Abstract 18465: Human Adipose-Derived Stem Cells for a Vascular Graft

Abstract

The objective of this study is to fabricate a small-diameter tissue engineered blood vessel (TEBV) by using human adipose-derived stem cells (ADSC) in combination with the human amniotic membrane as a mechanically-sound biological substrate. Our technology begins by differentiating adipose-derived stem cells into smooth muscle cells (SMC) and seeding them onto a flat sheet of the amniotic membrane. We assessed our hypothesis that several types of SMC can successfully attach and proliferate on this membrane by fluorescently staining cell nuclei with DAPI and characteristic SMC actin filaments with phallotoxins. The cell-seeded sheet was then wrapped around a 3mm O.D. removable mandrel with 6 revolutions. Human fibrinogen and thrombin were applied to glue the layers together and develop a tubular construct with architecture akin to that of a muscular artery’s tunica media layer. The mechanical integrity of this construct can be further improved upon its exposure to appropriate physiological conditions in a perfusion bioreactor. ADSC can also be differentiated into endothelial cells and seeded into the lumen of this construct to prevent platelet adhesion. The TEBV was characterized for its biochemical and mechanical properties. We examined the vasoactive properties of the vessel in response to agonists such as carbachol, norepinephrine and histamine, and compared our results with porcine coronary arteries. Burst pressure and elastic modulus tests were also performed. In conclusion, adipose-derived stem cells are a viable cell line for differentiation into smooth muscle cells and endothelial cells and may be used in tissue engineering of blood vessels. We have developed a small-diameter TEBV with off-the-shelf availability using a completely biological material seeded with patient-own stem cells.