Decellularized aorta of fetal pigs as a potential scaffold for small diameter tissue engineered vascular graft.

Background: For cardiovascular tissue engineering, acellularized biomaterials from pig have been widely investigated. Our purpose was to study mechanical properties and biocompatibility of decellularized aorta of fetal pigs (DAFP) to determine its potential as scaffold for small diameter tissue engineered vascular graft.

Methods: Descending aorta of fetal pigs was removed cells using trypsin, ribonuclease and desoxyribonuclease. Mechanical properties of DAFP were evaluated by tensile stress-strain and burst pressure analysis. Assessment of cell adhesion and compatibility was conducted by seeding porcine aortic endothelial cells. To evaluate biocompatibility in vivo, DAFP was implanted subcutaneously into adult male Sprague Dawley rats for 2, 4 and 8 weeks.

Results: Histochemistry and scanning electron microscopy examination of DAFP revealed well-preserved extracellular matrix proteins and porous three-dimensional structures. Compared with fresh aorta, DAFP had similar ultimate tensile strength, axial compliance and burst pressure. Cell culture studies in vitro showed that porcine aortic endothelial cells adhered and proliferated on the surfaces of DAFP with excellent cell viability. Subdermal implantation demonstrated that the DAFP did not show almost any immunological reaction and exhibited minimal calcification during the whole follow-up period.

Conclusion: The DAFP has the potential to serve as scaffolds for small diameter tissue engineered vascular graft.