Endogenous basic fibroblast growth factor for endothelialization due to angiogenesis in fabric vascular prostheses

Angiogenesis by basic fibroblast growth factor (bFGF) is important for endothelialization in vascular prostheses and is significant from shortly after implantation. Canine adipose tissue was resected, minced into fragments, and suspended. This mixture was sieved through the wall of a fabric vascular prosthesis. Tissue-fragmented grafts (TF-grafts, 6 mm internal diameter, 6 cm long) were implanted into the abdominal aortae of four dogs, and four preclotted grafts were used as control subjects. Grafts were removed at 1-7 days after implantation. Removed grafts were evaluated microscopically, immunohistologically, and by scanning electron microscope. At day 1, a thrombus layer was on the TF-graft lumen. At day 3, cell proliferation and migration were observed. At day 5, endothelial-like cells were extending onto the luminal thrombus. Cell proliferation around the fragments was active, and those cells were bFGF positive. In the control subjects, at day 7, the perigraft tissue was bFGF positive, whereas no endothelialization on the lumen or no capillary infiltration into the graft wall was observed. Furthermore, bFGF was negative in the sites of thrombus and infection. These results demonstrate that endogenous bFGF is important for endothelialization due to angiogenesis in fabric vascular prostheses, whereas thrombus and infection might have a negative effect.