Cysteine proteinase procoagulant from amnion-chorion
SG Gordon, U Hasiba, BA Cross, MA Poole and A Falanga
Various coagulation abnormalities are associated with pregnancy. Several
investigators have suggested that there may be a unique procoagulant
associated with amniotic tissue and fluid. We identified a cysteine
proteinase from malignant tissue, cancer procoagulant, and had reason to
believe a similar proteinase may be present in amniotic tissue. Amniotic
fluid and extracts of amnion-chorion were purified by immunoaffinity
chromatography with an antibody that was developed to cancer procoagulant
antigen. The purified amnion-chorion procoagulant initiated clotting in
normal and factor VII-deficient citrated human plasma and directly
activated pure human factor X in a two-stage clotting assay. It was
inhibited by 1 mmol/L of iodoacetamide and 0.1 mmol/L of HgCl2, and the
procoagulant activity was activated by 10 mmol/L of KCN; these are classic
properties of cysteine proteinases. The pure amnion-chorion procoagulant
had the same mol wt and immunologic determinants as cancer procoagulant
from rabbit V2 carcinoma, as determined by crossed immunodiffusion,
suggesting that the same or very similar proteins were associated with both
tissues. Thus, this procoagulant may be derived from both undifferentiated
and dedifferentiated cells.
Volume 66,
Issue 6,
pp. 1261-1265,
12/01/1985
Copyright © 1985 by The American Society of Hematology
