Micropatterned angiogenesis induced by poly(d,l-lactic-co-glycolic acid) mesh-structured scaffolds

Abstract

Angiogenesis is an important process used to guide the regeneration of functional tissues and organs. The incorporation of inductive cues into scaffolds to control angiogenesis is an attractive strategy for scaffold preparation. Four mesh-type scaffolds, including a vascular endothelial growth factor-embedded poly(d,l-lactic- co-glycolic acid) mesh, a vascular endothelial growth factor-coated poly(d,l-lactic- co-glycolic acid) mesh, a collagen-coated poly(d,l-lactic- co-glycolic acid) mesh, and a poly(d,l-lactic- co-glycolic acid) mesh, were compared for their inductive effects on the formation of a micropatterned capillary network. Following subcutaneous implantation, all of the scaffolds induced the formation of micropatterned capillary networks, as observed at 2 and 6 weeks after implantation. The vascular endothelial growth factor-embedded mesh and the vascular endothelial growth factor-coated mesh promoted a higher degree of blood vessel formation than the collagen-coated mesh and the poly(d,l-lactic- co-glycolic acid) mesh. The capillary density in the vascular endothelial growth factor-embedded mesh and the vascular endothelial growth factor-coated mesh increased with time following implantation. The macrophages that surrounded the scaffolds were similar for all the meshes. The microstructure of the poly(d,l-lactic- co-glycolic acid) mesh determined the micropattern of the capillary network, and vascular endothelial growth factor provided a synergistic effect on the micropatterned angiogenesis process.