Polyelectrolyte multilayer film on decellularized porcine aortic valve can reduce the adhesion of blood cells without affecting the growth of human circulating progenitor cells.

Polyelectrolyte multilayer film modification could be an effective method to reduce the immunological and inflammatory response of the xenogeneic scaffold in vivo, and may also be applied to tissue-engineered heart valve in contact with blood. The objectives of this study are to test heparin-chitosan multilayer film as an antithrombotic coating reagent for decellularized aortic heart valve and the biocompatibility of the modified valvular surface. The adhesion and geometric deformation of platelets were demonstrated by scanning electron microscopy. The quantitative assay of platelet activation was determined by measuring the production of soluble P-selectin. Moreover, the leukocytes' adhesion, erythrocyte hemolysis, and whole blood clotting time studies were performed to gain information on the hemocompatibility of this biomaterial. Human-blood-derived endothelial progenitor cells (EPCs) were cultured and the adhesion and growth of EPCs on the surface-modified PDAV were assessed. The results showed that heparin-chitosan multilayer film could be coated on the decellularized valvular scaffolds, and improved their hemocompatibility with respect to a substantial reduction of platelet adhesion and activation. The modified valve also significantly reduced leukocytes adhesion, erythrocyte hemolysis, and whole blood clotting time. Seeding with EPCs achieved a confluent monolayer on the surface of the decellularized matrix. The in vitro studies performed in this work suggest that it may be reasonable to use heparin-chitosan multilayer film as a means of surface modification to improve the blood compatibility of decellularized valvular scaffold.