Cytotoxicity of PVPAC‐treated bovine pericardium: A potential replacement for glutaraldehyde in biological heart valves

Acellular biological tissues, including bovine pericardium (BP), have been proposed as biomaterial for tissue engineering. BP is usually modified chemically to improve mechanical and biological properties using glutaraldehyde, the standard reagent for preservation of fresh bioprosthetic materials. Glutaraldehyde-fixed BP (Glut-BP), the most widely used material in heart valve manufacture, has been associated with calcification in vivo. In an attempt to reduce this issue and maintain its biocompatibility, this study assesses the physical properties and cytotoxicity of lyophilized BP treated with poly (vinylpyrrolidone-co-acrolein) (PVPAC-BP), a novel copolymer, as a substitute for glutaraldehyde. For that, PVPAC-BP surface ultrastructure, elastic function, water uptake and tissue calcification were evaluated. For the analysis of biocompatibility, fibroblasts (3T3-L1) and endothelial cells (HUVEC) were cultured on PVPAC-BP, Untreated-BP and Glut-BP. Nitric oxide (NO) release assay, fluorescence and SEM images of endothelial cells adhered on scaffolds were also performed. As results, the data show some advantages of PVPAC-BP over the Glut-BP. The PVPAC-BP maintains partially the original ultrastructure and elastic properties, improves scaffold hydration, and presents less calcium phosphate deposits. The cells demonstrated strong attachment, high proliferation rate, and formation of a monolayer on PVPAC-BP. Attached cells were also able to release NO de-monstrating regular metabolism. In conclusion, PVPAC may be considered as a promising alternative to BP treatment improving the efficiency of cell attachment and proliferation and also avoid immunogenicity.