ELECTROSPINNING TUBULAR SCAFFOLDS TO CREATE AN ANASTOMOSIS WITH USE OF THE CAM ASSAY

Adam Orendain , Eniko Enikov, Jose Carrasco

ELECTROSPINNING TUBULAR SCAFFOLDS TO CREATE AN ANASTOMOSIS WITH USE OF THE CAM ASSAY

Central retinal vein occlusion (CRVO) is a vascular disease characterized by thrombosis of the retinal veins that can eventually lead to ischemia. Ischemic CRVO can then cause macular degeneration and neovascular glaucoma causing partial to full blindness. In this study we determined the feasibility of tissue engineered scaffolds for inducing anastomosis as a possible treatment for CRVO. We utilized electrospinning to produce tubular constructs from nano-fibers using type I collagen dissolved in 1,1,1,3,3,3-hexafluoro-2-propanol (HFP). Scaffolds were treated with glutaraldehyde, glycine, ethanol, UV light, and combinations of the treatments for sterilization, cross-linking, and to study their angiogenic effects. Structural properties of the scaffolds were analyzed with scanning electron micrsoscopy (SEM). Scaffolds were immobilized with human recombinant vascular endothelial growth factor (rhVEGF165) to investigate the drug-delivering abilities of the electrospun materials and as a method to produce vascularization, which is a common problem in tissue engineering. We employed the chick chorioallantoic membrane (CAM) assay to examine the effects of VEGF immobilization, chemical treatment of scaffolds, and to evaluate the feasibility of creating an anastomosis. Scaffold onplants and implants were made on day 10 of embryonic development. We found that scaffolds loaded with rhVEGF165 had improved vasculature and pro-angiogenic properties, but failed to create a significant anastomosis between vessels. Onplants treated only with rhVEGF165 had vertical penetration of vessels into the collagen matrices, suggesting they are ideal drug-delivering materials. Our results indicate that electrospun type I collagen nano-fibers can immobilize and control delivery of growth factor. The electrospun scaffolds also presented similar characteristics of the extra-cellular matrix of blood vessels and holds promise for blood vessel engineering.

Sponsored by NIH T34 GM08718

Conference Home | List of Abstracts | Photo Gallery