Morphologic characteristics of adsorbed human plasma proteins on vascular grafts and biomaterials

Protein adsorption on the surfaces of clinically significant prosthetic vascular graft materials from human whole blood was independent of plasma concentration as determined morphologically by use of immunogold labels. Some proteins, such as fibrinogen, adsorbed in a multilayer pattern on expanded polytetrafluoroethylene and had a preference for particular surface features of the polymer. Other proteins, such as Hageman factor (factor XII), showed diffuse adsorption patterns. Physiologically significant proteins that have not been well studied, such as immunoglobulin G and factor VIII, adsorbed readily to the surface of expanded polytetrafluoroethylene. This finding may be significant since adsorbed proteins may activate coagulation mechanisms and immunologic responses, including platelet and monocyte adhesion and activation. Any human blood protein for which an antibody has been developed can be studied by use of this technique.