with a native inhibitor such as AT-III and may in fact be removed from the circulation as a complex rather than as a native molecule.

BIOLOGICAL PRETHROMBOTIC MARKERS AND COAGULATION INHIBITORS IN NEPHROTIC SYNDROME

1987 ◽  
Author(s):  
P Picard ◽  
J Y Borg ◽  
M Vasse ◽  
D Boudhabhay ◽  
J Soria ◽  
...  
Keyword(s):  
Nephrotic Syndrome ◽  
Acute Phase Proteins ◽  
Degradation Products ◽  
Protein S ◽  
Factor Vii ◽  
Activated Factor Vii ◽  
Prethrombotic State ◽  
At Iii ◽  
Coagulation Inhibitors

Nephrotic syndrome (NS) has long been recognized as a clinical prethrombotic state, because of severe thrombo-embolic complications. But underlying mechanisms are still poorly defined. In 56 untreated nephrotic adult patients (most of them without renal failure), we investigate in vivo coagulation activation by measuring 0 plasmatic specific fibrin degradation products (FbDP) (immuno-enzymological assay using a monoclonal anti D-neo antibody) and (2) the ratio of factor VII coagulant activity (V11c) to factor VII:Anti gen (VII;Ag) tested by an ELISA method. We examined coagulation inhibitors in plasmas and urines (antithrombin III—AT III, heparin cofactor II-HC II by amidolytic and laurell methods; protein C-PC by an ELISA assay ;free and bound protein S—PS:Ag by laurell assays). In few patients we also determinecjfribronectin and t-PA inhibitor.Results in plasma are submitted and expressed as mean ± DS and compared (t test) with controls (C) without nephropathySignificantly elevated activated factor VII and FbDP levels show an “in vivo activation” of coagulation in NS. Plasmatic fibronectin, HC II, PC:frg, and tPA-I levels are alsp significantly elevated and roughly paralleled fibrinogen (6,25 ± 2,9 g/1) and other acute-phase proteins measurements. Significant amounts of AT 111:Ag were present in about half tested urines, but in a degraded form with low or absent heparin cofactor activity. Mean plasmatic AT III concentration was in normal range, but three of the 4 patients with a thrombotic disease had the lowest values of AT III and the highest fibrinogen levels.We could demonstrate a biological prethrombotic state in NS and suggest the way of identifying patients with high risk of thrombosis.

scholarly journals A fluorescent residualizing label for studies on protein uptake and catabolism in vivo and in vitro

1990 ◽  
Vol 267 (1) ◽  
pp. 155-162 ◽  
Author(s):  
J L Maxwell ◽  
L Terracio ◽  
T K Borg ◽  
J W Baynes ◽  
S R Thorpe
Keyword(s):  
Half Life ◽  
Normal Tissue ◽  
Degradation Products ◽  
Rat Serum ◽  
Peripheral Tissues ◽  
Protein Uptake ◽  
Kinetics Of ◽  
Rat Serum Albumin

Residualizing labels are tracers which remain in lysosomes after uptake and catabolism of the carrier protein and have been especially useful for studies on the sites of plasma protein degradation. Thus far these labels have contained radioactive reporters such as 3H or 125I. In the present paper we describe a fluorescent residualizing label, NN-dilactitol-N′-fluoresceinylethylenediamine (DLF). Modification of asialofetuin (ASF) or rat serum albumin (RSA) with DLF affected neither their normal kinetics of clearance from the rat circulation nor their normal tissue sites of uptake and degradation. After injection of DLF-ASF, fluorescent degradation products were recovered nearly quantitatively in liver and retained with a half-life of about 2 days. Fluorescent degradation products from DLF-RSA were recovered in skin and muscle, and were localized in fibroblasts by fluorescence microscopy. These results confirm previous studies with radioactive residualizing labels in which fibroblasts in peripheral tissues were identified as primary sites of albumin degradation. Fluorescent catabolites also accumulated in fibroblasts incubated with DLF-RSA in vitro, and residualized with a half-life of about 2 days. Overall, the data establish that DLF functions efficiently as a fluorescent residualizing label both in vivo and in vitro. The advantages of fluorescent, compared with radioactive, residualizing labels should make them valuable tools for studies on protein uptake and catabolism in biological systems.

scholarly journals Engineering of Long-Circulating Peptidoglycan Hydrolases Enables Efficient Treatment of Systemic Staphylococcus aureus Infection

mBio ◽  
2020 ◽  
Vol 11 (5) ◽  
Author(s):  
Anna M. Sobieraj ◽  
Markus Huemer ◽  
Léa V. Zinsli ◽  
Susanne Meile ◽  
Anja P. Keller ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Human Blood ◽  
Half Life ◽  
Multidrug Resistant ◽  
Life Extension ◽  
Drug Resistant ◽  
Content Type ◽  
Peptidoglycan Hydrolases ◽  
Life Threatening

ABSTRACT Staphylococcus aureus is a human pathogen causing life-threatening diseases. The increasing prevalence of multidrug-resistant S. aureus infections is a global health concern, requiring development of novel therapeutic options. Peptidoglycan-degrading enzymes (peptidoglycan hydrolases, PGHs) have emerged as a highly effective class of antimicrobial proteins against S. aureus and other pathogens. When applied to Gram-positive bacteria, PGHs hydrolyze bonds within the peptidoglycan layer, leading to rapid bacterial death by lysis. This activity is highly specific and independent of the metabolic activity of the cell or its antibiotic resistance patterns. However, systemic application of PGHs is limited by their often low activity in vivo and by an insufficient serum circulation half-life. To address this problem, we aimed to extend the half-life of PGHs selected for high activity against S. aureus in human serum. Half-life extension and increased serum circulation were achieved through fusion of PGHs to an albumin-binding domain (ABD), resulting in high-affinity recruitment of human serum albumin and formation of large protein complexes. Importantly, the ABD-fused PGHs maintained high killing activity against multiple drug-resistant S. aureus strains, as determined by ex vivo testing in human blood. The top candidate, termed ABD_M23, was tested in vivo to treat S. aureus-induced murine bacteremia. Our findings demonstrate a significantly higher efficacy of ABD_M23 than of the parental M23 enzyme. We conclude that fusion with ABD represents a powerful approach for half-life extension of PGHs, expanding the therapeutic potential of these enzybiotics for treatment of multidrug-resistant bacterial infections. IMPORTANCE Life-threatening infections with Staphylococcus aureus are often difficult to treat due to the increasing prevalence of antibiotic-resistant bacteria and their ability to persist in protected niches in the body. Bacteriolytic enzymes are promising new antimicrobials because they rapidly kill bacteria, including drug-resistant and persisting cells, by destroying their cell wall. However, when injected into the bloodstream, these enzymes are not retained long enough to clear an infection. Here, we describe a modification to increase blood circulation time of the enzymes and enhance treatment efficacy against S. aureus-induced bloodstream infections. This was achieved by preselecting enzyme candidates for high activity in human blood and coupling them to serum albumin, thereby preventing their elimination by kidney filtration and blood vessel cells.

Molar Concentrations of Fibrinolytic Components, Especially Free Fibrinolysin, in Vivo

1975 ◽  
Vol 33 (02) ◽  
pp. 244-255
Author(s):  
L. B Nanninga
Keyword(s):  
Dissociation Constant ◽  
Trypsin Inhibitor ◽  
Human Blood ◽  
Half Life ◽  
Average Concentration ◽  
Soybean Trypsin Inhibitor ◽  
Complete Conversion ◽  
Normal Human ◽  
Normal Human Blood

SummaryThe levels of fibrinogen and of Profibrinolysin (plasminogen) in urokinase-treated plasma as a function of time of incubation were measured. The Profibrinolysin concentration was estimated through its complete conversion to fibrinolysin and the inhibition of the enzyme by crystalline soybean trypsin inhibitor. The dissociation constant of the FL-STX complex was determined to be 7 × 10–9 M. The average concentration of Profibrinolysin in normal human citrated plasma was found to be 8 × 10–7 M. From the decrease of fibrinogen with time in the urokinase-treated plasma, the free fibrinolysin was calculated. Free fibrinolysin in normal human blood in vivo was estimated from the half-life of fibrinogen and other data obtained in this study to be present at a concentration of 1.7 × 10–10 M. The plasmakinase activity in vivo, expressed as urokinase molarity, is also about 2 × 10–10 M.

Unreliability of Current Serum Fibrin Degradation Product (FDP) Assays

1985 ◽  
Vol 53 (03) ◽  
pp. 301-302 ◽  
Author(s):  
P J Gaffney ◽  
M J Perry
Keyword(s):  
Monoclonal Antibodies ◽  
Serum Level ◽  
Degradation Product ◽  
Degradation Products ◽  
Polyclonal Antibodies ◽  
Fibrin Degradation Product ◽  
Serum Samples ◽  
Fibrinogen Degradation Products ◽  
A Value

SummaryPreviously, assays of fibrin-fibrinogen degradation products (FDP) had to be performed on serum samples. However, monoclonal antibodies (Mabs) are now available which permit the measurement of FDP directly in plasma. We have employed two Mabs, one monospecific for FDP originating from crosslinked fibrin and another panspecific for the FDP fraction, to determine normal FDP levels in plasma and serum. The monospecific Mab gave a value of 40 ng FDP/ml in plasma and 10 ng/ml in serum, while the serum level of FDP recorded using the panspecific Mab was >1000 ng/ml, at all the concentrations of thrombin employed. Similarly, when a solution of purified fibrinogen was treated with thrombin, the concentration of FDP present in the clot supernatant was >1000 ng/ml when assayed using the panspecific Mab. Thus during serum preparation as much as 75% of the native FDP is incorporated into the clot while in excess of 1000 ng/ml of laboratory generated FDP, probably incompletely polymerized fibrin, is measured using panspecific antisera. These data indicate that current FDP assays using polyclonal antibodies are not a reliable reflection of the FDP level generated in vivo. The use of FDP-specific Mabs which do not react with fibrinogen is recommended for future FDP assays performed directly on plasma.

scholarly journals Effect of Angiography on Blood Coagulation

1977 ◽  
Author(s):  
W. H. Krause ◽  
A. Lang
Keyword(s):  
Contrast Media ◽  
Prothrombin Time ◽  
Antithrombin Iii ◽  
Degradation Products ◽  
Anticoagulant Activity ◽  
Thromboembolic Complication ◽  
Thrombin Time ◽  
Media Concentration

It is known, that angiographic contrast media have an anticoagulant activity in vitro. The purpose of the present study was, to investigate this effect in vivo. The catheter was introduced percutaneously according to Seldinger into the femoral artery. The prothrombin time, activated thromboplastin time (APTT), thrombin time, reptilase time, fibrinogen, plasminogen, antithrombin III, platelets, fibrin/fibrinogen degradation products (FDP), haematocrit and contrast media concentration were studied in a series of 50 patients before and following abdominal aorto-arteriographic procedures up to 6 hours. Thrombin time and reptilase time were prolonged significantly 30 and 60 minutes after angiography. There was a correlation between clotting tiies and contrast media concentrations. Prothrombin time, APTT, and platelet counts remained unchanged. Fibrinogen, plasminogen,and antithrombin III levels showed a significant reduction after 30 minutes. FDP concentrations were increased significantly up to 6 hours, there was no correlation between contrast media concentrations and split products. The results were corrected for contrast media dilution according to the haematocrit. No thromboembolic complication was observed. The results suggest that angiographic procedure may initiate an intravascular coagulation with an activation of the fibrinolytic system. In addition the contrast media showed an inhibition of fibrin polymerization in vivo.

Evaluation of the safety, recovery, half-life, and clinical efficacy of antithrombin III (human) in patients with hereditary antithrombin III deficiency. Cooperative Study Group [see comments]

Blood ◽  
1990 ◽  
Vol 75 (1) ◽  
pp. 33-39 ◽  
Author(s):  
D Menache ◽  
JP O'Malley ◽  
JB Schorr ◽  
B Wagner ◽  
C Williams ◽  
...  
Keyword(s):  
Half Life ◽  
Antithrombin Iii ◽  
Clinical Symptoms ◽  
Cooperative Study Group ◽  
Significant Difference ◽  
At Iii ◽  
Thrombotic Complications ◽  
Antithrombin Iii Deficiency

Antithrombin III (Human) (AT III) was administered to 18 patients with documented hereditary AT III deficiency. In eight patients with no ongoing clinical symptoms of thrombosis, the percent increase per unit AT III infused per kilogram of body weight ranged from 1.56% to 2.74%, and the half-life from 43.3 to 77.0 hours. No significant difference was noted between patients receiving and those not receiving coumarin therapy. In clinically ill patients, the in vivo recovery was significantly lower and ranged from 0.64% to 1.90% increase per unit AT III infused/kg. Efficacy of AT III was evaluated in 13 patients for the prevention or treatment of thrombosis. AT III was efficacious as assessed by the absence of thrombotic complications after surgery and/or parturition, and the nonextension and nonrecurrence of thrombosis in patients exhibiting an acute thrombotic episode. No side effects were noted. Follow-up studies indicated no hepatitis B seroconversion and no alanine aminotransferase elevations in patients who were not transfused with other blood products.

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