Silk fibroin vascular graft: a promising tissue-engineered scaffold material for abdominal venous system replacement
Sho Kiritani, Junichi Kaneko, Daisuke Ito, Masaaki Morito, Takeaki Ishizawa, Nobuhisa Akamatsu, Mariko Tanaka, Takuya Iida, Takashi Tanaka, Ryo Tanaka, Tetsuo Asakura, Junichi Arita, Kiyoshi Hasegawa
Abstract
No alternative tissue-engineered vascular grafts for the abdominal venous system are reported. The present study focused on the development of new tissue-engineered vascular graft using a silk-based scaffold material for abdominal venous system replacement. A rat vein, the inferior vena cava, was replaced by a silk fibroin (SF, a biocompatible natural insoluble protein present in silk thread), tissue-engineered vascular graft (10 mm long, 3 mm diameter, n = 19, SF group). The 1 and 4 -week patency rates and histologic reactions were compared with those of expanded polytetrafluoroethylene vascular grafts (n = 10, ePTFE group). The patency rate at 1 and 4 weeks after replacement in the SF group was 100.0% and 94.7%, and that in the ePTFE group was 100.0% and 80.0%, respectively. There was no significant difference between groups (p = 0.36). Unlike the ePTFE graft, CD31-positive endothelial cells covered the whole luminal surface of the SF vascular graft at 4 weeks, indicating better endothelialization. SF vascular grafts may be a promising tissue-engineered scaffold material for abdominal venous system replacement.