TOPIC: Poly(ε-caprolactone)/keratin/heparin/VEGF biocomposite mats for vascular tissue engineering

Abstract

Vascular endothelial growth factor (VEGF) is an effective growth and angiogenic

cytokine, which stimulates proliferation and survival of endothelial cells, and promotes

angiogenesis and vascular permeability. Binding VEGF with heparin could protect it

from rapid degradation, subsequently allowing it to be controlled release. Primarily,

poly(ε-caprolactone) (PCL) and keratin were coelectrospun, followed by conjugating

with heparin and subsequently binding VEGF. The loaded heparin and VEGF on these

mats were quantified, respectively. The surface characteristics of mats were investi-

gated by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy

(XPS). The VEGF delivery results indicated these mats could sustainably release VEGF

for 2 weeks. Cell viability assays suggested these mats were valid to accelerate human

umbilical vein endothelial cells (HUVECs) proliferation, while inhibit human umbilical

arterial smooth muscle cells (HUASMCs) growth under the combined actions of VEGF

and heparin. The results tested by blood clotting times (APTT, PT, and TT), hemolysis,

and platelet adhesion indicated the mats were blood compatible. To sum up, these bio-

composite mats are ideal scaffolds for vascular tissue engineering.