Ga. Skarja et al., Protein and platelet interactions with thermally denatured fibrinogen and cross-linked fibrin coated surfaces, BIOMATERIAL, 19(23), 1998, pp. 2129-2138
In this work the hypothesis that a mature, cross-linked fibrin clot, pre-fo
rmed on a biomaterial, may be relatively nonthrombogenic was investigated.
A cross-linked fibrin layer was formed on polyethylene which had been preco
ated with thermally denatured fibrinogen. Plasma protein adsorption and pla
telet interactions with the cross-linked fibrin and denatured fibrinogen su
rfaces were investigated. The adsorption of albumin, fibrinogen, and fibron
ectin from plasma was measured. For all three proteins, the cross-linked fi
brin surface exhibited much higher levels of adsorption than either the the
rmally denatured fibrinogen or the polyethylene surface. Vroman peaks were
observed for fibrinogen and fibronectin on polyethylene but not on the cros
s-linked fibrin and thermally denatured fibrinogen materials. In dilute pla
sma the thermally denatured fibrinogen surface showed considerable resistan
ce to protein adsorption. However, at plasma concentrations greater than ab
out 5% normal, this protein resistance was apparently lost. Platelet intera
ctions (adhesion and release of granule constituents from adherent platelet
s) using suspensions of washed platelets in the presence of red cells were
investigated at shear rates of 50, 300, and 525 s(-1) using a cone and plat
e apparatus. The levels of platelet adhesion on the different surfaces were
in the order: adsorbed fibrinogen > cross-linked fibrin > thermally denatu
red fibrinogen = polyethylene. Platelets on the cross-linked fibrin surface
also showed high levels of release indicating significant platelet activat
ion. Scanning electron microscopic observations were in agreement with the
platelet adhesion and release data, showing only a few (but well-spread) ad
herent platelets on the cross-linked fibrin surface. (C) 1998 Elsevier Scie
nce Ltd. All rights reserved.