Fabric-Reinforced Biomimetic Cell Migration Highway: Micropore Guidance and Vascular Acellular Matrix Regulation for In Situ Vascular Repair.

Abstract

Conventional hydrogel-based vascular grafts often fail because they lack mechanical strength, and their dense structure restricts cell infiltration. To overcome these challenges, we fabricated a bilayer fabric-reinforced composite vascular graft that integrates favorable mechanical properties with biological activity. The inner layer is composed of a hydrogel matrix mixed with vascular acellular matrix (VAM) particles and sacrificial gelatin microspheres, forming an interconnected biomimetic microchannel network that serves as a "cellular highway" to guide and enhance cell migration and tissue regeneration. The outer knitted polylactic acid (PLA) mesh provides substantial mechanical strength and improves suture retention, thereby overcoming the inherent mechanical limitations of hydrogels. After implantation in a rabbit carotid artery model for 3 months, the graft remodeled into a three-layered structure resembling native vessels, demonstrating 100% patency and an effective combination of mechanical strength and biological functionality. This approach addresses key limitations of conventional hydrogel-based vascular grafts and offers a promising strategy for the development of small-diameter vascular grafts. STATEMENT OF SIGNIFICANCE: Conventional hydrogel vascular grafts are plagued by poor mechanical strength and restricted cell infiltration. We engineered a bilayer fabric-reinforced graft: its inner hydrogel-VAM matrix, embedded with sacrificial gelatin microspheres, forms interconnected microchannels as a "cellular highway" for cell migration; the outer knitted PLA mesh enhances mechanical strength and suture retention. Rabbit carotid implantation achieved 100% patency and native vessel-like three-layer remodeling at 3 months. This scalable strategy resolves the mechanical-biological trade-off, advancing vascular tissue engineering and appealing to readers focused on biomaterial clinical translation.