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Published on: November 28, 2019
Protein C, protein S, and thrombomodulin in amniotic fluid. A preliminary study
Mieczysław Uszyński1, Ewa Zekanowska, Marcin Kotzbach
1Department of Propedeutics of Medicine, Nicolaus Copernicus University, Collegium Medicum in Bydgoszcz, Poland. kizproped@cm.umk.pl
Insights
Protein C (PC), protein S (PS), and thrombomodulin (TM) are found in amniotic fluid. However, their low concentrations suggest they may not prevent blood clotting in the amniotic fluid during pregnancy.
Area of Science:
- Biochemistry
- Obstetrics
- Hematology
Background:
- The protein C anticoagulant system, comprising protein C (PC), protein S (PS), and thrombomodulin (TM), is crucial for preventing thrombosis during pregnancy.
- The presence and role of this anticoagulant pathway within amniotic fluid remain largely uncharacterized.
Purpose of the Study:
- To investigate the presence of protein C (PC), protein S (PS), and thrombomodulin (TM) in human amniotic fluid.
- To determine if these anticoagulant components are physiological constituents of amniotic fluid.
Main Methods:
- Study involved 50 pregnant women and 25 non-pregnant controls.
- Amniotic fluid and maternal blood samples were collected at the end of the first stage of labor.
- Immunoenzymatic methods were used to quantify PC, PS, and TM levels.
Main Results:
- Measurable levels of PC, PS, and TM antigens were detected in all amniotic fluid samples.
- Concentrations of PC and PS in amniotic fluid were significantly lower (P<0.0001) than in maternal plasma.
- TM concentration in amniotic fluid was 63.92% of that found in maternal blood (P<0.001).
Conclusions:
- Protein C, protein S, and thrombomodulin are confirmed as physiological components of amniotic fluid.
- The significantly lower concentrations of these proteins in amniotic fluid suggest they may be insufficient to counteract its procoagulant activity.
Objectives:
The main components of protein C anticoagulant system are protein C (PC), protein S (PS) and thrombomodulin (TM); the system plays a protective role in pregnancy, mainly because it prevents the utero-placental circulation from local thrombosis. It is unknown whether the protein C anticoagulant pathway exists in amniotic fluid. The aim of the present study is to find out whether these three components are present in amniotic fluid.
Study Design:
The study group consisted of 50 parturients with an uneventful pregnancy and birth and 25 non-pregnant controls. Amniotic fluid and blood were sampled at the end of the 1st stage of labor. PC, PS and TM were measured by immunoenzymatic method.
Results:
All the samples of amniotic fluid contained measurable amounts of antigens of PC, PS and TM, although their concentrations were significantly lower than in the mother's blood: (i) The concentration of PC in amniotic fluid was 6.24+/-3.50% and PS 2.40+/-1.64%, while in the mothers' plasma it was 138.26+/-12.38% and 93.15+/-13.24%, respectively (P<0.0001). (ii) TM concentration in amniotic fluid constituted 63.92% of the concentration in the mother's blood (2.71+/-1.21 ng/mL vs. 4.24+/-0.88 ng/mL, P<0.001).
Conclusion:
Protein C, protein S and thrombomodulin are physiological constituents of the amniotic fluid. As their concentrations are low, it is reasonable to assume that they cannot counterbalance the procoagulant activity of amniotic fluid.