Surface Activation of Plasma Clotting: A Function of Hageman Factor

Abstract

Plasma which has been in contact with powdered asbestos shows a shorter clotting-time than untreated plasma, as measured in the Quick one-stage, standard and modified proconvertin, and partial thromboplastin time assays. Asbestos treatment was applied to a panel of normal and clotting-factor deficient plasmas, and all samples tested, except those lacking Hageman factor, showed shortened clotting-times. Hageman factor, purified from normal serum and added to either normal or clotting-factor deficient plasmas, shortened all clotting times below control values. Similar preparations from serum of Hageman deficient individuals were inactive. The similarity between asbestos activated plasmas and purified Hageman factor preparations, and the failure to demonstrate similar activity in Hageman deficient plasma, points to the primary role of Hageman factor in plasma surface activation. It is suggested that asbestos treatment may serve as a useful presumptive test for Hageman factor deficiency.