Studies on the Enzymatic Activity of the Antihemophilic Factor (Factor VIII)

1967 ◽  
Vol 17 (01/02) ◽  
pp. 188-193 ◽  
Author(s):  
S van Creveld ◽  
I. A Mochtar ◽  
C. N Pascha
Keyword(s):  
Enzymatic Activity ◽  
Factor Viii ◽  
Esterase Activity ◽  
Barium Sulphate ◽  
Screening Tests ◽  
Normal Human ◽  
The Stability ◽  
Fraction I ◽  
Antihemophilic Factor ◽  
Esterase Activities

SummaryPreparations of normal human antihemophilic factor (AHF, factor VIII) obtained by continuous free electrophoresis in the “Elphor” apparatus, were investigated for enzymatic activity on various substrates. A number of enzymatic activities could be excluded by screening tests, performed with fraction I of Cohn. In some preparations esterase-activity was demonstrable on the substrates benzoyl-arginyl-ethylester (BAEE) and on glycerol tributyrate. There was, however, no correlation between these esterase-activities and the AHF-activity in the preparations. Moreover, the stability of the esterase at 4° C was much greater than the stability of the AHF-activity. We therefore assume that the AHF has no enzymatic activity on these substrates under the conditions of the tests. Attempts to activate AHF by calcium, magnesium or serum, were unsuccessful. Both esterase-activities were also present in fraction I of Cohn prepared from normal human citrated or resin plasma. The esterase-activity on BAEE is removed from resin plasma by adsorption to barium sulphate. The esterase-activity on glycerol tributyrate is not adsorbed.

scholarly journals The factor VIII complex: structure and function

Blood ◽  
1981 ◽  
Vol 58 (1) ◽  
pp. 1-13 ◽  
Author(s):  
LW Hoyer
Keyword(s):  
Factor Viii ◽  
Complex Structure ◽  
Related Protein ◽  
Molecular Defects ◽  
Normal Human ◽  
And Function ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Antihemophilic Factor ◽  
Immunologic Properties

Abstract Normal human plasma contains a complex of two proteins that are important in hemostasis and coagulation. The factor VIII procoagulant protein (antihemophilic factor) and the factor VIII-related protein (von Willebrand factor) are under separate genetic control, have distinct biochemical and immunologic properties, and have unique and essential physiologic functions. While the nature of their interaction and the details of the biochemical structures remain to be determined, the information now available permits a preliminary understanding of the molecular defects in hemophilia and von Willebrand's diseases.

scholarly journals Immunologic Studies of Antihemophilic Factor (AHF, Factor VIII) II. Properties of Cross-reacting Material

Blood ◽  
1970 ◽  
Vol 35 (6) ◽  
pp. 809-820 ◽  
Author(s):  
LEON W. HOYER ◽  
ROBERT T. BRECKENRIDGE
Keyword(s):  
Calcium Phosphate ◽  
Physical Properties ◽  
Factor Viii ◽  
Barium Sulfate ◽  
Genetic Variant ◽  
Hemophilia A ◽  
Procoagulant Activity ◽  
Normal Plasma ◽  
Fraction I ◽  
Antihemophilic Factor

Abstract Patients with a genetic variant of hemophilia A have in their plasmas material which has antigenic characteristics similar to those of antihemophilic factor (AHF). The physical properties of the biologically inactive cross-reacting material (CRM) are like those of AHF from normal plasma. The CRM is concentrated in Cohn fraction I and in cryoprecipitates and is not adsorbed from plasma by calcium phosphate or barium sulfate. It is inactivated by heating to 56° for 30 minutes. The CRM is less sensitive to thrombin inactivation than AHF and is recovered in serum. The similar properties of AHF and CRM support the hypothesis that patients with this genetic variant of hemophilia A synthesize a material similar to AHF but lacking procoagulant activity.

scholarly journals The factor VIII complex: structure and function

Blood ◽  
1981 ◽  
Vol 58 (1) ◽  
pp. 1-13 ◽  
Author(s):  
LW Hoyer
Keyword(s):  
Factor Viii ◽  
Complex Structure ◽  
Related Protein ◽  
Molecular Defects ◽  
Normal Human ◽  
And Function ◽  
Von Willebrand ◽  
Willebrand Factor ◽  
Antihemophilic Factor ◽  
Immunologic Properties

Normal human plasma contains a complex of two proteins that are important in hemostasis and coagulation. The factor VIII procoagulant protein (antihemophilic factor) and the factor VIII-related protein (von Willebrand factor) are under separate genetic control, have distinct biochemical and immunologic properties, and have unique and essential physiologic functions. While the nature of their interaction and the details of the biochemical structures remain to be determined, the information now available permits a preliminary understanding of the molecular defects in hemophilia and von Willebrand's diseases.

The Separation of AHF from Fibrinogen. IV

1966 ◽  
Vol 15 (03/04) ◽  
pp. 338-342
Author(s):  
S van Creveld ◽  
I. A Mochtar ◽  
C. N Pascha
Keyword(s):  
Factor Viii ◽  
Continuous Flow ◽  
Caproic Acid ◽  
Starting Material ◽  
Free Products ◽  
Molar Solution ◽  
Normal Human ◽  
Continous Flow ◽  
Fraction I

SummaryThe anti-hemophilic factor (AHF, factor VIII) has been separated from fibrinogen by means of continous flow electrophoresis. The starting material was Cohn’s fraction I, prepared from normal human resinplasma. These fibrinogen-free products still contained proteins without AHF-activity. Part of these contaminating proteins could be extracted from fraction I by means of a 1 molar solution of epsilon amino caproic acid. The residue, principally consisting of fibrinogen and AHF, was dissolved in a triethylamine buffer and subjected to continuous flow electrophoresis. The resulting AHF-preparations were free from fibrinogen. By immuno-electrophoresis no proteins without AHF-activity could be demonstrated in these preparations.

Antihemophilic Factor: Its Presence in Fibrinogen, Assay Problems and the Stability of Lyophilized AHF-Fibrinogen Preparations

1963 ◽  
Vol 09 (02) ◽  
pp. 354-367 ◽  
Author(s):  
Werner Baumgarten ◽  
Benjamin E. Sanders ◽  
Benita D Belkin ◽  
Frank E Pagenkemper ◽  
William G Albers ◽  
...  
Keyword(s):  
Human Plasma ◽  
Control Procedure ◽  
Factor Activity ◽  
Normal Human Plasma ◽  
Human Fibrinogen ◽  
Normal Human ◽  
Average Activity ◽  
The Stability ◽  
Antihemophilic Factor ◽  
Generation Test

SummaryThe thromboplastin generation test of Biggs et al. and of Pitney, and adopted by Surgenor for the assay of antihemophilic factor activity in lyophilized preparations of human fibrinogen, has been modified to yield a selfcontained statistically valid assay. This procedure was designed to serve primarily as a control procedure. The AHF activity of production lots of human fibrinogen was assayed, and the stability of AHF under different conditions of storage was determined.The procedure described in this paper is a satisfactory control procedure for AHF potency testing. In the absence of a generally recognized unit of AHF potency, it would seem most helpful to the clinician to have the potency related to the average activity in fresh normal human plasma.

Purification of the Antihemophilic Factor by Gel Filtration on Agarose

1969 ◽  
Vol 22 (03) ◽  
pp. 577-583 ◽  
Author(s):  
M.M.P Paulssen ◽  
A.C.M.G.B Wouterlood ◽  
H.L.M.A Scheffers
Keyword(s):  
Factor Viii ◽  
Plasma Proteins ◽  
Large Scale ◽  
Gel Filtration ◽  
Large Scale Preparation ◽  
Scale Preparation ◽  
Antihemophilic Factor

SummaryFactor VIII can be isolated from plasma proteins, including fibrinogen by chromatography on agarose. The best results were obtained with Sepharose 6B. Large scale preparation is also possible when cryoprecipitate is separated by chromatography. In most fractions containing factor VIII a turbidity is observed which may be due to the presence of chylomicrons.The purified factor VIII was active in vivo as well as in vitro.

Purification of Antihemophilic Factor (Factor VIII) by Amino Acid Precipitation*

1964 ◽  
Vol 11 (01) ◽  
pp. 064-074 ◽  
Author(s):  
Robert H Wagner ◽  
William D McLester ◽  
Marion Smith ◽  
K. M Brinkhous
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Factor Viii ◽  
Plasma Protein ◽  
Acid Precipitation ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Specific Procedure ◽  
Beta Alanine ◽  
Antihemophilic Factor

Summary1. The use of several amino acids, glycine, alpha-aminobutyric acid, alanine, beta-alanine, and gamma-aminobutyric acid, as plasma protein precipitants is described.2. A specific procedure is detailed for the preparation of canine antihemophilic factor (AHF, Factor VIII) in which glycine, beta-alanine, and gammaaminobutyric acid serve as the protein precipitants.3. Preliminary results are reported for the precipitation of bovine and human AHF with amino acids.

Investigations on the Nature of Hemophilia A

1963 ◽  
Vol 09 (01) ◽  
pp. 030-052 ◽  
Author(s):  
Eberhard Mammen
Keyword(s):  
Factor Viii ◽  
Human Plasma ◽  
Barium Sulfate ◽  
Freeze Drying ◽  
Room Temperature ◽  
Hemophilia A ◽  
Normal Human Plasma ◽  
Normal Human ◽  
And Storage ◽  
Prothrombin Activation

SummaryIn this paper an inhibitor is described that is found in hemophilic plasma and serum different from any till now described inhibitor. The inhibitor only inhibits prothrombin activation in the “intrinsic clotting systems”. This inhibitor is probably not present in normal human plasma or serum. It is destroyed by ether and freeze drying, is labile to acid and storage at room temperature. It is stable upon dialysis and has not been adsorbed on barium sulfate, aluminum hydroxide or kaolin. It precipitates at 50% v/v saturation with alcohol. The nature of this inhibitor seems to be a protein or lipoprotein.Factor VIII was isolated from hemophilic plasma. The amount isolated was the same as from normal plasma and the activity properties were not different. Hemophiliacs have normal amounts of factor VIII.

Use of Factor VIII in the Treatment of Hemophilia

1962 ◽  
Vol 07 (02) ◽  
pp. 230-238 ◽  
Author(s):  
A Pavlovsky ◽  
H Peterson ◽  
G Casillas ◽  
C Simonetti ◽  
A Martinez Canaveri ◽  
...  
Keyword(s):  
Factor Viii ◽  
Tannic Acid ◽  
Deae Cellulose ◽  
Fibrinolytic System ◽  
Purification Method ◽  
Fraction I

SummaryThis publication describes the results obtained by treatment of haemophiliacs with factor VIII preparations isolated from Cohn fraction I by use of tannic acid, FI-O-Ta.The authors stress the rapidity of the disappearance of factor VIII after injection. Transfusions are generally well tolerated. One reaction of the pyrogen type has been observed and also a case of activation of the fibrinolytic system.A second purification method by means of chromatography on DEAE-cellulose is described.

Laboratory Detection of Female Carriers of Canine Hemophilia

1964 ◽  
Vol 12 (02) ◽  
pp. 368-376 ◽  
Author(s):  
B. J Parks ◽  
K. M Brinkhous ◽  
P. F Harris ◽  
G. D Penick
Keyword(s):  
Factor Viii ◽  
Partial Thromboplastin Time ◽  
Screening Test ◽  
Factor Viii Level ◽  
Viii Level ◽  
Antihemophilic Factor ◽  
Female Carriers

SummaryFemales known to be heterozygous for canine hemophilia had a plasma antihemophilic factor (AHF, factor VIII) level of about 50%, as determined by bioassay and by the effectiveness of their transfused plasma in raising the AHF levels of hemophilic dogs. Determination of the plasma AHF should serve to identify transmitter females prior to appearance of affected progeny in litters. Lyon’s hypothesis appears to apply to our findings.The simple partial thromboplastin time (PTT) test was prolonged in heterozygous females. Modifications of the test, by the addition of thrombin, a serum accelerator preparation, or kaolin, gave consistently longer PTT values for heterozygotes than for normal dogs. The PTT appears useful as a screening test for carriers of canine hemophilia.

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