Some Properties of Platelet Cofactor I Concentrates of Bovine Origin

Summary

Platelet cofactor I preparations from bovine plasma were studied from the viewpoint of stability in the presence of chemicals selected strategically. The preparations were of high quality having about 86 per cent of the protein as one component by ultracentrifuge analysis. The activity was easily destroyed with hydrogen peroxide, sodium sulfite, phenylhydrazine, formalin, acetone, and by the process of freeze drying. The activity was not lost in the presence of oxygen, ascorbic acid, cysteine, merthiolate, parachloromercuribenzoate or 0.5 per cent phenol. In the native plasma the activity is not adsorbed on barium carbonate, barium sulfate, or magnesium hydroxide. Nor is it destroyed by ether; but, in purified form it is adsorbed on these adsorbants and is destroyed by ether. In the purified preparations the activity was not adsorbed on IRC-50 resin thus making it possible to use this adsorbant to remove any thrombin that might be added to a platelet cofactor I preparation. By this technic it was possible to show that thrombin alone does not easily destroy platelet cofactor I activity.

^* This investigation was supported by a research grant H-2026 from the National Heart Institute, National Institutes of Health.

• References

• (1) Seegers W. H, Mammen E, Lee J. M, Landaburu R. H, Cho M. H, Baker W. J, Shepard R. S. Further studies on the purification of platelet cofactor I. In Hemophilia and other Hemorrhagic States. University of North Carolina Press; Chapel Hill: Edited by Brinkhous K. M. 1959
• (2) Seegers W. H, Landaburu R. H, Holburn R. R, Tocantins L. M. Clotting of hemophilic blood with purified platelet cofactor I, platelet factor 3 and threone. Proc. Soc: exp. Biol. (N. Y.) 95: 583 1957;
• (3) Johnson J. F, Mammen E. F, Seegers W. H. Prothrombin utilization following addition of platelet cofactor I concentrates to hemophilic plasma. Thromb. Diath. haem. 3: 588 1959;
• (4) Johnson S. A. Activation of purified prothrombin with hemophilic plasma. Amer. J. Clin. Path. 23: 875 1953;
• (5) Seegers W. H, Smith H. P. Factors which influence the activity of purified thrombin. Amer. J. Physiol. 137: 348 1942;
• (6) Johnson S. A, Seegers W. H. Platelet cofactor I activity in the hemophilias. In Hemophilia and Hemophilioid Diseases. University of North Carolina Press; Chapel Hill: 1957. Brinkhous K. M. editor.
• (7) Seegers W. H, Landaburu R. H, Fenichel R. L. Isolation of platelet cofactor I from plasma and some properties of the preparation. Amer. J. Physiol. 190: 1 1957;
• (8) Johnson S. A, Seegers W. H. Studies on the plasma defect in hemophilia. Rev. Héinat. 9: 529 1954;
• (9) Seegers W. H. The purification of prothrombin. Record. Chem. Progr. 13: 143 1952;
• (10) Wright I. S. Nomenclature of blood clotting factors. Thromb. Diath. haem. 3: 435 1959;
• (11) Graham J. B, Barrow E. M. The pathogenesis of hemophilia. J. exp. Med. 106: 273 1957;