Decellularization, cross-linking and heparin immobilization of porcine carotid arteries for tissue engineering vascular grafts

Tissue engineering vascular grafts(TEVGs) have the potential to replace small-diameter grafts in bypass surgery which is good news for patients with cardiovascular disease. Decellularizedarteries can be ideal TEVGs because their natural three-dimensional structures support the migration of host cells and vascular remodeling. There are many methods for decellularizationwithout a standard protocol. In this study, a combination of Triton X-100and sodium dodecyl sulfate (SDS) were used to prepare decellularizedarteries. However, decellularizationmay damage the biochemical and mechanical properties to some degree. We used the cross-linking agents N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide(NHS) to improve mechanical properties and immobilize heparin to inhibit thrombogenesis. Histological analysis, scanning electron microscopy, biomechanical properties test, determination of immobilized heparin, active partial thrombin timeassay, and subcutaneous embedding experiment were used to evaluate the efficiency of decellularizationand the efficacy of heparinized cross-linked vascular scaffold. Results showed 1% Triton X-100combined with 0.3% SDS can decellularizesuccessfully. EDC and NHS cross-linking can improve the mechanical properties, reduce the inflammatory reaction and slow the degradation time. Heparin immobilized on the scaffolds can inhibit thrombogenesis effectively. This study indicated the heparinized cross-linked vascular scaffolds may be ideal scaffolds for TEVGs.