PROTEIN ADSORPTION AND BACTERIAL ADHESION TO BILIARY STENT MATERIALS

Four biliary stents inserted for relief of jaundice in patients with b iliary obstruction due to carcinoma of pancreatic head were examined f or the adsorption of biliary proteins and bacterial colonization, Fibr onectin and vitronectin (S-protein) were found to be the two main prot eins adsorbed on the inner surface of the stents, Biliary isolates inc luded Escherichia coli, Enterococcus faecalis, and Candida albicans. I n vitro studies were performed to clarify the kinetics of biliary prot ein and bacterial adhesion, Biliary drains of polytetrafluorethylene, polyethylene, polyurethane, and rubber were placed in a flow cell and perfused with human bile at 37 degrees C for 24 hr, The materials were subjected to either detection of adsorbed biliary proteins or perfusi on with H-3-labeled E. coli cells (1 x 10(6) cfu/ml). The results show that the adsorbed biliary proteins were detectable on the surface of biliary stents and able to enhance bacterial adhesion to the surface i n the first 24 hrs after the exposure of stent materials to bile, and that both the adsorption of biliary proteins and the adhesion of bacte rial cells were material- and strain-dependent. Furthermore, there was a clear correlation between the amount of adsorbed fibronectin and th e number of adherent bacteria. The results indicate that, in the clini cal situation, biliary proteins may be adsorbed on the surface of inse rted stents within a short time after insertion, and some of them may be used by bacterial cells as receptors for adhesion to the surface, a nd thus involved in the process of bacterial adhesion. (C) 1996 Academ ic Press, Inc.