Tissue engineering a blood vessel: Regulation of vascular biology by mechanical stresses

Abstract

Important to the tissue engineering of a substitute blood vessel is an understanding of those factors which regulate vascular biology. A major factor in this regulation is the mechanical environment imposed by the hemodynamics of the vascular system. In this the vascular endothelium plays a critical role, and over the past two decades much has been learned about the influence of hemodynamics on vascular endothelial biology, to a large degree using cell culture to study the effects of flow and cyclic stretch. In our laboratory, such studies are now being extended through the development of a model of the arterial wall involving the co-culture of endothelial cells and smooth muscle cells. The development of such a model and its use in the study of hemodynamic effects represents necessary steps in the evolution of approaches to tissue engineering a blood vessel.

Modeling collagen remodeling

“…Flow of the surrounding fluids induces shear stresses which are sensed by the endothelial cells that line the surfaces of the tissues. These shear stresses are known to be important factors in cardiovascular remodeling (e.g., Nerem, 1993;Ziegler and Nerem, 1994;Humphrey, 2002) and the effects could be incorporated into the models (e.g., Taber, 1998). Also interstitial flow affects extracellular matrix synthesis (Swartz and Fleury, 2007).…”

Biologic alternatives to stents and grafts

“…However, such an animal-derived graft remains untested in human subjects. Related approaches using collagen gels impregnated with cells have been reported by Ziegler et al [34]. However, to date no graft with the mechanical strength of a native vessel has been made using this methodology.…”

Engineering porcine arteries: Effects of scaffold modification

“…This has led to efforts to develop alternative small-caliber vascular grafts. [7][8][9][10][11][12][13][14] The ideal vascular graft should have differentiated, quiescent smooth muscle cells (SMCs), a confluent and quiescent endothelium, and enough mechanical integrity to tolerate physiologic arterial pressures over the long term. 7 A vascular prosthesis must provide compatibility with host tissue and resist rejection, and for this reason, an autologous graft is clearly advantageous.…”