Table 1.

Preclinical studies with tissue-engineered grafts.

Study	Animal model	Cells seeded	Scaffold used	Outcome
Matsumura et al., 2003b	Dog	Allogenic BMMNCs	Copolymer of LA/CL covered by PLLA	TE-grafts were implanted into the vena cava. After up to 8 weeks, no stenosis was observed and cells on the grafts expressed endothelial and VSMc markers
Vincentelli et al., 2007	Lamb	Allogenic BMMNCs or MSCs	Decellularized porcine pulmonary conduits	TE-grafts were implanted into the pulmonary artery. After 4 months, both the valves were recolonized and re-endothe-lialized. BMMNC-valves were thicker and showed inflammatory cell infiltration, while MSC-valves displayed extracellular matrix and cell disposition close to those of native pulmonary valves
Brennan et al., 2008	Lamb	Autologous BMMNCs	PGA scaffolds covered by LA/CL	TE-grafts implanted as inferior vena cava (IVC) interposition grafts. After 6 months, grafts were patent and increased in volume, with no evidence of aneurysmal dilatation. They were histologically comparable to the native IVC
Roh et al., 2010	SCID/beige mice	Xenogenic human BMMNCs	PGA scaffolds covered by LA/CL	TE-grafts were implanted as inferior vena cava interposition grafts. After 24 weeks the original scaffold was degraded and substituted by organized layers of ECM, endothelial and smooth muscle cells, resembling the native IVC
Sutherland et al., 2005	Sheep	Autologous BM-MSCs	PGA/PLLA	The pulmonary valve was resected and TE-valve was implanted into the pulmonary artery. After 4 and 8 months grafts were histologically comparable to the native valve
Shinoka et al., 1995	Lamb	Allogenic ovine artery fibroblasts and ECs	PGA leaflets	The right posterior leaflet of the pulmonary valve was resected and replaced with a TE-valve leaflet. Absence of stenosis. Development of ECM with appropriate cellular architecture
Dohmen et al., 2006b	Sheep	Autologous ECs from jugular vein	Decellularized valve	Scaffold was implanted into the RVOT. After 6 months, there was no calcification, and histologically ECs and fibroblasts were observed
He et al., 2010	Rat	Xenogenic human skeletal muscle pericytes	Poly(ester-urethane) urea scaffolds	TE-grafts were implanted end-to-end into the abdominal aorta. After 8 weeks, pericytes evenly populated the graft. TE-grafts presented extensive tissue remodeling with organized layers of endothelial and smooth muscle cells, and collagen and elastin, resembling the native arterial conduit