Core-shell PVA/gelatin electrospun nanofibers promote human umbilical vein endothelial cell and smooth muscle cell proliferation and migration

Cardiovascular disease is the leading cause of death in the world. In this study, coaxial electrospinning is employed to fabricate fibers in a core-shell structure with polyvinyl alcohol (PVA) in the core and gelatin in the shell for evaluation as a potential vascular tissue engineering construct. PVA, a synthetic polymer, provides mechanical strength to the biocompatible and weak gelatin sheath. The HUVEC (human umbilical vein endothelial cells) and rSMC (rat smooth muscle cells) demonstrated a flattened morphology with multiple attachment sites on the gelatin and coaxial scaffolds, with an increase in cell spreading seen as mechanical stiffness of the scaffold increased. Additionally, HUVEC had an increase in migration on the coaxial scaffolds, which was attributed to the increase in stiffness; however, this increase in migration was not seen with the rSMC, which had the highest outward migration on the flat surfaces (tissue culture polystyrene and gelatin film). Overall, these scaffolds are appealing substrates for vascular tissue engineering applications. Statement of Significance The worldwide burden of cardiovascular disease presents an ongoing need and opportunity for creating a variety of vascular prostheses. Fabrication of novel scaffolds and constructs for these are needed, providing strength and biological properties facilitating endothelial (EC) and smooth muscle (SMC) cell attachment, migration, and integration. Using electrospinning we formed 3D core:shell nanofibers and examined their effectiveness as substrates for EC and SMC attachment and growth, compared to a 2D (flat) substrate. We found that ECs attached and grew best on 3D core:shell fibers, whereas SMCs favored 2D gelatin surfaces. Interestingly, we found that EC attachment, migration and growth correlated and improved with increasing fiber stiffness. These materials and insights may foster novel vascular prostheses development.