Hierarchical-structured bacterial cellulose/potato starch tubes as potential small-diameter vascular grafts

To achieve long-term patent small-diameter (<6 mm) vascular implants, biomimetic vascular grafts have gained much attention in promoting in situ blood vessel regeneration. In this study, hierarchical-structured bacterial cellulose/potato starch (BC/PS) composites were biosynthesized by the addition of swollen PS. Investigations on the physicochemical properties of BC/PS composites showed that the properties could be improved and tailored by the addition of swollen PS. The composites displayed a morphology, water content, thermal properties, mechanical properties, and biocompatibility appropriate for vascular tissue engineering. Most importantly, the BC/PS grafts, with a dense inner surface and a circumferential macroporous outer layer, possessed 75% patency and promoted rapid blood vessel regeneration in in vivo assessment on rabbits, with complete endothelium monolayer, organized smooth muscle cells, rich new capillaries, and deposited extracellular matrix. Collectively, these findings demonstrate that hierarchical-structured BC/PS tubes hold great promise as artificial small-diameter vascular grafts.