Background: This study was performed to evaluate the possibility of seeding No-React®-treated bovine small-diameter internal mammary arteries (SIMAs) and to record any improvement in patency rate.
Material/Methods: During the in vitro study, 12 seeded SIMAs were divided into two groups; group I (n=6) was endothelial cell (EC) seeded and group II (n=6) EC seeded after pre-coating with fibrin glue to evaluate the binding capacity. During the in vivo part of the study, eight juvenile sheep received either a seeded or a non-seeded SIMA. In the seeded group (n=3), a piece of jugular vein was harvested to culture autologous ECs. SIMA grafts were coated and seeded in a special bioreactor. In the control group (n=5), non-seeded SIMA grafts were implanted. No anti-coagulation was administered. Explantation was performed at three and six months post-implantation. Grafts were evaluated by gross examination, histology, and immunohistochemistry.
Results: By inserting two million ECs in the in vitro study, the seeding density in group I was 1.29±0.09×10[sup]5[/sup] cells/cm[sup]2[/sup] and 2.27±0.17×10[sup]5[/sup] cells/cm[sup]2[/sup] in group II (p<0.003). In the in vivo study the mean EC density of the implanted seeded grafts was 2.35±0.04×105 cells/cm². At explantation, the seeded grafts showed less infl ammatory reaction and a higher patency rate compared with the non-seeded grafts.Histology showed a monolayer of ECs on the inner surface of seeded SIMAs at follow-up.
Conclusions: Seeding of No-React®-treated SIMA arterial grafts with autologous ECs increases the patency
rate.

Keywords: Aging - physiology, Cattle, Cell Culture Techniques - methods, Coculture Techniques - methods, Endothelial Cells - cytology, Mammary Glands, Animal - blood supply, Sheep