Summary
The effect of Placental Protein 5 (PP5) on thrombin-induced coagulation of diluted fibrinogen is described. In contrast to previous reports which failed to demonstrate antithrombin-like activity for PP5 on synthetic substrates, we show in this study that PP5 inhibits thrombin activity in a dose-dependent manner. PP5 acts thus in a very similar way to antithrombin III (ATIII). Although PP5 binds to heparin, it does not show any heparincofactor activity. Whereas catalytic amounts of heparin accelerate greatly the inhibitory effect of ATIII, no accelerating effect of heparin on PP5 could be observed under the same conditions.
In spite of its anti-thrombin activity, PP5 cannot be considered as a pregnancy-analogue of ATIII, as it lacks the heparin-cofactor activity.
Similar content being viewed by others
References
Bohn H, Winckler W (1977) Isolierung und Charakterisierung des Plazenta-Proteins PP5. Arch Gynäkol 223: 179–186
Conard J, Brosstad F, Lie Larsen M, Samama M, Abildgard U (1983) Molar antithrombin concentration in normal human plasma. Haemostasis 13: 363–368
Jones GRD, Davey MW, Teisner B, Grudzinskas JG (1981) Specific interaction between placental protein 5 and thrombin. Clin Chim Acta 114: 75–82
Obiekwe B, Pendlebury DJ, Gordon YB, Grudzinskas JG, Chard T, Bohn H (1979) The radioimmunoassay of placental protein 5 and circulating levels in the third trimester of normal pregnancy. Clin Chim Acta 95: 509–516
Ranta T, Siiteri JE, Koistinen R, Salem HT, Bohn H, Koskimies AI, Seppälä M (1981) Human seminal plasma contains a protein that shares physicochemical and immunochemical properties with placental protein 5 from the human placenta. J Clin Endocrinol Metab 53: 1087–1089
Salem HT, Obiekwe BC, Al-Ani ATM, Seppälä M, Chard T (1980) Molecular heterogeneity of placental protein 5 (PP5) in late pregnancy serum and plasma: evidence for a heparin-PP5 polymer. Clin Chim Acta 107: 211–215
Salem HT, Seppälä M, Chard T (1981) The effect of thrombin on serum placental protein 5 (PP5): is PP5 the naturally occurring antithrombin III of the human placenta? Placenta 2: 205–210
Seppälä M, Wahlström T, Bohn H (1979) Circulating levels and tissue localization of placental protein five (PP5) in pregnancy and trophoblastic disease: absence of PP5 expression in the malignant trophoblast. Int J Cancer 24: 6–10
Seppälä M, Tenhunen A, Koskimies AI, Wahlström T, Koistinen R, Stenman UH (1984) Hyperstimulated human preovulatory follicular fluid contains placental protein 5 (PP5). Fertil Steril 41: 62–65
Siiteri JE, Koistinen R, Salem HT, Bohn H, Seppälä M (1982) Placental protein 5 is related to blood coagulation and fibrinolytic systems. Life Sci 30: 1885–1891
Wahlström T, Bohn H, Seppälä M (1982) Immunochemical demonstration of placental protein 5 (PP5)-like material in the seminal vesicle and the ampullar part of vas deferens. Life Sci 31: 2723–2725
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Meisser, A., Bischof, P. & Bohn, H. Placental protein 5 (PP5) inhibits thrombin-induced coagulation of fibrinogen. Arch. Gynecol. 236, 197–201 (1985). https://doi.org/10.1007/BF02133936
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02133936