Effects of Seitz filtration on Plasma Trace Proteins Concerned with Blood Coagulation: A Quantitative Study

Abstract

Two liters of bovine plasma were filtered through a 20% Seitz asbestos pad of 14 cm. diam. The first 100 ml. of filtrate, and then each subsequent 200 ml. were collected as separate fractions and assayed for prothrombin, fibrinogen, antithrombin-III, Ac-globulin, SPCA precursor, heparin co-factor, antithrombin-IV and the antihemophilic factor. The concn. of prothrombin and fibrinogen was markedly decreased in early fractions but rapidly returned to normal in subsequent fractions. SPCA precursor seemed to adsorb in a manner similar to prothrombin and fibrinogen, although assay results were somewhat erratic. It is doubted that the Seitz filter offers much opportunity for the satisfactory separation of prothrombin and SPCA precursor. Antithrombins III and IV did not appear to be adsorbed to any appreciable extent. Ac-globulin and the heparin co-factor responded to Seitz filtration in an unexpected way. The concns. of these factors in some of the fractions of filtered plasma appeared to be considerably higher than their concns. in un-filtered plasma. The hypothesis is offered that these seeming increases in concn. are associated with removal of inhibitor material. The antihemophilic factor apparently also increased in Seitz filtered plasma, but the results do not permit the drawing of any definite conclusions.