Ulvan mediated VE cadherin antibody and REDV peptide co-modification to improve endothelialization potential of bioprosthetic heart valves

An aging population and a rapid increase in the incidence of degenerative valve diseases have led to greater use of bioprosthetic heart valves (BHVs). The durability of glutaraldehyde cross-linked bioprostheses currently available for clinical use is poor due to calcification, coagulation, and degradation. Decellularization can partially reduce calcification by removal of xenogenic cells, but can also lead to thrombosis, which can be addressed by further surface modification. The natural sulfated polysaccharide ulvan possesses antithrombotic and anti-inflammatory properties, and can behave as a heparinoid to immobilize proteins through their heparin binding sites. VE-cadherin antibody and the Arg-Glu-Asp-Val (REDV) peptide can facilitate selective endothelial cell attachment, adhesion and proliferation. In this study, we functionalized decellularized porcine pericardium (DPP) with ulvan, REDV, and VE-cadherin antibody (U-R-VE). Ulvan was covalently modified to act as a protective coating and spacer for VE-cadherin antibody, and to immobilize REDV. In in vitro tests, we found that functionalization significantly and selectively promoted adhesion and growth of endothelial cells while reducing platelet adhesion, inflammation, and in vitro calcification of DPPs. In an in vivo subdermal implantation model, U-R-VE modified DPP exhibited greater endothelialization potential and biocompatibility compared with unmodified pericardium. Thus, U-R-VE modification provides a promising solution to the problem of preparing BHVs with enhanced endothelialization potential.