Smooth muscle and endothelial cell behaviour on degradable copolyetheresterurethane films

Stent thrombosis and restenosis after drug-eluting stent (DES) implantation remains a relevant problem in the cardiovascular field. The polymer-based biomaterial (e.g. stent coating) requirements are comprehensive, since the polymeric material ideally should ensure an effective re-endothelialization by recruiting endothelial cells (EC) and endothelial progenitor cells (EPC). Simultaneously, the polymer should effectively prevent adherence of smooth muscle cells (SMC) and thereby inhibiting restenosis. The aim of this study was to gain a basic understanding on the interaction of SMC and human umbilical vein endothelial cells (HUVEC) with nonporous polymer films. A multifunctional copolyetheresterurethane (PDC) was chosen as candidate material: PDC consists of poly(p-dioxanone) (PPDO) and poly(ε-caprolactone)-segments (PCL). In our study it was compared to the degradable PPDO homopolymer and poly(vinylidene fluoride-co-hexafluoropropene) (PVDF), an established coating material of DES in clinical applications intended for longterm applications. The films were analyzed according to their thermomechanical and surface properties before being examined in contact with HUVEC and SMC concerning cell viability, proliferation and adhesion. Experimental results showed that adhesion could be improved for HUVEC on PDC compared to PPDO and PVDF. In contrast, SMC attachment is largely suppressed on PDC polymeric films indicating a cell-specific response of HUVEC towards PDC. In conclusion, PDC represents a promising candidate material for future cardiovascular applications like e.g. biodegradable (PDC) stent coatings.