Mechanical properties of tissue engineered constructs with increased crosslinking of the extracellular matrix

A major issue with tissue engineered vascular grafts has been burst failure due to inadequate mechanical properties of the engineered arterial tissue. Crosslinking and elaboration of extracellular matrix (ECM) proteins are largely responsible for mechanical integrity of vascular tissue. Lysyl Oxidase (LOX) plays a major role in crosslinking elastin and collagen fibers in the ECM. In the current study, the authors are evaluating the effects of increased LOX activity on the mechanical strength of engineered tissues. Two strains of rat aortic smooth muscle cells, one with two-fold higher LOX expression than the control strain, cultured in 3-dimensional collagen type I lattices were used. Significant differences in Young's modulus and ultimate tensile strength were found through dynamic mechanical testing.