Biointegrated Synthetic Grafts for Reconstruction of Vascular Tissue

Use ofexisting smaller prosthetic grafts for vascular repair and reconstruction after severetrauma to the extremities is greatly limited by issues with stenosis and infection.We propose treating the exterior of ePTFE vascular grafts with STAR biomaterial, a well-developed microporous synthetic tissue scaffold already in human use.STAR prevents the usual formation of a constrictive fibrotic perigraft tissue capsule.Mechanical constriction effects areeliminated, permitting greater freedom for natural pulsatile and vibratory motion of the graft wall.This suppresses progression of neointimal hyperplasia by alleviating compliance mismatch and providing more favorable stress conditions at the ePTFE-neointima interface.The STAR biointerface also addresses the infection risk of ePTFE grafts; STAR biomaterial harnesses the bodys natural antimicrobial defenses by concentrating immune cells to resist infections.These biological responses are regulated by the tightly controlled and optimized porous geometry and do not require use of added biologics.Promising preliminary results suggest that this approach can lead to a major improvementin clinical performance and reliability.Phase II technical objectives aredemonstrating advantages of superior patency and infection control in an ovine arterial bypass model with controlled bacterial challenge, and performing neededbench testingtowards qualifyingthe novel graft design for human use.