(377d) Regenerative Artificial Vascular Graft Using Acellular Scaffold

Tissue-engineered vascular grafts may have the advantage of growth potential and anti-infection compared with the current artificial grafts. Biodegradable materials such as polylactide and/or polyglycolide are commonly used for the regenerative scaffolds and some have already been applied for the clinical use. However, since these materials are degraded by a simple hydrolysis, they may not be applicable to the arterial scaffolds necessary to have mechanical strength until their recellularization. Regenerative vascular grafts made of collagenous tissue have been developed by an elimination of elastin and cellular components from living tissues. Porcine vascular tissues were isolated and washed by PBS. They were crosslinked by glutaraldehyde (GA) or in a vacuum oven followed by elastase digestion. They were then subjected to the histological observation, DNA and phospholipids assay, and biomechanical study. There were no cells and elastin fibers observed in the tissues treated by 0.01% GA for 24 hrs followed by elastase digestion for 12 hrs. The amounts of DNA and phospholipids were lower than 5% of the native tissue. Both the breaking strength and elastic modulus of the treated aortic graft were lower than those of the native aorta but higher than of the native pulmonary artery. The residual phospholipids and denatured elastin fibers may cause the calcification after the graft transplantation. This process eliminates these substances and may be useful for having regenerative scaffolds for the vascular tissue regeneration.