VEGF release from a polymeric nanofiber scaffold for improved angiogenesis

Angiogenesis plays a pivotal role in tissue engineering and regenerative medicine. This study aimed to develop an electrospun fiber scaffold that supports release of recombinant human vascular endothelial growth factor (rhVEGF) to enhance angiogenesis. Scaffolds composed of core–shell fibers were fabricated using co-electrospinning. The core solution was composed of polyethylene oxide and mixed with rhVEGF. The shell solution was composed of polycarpolactone, with 0.25, 1, and 3% of polyethylene glycol (PEG) to manipulate pore size on the shell. Pore size and density increased with higher PEG concentrations. Similarly, rhVEGF release was affected by PEG concentration: initial burst release was found in all scaffolds, followed by continuous 4 h release in 3% PEG and 18 h release in the 0.25 and 1% PEG polymeric scaffolds. Endothelial cell migration toward rhVEGF-incorporated polymeric scaffold was 80-fold higher as compared to VEGF-free polymeric scaffold. In a subcutaneous mouse model, VEGF-incorporated polymeric scaffold stimulated cell migration into the scaffold within three days and significantly enhanced blood vessels formation within 14 days, whereas control scaffolds contained few vessels. In conclusion, the described novel scaffold represents a promising device for vascular tissue engineering, which may be of clinical significance in treating vascular deficient wounds.