EFFECT OF SINGLE-CHAIN AND 2-CHAIN HIGH-MOLECULAR-WEIGHT KININOGEN ONADSORPTION OF FIBRINOGEN FROM BINARY-MIXTURES TO GLASS AND SULFONATEDPOLYURETHANE SURFACES

The adsorption of fibrinogen from a single protein solution and from b inary mixtures of fibrinogen and high-molecular-weight kininogen (HK) to glass and four sulfonated polyurethane surfaces is reported. The ef fect of the single-chain (SCHK) and two-chain (TCHK) forms of HK on fi brinogen adsorption was investigated. Using radiolabeling methods, fib rinogen adsorption from a series of mixtures having the same weight ra tio of fibrinogen to HK as in plasma (50:1), but varying in total conc entration, was measured. Fibrinogen adsorption from the mixtures was r educed on all surfaces compared to the single-protein solution, confir ming the highly surface-active nature of this protein. However, except for glass, there was no significant difference between the SCHK and T CHK forms. Polyacrylamide gel electrophoresis and immunoblotting analy sis of the proteins eluted from the surfaces after contact with the fi brinogen-SCHK solutions indicated that although intact SCHK was essent ially conserved, some transformation of SCHK to TCHK on the surface oc curred during the course of the experiment. It is hypothesized that in purified form, in which HK is not complexed to prekallikrein or facto r XI, the surface-binding domain is more available than in the complex ed forms which are present in plasma. If so, then the removal of brady kinin by kallikrein, as occurs in generating TCHK, may not be required for the expression of surface-binding domain activity. (C) 1997 John Wiley & Sons, Inc.