Preparation and evaluation of decellularized porcine carotid arteries cross-linked by genipin: the preliminary results

Decellularized arterieshave been considered as promising scaffolds for small-diameter vascular substitutes. However, weakened mechanical properties, immunological rejection and rapid degradation after transplantation still exist after decellularization. Previous studies indicated that genipin cross-linkingcan solve these problems. Therefore, genipinwas selected as the cross-linkingagent for the pre-treatment of decellularized arteriesin our study. Histological analysis, scanning electron microscopy, mechanical properties analysis and subcutaneous embedding experiment were adopted to investigate the efficiency of decellularizationand the effect of genipin cross-linkingon improving mechanical, structural and biological properties of decellularized arteries. Decellularizationprotocols based on three trypsin concentrations were used to prepare decellularized arteries, after decellularization, arterieswere cross-linkedwith genipin. Results showed that 0.5% trypsin was the most efficient concentration to remove cellular componentsand preserve ECM. However, mechanical properties of 0.5% trypsin decellularized arteriesweakened significantly, while genipin cross-linkingimproved mechanical properties of decellularized arteriesto the same level as fresh arteries. After 4 weeks subcutaneous embedding, cross-linked arteriescaused the mildest inflammatory response. In conclusion, genipincould be employed as an ideal cross-linkingagent to strengthen mechanical properties, enhance the resistance to degradation and reduce the antigenicity of decellularized arteriesfor small-diameter blood vessel tissue engineering applications.