DEVELOPMENT OF A PROTEIN C CONCENTRATE

1987 ◽  
Author(s):  
Prabir Bhattacharya ◽  
Carolyn L Orthner ◽  
Dudley K Strickland
Keyword(s):  
Protein C ◽  
Antithrombin Iii ◽  
Activated Protein C ◽  
Protein S ◽  
Exchange Chromatography ◽  
Factor Ix ◽  
Human Protein ◽  
Red Cross ◽  
American Red Cross ◽  
Protein C Concentrate

A Protein C (PC) concentrate may be useful in treating patients with congenital or acquired Protein C deficiencies. A method for preparation of a human Protein C concentrate has been developed using a by-product of American Red Cross Factor IX production as the starting material (Menache et. al. Blood, 64, 1220). Levels of other vitamin K dependent proteins in the Protein C concentrate were measured and found to be <10 units per 100 units of PC, except for Protein S. The level of Protein S as judged by immunological assay was 30 u/100 u PC. Assay of the PC concentrate using chrcmogenic substrates revealed that levels of thrombin, Factor 3�a and Factor IXa were less than 0.006 u/mL. In addition, Antithrombin III and ax -macroglobulin were not detected. The vivo effects of Protein C concentrate and Protein C activated by thrombin have been tested in anesthetized rabbits. Thrombin was removed from the activated Protein C by ion-exchange chromatography; depletion was verified by S-2238 or by a clotting assay (< 0.006 u/mL). Rabbits were injected with Protein C concentrate (400 ug/kg) or activated Protein C 24 - 48 ug/Kg). The activated partial thromboplastin time (APTT), FactorV (FV) and Factor VIII (FVIII) levels were measured in samples collected over the next three hours. Infusion of PC concentrate elevated the level of PC to 150% of the preinfusion level within 30 min. It did not change the levels of FV, FVIII, fibrinogen or platelet count. In contrast, infusion of activated Protein C produced progressive prolongation of the APTT. Levels of FV and FVIII were decreased to 25% and 50% of preinfusion levels, respectivelv, three hours after the infusion. Fibrinogen and platelet levels were unchanged during that period. These data demonstrate that activated human Protein C concentrate induces an anticoagulant effect that can be readily measured in rabbits.

scholarly journals Role of individual gamma-carboxyglutamic acid residues of activated human protein C in defining its in vitro anticoagulant activity

Blood ◽  
1992 ◽  
Vol 80 (4) ◽  
pp. 942-952 ◽  
Author(s):  
L Zhang ◽  
A Jhingan ◽  
FJ Castellino
Keyword(s):  
Protein C ◽  
Anticoagulant Activity ◽  
Coagulation Factor ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Factor Ix ◽  
Human Protein ◽  
Complete Disappearance ◽  
Carboxyglutamic Acid

Abstract To evaluate the contributions of individual gamma-carboxyglutamic acid (gla) residues to the overall Ca(2+)-dependent anticoagulant activity of activated human protein C (APC), we used recombinant (r) DNA technology to generate protein C (PC) variants in which each of the gla precursor glutamic acid (E) residues (positions 6, 7, 14, 16, 19, 20, 25, 26, and 29) was separately altered to aspartic acid (D). In one case, a gla26V mutation ([gla26V]r-PC) was constructed because a patient with this particular substitution in coagulation factor IX had been previously identified. Two additional r-PC mutants were generated, viz, an r-PC variant containing a substitution at arginine (R) 15 ([R15]r-PC), because this particular R residue is conserved in all gla- containing blood coagulation proteins, as well as a variant r-PC with substitution of an E at position 32 ([F31L, Q32E]r-PC), because gla residues are found in other proteins at this sequence location. This latter protein did undergo gamma-carboxylation at the newly inserted E32 position. For each of the 11 recombinant variants, a subpopulation of PC molecules that were gamma-carboxylated at all nonmutated gla- precursor E residues has been purified by anion exchange chromatography and, where necessary, affinity chromatography on an antihuman PC column. The r-PC muteins were converted to their respective r-APC forms and assayed for their amidolytic activities and Ca(2+)-dependent anticoagulant properties. While no significant differences were found between wild-type (wt) r-APC and r-APC mutants in the amidolytic assays, lack of a single gla residue at any of the following locations, viz, 7, 16, 20, or 26, led to virtual complete disappearance of the Ca(2+)-dependent anticoagulant activity of the relevant r-APC mutant, as compared with its wt counterpart. On the other hand, single eliminations of any of the gla residues located at positions 6, 14, or 19 of r-APC resulted in variant recombinant molecules with substantial anticoagulant activity (80% to 92%), relative to wtr-APC. Mutation of gla residues at positions 25 and 29 resulted in r-APC variants with significant but low (24% and 9% of wtr-APC, respectively) levels of anticoagulant activity. The variant, [R15L]r-APC, possessed only 19% of the anticoagulant activity of wrt-APC, while inclusion of gla at position 32 in the variant, [F31L, Q32gla]r-APC, resulted in a recombinant enzyme with an anticoagulant activity equivalent to that of wtr-APC.

scholarly journals Role of individual gamma-carboxyglutamic acid residues of activated human protein C in defining its in vitro anticoagulant activity

Blood ◽  
1992 ◽  
Vol 80 (4) ◽  
pp. 942-952
Author(s):  
L Zhang ◽  
A Jhingan ◽  
FJ Castellino
Keyword(s):  
Protein C ◽  
Anticoagulant Activity ◽  
Coagulation Factor ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Factor Ix ◽  
Human Protein ◽  
Complete Disappearance ◽  
Carboxyglutamic Acid

To evaluate the contributions of individual gamma-carboxyglutamic acid (gla) residues to the overall Ca(2+)-dependent anticoagulant activity of activated human protein C (APC), we used recombinant (r) DNA technology to generate protein C (PC) variants in which each of the gla precursor glutamic acid (E) residues (positions 6, 7, 14, 16, 19, 20, 25, 26, and 29) was separately altered to aspartic acid (D). In one case, a gla26V mutation ([gla26V]r-PC) was constructed because a patient with this particular substitution in coagulation factor IX had been previously identified. Two additional r-PC mutants were generated, viz, an r-PC variant containing a substitution at arginine (R) 15 ([R15]r-PC), because this particular R residue is conserved in all gla- containing blood coagulation proteins, as well as a variant r-PC with substitution of an E at position 32 ([F31L, Q32E]r-PC), because gla residues are found in other proteins at this sequence location. This latter protein did undergo gamma-carboxylation at the newly inserted E32 position. For each of the 11 recombinant variants, a subpopulation of PC molecules that were gamma-carboxylated at all nonmutated gla- precursor E residues has been purified by anion exchange chromatography and, where necessary, affinity chromatography on an antihuman PC column. The r-PC muteins were converted to their respective r-APC forms and assayed for their amidolytic activities and Ca(2+)-dependent anticoagulant properties. While no significant differences were found between wild-type (wt) r-APC and r-APC mutants in the amidolytic assays, lack of a single gla residue at any of the following locations, viz, 7, 16, 20, or 26, led to virtual complete disappearance of the Ca(2+)-dependent anticoagulant activity of the relevant r-APC mutant, as compared with its wt counterpart. On the other hand, single eliminations of any of the gla residues located at positions 6, 14, or 19 of r-APC resulted in variant recombinant molecules with substantial anticoagulant activity (80% to 92%), relative to wtr-APC. Mutation of gla residues at positions 25 and 29 resulted in r-APC variants with significant but low (24% and 9% of wtr-APC, respectively) levels of anticoagulant activity. The variant, [R15L]r-APC, possessed only 19% of the anticoagulant activity of wrt-APC, while inclusion of gla at position 32 in the variant, [F31L, Q32gla]r-APC, resulted in a recombinant enzyme with an anticoagulant activity equivalent to that of wtr-APC.

Patients with APC Resistance Compared with Those with Other Clotting Inhibitor Deficiencies Show Later Onset of Venous Thrombosis During Oral Contraception

1995 ◽  
Vol 1 (4) ◽  
pp. 274-276 ◽  
Author(s):  
Antonio Girolami ◽  
Paolo Simioni ◽  
Sandra Zanardi ◽  
Luigi Scarano ◽  
Bruno Girolami
Keyword(s):  
Deep Vein Thrombosis ◽  
Protein C ◽  
Antithrombin Iii ◽  
Activated Protein C ◽  
Protein S ◽  
Oral Contraception ◽  
Vein Thrombosis ◽  
Apc Resistance ◽  
At Iii ◽  
Deep Vein

The prevalence of deep vein thrombosis in female patients with antithrombin III (AT III), protein C, or protein S deficiency who are on oral contraception has been compared with that of patients with activated protein C (APC) resistance. In the latter case the prevalence was lower (36.4%) than in the AT III deficiency group (71.4%) but similar to that seen in the protein C and protein S group (25%).' Furthermore, venous thrombosis occurred with APC resistance much later than with AT III, protein C, or protein S defects. The time lag between onset of oral contraception and thrombosis (~16 cycles) was not statistically different from that seen in a group of women who were known to have no antithrombin III, protein C, or protein S defects. It appears that as far as the interaction with oral contraception is concerned APC resistance is a much less severe condition compared with other clotting inhibitor defects. Key Words: Oral contraceptive—Activated protein C resistance—Deep vein thrombosis.

Resistance to activated protein C, the FV: Q506 allele, and venous thrombosis

1998 ◽  
Vol 18 (01) ◽  
pp. 1-10
Author(s):  
A. Hillarp ◽  
S. Rosen ◽  
B. Zöller ◽  
B. Dahlbäck
Keyword(s):  
Venous Thrombosis ◽  
Protein C ◽  
Antithrombin Iii ◽  
Single Point ◽  
Activated Protein C ◽  
Factor Xa ◽  
Protein S ◽  
Single Point Mutation ◽  
Factor V ◽  
Endothelial Cell Surface

SummaryVitamin K-dependent protein C is an important regulator of blood coagulation. After its activation on the endothelial cell surface by thrombin bound to thrombomodulin, it cleaves and inactivates procoagulant cofactors Va and Villa, protein S and intact factor V working as cofactors. Until recently, genetic defects of protein C or protein S were, together with antithrombin III deficiency, the established major causes of familial venous thromboembolism, but they were found in fewer than 5-10% of patients with thrombosis. In 1993, inherited resistance to activated protein C (APC) was described as a major risk factor for venous thrombosis. It is found in up to 60% of patients with venous thrombosis. In more than 90% of cases, the molecular background for the APC resistance is a single point mutation in the factor V gene, which predicts substitution of an arginine (R) at position 506 by a glutamine (Q). Mutated factor V (FV: Q506) is activated by thrombin or factor Xa in normal way, but impaired inactivation of mutated factor Va by APC results in life-long hypercoagulability. The prevalence of the FV:Q506 allele in the general population of Western countries varies between 2 and 15%, whereas it is not found in several other populations with different ethnic backgrounds. Owing to the high prevalence of FV:Q506 in Western populations, it occasionally occurs in patients with deficiency of protein S, protein C, or antithrombin III. Individuals with combined defects suffer more severely from thrombosis, and often at a younger age, than those with single defects, suggesting severe thrombophilia to be a multigenetic disease.

Adverse pregnancy outcomes and inherited thrombophilia

2018 ◽  
Vol 46 (4) ◽  
pp. 411-417 ◽  
Author(s):  
Dominik Dłuski ◽  
Radzisław Mierzyński ◽  
Elżbieta Poniedziałek-Czajkowska ◽  
Bożena Leszczyńska-Gorzelak
Keyword(s):  
Pregnant Women ◽  
Pregnancy Outcomes ◽  
Protein C ◽  
Antithrombin Iii ◽  
Activated Protein C ◽  
Protein S ◽  
Adverse Pregnancy Outcomes ◽  
Control Group ◽  
Inherited Thrombophilia ◽  
Adverse Pregnancy

Abstract Aim: (1) To evaluate the prevalence of inherited thrombophilia in pregnant women with adverse pregnancy outcomes: intrauterine growth retardation (IUGR), preeclampsia (PE) and placental abruption. (2) To assess the impact of inherited thrombophilia on the nature of obstetric complications. (3) To assess levels of protein S, protein C, antithrombin III and homocysteine in pregnant women with adverse pregnancy outcomes. Subjects and methods: The study comprised 162 pregnant women. The patients were divided into three test groups and one control group. In all 162 patients the following tests were completed: activated protein C resistance (APC-R), the level of free protein S, activity of protein C, antithrombin III and the level of homocysteine. The data were statistically analyzed via χ2 of independence or homogeneity test. Results: In 32 of 162 patients participating in clinical research thrombophilia was diagnosed (10 patients with APC-R, 21 patients with protein S deficiency, one patient with hyperhomocysteinemia): seven patients belonged to the control group and 25 patients had diagnosed adverse pregnancy outcomes (P=0.04). In 32 patients with diagnosed thrombophilia, level of protein S was decreased (P=0.04). Protein S deficiency was diagnosed, when level of protein S was lower than 30% in the second trimester and lower than 24% in the third trimester. The incidence of activated protein C resistance caused by the mutation of factor V Leiden was in six patients (5.9%) with adverse pregnancy outcomes, and in four patients (6.6%) from the control group. Results were not statistically significant. No protein C deficiency was diagnosed (diagnosis: level<60%), but in 50% of patients with thrombophilia level of protein C was over the norm (P=0.02). The level of antithrombin III was often decreased in patients with preeclampsia – (32.4%), then in the other patients – (17.2%) (P=0.04), but no patient was diagnosed with antithrombin III deficiency (diagnosis: level<60%). Conclusions: Tests for thrombophilia should be carried out in women with adverse pregnancy outcomes in their history, who are planning pregnancy, to start anticoagulant prophylaxis. Our study supports the thesis that tests for thrombophilia should be carried out in women with a history of adverse pregnancy outcomes and who are planning a pregnancy to start anticoagulant prophylaxis.

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