Biomimetic modification of poly(vinyl alcohol): Encouraging endothelialization and preventing thrombosis with antiplatelet monotherapy

摘要

Poly(vinyl alcohol) (PVA) has shown promise as a biomaterial for cardiovascular application. However, its antifouling properties prevent in vivo endothelialization. This work examined the endothelialization and thrombogenicity of modified PVA with different concentrations of proteins and adhesion peptides: collagen, laminin, fibronectin, GFPGER, YIGSR, and cRGD. Material surface properties were quantified, and the endothelialization potential was determined with human endothelial colony forming cells. Additionally, platelet attachment was assessed in vitro with human platelet rich plasma, and promising samples were tested in an ex vivo shunt model. This well-established arteriovenous shunt model was used with and without clinically-relevant antiplatelet therapies, specifically acetylsalicylic acid (ASA) with and without clopidogrel to examine the minimum necessary treatment to prevent thrombosis. Collagen, laminin, and GFPGER biomolecules increased endothelialization, with GFPGER showing the greatest effect at the lowest concentrations. GFPGER-PVA tubes tested under whole blood did exhibit an increase in platelet (but not fibrin) attachment compared to plain PVA and clinical controls. However, application of ASA monotherapy reduced the thrombogenicity of GFPGER-PVA below the clinical control with the ASA. This work is significant in developing cardiovascular biomaterials increasing endothelialization potential while reducing bleeding side effects by using an antiplatelet monotherapy, typical of clinical patients.