Abstract 9487: Implantation of Scaffold-Free Tubular Tissue Using a Bio-3D Printer Augments Vascular Remodeling and Endothelialization

Abstract

Introduction: Small caliber synthetic vascular grafts are not clinically available. We developed a novel method to create scaffold-free tubular tissue from multicellular spheroids (MCS) using a “Bio-3D printer”-based system, which enables the creation of various three-dimensional structures pre-designed using a computer system. With this system, we created a tubular structure (Fig. 1), and studied its biological features. Methods: We made 1.5 mm in diameter scaffold-free tubular tissues from MCS (1.25 x 10[[Unable to Display Character: ⁷]] cells) composed of human umbilical vein endothelial cells (40%), human aortic smooth muscle cells (10%) and normal human dermal fibroblasts (50%) using a Bio-3D printer. The vessels were cultured in a perfusion system. We implanted grafts into the abdominal aortas of F344 nude rats, and assessed the flow by ultrasonography and performed histological examinations on the second (N=5) and fifth (N=5) days after implantation. Results: All grafts were patent. Remodeling of the vessel (enlargement of the lumen area and thinning of the wall) was observed (Fig. 2). A layer of endothelial cells was developed after implantation of the graft (Fig. 3). Conclusions: The scaffold-free vascular grafts made of MCS using a Bio-3D printer showed biological features comparable to native vessels. Further studies are warranted toward the clinical application of this novel technology.