Fibrinogen surface distribution correlates to platelet adhesion pattern on fluorinated surface-modified polyetherurethane

Department of Chemical Engineering and Applied Science, University of Toronto, Ont., Canada.
Biomaterials (Impact Factor: 8.56). 12/2005; 26(35):7367-76. DOI: 10.1016/j.biomaterials.2005.05.063
Source: PubMed


In previous work, it had been shown that platelet adhesion could be reduced by fluorinating surfaces with oligomeric fluoropolymers, referred to as surface-modifying macromolecules (SMMs). In the current study, two in vitro blood-contacting experiments were carried out on a polyetherurethane modified with three different SMMs in order to determine if altered platelet adhesion levels could be related to the pattern of adsorbed protein and more specifically to the manner in which fibrinogen (Fg) distribution occurs at the surface. In the first experiment, the materials were placed in whole human blood and the adherent platelets were viewed with high-resolution scanning electron microscopy (SEM). In a second experiment, the materials were incubated with human plasma with the absence of platelets. The plasma contained 5% fluorescent-Fg. The materials were then viewed with a fluorescence microscope and images were collected to define the distribution of high-density fluorescent-Fg areas. The SEM and fluorescent-Fg images were imported to Image Pro Plus imaging software to measure the area, length and circularity and a bivariate correlation test was conducted between the two sets of data. For area and length morphology parameters, there were high and significant correlations (r > 0.9, p < 0.05) between the platelets and Fg aggregates. The data suggest that the Fg distribution may serve as a predictor of platelet morphology/activation and provides insight into the non-thrombogenic character of biomaterials containing the fluorinated SMMs.

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    • "When a biomaterial is implanted in the human body, water and protein adsorption to surfaces typically occurs. Then, cells such as leucocytes and platelets contact biomaterial surfaces and are activated due to stimulation by cytokines and growth factors (Hussain et al 2004; Massa et al 2005). A common failure of a biomaterial arises from thrombogenesis, which is initiated by platelets’ adhesion onto artificial surface and activation. "
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