Effects in vitro of bovine and human antihemophilic globulins on substrate plasmas

¹ Charlotte Drake Cardeza Foundation, Jefferson Medical College, Philadelphia, Pennsylvania

Greater clot-promoting activity has been claimed for antihemophilic globulin (AHG) preparations from bovine plasma than for those from normal human plasma. This has been attributed to an actual higher amount of the globulin in bovine plasma. A comparison was made of the effects of bovine and human antihemophilic globulins, collected and prepared in the same manner, on the rate of clotting of not only normal and hemophilic human plasmas but on bovine plasma as well. AHG was prepared from citrated plasma by dilution, acidification, and solution of the washed precipitate in normal saline. While bovine AHG is more effective than human AHG in accelerating the clotting of normal and hemophilic human plasmas, human AHG has a greater effect on bovine plasma than does bovine AHG. Moderate dilution of the plasma substrate enhances the clot-accelerating action of the homologous AHG. The response of a plasma substrate to AHG preparations suggests the presence in plasma of species-specific antagonists which reduce the clot-promoting activity of the homologous AHG, but which are less effective against preparations from heterologous sources.

Key Words: hemophilia A • AHG • AHF • factor VIII • comparison of antihemophilic globulins, bovine and human • in vitro effects of bovine and human AHGs on hemophilic plasma clot-promoting activity • plasma species-specific antagonists homologous and heterologous clotting systems

Submitted on June 21, 1963