Preseeding of human vascular cells in decellularized bovine pericardium scaffold for tissue-engineered heart valve: an in vitro and in vivo feasibility study.

Human vascular cells from saphenous veins have been used for cell seeding on the synthetic scaffolds for constructing tissue-engineered heart valve (TEHV). However, little is known about the seeding of human vascular cells on bovine pericardium, a potential natural scaffold for TEHV. This study was aimed to assess the basic in vitro and in vivo characteristics of the human vascular cells seeded on decellularized bovine pericardium. In vitro, bovine pericardium samples with cell seeding were inspected on day 7, 14, and 21 by histology, scanning electron microscopy, and immunohistochemistry. In vivo, experiments were performed in nude mice by bilateral dorsal incision for the implantation of decellularized bovine pericardium with and without cell seeding. Results demonstrated that a total of 8-10 × 10(6) cells were obtained within 4-5 wk by the primary co-culture, which were detected positive for von Willebrand factor, α-smooth muscle actin antibodies, and fibronectin, indicating the presence of endothelial cells, smooth muscle cells, and fibroblasts, respectively. In vitro, the seeded cells showed a steady increase of endothelial activity from day 1 to day 7 and remained stable until day 21. After 30 days of implantation in vivo, the cells on the decellularized bovine pericardium could differentiate directionally and show all the identities of human endothelial cells, smooth muscle cells, and fibroblasts. These results indicate that the human vascular cells from the saphenous vein are an optional cell source for seeding on decellularized bovine pericardium scaffold for constructing TEHV.