Angiogenesis of full-thickness burn wounds repaired with collagen-sulfonated carboxymethyl chitosan porous scaffold encoding vascular endothelial growth factor DNA plasmids

To investigate the effects of vascular endothelial growth factor (VEGF) DNA plasmids, encoded in collagen-sulfonated carboxymethyl chitosan porous scaffold, on the angiogenesis in full-thickness burn wounds. Wounds and pathological changes were observed at Week 1, 2, 3 and 4 after pure collagen-sulfonated carboxymethyl chitosan porous scaffold (group A) and collagen-sulfonated carboxymethyl chitosan porous scaffold encoding VEGF DNA plasmids (group B) were transplanted onto eachar-removed wounds of full-thickness burn in 6 Bama miniature pigs respectively. Wound healing was observed by pathologic slides after epidermal grafting for 2 weeks (at Week 4) onto the surface of different dermal scaffolds transplanted on wounds for 2 weeks. At the same time, new-forming vessels expressing CD31 and mature vessels expressing α-SMA (α-smooth muscle actin) and the expression of VEGF in wounds at Week 1, 2, 3 and 4 were detected in situ by immunohistochemical staining. The burn wounds without any transplanted scaffold (gr