Investigation of small diameter decellularised artery as a potential scaffold for vascular tissue engineering

The successful replacement of small-diameter blood vessels, affected by cardiovascular disease, with natural and synthetic bypass grafts remains limited due to long-term patency issues. The development of a small-diameter tissue engineered blood vessel (TEBV), with equivalent biomechanical properties to the vessel being replaced, may provide a potential solution. This thesis aims to determine the biomechanical properties of porcine coronary arteries (PCA) and the corresponding natural matrix scaffold of the artery through short-term decellularisation providing vital information for the development of an optimum TEBV, while also establishing the potential of this natural matrix scaffold to be used as a vascular tissue engineering scaffold. The natural matrix scaffold of small-diameter (< 4 mm) PCA was achieved through a short-term decellularisation method to limit the natural degradation of the tissue. The biomechanical properties of PCA and the corresponding natural matrix scaffold of the artery were established. Tubular segments of PCA, up to 60 mm in length, were perfused with 0.1 м sodium hydroxide for 6 to 12 hours to achieve the natural matrix scaffold. Uniaxial tensile and inflation tests confirmed the scaffold maintains its non-linear response, however a less stiff, more distensible low-load response and stiffer high-load response was found compared to non-decellularised sections. Vascular smooth muscle cells were successfully seeded to the luminal and abluminal surfaces and lateral edges of decellularised sections and attachment and infiltration of the xenogeneic cells after 15 days confirmed the viability of the scaffold as a suitableenvironment for cell growth and infiltration. The maintenance of the internal elastic lamina provided a suitable surface for the attachment of endothelial cells. Biomechanical tests of the cell-infiltrated scaffold confirmed a recovery of the native artery distensibility. Additionally, the bare scaffold remained viable for 30 days under pulsatile flow at physiological pressures confirming its potential as a TEBV scaffold