PEGylation prevents bacteria-induced platelet activation and biofilm formation in platelet concentrates

Bacterial contamination of platelet concentrates represents the greatest post-transfusion infectious risk. Biofilm formation in this environment resulting from platelet-bacteria interactions can lead to non-uniform contaminant distribution and thus missed detection. As formation of platelet-bacteria aggregates is largely based on receptor-ligand interactions, we examined whether shielding these events would result in reduced biofilm formation by contaminant bacteria. We introduced methoxypoly(ethylene glycol) to covalently modify the platelet surface using a process termed 'PEGylation'. In the first study of its kind, we demonstrate that PEGylated platelet concentrates inoculated with Staphylococcus epidermidis display a significant reduction in bacterial binding and biofilm formation.