Immunochemical detection by specific antibody to thrombin of prothrombin conformational changes upon adsorption to artificial surfaces

Abstract

Polyclonal antihuman α-thrombin antibodies produced in rabbits reacted minimally (95% purity) was shown to be significantly enhanced. On PVC, the molar ratios of antibody IgG to thrombin/prothrombin approached the same level as that of antibody IgG to thrombin/thrombin when thrombin was adsorbed to the same material. The analyses of antigen–antibodies interaction, in solution with a direct binding assay by immune precipitation at high-speed centrifugation (160,000 g, 30 min), and on solid-phase PVC, were accomplished by use of double-labeling technique, i.e., ¹³¹I-thrombin (or ¹³¹I-prothrombin) and ¹²⁵I-antibody IgG to thrombin. The results appear to suggest that prothrombin adsorption to PVC has resulted in some molecular conformational changes so that immunologically the adsorbed prothrombin resembles that of adsorbed thrombin on the same PVC surface.