Interactions of thermally denatured fibrinogen on polyethylene with plasma proteins and platelets

During the investigation of fibrin deposition onto hydrophobic polymers in contact with human blood, a model was developed in which fibrinogen was denatured and irreversibly coated onto a polyethylene surface by heating to 70°C for 10 min. The denatured fibrinogen‐polyethylene surface is resistant to fluid wall shear rates of up to 550 s−1 and the fibrinogen does not desorb in the presence of plasma proteins. Compared to uncoated polyethylene, little albumin or fibrinogen adsorbs to heat‐denatured fibrinogen. Thrombin binds to the denatured fibrinogen‐coated polyethylene with low affinity and also acts on the surface‐bound denatured fibrinogen and cleaves fibrinopeptide A (FPA) quantitatively. Washed, 51Cr‐labeled platelets do not adhere to the thermally denatured fibrinogen at either low or high shear rates compared to surfaces coated with undenatured fibrinogen (p < 0.01). These observations support the role of the D domain of fibrinogen in platelet adhesion because this is the region that is denatured by heating. In contrast, the E domain of fibrinogen is not altered by heating to 70°C and hence remains susceptible to thrombin and/or plasmin cleavage. The characteristics of this surface are such that it can be used to develop fibrin‐coated surfaces for use in studies of thrombus formation on artificial surfaces. © 1992 John Wiley & Sons, Inc.