Showcase of Undergraduate Research and Creative Endeavors (SOURCE)

Evaluating the Effects of Detergent Concentration on the Ultrastructure and Recellularization of Porcine Internal Thoracic Artery Scaffolds

Heart disease is the leading cause of death in developed countries, leading to an increase demand for coronary artery bypass graft surgeries. Currently, bypass surgery requires either that a vessel is harvested from the patient or that a donor graft is provided. An alternative approach is the use of tissue-engineered vascular grafts. The goal of this study is to evaluate the potential of scaffolds derived from porcine internal thoracic arteries (PITAs) for use in vascular tissue engineering. PITA scaffolds can be produced through the process of decellularization, which uses detergents to remove porcine (pig) cells while leaving behind the extracellular matrix of the tissue. We hypothesized that increasing detergent concentration during decellularization would affect the ultrastructure of PITA scaffolds and be associated with greater residual cytoxicity. We evaluated the ultrastructure of the scaffolds using scanning electron microscopy and observed that increasing detergent concentration was associated with greater scaffold porosity. We evaluated the residual cytotoxicity of the scaffolds using the alamarBlue viability assay and found that extensive rinsing is required to eliminate scaffold cytotoxicity. We verified the ability of endothelial cells to grow on/in the scaffolds using a combination of the alamarBlue viability assay and fluorescent microscopy. Taken together, our results show that PITA scaffolds with different ultrastructural features can be prepared and repopulated with endothelial cells as long as the scaffolds are properly rinsed. Establishing an effective procedure for recellularization of PITA scaffolds will ultimately aid in the development of a clinically relevant alternative to our current options for vascular grafts.