Cysteine proteinase procoagulant from amnion-chorion

Area of Science:

• Biochemistry
• Hematology
• Obstetrics

Background:

• Pregnancy is associated with coagulation abnormalities.
• A unique procoagulant in amniotic tissue and fluid has been hypothesized.
• Cancer procoagulant, a cysteine proteinase, is found in malignant tissue.

Purpose of the Study:

• To identify and characterize a potential procoagulant in amniotic tissue.
• To investigate its relationship with cancer procoagulant.

Main Methods:

• Purification of amnion-chorion procoagulant using immunoaffinity chromatography.
• Assays to determine clotting initiation and factor activation.
• Characterization of enzyme properties (inhibition, activation) and molecular weight.
• Immunological comparison with cancer procoagulant.

Main Results:

• A cysteine proteinase was purified from amnion-chorion extracts.
• The purified procoagulant initiated clotting in normal and factor VII-deficient plasma.
• It directly activated human factor X.
• Enzyme properties and immunological determinants were identical to cancer procoagulant.

Conclusions:

• A cysteine proteinase, functionally and immunologically similar to cancer procoagulant, is present in amniotic tissue.
• This suggests a shared origin or pathway between procoagulants in amniotic and malignant tissues.
• The findings may have implications for understanding coagulation during pregnancy and in cancer.